Characterization of dissolved organic matter in urban sewage using excitation emission matrix fluorescence spectroscopy and parallel factor analysis

Wastewater dissolved organic matter (DOM) from different processing stages of a sewage treatment plant in Xiamen was characterized using fluorescence and absorption spectroscopy. Parallel factor analysis modeling of excitation-emission matrix spectra revealed five fluorescent components occurring in sewage DOM: one protein-like (C1), three humic-like (C2, C4 and C5) and one xenobiotic-like (C3) components. During the aerated grit chamber and primary sedimentation tank stage, there was only a slight decrease in fluorescence intensity and the absorption coefficient at 350 nm (a350). During the second aeration stage, high concentration of protein-like and short-wavelength-excited humic-like components were significantly degraded accompanied by significant loss of DOC (80%) and a350 (30%), indicating that C1 and C2 were the dominant constituents of sewage DOM. As a result, long-wavelengthexcited C4 and C5 became the dominant humic-like components and the DOM molecular size inferred from the variation of spectral slope S (300–650 nm) and specific absorption (a280/DOC) increased. Combination use of Fmax of C1 and the ratio of C1/C5, or a350 may provide a quantitative indication for the relative amount of raw or treated sewage in aquatic environment.     

金刚石膜电极消毒处理医院污水的试验研究

以掺硼金刚石(BDD)作电极的自制电解槽装置处理医院污水的消毒效果。在全回流处理模式下消毒处理医院废水,采用多管发酵法测定粪大肠菌群数。掺硼金刚石(BDD)作电极,在电极间距为2mm、医院污水Cl-浓度为200mg/L、pH值在7.0～8.0范围内、电流密度8mA/cm2、接触时间≥9s的条件下,对医院污水粪大肠菌群的去除率最佳,出水满足《医疗机构污水排放标准值》粪大肠菌群数均不得超过500MPN/L。掺硼金刚石(BDD)作电极的自制电解槽装置处理医院污水不需要添加化学药剂,对粪大肠菌群消毒效果好。     

SBR法在小区生活污水处理上的应用

SBR法工艺流程简单、造价低，主体设备只有一个序批式间歇反应器，无二沉池、污泥回流系统，初沉池也可省略，布置紧凑、占地面积省，可根据水质、水量情况灵活运行，具有良好的脱氮除磷效果。而生活小区土地面积有限，景观要求高。通过采用SBR法处理小区生活污水，处理效果好，COD、BOD、SS、TNP和NH3-N去除率分别达到88．75％、87．50％、86．10％、84．50％和51．70％，且都达到GB8978—1996中一级排放标准。     

The effect of landfill leachate composition on organics and nitrogen removal in an activated sludge system with bentonite additive

A pre-denitrification activated sludge system (AS) without internal recycle was used in lab-scale studies of landfill leachate treatment. A bentonite supplement at a ratio of 1:4 (mineral : biomass) was used to ensure high sludge settling levels and to serve as a micro-organisms carrier. The system was operated within different parameters such as hydraulic retention time (HRT), ammonia loading rate (ALR) or external recycle ratio, which was adapted to treat varying leachate concentrations of COD and ammonia, ranging from 1020 to 2680 mgO(2)l(-1) and 400-890 mgNH(4)-Nl(-1) respectively. The nitrification was complete and ammonia oxidation reached 99%; this was obtained while the ALR did not exceed 0.09 g NH(4)(+)-Ng(-1)MLVSS d(-1) and HRT was not lower than 1 day (in the aeration reactor). The performance of denitrification was successfully improved by controlling the external recycle rate, when the BOD(5)/N ratio in the raw leachate was 4.1. Consequently, N-removal of up to 80% was achieved. A 10-fold decrease in the denitrification rate was obtained at a BOD(5)/N ratio of 0.5. The efficiency of COD removal varied significantly from 36% to 84%. The positive effect of bentonite addition was determined and is discussed based on preliminary studies. The experiments were carried out in fill-and-draw activated sludge with bentonite; the biomass ratio was 1:2. The activated sludge with bentonite was fed with a synthetic high ammonia and organic-free medium.     

