| Urban sewage sludge is one of the most renewable resources in solid waste. Land utilization after urban sewage sludge composting is considered one of most potential methods. However, a large number of ligin and cellulose in the traditional compost contribute to composting period very long and lack of effectiveness. Moreover, there is a great deal of nitrogen loss during the composting, which not only lead to environmental pollution but also decrease the economic value of urban sewage sludge land utilization. So, how to reduce the period of sewage sludge compost, accelerate fermentation speed and increase the nutrient content in sewage sludge are very important to the utilization of land . The aerated static pile composting system and artificial inoculation white rot fungus were conducted in this study, in order to reduce the maturity time, improve the sewage sluduge treatment efficiency, and we also studied the optimal inoculum concentration and the changes of nutrients during the sewage sluduge compostings. The main results were as follows:1. Three kinds of natural wastes rice straw, wheat bran sawdust as well as sewage sluduge were used as major raw material, with different material combination as A (sewage sludge + rice straw + sawdust + wheat bran(12: 2: 1: 1.5)); B (sewage sludge + sawdust + wheat bran(12: 3: 1.5)); C (sewage sludge + rice straw + wheat bran(12: 3: 1.5)) , which were carried out a composting simulated indoor study in 48 days, white rot fungus according to different proportion as 0%,1%,2%,5%(v/m) were inoculated in different material combinations sewage sludge composting at the 8th day. The study showed that white rot fungus which was inoculated to different sewage sludge material combinations could prolong 1 to 3 days high temperature time in sewage sluduge composting and increased xylanase activity and cellulose activity in the composting, which accelerate xylanase, cellulose and other organic compounds decomposition in the composting, but had no effect to the pH and the whole quantity of the microorganism.2. A material combination piles which inoculated 2%, 5%white rot fungus turned to maturity in 20 days after composting and advanced 8 days to the pile which without white rot fungus. B material combination piles with different proportion white rot fungus reached maturity in 20 days after composting and were ahead of 4 days to the control. However, C material combination pils which inoculated 2%, 5% white rot fungus reached maturity in 28 days after composting and shortend 8 days comparing with the control.3. After 48 days composting, total nitrogen contents in A piles which inoculated different proportion of white rot fungus decreased 30.10, 22.60, 21.80, 25.90% respectively compared with the initial compost, while total nitrogen contents in B piles decreased 23.90, 15.30, 22.30, 20.90% respectively, and in C piles declined 39.80,39.00,33.90,38.00%. At the end of study, the nitrate nitrogen content of A piles was 1469.5, 1519.19, 1677.59, 1588.95mg/kg respectively, in four treatment; in B piles the content of NO3-N was 1656.13, 1722.67, 1679.57, 1700.93 mg/kg respectively; while in C piles arrived 489.27 , 508.67, 713.63 , 598.62 mg/kg , respectivel. This study showed that inoculation of white rot funfuge is benefical to reduce nitrogen loss during the sewage sludge compost. The content of total P,K and the available P, K content in different material combination and different treatments had a tendency of increase because of the effect of concentrated, Inoculation of white rot funfuge also had a certain extent significant effect on the total P,K content and the available P, K content.4. Taking the asseccmeny of ferment time and nutrient indicators during the compost into account comorehensively, we found that A piles with 2% white rot funfuge, B piles with 1 % white rot funfuge and C piles with 2% white rot funfuge had good effects on accelerating compos, reducing the loss of nitrogen and increasingnutrient content.
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