悬浮填料生物膜工艺的研究进展

悬浮填料生物膜工艺又称为移动床生物膜反应器工艺，是上世纪90年代初迅猛发展起来的一种新型水处理工艺．它既可以作为独立的生物处理系统，也能够与活性污泥法组合以增加后者的处理效能，还可以作为中高浓度工业废水的生物预处理手段．本文总结了悬浮填料生物膜工艺的流体力学、生化动力学规律、悬浮填料的开发现状，探讨了此工艺在市政生活污水、工业废水、低污染物浓度的水处理领域的研究和应用进展．进一步开发高效、廉价的功能型悬浮填料，提高填料的有效比表面积，优化与确定工艺和运行参数，将推动悬浮填料生物膜工艺在我国的全面应用．图3表1参64     

活性污泥吸附预处理重油裂化制气废水

利用剩余活性污泥对含有高浓度芳香族化合物的重油裂化制气废水进行预处理的研究并提出了合适的吸附条件。结果表明，活性污泥吸附预处理对COD和悬浮物有明显的去除效果，而且可以提高废水BOD5／COD的比值，另外还有降解芳香族化合物的作用，使进入生物处理系统的废水的可生物降解性有明显的改善。这一方法为利用普通废水生物处理系统中产生的剩余活性污泥来预处理难降解的工业废水提供了一条有效的途径。     

活性污泥系统处理苯酚废水的生物强化效果

通过性能测定观察到,菌株Candidasp.对苯酚具有较强的降解能力,因此选取来作为生物强化试验的模式菌株.通过不同接种量、不同苯酚初始浓度的比较实验,发现随着菌体加入量的增加,活性污泥系统获得的生物强化效果逐渐增强,随着初始底物浓度的增加,活性污泥系统的生物强化效果逐渐减弱,同时通过20d的长期实验发现,强化效果没有随时间减弱,而且比单独活性污泥系统经过20d驯化所得的降解能力高60%.图4参7     

仿生植物附着微生物膜对污染水体氮素迁移转化效能分析

通过室外及室内控制试验,研究5种常见填料作为原材料制成的仿生植物对污染水体氮素的去除性能,结果表明,仿生植物原材料的差异将直接影响其附着生物膜特性,其附着生物膜量、硝化强度、反硝化强度以及硝化细菌、反硝化细菌均表现为：软性填料﹥组合填料﹥悬浮填料﹥立体弹性填料﹥半软性填料。水深对仿生植物附着生物膜亦有不同程度的影响,其中生物膜量随水深的增加并未表现出明显的分层效应,而生物膜硝化作用强度、硝化细菌随水深的增加逐渐降低,但生物膜反硝化作用强度、反硝化细菌则随水深的增加则呈现出逐渐增加的趋势。5种不同材质的仿生植物对水体TN、NH4＋-N、NO3--N具有较好的去除效果,去除率表现为：软性填料﹥组合填料﹥悬浮填料﹥立体弹性填料﹥半软性填料﹥对照系统。同时,仿生植物种植密度也影响其对水体氮素的去除效果,表现为CK〈7株·m-3〈13株·m-3〈20株·m-3,研究结果将为仿生植物的野外实际应用及我国城市重污染河道水质原位修复提供技术支持。     

化学-生物絮凝污水处理工艺中微生物群落结构变化分析

利用分子生物学技术，直接从化学-生物絮凝工艺的活性污泥样品中提取DNA，对16S rDNA V3区进行PCR扩增，结合DGGE（变性浓度梯度凝胶电泳），分析了活性污泥中微生物群落结构，并对Shannon多样性指数进行分析讨论，通过研究指出系统中细菌数量的增加或减少．测定了活性污泥中部分菌种的16S rDNA V3区片段序列，通过NCBI（美国国立生物技术信息中心）基因库比对，初步确定细菌的属．结果表明，PCR—DGGE结合测序技术是一种完全可行的快速进行环境样品微生物研究的分析方法．图3表4参13     

投加硝化菌的活性污泥工艺硝化效率特性

研究了在活性污泥工艺中用投加硝化菌的方法提高硝化效率的特性，试验用富氮废水生成硝化污泥，并将其剩余硝化污泥投加于处理初沉市政污水的活性污泥工艺试验装置，研究结果表明，投加硝化菌能降低常规活性污泥工艺硝化的泥龄要求、改善硝化效果以及减少为低温稳定运行而增加的硝化反应器容积。     

