This document discusses biogas production through anaerobic digestion. It begins by defining biogas as a mixture of methane, carbon dioxide, and other gases. It then discusses common substrates used for biogas production, including animal and agricultural waste. The document outlines the four phases of anaerobic digestion - hydrolysis, acidogenesis, acetogenesis, and methanogenesis - through which microorganisms break down organic matter to produce methane and other gases. It also provides details on the anaerobic digester process, temperature and pH requirements, and factors that stimulate biogas production. China and India are highlighted as countries with large numbers of biogas plants, especially in rural areas.

1. Biogas Production

2. Content
 Introduction
 Biogas Production
 Substrates for Biogas production
 Phases in production of Biogas
 Processes and limitations

3. Introduction
 Biogas is a mixture– Methane (50-80 %), CO2 (15-
40 %), Nitrogen (5%) and Hydrogen sulphide (1%)
 Common Names- Gobar, Sewage, Klar and
Sludge gas.
 It is Gaseous Fuel and serves as a good source
of energy.
 Cooking
 Produce Electricity
 Methane- Fuel used for domestic and Industrial

4. Biogas production
 This gas is significantly contributes to World’s
energy source
 China is largest number of biogas- 7 million units
 Recently- Indian government Encouraged 25%
subsidy, Bank Loan. It is very popular at rural areas.
 Pakistan also has good numbers of biogas plant.

5. Substrates for biogas
 Common – Waste Products of Animal Husbandry, waste
from house, Industry, Municipal and Agricultural.
 In India- Cattle Dung (Gobar), in China- Pig Dung
 The concentration of organic dry matters/ Total solids
(TS)
Low Grade(<1%), Medium (1-5%), High (20-40% TS), Solid
(20-40 %). High Grade waste are preferred for biogas
production.
 Eichornia crasipes Aquatic weed good source of
production of Methane
 Azolla also is equally important source for production of
Methane

6. Phase 1
• Hydrolytic Phase
• Organic matter into Complex organic materials
Phase 2
• Acidifying Phase
• Formation of Organic acids, H2 and CO2
Phase 3
• Acetogenic Phase
• Acetogenic bacteria converts alcohol into acetate
• Also it is generate acetate from H2 and CO2
Phase 4
• Methanogeneic Phase
• Methanobacterium omelianskii, Methanobacterium
formicicum
Microbial Production of Methane-
Methanogenesis

7. Low
molecular
soluble
products and
organic acids
Cellulose
Starch Proteins
Lipids
Organic
acids
H2 CO2
Alcohol
Acetate
Methane

8. Process of biogas production
 Anaerobic digester
 Cow dung
 Methanogenic bacteria
 Entire digestion process 2-3 weeks
 Used slurry- Manure
 Temperature- 30-40° C
 pH- 6-8
 Ration of water and slurry 1:1 ratio
 C:N ration 30:1
 Should be Anaerobic condition
 Ammonium Sulphate and Antibiotics stimulate factor
 Also Agri waste, pig and chicken wastes, paper
waste contain rich sulfate

9. Reference
 Sathyanarayan (2018) Biotechnology. Books and
Allied publishers Kolkata.

10.  Thank you
For any Clarification Contact;
Dr. T. RAMESH
Assistant Professor of Zoology
PG & Research Department of Zoology
Vivekananda College Tiruvedakam
+91 99420 58831
faunaldiversity@gmail.com