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。     

竹炭曝气生物滤池的挂膜启动研究

研究了上流式竹炭曝气生物滤池（UBAF）处理生活污水的启动规律。探讨了挂膜过程中曝气生物滤池与竹炭空白试验中COD、BODs以及NH3-N随时间的变化规律。结果表明：历时21d,COD与BOD5的质量浓度可以降至80．76mg／L和31．97mg／L以下,去除率均达到80％以上;NH3-N的出水质量浓度在14．79mg／L以下,去除率也达到70％以上。据此得出曝气生物滤池挂膜启动成功。     

—体化间歇曝气多级生物膜反应器处理低温、低浓污水

采用新型一体化间歇曝气多级生物膜反应器处理低浓度小城镇污水，重点考察了冬季低温（5～8℃）对反应器处理效能的影响，以及采用分级间歇曝气方式能否解决连续流生物膜反应器除磷效能低的问题。试验结果表明：在水温为5～8℃、有机负荷为0．5kgCOD／（m^3·d）、氮负荷为0．12kgN／（m^3·d）、DO为6．0mg／L、HRT为6．0h、挂膜密度为30％，以及第一、二级生物膜反应区的停曝与曝气时间比均为1．0h／2．0h的条件下，处理平均COD为120mg／L、TN为30mg／L、NH4^＋-N为27mg／L、PO4^3--P为1．9mg／L的低浓度城镇污水，可使出水COD≤35mg／L，NH4^＋-N≤3．3mg／L，TN≤19mg／L，PO4^3--P≤0．8mg／L，达到了《城镇污水处理厂污染物排放标准》（GB 18918-2002）的一级B标准。     

DAT-IAT改进工艺对生活污水中氨氮的去除

以需氧池-间歇曝气池（DAT-IAT）工艺为基础，在其后设置一生物接触氧化反应器，考察了该组合工艺对生活污水中氨氮的去除效果。结果表明，在IAT池以曝气2h、沉淀1h、出水1h的工况运行及生物接触氧化反应器的HRT为3h的条件下，系统对氨氮的平均去除率为81．1％，出水氨氮平均浓度为7．0mg／L，满足《城市污水再生利用城市杂用水水质》（GB／T 18920-2002）的要求。系统对氨氮的去除率随着进水COD浓度的提高而下降，当进水COD为815．3mg／L时，出水氨氮浓度仍可满足GB／T 18920-2002的要求；随着进水氨氮浓度的提高，系统对氨氮的去除率先略有上升后明显下降，为保证出水氨氮浓度达到回用标准，应将进水氨氮浓度控制在50mg／L以下；系统适宜的pH值范围为7～8，pH值过高或过低都会造成系统对氨氮去除率的显著下降。     

复合MBR处理厕所污水与回用的试验研究

针对我国城市厕所污水处理与回用技术的迫切需求及传统膜生物反应器（MBR）能耗高的缺点，开发了一种复合MBR装置，它以气升为动力来完成SBR单元和膜单元间混合液的水力循环，并依靠SBR的液位水头实现膜单元的无动力出水。在进水COD为（330±33）mg／L、NH3-N为（12．1±1．2）mg／L、TN为（13．5±1．3）mg／L、TP为（1．9±0．2）mg／L、SS为（135±5．3）mg／L的条件下，对COD、NH3-N、TN、TP和SS的去除率分别为92．4％、95％、50．5％、96．4％和100％，出水水质达到了《城市污水再生利用城市杂用水水质》（GB／T18920-2002）标准中的冲厕水质要求。     

三维电极/电Fenton法去除垃圾渗滤液中的COD

考察了三维电极／电Fenton法对垃圾渗滤液中COD的去除效果及其影响因素,并探讨了COD的降解动力学。结果表明,在涂膜炭填充率为20％、炭水比为0．5、极板间距为10cm、电流密度为57．1mA／cm^2、曝气量为0．2m^3／h、Fe^2＋浓度为1mmoL／L、pH值为4的最佳条件下,电解180min后,对COD的去除率为80．8％,明显高于电Fenton法（58．83％）和三维电极法（69．64％）;三维电杉电Fenton法对垃圾渗滤液中COD的降解符合拟三级反应动力学方程,当原水COD为1634mg／L时,动力学常数k=2．197×10^-8L^2／（mg^2·min）。     

低DO下曝气方式对分段进水脱氮工艺的影响

采用分段进水生物脱氮工艺处理小区生活污水,考察了在低DO条件下,不同曝气方式对硝化率及污泥沉降性能的影响。结果表明,在曝气量为0．27m^3／h、MLSS平均为2700mg／L左右、好氧区的DO为0．26～2．5mg／L的条件下,当进水氨氮为44～55mg／L时,对氨氮的去除率保持在95％以上,对COD的去除率〉90％;当控制好氧区第1、2格室的DO分别为0．5～0．7和1．0～1．2mg／L时,系统的硝化率维持在90％以上,出水中的氨氮〈2mg／L;在恒定曝气量下,向进水中投加有机碳源,当水质改变较快时,容易引起丝状菌污泥膨胀,但通过恒DO曝气控制,可使污泥的沉降性能得到改善。     