Mo6+对活性污泥系统反硝化性能的影响

采用对比实验的方法,在不同初始硝酸盐氮和COD质量浓度的条件下,对人工模拟的活性污泥系统投加不同质量浓度的Mo6 ,以此考察Mo6 对活性污泥系统反硝化性能的影响。结果发现,Mo6 的质量浓度小于5mg?L-1以下时能够促进硝酸盐氮的去除,质量浓度为1mg?L-1时促进效果最好。Mo6 的质量浓度在4mg?L-1以下时,可以使COD去除效率增加,质量浓度为2mg?L-1时有最佳促进作用。Mo6 的质量浓度小于1g?L-1时可提高反硝化活性污泥的TTC-脱氢酶活性,过高质量浓度则表现出抑制作用。综合Mo6 的对硝酸盐氮和COD去除的影响规律以及对活性污泥TTC-脱氢酶活性的影响,认为Mo6 在质量浓度为1mg?L-1时对反硝化的促进作用最强。     

生物滤塔处理VOCs挂膜启动方法研究

通过中试规模的生物滤塔的两种填料挂膜方法的试验研究，表明填料接种后可以直接壮入生物滤塔，进行直接通气挂膜，该方法符合生物膜在载体表面的固定机理和形成过程，可在较短的时间内完成系统启示。本文同时论述了影响挂膜的几个因素。     

膜生物反应器内泥水混合液可过滤性的研究

膜生物反应器是一种新兴的水处理技术，但目前膜造价较高，导致运行费用较高，因此，提高膜通量的各种技术措施具有重要的意义。文中引入静态泥水混合液过滤试验，通过对取自运转中ＭＢＲ的活性污泥混合液的过滤实验结果分析，着重阐述了影响活性污泥可过滤性的影响因素，并指出在维持ＭＢＲ的运行中，改善活性污泥性状是一个不可忽略的方面。     

小球藻和活性污泥共培养体系处理养殖废水

为提高藻菌共培养体系对养殖废水的处理效果,优选最佳的共培养方式和处理时间,研究普通小球藻(UTEX2714)和活性污泥在5种共培养体系中对污染物的去除效率[游离小球藻和游离活性污泥(Sc+Sa),游离小球藻和固定化活性污泥(Sc+Ia),游离活性污泥和固定化小球藻(Sa+Ic),固定化小球藻和固定化活性污泥(Ic+Ia),藻菌共固定[I(c+a)](藻菌:小球藻和活性污泥),考察体系的稳定性和胶球的可重复利用性.结果显示:游离活性污泥和固定化小球藻共培养体系在48 h对养殖废水的处理效果最佳,对氨氮(NH4+-N)、总氮(TN)、总磷(TP)、化学需氧量(COD)的去除率分别为93.89%、91.95%、97.53%、93.41%;细胞比增长速率0.214/h,均大于其他4组共培养体系.稳定性试验中胶球在使用一个周期(48 h)后用CaCl2再次加固可提高系统的稳定性,可稳定运行8个周期,NH4+-N、TP的去除率分别在81.59%-93.69%、84.23%-98.74%.本研究表明Sa+Ic共培养体系运行48 h能有效处理养殖废水;稳定性试验中,加固方法能有效保证系统稳定运行;结果可为藻菌共培养体系处理水产养殖废水的实际应用提供基础数据.(图6表3参38附图2附表1)     

不同pH值条件下悬浮载体SBR反应器处理污染河水的试验

研究了不同pH值条件下悬浮载体SBR反应器处理污染河水的脱氮性能和微生物活性。结果表明,初始pH为7.0时,悬浮载体SBR反应器处理污染河水的脱氮性能最好,NH4^＋-N和TN去除率分别为100%和36.6%。在初始pH 7.0时,悬浮相和附着相污泥亚硝化活性均达到最高,分别为6.81 mgNH4＋/（gMLVSS.h）和5.42 mgNH4^＋/（gMLVSS.h） 悬浮相污泥在pH 9.0时硝化性能最好,达到2.31 mgNO2^-/（gMLVSS.h）,而附着相污泥在pH 8.0时硝化性能达到最佳状态,为1.03 mgNO2^-/（gMLVSS.h） 在pH 8.0时,悬浮相和附着相污泥反硝化活性最强,分别到达13.98mg NO3^-/（gMLVSS.h）和12.72 mgNO3^-/（gMLVSS.h）。     

