Hydro-culture: A New Farming Technique
The word hydroponics has its derivation from the combining of two Greek words, hydro meaning water and ponosmeaning labor, i.e., working water. The word first appeared in a scientific magazine article (Science, Feb 178:1) published in 1937 and authored by W.F. Gericke, who had accepted this word as was suggested by Dr. W.A. Setchell at the University of California. Dr. Gericke began experimenting with hydroponic growing techniques in the late 1920s and then published one of the early books on soilless growing (Gericke, 1940). Later he suggested that the ability to produce crops hydroponically would no longer be “chained to the soil but certain commercial crops could be grown in larger quantities without soil in basins containing solutions of plant food.” What Dr. Gericke failed to foresee was that hydroponics would in the future be essentially confined to its application in enclosed environments for growing high cash value crops and would not find its way into the production of a wide range of commercial crops in open environments.
The author went to three dictionaries and three encyclopedias to find how hydroponics is defined. Webster’s New World College Dictionary,Fourth Edition, 1999, defines hydroponics as “the science of growing or the production of plants in nutrient-rich solutions or moist inert material, instead of soil”; the Random House Webster’s College Dictionary,1999, as “the cultivation of plants by placing the roots in liquid nutrient solutions rather than in soils; soilless growth of plants”; and The Oxford English Dictionary,2nd Edition, 1989, as “the process of growing plants without soil, in beds of sand, gravel, or similar supporting material flooded with nutrient solutions.” In the Encyclopedia Americana,International Edition, 2000, hydroponics is defined as “the practice of growing plants in liquid nutrient cultures rather than in soil,” in The New Encyclopaedia Britannica, 1997 as “the cultivation of plants in nutrient-enriched water with or without the mechanical support of an inert medium, such as sand or gravel,” and in The World Book Encyclopedia,1996 as “the science of growing plants without soil.”The most common aspect of all these definitions is that hydroponics means growing plants without soil, with the sources of nutrients either a nutrient solution or nutrient-enriched water, and that an inert mechanical root support (sand or gravel) may or may not be used. It is interesting to note that in only two of the six definitions is hydroponics defined as a “science.” Searching for definitions of hydroponics in various books and articles, the following were found. Devries (2003) defines hydroponic plant culture as “one in which all nutrients are supplied to the plant through the irrigation water, with the growing substrate being soilless (mostly inorganic), and that the plant is grown to produce flowers or fruits that are harvested for sale.”
In addition, Devries (2003) states, “hydroponics used to be considered a system where there was no growing media at all, such as the nutrient film technique in vegetables. But today it’s accepted that a soilless growing medium is often used to support the plant root system physically and provide for a favorable buffer of solution around the root system.”
Resh (1995) defines hydroponics as “the science of growing plants without the use of soil, but by use of an inert medium, such as gravel, sand, peat, vermiculite, pumice, or sawdust, to which is added a nutrient solution containing all the essential elements needed by the plant for its normal growth and development.” Wignarjah (1995) defines hydroponics as “the technique of growing plants without soil, in a liquid culture.” In an American Vegetable Grower article entitled “Is hydroponics the answer?” (Anonymous, 1978), hydroponics was defined for the purpose of the article as “any method which uses a nutrient solution on vegetable plants, growing with or without artificial soil mediums.” Harris (1977) suggested that a modern definition of hydroponics would be “the science of growing plants in a medium, other than soil, using mixtures of the essential plant nutrient elements dissolved in water.” Jensen (1997) stated that hydroponics “is a technology for growing plants in nutrient solutions (water containing fertilizers) with or without the use of an artificial medium (sand, gravel, vermiculite, rockwool, perlite, peat moss, coir, or sawdust) to provide mechanical support.” Jensen (1997) defined the growingof plants without media as “liquid hydroponics” and with media as “aggregate hydroponics.” Another defining aspect of hydroponics is how the nutrient solution system functions, whether as an “open” system in which the nutrient solution is discarded after passing through the root mass or medium, or as a “closed” system in which the nutrient solution, after passing through the root mass or medium, is recovered for reuse. Similarly related hydroponic terms are “aqua (water) culture,” “hydroculture,” “nutriculture,” “soilless culture,” “soilless agriculture,” “tank farming,” or “chemical culture.” A hydroponicist is defined as one who practices hydroponics, and hydroponicum defined as a building or garden in which hydroponics is practiced.
Source: Oasis Agro Industries Pakistan
PLANT HORMONES
Hormone:
A hormone is a chemical released by a cell, a gland, or an organ in one part of the body that affects cells in other parts of the organism. Only a small amount of hormone is required to alter cell metabolism.
Plant Hormones:
Plant hormones, also known as phytohormones, are chemicals that regulate plant growth, which, in the UK, are termed 'plant growth substances'.
Plant hormones are signal molecules produced within the plant, and occur in extremely low concentrations. Hormones regulate cellular processes in targeted cells locally and, when moved to other locations, in other locations of the plant.
Hormones also determine the formation of flowers, stems, leaves, the shedding of leaves, and the development and ripening of fruit. Plants, unlike animals, lack glands that produce and secrete hormones. Instead, each cell is capable of producing hormones. Plant hormones shape the plant, affecting seed growth, time of flowering, the sex of flowers, senescence of leaves, and fruits. They affect which tissues grow upward and which grow downward, leaf formation and stem growth, fruit development and ripening, plant longevity, and even plant death.
Classes Of Plant Hormones:
There are five generally recognized classes of plant hormone, some of the classes are represented by only one compound, others by several different compounds. They are all organic compounds, they may resemble molecules which turn up elsewhere in plant structure or function, but they are not directly involved as nutrients or metabolites.
There is only one naturally occurring Auxin: indole-3-acetic acid (IAA) and this is chemically related to the amino acid tryptophan. Auxins were the first plant hormones discovered. The term auxin is derived from the Greek word auxein which means to grow.
Functions of Auxin:
The following are some of the responses that auxin is known to cause (Davies, 1995; Mauseth, 1991; Raven, 1992; Salisbury and Ross, 1992).
The following are some of the responses that auxin is known to cause (Davies, 1995; Mauseth, 1991; Raven, 1992; Salisbury and Ross, 1992).
- Stimulates cell elongation .
- Stimulates cell division in the cambium and, in combination with cytokinins in tissue culture .
- Stimulates differentiation of phloem and xylem .
- Stimulates root initiation on stem cuttings and lateral root development in tissue culture .
- Mediates the tropistic response of bending in response to gravity and light .
- The auxin supply from the apical bud suppresses growth of lateral buds
- Delays leaf senescence .
- Can inhibit or promote (via ethylene stimulation) leaf and fruit abscission.
- Can induce fruit setting and growth in some plants .
- Involved in assimilate movement toward auxin possibly by an effect on phloem transport .
- Stimulates growth of flower parts.
- Stimulates the production of ethylene at high concentrations.
- Auxins also play a key role in tropism (controlling the direction of plant growth).
2. ABSCISIC ACID:
Abscisic acid, also called ABA, was discovered and researched under two different names before its chemical properties were fully known, it was called dormin and abscicin II. Once it was determined that the two compounds are the same, it was named abscisic acid. The name "abscisic acid" was given because it was found in high concentrations in newly abscissed or freshly fallen leaves.
This acid is known for its role in drought environments and inhibiting seed germination. We’ll talk about seed germination later on when we discuss giberellin, so let’s go with dry environments. When the plant senses it is dry it releases abscisic acid, which tells the Stoma to close.
Functions of Abscisic Acid:
The following are some of the physiological responses known to be associated with abscisic acid (Davies, 1995; Mauseth, 1991; Raven, 1992; Salisbury and Ross, 1992).
The following are some of the physiological responses known to be associated with abscisic acid (Davies, 1995; Mauseth, 1991; Raven, 1992; Salisbury and Ross, 1992).
- Stimulates the closure of stomata (water stress brings about an increase in ABA synthesis).
- Inhibits shoot growth but will not have as much affect on roots or may even promote growth of roots.
- Induces seeds to synthesize storage proteins.
- Inhibits the affect of gibberellins on stimulating de novo synthesis of a-amylase.
- Has some effect on induction and maintenance of dormancy.
- Induces gene transcription especially for proteinase inhibitors in response to wounding which may explain an apparent role in pathogen defense.
- Abscisic acid is considered the “stress” hormone. It inhibits the effects of other hormones to reduce growth during times of plant stress.
3. CYTOKININS:
Cytokinins are compounds derived from a nitrogen-containing compound (adenine). Kinetin was the first cytokinin discovered and so named because of the compounds ability to promote cytokinesis (cell division). Though it is a natural compound, It is not made in plants, and is therefore usually considered a "synthetic" cytokinin (meaning that the hormone is synthesized somewhere other than in a plant). The most common form of naturally occurring cytokinin in plants today is called zeatin which was isolated from corn (Zea mays).
These are compounds that increase cell number, promoting cell division. Cytokines are released at the root tips and move up the plant. Cytokine and auxin together causes the plant to form a callus, the cells continue to divide without differentiating. This would be the equivalent as plant cancer, but unlike human cancer callus allow the plant to heal. We use plant calluses when propagating with tissue culture.
Functions Of Cytokinins:
A list of some of the known physiological effects caused by cytokinins are listed below. The response will vary depending on the type of cytokinin and plant species (Davies, 1995; Mauseth, 1991; Raven, 1992; Salisbury and Ross, 1992).
- Stimulates cell division.
- Stimulates morphogenesis (shoot initiation/bud formation) in tissue culture.
- Stimulates leaf expansion resulting from cell enlargement.
- May enhance stomatal opening in some species.
- Promotes the conversion of etioplasts into chloroplasts via stimulation of chlorophyll synthesis.
4. Ethylene:
Ethylene, unlike the rest of the plant hormone compounds is a gaseous hormone. Of all the known plant growth substance, ethylene has the simplest structure. It is produced in all higher plants and is usually associated with fruit ripening.
Ethylene is also a hormone released when the plant is stressed. While abscisic acid’s main job is a plant’s drought response, ethylene is a multi-purpose stress hormone. One example of its use is a growing seedling. If a seedling is growing and hits a rock it will release ethylene, which will cause its stem to grow shorter, thicker, and curvier. With this bending the seedling will grow around the rock.
Functions of Ethylene:
Ethylene is known to affect the following plant processes (Davies, 1995; Mauseth, 1991; Raven, 1992; Salisbury and Ross, 1992):
Ethylene is known to affect the following plant processes (Davies, 1995; Mauseth, 1991; Raven, 1992; Salisbury and Ross, 1992):
- Stimulates the release of dormancy.
- Stimulates shoot and root growth and differentiation (triple response)
- May have a role in adventitious root formation.
- Stimulates leaf and fruit abscission.
- Stimulates Bromiliad flower induction.
- Induction of femaleness in dioecious flowers.
- Stimulates flower opening.
- Stimulates flower and leaf senescence.
- Stimulates fruit ripening.
. Giberellin was discovered in Japan while researching “bakanae” this is Japanese for foolish seedings. The bakanae disease caused rice plants to grow extremely fast, so fast that the plant would not be able to support itself and fall over into the rice patty. Gibberellins are named after the fungus Gibberella fujikuroi, which produces excessive growth and poor yield in rice plants. Gibberellins, abundant in seeds, are also formed in young leaves and in roots; they move upward from the roots in the xylem (woody tissue) and thus do not show the movement characteristic of auxins.
Functions of Gibberellins:
Active gibberellins show many physiological effects, each depending on the type of gibberellin present as well as the species of plant. Some of the physiological processes stimulated by gibberellins are outlined below (Davies, 1995; Mauseth, 1991; Raven, 1992; Salisbury and Ross, 1992).
Active gibberellins show many physiological effects, each depending on the type of gibberellin present as well as the species of plant. Some of the physiological processes stimulated by gibberellins are outlined below (Davies, 1995; Mauseth, 1991; Raven, 1992; Salisbury and Ross, 1992).
- Stimulate stem elongation by stimulating cell division and elongation.
- Stimulates bolting/flowering in response to long days.
- Breaks seed dormancy in some plants which require stratification or light to induce germination.
- Stimulates enzyme production (a-amylase) in germinating cereal grains for mobilization of seed reserves.
- Induces maleness in dioecious flowers (sex expression).
- Can cause parthenocarpic (seedless) fruit development.
- Can delay senescence in leaves and citrus fruits.
http://www.hcs.ohio-state.edu/hcs300/hormone.htm
http://www.emc.maricopa.edu/faculty/farabee/biobk/biobookplanthorm.html
http://www.plant-hormones.info/auxins.htm
http://en.wikipedia.org/wiki/Plant_hormone#Classes_of_plant_hormones
http://www.cmg.colostate.edu/gardennotes/145.html
TEXTBOOK OF BIOCHEMISTRY- Harrow-Mazhur
About Author:
Syeda Tahira Fatima Jafri
Website URL: http://agriculturism.blogspot.com/
BIO: I am doing my B.S. (IInd Year) in Agriculture & Agribusiness Management at the University of Karachi.
