采用水力剪切强度优化短程硝化反硝化除磷颗粒污泥性能  

Optimization of short-cut nitrification and denitrification phosphorus removal particle sludge based on hydraulic shear strength

作　　者：李冬[1] 高鑫[1] 陈昊[1] 杨杰[1] 张杰[1,2] LI Dong;GAO Xin;CHEN Hao;YANG Jie;ZHANG Jie(Key Laboratory of Beijing Water Quality Science and Water Environment Recovery Engineering(Beijing University of Technology),Beijing 100124,China;State Key Laboratory of Urban Water Resource and Environment(Harbin Institute of Technology),Harbin 150090,China)

机构地区：[1]水质科学与水环境恢复工程北京市重点实验室(北京工业大学),北京100124 [2]城市水资源与水环境国家重点实验室(哈尔滨工业大学),哈尔滨150090

出　　处：《哈尔滨工业大学学报》2023年第6期10-18,共9页Journal of Harbin Institute of Technology

基　　金：北京高校卓越青年科学家计划(BJJWZYJH01201910005019)。

摘　　要：短程硝化反硝化除磷具有氧气消耗量小、碳源需求低以及污泥产量低等优势,但好氧颗粒污泥随着运行因粒径过大容易解体失稳。为解决失稳问题并保证反硝化聚磷菌(denitrifying phosphate accumulating organisms,DPAOs)具备充足的缺氧区,将长期以人工配水培养的颗粒污泥作为种泥,通过优化水力剪切强度调控粒径分布,实现处理生活污水的稳定运行,并探究不同水力剪切强度对颗粒结构的影响。结果表明,具有最优同步脱氮除磷性能且颗粒结构致密的粒径范围为800~1400μm,通过调控水力剪切强度至1435.2可将这一粒径范围内的颗粒占比提高到53.39%。待颗粒粒径稳定后,出水COD远低于50 mg/L,TN去除率达90%左右,出水TN质量浓度约为4.28 mg/L,TP平均去除率为93.45%,出水TP质量浓度均在0.5 mg/L以下。此外,三维荧光结合平行因子对胞外聚合物的分析表明,提高水力剪切强度能够降低腐殖酸的质量分数并提高蛋白质的占比,有利于优化颗粒沉降性能以及提高致密性。通过优化粒径范围,利用自身缺氧区富集DPAOs并逐渐淘汰亚硝酸盐氧化菌,同时避免了丝状菌膨胀现象,稳定实现了对生活污水的短程硝化反硝化脱氮除磷处理。Short-cut nitrification and denitrification phosphorus removal has the advantages of low oxygen consumption,low carbon source demand,and low sludge yield,but aerobic granular sludge(AGS)is prone to disintegration and instability due to large particle size.In order to solve the problem of instability and ensure sufficient anoxic zone for denitrifying phosphate accumulating organisms(DPAOs),long-term cultivated granular sludge with artificial water distribution was used as seed sludge,and the particle size distribution was regulated by optimizing hydraulic shear strength,so as to realize the stable operation of domestic sewage treatment and explore the influence of hydraulic shear strength on particle structure.Results showed that the particle size range with optimal simultaneous nitrogen and phosphorus removal performance and dense particle structure was 800-1400μm.By adjusting the hydraulic shear strength to 1435.2,the proportion of particles in this size range was increased to 53.39%.When the granulation reached stable,the effluent COD concentration was maintained below 50 mg/L,the TN removal rate was about 90%,the effluent TN concentration was 4.28 mg/L,the average removal rate of TP was 93.45%,and the effluent TP concentration was below 0.5 mg/L.In addition,the analysis of extracellular polymeric substances(EPS)by excitation-emission matrix(EEM)combined with parallel factor(PARAFAC)showed that increasing hydraulic shear strength could reduce the content of humic acid and increase the proportion of protein,which was conducive to optimizing particle sedimentation performance and improving compactness.By optimizing the particle size range,the larger anoxic zone of granules could be used to enrich DPAOs and gradually eliminate nitrite oxidizing bacteria,avoiding the expansion of filamentous bacteria,and realizing stable short-cut nitrification,denitrification,nitrogen,and phosphorus removal of domestic sewage.

关 键 词：颗粒粒径 水力剪切强度 胞外聚合物 生活污水 短程硝化反硝化除磷 

分 类 号：X703[环境科学与工程—环境工程]