MBR和UF深度处理石化废水的比较研究

为给某石化企业的反渗透（RO）系统提供水质良好且稳定的进水，分别采用膜生物反应器（MBR）和超滤（UF）工艺对该厂二沉池出水进行了深度处理试验，考察了进、出水的浊度及COD、SDI等指标。结果表明：UF系统的出水浊度平均为0．18NTU，COD平均为22．1mg／L，SDI平均为2．50；MBR系统的出水浊度平均为0．14NTU，COD平均为20．1mg／L，SDI平均为2．22。MBR的出水水质比UF更稳定，且具有较强的耐冲击负荷能力。     

UASB/水解酸化/曝气生物滤池处理高浓度聚酯废水

介绍了UASB／水解酸化／曝气生物滤池工艺在聚酯废水处理中的应用，并进行了工艺参数的选择和运行效果的分析。结果证明，当进水COD、BOD5浓度分别为（1—1．2）×10^4mg／L和3450—4200mg／L时，处理出水COD≤150mg／L，BOD5≤30mg／L，能够达到《污水综合排放标准》（GB8978--1996）的二级排放标准。     

CAST工艺处理城市污水的强化脱氮研究

介绍了镇江征润州污水处理厂CAST工艺的运行情况，结合该厂实际运行状况开展了强化脱氮效果的生产性试验研究。结果表明，该工艺对COD、SS和TP的去除率均能维持在80％以上，但对氨氮的去除效果较差；在该厂运行模式下，控制进水／曝气前30min的DO〈0．5mg／L、进水／曝气后30min的DO浓度在1．0-3．0mg／L、纯曝气DO浓度在2．0-3．0mg／L，可以实现同步硝化反硝化和硝化／反硝化作用下的共同脱氮，使脱氮效率提高了57％左右；在控制进水／曝气后DO〈0．5mg／L、纯曝气DO浓度在1．0-3．0mg／L的条件下，可以实现同步硝化反硝化作用下的脱氮，但较难实现理想的脱氮效果。     

A/O除磷工艺丝状菌污泥膨胀的研究

丝状菌污泥膨胀是影响活性污泥法高效、稳定运行的重要因素。采用A/O生物除磷工艺中试装置处理实际生活污水,分析了污泥膨胀发生的原因及恢复系统性能的方法。结果显示,长期曝气不均匀是导致丝状菌污泥膨胀的重要原因,通过调控系统运行参数可以有效控制由低DO值或者高负荷引起的丝状菌污泥膨胀。当发生污泥膨胀后,首先降低负荷至0.45 kgCOD/(kgMLSS.d),调节回流比为83%,同时控制好氧池各段的DO分别为1.5、1.0、1.0 mg/L以淘汰丝状菌,在SVI值降至200 mL/g以下后继续降低回流比至53%,同时降低曝气量以形成1.0、0.5、0.5 mg/L的DO浓度梯度。采取上述调控措施后,SVI值由569.8 mL/g降至150 mL/g以下,污泥性状得以恢复;同时出水COD和TP分别在50、0.5 mg/L以下,去除率分别约为85%、95%。     

Influence of mixed liquor recycle ratio and dissolved oxygen on performance of pre-denitrification submerged membrane bioreactors

The conflicting influence of mixed liquor recycle ratio and dissolved oxygen on nitrogen removal and membrane fouling of a pre-denitrification submerged MBR was investigated in this study. It was found that a high aeration rate of 10 L air/min was able to minimize membrane fouling as compared with lower aeration rates of 5 and 2.5L air/min in this study. Faster fouling at lower aeration rate was due to the decrease in cross-flow velocity across the membrane surface. However, high DO concentration (average of 5.1+/-0.5mg O2/L) present in the recycle mixed liquor at an aeration rate of 10 L air/min deteriorated the TN removal efficiency when operating at a recycle ratio of more than 3. A lower aeration rate of 5L air/min, resulting in an average DO concentration of 3.4+/-0.7 mg O2/L in the recycle mixed liquor, led to an improvement in TN removal efficiency: 63%, 80%, 84% and 89% for mixed liquor recycle ratio of 1, 3, 5 and 10, respectively. Further decrease in aeration rate to 2.5L air/min, resulting in an average DO concentration of 1.9+/-0.8 mg O2/L, did not improve the TN removal efficiency. Using a newly developed simplified nitrification-denitrification model, it was calculated that the COD/NO3(-)-N required for denitrification at 10 L air/min aeration rate was higher than those associated with 5 and 2.5L air/min aeration rates. The model also revealed that denitrification at an aeration rate of 10 L air/min was limited by COD concentration present in the wastewater when operating at a mixed liquor recycle ratio of 3 and higher.     