E-mail: fatimajafri@live.com
Feeding the community one garden at a time
May 29, 2013, by Leslie Davis
Our mission is to reduce hunger in our community by growing gardens, gleaning fruit from local orchards and soliciting produce donations at our local grower’s market. Produce harvested is often in the hands of the families who need it within hours of harvest. Picked fresh. Distributed fresh. Consumed locally by families facing food insecurity.
Leslie Davis
505.933.1345
www.Seed2Need.us
Facebook: Seed2Need
Seed2Need@gmail.com
I work with a non-profit organization, Seed2Need, outside of Albuquerque, New Mexico that grows gardens to generate fresh produce for local food pantries. New Mexico consistently ranks high for poverty and food insecurity. Funding available to our central food bank has been reduced due to state and federal budget constraints. With so many relying on their services, they cannot afford to invest in perishable commodities, but the importance of fruit and vegetables to basic nutrition cannot be denied. Addressing the issue at a localized level seemed like the most efficient way to alleviate the problem.
Our mission is to reduce hunger in our community by growing gardens, gleaning fruit from local orchards and soliciting produce donations at our local grower’s market. Produce harvested is often in the hands of the families who need it within hours of harvest. Picked fresh. Distributed fresh. Consumed locally by families facing food insecurity.
What started as a small garden in a neighbor’s horse corral to supply one food pantry has evolved over the last five years into Seed2Need; now serving 15 food pantries and soup kitchens in the area. Our community is very supportive, with many local property owners donating land, equipment and excess fruit from their orchards. We receive financial assistance from local businesses and individuals. We have volunteers of all ages and every walk of life. Our organization involves service by the community for the community.
Many of us have an interest in gardening, but no background in agriculture. This has been an educational experience for many, if not most, of the volunteers involved. There has been a steep learning curve as we realize what we are doing wrong and recognize what we are doing right, changing and adapting as we progress. The varieties of produce have been altered based on productivity and various planting, irrigation and mulching techniques have been modified to increase efficiency. As a volunteer organization we have to be aware of cost effective, labor saving methods.
Growing in New Mexico is nothing like growing in the more fertile climates of the Midwest or Southern states. New Mexico is a dry, arid, hot, high mountain climate. We have been experiencing a prolonged, extreme drought over the last several years. As a result of the drought, many farmers are unable to plant crops this summer, making the cost of fresh produce more cost prohibitive to families experiencing economic hardship and making water conservation a vital part of our plan. Although our gardens are close to the Rio Grande River we utilize a T-Tape drip irrigation system, drawn from a well, rather than relying on flood irrigation. This reduces the weeds brought in from flood irrigation and conserves water by applying small increments directly to the plants. We also utilize plastic mulch to prevent rapid evaporation and to create a barrier for weeds.
We have chosen vegetables that produce over a period of time, rather than a singular harvest, to ensure that we can provide a plentiful supply over several months. We also take into consideration regional tastes and diet. Currently we are growing 2 acres of tomatoes, green chile, cucumbers, watermelons, cantaloupe, zucchini and green beans. Over the last three years we have generated 70 tons of produce for local food pantries. With two acres planted this spring we are hoping to harvest 30 tons this summer alone.
For more information please visit our website, www.Seed2Need.us, or like our Seed2Need page on Facebook. If you have any questions about our techniques or starting a garden to address hunger within your community, please email Seed2Need@gmail.com.
Bio: Leslie Davis has a finance and economics degree with 25 years of sales and marketing experience and a desire to apply those skills to make a positive impact on her community.
Contact Info: www.Seed2Need.us Leslie Davis
505.933.1345
www.Seed2Need.us
Facebook: Seed2Need
Seed2Need@gmail.com
Mango nutrition facts: How a mango is nutritious
“The king of the fruits," mango fruit is one of the most popular, nutritionally rich fruits with unique flavor, fragrance, taste, and heath promoting qualities making it a common ingredient in new functional foods often labeled “super fruits."
Mango is one of the delicious seasonal fruits grow in the tropics. The tree is believed to be originating in the sub-Himalayan plains of Indian subcontinent. Botanically, this exotic fruit belongs within the family of Anacardiaceae, a family that also includes numerous species of tropical-fruiting trees in the flowering plants such as cashew, pistachio,...etc.
Mango is a tropical seasonal fruit, which saw its origin in the sub-Himalayan plains of India. There are different types and varieties of mango available in the market today. There are extremely juicy variants of mangoes available. Some mangoes have a small seed while some retain a big one. It is better to opt for those which are more fleshy, sweet and juicy to avail of maximum flavor. Alfonso is one of the breeds of mangoes, which is immensely popular, amongst people of all countries.
Mango is considered to be the king of fruits. It is widely popular in different corners of the world. Its unique flavor manages to turn on, even a non-fruit consumer. It also serves as a perfect beverage if blended with milk and sugar. The prepared beverage is also often termed as a mango smoothie or a mango-shake. It has a unique color and fragrance, which always manages to capture the attention of fruit lovers. Mango stands tall amongst the list of new functional foods known as ‘super fruits’. Along with providing a delicious and delectable taste, numerous health benefits are also offered by the king of fruits. Numerous mango nutrition facts are there, which should be first understood, before digging in to devour the delightful fruit.
Mango is considered to be one of the most nutritious food items. Numerous health benefits are offered by mangoes. Let us vide at some of the important mango nutrition facts which are there. Mangoes are rich in pre-biotic dietary fiber. They are also rich in vitamins and minerals which are essential in strengthening body parts. They are also helpful in maintaining a healthy body. Poly-phenolic flavonoid antioxidant compounds are present in mangoes which help in expelling harmful toxins from the body. Such compounds also help in fighting various diseases. The antioxidant compounds present in mango offer excellent protection against breast and colon cancers.
Other mango nutrition facts boast of a mango’s high vitamin quotient. Mangoes are an excellent source of Vitamin-A. Deficiency of Vitamin-A might cause night blindness. It is very important to increase the intake of mangoes in one’s diet to get rid of eye related problems. Mangoes are also rich in potassium which helps in controlling the heart rate and blood pressure. Another fact that could be placed in the list of mango nutrition facts is that, a mango poses as an excellent source of beta-carotene and alpha-carotene and beta-cryptoxanthin, all of which retain antioxidant properties and are considered essential for vision. Such compounds are also necessary for the maintenance of healthy mucus membranes and skin. Vitamin-C and E are also available, which are necessary for creating resistance against infectious agents and harmful radicals. Mangoes are also ingested in their raw form in many countries. The raw form of a mango offers a unique sour taste, which is turned delicious by the addition of condiments and spices, in various places. Ingesting beverages made of raw mangoes, helps a person to avoid getting hit with sun strokes.
Health benefits of Mangoes
- Mango fruit is rich in pre-biotic dietary fiber, vitamins, minerals, and poly-phenolic flavonoid antioxidant compounds.
- According to new research study, mango fruit has been found to protect against colon, breast, leukemia and prostate cancers. Several trial studies suggest that polyphenolic anti-oxidant compounds in mango are known to offer protection against breast and colon cancers.
- Mango fruit is an excellent source of Vitamin-A and flavonoids like beta-carotene, alpha-carotene, and beta-cryptoxanthin. 100 g of fresh fruit provides 765 mg or 25% of recommended daily levels of vitamin A. Together; these compounds are known to have antioxidant properties and are essential for vision. Vitamin A is also required for maintaining healthy mucus membranes and skin. Consumption of natural fruits rich in carotenes is known to protect the body from lung and oral cavity cancers.
- Fresh mango is a good source of potassium. 100 g fruit provides 156 mg of potassium while just 2 mg of sodium. Potassium is an important component of cell and body fluids that helps controlling heart rate and blood pressure.
- It is also a very good source of vitamin-B6 (pyridoxine), vitamin-C and vitamin-E. Consumption of foods rich in vitamin C helps the body develop resistance against infectious agents and scavenge harmful oxygen-free radicals. Vitamin B-6 or pyridoxine is required for GABA hormone production within the brain. It also controls homocystiene levels within the blood, which may otherwise be harmful to blood vessels resulting in CAD and stroke.
- Further, it composes moderate amounts of copper. Copper is a co-factor for many vital enzymes, including cytochrome c-oxidase and superoxide dismutase (other minerals function as co-factors for this enzyme are manganese and zinc). Copper is also required for the production of red blood cells.
- Additionally, mango peel is also rich in phytonutrients, such as the pigment antioxidants like carotenoids and polyphenols.
Did You Know?
One cup of mangos is just 100 calories, so it’s a sweet treat that won’t weigh you down.
Each serving of mango is fat free, sodium free and cholesterol free.
Mangos contain over 20 different vitamins and minerals.
Biotechnology adoption can help overcome agriculture challenges
Pakistan can address challenges in agriculture by using biotechnology as globally the adoption of genetically modified crops has been a success with proven socio-economic benefits.
In addition to meeting food security challenge, genetically modified/biotech crops offer multiple economic, crop management, productivity, and environmental benefits. Benefits that these crops offer include, but not limited to, better yields and guarding against insect pests and weeds as well as being cost effective and less labour intensive.
These views were expressed by the experts of biotechnology industry while briefing a delegation of the Agricultural Journalists Association (AJA) about latest agricultural technologies including biotechnology during their visit to Monsanto Pakistan's state-of-the-art research centre in Manga Mandi, where the company is conducting field trials of its GM corn product and various vegetables and fruits. The journalists also visited the field trails sites.
On this occasion, Monsanto Pakistan Regulatory Affairs Lead Muhammad Asim, and Breeding Lead Abdul Ghaffar briefed the visitors about the benefits of GM corn as well as biotechnology. They informed the journalists that their company had completed the field trials of GM corn and now they were awaiting government's approval to launch the product in the market. They claimed that GM corn can increase the productivity of corn, an important food crop after wheat and rice, by considerably decreasing the losses caused by insect pests and weeds. They said that farmers were well aware of this problem with no solution. They said Pakistan already had a quantum jump in corn production after introduction of hybrid varieties. They claimed that yield increase in spring season is at 2.5 times higher whereas in autumn is 3.5 times. According to their briefing in 1990 spring yield of corn was around 40 maund per acre which jumped to 100 maund per acre in 2010.
However, they were of the view that more increase in production could only be ensured through introduction GM varieties. They said that corn is sown on one million hectares in Pakistan including 445,000 hectares in Punjab and 550,000 hectares in Khyber Pakhtunkhwa. They said consumption of corn in Pakistan is approximately about 3.8 million tones and its increasing.
In addition to meeting food security challenge, genetically modified/biotech crops offer multiple economic, crop management, productivity, and environmental benefits. Benefits that these crops offer include, but not limited to, better yields and guarding against insect pests and weeds as well as being cost effective and less labour intensive. These views were expressed by the experts of biotechnology industry while briefing a delegation of the Agricultural Journalists Association (AJA) about latest agricultural technologies including biotechnology during their visit to Monsanto Pakistan's state-of-the-art research centre in Manga Mandi, where the company is conducting field trials of its GM corn product and various vegetables and fruits. The journalists also visited the field trails sites.
On this occasion, Monsanto Pakistan Regulatory Affairs Lead Muhammad Asim, and Breeding Lead Abdul Ghaffar briefed the visitors about the benefits of GM corn as well as biotechnology. They informed the journalists that their company had completed the field trials of GM corn and now they were awaiting government's approval to launch the product in the market. They claimed that GM corn can increase the productivity of corn, an important food crop after wheat and rice, by considerably decreasing the losses caused by insect pests and weeds. They said that farmers were well aware of this problem with no solution. They said Pakistan already had a quantum jump in corn production after introduction of hybrid varieties. They claimed that yield increase in spring season is at 2.5 times higher whereas in autumn is 3.5 times. According to their briefing in 1990 spring yield of corn was around 40 maund per acre which jumped to 100 maund per acre in 2010.
However, they were of the view that more increase in production could only be ensured through introduction GM varieties. They said that corn is sown on one million hectares in Pakistan including 445,000 hectares in Punjab and 550,000 hectares in Khyber Pakhtunkhwa. They said consumption of corn in Pakistan is approximately about 3.8 million tones and its increasing.
Source: http://www.brecorder.com
Original Article 
Pakistan: Mango export season begins
By Tanveer Sher
Mango export has started in the country on Saturday with an ambitious target of 175,000 tonnes, which is 52 percent higher than the previous season’s target of 115,000 million tonnes.
Export of mango this season is expected to fetch $60 million.
