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Sewage sludge contains a wealth of N , P, K , and a variety of trace elements , also contain refractory organics , heavy metals and pathogens and other harmful substances , disposal properly, will not only cause serious pollution to the environment , but it is also the resource waste. Conventional landfill, incineration and disposal methods are not suitable for China because there is the disadvantage of high cost and environmental pollution . This paper focuses on the feasibility of the use of Municipal Sewage Sludge Preparation fertilizer . According to a certain proportion to the pressure filtration sludge , adding bulking agents and conditioning agents (mainly ash , sawdust and compostable products ) , to adjust the moisture content , the volatiles and C / N ratio and other parameters ; Then, the mixed material through a fermentation ( fermentation period of 10 days ) , and the secondary fermentation ( fermentation period of about 20 days ) after the indicators in line with national standards can be prepared compost product ; Finally, in accordance with the mass ratio of compost products : urea : superphosphate : chloride the proportion potassium = 1:0.31:0.28:0.15 to add inorganic fertilizers , compost quality inorganic - organic compound fertilizer .
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