Anaerobic Digestion in Bio Mass and Steps Involved in The process Of Anaerobic Digestion

Anaerobic Digestion is a series of biological process in which micro-organisms break down biodegradable materials in the absence of oxygen. One of the end product is bio-gas. Anaerobic digestion is used to convert live stock manure. municipal waste water solids, food waste, high strength industrial waste water and residuals, fats, oils and greases into bio-gas.

Various steps Involved in Anaerobic Digestion

Anaerobic Digestion involves the following four stages of biological and chemical reactions.

Stage 1 : Hydrolysis

The digestion process begins with bacterial hydrolysis of the input materials to break down insoluble organic polymers to soluble materials such as carbohydrates and make them available for other bacteria.

Stage 2 : Acidogenesis

Then , acidogenic bacteria converts the sugars and amino acids into carbon dioxide, hydrogen, ammonia and organic acids.

Stage 3 : Acidogenesis

These organic acids are converted into acetic acid along with additional ammonia, hydrogen and carbon dioxide by the acetogenic bacteria acetic (acid-forming bacteria) .

Stage 4: Methanogenesis

Finally, The above products are converted into methane and carbon dioxide by methanogenesis (methane - forming bacteria . Thus, the final chemical reaction for the overall processes

C6H12O6----------> 3CH4 + 3CO2

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Mechinopedia For Mechanical Engineers

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