Bio gas principle of production

Bio gas, its principle and production all you need to know.

1. BIO GAS PRP PRINCIPLE OF PRODUCTION

2. BIOCHEMICAL CONVERSION By the use of metabolic action of microbial organism on biomass to produce liquid and gaseous fuels. There are two types…. Fermentation process, Anaerobic digestion.

3. ANEAROBIC DIGESTION An anaerobic is a micro organism that can live and grow without air or oxygen, it gets oxygen by the decomposition of matter containing it. It involves wet biomass & animal waste into biogas through decomposition process by the action of anaerobic bacteria. The biogas production depends on, The type of biomass used, Temperature, PH value of mixture etc.

4. Gas produced by the anaerobic digestion or fermentation of organic matter under anaerobic conditions. Typical biogas composition: Methane, CH 4 : 55-65% Carbon dioxide, CO 2 : 30-40% Nitrogen, N 2 : 1 % Hydrogen Sulphide , H 2 S : 0.1 % Hydrogen, H 2 : 1-2 % Oxygen, O 2 : 0.1 % pH-value : 6.5 to 7.5 What is biogas?

5. PRINCIPLE OF BIOGAS PRODUCTION The production of biogas is achieved by the action of anaerobic bacteria in the presence of moisture & in the absence of oxygen. The conversion process is called bio digestion. The bio chemical process take place in three stages. Enzymatic hydrolysis Acid formation Methane formation

6. ENZYMATIC HYDROLYSIS Complex compound such as fat, protein, carbohydrates are broken into simple water soluble organic compounds through the influence of water called hydrolysis.

7. ACID FORMATION Acid forming bacteria produced mainly acetic acid & Propionic acid at low temperature and release of co 2. Duration of 2 week and during this process large amount of co 2 is given off.

8. METHANE FORMATION Anaerobic bacteria called as methane formers converts organic acid into biogas having main constituents as methane & carbon dioxide with other small traces of hydrogen and nitrogen etc… These methane former bacteria are sensitive to PH changes. PH value in between 6.5 to 8 is the best for the fermentation

9. COMPLEX ORGANIC MATTER SIMPLE ORGANICS ACETATE H 2 / CO 2 METHANE and CARBON DIOXIDE LOW ODOR EFFLUENT LIQUEFACTION PHASE GASIFICATION PHASE ACIDOGENS METHANOGENS

10. FACTORS AFFECTING THE PRODUCTION OF BIOGAS Temperature (Pshchrophilic-10-20, Mesophilic-35-38, - Thermophilic40-45 degree centigrade. Gas stops if temp go beyond 10 degree) Pressure (2-200 psi) Solid concentration & HRT(8-10%,30,40,55 Days), Retention period (30-45 days), Winter-60 Days PH value(6-7) Nutrients composition ( Straw are added to increase the N content) Uniform feeding Diameter to depth ratio(16 feet depth & 4 to 5 m diameter)( 0.66-1.0) Carbon to nitrogen ratio(30:1) Toxicity due end product- should b harmful to bacteria Stirring or agitation of the content of digester Loading Rate- Should be kept const

11. BIOGAS PLANT A STRUCTURE INSIDE WHICH ANAEROBIC DIGESTION OF ORGANIC MATTER TAKES PLACE AND BIOGAS IS PRODUCED

12. Components of biogas plant Inlet pipe : The slurry is moved into the digester through the inlet pipe/tank. Mixing tank : The feed material like dung is gathered in the mixing tank. Using sufficient water, the material is thoroughly mixed till a homogeneous slurry is formed. Digester: Inside the digester, the slurry is fermented. Biogas is produced through bacterial action. Gas holder or gas storage dome : The biogas thus formed gets collected in the gas holder. It holds the gas till the time it is transported for consumption. Outlet pipe: The slurry is discharged into the outlet tank. This is done through the outlet pipe or the opening in the digester. Gas Pipeline: The gas pipeline carries the gas to the utilization point like a stove or lamp

13. One m 3 of biogas is equivalent to 0.7 m 3 of natural gas, 0.7 kg of fuel oil, 0.6 kg of kerosene, 0.4 kg of benzene, 3.5 kg of firewood, 12 kg of manure 4 kWh of electric energy, 1.5 kg of coal, 0.433 kg of LPG 1.6 kg of CO 2

14. Biogas consumption for different applications Use Specification Quantity of gas consumed (m 3 /hr) Cooking 2" burner 0.33 4" burner 0.47 6" burner 0.64 per person per day 0.24 m 3 /day Gas lighting mantle lamp of 100 Candle Power 0.13 Duel fuel engine 75-80% replacement of diesel oil per B.H.P. 0.50 Electricity 1 kWh 0.21