硝化速率法用于活性污泥活性测试的研究

以城市污水厂回流污泥中的硝化细菌(氨氧化细菌和亚硝酸盐氧化细菌)为受试生物,HgCl2为标准毒性物质,通过对两组实验--氨氧化速率实验(NH 4-N→NO-2-N)和亚硝酸盐氧化速率实验(NO-2-N→NO-3-N)的研究表明,氨氧化细菌对HgCl2的灵敏度(IC50=0.034 mmol/L)明显高于亚硝酸盐氧化细菌(IC50=0.20 mmol/L).氨氧化速率法测试活性污泥活性时,使用NH 4-N或NO-X-N指标需要120 min或更长的时间,但使用NO-2-N指标仅需30 min就可完成测试,而且结果重现性要比NH 4-N和NO-X-N好,其变异系数CV为5.9 %.     

活性污泥总DNA提取方法的比较

从处理某制药废水的MBR反应器中采集活性污泥,评价不同DNA提取方法对其总DNA提取效率的影响。DNA提取分细胞裂解和DNA纯化2步,对细胞裂解比较了珠磨匀浆法、反复冻融法、十二烷基磺酸钠（sodium dodecyl sulfate,SDS）裂解法等7种方法;对DNA纯化比较了酚/氯仿纯化法和胶回收纯化法。结果表明,SDS裂解法、酚氯仿纯化法最优。通过条件优化实验,确定SDS裂解酚/氯仿纯化法在污泥量1.1 g,10 000 r/min离心5 min的操作条件下,获得的DNA产量（10 774 μg/g泥重）和纯度（OD₂₆₀∶OD₂₈₀=1.84）等综合指标最好。     

A comparison of five rapid direct toxicity assessment methods to determine toxicity of pollutants to activated sludge

Five rapid direct toxicity assessment methods were used in three European partner countries to determine the toxicity of single toxicants, mixed toxicants and real industrial wastes. The final aim was to protect microbial degradation of organic wastes in biological treatment processes and hence enhance the quality of treated effluents to be discharged to the environment. Nitrification inhibition, Respirometry, Adenosine triphosphate luminescence and Enzyme inhibition were tested utilising activated sludge as the testing matrix. The Vibrio fischeri toxicity test was used as a surrogate to compare the various microbial bioassays. The IC50 (toxicant concentration eliciting a 50% inhibitory effect) was determined for a number of pollutants including single toxicants Cd, Cr, Cu, Zn, 3,5-dichlorophenol, toluene and linear alkylbenzenesulphonate (LAS); a standard mixture of metals and LAS; a standard mixture of organics and LAS, and 16 industrial effluents. The V. fischeri bioassay was also chosen in order to assess quality control of toxicant preparation during testing in the different laboratories of the partner countries. Comparisons of sensitivity, cost of implementation, cost per test, relevance, and ease of use were made. The most sensitive bioassays were V. fischeri and Nitrification inhibition, however, this depended in the main on the pollutant and mixtures tested. It is recommended that during assessment of wastewater toxicity a suite of tests be used rather than reliance on one particular test.     

应用于PCR-DGGE分析的活性污泥微生物总DNA提取方法比较

探讨适用于PCR-DGGE分析研究的活性污泥细菌和真菌的DNA提取方法。采用5种方法提取活性污泥微生物基因组DNA,以DNA纯度、含量、片段大小及DGGE条带多样性作为考察指标评价提取方法的优劣,以确定最佳实验方案。紫外吸收法和琼脂糖凝胶电泳结果显示,试剂盒法提取的DNA含量最低,其余4种方法获得的DNA含量无显著差异,就DNA纯度而言,试剂盒法最优;除高温裂解法对真菌细胞壁裂解效果较差外,其他4种方法均能不同程度地裂解细菌和真菌细胞;DGGE结果表明,高温裂解法获得的细菌条带最多,基于SDS的细胞裂解法得到的真菌条带最多。综合分析,高温裂解法更适合于活性污泥中细菌的PCR-DGGE分析,基于SDS的细胞裂解法则更适合于污泥中真菌的PCR-DGGE分析。     

测定城市生活污泥中重金属的酸消解方法研究

采用HNO3-HC1O4-HF、HNO3-HC1O4、王水-HC1O4、HNO3等不同的酸消解方法对城市生活污泥进行消解。通过对这4种消解方法进行实验比较及对Cu、Ni、Zn三种金属元素浓度的测定,发现HNO3-HC1O4是适合城市生活污泥特点的消解方法。     

活性污泥硝化过程的动态响应信号

把pH值在线监测与药品自动投加系统与已开发的混合呼吸测量仪集成,组成自动呼吸-滴定测量仪,同时测得废水生物处理过程溶解氧（DO）、pH、氧气利用速率（OUR）和质子变化速率（HVR）。分别监测了只投加NH4＋-N底物的活性污泥硝化过程和实验室脱氮除碳SBR曝气阶段的DO/pH响应,结果显示,两信号呈一定规律变化,在反应...     

