Biodegradable waste is a type of waste, typically originating from plant or animal sources, which can be decomposed by other living organisms. Biomass, manure, sewage, municipal waste, green waste and plant materials are some of these common biodegradable waste. ANAEROBIC DIGESTION:
This is a series of biological processes in which microorganisms breakdown biodegradable materials in the absence of oxygen. One of the end products is biogas which is combusted to generate electricity and heat or can be processed into renewable natural gas and transportation fuels. THE BIOLOGICAL PROCESS:
The digestion process begins with bacterial hydrolysis of the input materials in order to breakdown insoluble organic polymers such as carbohydrates and make them available for other bacteria. Acidogenic bacteria then convert the sugars and amino acids into carbon dioxide, hydrogen, ammonia and organic acids. Acetogenic bacteria then convert those resulting organic acids into acetic acid, along with additional ammonia, hydrogen, carbon dioxide. Finally methanogens convert these products to methane and carbon dioxide. ANAEROBIC DIGESTION AND METHANE GAS CAPTURE:
As materials decompose or ferment, certain gases are emitted. Methane is a gas that is created during the decomposition process. Methane can be captured and use to produce energy by burning the gas in many different ways. However, the gas is typically captured by funnels or covers that encase city landfills or sewage and lagoon systems.
Many different anaerobic systems are commercially available. The following is an overview based on organic waste stream type. MANURE: Anaerobic digestion system for livestock manure operate to reduce Methane emissions, odors, pathogens and weed seeds and produce biogas. They fall into four general categories •Covered anaerobic lagoon digestion