一体化改性膜生物反应器处理城市污水的效果

利用亲水性的纳米TiO2对强疏水性的聚偏氟乙烯膜进行改性以减缓膜污染,并应用于膜生物反应器(MBR)。原水来自常州市某城市污水厂,经加装改性和未改性膜组件的MBR处理后出水水质均能达到GB 18918—2002中的一级A标准。尽管进水COD浓度不稳定,但两套膜组件对COD的去除率均保持在85%以上,改性膜组件对COD的平均去除率更高,可达94%;对SS的去除率几乎能达到100%;在对TN和TP的去除上,改性膜组件略有优势,但不明显,这是因为N、P的去除主要依靠微生物的降解作用,膜的分离作用不大。在运行一段时间后,两套膜组件的膜通量均有所下降,经在线反冲洗及化学清洗后,通量均有所恢复,分别为73%和78%。对比处理出水水质及抗污染能力,改性膜组件均优于未改性膜组件。     

不同膜通量下MBR处理餐饮废水的研究

分别在5、10、15、20、25 L/(m2.h)5个膜通量下,考察了平板膜生物反应器(MBR)对餐饮废水的处理效果。结果表明,随着膜通量的提高,出水COD和NH3-N浓度稍有升高,但去除率都基本维持在90%以上;同时,MBR对TN、TP、BOD5、DOC、浊度、含油量、SS、UV254等都有很好的去除效果,出水水质完全符合《城市污水再生利用城市杂用水水质》的要求。对比进、出水中DOC的分子质量分布发现,进水中的大分子有机物被降解为小分子有机物。通过测定不同膜通量下混合液的MLSS、SV30、污泥粒径、粘度等指标,发现MLSS和SV30与粘度之间有很好的线性关系。在运行结束时进行阻力分布测试,发现随着膜通量的增大,内部阻力比例逐渐增大,而滤饼层阻力和浓差极化阻力的比例都逐渐下降。     

投加粉末炭对SMBR过滤性能的影响

在相同的进水和运行务件下，考察和比较了生物活性炭一膜生物反应体系(BPAc—SMBR)与常规的活性污泥一膜生物反应体系(AS—SMBR)的膜过滤特性，并就粉末活性炭(PAC)对通量改善的相关机理进行了探讨。结果表明，添加1．2g／L的PAC可明显改善SMBR的过滤性能。与AS—SMBR相比。BPAC—SMBR的临界通量可提高32％；相同恒通量下的长期运行结果也表明BPAC-SMBR透膜压力的升高更为缓慢，其稳定运行周期可达到AS—SMBR的1．8倍；BPAC-SMBR的膜过滤总阻力比AS—SMBR的低约44％，其差别主要来自于滤饼阻力的减少。此外。还分析了混合液粘度、粒径分布等影响因素。     

MBR膜丝表面生物膜对出水水质的稳定作用

在膜生物反应器（MBR）发生溶解性微生物产物（SMP）积累的情况下,对新膜与旧膜的出水水质进行了比较.结果表明,旧膜具有比新膜更为稳定和良好的出水水质,其出水平均TOC浓度为12.9 mg/L,低于新膜出水的36.8 mg/L,表明膜丝表面的生物膜强化了系统对SMP的截留能力.MBR上清液中分子质量＞10 ku的大分子物质与分子质量＜3 ku的小分子物质占有相当大的比例,旧膜对所有分子质量物质的截留效果均优于新膜.旧膜经清洗后,其出水的TOC浓度随着膜比通量的下降而降低.     

改性微滤膜深度处理城市污水的研究

采用改性SiO2纳米粒子对微滤膜进行改性,考察了改性微滤膜的分离特性及对城市污水的深度处理效果.结果表明,改性后的微滤膜表面的亲水性明显提高,膜的传质系数增大,膜阻力系数减小,膜的耐污性能大大增强;采用改性微滤膜处理城市污水厂的二级出水,膜出水水质可满足<城市污水再生利用城市杂用水水质>(GB/T 18920--2002)的要求,且连续运行10 h后,膜通量仍可稳定在150 L/(m2·h)以上;适量增大过膜压力可提高膜通量和水回收率,错流过滤方式比死端过滤方式的膜通量高,内压进水方式比外压进水方式的膜通量高.     