The Ministry of Commerce granted permission to exporters to start export across the country. The objective of the decision was described by exporters on account of avoiding losses through unplanned and premature export of the fruit as witnessed during previous years.
Some 400 metric tonnes of the most favourite fruit of the summer season was airlifted to a number of European and Gulf countries UAE, Qatar, Saudi Arabia, Kuwait, Bahrian, UK and Germany where demand of Pakistani mango is growing with the period of time.
Export of mango this season is expected to fetch $60 million.
The Ministry of Commerce granted permission to exporters to start export across the country. The objective of the decision was described by exporters on account of avoiding losses through unplanned and premature export of the fruit as witnessed during previous years.
Some 400 metric tonnes of the most favourite fruit of the summer season was airlifted to a number of European and Gulf countries UAE, Qatar, Saudi Arabia, Kuwait, Bahrian, UK and Germany where demand of Pakistani mango is growing with the period of time.
According to All-Pakistan Fruit and Vegetable Importers-Exporters and Merchants Association (PFVA) Chairman Waheed Ahmed, the production of mango is being expected at 1.55 million tonnes, while export target of 175,000 metric million tones mango has been set for this year.
Sindh was the most affected province of the climatic hazards facing 150,000 tonnes drop in production with an estimated decline of 25 percent in 2013. The production of mango in Hyderabad, Tando Allayar, Mityari, Mirpurkhas and others parts of the province was badly affected which has also delayed the season by two weeks.Citing hindrances, which hampered mango exports, he said they include international barriers on trade with Iran, which also declined Pakistan’s exports to that country, as Pakistani banks had stopped trade services with Iran, which previously was importing 30,000 tonnes of mangoes from Pakistan. The country suffered a loss of $10 million for not exporting mangoes to Iran, he said adding that the illegal trade or smuggling via land routes was not benefiting the country in terms of revenue.
Besides, despite of being approved for US market mango exports to the foreign country on commercial basis could not take place due to the condition of treating the mangoes at a radiation plant near Chicago and unavailability of direct air service. Treating and processing the fruit in US, according to him is not only a costlier business but also highly risky for the exporters. Besides, the export of the perishable items via sea routes was also not feasible to the businessmen in horticulture sector due to long transit. The only way out to tap the US market is to provide the radiation facility in Pakistan preferably in Karachi and Multan.
Exports to Australia also could not begin because of quarantine issue. Though Australian quarantine team had visited facilities and orchards in the country to check the quality of the fruit for their market, however no development was made in this regard. The Ministry of Commerce and other concerned authorities should move to approach the authorities in the foreign country to have another highly valued market tapped.
Ahmed said during the current year exporters would focus on exports to Japan, Australia, South Korea, US, Mauritius and Lebanon markets and initiatives would be taken to uplift the quality of Pakistani mangoes to increase exports. Pakistan was presently exporting mango to at least 40 countries of the world including Canada, Germany, UK, France, Italy, Island, Denmark, Holland, Switzerland, Belgium, UAE, Saudi Arabia, Bahrain Kuwait, Singapore, Malaysia, South Korea, Lebanon and others. The varieties those commercially exported from Pakistan are Sindhri, Sunhaira, Fajri, Began Phali, Summar Chaunsa, Black Chaunsa and White Chaunsa.
Owing to the holy month of Ramazan falling in the second week of July, the local and international demand of mango is likely to go up as Muslims across the world are sure to enhance their daily consumption of the most demanding fruit of the summer season.
Responding to a query, he said as pledged by the officials of national flag carrier Pakistan International Airlines (PIA) during a meeting with office bearers of the fruit exporters some one month ago, a pro-active role on its part would be highly beneficial for the export of mango during the current season which may ultimately help realisation of ambitious target of 1.75 million tonnes.
Previous year, PIA had been under criticism for not providing enough space and facilities to mango exporters, but this year it has finally formed a new ‘business strategy’ to lift the fruit with maximum quantity. Providing new equipments and space to its cargo facility, the national flag carrier will be grabbing 25 percent share in the country’s cargo revenue this year. By airlifting maximum cargo for European destinations, the airline would easily be getting substantial revenue from mango exports in 2013, which would enable it to reduce its mounting financial losses.
Source: http://www.dailytimes.com.pk
Biogas potential in Pakistan
For the last five years, Ministry of Petroleum and Natural Resources (MPNR) has been trying to implement a LNG project of a rather small capacity of 400 Billion Cubic Feet per year (BCFD) and desperately tried to conclude an agreement in this respect in the last days of the reigning government of PPP.
The LNG rates almost as much as that of oil (more than 80%) which it purports to replace, although there are some merits in that project. However, this is not the purpose of this article to delve into that. Similarly, Pakistan and Iran have both been trying to implement the IP gas pipeline project for years. Finally, the project was inaugurated on Iran side of the border without finalising the contract details and amidst vocal US opposition to the project and the murmur by opposition parties that it was a political inauguration designed to take undue credit and creating problems (of sanctions and US disgruntlement over the issue) for the next government. In this perspective, one would like to desperately search for other options including local production of gas. Biogas emerges as a good option, although not a complete replacement of the imported pipeline gas. It is intended in this article to explore the Biogas potential in Pakistan, its strength and weaknesses and evaluate various strategies to avail of its benefit. We will also explore in the end a rather interesting proposal; the prospects of using Biogas in CNG applications, something which CNG owners may love to read as the sector appears to be facing extinction in the wake of the gas crisis.
Biogas is certainly not a new idea. The idea of producing Biogas for cooking has been on the cards for more than three decades in this country. In 1980s, attempts were made in the days of General Zia-ul-Haq to popularise Biogas. The initiative failed on account of many reasons detailing which may not be called for in this article. Several Rural development programme components are still there, which are dealing with Biogas for cooking with various degree of success or lack of it. Availability of cheaper and abundant gas and petrol resources has been one of the major reasons for underdevelopment of the alternative routes and products in the energy field. No more; neither the conventional sources are any cheaper any more and nor are these abundantly available. We have one-third of our power generation capacity under-utilised because we cannot afford to buy Fuel oil within the existing tariff framework, the latter being already too high and unaffordable for most consumers in the country.
Pakistan a country of 200 million people and a large agriculture and a livestock sector (being the fourth largest milk producer in the world) produces a lot of Biomass and the associated waste. Animal dung, agri-waste, food and other Bio industry waste, Municipal Solid Waste (MSW) and sewerage could all generate valuable Biogas in addition to solving the perennial waste disposal problems. My estimates indicate that Pakistan has a potential of producing as much Biogas as it currently produces from its Gas Wells in Balochistan and Sindh, a whopping 1.6 TCF per year. Why the potential does remains unutilised?
One may argue that nowhere in the world Biogas is a major source of energy. However, the situation is changing fast. Europeans have decided to generate Biogas to cater to the 20% of their gas requirement from Bio-sources by the year 2020 or so. While Americans are revelling in their Shale gas resource which is projected to last them for more than a century, Europeans produce only 40% of their gas requirements domestically and the rest is imported from Russia and the Middle East. In Europe a thriving and reliable gas market and network is operating based on local supplies and imports. Had their situation being as stark as ours, impetus on Biogas would have been even stronger. In any case, a 20% target is no mean a goal.
Pakistan has a livestock population of over 50 million, which alone produces about 1 million ton per day of biomass (dung), most of which gets wasted producing local nuisance and global environmental problems (global warming due to methane release).This alone can generate 4 billion Cft per day, which is the shortfall that we are facing. Easier said than done? Obviously, all of the potential cannot be converted in gas and put into pipe lines. However, oil and gas demand can be reduced by generating and utilising biogas in many direct and indirect ways.
Presently, small biogas plants are being installed for family needs in rural areas. The effort is continuing for the past many years. We have some 20 million rural house-holds. For 50% coverage, we require 5 million small biogas plants. This means, an installation activity of 500,000 biogas plants per year, if 50% target is to be achieved in 10 years. Due to poverty and capital needs, only a partial objective may be achieved in near future. Government subsidy and loan scheme can make a significant difference. The biggest merit of Biogas plants, especially the smaller ones, is that a lot of employment can be generated for the rural unemployed and landless workers. A reasonably sized Biogas programme say 100,000 plants per year can generate a direct employment of 50,000 workers not withstanding the stimulation of demand in cement and bricks sector. Finally, the motivation to shift from burning of Uplas and shrubs is lacking among the cash-starved rural poor.
However, there is scope for commercial and industrial activity and investments in biogas sector. There are about one million agricultural Tube wells in Pakistan, 80% of which run on diesel. At Rs 100 a liter of diesel, the generators cost Rs 25 per unit of electricity generated. Farmers spend about 600-1000 Million USD worth of diesel annually to buy the required diesel to operate these tube wells. Farmers have started investing in Biogas plants that cost them Rs 0.5 million to run their generators. An equivalent solar tube well costs two to three times more. It is expected that wealthier ones would go for solar and less wealth would be installing Biogas plants.
There are 30,000 large farms in Pakistan employing more than 50 cattle and 18000 farms rearing 200 cattle per farm on the average. Large Farms and cattle owners can produce electricity for others and sell it to the grid. A farm having 1000 cattle can generate 0.5 MW of electricity and a farm of 2000 cattle can generate 1 MW. One can reasonably assume that 1000 such farms can be marshaled to provide atleast 1000 MW, against a total potential of 3800 MW. Activity on this scale would require foreign technology and capital. Europeans would be keen to participate in this market, particularly Germany and Sweden where these technologies are thriving. A government policy would have to be evolved to facilitate all this. However, one is always scared of government policies which render every project expensive and unaffordable, the issue of costly Wind Power being a case in point. Wherever feasible, Biogas after cleaning and removing CO2 can also be fed into the gas network. Several such projects are being considered elsewhere and some are in operation as well. Recently, a Pakistani scientist settled in the US had prepared a proposal in this respect. I am not aware as to what happened.
Concluding, in addition to centralized generation and networks, we should also look into distributed energy options. Most alternative energy technologies are suited for distributed mode except wind Power. Energy security and autonomy is enhanced by distributed applications. Centralized systems are too vulnerable to attack, terrorism and other threats and discontinuity. Biogas has a potential to meet our energy demands in a significant way while augmenting Energy security and self-reliance.
PART-II : BIO-CNG-CNG FROM BIOGAS Bio-CNG is CNG produced from Bio sources instead of Natural Gas obtained from oil and gas fields. One could retrofit his CNG station with a Biogas plant and produce his own gas (Methane) instead of buying it from gas distribution companies such as SSGC and SNGPL. Raw material for the adjunct Biogas plant is to come from a variety of bio resources such as solid and liquid wastes and agricultural residues. In this article, we will explore the possibilities and role Bio-CNG can play in meeting the CNG demand in Pakistan.
Factories are closed down due to non-availability of natural Gas. And there are long lines at CNG stations. CNG dealers criticise and even curse the Minister of Oil and Gas for their problems, but the fact is that there is an acute shortage of Gas. CNG dealers would also want to maintain a price differential of 50% between oil and gas prices in order to be able to maximise their revenues and profits. Even if LNG and Iran Gas Pipeline projects are implemented (a big if), gas prices are not going to be the same as these have been and still are. Both Iran and LNG suppliers are asking for very high rates, which is more than double our current rates.
The morale of the story is to look for the other options and alternatives and develop these and stop living in the dream-world of cheap gas. This is a special message for the CNG dealers and their very vocal association. One would like to encourage them to Bio-CNG. As mentioned earlier, Biogas is nothing new, but Bio-CNG is and has come on the agenda only recently due to developments in technology and market. Biogas has 50% Methane and thus has to be upgraded, for use in automotives, to above 90% for technical and economic reasons. Also some gas cleaning is required to remove sulfur. This has been achieved successfully, technically and commercially only recently. One can now produce CNG at 50% of the price of Gasoline in the US Several commercial projects for self use by the producers have been launched.
To reassure the skeptics, let me also reproduce the cuttings from a news-letter (Bio-Master) on the subject, which shows how active and popular the subject is in many countries:
BIOGAS FROM SEWAGE TREATMENT PLANT TO POWER DELHI BUSES
August 2012 Ambitious as it may sound, but Delhi plans to run its buses on biogas. In collaboration with the Swedish government, the Union Ministry of New and Renewable Energy plans to set up a biogas plant inside Kesopur Sewage Treatment Plant (STP) complex in West Delhi.