盐度对活性污泥硝化功能的影响

利用批量试验研究了盐度对常规活性污泥(非耐盐污泥)硝化功能的影响;通过逐步提高试验水的NaCl浓度驯化活性污泥,考察了驯化污泥的硝化功能;并进一步研究了适应于某NaCl浓度的耐盐硝化菌在受到盐度冲击时,其硝化功能的变化.结果表明,常规活性污泥中的硝化菌对盐度较敏感,当试验水中的NaCl质量浓度达到10.0 g/L时,污泥比硝化速率降低86%;通过逐步提高试验水的NaCl浓度对活性污泥进行长期驯化,可以驯化出耐盐硝化菌,耐盐污泥的比硝化速率接近于常规活性污泥的比硝化速率;适应于某NaCl浓度的耐盐硝化菌在受到盐度冲击时,NaCl浓度突然增加会对其产生更强的抑制作用.     

城市综合污水处理厂污泥对Daphnia magna 的急性毒性与毒物特征

以城市综合污水处理厂污泥的浸提液对Daphnia magna的24h急性毒性为指标，研究了污泥放置时间与其毒性的关系。结果表明，污泥对Daphnia magna的急性毒性随旋转时间的增加逐渐增大，但在旋转两个月后毒性趋于稳定。对放置3d和84d的污泥，利用TIE（毒性鉴别评价）方法对其浸提液进行了毒物特性鉴别，结果表明，放置3d的污泥，浸提液毒性主要由酸性条件下易挥发的物质引起，放置84d的污泥浸提液中的毒物主要为金属离子和易与酸碱反应的物质。     

盐度对活性污泥驯化前后硝化特性的影响

通过批量试验系统研究了盐度对常规活性污泥硝化作用的影响以及污泥在含盐环境中经过驯化后其硝化功能的变化.试验结果表明,硝化菌比亚硝化菌对盐度更敏感,废水中含盐浓度为5 g/L时,对常规活性污泥中的亚硝化菌影响不大,硝化菌会受到一定程度的抑制;当含盐浓度超过10 g/L时,硝化菌和亚硝化菌均会受到严重抑制;含盐浓度大于30 g/L时,亚硝化菌和硝化菌已经完全受到抑制.在污泥驯化初期,耐盐硝化菌群数量较少,比硝化速率较低,硝化产物中亚硝态氮大量积累;随着驯化时间的延长,耐盐硝化菌群数量增加,比硝化速率增加,亚硝态氮累积量减少.污泥经过驯化后,硝化菌群可以逐渐适应高盐环境,在含盐浓度为30 g/L时硝化反应仍能进行.     

硫酸活化市政污泥对亚甲基蓝的吸附

采用市政剩余污泥作为原料,以硫酸作为活化剂制备吸附剂,并将其应用到含亚甲基蓝废水处理中。系统地研究了溶液初始pH值、亚甲基蓝初始浓度和吸附时间等因素对硫酸活化市政污泥吸附性能的影响。研究结果表明,在吸附剂投加量2 g/L,pH7.5,温度293 K条件下,硫酸活化市政污泥对亚甲基蓝的最大吸附量为38.4794 mg/g。吸附动力学和热力学研究结果表明,吸附剂对亚甲基蓝的吸附过程可用准二级动力学模型(R2=0.9910)、Freundlich吸附等温式(R2=0.9935)来描述。颗粒内扩散速率也是其吸附反应限制因素,但不是惟一限制因素。该研究表明,硫酸活化剩余污泥可以作为含亚甲基蓝染料废水的处理材料。     

铬离子对SBR工艺活性污泥毒性作用研究

针对重金属铬离子对SBR工艺系统中活性污泥的毒性作用,通过检测不同初始污泥容积指数(SVI)下SBR工艺活性污泥在不同铬负荷下的COD值、挥发性污泥浓度以及受铬离子影响的污泥容积指数(SVI),研究重金属铬离子对活性污泥的毒性作用以及对SBR工艺系统处理污水的影响。研究表明,重金属铬离子会导致SBR工艺系统出水COD升高;将铬离子对活性污泥的毒性作用按照挥发性污泥(MLVSS)铬负荷可划分为耐受范围、非耐受范围、细胞失活范围以及细胞分解范围。耐受范围铬负荷低于约30 mg Cr3+/gMLVSS,此范围内铬离子对于活性污泥的毒性作用不大,不致于导致系统出水水质变差;非耐受范围铬负荷在约30~65 mg Cr3+/g MLVSS,在铬离子作用下系统出水COD值明显高于对照系统;细胞失活范围铬负荷在约70~100 mg Cr3+/gMLVSS范围内,SVI大幅下降,微生物部份死亡和失活,出水COD尽管有一些下降,但与进水COD相比差不了多少;细胞分解范围铬负荷在约100 mg Cr3+/gMLVSS以上,微生物大量死亡,部分死亡细胞分解,系统出水COD值因微生物的死亡分解而超出进水COD值,受铬离子影响的系统SVI值大幅度降低。     

Evaluation of the persistence of micropollutants through pure-oxygen activated sludge nitrification and denitrification.

