茶多酚冲洗废水处理工艺的研究

采用SBR反应器、活性炭床,通过对CODCr、色度、pH等指标的监测和数据分析、废水颜色的观察,研究了多种方法及其组合工艺对茶多酚冲洗废水的处理效果.试验结果表明:采用絮凝沉淀-两级好氧生物处理-活性炭床组合工艺处理茶多酚冲洗废水是可行的.CODCr和色度的去除率分别大于97%和95%,处理后出水CODCr＜100mg/L,出水色度＜50倍.     

膜生物反应器的污泥特性和膜污染研究

对中试规模的缺氧—好氧—膜生物反应器(A/O—MBR)处理城市污水进行研究,并对好氧池内活性污泥的特性和膜污染后期的影响因素进行了分析。试验结果表明:污泥浓度(MLSS)对CODCr、氨氮等各指标的处理效果均有影响。与传统活性污泥工艺相比,膜生物反应器污泥负荷小、表观产泥率低。     

影响CASS工艺除磷效果的运行参数研究

CASS工艺由于其优良的除磷脱氮功能而得到了广泛的应用。以正交试验的方法,研究曝气比、污泥回流比、SRT和MLSS4个运行参数对CASS工艺除磷效果的影响。通过SPSS统计软件进行方差分析,并结合已有的研究成果,分析了曝气比、污泥回流比、SRT和MLSS 4个运行参数对除磷效果的影响顺序,以及在不同水平上对除磷效果的影响,总结出最佳的试验组合为曝气比(0.5)、污泥回流比(0.2)、SRT(10d)、MLSS(2000mg/L)。     

江山化工废水处理站一期工程调试

通过对江山化工废水处理站一期工程3个多月的调试,表明复合厌氧(HAR)-好氧工艺处理高浓度有机废水在常温下调试100 d左右可以顺利运行,甚至在进水量达625 m3/d,容积负荷达3.26 kgCODCr/(m3·d)条件下,HAR对CODCr的去除率仍能保持在40%左右,系统CODCr去除率可达90%以上.好氧硝化效率为75.2%,出水氨氮、CODCr分别为37.2 mg/L、365.57 mg/L,达到设计要求.     

两级SBR工艺处理顺酐和富马酸废水的研究

采用两级SBR工艺对顺酐和富马酸生产废水进行了处理,考察了污泥浓度、反应时间对处理效果的影响以及反应过程中pH的变化规律.结果表明,MLSS为5.9 g/L比MLSS为11.2 g/L的处理效果好.当进水CODCr为6 300 mg/L,BOD5为4 715 mg/L,NH3-N为369 mg/L,试验在充水1 h、沉淀2 h、闲置3 h、非限量曝气、一级SBR(MLSS为5.9 g/L)反应时间10 h、二级SBR (MLSS为4.1 g/L)反应18 h条件下时,出水中CODCr为648 mg/L、去除率为89.7%,BOD5为85 mg/L、去除率为98.2%,NH3-N为20 mg/L、去除率为94.6%.pH随CODCr的降低而升高,当CODCr的降低幅度趋缓时,pH的升高幅度也随着趋缓.     

水解酸化-好氧生物工艺处理制浆造纸综合废水

介绍了一种以水解酸化-好氧生物工艺为核心的处理能力2万m3/d制浆造纸综合废水的工艺,对处理系统的启动和调试过程进行了总结,重点分析了污泥的培养和驯化、污泥负荷、调试中混凝剂的选择及浓度等因素对系统运行的影响.经过一个多月的调试,系统达到稳定,出水CODCr小于400 mg/L,SS小于80 mg/L,去除率均大于80%,达到了《造纸工业水污染物排放标准》(GB 3544-2001),表明该工艺设计合理、运行稳定可靠,具有处理效率高、投资省和运行费用少的特点.     

水解酸化-好氧移动床膜生物反应器处理高浓度有机废水的试验研究

好氧移动床膜生物反应器(M-CMCBR)是生物膜法与微滤膜相结合的一种新型反应器。采用水解酸化-好氧移动床膜生物反应器处理高浓度有机废水和含酚废水。试验结果表明:此工艺可以提高难降解有机废水的可生化性,继而得到较好的出水水质。进水CODCr为3000～5000mg/L时,最终膜出水CODCr为30～90mg/L,总去除率为98.5%～99.5%。     

小型化A/O工艺处理肉类加工废水

某肉类加工厂废水采用A/O工艺处理,运行结果显示,系统进水CODCr为1 300～1 500 mg/L、TKN为120～150 mg/L,出水CODCr为20～40 mg/L,NH3-N<0.2 mg/L,TN去除率为85%～90%,且系统保持高生物量(MLSS达6～6.2 g/L)与低污泥负荷[(0.075 gCODCr/(gSS·d))].     

