Research on the Application of Compound Microbial Agent in Aerobic Composting of Sludge and Straw
Aerobic composting is one of the most potential disposal methods realizing sludge reduction, innocuity and resource utilization simultaneously. To strengthen the aerobic composting process of sludge and improve composting quality, compound bacterial agent were formed by mixing Azotobacter chroococcum,Bacillus cereus and Bacillus amyloliquefaciens with the equal ratio. The sludge was mixed with corn straw according to the volume ratio of 1:1.5, the moisture content of the mixture was adjusted to 60％ by drying, then the mixture was inoculated with 10％ compound microbial agent and put into the composting device, and the air flow is adjusted to 0.20 L/min for aeration fermentation for 15 d, the TN, TC, TP and TK of the sludge composting were (23.20±0.21) g/kg, (230.80±0.56) g/kg, (3.13±0.03) g/kg and (1.55±0.01) g/kg, respectively, the germination index was (129.95±5.42)％. Compared with the control group, the contents of nutrient substrate were increased, and the contents of heavy metals were decreased significantly, except As, other heavy metal indexes were lower than the limits of national standard of organic fertilizer. The decrease of total nitrogen, the increase of total phosphorus and the decrease of heavy metals in the compost of the compound microbial agent fermentation indicated that the compound microbial agent had the functions of nitrogen fixation, phosphorus accumulation and passivation of heavy metals, this will help to solve the problems of low composting efficiency, high nutrient loss and excessive heavy metals in municipal sludge composting.
Municipal sludgeSludge compostStrawCompound microbial agent
万方数据
维普