INDIA TO TEST THE BIO-CNG PRODUCED FROM BAGASSE IN A COMMERCIAL VEHICLE
February 2013 Under instructions from the Union Ministry for New and Renewable Energy (MNRE), Pune-based Automotive Research Association of India is expected to test the bio-CNG produced from bagasse and its use in operating a commercial vehicle. ENOC SIGNS AGREEMENT WITH DUBAI MUNICIPALITY TO PRODUCE CNG FROM WASTE FOR automotive use
February 2013 Emirates Gas LLC (EMGAS), a subsidiary of Emirates National Oil Company (ENOC), has signed a Memorandum of Understanding with Dubai Municipality to treat land and sewage waste to generate compressed natural gas (CNG). EMGAS is now setting up an advanced facility to convert waste to bio-methane, from what is currently being flared, and then compress it into compressed natural gas that will be used as an automotive green.
FIRST ECO-BUS ENTERS SERVICE IN ZALAEGERSZEG (HUNGARY)
August 2012 The first eco-bus of the local public transport company entered service on 27 June. It is fuelled by biomethane, which is derived from the local sewage treatment plant. This action is part of a series of measures which aim to turn Zalaegerszeg into a sustainable town.
TURKU AIMS TO USE MORE BIOGAS BUSES (FINLAND)
October 2012 The city of Turku pledges to use the growing share of biogas to power its city buses. The aim is to make the bus transport within the city as environmentally friendly as possible.
FIRST ECO-BUS ENTERS SERVICE IN ZALAEGERSZEG (HUNGARY) The first eco-bus of the local public transport company entered service on 27 June. It is fuelled by biomethane, which is derived from the local sewage treatment plant. This action is part of a series of measures which aim to turn Zalaegerszeg into a sustainable town.
Ministry of Fuel (MFNRE) in India has approved about 15 projects subsidising up to 50% of the equipment cost of Bio-CNG installations. Local Government of New Delhi has decided to switch to Bio-CNG by producing Biogas from its solid waste facilities and get almost free fuel. Nothing is free though, the amortization costs and operating expenses would still yield a fuel cost saving of 50%. All public transport facilities and projects almost anywhere suffer from high cost issues not sufficiently covered under an affordable tariff. It is said that the newly established Metro-Bus project in Lahore also suffers from the same issue. However, Lahore generates a lot of solid and liquid waste and there should be ample agro-biomass around Lahore to be able to generate enough Bio-CNG at 50% of the Diesel prices. I hope the CM Punjab somehow reads it or get to know about it. Similarly, Karachi or for that matter all major cities can afford a public transport system under a cheaper and locally available fuel, in a country which calls itself an agricultural country. Reportedly, more than 35 CNG Buses procured by the local government of Karachi are in the docks, although for other than cost reasons. But improved economics and lesser fuel costs certainly help.
Although, urban area CNG stations may not be able to benefit from Bio-CNG(except where local government develop projects from organic waste), CNG stations on the highways passing through rural areas can certainly install Bio-CNG facilities. A Bio-CNG plant consumes a lot of space for biogas generation plant, although the same compression facilities as are already available in conventional CNG would be required for compressing and filling Bio-CNG. In Punjab and Sindh, there should be a large number of existing CNG stations that could benefit from this concept. Capital investments of about Rs 10 Million have been estimated for installing Biogas facilities at the existing CNG pumps in rural areas.
A wide variety of Biomass is available; Household and Municipal Solid waste , sewerage and waste water, agricultural, forestry and plant residue. To my knowledge, there is no single location or facility in Pakistan, where solid waste is hygienically and scientifically disposed off, except for some recycling activity self-sustained by commercial recyclers. In most countries particularly in Europe, hitherto, MSW had been incinerated, but now trend is changing towards gasification of solid waste. Waste heat was fed into heat exchangers to supply to the district heating systems or heat utilised in other applications. Incineration has become out of fashion due to environmental reasons as well. Increasingly solid waste is being disposed in Landfills which invariably produce Biogas.
In Pakistan, a number of studies and efforts have been undertaken in the past to generate electricity from Municipal Solid Waste (MSW), but could not succeed due to a variety of reasons including poor economics and comparatively lower Calorific value of Pakistani MSW. Most, in fact all cities throw their MSW in uncovered waste dumps spreading squalor and disease in adjoining areas. Often, it is shamefully and carelessly burnt in the open very close to the residential areas. Any body who has crossed the Korangi bypass at night would know how dangerous this activity is. Bio-gasification and Bio-CNG may improve the economics of collection and disposal of MSW in most communities, especially major cities.
Villages and Rural Centers can replace diesel from their diesel engines of the tube wells. Also, tractors could be switched to Bio-CNG. Where Biomass should be used for producing electricity or where it should be used for Biogas for cooking or for Bio-CNG, would depend on time and space issues and choices of the stakeholders. No policy can be announced promoting or proscribing a certain use, although it is clear that in case of Bio-CNG, the alternative or opportunity cost is much higher, ie Bio-CNG is replacing expensive gasoline and diesel, while there are cheaper options to produce electricity than from Biomass.
Enterprise and innovation is augmented by the economics. A textile entrepreneur in Punjab is reportedly buying several hundred Buffaloes (which in addition to Milk) to provide Gober fuel which would generate Biogas which in turn would be used in electricity generation for his adjacent Textile Mill. The Gober generated Biogas would also be burnt in their Boilers.
Certainly, Bio-CNG would not be a panacea for our energy problems or a one-size-fit-all solution. Cheaper Oil and gas used to be such a panacea and a solution, but no more. But one could expect that a significant portion of CNG demand could be met through Bio-CNG. Localised and segmentised solutions for a variety of users and market conditions may have to be implemented by the private sector mostly, although Government can guide, facilitate and afford some demonstration and early project subsidies. These kinds of solutions such as Bio-CNG, apart from being economic and affordable, also add to our energy security. Imagine what would happen, if oil import facilities or market suffer some kind of blockade or discontinuity, or the law and order problem, affecting the inter-city transport. Biogas is locally produced as would be Bio-CNG.
Concluding, Bio-CNG appears to be an interesting and viable alternative to conventional CNG. Bio CNG should be allowed to grow in an unhindered market environment. Except for quality and safety issues, there should be no regulation, of price or otherwise. It should be the individual CNG dealer's choice weather and where he should invest to produce and sell CNG. However, a government policy would be required to reassure potential investors and the existing CNG dealers that their investment and efforts would not be wasted and that at some point in time, government may start discouraging out. No policy is for ever. Circumstances keep changing and new challenges and issues are to be handled. However, sufficient time and opportunity should be made available before a change of policy stance to enable the investors to recoup their investments. Fortunately, in the case of Bio-CNG, Bio-gasification facility would always have many other alternative markets and usages.
Bio-CNG should be allowed to grow in an uncontrolled market environment. Except for quality and safety issues, there should be no regulation, of price or otherwise. It should be the individual CNG dealer's choice weather and where he should invest to produce and sell CNG.
Table: Biogas Potential in Pakistan The LNG rates almost as much as that of oil (more than 80%) which it purports to replace, although there are some merits in that project. However, this is not the purpose of this article to delve into that. Similarly, Pakistan and Iran have both been trying to implement the IP gas pipeline project for years. Finally, the project was inaugurated on Iran side of the border without finalising the contract details and amidst vocal US opposition to the project and the murmur by opposition parties that it was a political inauguration designed to take undue credit and creating problems (of sanctions and US disgruntlement over the issue) for the next government. In this perspective, one would like to desperately search for other options including local production of gas. Biogas emerges as a good option, although not a complete replacement of the imported pipeline gas. It is intended in this article to explore the Biogas potential in Pakistan, its strength and weaknesses and evaluate various strategies to avail of its benefit. We will also explore in the end a rather interesting proposal; the prospects of using Biogas in CNG applications, something which CNG owners may love to read as the sector appears to be facing extinction in the wake of the gas crisis.
Biogas is certainly not a new idea. The idea of producing Biogas for cooking has been on the cards for more than three decades in this country. In 1980s, attempts were made in the days of General Zia-ul-Haq to popularise Biogas. The initiative failed on account of many reasons detailing which may not be called for in this article. Several Rural development programme components are still there, which are dealing with Biogas for cooking with various degree of success or lack of it. Availability of cheaper and abundant gas and petrol resources has been one of the major reasons for underdevelopment of the alternative routes and products in the energy field. No more; neither the conventional sources are any cheaper any more and nor are these abundantly available. We have one-third of our power generation capacity under-utilised because we cannot afford to buy Fuel oil within the existing tariff framework, the latter being already too high and unaffordable for most consumers in the country. Pakistan a country of 200 million people and a large agriculture and a livestock sector (being the fourth largest milk producer in the world) produces a lot of Biomass and the associated waste. Animal dung, agri-waste, food and other Bio industry waste, Municipal Solid Waste (MSW) and sewerage could all generate valuable Biogas in addition to solving the perennial waste disposal problems. My estimates indicate that Pakistan has a potential of producing as much Biogas as it currently produces from its Gas Wells in Balochistan and Sindh, a whopping 1.6 TCF per year. Why the potential does remains unutilised?
One may argue that nowhere in the world Biogas is a major source of energy. However, the situation is changing fast. Europeans have decided to generate Biogas to cater to the 20% of their gas requirement from Bio-sources by the year 2020 or so. While Americans are revelling in their Shale gas resource which is projected to last them for more than a century, Europeans produce only 40% of their gas requirements domestically and the rest is imported from Russia and the Middle East. In Europe a thriving and reliable gas market and network is operating based on local supplies and imports. Had their situation being as stark as ours, impetus on Biogas would have been even stronger. In any case, a 20% target is no mean a goal.
Pakistan has a livestock population of over 50 million, which alone produces about 1 million ton per day of biomass (dung), most of which gets wasted producing local nuisance and global environmental problems (global warming due to methane release).This alone can generate 4 billion Cft per day, which is the shortfall that we are facing. Easier said than done? Obviously, all of the potential cannot be converted in gas and put into pipe lines. However, oil and gas demand can be reduced by generating and utilising biogas in many direct and indirect ways.
Presently, small biogas plants are being installed for family needs in rural areas. The effort is continuing for the past many years. We have some 20 million rural house-holds. For 50% coverage, we require 5 million small biogas plants. This means, an installation activity of 500,000 biogas plants per year, if 50% target is to be achieved in 10 years. Due to poverty and capital needs, only a partial objective may be achieved in near future. Government subsidy and loan scheme can make a significant difference. The biggest merit of Biogas plants, especially the smaller ones, is that a lot of employment can be generated for the rural unemployed and landless workers. A reasonably sized Biogas programme say 100,000 plants per year can generate a direct employment of 50,000 workers not withstanding the stimulation of demand in cement and bricks sector. Finally, the motivation to shift from burning of Uplas and shrubs is lacking among the cash-starved rural poor.
However, there is scope for commercial and industrial activity and investments in biogas sector. There are about one million agricultural Tube wells in Pakistan, 80% of which run on diesel. At Rs 100 a liter of diesel, the generators cost Rs 25 per unit of electricity generated. Farmers spend about 600-1000 Million USD worth of diesel annually to buy the required diesel to operate these tube wells. Farmers have started investing in Biogas plants that cost them Rs 0.5 million to run their generators. An equivalent solar tube well costs two to three times more. It is expected that wealthier ones would go for solar and less wealth would be installing Biogas plants.
There are 30,000 large farms in Pakistan employing more than 50 cattle and 18000 farms rearing 200 cattle per farm on the average. Large Farms and cattle owners can produce electricity for others and sell it to the grid. A farm having 1000 cattle can generate 0.5 MW of electricity and a farm of 2000 cattle can generate 1 MW. One can reasonably assume that 1000 such farms can be marshaled to provide atleast 1000 MW, against a total potential of 3800 MW. Activity on this scale would require foreign technology and capital. Europeans would be keen to participate in this market, particularly Germany and Sweden where these technologies are thriving. A government policy would have to be evolved to facilitate all this. However, one is always scared of government policies which render every project expensive and unaffordable, the issue of costly Wind Power being a case in point. Wherever feasible, Biogas after cleaning and removing CO2 can also be fed into the gas network. Several such projects are being considered elsewhere and some are in operation as well. Recently, a Pakistani scientist settled in the US had prepared a proposal in this respect. I am not aware as to what happened.
Concluding, in addition to centralized generation and networks, we should also look into distributed energy options. Most alternative energy technologies are suited for distributed mode except wind Power. Energy security and autonomy is enhanced by distributed applications. Centralized systems are too vulnerable to attack, terrorism and other threats and discontinuity. Biogas has a potential to meet our energy demands in a significant way while augmenting Energy security and self-reliance.
PART-II : BIO-CNG-CNG FROM BIOGAS Bio-CNG is CNG produced from Bio sources instead of Natural Gas obtained from oil and gas fields. One could retrofit his CNG station with a Biogas plant and produce his own gas (Methane) instead of buying it from gas distribution companies such as SSGC and SNGPL. Raw material for the adjunct Biogas plant is to come from a variety of bio resources such as solid and liquid wastes and agricultural residues. In this article, we will explore the possibilities and role Bio-CNG can play in meeting the CNG demand in Pakistan.