Catalase activity of activated sludge

Catalase activity of mixed liquor suspended solids of aeration tank of activated sludge plants in Milwaukee, WI, was measured in sonicated samples. Catalase activity varied in the samples of mixed liquor suspended solids collected from the head and end of the aeration tanks; in return activated sludge; and in waste activated sludge. Catalase activity decreased in mixed liquor suspended solids, on prolonged aeration (8 days), in the absence of added sewage. Volatile suspended solids and catalase activity seemed to bear a relationship.     

Transport of Sewage Sludge in a Mixed Water Column

Sewage sludge from four publicly-owned treatment works was sampled and characterized in terms of parameters affecting transport at the 106-mile deep ocean disposal site as part of the US Environmental Protection Agency's site monitoring programme. Samples from treatment plants in Passaic Valley, Rahway, and Elizabeth, New Jersey and New York City were characterized in terms of dynamic size distribution, suspended solids and density. the transport characteristics of sludge particles were measured using a 2 metre computer-interfaced laboratory settling column. Experiments were conducted at constant salinity (35 ppt) while varying hydrodynamic mixing, sludge type and concentration using a modified factorial experimental design. Hydrodynamic power dissipation was varied so that the vertical dispersion and rms fluid shear rate ranged between 0-6 cm²S^-1 and 0-30s^-1 respectively. Results indicate that at least 80% of suspended sludge particles will eventually settle under mixed conditions. the average settling velocities ranged between 0.05-4.05 × 10^-3 cm ^s-1. Shear rates above 15 s^-1 inhibited sludge settling due to aggregate breakup and boundary effects, but at a lower shear rate, differential settling and fluid shear were the dominant transport mechanisms. Sludge dilution (1/500-1/5000) had a limited effect on the settling rate. Results from this study can be used to calibrate particle transport models to determine the fate of sludge disposed at an ocean disposal site.     

Transport of Sewage Sludge in a Mixed Water Column

Abstract

Sewage sludge from four publicly-owned treatment works was sampled and characterized in terms of parameters affecting transport at the 106-mile deep ocean disposal site as part of the US Environmental Protection Agency's site monitoring programme. Samples from treatment plants in Passaic Valley, Rahway, and Elizabeth, New Jersey and New York City were characterized in terms of dynamic size distribution, suspended solids and density. the transport characteristics of sludge particles were measured using a 2 metre computer-interfaced laboratory settling column. Experiments were conducted at constant salinity (35 ppt) while varying hydrodynamic mixing, sludge type and concentration using a modified factorial experimental design. Hydrodynamic power dissipation was varied so that the vertical dispersion and rms fluid shear rate ranged between 0-6 cm²S^?1 and 0-30s^?1 respectively. Results indicate that at least 80% of suspended sludge particles will eventually settle under mixed conditions. the average settling velocities ranged between 0.05-4.05 × 10^-3 cm ^s-1. Shear rates above 15 s^?1 inhibited sludge settling due to aggregate breakup and boundary effects, but at a lower shear rate, differential settling and fluid shear were the dominant transport mechanisms. Sludge dilution (1/500-1/5000) had a limited effect on the settling rate. Results from this study can be used to calibrate particle transport models to determine the fate of sludge disposed at an ocean disposal site.     

Dehydrogenases activity of activated sludge

A study of dehydrogenases activity of activated sludge, return activated sludge, and waste activated sludge from three sewage treatment plants was made. Dehydrogenases activity and protein content of the mixed liquor varied along the aeration basin. Chromium chloride and zinc sulfate were found to be inhibitory to dehydrogenases activity. Return activated sludge and waste activated sludge, in spite of higher content of volatile suspended solids, contained lower dehydrogenases activity. Return activated sludge when kept without aeration and addition of sewage, showed higher dehydrogenases activity; and on aeration, but without addition of sewage, it showed progressively lower dehydrogenases activity.     

