Anaerobic digestion is the biodegradation of the organic waste with the aid of bacteria which performs it work in the absence of oxygen. The main objective of anaerobic digestion is the degradation and destruction of organic substances, with consequent reduction of the pathogens. & odorous emissions. Anaerobic digestion process consists of four major steps: hydrolysis, acidogenesis, acetogenesis an methanogenesis vegetable wastes are a fine substrate with possibility to produce methane and are available. In abundance This work reviews the various parameters affecting the biodigestion process. A careful consideration when selecting the working method parameter such, organic loading rate (OLR), C/N ratio, Gas production rate inoculums to substrate ration (ISR) temperature & pressure hydraulic retention time, Electricity generation calculations are given. Improvement in C/N ratio, higher bio-degradability, effective volatile solids (VS) elimination, ecofriendly sludge production has been regarded as advantage of co-digestion process.

Bio-digesters convert organic waste (agricultural and food waste, animal or human manure, and other organic waste), into energy (in the form of biogas or electricity). An added benefit to bio-digestion is a leftover high-grade organic fertilizer. Models of the Bio digestion process do exist, but either relies on simple algebraic equations instead of biochemical reactions, or considers so many external parameters that they become overly complicated and require much input information and computation time. This work provides the review of features and limitations of different kinetic models of bio digestion process to enhancement on productivity.