我国城市污水工业回用的现状及存在问题的探讨

略述了近几年来我国城市污水工业回用的一些成功经验 ,提出了城市污水工业回用中存在的几个主要问题及其对策 ,展望了我国在这一领域的发展前景。     

华南地区11种高等水生维管植物净化城镇污水效益评价

采用定标、单项评分和综合评价的方法，从净化能力、抗逆性、管理、资源化程度和景观５方面，对华南地区筛选出的１１种高等维管植物净化城镇污水效益进行了评价。结果表明：黑藻、假马齿苋和水筛对污水的净化能力与风眼莲相当，而综合效能优于风眼莲。评价结果为城镇污水的处理提供了新的资料。     

流量分配对短程生物脱氮过程中N2O产生的影响

利用SBR反应器,通过在线pH曲线控制好氧-缺氧反应时间,成功实现了短程生物脱氮,并考察了分段进水条件下流量分配对SBR反应器运行性能及N2O产量的影响.结果表明,与原水分2次在不同阶段等量加入反应器的二段进水方式相比,原水分3次等量进入反应器的三段进水方式能够有效降低脱氮过程中外碳源投加量和氧化亚氮产量;氧化亚氮主要产生于硝化过程,反硝化过程能够将硝化阶段积累的N2O还原至N2.2次、3次等量进水条件下,生物短程脱氮过程中乙醇投加量分别为0.8和0.6 mL,N2O释放量分别为8.86和5.05 mg·L-1(以N计).硝化过程中NO-2-N的积累是导致系统N2O产生的主要原因.     

颗粒活性炭诱导亚硝化污泥快速颗粒化

采用两组平行SBR反应器,R1反应器投加颗粒活性炭,R2反应器不投加,其他运行参数保持一致.在常规生活污水中投加氨氮作为进水,研究颗粒活性炭对亚硝化颗粒污泥形成的影响.结果表明,在颗粒形成初期,投加的颗粒活性炭作为初始晶核,节约了小颗粒的形成时间,R1反应器仅22d便实现污泥颗粒化,而R2反应器运行38d才形成颗粒;同时,在整个运行阶段,R1反应器中的胞外聚合物(EPS)含量,尤其是其中的蛋白质(protein, PN)含量,明显高于R2反应器的,进一步证实颗粒活性炭的投加有利于亚硝化颗粒污泥的快速形成.除此之外,R1反应器中的氨氧化率和亚硝化率相对较高,且波动幅度小,表明颗粒活性炭的投加有助于维持亚硝化颗粒污泥处理效果的稳定性.     

高径比对生活污水好氧颗粒污泥系统的影响

采用3组高径比分别为3：1,4.5：1和6：1的SBR反应器（R1,R2,R3）,以实际生活污水为进水并接种污水处理厂二沉池的回流污泥,研究SBR高径比对生活污水好氧颗粒污泥形成,同步去除碳,氮,磷性能的影响.结果表明,R1,R2,R3分别历时42,35和28d启动成功;颗粒污泥培养成熟后,其平均粒径逐渐趋于稳定,分别可达750,900,1100μm.启动阶段,R1,R2,R3对总氮的去除率分别为66%,61%,62%;颗粒污泥成熟后,R1,R2和R3出水均满足《城镇污水处理厂污染物排放标准》一级A标准,总氮去除率分别为79%,85%,91%,总磷去除率分别为91%,93%,94%,COD去除率分别为89%,92%,93%.进一步分析表明,在本试验研究范围内,SBR高径比增大有利于好氧颗粒污泥的形成,且利于增大颗粒粒径,进而提高沉淀性能和同步去除碳,氮,磷的性能.     

污水处理用曝气转盘材料的研究

根据污水处理用曝气转盘需要的特定性能，研究设计了一种与其相匹配的预混合材料，已成功使用于多座污水处理场