The persistence of pharmaceuticals, hormones, and household and industrial chemicals through a pure-oxygen activated sludge, nitrification, denitrification wastewater treatment facility was evaluated. Of the 125 micropollutants that were tested in this study, 55 compounds were detected in the untreated wastewater, and 27 compounds were detected in the disinfected effluent. The persistent compounds included surfactants, fire-retardant chemicals, pesticides, fragrance compounds, hormones, and one pharmaceutical. Physical-chemical properties of micropollutants that affected partitioning onto wastewater solids included vapor pressure and octanol-water partition coefficients.     

Comparison of mechanical pretreatment methods for the enhancement of anaerobic digestion of pulp and paper waste activated sludge

The conventional anaerobic digestion process, requiring long solids retention times (SRTs) to digest solids, is currently viewed as impractical for the pulp and paper industry because of high capital costs associated with the construction of new digesters. Recent developments in sludge solubilization technology could be promising in reducing digester size, which also allows for the potential use of decommissioned tanks, both of which can reduce the capital cost. Three pretreatment technologies for use with anaerobic digestion were tested on laboratory-scale to investigate their feasibility. The SRTs in all three digesters systematically decreased from 20 to 3 days. The reference digester was fed waste activated sludge (WAS) to serve as the control at the same SRTs. The other digesters were fed WAS that had been preconditioned using mechanical shearing, sonication, or high-pressure homogenization technology. Anaerobic digestion with high-pressure homogenization produced as much methane at 3-day mean SRT as that from the reference digester operated at 20-day SRT. Therefore, a new digester can theoretically be 85% smaller than a conventional digester. An added benefit of WAS to methane conversion is the recovery of nutrients nitrogen and phosphorus.     

城市污泥微波干化工艺及干化特性研究

采用微波和烘箱结合及全程烘箱2种方式对城市污泥干化进行对比研究,考察了不同粒径、微波干化预处理、预处理时间及烘箱温度对污泥干燥特性的影响。结果表明,同一温度条件下,微波预处理时间越长,污泥干化速率越快。最优条件下,全程烘箱污泥达到最大干化速率的含水率为77%。微波干燥污泥具有时间短、干燥速率大的特点,微波和烘箱结合对比全程烘箱干化速率高且能耗低。     

Biodegradation in laboratory activated sludge plants and aquatic toxicity of herbicides

The biodegradation and the aquatic toxicity of four herbicides (isoproturon, terbuthylazine, mecoprop, metamitron) were investigated. Laboratory activated sludge plants were used for biodegradation experiments. The biodegradation of mecoprop reached nearly 100%, the other herbicides were not eliminated by biodegradation. The acute Daphnia magna 24-h assay, the algal 72-h inhibition test, and the recently developed lemna growth inhibition 7-d test were applied to evaluate the biological effects of herbicides as original substances. EC 50 and EC 10 values were determined. Algal and lemna test show that isoproturon and terbuthylazine are both much more toxic than mecoprop and metamitron. Daphnids are generally less sensitive against herbicides than plants. Biodegradation and toxicity test were coupled for mecoprop to assess biological long-term effects of possible biodegradation products of this herbicide. The effluents of the laboratory activated sludge units were used in toxicity tests (Daphnia magna 21-d reproduction test, lemna growth inhibition 7-d test). No inhibiting effect on the tested organisms was observed.     

Solubilization of municipal sewage waste activated sludge by novel lytic bacterial strains

Extracellular polymeric substances (EPS) are an extracellular matrix found in sludge which plays a crucial role in flocculation by interacting with the organic solids. Therefore, to enhance pretreatment of sludge, EPS have to be removed. In this study, EPS were removed with a chemical extractant, NaOH, to enhance the bacterial pretreatment. A lysozyme secreting bacterial consortium was isolated from the waste activated sludge (WAS). The result of density gradient gel electrophoresis (DGGE) analysis revealed that the isolated consortium consists of two strains. The two novel strains isolated were named as Jerish03 (NCBI accession number KC597266) and Jerish 04 (NCBI accession number KC597267) and they belong to the genus Bacillus. Pretreatment with these novel strains enhances the efficiency of the aerobic digestion of sludge. Sludge treated with the lysozyme secreting bacterial consortium produced 29 % and 28.5 % increase in suspended solids (SS) reduction and chemical oxygen demand (COD) removal compared to the raw activated sludge (without pretreatment) during aerobic digestion. It is specified that these two novel strains had a high potential to enhance WAS degradation efficiency in aerobic digestion.     

