Special Uses Biogas
Biogas is an important renewable energy resource for rural areas. Generation of bio-gas from dung and urine is a very simple and cost-effective way of producing energy for lighting as well as cooking. Biogas can be used to operate a dual fuel engine to replace up to 80% of diesel-oil. Diesel engines have been modified to run 100 % on biogas. Production of bio-gas also results in the production of a very useful by-product in the form of slurry, which is an extremely good manurial source, and it contains more nutrients than that in compost.
a. Vermicompost
b. Natural Composting helps in converting some organic solids in to carbon dioxide, thus, reducing volume. Natural composting takes at least 6 months to get the desirable effect. However, length of composting time can be reduced to 60-75 days by addition of earthworms @ 1 kg/10 quintal of dung in trench method. Vermi-composting helps not only in reducing the quantity but also helps in increasing the N,P,K content to 3 to 4 times more than that of farm yard manure
Table- NPK Content (%) in various types of manures
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Types of manure
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Nitrogen (N)
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Phosphorus(P)
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Potash (K)
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Farmyard manure /compost/slurry
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0.5
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0.5
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0.25
|
|
Vermicompost
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1.5
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2.0
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1.0
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Biofertilizer
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3.0
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1.0
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1.0
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which about 0.5, 0.5 and 0.25 percent of Nitrogen, Phosphorous and Potash; respectively. So in Vermicompost the N,P,K increase 3 to 4 times as compared to ordinary compost (Table 3). Addition of algae (Azolla) and some other nitrogen and phosphorus fixing bacteria may further increase the manurial value of vermin compost.
c. Bio-dynamic fertilizer
1. Fresh cow dung is collected in the hollow of cow's horn and kept in the dung heap for 6 months. It is said that 35 gram manure prepared by this methods mixed in 10 lit of fresh water is sufficient for 1 acre of land. This may help in development of favourable microbes due to anaerobic fermentation, which can kill the pathogen in the field. This however, is not a proven technology.
d. Panchgavya
The phrase gavya is given to cow's products. Panchagavya comprises cow dung, cow urine, cow's milk, curd and ghee, suitably mixed to give beneficial growth effects on plants when sprayed on them.