Treatment of a dyeing wastewater from a woolen mill using an A/O membrane bio-reactor

An anaerobic/oxic membrane bioreactor (A/O MBR) was used for treatment of dyeing wastewater from a woolen mill.COD and color of the wastewater were 54-473 mg/L and 40-400 dilution time (DT) respectively. The ratio of BOD5/COD was less than 0.13. By the A/O MBR process, the average removal of COD, BOD5, color and turbidity was 82％, 96％, 71％ and 99％, respectively. The average COD, BOD5, color and turbidity of effluent was 37 nag/L, 0.8 mg/L, 40 DT and 0.44 NUT respectively. The effluent COD met the local standard of reuse water in Beijing, China. The average COD volume load of the anaerobic biological tank was 0. 0483 kgCOD/(m3·d) and that of the aeration tank of the MBR was 0. 3589 kgCOD/(m3·d). The sludge load of the MBR was 0.19 kgCOD/(kg· MLSS· d) on average and the maximum of that was 0.4 kgCOD/( kg· MLSS· d).The flux of the A/O membrane bioreactor could be remained at larger than 50 L/(h· m2· 0.1MPa). The results indicated that A/O membrane bioreactor has technical feasibility for treatment of woolen mill wastewater.     

A pilot scale anoxic/oxic membrane bioreactor (A/O MBR) for woolen mill dyeing wastewater treatment

A pilot-scale( 10 m^3/d) anoxic/oxic membrane bioreactor( A/O MBR) was tested for dyeing wastewater treatment of woolen mill without wasting sludge in 125 days operation. Results showed that the effluent quality was excellent, i.e. effluent COD less than 25 mg/L,BOD5 under 5 mg/L, turbidity lower than 0.65 NTU, and colour less than 30 DT, and met with the reuse water standard of China. The removal rates of COD, BOD5, colour, and turbidity were 92.4%, 98.4%, 74% and 98.9%, respectively. Constant-flux operation mode was carried out in this study, and backwash was effective for reducing membrane fouling and maintaining constant flux. Membrane fouling had heavy impact on energy consumption. More attention should be paid on pipe selection and design for the sidestream MBR system, too.     

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. Translated from Environmental Science, 2005, 26(6): 65–70 [译自: 环境科学]     

厌氧平板膜生物反应器连续处理猪场废水研究

本研究以实际猪场废水为原料,在中温（37±1）℃条件下利用浸没式平板膜生物反应器进行180d连续厌氧发酵试验,以水力停留时间5,3和2d的梯度变化逐渐增加容积负荷,研究反应器运行性能,污泥比产甲烷活性,膜过滤特性和膜的清洗效果.试验结果表明,随水力停留时间的缩短,反应器的容积产沼气率分别达到0.68,1.03和1.12L/（L·d）,稳定运行期间出水的总挥发性脂肪酸分别为（169±41）mg/L,（15±3）mg/L和（114±45）mg/L,以乙酸为主.反应器中厌氧污泥的乙酸比产甲烷活性测试表明,以2000mg/L的乙酸为基质,HRT 3d时具有最大比产甲烷活性1.127g-COD/（g-VSS·d）.本试验发生膜污染的周期约4个月.采用2%的柠檬酸浸泡3h,可以恢复膜的过滤性能.在较低通量下,反应器中7~32g/L的污泥浓度并不会明显的影响平板膜的过滤性能.本研究结果显示,厌氧膜生物反应器有处理猪场废水的可能性.     

复合式膜生物反应器处理生活污水

采用以粉末活性炭(PAC)作为填料的复合式膜生物反应器处理小区生活污水.该反应器在不人为排泥,不对膜进行任何处理(不空曝、不清洗)的情况下,连续运行100d.结果表明,系统运行稳定,出水水质优良(COD<25mg/L,NH₄⁺-N<0.6mg/L,无色无味,无SS,没有检测出大肠杆菌).PAC不仅改善了膜生物反应器中的污泥混合液的沉淀性能与可过滤性,同时也改善了膜表面滤饼层的水力特性,从而达到了减小膜过滤阻力,延缓膜污染的目的,而且还降低了运行成本.     