中空纤维膜无泡曝气氧传质性能试验研究

为探究中空纤维膜无泡曝气技术水体充氧性能,使用聚四氟乙烯(PTFE)和聚丙烯(PP)两种材质的中空纤维膜组件,分别在曝气压强为2、4、6 kPa,曝气流量为18、36、54 L/h条件下进行清水曝气测试,并对两种中空纤维膜的氧传质系数、氧传质速率以及曝气效率等进行分析。结果表明,PTFE和PP两种中空纤维膜组件均能实现无泡曝气,且PP中空纤维膜组件的充氧效果相比PTFE组件要好;当曝气压强为4 kPa、曝气流量为36 L/h时,PTFE和PP膜组件的氧传质速率分别为0.326、0.550 g/(m^2·h)。中空纤维膜无泡曝气技术具有操作压力小、氧传质速率高等特点,充氧效果优于传统曝气。     

射流曝气MBR工艺处理城市污水的研究

传统膜生物反应器(MBR)的能耗较大、运行费用较高,为此开发了射流曝气MBR工艺。采用其处理某开发区污水,在进水COD为60～300 mg/L、氨氮为3～30 mg/L、总磷为0.8～5 mg/L、水力停留时间为2 h的条件下,出水COD、氨氮、总磷的平均值分别为25、1.27、1.66 mg/L,平均去除率分别为84%、93%、46%。反应器采用射流曝气方式,提高了氧的转移效率,大幅降低了能耗,与常规MBR相比则节能达70%。近一年的运行表明,射流曝气对膜丝的正常工作没有任何影响,其清洗周期保持不变。     

曝气/微生物/人工湿地组合工艺处理黑臭河水

针对河北省东部某黑臭河流治理项目,开展了曝气/微生物/人工湿地组合工艺处理黑臭河水的中试研究.经过2个月的运行,在进水污染物浓度高且水质波动大的情况下,系统仍运行效果良好,COD、NH3-N、TP分别从519、11.5、6.5 mg/L左右下降到33、1.5、0.25 mg/L,出水水质达到了<地表水环境质量标准>中的V类水质标准.     

Oxygen transfer rate estimation in oxidation ditches from clean water measurements

Standard methods for the determination of oxygen transfer rate are based on assumptions that are not valid for oxidation ditches. This paper presents a realistic and simple new method to be used in the estimation of oxygen transfer rate in oxidation ditches from clean water measurements. The new method uses a loop-of-CSTRs model, which can be easily incorporated within control algorithms, for modelling oxidation ditches. Further, this method assumes zero oxygen transfer rates (KLa) in the unaerated CSTRs. Application of a formal estimation procedure to real data revealed that the aeration constant (k = KLaVA, where VA is the volume of the aerated CSTR) can be determined significantly more accurately than KLa and VA. Therefore, the new method estimates k instead of KLa. From application to real data, this method proved to be more accurate than the commonly used Dutch standard method (STORA, 1980).     

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.     

The optimum operational condition of membrane bioreactor (MBR): cost estimation of aeration and sludge treatment

A methodology to obtain the most economical operational condition of membrane bioreactor (MBR) is developed. In order to achieve the optimum design parameters of MBR with which operational costs are minimized, aeration and sludge treatment costs were estimated for various operational conditions. Generally sludge treatment cost and aeration cost were inversely proportional to each other, which means sludge treatment cost is minimized when aeration cost is maximized and vice versa. Therefore, there might exist an optimum point between the two extreme cases. However, sludge treatment cost turned out to overwhelm the aeration cost over the reasonable operational conditions. Therefore, sludge minimization was considered to be a key for the economical operation of MBR. In the case of typical municipal wastewater of which COD was 400mgL(-1), steady-state MLSS was expected to increase from 11,000 to 15,000mg/L without sludge removal when HRT was decreasing from 16 to 12h. For the range of operational conditions considered in this study, economically optimum HRT and target MLSS were turned out to be 16h and 11,000mg/L, respectively. Under this condition, aeration for the biodegradation of organic matters would be 13.3m(3) air/min when influent was 1000m(3)/day.     

疏水性中空纤维微孔膜无泡曝气试验研究

利用疏水性聚偏氟乙烯(PVDF)中空纤维膜及组件开展膜无泡曝气研究.通过检测膜组件的泡点,发现一定浸没深度下静水中膜组件的泡点高于紊流状态下的,且泡点随水流速度的增大而减小.考察水力条件和曝气压力对曝气效果的影响,并与常规曝气头曝气作比较.结果表明:将气压控制在泡点以内时,充氧能力随液体循环流量的增大、气压的升高而增强;而当气压超过泡点时,供氧初期充氧能力显著,但随曝气时间的延长增幅降低.中空纤维膜的曝气性能优于曝气头的.