投加颗粒活性炭对膜生物反应器过滤特性的影响

膜污染是制约膜技术应用的重要因素。向膜生物反应器(MBR)中投加颗粒活性炭(GAC),通过分析MBR系统中膜通量、过滤阻力等的变化,考察投加GAC对MBR系统过滤特性的影响。结果表明,运行30d后,未投加和投加GAC的MBR系统的膜通量分别降至初始的31.3%和91.7%;未投加GAC系统的总过滤阻力和极化阻力分别为投加GAC系统的5.8和19.4倍,其污泥的多糖和蛋白质含量为投加GAC系统的近2倍,而其胶体物质和溶解性物质浓度分别为投加GAC系统的3.2和2.2倍。由此表明,投加GAC可大大减缓膜污染,延长膜的过滤周期。     

浅谈膜生物反应器(MBR)处理城市污水回用

膜生物反应器（MBR）处理城市污水回用具有广阔的应用前景。MBR具有较强的抗冲击负荷能力，活性污泥对污染物的去除起主要作用，膜分离对维持稳定的出水起重要作用。膜生物反应器出水稳定，水质良好，优于生活杂用水水质标准。     

PAC/MBR处理微污染地表水的中试研究

采用投加粉末活性炭(PAC)的膜生物反应器(MBR)复合工艺——PAC/MBR处理微污染地表水,考察了对浊度、CODMn和氨氮的去除效果。膜生物反应器的有效容积为4m3,采用聚偏氟乙烯平板膜,膜孔径为0.09～0.12μm,总膜面积为85.2m2;MBR的进水流量为1200L/h,一次性投加PAC为1g/L,气水比为5∶1;采用恒压操作、间歇抽吸方式出水,操作压力为0.1MPa,抽停比为8min/2min。中试结果表明,该工艺对沉淀池出水中浊度、CODMn和氨氮的平均去除率分别为98%、33%和53%,能抵抗水质和水温变化的冲击,有效保障出水水质。在PAC/MBR系统中,PAC吸附、生物降解和膜截留作用在去除不同分子质量有机物的过程中具有较好的互补性。投加PAC有助于在膜表面形成稳定的生物活性炭动态膜,保证了恒定的出水流量。     

颗粒活性炭干扰膜表面滤饼层形成的研究

向膜生物反应器（MBR）中投加颗粒活性炭（GAC）以干扰膜面滤饼层的形成,减轻膜污染与膜堵塞.结果表明,向MBR中投加粒径为40～60目的GAC（投量为1 g/L）,反应器运行21 d后,膜出水流量为初始时的52.9%,比对照试验的（30.8%）高22.1%;膜组件外层膜丝表面无滤饼层,内层膜丝间有滤饼层形成,部分GAC被吸附到滤饼层中从而增大了其孔隙率,提高了其透水率;GAC使滤饼层结构变得疏松而易于清洗,水力清洗后,在抽吸压力为0.02 MPa下膜清水通量可恢复到新膜的53.5%,比对照试验的高16%.     

A/O-MBR工艺处理城市污水的研究

针对水资源短缺、水污染严重和用水量增加的状况,进行了膜生物反应器（MBR）处理城市污水的中试,考察了出水回用奥运公园的可行性.试验结果表明,系统出水SS、COD、氨氮、Fe、Mn的浓度分别为0、16.3、0.65、0.2、0.033 mg/L,去除率分别达到100%、94.5%、98.3%、99%和92.3%;出水浊度和细菌数分别为0.06 NTU、4 CFU/mL,去除率为99.7%和6-lg,出水水质优于城市杂用水水质标准（GB/T 18920-2002）.系统运行稳定,有较强的抗冲击负荷能力.膜过滤压差的变化和膜的清洗试验表明,DO和泥饼层增厚压密是影响膜污染的重要因素.     

