A PROCESS FOR ISOLATING A BIOGAS PRODUCING MIXED CULTURE FROM ANIMAL EXCRETA,AND PRODUCING BIOGAS FROM NON-EDIBLE OILSEEDS OR CAKES USING SAID MIXED CULTURE

摘要

A process for isolating a biogas producing mixed culture from animal excreta, and producing biogas from non-edible oilseeds or cakes using said mixed culture, said process comprising:(i) fermenting a slurry of animal excreta such as herein described with water, hereinafter referred to as the first slurry, at ambient temperature and under anaerobic conditions with periodic dilution of said first slurry by periodically replacing said first slurry partly with a first nutrient medium consisting of mineral(s) such as herein described and cellulosic material(s) such as herein described and optionally vitamin(s) such as herein described until said animal excreta is completely removed by dilution to give a second slurry containing a first mixed culture degrading cellulosic material(s) such as herein described to biogas in the presence of mineral(s) such as herein described and optionally vitamin(s) such as herein described;(ii) further fermenting said second slurry containing said first mixed culture at ambient temperature and under anaerobic conditions in a second nutrient medium consisting of non-edible oil seeds or cakes such as herein described, cellulosic material(s) such as herein described and water with periodic dilution of said second slurry with said second nutrient medium by periodically replacing said second slurry partly with said second nutrient medium until mineral(s) such as herein described and vitamin(s) such as herein described, if any, in said second slurry is/are completely removed by dilution to give a third slurry containing a second mixed culture degrading a mixture of non-edible oilseeds or cakes such as herein described and cellulosic material(s) such as herein described to biogas;(iii) further fermenting said third slurry containing said second mixed culture at ambient temperature and under anaerobic conditions in a third nutrient medium consisting of non-edible oil seeds or cakes such as herein described and water with periodic dilution of said third slurry with said third nutrient medium by periodically replacing said third slurry partly with said third nutrient medium until said cellulosic material(s) is/are completely removed by dilution to give a forth slurry containing a final mixed culture degrading non-edible oil seeds or cakes such as herein described to biogas; and(iv) inoculating a fifth slurry containing non-edible oil seeds or cakes such as herein described in water, with said fourth slurry containing said final mixed culture and allowing said fifth slurry to ferment at room temperature and under anaerobic conditions to produce biogas said fifth slurry being periodically partly replaced by fresh supply thereof.