Advanced treatment of dyeing wastewater towards reuse by the combined Fenton oxidation and membrane bioreactor process

The performance of combined Fenton oxidation and membrane bioreactor (MBR) process for the advanced treatment of an effluent from an integrated dyeing wastewater treatment plant was evaluated. The experimental results revealed that under the optimum Fenton oxidation conditions (initial pH 5, H 2 O 2 dosage 17 mmol/L, and Fe 2+ 1.7 mmol/L) the average total organic carbon (TOC) and color removal ratios were 39.3% and 69.5% after 35 min of reaction, respectively. Results from Zahn-Wallens Test also represented that Fenton process was effective to enhance the biodegradability of the test wastewater. As for the further purification of MBR process, TOC removal capacity was examined at different hydraulic retention times (HRT) of 10, 18 and 25 hr. Under the optimum HRT of 18 hr, the average TOC concentration and color of the final MBR effluent were 16.8 mg/L and 2 dilution time, respectively. The sludge yield coefficient was 0.13 g MLSS/g TOC and TOC degradation rate was 0.078 kg TOC/(m 3 ·day). The final effluent of MBR can meet the reuse criteria of urban recycling water-water quality standard for miscellaneous water consumption GBT18920-2002.     

Biodegradation of trace pharmaceutical substances in wastewater by a membrane bioreactor

The biodegradation of selected pharmaceutical micropollutants, including two pharmaceuticals with argued biodegradation, was studied by a lab-scale membrane bioreactor. The reaction kinetics and affecting factors were also investigated in this paper. Clofibric acid (CA) with contradictive biodegradation reported was degraded almost completely at different hydraulic retention times (HRTs) after adaptation to microorganisms. The biodegradation of CA was disturbed at low pH operation, while the activity of microorganisms recovered again after pH adjustment to neutral condition. Ibuprofen (IBP) degraded under neutral and acidic conditions. Removals of IBP and CA were zero-order and first-order reactions under high and low initial concentrations, respectively. Carbamazepine and diclofenac were not degraded regardless of HRTs and pH.     

Test of membrane bioreactor for waste water treatment in a petrochemical complex

Membrane bioreactor (MBR) used in water and waste water treatment is a developing technique for water pollution control and water reuse. This paper describes a membrane-bioreactor for treatment of waste water in a petrochemical complex. The experimental MBR was a lab scale one composed of an activated sludge bioreactor unit and an ultrafiltration membrane unit. The relationship of COD removal with MLSS and HRT in this MBR was studied. The effects of crossflow velocity, backwash interval and volume of flush liquid on the flux were discussed. The results showed that average removal of COD, oil, SS and turbidity in petrochemical waste water by the MBR was 91%, 86%, 92% and 99% respectively. The average removal of NH3-N and total phosphorous was 85% and 82%. A coefficient of COD removal, k, was 0.017-0.080 L/(mg.d). The membrane flux maintained higher than 60 L/hm2 bar for 34 days without chemical cleaning when the velocity of crossflow was 3.5-3.9 m/s and the backwash interval was 30 minutes and backwash duration at 20 seconds. The results indicated that it is feasible for MBR technology to be used in petrochemical waste water treatment. The treated water could be considered as a source used to make up water for industrial cooling system or to be reused for other purposes.     

生物-微电解组合工艺处理染料废水研究

采用上流式污泥床过滤器（upflow blanket filter，UBF）＋曝气生物滤池（biological aerated filter，BAF）＋微电解的组合工艺，对盐度接近2％、色度和COD分别约为8000倍和600．5mg／L的染料废水进行处理。经过连续120d的稳定运行后，组合系统处理效果良好，脱色率和COD去除率分别达到99％和75％以上。UBF和微电解单元均可以大幅度提高废水的可生化性，有利于进一步的生物处理。UV—Vis扫描和GC—MS分析表明，该组合工艺能破坏染料的发色基团和共轭双键，并能高效降解原水中的酚类、氯代有机物和复杂的杂环类化合物。实验结果表明，UBF＋BAF＋微电解的组合工艺是处理染料废水的一种有效方法。     