Advanced nitrogen and phosphorus removal in A2O-BAF system treating low carbon-to-nitrogen ratio domestic wastewater

A laboratory-scale anaerobic-anoxic-aerobic process (A²O) with a small aerobic zone and a bigger anoxic zone and biologic aerated filter (A²O-BAF) system was operated to treat low carbon-to-nitrogen ratio domestic wastewater. The A²O process was employed mainly for organic matter and phosphorus removal, and for denitrification. The BAF was only used for nitrification which coupled with a settling tank Compared with a conventional A²O process, the suspended activated sludge in this A²O-BAF process contained small quantities of nitrifier, but nitrification overwhelmingly conducted in BAF. So the system successfully avoided the contradiction in sludge retention time (SRT) between nitrifying bacteria and phosphorus accumulating organisms (PAOs). Denitrifying phosphorus accumulating organisms (DPAOs) played an important role in removing up to 91% of phosphorus along with nitrogen, which indicated that the suspended activated sludge process presented a good denitrifying phosphorus removal performance. The average removal efficiency of chemical oxygen demand (COD), total nitrogen (TN), total phosphorus (TP), and NH ₄ ⁺ -N were 85.56%, 92.07%, 81.24% and 98.7% respectively. The effluent quality consistently satisfied the national first level A effluent discharge standard of China. The average sludge volume index (SVI) was 85.4 mL·g^?1 additionally, the volume ratio of anaerobic, anoxic and aerobic zone in A²O process was also investigated, and the results demonstrated that the optimum value was 1:6:2.     

采用ICEAS工艺进行瓦房店市污水处理厂设计

在调研的基础上，成功地应用ICEAS（Intermittent Cyclic Extended Activated Sludge)工艺进行瓦房店市污水处理厂设计。实践证明，该工艺占有占地面积小、处理效果好、工艺简单、运行稳定，对污水水质适应性强、耐冲击负荷、污泥龄长、污泥沉降性能好，剩余污泥少等优点。     

活性污泥的絮体结构模型

采用Motic数码显微镜观察SRT为3 d和15 d的活性污泥絮体以及它们的LEPS和TEPS絮凝污泥悬浮液形成的生物絮体的结构。结果表明,高SRT（15 d）活性污泥絮体较低SRT（3 d）活性污泥絮体的颜色深且密实;同一活性污泥中,内层的絮体结构较外层的絮体结构密实,细菌细胞与菌胶团之间的结合更为紧密。最后,结合絮体结构图片,从大分子作用力的角度,提出了活性污泥絮体结构模型,以形象地描述不同SRT活性污泥EPS及其表面性质变化对活性污泥絮凝沉降性能的影响。     

Performance of bioferric-submerged membrane bioreactor for dyeing wastewater treatment

Adding iron salt or iron hydroxide to sludgemixed liquor in an aeration tank of a conventional activated sludge processes (bioferric process) can simultaneously improve the sludge’s filterability and enhance the system’s treatment capacity. In view of this, Fe(OH)₃ was added to a submerged membrane bioreactor (SMBR) to enhance the removal efficiency and to mitigate membrane fouling. Bioferric process and SMBR were combined to create a novel process called Bioferric-SMBR. A side-by-side comparison study of Bioferric-SMBR and common SMBR dealing with dyeing wastewater was carried out. Bioferric-SMBR showed potential superiority, which could enhance removal efficiency, reduce membrane fouling and improve sludge characteristic. When volumetric loading rate was 25% higher than that of common SMBR, the removal efficiencies of Bioferric-SMBR on COD, dye, and NH₄ ⁺-N were 1.0%, 9.5%, and 5.2% higher than that of common SMBR, respectively. The trans-membrane pressure of Bioferric-SMBR was only 36% of that in common SMBR while its membrane flux was 25% higher than that of common SMBR. The stable running period in Bioferric-SMBR was 2.5 times of that in common SMBR when there was no surplus sludge discharged. The mixed liquor suspended solids concentration of Bioferric-SMBR was higher than that of common SMBR with more diversified kinds of microorganisms such as protozoans and metazoans. The mean particle diameter and specific oxygen uptake rate of Bioferric-SMBR were 3.10 and 1.23 times the common SMBR, respectively.