Study on the variation of microorganism in dewatered sludge fermentation by alternative method

The dewatered sludge was fermentation treated in barrel fermentation device to produce garden nutritive soil,the variation of fermentation temperature,colony numbers of bacteria,actinomycetes and fungi under different fermentation process was studied.Results showed that high temperature stage(50 ℃) of all fermentation process was longer in summer than in winter.The aerobic-anaerobic alternating fermentation in summer duration longer period of temperature above 55 ℃ than the aerobic fermentation.After aerobic and alternating fermentation process,the number of coliforms in composting could meet the harmless requirement of "urban sewage sludge disposal for landscape utilization"(CJ 248-2007).In the summer aerobic-anaerobic alternating fermentation process,the fermentation temperature was decreased after anaerobic process and then returned after aerobic process.The bacteria was dominated biotype both in aerobic and alternating fermentation process,the number of actinomycetes and fungi was lower than that of bacteria by 2-6 orders of magnitude.