膜生物反应器净化石油化工污水的研究

介绍了将膜生物反应器用于石油化工污水净化的研究，研制了一套实验室规模的好氧分离式膜生物反应器，膜组件为中空纤维超滤膜，生物反应器为活性污泥曝气池。该实验装置对石油化工污水中ＣＯＤ、ＢＯＤ５、ＳＳ、浊度、石油类的去除率分别为７８％－９８％、９６％－９９％、７４％－９９％，９８％－１００％，８７％；出水中ＣＯＤ、ＢＯ５、ＳＳ、浊度、石油类分类为１５．８－６８．６ｍｇ／Ｌ，２．４－７．８ｍｇ／Ｌ、１．２     

生化—混凝沉淀—砂滤工艺处理毛巾印染废水

根据毛巾印染废水水质特点 ,选择了厌氧折流板反应池 -生物接触氧化池 -混凝沉淀 -砂滤处理工艺。运行结果表明 ,在进水水质为 :CODCr5 89～ 2 980 mg/L、BOD5 2 49～ 5 3 4 mg/L、SS12 3～ 190 mg/L、色度 3 0 0～80 0倍、p H8.76～ 9.5 6时 ,出水水质达到《纺织染整工业水污染物排放标准》( GB42 87— 92 )一级标准。该处理系统耐冲击负荷 ,运行稳定、简单 ,基建和运行费用较低。     

巴西基酸生产废水膜生物工艺处理试验研究

采用间歇式好氧膜生物工艺（好氧曝气－超滤）对巴西基酸生产废水进行了处理实验研究,结果表明,在其它条件一定,操作周期为１２、２４、３６、４８ｈ时,超滤液ＣＯＤ浓度分别为１６０、１５１、１３９、１６０ｍｇ／Ｌ,水通量逐步提高;当容积负荷为１．２、２．４、３．６、４．８ｋｇ／ｍ^３ｄ时,超滤液ＣＯＤ浓度变化不大,但水通量下降;当泥龄分别为５、１０、２０、５０ｄ时,超滤波ＣＯＤ浓度分别为３０３、２６０、１７１、１６９ｍｇ／Ｌ,水通量上升。     

新型固定化细胞膜反应器脱氮研究

研究了一种新型的废水土生脱氮反应器，即利用固定化细胞膜将反应器一隔为二，膜的侧与好氧的氨氮废水接触，另一侧与缺氧的乙醇 水溶液（反硝化碳源）接触，固定于膜中的硝化细菌将氨氮氧化成亚硝氮和硝氮，随即被同一膜中的反硝化细菌还原成氮气。硝化细菌和反硝化细菌混合固定于膜内时的氨氧化速率约为硝化细菌单独固定时的2倍。未发现碳源重复利用对脱氮过程产生不利影响。此新型反应器 可以稳定运行50天以上。     

膜生物反应器处理毛纺废水的中试研究

采用中试规模(10t/d)的厌氧-好氧膜生物反应器(A/O MBR)处理毛纺印染废水.当HRT为7h,进水COD、BOD₅分别为179～358mg/L和44.8～206mg/L,试验系统对COD、BODs、色度、浊度的平均去除率分别为92.1%、98.4%、60.7%、98.9%,出水水质浓度或指标值分别为20.2mg/L、1.6mg/L、25倍、0.51 NTU.出水水质指标达到建设部生活杂用水水质标准(CJ25.1-89).A/O MBR工艺处理毛纺印染废水技术可行、操作简单、易于管理,可为工业规模应用提供技术参考.     

厌氧反应器与好氧MBR组合工艺处理毛纺印染废水试验研究

采用厌氧反应器与膜生物反应器(MBR)组合工艺处理毛纺印染废水,结果表明,当进水COD、BOD₅和色度分别为128～321 mg/L、36～95 mg/L和40～70倍时,出水COD、BOD₅、色度、浊度的平均值分别为36.9 mg/L、3.7 mg/L、21倍、0.24 NTU,平均去除率分别达到80.3%%、95%、59%、99.3%,达到生活杂用水水质标准.在本研究中,开发了一种新型的利用生物反应器内液位水头重力驱动连续出水的重力出流式膜生物反应器.在保留MBR处理效率高等优点的同时,省去传统的一体式MBR出水抽吸泵及复杂的反冲洗设备.整个系统结构紧凑,投资少,操作简便.选择合适的曝气量有助于提高膜通量,且可降低膜阻力的上升速率,有利于膜污染的控制.     