流态对活性污泥硝化性能及菌群结构的影响

生化反应器流态会影响基质分布,从而影响反应器内微生物的性能与菌群结构。在相同氮负荷下运行SBR和CSTR以对比分析2种典型流态(推流式和完全混合式)对活性污泥中硝化菌性能及其菌群结构的影响。结果表明,SBR中,氨氧化速率(AUR)和亚硝酸盐氧化速率(NUR)分别为(16.55±2.05)mg N/(L·g VSS·h)和(15.33±2.02)mg N/(L·g VSS·h),CSTR中AUR和NUR分别为(10.13±0.73)mg N/(L·g VSS·h)和(9.34±2.56)mg N/(L·g VSS·h);SBR中,氨氧化菌(AOB)和亚硝酸盐氧化菌(NOB)含量分别为(3.4±0.3)%和(5.4±1.2)%,优势菌分别为Nitrosomonas europaea-Nitrosococcus mobilis lineage和Nitrobacter,CSTR中,AOB和NOB含量分别(3.1±0.4)%和(6.8±1.1)%,优势菌分别为Nitrosospira和Nitrospira。虽然2个流态下的硝化菌含量接近,但推流式的硝化速率比完全混合式高64%,这是因为推流式更有利于反应速率较快的r-strategist(Nitrosomonas europaea-Nitrosococcus mobilis lineage和Nitrobacter)生存,而完全混合式则更利于反应速率较慢K-strategist(Nitrosospira和Nitrospira)生存。     

Investigation of triclosan fate and toxicity in continuous-flow activated sludge systems

The purpose of this research was to study the fate and toxicity of triclosan (TCS) in activated sludge systems and to investigate the role of biodegradation and sorption on its removal. Two continuous-flow activated sludge systems were used; one system was used as a control, while the other received TCS concentrations equal to 0.5 and 2mgl(-1). At the end of the experiment, 1mgl(-1) TCS was added in the control system to investigate TCS behaviour and effects on non-acclimatized biomass. For all concentrations tested, more than 90% of the added TCS was removed during the activated sludge process. Determination of TCS in the dissolved and particulate phase and calculation of its mass flux revealed that TCS was mainly biodegraded. Activated sludge ability to biodegrade TCS depended on biomass acclimatization and resulted in a mean biodegradation of 97%. Experiments with batch and continuous-flow systems revealed that TCS is rapidly sorbed on the suspended solids and afterwards, direct biodegradation of sorbed TCS is performed. Regarding TCS effects on activated sludge process, addition of 0.5mgl(-1) TCS on non-acclimatized biomass initially deteriorated ammonia removal and nitrification capacity. After acclimatization of biomass, nitrification was fully recovered and further increase of TCS to 2mgl(-1) did not affect the performance of activated sludge system. The effect of TCS on organic substrate removal was minor for concentrations up to 2mgl(-1), indicating that heterotrophic microorganisms are less sensitive to TCS than nitrifiers.     

原位臭氧氧化对活性污泥系统硝化和反硝化作用的影响研究

将厌氧序批式间歇反应器(ASBR)和序批式间歇反应器(SBR)串联组成污泥减量新工艺,着重探讨了对SBR段进行原位臭氧投加时,臭氧氧化作用对系统硝化和反硝化能力的影响,并以不投加作为对照。结果表明,将臭氧原位投加到ASBR—SBR组合工艺的SBR段,臭氧投加量为0.027g(以每克MLSS计),每隔3个周期再次投加、连续运行40d,试验组SBR段臭氧投加当期出水COD去除率为86%,比对照组下降了9百分点,但臭氧氧化细胞内大量有机物进入混合液中,为反硝化作用提供了外加碳源,对污泥反硝化能力的提高起到了一定的促进作用;试验组部分硝化细菌由于臭氧的强氧化作用而失去活性,但是随着剩余污泥量的减少,系统的污泥龄延长,有利于硝化细菌的生长,使得系统的硝化能力基本未受影响;试验组臭氧投加当期SBR段出水NO2--N平均浓度比对照组的高18.9%,但经过3个周期的运行后,其SBR段出水NO2--N平均质量浓度降低至7.57mg/L,基本与对照组持平;试验组臭氧投加当期SBR段出水NO3--N的平均浓度高于对照组,但经过3个周期的运行后,试验组出水NO3--N平均浓度低于对照组;试验组臭氧投加当期SBR段出水TN和对照组的出水TN平均去除率分别为65%和75%,但试验组再经过3个周期的运行后,出水TN平均去除率可以达到72%。可见,原位投加臭氧并未对SBR段的硝化和反硝化能力产生明显的影响。