Abstract

                                Comparative evaluation of biodigestion of wastes viz. Saranai, nutgrass, subabul leaves, rain tree leaves after mixing with coudung and swine manure to obtain a C:N ratio of 20:1 and 30:1 in relation to biogas output and microbiological activities were carried out. Maximum destruction of total solids (TS) and volatile solids occurred in treatment containing suine manure, coudung and saranai mixed to arrive to final C:N ratio of 27:1, which recorded the highest gas output of 79.4 litres over twelve weeks period. Maximum methanogenic population of 128.5 x 104/g was also observed in the same treatment. A judicious combination of wastes to arrive at a C:N ratio between 27:1 and 30:1 seems to be the optimum mix for enhancing gas yield.

Key words : Wastes, Biodigestion, C:N ratio, Microbe, Biogas.