浸没式双轴旋转厌氧膜生物反应器处理啤酒废水试验

研究了新型浸没式双轴旋转厌氧膜生物反应器(SDRAnMBR)处理模拟啤酒废水的运行性能.研究结果表明,SDRAnMBR对啤酒废水有较好的处理效果,处理过程负荷提高快,有机物去除率高,系统耐冲击负荷的能力强,而且运行非常稳定.正常运行期间,进水COD在2900～5200mg·L-1,容积负荷为4.97～12.48kg·m-·3d-1(以COD计)时,COD的平均去除率为95.15%.膜截留和三相旋转流的共同作用,加强了在高污泥浓度(MLSS)和高负荷条件下运行时的混合和传质,从而强化了SDRAnMBR在高MLSS和高容积负荷下运行的稳定性和出水水质.     

盐度对膜-生物反应器污泥表观硝化速率的抑制机理

为研究盐度对膜-生物反应器(MBR)污泥表观硝化速率的抑制机理,采用批次试验模拟不同盐度条件下MBR活性污泥的硝化反应并测定其表观硝化速率、自养菌活性和SMP、EPS中脱氧核糖核酸和蛋白质的含量变化.结果表明,随着盐度的不断提高,污泥表观硝化速率逐渐下降,当盐度大于12.5g/L时,污泥体系出现NH4+-N含量上升的现象.自养菌的活性逐渐被抑制,抑制程度和盐度正相关,当盐度大于2.5g/L时,SMP和EPS中DNA的含量逐步上升,细胞结构被破坏是微生物活性被抑制的原因.SMP和EPS中蛋白质含量随着盐度的提升明显增长,蛋白质在污泥系统水解并发生氨化释放NH4+-N也是表观硝化速率下降的原因;当盐度小于12.5g/L,系统释放NH4+-N对表观硝化速率抑制作用随着盐度的提高而不断提升.     

基于新型载体AMC/UASB-SCMBBR生物工艺处理印染废水的中试研究

针对泉州某印染厂实际废水(COD 800～1800 mg·L~(-1),NH~+_4-N 20～50 mg·L~(-1),pH=8～14),以两种新型载体分别作为厌氧与好氧单元中微生物固定化载体,考察了中试规模上流式厌氧污泥床反应器(UASB)与柔性悬浮载体移动床生物膜反应器(SCMBBR)组合工艺对该废水的处理效果.4个月的连续试验结果表明:①经过30 d前期调试运行该工艺系统成功启动,处理量为1.5～2.2 m~3·d~(-1)时,AMC/UASB和SCMBBR反应器对COD的去除率分别达到22%和50%,AMC/UASB反应器出现明显的产气现象,SCMBBR中载体挂膜状况良好;②启动完成后经过90 d的连续运行,当AMC/UASB和SCMBBR反应器水力停留时间分别为10.7 h和8.8 h,废水处理量为5 m~3·d~(-1)时,稳定运行阶段整个工艺废水COD去除率达到78%,出水氨氮平均浓度为3.4 mg·L~(-1);此外,整体工艺色度去除率达到65%,其中,厌氧段色度去除率达到50%左右;③通过分析计算,整个系统污泥减量达到67.7%～76.6%,该生物组合工艺具有明显的污泥减量效果.     

内循环动态膜生物反应器处理生活污水

利用筛绢为基材构建内循环动态膜生物反应器处理生活污水.在水力停留时间为6h,膜通量为66.2L/(m²·h)条件下,反应器内的生物动态膜需要120min可以形成.动态膜形成后,反应器对COD、氨氮、总氮(TN)和总磷(TP)的平均去除率分别为94.0%、97.6%、49.2%和83.7%.采用逆出水水流方向曝气进行在线反冲洗,在反冲洗时间为5min,反冲洗曝气强度为3.2m³/(m²·h)的条件下,生物动态膜的再生需要30min即可完成.反应器稳定运行60d,反冲洗周期能够稳定在50h以上.扫描电镜(SEM)观察表明,反冲洗能够有效破坏附着在膜基材上的生物动态膜.     

O/A/O组合工艺在浆染废水处理中的应用

以如皋常青某印染厂废水处理中心为例，介绍了O／A／O组合工艺处理浆染废水的工程设计。设计处理规模为1000m^3／d，进水COD为1200mg／L，处理后出水达国家一级排放标准。实践证明这是一种处理可生化性较差、难降解废水的行之有效的工艺。