Producing Bio-gas from kitchen waste

In Alagappa University, kitchen waste is used to generate thermal energy for cooking and heating. The bio-gas produced from food waste, decomposable organic material and kitchen waste, consisting of methane and a little amount of carbon dioxide is an alternative fuel for cooking gas (LPG). Kitchen waste is mechanically processed and moistened to produce a suspension that subsequently undergoes a fermentation process. Fermentation produces biogas – a valuable energy source – that is desulphurised by biological means. Also, the waste materials can be disposed off efficiently without any odour or flies and the digested slurry from the bio-gas unit can be used as organic manure in the garden. The major components of the bio-gas plant are a digester tank, an inlet for feeding the kitchen waste, gas holder tank, an outlet for the digested slurry and the gas delivery system for taking out and utilizing the produced gas.

Eco-friendly technology allows for the production of renewable natural gas in the form of biomethane. The facility processes about 100 tons of kitchen waste every year – mainly the contents of organic waste from University Hostels, as well as leftover food from university canteens and expired food.

This project is also useful for students to have a hands-on learning experience in constructing a Mini Bio-Gas Plant, using locally available material. The biogas is installed and maintained by the Department of Energy Science, Alagappa University.