Interactive effects of temperature and o-cresol co-disposal on the methanogenic fermentation of refuse

The influence of temperature on both o-cresol biodegradation and methanogenic refuse decomposition was investigated. Maximum o-cresol attenuation was recorded from 25 to 37 degrees C. Mesophilic and thermophilic sulphate-reducing bacterial (SRB) activity was observed, but thermophilic methanogenesis was not recorded. Maximum methane release and SRB activity was recorded at 25-37 degrees C, and greater than or equal to 30 degrees C, respectively. Optimum conditions for acetate utilization were similar to those for methanogenesis, but propionate degradation apparently depended on SRB activity. Propionate degradation was recorded under thermophilic conditions, even in the absence of methanogenesis, although the optimum temperature was 37 degrees C. When SRB were inhibited, at temperatures less than or equal to 25 degrees C, no significant propionate catabolism was observed.