All About Anaerobic Digestion
At Mailhem, we consider it our responsibility to promote waste to energy plants and reduce the amount of waste in India. We constantly promote and support sustainable use of resources. Our ability to deliver anaerobic digestion solutions helps in reducing the waste and producing fuel.
What is Anaerobic Digestion?
In anaerobic digestion, there is a sequence of processes in which microorganisms break down various biodegradable materials (waste collected) in the absence of oxygen. It is an extremely useful process in commercial, industrial and domestic applications.
In the anaerobic digester, there is physical containment of the sealed tanks to prevent oxygen from entering the system. Anaerobes access oxygen from sources apart from the surrounding air. It could be the organic material itself or supplied through the input material in the form of inorganic oxides.
Anaerobic digestion needs a steady form and type of organic matter or waste —it could be animal litter, food waste, industrial organic waste, slaughterhouse waste, corn silage (energy crop), fresh produce wastes, crop residue from harvesting or processing, and sewage. It is then held in a controlled environment to create biogas and residue. While the biogas can be used for certain purposes without further processing, it may be processed to remove the carbon dioxide and hydrogen sulphide along with water vapour.
Benefits of Anaerobic Digestion:
Anaerobic digestion generates electricity or Compressed Biogas (CBG) from Biogas.
The Government of India’s initiative has made biogas plants exempt from excise duty and eligible under Corporate Social Responsibility and 80% depreciation is admissible. Mailhem’s Anaerobic Digestor is based on the Modified Upflow Anaerobic Sludge-Blanket (M-USAB) technology. It offers efficient management of waste and results in stabilized bio-manure. Successful use of biogas technology can also provide other benefits like the production of bio-fertilizer, social and ecological benefits including, sanitation, reforestation and reducing the reliance on fossil fuels.
The system generates three by products — Biogas, Bio-Manure & Liquid Digestate Overflow.
The digestate liquid overflow from anaerobic digester is partly recycled to save up to 75% of fresh water. The digestate bio-manure is periodically taken out from bottom of anaerobic digester and can be used in multiple applications. Neat and hygienic disposal of organic waste is done at its source of generation and hence, there’s no nuisance of waste transport on public roads. Only a small footprint area is required due to tank-in-tank digester and it can be tailor-made to suit your site requirements. Using anaerobic digesters helps in reduction of Green House Gas (GHG) emissions
The Semi-automatic operation ensures easy maintenance and less wear and tear of equipment. Depreciation is available on the biogas plant for profit making companies.
Process of Anaerobic Digestion
The segregated organic waste at plant is crushed into smaller size using crusher along with suitable quantity of fresh or recycled water to form slurry, collected in the inlet chamber.
The slurry from the inlet chamber is then fed to the anaerobic digester, which has internal baffles, partitions and launders (proprietary) for anaerobic treatment. In the anaerobic digester, the segregated organic MSW is converted to biogas, bio-manure and digestate liquid overflow. The biogas generated from the anaerobic digester is collected in membrane (balloon) type biogas holder. The same is further suitably scrubbed for h2s and then fed to 100% biogas engine for power generation.
Part of the digestate liquid overflow is recycled for slurry preparation to save on fresh water use. Balance liquid overflow can be utilized as liquid manure after suitable dilution or connected to existing STP / ETP. The digestate bio-manure is removed periodically from the bottom of the digester and is used as good soil enricher. Excess biogas if not used is flared and not vented out to the atmosphere, keeping the environment clean and green.
At Mailhem, we can help you set up your waste management plant based on your requirements and assist you throughout the lifecycle of the anaerobic digesters.
Call us today +91 93735 97455 if you’d like to know more about anaerobic digestion.