改进型MBR处理生活污水及减缓膜污染的效能研究

通过长期运行试验,考察了改进型膜生物反应器(MBR)对污染物的去除效果和减缓膜污染的能力.结果表明,改进型NBR对COD和NH3-N的去除效果与传统MBR的类似,出水COD和NH3-N分别低于50 mg/L和5 mg/L;改进型MBR对TN的去除效果优于传统MBR,且具有更好的减缓膜污染的能力,在近90d的连续运行过程中,改进型MBR的膜组件仅需清洗2次.而传统MBR的膜组件则清洗了5次.     

优势菌强化膜生物反应器处理制药废水研究

利用膜生物反应器对泥水能高效分离的特点,将优势菌技术与膜生物反应器结合处理避孕药生产废水,并在反应条件相同的情况下,与普通膜生物反应器的处理效果进行了比较.试验结果表明,向膜生物反应器中投加优势菌后,可实现系统的稳定运行,对COD的去除率90%,出水水质达到了北京市地方标准--<水污染物排放标准>(DB 11/307-2005);同时,优势菌的投加还增强了异养微生物的活性,提高了对NH3-N的去除效率.     

改良型氧化沟扩容改造AAO-MBR工艺工程设计

针对四川省某县城市污水处理厂存在的处理能力不足、厂区用地紧张、出水水质亟需提标等问题,扩容改造工程中将现状改良型氧化沟改造为AAO生化池,现状二沉池改造为MBR膜池,并同时新建一座MBR膜综合车间与之配套,形成新的AAO-MBR深度处理工艺。工程完成后,污水处理能力由3. 0×10~4m^3/d提升至3. 5×10~4m^3/d,实际运行出水COD≤25. 0 mg/L、NH_3-N≤1. 5 mg/L、TN≤8. 0 mg/L,出水水质满足《四川省岷江、沱江流域水污染物排放标准》(DB 51/2311—2016)相关标准。工程总投资为3 589. 2万元,MBR膜系统运行成本为0. 439元/m^3,结合整体厂区运行工况,总处理成本稳定在1. 15~1. 30元/m^3之间。     

Biological black water treatment combined with membrane separation

Separate treatment of black (toilet) water offers the possibility to recover energy and nutrients. In this study three combinations of biological treatment and membrane filtration were compared for their biological and membrane performance and nutrient conservation: a UASB followed by effluent membrane filtration, an anaerobic MBR and an aerobic MBR. Methane production in the anaerobic systems was lower than expected. Sludge production was highest in the aerobic MBR, followed by the anaerobic MBR and the UASB-membrane system. The level of nutrient conservation in the effluent was high in all three treatment systems, which is beneficial for their recovery from the effluent. Membrane treatment guaranteed an effluent which is free of suspended and colloidal matter. However, the concentration of soluble COD in the effluent still was relatively high and this may seriously hamper subsequent nutrient recovery by physical-chemical processes. The membrane filtration behaviour of the three systems was very different, and seemed to be dominated by the concentration of colloidals in the membrane feed. In general, membrane fouling was the lowest in the aerobic MBR, followed by the membranes used for UASB effluent filtration and the anaerobic MBR.     

膜生物反应器在污水深度处理中的技术研究

试验研究了以膜生物反应器(MBR)为核心的单元式再生水处理装置(处理能力为30m3/d)在设置成A/O型MBR和A2/O型MBR两种工艺组合和不同运行条件下(如安装BS填料、投加PAC、改变原水条件和增减膜组件数量等)对城市污水的深度处理效果。试验结果表明单元式再生水处理装置具有较高的污泥浓度(MLSS=10000～12000mg/L)和较强的抗冲击负荷(温度、水质变化等)能力。在不同工况下CODcr、BOD5、NH3-N、TN、SS、浊度、色度和粪大肠菌群数等指标均达到或优于国家一级A标准。优化的A2/O型MBR工艺的各项出水指标达到或优于国家一级A标准。BS填料可明显提高生物脱氮效率。     

立式A/O-MBR处理生活污水的试验研究

建立了立式A/O-MBR系统,该系统在A段与O段体积比为0.7时,TN去除效果较为理想.运行期间,对COD、NH3-N、TN的去除效率均较高.而立式A/O-MBR所需占地面积小于其他工艺,具备将其投入工程应用的潜质.试验中对比了由尼龙筛网形成的DMBR与MBR在运行状况与出水水质上的差异性,结果表明:DMBR一定程度上能够有效克服MBR成本高、易污染等缺点,且出水水质良好.     

