Biogas is a mixture of various combustible gas usually methane, carbon dioxide, water and hydrogen sulphides, which is produced by the breakdown of organic matter in the absence of oxygen. Biogas technology has the inbuilt potential to meet up the energy requirement needs of the present world.
It embarks efficient and judicious use of renewable resources, which is significantly capable of improving and securing the current energy generation scenario of any nation.
Need of Biogas
Since there is a limited amount of fossil fuel available to us and by the time it ends, we need to develop some alternative method of generating energy. Thus there is an emerging need for biogas production, due to several positive factors such as:
- Low operating cost of biogas power plant.
- Reduce greenhouse gas effect.
- Generation of energy with eco-friendly techniques.
Role of Anaerobic Digester in Biogas Production
Anaerobic digester plays a very crucial role in the production process of biogas. Basically digesting process incorporates a series of processes in which bacterial action decomposes biodegradable material in the absence of oxygen. The production of biogas requires environmental conditions which are suitable for the growth of methanogenic bacteria. To deliver optimum performance, the digestion process involves bacterial hydrolysis of the manure to break down insoluble organic polymers within a suitable temperature range.
In the anaerobic digester chemical reaction that takes place during production of biogas are:
- C6H12O6 → 2C2H5OH + 2C02
- 2C2H5OH + CO2 → CH4 + 2CH3COOH
- CH3COOH → CH4 + CO2
- C02 + 4H2→ CH4 + 2H2O
After proper decomposing action, the digester produces biogas mainly consisting of methane usually 80% by volume including other gasses which can be directly used as a fuel in combined heat and power gas engines.
As shown in figure it is clearly specified that the organic manure with the help of centrifugal pump is pumped to the anaerobic digester. After decomposing action biogas is produced, which is made to flow under high pressure through the combined heat and power gas engine. The gas engine is connected to an electrical generator by a mechanical drive arrangement to produce a balanced three phase electricity supply to the grid for the electrification purpose.
Energy is the basis of human life and one of the prime factor of nation’s economic growth. With the limited amount of fossil fuels present, generating energy from organic waste is really a matter of appreciation in the field of science and innovation. But there is a need for research and development organization to focus on newer and efficient low-cost design of biogas plant equipment for making it much more affordable and durable during installation process. Biogas has the power to revolutionize the energy production process quite efficiently, as it has a sustainable approach to fulfill the power demand of growing population.