Development And Application Of Microbial Agent In The Fast,Nitrogen Conservation And Deodorizing Compost Of Municipal Sludge

Sludge compost can realize the requirements of urban sludge treatment and disposal,such as resource utilization,innocuity and reduction.The fertilizer produced can be used in landscaping and agricultural production,however,the long fermentation period,the serious odor and the large amount of nitrogen loss in sludge composting limit the application and popularization of sludge composting technology.In order to improve the fermentation effect of sludge compost,this paper mainly studies the effect of bioaugmentation aerobic composting on temperature rise,nitrogen conservation and deodorization.This paper is divided into the following four parts:（1）Screen out the dominant microbial strains from the sludge for the bioaugmentation of the sludge compost.（2）Study the nitrogen conservation and deodorization effect of the sludge compost strengthened by phosphoric acid buffer.（3）Under the optimized composting conditions,the nitrogen retention and deodorization effects of bio-enhanced mixed bio-carbon compost were studied.（4）Under the optimized composting conditions,the effects of bioaugmentation mixed phosphoric acid buffer on nitrogen retention,deodorization and rapid heating of sludge compost were studied.The main conclusions are as follows:（1）Two kinds of bacteria were screened and used in bioaugmentation composting.The two kinds of bacteria were identified as enterobacter aerogenes and Klebsiella pneumoniae through physiological and biochemical identification.The optimum growth conditions for the mixed culture of the two strains are as flollows:the optimum temperature is 50℃,the optimum p H is 7.5,the optimum carbon dosage is 1.0%（m/V）,and the optimum nitrogen dosage is 1.5%（m/V）.（2）The decomposition and transformation of TB-polysaccharide and TB-protein were significantly improved by phosphoric acid buffer,and the total nitrogen of sludge compost increased by 20.16%and NH₃ release decreased by 37.465 compared with the blank compost.（3）The fermentation time of bioaugmentation-biochar was 2 days longer than that of blank compost（>55°C）,and the degradation rate of organic matter was increased by 11.26%.The total nitrogen of bioaugmentation-biochar was increased by 20.35%compared with blank compost.The accumulation of NH₃ and H₂S decreased by 55.40%and 70.84%,respectively,compared with blank compost.And the biochar-added compost had higher Firmicutes activity.The bioaugmentation-biochar had strong activity of Proteobacteria,Bacteroidetes,Actinobacteria and Firmicutes,and it could improve the bioactivity and tolerance of microorganisms in the bioaugmentation-biochar.（4）The temperature of bioaugmentation-phosphoric acid buffer was higher than that of the blank compost,and the degradation rate of organic matter was increased by 7.37%,and the total nitrogen of bioaugmentation-phosphoric acid buffer was increased by 10.46%compared with blank compost and The accumulation of NH₃ and H₂S decreased by 38.10%and 62.23%,respectively.The bioaugmentation-phosphoric acid buffer significantly changed the relative abundance of OTU and bacteroidetes in the high temperature period,which was helpful to enhance composting and maturity.