Factories are closed down due to non-availability of natural Gas. And there are long lines at CNG stations. CNG dealers criticise and even curse the Minister of Oil and Gas for their problems, but the fact is that there is an acute shortage of Gas. CNG dealers would also want to maintain a price differential of 50% between oil and gas prices in order to be able to maximise their revenues and profits. Even if LNG and Iran Gas Pipeline projects are implemented (a big if), gas prices are not going to be the same as these have been and still are. Both Iran and LNG suppliers are asking for very high rates, which is more than double our current rates.
The morale of the story is to look for the other options and alternatives and develop these and stop living in the dream-world of cheap gas. This is a special message for the CNG dealers and their very vocal association. One would like to encourage them to Bio-CNG. As mentioned earlier, Biogas is nothing new, but Bio-CNG is and has come on the agenda only recently due to developments in technology and market. Biogas has 50% Methane and thus has to be upgraded, for use in automotives, to above 90% for technical and economic reasons. Also some gas cleaning is required to remove sulfur. This has been achieved successfully, technically and commercially only recently. One can now produce CNG at 50% of the price of Gasoline in the US Several commercial projects for self use by the producers have been launched.
To reassure the skeptics, let me also reproduce the cuttings from a news-letter (Bio-Master) on the subject, which shows how active and popular the subject is in many countries:
BIOGAS FROM SEWAGE TREATMENT PLANT TO POWER DELHI BUSES
August 2012 Ambitious as it may sound, but Delhi plans to run its buses on biogas. In collaboration with the Swedish government, the Union Ministry of New and Renewable Energy plans to set up a biogas plant inside Kesopur Sewage Treatment Plant (STP) complex in West Delhi.
INDIA TO TEST THE BIO-CNG PRODUCED FROM BAGASSE IN A COMMERCIAL VEHICLE
February 2013 Under instructions from the Union Ministry for New and Renewable Energy (MNRE), Pune-based Automotive Research Association of India is expected to test the bio-CNG produced from bagasse and its use in operating a commercial vehicle. ENOC SIGNS AGREEMENT WITH DUBAI MUNICIPALITY TO PRODUCE CNG FROM WASTE FOR automotive use
February 2013 Emirates Gas LLC (EMGAS), a subsidiary of Emirates National Oil Company (ENOC), has signed a Memorandum of Understanding with Dubai Municipality to treat land and sewage waste to generate compressed natural gas (CNG). EMGAS is now setting up an advanced facility to convert waste to bio-methane, from what is currently being flared, and then compress it into compressed natural gas that will be used as an automotive green.
FIRST ECO-BUS ENTERS SERVICE IN ZALAEGERSZEG (HUNGARY)
August 2012 The first eco-bus of the local public transport company entered service on 27 June. It is fuelled by biomethane, which is derived from the local sewage treatment plant. This action is part of a series of measures which aim to turn Zalaegerszeg into a sustainable town.
TURKU AIMS TO USE MORE BIOGAS BUSES (FINLAND)
October 2012 The city of Turku pledges to use the growing share of biogas to power its city buses. The aim is to make the bus transport within the city as environmentally friendly as possible.
FIRST ECO-BUS ENTERS SERVICE IN ZALAEGERSZEG (HUNGARY) The first eco-bus of the local public transport company entered service on 27 June. It is fuelled by biomethane, which is derived from the local sewage treatment plant. This action is part of a series of measures which aim to turn Zalaegerszeg into a sustainable town.
Ministry of Fuel (MFNRE) in India has approved about 15 projects subsidising up to 50% of the equipment cost of Bio-CNG installations. Local Government of New Delhi has decided to switch to Bio-CNG by producing Biogas from its solid waste facilities and get almost free fuel. Nothing is free though, the amortization costs and operating expenses would still yield a fuel cost saving of 50%. All public transport facilities and projects almost anywhere suffer from high cost issues not sufficiently covered under an affordable tariff. It is said that the newly established Metro-Bus project in Lahore also suffers from the same issue. However, Lahore generates a lot of solid and liquid waste and there should be ample agro-biomass around Lahore to be able to generate enough Bio-CNG at 50% of the Diesel prices. I hope the CM Punjab somehow reads it or get to know about it. Similarly, Karachi or for that matter all major cities can afford a public transport system under a cheaper and locally available fuel, in a country which calls itself an agricultural country. Reportedly, more than 35 CNG Buses procured by the local government of Karachi are in the docks, although for other than cost reasons. But improved economics and lesser fuel costs certainly help.
Although, urban area CNG stations may not be able to benefit from Bio-CNG(except where local government develop projects from organic waste), CNG stations on the highways passing through rural areas can certainly install Bio-CNG facilities. A Bio-CNG plant consumes a lot of space for biogas generation plant, although the same compression facilities as are already available in conventional CNG would be required for compressing and filling Bio-CNG. In Punjab and Sindh, there should be a large number of existing CNG stations that could benefit from this concept. Capital investments of about Rs 10 Million have been estimated for installing Biogas facilities at the existing CNG pumps in rural areas.
A wide variety of Biomass is available; Household and Municipal Solid waste , sewerage and waste water, agricultural, forestry and plant residue. To my knowledge, there is no single location or facility in Pakistan, where solid waste is hygienically and scientifically disposed off, except for some recycling activity self-sustained by commercial recyclers. In most countries particularly in Europe, hitherto, MSW had been incinerated, but now trend is changing towards gasification of solid waste. Waste heat was fed into heat exchangers to supply to the district heating systems or heat utilised in other applications. Incineration has become out of fashion due to environmental reasons as well. Increasingly solid waste is being disposed in Landfills which invariably produce Biogas.
In Pakistan, a number of studies and efforts have been undertaken in the past to generate electricity from Municipal Solid Waste (MSW), but could not succeed due to a variety of reasons including poor economics and comparatively lower Calorific value of Pakistani MSW. Most, in fact all cities throw their MSW in uncovered waste dumps spreading squalor and disease in adjoining areas. Often, it is shamefully and carelessly burnt in the open very close to the residential areas. Any body who has crossed the Korangi bypass at night would know how dangerous this activity is. Bio-gasification and Bio-CNG may improve the economics of collection and disposal of MSW in most communities, especially major cities.
Villages and Rural Centers can replace diesel from their diesel engines of the tube wells. Also, tractors could be switched to Bio-CNG. Where Biomass should be used for producing electricity or where it should be used for Biogas for cooking or for Bio-CNG, would depend on time and space issues and choices of the stakeholders. No policy can be announced promoting or proscribing a certain use, although it is clear that in case of Bio-CNG, the alternative or opportunity cost is much higher, ie Bio-CNG is replacing expensive gasoline and diesel, while there are cheaper options to produce electricity than from Biomass.
Enterprise and innovation is augmented by the economics. A textile entrepreneur in Punjab is reportedly buying several hundred Buffaloes (which in addition to Milk) to provide Gober fuel which would generate Biogas which in turn would be used in electricity generation for his adjacent Textile Mill. The Gober generated Biogas would also be burnt in their Boilers.
Certainly, Bio-CNG would not be a panacea for our energy problems or a one-size-fit-all solution. Cheaper Oil and gas used to be such a panacea and a solution, but no more. But one could expect that a significant portion of CNG demand could be met through Bio-CNG. Localised and segmentised solutions for a variety of users and market conditions may have to be implemented by the private sector mostly, although Government can guide, facilitate and afford some demonstration and early project subsidies. These kinds of solutions such as Bio-CNG, apart from being economic and affordable, also add to our energy security. Imagine what would happen, if oil import facilities or market suffer some kind of blockade or discontinuity, or the law and order problem, affecting the inter-city transport. Biogas is locally produced as would be Bio-CNG.
Concluding, Bio-CNG appears to be an interesting and viable alternative to conventional CNG. Bio CNG should be allowed to grow in an unhindered market environment. Except for quality and safety issues, there should be no regulation, of price or otherwise. It should be the individual CNG dealer's choice weather and where he should invest to produce and sell CNG. However, a government policy would be required to reassure potential investors and the existing CNG dealers that their investment and efforts would not be wasted and that at some point in time, government may start discouraging out. No policy is for ever. Circumstances keep changing and new challenges and issues are to be handled. However, sufficient time and opportunity should be made available before a change of policy stance to enable the investors to recoup their investments. Fortunately, in the case of Bio-CNG, Bio-gasification facility would always have many other alternative markets and usages.
Bio-CNG should be allowed to grow in an uncontrolled market environment. Except for quality and safety issues, there should be no regulation, of price or otherwise. It should be the individual CNG dealer's choice weather and where he should invest to produce and sell CNG.
====================================================
No of Livestock=56.9 Million
Live stock Biomass generation=1 Mn Tons/day
Number of Large Dairy Farms=30,000 (avg 200 Cattles)
MSW =55000 tons/day
Crop residue= 225000 tons/day
Annual Biogas (Bio-methane) potential=1.6 TCF/yr
Pakistan Ngas Production=1.4 TCF/yr
Existing Short Fall= 1 TCF/yr
CNG consumption=0.164 TCF/yr
LNG projects =0.146 TCF/yr (25 Billion USD imports)
OR Electricity Potential from Biogas =3800 MW
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Source: Author's Estimates
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DAIRY FARM HERD SIZE AND BIOGAS & ELECTRICITY OUTPUT
========================================================
No of animals Gas out put Tot.Gas Tot.Electr Power Profit
number CM/animal/d Mbtu/yr kWh/yr KW Rs/yr
========================================================
5000 2.4 147000 14700000 2940 14700000
3000 2.4 88200 8820000 1764 8820000
2000 2.4 58800 5880000 1176 5880000
1000 2.4 29400 2940000 588 2940000
500 2.4 14700 1470000 294 1470000
200 2.4 5880 588000 117.6 588000
======================================================
Source: http://www.brecorder.com
Harvesting flies for animal feed wins innovation prize
A South African company has won the Innovation Prize for Africa (IPA) for developing a method of creating livestock feed from maggots.
AgriProtein Technologies beat ten other finalists from across the country and was awarded US$100,000.Jason Drew, cofounder of the company, explained the process “ After allowing flies to lay eggs in the bio-waste, the resultant larvae, or maggots, are harvested and dried before being mixed with carbohydrates and starch to create food for chickens, crayfish, abalone and pigs.”
Drew said his company is already at a commercial production stage in order to provide farmers with affordable animal feed protein and the prize money would enable to expand to the rest of Africa.
“We are honoured by this remarkable recognition. We are passionate about expanding our business to recycle more waste nutrients and supply a natural protein to feed farm animals… helping sustainably feed our continent…this is an African contribution to sustainable agriculture for our planet,” he said.
The IPA was founded by the African Innovation Foundation (AIF) and the United Nations Economic Commission for Africa, focusing on building Africa’s capacity by investing in local entrepreneurship.
Source: allaboutfeed
Biogas: Hope for Pakistan
What is Biogas?
Biogas is naturally produced when any organic matter decomposes under anaerobic conditions (in the absence of oxygen).
Biogas is naturally produced when any organic matter decomposes under anaerobic conditions (in the absence of oxygen).
The gas consists mainly of methane (CH4) and carbon dioxide (CO2) in approximately 3:2 ratio.
Methane is the important component, as it is a highly flammable gas that can be utilized as fuel for cooking, lighting, water heaters and, if the sulphur is removed, it can be used to run biogas-fuelled generators to produce electricity.
Biogas can be produced under controlled circumstances in specially designed biogas digesters.
There are many types of digesters that are being used throughout the world. In countries such as Germany, biogas technology is highly advanced and applied primarily to produce green electricity in the megawatt range. In other developing countries such as India and China, a more basic technology is used to provide energy primarily for cooking purposes. India for instance, has more than a million digesters producing all the cooking energy for thousands of villages using human (sewerage) and animal (manure) waste in the process. One of the major spin-offs of using a biogas digester, is that the spent material is in the form of organic compost that can then be used to increase the yield of planted crops.
The Benefits of Biogas
The use of biogas is practically limitless.
As a combined sewerage management/biogas producing system, any new house, guest house, lodge, development, golf estate, clinic, hotel, etc. can install a biogas digester system. It can be their primary sewerage system, or a source of alternative and sustainable energy in the form of biogas. The digestate can be applied directly as organic compost, or the water can be recycled through a wetland.
Commercially biogas digester systems can be installed at dairies, piggeries, chicken farms, abbotoirs or any other type of industry where waste containing organic material is produced, to generate green sustainable electricity.
A biogas digester has the following advantages:
It produces methane gas that can be used for cooking purposes, lighting, water heating and to generate electricity
It digests organic waste (from the kitchen, garden, sewerage, animal manure, etc.)
