基于臭氧旁路处理的污泥原位减量技术工艺

探究基于臭氧旁路处理的污泥原位减量技术在不同臭氧含量以及不同污泥龄条件下的工艺参数和污泥性质.本研究发现75 mg·g^-1（以O₃/MLVSS计）为实现污泥减量并维持污水处理系统正常处理能力较为适宜的臭氧含量，该含量下的臭氧旁路处理后污泥产率系数Y_h从0.331 g·g^-1减少到0.326 g·g^-1，衰减系数K_d从0.046 d^-1增加到0.050 d^-1，污泥产生速率减小，衰减速率增大，且污泥龄为10 d时SBR系统出水水质良好.即臭氧含量75 mg·g^-1、污泥龄为10 d条件下的臭氧旁路处理为适宜的工艺条件，此时剩余污泥减量12%.该工艺条件下的臭氧旁路处理改变了剩余污泥中微生物在门和属上的种群丰度，臭氧旁路处理后拟杆菌门相对丰度增加1.2倍，与硝化和反硝化相关的变形菌门相对丰度从24%降低到18%，硝化细菌相对丰度的减少影响了污水处理系统的脱氮能力，但出水总氮仍满足一级B排放标准；在属上Lactococcus等乳酸菌的种群相对丰度从0.4%增加到21.6%.同时，剩余污泥胞外聚合物（EPS）中蛋白质与腐殖质类等大分子有机物比例增加，使CST值从15 s升高至17 s，Zeta电位从-10.04 mV下降至-15.20 mV，剩余污泥的SVI由54 mL·g^-1升高至62 mL·g^-1，说明沉降性能和脱水性能受到一定影响，但系统的出水SS含量以及抽滤后泥饼含固率变化不明显，系统仍能够稳定运行，未明显影响剩余污泥的后续脱水.

In-situ Sludge Reduction Technology Based on Ozonation

The process parameters and sludge properties of an in-situ sludge ozone-reduction system were investigated under different ozone dosages and sludge ages. Subsequently, 75 mg·g^-1 (as O₃/MLVSS) was selected as the appropriate ozone dosage to satisfy the wastewater treatment capacity and in-situ sludge ozone-reduction. The calibration coefficient results of the sludge yield formula indicated that Y_h was reduced from 0.331 g·g^-1 to 0.326 g·g^-1 (to MLVSS/COD m) by ozone treatment and K_d was increased from 0.046 d^-1 to 0.050 d^-1 at 75 mg·g^-1. The effluent quality of the SBR system was satisfactory when the sludge age was 10 d. The ozone dosage of 75 mg·g^-1 and sludge age of 10 d were selected as the appropriate process conditions, at which the excess sludge was reduced by 12%. The high-throughput sequencing results concluded that the microorganisms in the excess sludge after ozonation were different in phylum and genus. After ozone treatment, the abundance of Bacteroidetes increased by 1.2 times and the relative abundance of Proteobacteria with nitrification and denitrification ability decreased from 24% to 18%. The reduction in the abundance of nitrobacteria affected the denitrification capacity of the sewage treatment system, but the total effluent nitrogen still met the I B discharge standard of pollutants for municipal wastewater treatment plants. The relative abundance of Lactococcus increased from 0.4% to 21.6%. Simultaneously, the concentration of macromolecular organic substances in the EPS of the excess sludge increased from 40.6 mg·g^-1 to 54.6 mg·g^-1, while the CST increased from 15 s to 17 s after ozone treatment. The zeta potential decreased from -10.04 mV to -15.20 mV and the SVI of the excess sludge increased from 54 mL·g^-1 to 62 mL·g^-1, thereby indicating that the sedimentation performance and dewaterability were affected to some extent. However, the SS of the effluent and the solids content of the sludge cake after extraction did not change significantly, the system could still operate stably, and the subsequent dewaterability of the excess sludge was not significantly affected.