05-01-2015, 10:03 PM
1. Biogas usually contains about 55-65% methane, 30-35% carbon dioxide, and some hydrogen, nitrogen and other impurities. Its heating value is around 600 BTU per cubic foot (21 BTU per litre).
2. Natural gas contains about 80% methane, with a heating value of around 1000 BTU per cubic foot (35 BTU per litre).
3. Filtering biogas, or "scrubbing" it, can remove the carbon dioxide and the other impurities, raising the BTU.
4. There are two basic types of digester, batch digesters and continuous digesters. Batch digesters are filled with a mixture of organic wastes and water (slurry) and sealed, and emptied again when they stop producing gas. Continuous-load digesters are fed a daily load of slurry, with gas and digestion wastes produced continuously.
5. Biogas digestion works best at 25 to 35 deg C, 77-95 deg F.
6. One pound (0.45 kg) of cow manure can produce about one cubic foot of gas (28 litres) at around 28 deg C (82 deg F) — enough to cook a day's meals for 4-6 people in India.
7. About 1.7 cubic metres of biogas (60 cubic feet) equals one litre of gasoline (1/4 gallon). The manure produced by one cow in one year can produce enough methane to replace more than 200 litres of gasoline (53 gallons).
Image source: https://www.pinterest.co.uk/explore/anae...digestion/
2. Natural gas contains about 80% methane, with a heating value of around 1000 BTU per cubic foot (35 BTU per litre).
3. Filtering biogas, or "scrubbing" it, can remove the carbon dioxide and the other impurities, raising the BTU.
4. There are two basic types of digester, batch digesters and continuous digesters. Batch digesters are filled with a mixture of organic wastes and water (slurry) and sealed, and emptied again when they stop producing gas. Continuous-load digesters are fed a daily load of slurry, with gas and digestion wastes produced continuously.
5. Biogas digestion works best at 25 to 35 deg C, 77-95 deg F.
6. One pound (0.45 kg) of cow manure can produce about one cubic foot of gas (28 litres) at around 28 deg C (82 deg F) — enough to cook a day's meals for 4-6 people in India.
7. About 1.7 cubic metres of biogas (60 cubic feet) equals one litre of gasoline (1/4 gallon). The manure produced by one cow in one year can produce enough methane to replace more than 200 litres of gasoline (53 gallons).
Image source: https://www.pinterest.co.uk/explore/anae...digestion/