It prevents methane gas from entering the atmosphere (methane gas is 20 times more harmful to the environment than CO2)
It produces organic compost as waste product (in liquid, slurry or solid form)
Who Can Use Biogas?
The use of biogas is practically limitless.
As a combined sewerage management/biogas producing system, any new house, guest house, lodge, development, golf estate, clinic, hotel, etc. can install a biogas digester system. It can be their primary sewerage system, or a source of alternative and sustainable energy in the form of biogas. The digestate can be applied directly as organic compost, or the water can be recycled through a wetland.
Commercially biogas digester systems can be installed at dairies, piggeries, chicken farms, abbotoirs or any other type of industry where waste containing organic material is produced, to generate green sustainable electricity.
A biogas digester has the following advantages:
It produces methane gas that can be used for cooking purposes, lighting, water heating and to generate electricity
It digests organic waste (from the kitchen, garden, sewerage, animal manure, etc.)
It prevents methane gas from entering the atmosphere (methane gas is 20 times more harmful to the environment than CO2)
It produces organic compost as waste product (in liquid, slurry or solid form)
Who Can Use Biogas?
SMALLHOLDINGS:
The ideal application for the Puxin Family Size Digester (10m3 digester) is for smallholdings, especially if there is some access to animal manure. Adding animal manure over and above the household sewerage, greatly increases the production of methane gas. Practical use of the gas is primarily for cooking purposes, but the gas can also be used in the Puxin biogas water heater, biogas lights and to generate (standby) electricity by using a biogas generator.
LARGER SETUPS:
The next market segment is for larger setups such as guest houses, schools, clinics, or small farms where multiple units of the 10m3 digester are used. Sizing of the system is directly proportional to the amount of material fed into the digester, whether the system is designed primarily as a sewerage system or for the production of biogas. The amount of methane produced is dependent on the amount of gas producing material fed into the digester, limited to an approximate maximum of 5m3 of gas per 10m³ digester per day.
COMMERCIAL FARMING CONCERNS:
Dairies, pig farms and chicken farms that produce large quantities of manure fall into this category. Implementing a biogas digester system for these concerns could potentially be of enormous financial benefit for such ventures. Under normal circumstances the huge amounts of manure produced is more of a liability than an asset and either gets dumped or sold to composting companies for a nominal fee. By installing a biogas digester system, the manure now becomes a major asset, able to produce practically free energy. This energy in the form of biogas can now be utilized to generate electricity, heat water, provide lighting or could be used for cooking purposes by the personnel on site.
For this type of application Biogas SA will install their large 100m3 Puxin digester in conjunction with multiple gas holders. Biogas SA can supply and commission any size of biogas generator from a small 5kVA to very large 500kVA unit, depending on client's requirements.
MUNICIPAL SEWERAGE WORKS:
The Puxin technology is ideally suited to design and construct major sewerage works. Biogas technology can be used to replace existing technology and practices at our municipal sewerage works, not only providing a better way to deal with raw sewerage, but providing free energy in the process.
Due to various reasons, a large number of our municipal sewerage works have become inefficient, is starting to cause serious pollution problems and is contributing to large scale contaminations of our precious water resources in South Africa. Commissioning biogas systems to replace the failing sewerage works has the potential to change this potentially disastrous situation into a win-win situation for all parties concerned.
The cost of such biogas installations could be offset by claiming international carbon credits, the biogas generated could be used to generate electricity that could either be sold back to the grid or be used locally and the spent slurry could be sold off as organic compost. The major advantage to the environment is that the eventual effluent produced, will be of such a standard that it could in actual fact improve the quality of the water of the rivers it gets pumped into!
Biogas SA with its association with The Shenzhen Puxin Science and Technology Company of China, is in a position to provide the full spectrum from design to implementation of fully functional, technologically advanced, biogas digester systems for the management of large scale sewerage works. This is applicable not only for municipal sewerage works, but also for any large scale residential developments, housing estates, golf estate developments, etc.
PUBLIC SECTOR INSTITUTIONS:
Biogas SA can provide a service to all kinds/levels of public sector institutions such as schools, clinics, national parks, etc. and can be particularly effective if we could get involved during the design stage of such projects. It is a lot more cost effective to incorporate a biogas digester as part of the initial design, rather than doing a retro-fit at a later stage.
WASTE RECYCLING PLANTS:
Any form of organic waste can be used as fuel for a biogas digester to produce methane. This introduces a whole new market not previously addressed by traditional digesters due to the difficulty of removing the solid spent waste from the digester. The Puxin digester has a large fiberglass reinforced dome that can easily be removed (no danger of trapped gas), giving easy access to clean the digester out and re-load with fresh material.
This means that any type of organic waste material generated such as agricultural waste, restaurant/hotel food waste, municipal garden waste, waste from fresh produce markets, abattoir waste and any other waste one can think of as long as it is organic in nature. It can potentially be a solution to the water hyacinth problem!
Tapping into free energy in the form of methane gas by feeding organic waste into a biogas digester is one of the most practical and cost effective ways to generate alternative, sustainable and environmentally friendly energy for all in South Africa.
The ideal application for the Puxin Family Size Digester (10m3 digester) is for smallholdings, especially if there is some access to animal manure. Adding animal manure over and above the household sewerage, greatly increases the production of methane gas. Practical use of the gas is primarily for cooking purposes, but the gas can also be used in the Puxin biogas water heater, biogas lights and to generate (standby) electricity by using a biogas generator.
LARGER SETUPS:
The next market segment is for larger setups such as guest houses, schools, clinics, or small farms where multiple units of the 10m3 digester are used. Sizing of the system is directly proportional to the amount of material fed into the digester, whether the system is designed primarily as a sewerage system or for the production of biogas. The amount of methane produced is dependent on the amount of gas producing material fed into the digester, limited to an approximate maximum of 5m3 of gas per 10m³ digester per day.
COMMERCIAL FARMING CONCERNS:
Dairies, pig farms and chicken farms that produce large quantities of manure fall into this category. Implementing a biogas digester system for these concerns could potentially be of enormous financial benefit for such ventures. Under normal circumstances the huge amounts of manure produced is more of a liability than an asset and either gets dumped or sold to composting companies for a nominal fee. By installing a biogas digester system, the manure now becomes a major asset, able to produce practically free energy. This energy in the form of biogas can now be utilized to generate electricity, heat water, provide lighting or could be used for cooking purposes by the personnel on site.
For this type of application Biogas SA will install their large 100m3 Puxin digester in conjunction with multiple gas holders. Biogas SA can supply and commission any size of biogas generator from a small 5kVA to very large 500kVA unit, depending on client's requirements.
MUNICIPAL SEWERAGE WORKS:
The Puxin technology is ideally suited to design and construct major sewerage works. Biogas technology can be used to replace existing technology and practices at our municipal sewerage works, not only providing a better way to deal with raw sewerage, but providing free energy in the process.
Due to various reasons, a large number of our municipal sewerage works have become inefficient, is starting to cause serious pollution problems and is contributing to large scale contaminations of our precious water resources in South Africa. Commissioning biogas systems to replace the failing sewerage works has the potential to change this potentially disastrous situation into a win-win situation for all parties concerned.
The cost of such biogas installations could be offset by claiming international carbon credits, the biogas generated could be used to generate electricity that could either be sold back to the grid or be used locally and the spent slurry could be sold off as organic compost. The major advantage to the environment is that the eventual effluent produced, will be of such a standard that it could in actual fact improve the quality of the water of the rivers it gets pumped into!
Biogas SA with its association with The Shenzhen Puxin Science and Technology Company of China, is in a position to provide the full spectrum from design to implementation of fully functional, technologically advanced, biogas digester systems for the management of large scale sewerage works. This is applicable not only for municipal sewerage works, but also for any large scale residential developments, housing estates, golf estate developments, etc.
PUBLIC SECTOR INSTITUTIONS:
Biogas SA can provide a service to all kinds/levels of public sector institutions such as schools, clinics, national parks, etc. and can be particularly effective if we could get involved during the design stage of such projects. It is a lot more cost effective to incorporate a biogas digester as part of the initial design, rather than doing a retro-fit at a later stage.
WASTE RECYCLING PLANTS:
Any form of organic waste can be used as fuel for a biogas digester to produce methane. This introduces a whole new market not previously addressed by traditional digesters due to the difficulty of removing the solid spent waste from the digester. The Puxin digester has a large fiberglass reinforced dome that can easily be removed (no danger of trapped gas), giving easy access to clean the digester out and re-load with fresh material.
This means that any type of organic waste material generated such as agricultural waste, restaurant/hotel food waste, municipal garden waste, waste from fresh produce markets, abattoir waste and any other waste one can think of as long as it is organic in nature. It can potentially be a solution to the water hyacinth problem!
Tapping into free energy in the form of methane gas by feeding organic waste into a biogas digester is one of the most practical and cost effective ways to generate alternative, sustainable and environmentally friendly energy for all in South Africa.
What Do We Use To Produce Biogas?
THE PUXIN DIGESTER:
Biogas SA is the sole licensee for South Africa of the Shenzhen Puxin Science and Technology Company (Puxin) of China. Puxin has developed over a period of 20 years a unique, patented hydraulic biogas digester that has eliminated all the disadvantages and enhanced the advantages of the more traditional fixed and floating dome type digester designs. As acknowledgement of its technology and contribution to promoting efficient alternative energy resources, Puxin was awarded the prestigious Global Top Ten Investment Scenarios to Apply New Technologies for Renewable Energy Utilization BlueSky Award in 2006, initiated by the United Nations Industrial Development Organisation.
The Puxin digester basically consists of a belly, a neck, the plastic gas holder or dome, an inlet and an outlet. One of the main features of the digester is the fact that it basically functions as a hydraulic system. The entire digester is flooded with water, with the water at the same level in the inlet, digester neck and outlet. The fact the decomposition of the material now takes place under water, creates the ideal anaerobic conditions so critical for the creation of methane gas. The added advantage of the water is that it is also responsible for creating the constant pressure under which the biogas is available in this type of digester.
As the biogas is produced in the bottom of the digester belly, it rises upwards and is eventually caught in the dome. As the volume of gas increases, it starts to replace the water in a downward direction. The resulting upward pressure of the replaced water ensures that the collected biogas in the dome is always under constant pressure (up to 8 bar). The fact that the gas is always available at the same constant pressure is a major advantage for the efficient running of most gas appliances. It is practically impossible to run a generator for instance, if the gas feeding the generator is not available under constant pressure; the generator will simply cut out every time the pressure drops.
Another advantage of the Puxin design, is the ease with which the digester can be emptied out. Because it is so easy to clean, any type of organic material can be used as feeder material. Where it is not practical to empty a digester (fixed dome type), only material such as manure that leaves now solid residuals after the decomposition process is complete, can be used as feeder material. Organic waste such as leaves, straw, grass, etc do not decompose to the same extent as manure and will always leave solid waste after decomposition. This spent material needs to be removed from the digester before the digester can be reloaded with new material. The light weight Puxin digester dome can easily be removed by two people, making it a practical system suitable to use organic waste as feeder material. This is a major advantage for applications where manure is not available in the necessary quantities, but enough organic material is available.
Source: Dicla Training CenterTHE PUXIN DIGESTER:
Biogas SA is the sole licensee for South Africa of the Shenzhen Puxin Science and Technology Company (Puxin) of China. Puxin has developed over a period of 20 years a unique, patented hydraulic biogas digester that has eliminated all the disadvantages and enhanced the advantages of the more traditional fixed and floating dome type digester designs. As acknowledgement of its technology and contribution to promoting efficient alternative energy resources, Puxin was awarded the prestigious Global Top Ten Investment Scenarios to Apply New Technologies for Renewable Energy Utilization BlueSky Award in 2006, initiated by the United Nations Industrial Development Organisation.
The Puxin digester basically consists of a belly, a neck, the plastic gas holder or dome, an inlet and an outlet. One of the main features of the digester is the fact that it basically functions as a hydraulic system. The entire digester is flooded with water, with the water at the same level in the inlet, digester neck and outlet. The fact the decomposition of the material now takes place under water, creates the ideal anaerobic conditions so critical for the creation of methane gas. The added advantage of the water is that it is also responsible for creating the constant pressure under which the biogas is available in this type of digester.
As the biogas is produced in the bottom of the digester belly, it rises upwards and is eventually caught in the dome. As the volume of gas increases, it starts to replace the water in a downward direction. The resulting upward pressure of the replaced water ensures that the collected biogas in the dome is always under constant pressure (up to 8 bar). The fact that the gas is always available at the same constant pressure is a major advantage for the efficient running of most gas appliances. It is practically impossible to run a generator for instance, if the gas feeding the generator is not available under constant pressure; the generator will simply cut out every time the pressure drops.