Membrane bioreactor for the drinking water treatment of polluted surface water supplies

A laboratory membrane bioreactor (MBR) using a submerged polyethylene hollow-fibre membrane module with a pore size of 0.4 microm and a total surface area of 0.2 m2 was used for treating a raw water supply slightly polluted by domestic sewage. The feeding influent had a total organic carbon (TOC) level of 3-5 mg/L and an ammonia nitrogen (NH(3)-N) concentration of 3-4 mg/L. The MBR ran continuously for more than 500 days, with a hydraulic retention time (HRT) as short as 1h or less. Sufficient organic degradation and complete nitrification were achieved in the MBR effluent, which normally had a TOC of less than 2 mg/L and a NH(3)-N of lower than 0.2 mg/L. The process was also highly effective for eliminating conventional water impurities, as demonstrated by decreases in turbidity from 4.50+/-1.11 to 0.08+/-0.03 NTU, in total coliforms from 10(5)/mL to less than 5/mL and in UV(254) absorbance from 0.098+/-0.019 to 0.036+/-0.007 cm(-1). With the MBR treatment, the 3-day trihalomethane formation potential (THMFP) was significantly reduced from 239.5+/-43.8 to 60.4+/-23.1 microg/L. The initial chlorine demand for disinfection decreased from 22.3+/-5.1 to 0.5+/-0. 1mg/L. The biostability of the effluent improved considerably as the assimilable organic carbon (AOC) decreased from 134.5+/-52.7 to 25.3+/-19.9 microg/L. All of these water quality parameters show the superior quality of the MBR-treated water, which was comparable to or even better than the local tap water. Molecular size distribution analysis and the hydrophobic characterisation of the MBR effluent, in comparison to the filtered liquor from the bioreactor, suggest that the MBR had an enhanced filtration mechanism. A sludge layer on the membrane surface could have functioned as an additional barrier to the passage of typical THM precursors, such as large organic molecules and hydrophobic compounds. These results indicate that the MBR with a short HRT could be developed as an effective biological water treatment process to address the urgent need of many developing countries that are plagued by the serious contamination of surface water resources.     

影响MBR处理效果及膜通量的因素研究

采用处理规模为10m^3/d的厌氧／好氧膜生物反应器（A／O MBR）处理毛纺印染废水，试验结果表明：当原子COD、BOD5、色度、浊度分别为256．5mg/L,94.8mg/L,64倍，45．65NTU时，相应的出水指标分别为20．2mg/L,1.6mg/L,25倍，0．51NTU，其水质达到《生活杂用水水质标准》（CJ25．1－89）；溶解氧是影响处理效果的一个关键因素；随着运行时间的延长、膜污染的增加，温度对膜通量的影响降低；膜面流速较高时，污泥浓度对膜通量没有显著影响。     

Cyclophosphamide removal from water by nanofiltration and reverse osmosis membrane

The rejection of cyclophosphamide (CP) by nanofiltration (NF) and reverse osmosis (RO) membranes from ultrapure (Milli-Q) water and membrane bioreactor (MBR) effluent was investigated. Lyophilization-extraction and detection methods were first developed for CP analysis in different water matrices. Experimental results showed that the RO membrane provided excellent rejection (>90%) under all operating conditions. Conversely, efficiency of CP rejection by NF membrane was poor: in the range of 20-40% from Milli-Q water and around 60% from MBR effluent. Trans-membrane pressure, initial CP concentration and ionic strength of the feed solution had almost no effect on CP retention by NF. On the other hand, the water matrix proved to have a great influence: CP rejection rate by NF was clearly enhanced when MBR effluent was used as the background solution. Membrane fouling and interactions between the CP and water matrix appeared to contribute to the higher rejection of CP.