改变SBR工艺运行方式对污染物去除效果试验研究

SBR法以其运行方式灵活的特点可以实现对不同污染物去除的控制,本试验基于此特点,通过改变SBR工艺的运行方式,考察不同运行条件下CODCr、NH3-N、TP的去除率,从中确定最佳运行参数.在最佳运行参数下,稳定运行8个周期,出水CODCr、NH3-N、TP均能达到生活杂用水标准.     

生物助剂在制浆废水处理中的应用研究

对某制浆厂生产废水处理系统投加由多种酵素混合而成的生物助剂前后的运行效果进行详细分析.结果表明:在工艺运行参数不变的条件下,使用生物助剂能够提高生物处理系统的生物活性,增加活性生物量,使生物处理系统对CODCr、SS、色度去除率分别提高16%、17%、27%,降低了化学处理单元药剂使用量,增强了生物处理系统的耐冲击负荷能力,降低了水处理成本,对生物助剂在制浆废水处理中应用具有重要的推动作用.     

CASS工艺生物脱氮除磷效果分析

对CASS工艺脱氮除磷效果进行了试验研究,重点研究了温度和回流比对脱氮效果的影响,曝气量对除磷效果的影响。研究结果表明,水温在30℃时系统脱氮效果最好,此时NH3-N去除率在80%左右,TN去除率在70%左右;污泥回流比为25%、50%、100%和200%时,TN去除率分别为50%、58%、62%和70%,增加回流比可以提高脱氮效率;好氧区DO维持在2mg/L和4 mg/L时,TP去除率分别为82%和37%。     

厌氧生物滤池+生物接触氧化组合工艺处理地表微污染水技术研究

通对通惠河通州段地表微污染水进行水质改善处理技术研究,确定采用厌氧生物滤池+生物接触氧化的组合工艺进行处理,通过试验确定工艺的最佳运行参数为厌氧生物滤池HRT=15 h,生物接触氧化池气水比10,水力停留时间为4 h,回流比为100%。出水中氨氮浓度为0.34 mg/L,总氮浓度为3.2 mg/L,总磷浓度为0.38 mg/L,CODCr浓度为34 mg/L,出水各指标完全满足《地表水环境质量标准(GB3838-2002)》中Ⅴ类水体质量标准,其中总氮浓度远低于课题研究目标的15 mg/L。     

Monitoring the variations of the oxygen transfer rate in a full scale membrane bioreactor using daily mass balances

Oxygen transfer in biological wastewater treatment processes with high sludge concentration, such as membrane bioreactor (MBR), is an important issue. The variation of alpha-factor versus mixed liquor suspended solids (MLSS) concentration was investigated in a full scale MBR plant under process conditions, using mass balances. Exhaustive data from the Supervisory Control And Data Acquisition (SCADA) and from additional online sensors (COD, DO, MLSS) were used to calculate the daily oxygen consumption (OC) using a non-steady state mass balance for COD and total N on a 24-h basis. To close the oxygen balance, OC has to match the total oxygen transfer rate (OTRtot) of the system, which is provided by fine bubble (FB) diffusers in the aeration tank and coarse bubbles (CB) in separate membrane tanks. First assessing OTR(CB) then closing the balance OC = OTRtot allowed to calculate OTR(FB) and to fit an exponential relationship between OTR(FB) and MLSS. A comparison of the alpha-factor obtained by this balance method and by direct measurements with the off-gas method on the same plant is presented and discussed.     

Correlation between membrane fouling and soluble/colloidal organic substances in membrane bioreactors for municipal wastewater treatment.

Two similar membrane bioreactors of 2 m3 each were operated in parallel over two years under the same operational conditions, fed with the same municipal wastewater. The only process and operational difference between both pilot plants was the position of the denitrification zone (pre-denitrification in pilot 1 and post-denitrification in pilot 2). Despite parallel operation, the two MBRs exhibited different fouling rates and decreases in permeability. These differences could not be accounted for by MLSS concentrations, loading rates, or filtration flux. In a one-year investigation, soluble and colloidal organic material in the activated sludge of both MBR was regularly analysed by spectrophotometric and Size Exclusion Chromatography (SEC) methods. The larger organic molecules present in the sludge water phase (i.e. polysaccharides, proteins and organic colloids) originating from microbial activity (extracellular polymeric substances) were found to impact on the fouling and to explain the difference in membrane performance between the two MBR units. In both pilot plants, a linear relationship could be clearly demonstrated between the fouling rate of the membrane and the concentration of polysaccharides in the sludge water phase during a 5 month operational period at an SRT of 8 days.     

Pilot study on municipal wastewater treatment by a modified submerged membrane bioreactor.