Another advantage of the Puxin design, is the ease with which the digester can be emptied out. Because it is so easy to clean, any type of organic material can be used as feeder material. Where it is not practical to empty a digester (fixed dome type), only material such as manure that leaves now solid residuals after the decomposition process is complete, can be used as feeder material. Organic waste such as leaves, straw, grass, etc do not decompose to the same extent as manure and will always leave solid waste after decomposition. This spent material needs to be removed from the digester before the digester can be reloaded with new material. The light weight Puxin digester dome can easily be removed by two people, making it a practical system suitable to use organic waste as feeder material. This is a major advantage for applications where manure is not available in the necessary quantities, but enough organic material is available.
Camel Farming
When discussing milk and lactation in general, two aspects must be taken into account. The first is the amount of milk produced per day and per lactation period. The other aspect, which is as important, is the type of milk produced. Animals living in cold areas or in the sea need a different quality of milk from those living in hot areas; this applies also to fast-growing animals as compared with slow-growing animals (Yagil & Etzion, 1980).
This section will deal with the lactation, milking and amount of milk produced.
The mainstay of the desert nomad's food is camels' milk, which is consumed fresh or when just soured (Mares, 1954, Gast et al.1969). Data on the actual amount of milk produced by camels are not very accurate for judging the milk-giving capabilities of camels.
The mainstay of the desert nomad's food is camels' milk, which is consumed fresh or when just soured (Mares, 1954, Gast et al.1969). Data on the actual amount of milk produced by camels are not very accurate for judging the milk-giving capabilities of camels.
Calves must be allowed to drink; therefore, the herder and his family must share with the calf the milk produced by the herd. How much the calf drinks certainly varies with its size, age, and health. The amount of grazing and water available to the camel will also determine the amount suckled, and the total produced.The camel, like the cow, has a four-quartered udder. It is firmly suspended from the abdomen, without deep cuts (Sharma, 1963) (Photo 4). There are four teats, each having two orifices.
China
The two-humped Bactrian camel is used mostly as a working animal (Dong Wei, 1979). The lactation period is 14–16 months, and the amount of daily milk production averages 5 kg per animal; although some animals can give as much as 15–20 kg per day. Normally, only about 2 kg are milked; the rest is suckled by the calf.
Russia
Milking capabilities of the Bactrian, the dromedary, and the hybrid of these two types of camels were examined (Kheraskov, 1955, 1961, 1965; Lakosa & Shokin, 1964; Dzhumagulov, 1976). The dromedary gave more milk than the Bactrian or the hybrids (Table 2). The hybrid - Kazakh - gave more milk than the hybrid Turmein. The lactation period was 18 months. Most of the milk was produced in the first seven months of lactation, from spring, throughout summer, until Autumn. This was correlated with the availability of fodder. Grazing in Winter is difficult, because of snow. The second lactation yield was far greater than the first, and in each following lactation more milk is produced. The estimated milk yield between the third and sixth months of lactation was 879– 1 572 kg (Kulaeva, 1979). Slightly more milk was received from the back-quarter, 56.4 percent to 43.6 percent from the forward-quarters. From the sixth month of pregnancy the amount of milk declined.
With good stall feeding the same amounts of milk were received as with grazing animals. This would be of great importance if a steady and balanced diet could be supplied to the animals throughout the year.
When the animals are hand-milked the milker stands on one leg and balances the milking bowl on his bent left leg. The left hand holds the bowl, while the camel is milked with the right hand. Another method is to tie the bowl around the milker's neck so it hangs low enough to be held while the camel is being milked. Camels have successfully been machine milked. Liners of 18.56 mm diameter and 56 mm length are recommended for the Bactrian and liners of 20.6 mm diameter and 90 mm length are recommended for the dromedary (Baimukanov. 1974). The animals were gradually changed from hand to machine milking in the presence of their calves. The cell-count of milk of hand-milked camels was lower than that of machine-milked camels (Kospakov, 1976).
In the vast dry areas between the Caspian Sea and the Balkash Lake the camel is, and can be, of great nutritional importance. In Kazakstan, milk and milk products account for up to 90 percent of the daily staple diet. The camel is the most important provider of milk. Thirty-seven percent of all milk comes from the camel; 30 percent from sheep; 23 percent from the Yak and only 10 percent from cows.
New World Camels
Little is known about the milk production of these members of the camel family. The alpaca, when kept on good pasture, can produce up to 0.5 kg of milk daily (Novoa, 1970).
Horn of Africa
In the Horn of Africa, milking of camels is not only an act of work, but has become an integral part of the local culture and heritage. Only boys, unmarried women or ritually clean men are allowed to milk the animals (Hartley, 1979). No treatment of the milk is allowed. The milk is either consumed fresh or when just soured. In some tribes the herdboys subsist on camel milk alone. They drink water only after the camels are watered. Two teats are left for the calf, while the other two are milked-out for the tent dwellers. These latter two teats are tied up with soft bark fibres. The colostrum is not drunk, but is either given to the calf although it is thought to be bad for the young camel (Field, 1979), or spilled onto the ground. This certainly represents a bad practice since the colostrum contains large amounts of absorbable antibodies.
The camels are milked twice a day; before dawn and at night. The average milk production is about 1 800 kg, i.e.: 9 kg per day.
Country
|
Daily
|
Lactation yield
|
Lactation length
(months)
|
Calculated yield
per 305 day
|
Reference
|
|
average
|
max
|
|||||
China-Bactrian
|
5
|
15–20
|
1 254
|
Dong Wei, 1981
|
||
USSR-Bactrian
|
735
|
Lakosa & Shokin,
|
||||
-
Hybrid-Kazak
|
1 305
|
1964 "
|
||||
-Hybrid-Turkmen
|
981
|
"
|
||||
Dromedaries
|
||||||
China
|
7.5
|
3 300
|
16–17
|
2 288
|
Ensminger, 1973
|
|
USSR
|
2 003
|
Lakosa & Shokin,
|
||||
USSR
|
8.1
|
19
|
4 388
|
1964 "
|
||
Horn
of Africa
|
9
|
1 800
|
Hartlet, 1979
|
|||
N.
Kenya
|
4
|
12
|
"
|
|||
N.
Kenya
|
50
|
1 897
|
Field, 1979
|
|||
Ethiopia
|
5–13
|
1 872–2 592
|
12–18
|
1 525–3 965
|
Knoess, 1977
|
|
Somalia
|
5
|
1 950
|
13
|
1 525
|
Rosetti et al., 1955
|
|
Libya
|
8.3–10
|
2 700–4 000
|
9–16
|
2 532–3 050
|
C.E.F. Li, 1977
|
|
Algeria
|
4
|
10
|
Gast et al., 1969
|
|||
Tunisia
|
4
|
12
|
1 220
|
Burgmeister, 1974
|
||
India:
|
||||||
good
feeding
|
6.9
|
18.2
|
3 105–8 190
|
15
|
2 105–5 551
|
Rao, 1974
|
bad
feeding
|
1 360
|
Yasin et al., 1957
|
||||
desert
|
6.8
|
9.1
|
2 430–4 914
|
18
|
1 373–2 776
|
Rao, 1974
|
Pakistan:
|
8.0
|
13.5
|
13 560–3 660
|
1 068–4 118
|
Yasin et al., 1957
|
|
good
feeding
|
9–13.6
|
20.5
|
2 727–3 636
|
16–18
|
3 150–4 148
|
" "
|
bad
feeding
|
4
|
1 364
|
1 220
|
" "
|
||
Pakistan:
|
6.7.10
|
2 700–3 600
|
9–18
|
2 044–3 050
|
Leupold, 1978
|
|
good
feeding
|
15–35
|
5 475–12 775
|
12
|
4 574–10 675
|
Knoess, 1979
|
|
desert
|
8.10
|
2 920–3 650
|
12
|
2 440–3 050
|
Knoess, 1979
|
|
Egypt
|
3.5–4.5
|
1 600–2 000
|
1 068–1 373
|
El-Bahay, 1962
|
||
Israel
|
||||||
+
water
|
6.0
|
Yagil et al., 1980b
|
||||
-
water
|
6.2
|
" "
|
||||
Weaning is carried out when the calves are 9–11 months old. A leather band with protruding thorns is placed on the calf's head in such a way that the dam is pricked every time the calf attempts to suckle; the dan thus quickly moves away.
North Kenya
In North Kenya the camels produce far more milk than the local cows. The Sakuye camel produces an average of 4 kg milk daily with a maximum of 12 kg. The cow produces 0.5–1.5 kg per day. Camels lactate for about a year. In areas with only one rainy season lactation finishes at the end of the dry season; this is thought to be caused by the shortage of feed during this period.
In areas of northern Kenya, where the nomads subsist almost entirely on camel milk, there are two rainy period. Field (1979a and 1979b) reported lactation studies lasting three lactations. The duration of lactation was 47–67 weeks. Lactation ended 4–8 weeks following conception. Daily milk production reached 21 kg in the first week, declining to 4.8 kg in the 16th week of lactation. There was an average daily milk yield of 13 kg for the first 10 weeks (1.8–50.2 kg) and 3 kg for the remainder of the lactation. Total production averaged 1 897 kg per animal. In the lactation studies the lowest milk yields were those given by camels without calves. These animals also had much shorter lactation periods, even though they were milked 5–7 times a day. Four milkings per day yielded more milk than twice a day milkings: seven liters compared with six (Evans and Powys, 1979; Shalash, 1979).
Ethiopia
The camel is known to be capable of producing large quantities of milk under extensive and intensive management (Knoess, 1979). Knoess rightly stresses the fact that as the camels are not intensively milked, but some milk is left for their calves, the exact amount is difficult to assess. Milk trials in the Awash Valley of Ethiopia were carried out for six days in various stages of lactation (Knoess, 1976). As suckling stimulus is an integral part of milk production (Yagil et al., 1975), it is obvious that in the short period of hand-milking the maximum milk producing capabilities were not fully exploited. Even so, eight liters in two milkings, or 2 470 kg over 305 days were obtained. The daily average for twice-a-day milking was estimated at 7 kg. These animals grazed on irrigated pastures. Under rainfed conditions, 13 kg per day can be milked (Knoess, 1979). It was found that some days the camels were milked 6–8 times a day, while other days they were not milked at all. This certainly would make the milk supply lower than if the animals were milked regularly each day. In the dry season the milk yield was about half that of the rainy season. This could be due to the lack of feed or to advanced stages of pregnancy (Lakosa, 1964).
Somalia
The lactation period is between 8–18 months (Mares, 1954a). The length of lactation depends on when the lactating dam is remated. The average daily yield in milk is 5 kg with a total yield of 1 950 kg. The amount of milk drunk by the calf is regulated by tying up one or more teats (Mares, 1954a). The amount the calf is allowed is determined by its needs and the milking capacity of the mother. Camels are milked twice a day; just after sunrise and at least two hours after sunset. Calves run with their mothers but are penned separately at night. From the age of six weeks they graze. When calves have finished suckling the amount left for consumption by the tent dwellers can vary from 1 to 4 kg (Epstein, 1970).
If a calf dies, the dam dries up if milking is not stimulated (Mares, 1954a). For this a foster calf or conditioning of the mother is necessary. Often arranging for the dam to see the skin of her dead calf is enough to stimulate let-down of milk. Fostering is done in three ways: (1) The foster calf is covered with the skin of the dead calf and allowed to suckle until the milk is flowing and the dam can be hand-milked. (2) The calf is tied down in front of the foster-mother, a rope being tied from the calf to the mother's muzzle. (3) The nostrils, ears or anus of the foster-mother are compressed with a special clamp. When the clamp is released, and the pain thus removed, the calf is presented for suckling. This is usually anough for the dam to allow the foster-calf to suckle.
In all cases the calf drinks from its own mother as well as from the foster-mother.
Algeria
The nomads of the Ahaggar in the Sahara depend on milk to given them a balanced diet (Gast et al., 1969). They have a saying “water is the soul; milk is life”, and hungry people say “I've lost the taste of milk”. Of course the camel is only one of the providers of milk. Goats, sheep and cows supply milk and milk products. The lactating camel produces 4–5 kg/day, on good pasture, for the first three months. A good milker can even provide up to 10 kg a day. When the udders are full the animals are milked three times a day, otherwise their swaying teats hinder their walking. After the third month of lactation the yield averages about 2 kg per day. The bad milkers dry off very quickly. It is therefore accepted that one camel is necessary to provide the requirements of one family. The camel herders' only source of food is camel milk.
The camels are tied down during the night and the camels' udders are covered with nets to prevent the young from suckling. The first milking takes place before dawn. The young calves are allowed to suckle for about one or two minutes. This is time for the milk to let-down. The calves are pulled away and the dam then milked for the tent dwellers. At twilight the camels are returned to the camp, and milked again after allowing the calves to suckle for a few minutes.
