Study On Carbon Resource Developing And Using Of Excess Activated Sludge From Municipal Wastewater Treatment Plant

Most municipal wastewater treatment plants had the crisis of carbon source shortage in our nation. Only use the biological method the nitrgon and phosphorus could not meet the discharge standard.As one of the most popularized technologies for wastewater treatment. Activated sludge technology prouduces a lot of by-product: excess activated sludge.The percentage of the cost of excess activated sludge dispose becomes bigger in the running costs of wasterwater treatment plants.This research focus on the two problems; the wastewater treatment plants water had low carbon resources and the excess activated sludge dispose. Study the excess activated sludge product volatile fatty acids (VFAs) by the alkali pretreatment at the anaerobic condition.The experimental demonstrate that the stirring rate was 60-80rpm,the reaction time 4d,the initial pH was 10,the total solids was 88 g/L were the best conditions for excess activated sludge product VFAs.At this conditions can realize the best result of reaction time and the quantity of acidizing by centrifugal separation.Based on the last stage, at the semi-contimuty condition control the best operation parameters. Reaserch three situations:non-filler, spheric shape fillings, combined packing. The result showed that, the VFAs production at nearly 4991 mg/L,5984 mg/L,6879mg/L.Combined packing to effectively improve the production of VFAs.Acidizing fluids not only contained VFAs, but also contained SS,N and P.In this paper, pretreatment of acidizing fluids to remove the SS by centrifugation, N and P recovery as guano. The removal rate can amount of 85.2%,72.6%,83.8%.Test results show that dosing the pretreatment acidizing fluids can effectively improve the biological nitrogen phosphorus removal efficiency. Dosing the greater the denitrifying reaction more thoroughly, denitrifying rate faster. Acidizing fluid dosing quantity for 30mg/L,biological nitrogen phosphorus effect than other three groups of testing is best. Three groups of testing anaerobic conditions nitrogen the removal rate of 56%, 73.2%,81.4%,95.8%;and Aerobic conditions SP removal rate of 26.6%,46.6%,69.2%, 93.0%.This topic try to solve the problems of carbon source insufficient due to N and P removal ineffect and the excess activated sludge dispose.Realization utilization of excess activated sludge,in line with our philosophy of environmental protection energy saving.Provide reference for the construction and run of waste wastewater treatment plants.