A pilot-scale modified submerged membrane bioreactor (SMBR) with the capacity of 18.1 m3d(-1) was developed on the basis of the principle of air-lift internal-loop reactor. Economical aeration intensity of the SMBR was determined as 96 m3m(-2)h(-1) according to hydrodynamic investigation. Corresponding economical air-flow rate was selected as the working air-flow rate in the long-term run. Under economical aeration intensity, the critical flux zone of the modified SMBR was as high as 30-35 Lm(-2)h(-1) when MLSS was less than 13 gL(-1). Therefore, a sub-critical flux of 30 Lm(-2)h(-1) was selected as the working membrane flux in the long-term run. Membrane fouling was effectively controlled by sub-critical flux operation and periodic on-line chemical cleaning in the long-term run. When the average influent CODCr, NH3-N and turbidity were 310 and 44.3 mgL(-1) and 161 NTU, respectively, the average permeate were 38.5 and 19.5 mgL(-1) and 0.96 NTU under hydraulic retention time (HRT) was only 2.8 h. Corresponding removal was 86, 58.2 and 99.4%. DO deficiency caused by high MLSS was demonstrated as the main reason for low NH3-N removal.     

Evaluation of the importance of various operating and sludge property parameters to the fouling of membrane bioreactors

A single-fibre microfiltration system was employed to investigate the importance of various operating and sludge property parameters to the membrane fouling during sludge filtration. The sludge was obtained from a submerged membrane bioreactor (SMBR). A series of comparative and correlative filtration and fouling tests were conducted on the influence of the operating variables, sludge properties and the liquid-phase organic substances on the membrane fouling development. The test results were analysed statistically with Pearson's correlation coefficients and the stepwise multivariable linear regression. According to the statistical evaluation, the membrane fouling rate has a positive correlation with the biopolymer cluster (BPC) concentration, sludge concentration (mixed liquor suspended solids, MLSS), filtration flux and viscosity, a negative correlation with the cross-flow velocity, and a weak correlation with the extracellular polymeric substances and soluble microbial products. BPC appear to be the most important factor to membrane fouling development during the sludge filtration, followed by the filtration flux and MLSS concentration. The cross-flow rate also is important to the fouling control. It is argued that, during membrane filtration of SMBR sludge, BPC interact with sludge flocs at the membrane surface to facilitate the deposition of the sludge cake layer, leading to serious membrane fouling.     

Performance of a combined eco-system of ponds and constructed wetlands for wastewater reclamation and reuse.

An on-site study on the operational performance of a combined eco-system of ponds and SF constructed wetland for municipal wastewater treatment and reclamation/reuse in Donging City, Shandong, China was carried out from January 2001 through October 2003. The removal efficiencies for various main parameters were: TSS 84.8 +/- 7.3%, BOD5 87.2 +/- 5.3%, CODCr 70.2 +/- 18.6%, TP 52.3 +/- 23.1%, and NH(3)-N 54.8 +/- 23.9% with effluent concentration of TSS 9.12 +/- 5.12 mg/l, BOD5 6.44 +/- 4.58 mg/l, CODCr, 42.8 +/- 6.7 mg/l, TP 0.94 +/- 0.27 mg/l and NH(3)-N 7.95 +/- 2.36 mg/l. In addition, the removal efficiencies for faecal coliforms and total bacteria were > 99.97% and > 99.998% respectively, which well meet Chinese National standards for effluent quality of municipal wastewater treatment plants. The composition of TSS was closely related to CODCr and BOD5 variations, and nitrification-denitrification is the major mechanism of nitrogen removal both in ponds and in wetlands. In addition, sedimentation also played an important role in the removal of TSS, nitrogen, phosphorus and BOD5. The removal efficiencies of various parameters, the number of species and biomass of biological community in the system increased gradually with the ecological maturation.     

催化湿式氧化法处理高浓度对氯苯基异氰酸酯生产废水的研究

在固定床鼓泡式反应器连续反应装置上对对氯苯基异氰酸酯生产过程中产生的高浓度实际废水进行催化湿式氧化处理。实验表明:制备的复合负载型催化剂CuO-ZrO2-CeO2/TiO2在处理该废水时具有较好的催化活性。通过对反应温度、反应压力、反应空速、气液比和进水pH等工艺条件的考察,得出最佳的工艺条件为:反应温度T=240℃,反应压力P=6.5MPa,空速=2.0 h-1,V(气)∶V(水)=230∶1,进水pH=8,在此条件下CODCr去除率达到96.9%。     

芬顿法深度处理造纸废水

利用芬顿(Fenton)法对造纸废水生化出水进行深度处理,考察了废水pH值、反应时间、FeSO4投加量和H2O2投加量对废水中色度和CODC r去除率的影响。结果表明:在pH值为5.00、FeSO4投量为400 mg/L、30%H2O2投量为200 mg/L,反应时间为30 m in,出水CODC r可降至60 mg/L以下,色度的去除率可达到74%,可以满足更为严格的造纸废水排放标准,为进一步的工程设计提供依据。