India
The geographical distribution of camels (dromedaries) in India, is in the States of Gujorat, Haryana, Maharashtra, Madhya, Pradesh, Punjab, Rajasthan and U.P. (Rao et al., 1970). The females calve for the first time at the age of 4 years. They lactate for 8–18 months. The amount of milk for the calf, and the amount that is milked, is regulated by tying up the teats to prevent the calf from suckling. The camels are milked twice a day. The daily milk production is between 2.5–6 kg, but often 15 kg per day is milked. Lactation yields range from 2 000 kg (Gohl, 1979) to 2 700–3 600 kg (Rao et al., 1970) under good feeding conditions, to about 1 360 kg, when feed supplies are poor (Yasin and Wahid, 1957).
Pakistan
The Arabian camel is found mainly in West Pakistan (Yasin & Wahid, 1957). Length of the lactation varies from 270–540 days; daily milk yields of 15 to 40 litres were recorded (Knoess, 1977). The total milk yield ranges from 1 350–3 600 kg. The lower milk yields were found in the areas where feed supplies are poor and under desert conditions. When the camels were well fed, there was an average milk yield of 10–15 kg per day (Yasin and Wahid, 1957). As much as 22 kg a day were obtained from some camels. In the areas with poor feeding the daily average was 4 kg. The heavy Pakistani camels produced up to 35 kg per day (Knoess, 1979). The desert camels gave more milk than the animals getting poor feed. These animals were milked twice daily.
Egypt
With good feeding a daily milk production of 10–15 kg was obtained (Shalash, 1979) giving a yield of approximately 3 000–4 000 kg per lactation. Daily yields of 22 kg have been recorded. Where feeding was precarious the daily production was only 4 kg, with a total production of 1 500 kg. These later data are similar to those presented by El-Bahay, 1962.
Israel
No actual recordings of milking have been made. Estimates of milk production range from 7 to 15 kg daily. Lactation periods vary from 9–18 months. In order to establish the total amount of milk produced by the lactating camel, the milk yield was measured indirectly (Yagil & Etzion, 1980). This method is based on firts marking the calves' blood with radioactive water. The calves were not allowed access to any drinking water as this would have made milk determinations impossible. The mothers were allowed drinking water only once a week for an hour, from the beginning of spring until the end of summer. The results show that there was a slight increase in milk yields as lactation progressed (5.7 to 6.2 kg). No decline was found when the animals were dehydrated. These data do not give the full potential of the camel as, in fact, what was measured was the calves' need for water. The calves ate the same feed as their mothers. They started eating within the first month of birth. Not withstanding this fact, it is quite clear that the feed demand of the calf is fairly large. In addition, research was carried out using the same diet throughout the year to eliminate nutritional factors affecting quantity and quality of milk. The natural grazing available to camels changes from winter to spring and in the summer the changes are even more drastic, in quantity and quality. With a decline in quantity the calves would tend to take more from their mothers than when the feeding is plentiful.
The milk production of camels in general was reviewed. Only in the USSR and in Saudi Arabia were any attempts made to milk camels by machine (Baimukanov, 1974). In the main the same milking methods are still in use as were probably used for the first domesticated camels. Milk is still shared with the calf (Photo 4) and many superstitions and ritual customs accompany the milking of camels. The dromedary gives more milk than the Bactrian. The milk yield of dromedaries does not vary so greatly between the various countries; the maximum daily milk yields are relatively large; and the lenght of lactation varies greatly, not only between countries, but also within a country. It is clear that status of feed and water will determine the amounts of milk for human consumption. Improving the feed is of prime importance in planning for better husbandry. Intensive farming will also allow for better husbandry and for easier implementation of selective breeding for high milk production. These aspects will be discussed in detail in other sections.
A most interesting phenomenon was discovered when research was carried out on intestinal lactase concentrations in various ethnic groups in Saudi Arabia (Cook & Al-Torki, 1975). Adult Arabs were found to have the highest lactase levels. This was supposed to demonstrate a selective advantage associated with the fluid and caloric value of camel milk and indicate the importance of camel milk for the survival of desert nomads.
Courtesy: FAO.orgNorth Kenya
In North Kenya the camels produce far more milk than the local cows. The Sakuye camel produces an average of 4 kg milk daily with a maximum of 12 kg. The cow produces 0.5–1.5 kg per day. Camels lactate for about a year. In areas with only one rainy season lactation finishes at the end of the dry season; this is thought to be caused by the shortage of feed during this period.
In areas of northern Kenya, where the nomads subsist almost entirely on camel milk, there are two rainy period. Field (1979a and 1979b) reported lactation studies lasting three lactations. The duration of lactation was 47–67 weeks. Lactation ended 4–8 weeks following conception. Daily milk production reached 21 kg in the first week, declining to 4.8 kg in the 16th week of lactation. There was an average daily milk yield of 13 kg for the first 10 weeks (1.8–50.2 kg) and 3 kg for the remainder of the lactation. Total production averaged 1 897 kg per animal. In the lactation studies the lowest milk yields were those given by camels without calves. These animals also had much shorter lactation periods, even though they were milked 5–7 times a day. Four milkings per day yielded more milk than twice a day milkings: seven liters compared with six (Evans and Powys, 1979; Shalash, 1979).
Ethiopia
The camel is known to be capable of producing large quantities of milk under extensive and intensive management (Knoess, 1979). Knoess rightly stresses the fact that as the camels are not intensively milked, but some milk is left for their calves, the exact amount is difficult to assess. Milk trials in the Awash Valley of Ethiopia were carried out for six days in various stages of lactation (Knoess, 1976). As suckling stimulus is an integral part of milk production (Yagil et al., 1975), it is obvious that in the short period of hand-milking the maximum milk producing capabilities were not fully exploited. Even so, eight liters in two milkings, or 2 470 kg over 305 days were obtained. The daily average for twice-a-day milking was estimated at 7 kg. These animals grazed on irrigated pastures. Under rainfed conditions, 13 kg per day can be milked (Knoess, 1979). It was found that some days the camels were milked 6–8 times a day, while other days they were not milked at all. This certainly would make the milk supply lower than if the animals were milked regularly each day. In the dry season the milk yield was about half that of the rainy season. This could be due to the lack of feed or to advanced stages of pregnancy (Lakosa, 1964).
Somalia
The lactation period is between 8–18 months (Mares, 1954a). The length of lactation depends on when the lactating dam is remated. The average daily yield in milk is 5 kg with a total yield of 1 950 kg. The amount of milk drunk by the calf is regulated by tying up one or more teats (Mares, 1954a). The amount the calf is allowed is determined by its needs and the milking capacity of the mother. Camels are milked twice a day; just after sunrise and at least two hours after sunset. Calves run with their mothers but are penned separately at night. From the age of six weeks they graze. When calves have finished suckling the amount left for consumption by the tent dwellers can vary from 1 to 4 kg (Epstein, 1970).
If a calf dies, the dam dries up if milking is not stimulated (Mares, 1954a). For this a foster calf or conditioning of the mother is necessary. Often arranging for the dam to see the skin of her dead calf is enough to stimulate let-down of milk. Fostering is done in three ways: (1) The foster calf is covered with the skin of the dead calf and allowed to suckle until the milk is flowing and the dam can be hand-milked. (2) The calf is tied down in front of the foster-mother, a rope being tied from the calf to the mother's muzzle. (3) The nostrils, ears or anus of the foster-mother are compressed with a special clamp. When the clamp is released, and the pain thus removed, the calf is presented for suckling. This is usually anough for the dam to allow the foster-calf to suckle.
In all cases the calf drinks from its own mother as well as from the foster-mother.
Algeria
The nomads of the Ahaggar in the Sahara depend on milk to given them a balanced diet (Gast et al., 1969). They have a saying “water is the soul; milk is life”, and hungry people say “I've lost the taste of milk”. Of course the camel is only one of the providers of milk. Goats, sheep and cows supply milk and milk products. The lactating camel produces 4–5 kg/day, on good pasture, for the first three months. A good milker can even provide up to 10 kg a day. When the udders are full the animals are milked three times a day, otherwise their swaying teats hinder their walking. After the third month of lactation the yield averages about 2 kg per day. The bad milkers dry off very quickly. It is therefore accepted that one camel is necessary to provide the requirements of one family. The camel herders' only source of food is camel milk.
The camels are tied down during the night and the camels' udders are covered with nets to prevent the young from suckling. The first milking takes place before dawn. The young calves are allowed to suckle for about one or two minutes. This is time for the milk to let-down. The calves are pulled away and the dam then milked for the tent dwellers. At twilight the camels are returned to the camp, and milked again after allowing the calves to suckle for a few minutes.
India
The geographical distribution of camels (dromedaries) in India, is in the States of Gujorat, Haryana, Maharashtra, Madhya, Pradesh, Punjab, Rajasthan and U.P. (Rao et al., 1970). The females calve for the first time at the age of 4 years. They lactate for 8–18 months. The amount of milk for the calf, and the amount that is milked, is regulated by tying up the teats to prevent the calf from suckling. The camels are milked twice a day. The daily milk production is between 2.5–6 kg, but often 15 kg per day is milked. Lactation yields range from 2 000 kg (Gohl, 1979) to 2 700–3 600 kg (Rao et al., 1970) under good feeding conditions, to about 1 360 kg, when feed supplies are poor (Yasin and Wahid, 1957).
Pakistan
The Arabian camel is found mainly in West Pakistan (Yasin & Wahid, 1957). Length of the lactation varies from 270–540 days; daily milk yields of 15 to 40 litres were recorded (Knoess, 1977). The total milk yield ranges from 1 350–3 600 kg. The lower milk yields were found in the areas where feed supplies are poor and under desert conditions. When the camels were well fed, there was an average milk yield of 10–15 kg per day (Yasin and Wahid, 1957). As much as 22 kg a day were obtained from some camels. In the areas with poor feeding the daily average was 4 kg. The heavy Pakistani camels produced up to 35 kg per day (Knoess, 1979). The desert camels gave more milk than the animals getting poor feed. These animals were milked twice daily.
Egypt
With good feeding a daily milk production of 10–15 kg was obtained (Shalash, 1979) giving a yield of approximately 3 000–4 000 kg per lactation. Daily yields of 22 kg have been recorded. Where feeding was precarious the daily production was only 4 kg, with a total production of 1 500 kg. These later data are similar to those presented by El-Bahay, 1962.
Israel
No actual recordings of milking have been made. Estimates of milk production range from 7 to 15 kg daily. Lactation periods vary from 9–18 months. In order to establish the total amount of milk produced by the lactating camel, the milk yield was measured indirectly (Yagil & Etzion, 1980). This method is based on firts marking the calves' blood with radioactive water. The calves were not allowed access to any drinking water as this would have made milk determinations impossible. The mothers were allowed drinking water only once a week for an hour, from the beginning of spring until the end of summer. The results show that there was a slight increase in milk yields as lactation progressed (5.7 to 6.2 kg). No decline was found when the animals were dehydrated. These data do not give the full potential of the camel as, in fact, what was measured was the calves' need for water. The calves ate the same feed as their mothers. They started eating within the first month of birth. Not withstanding this fact, it is quite clear that the feed demand of the calf is fairly large. In addition, research was carried out using the same diet throughout the year to eliminate nutritional factors affecting quantity and quality of milk. The natural grazing available to camels changes from winter to spring and in the summer the changes are even more drastic, in quantity and quality. With a decline in quantity the calves would tend to take more from their mothers than when the feeding is plentiful.
The milk production of camels in general was reviewed. Only in the USSR and in Saudi Arabia were any attempts made to milk camels by machine (Baimukanov, 1974). In the main the same milking methods are still in use as were probably used for the first domesticated camels. Milk is still shared with the calf (Photo 4) and many superstitions and ritual customs accompany the milking of camels. The dromedary gives more milk than the Bactrian. The milk yield of dromedaries does not vary so greatly between the various countries; the maximum daily milk yields are relatively large; and the lenght of lactation varies greatly, not only between countries, but also within a country. It is clear that status of feed and water will determine the amounts of milk for human consumption. Improving the feed is of prime importance in planning for better husbandry. Intensive farming will also allow for better husbandry and for easier implementation of selective breeding for high milk production. These aspects will be discussed in detail in other sections.
A most interesting phenomenon was discovered when research was carried out on intestinal lactase concentrations in various ethnic groups in Saudi Arabia (Cook & Al-Torki, 1975). Adult Arabs were found to have the highest lactase levels. This was supposed to demonstrate a selective advantage associated with the fluid and caloric value of camel milk and indicate the importance of camel milk for the survival of desert nomads.
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