超滤膜净化水库水试验研究

用中空纤维超滤膜处理哈尔滨附近B水库水,以替代混凝、沉淀、砂滤的传统自来水生产方法,研究生产饮用水的新工艺.研究了原水温度、浊度、操作压力和混凝剂的加入量对膜通量的影响.研究发现超滤膜通量与膜进水浊度的对数成反比,跨膜压力增大、适当加入混凝剂,膜通量增加.超滤出水和传统工艺的出水进行了比较,超滤膜出水浊度小于0.2 NTU,明显好于传统工艺的出水浊度.对超滤处理后的出水水质进行了全分析,超滤对铁、铝、锰、色度、好氧量、总有机碳等均有较好的处理效果,完全满足饮用水水质的标准.     

海水淡化中连续膜过滤技术的工艺优化研究

研究了PVDF中空纤维膜为核心的CMF系统在海水淡化预处理应用中的工艺优化问题.经过长期的运行实验表明:最佳运行工艺条件是工作时间35 min,气水双洗30 s,反冲洗25 s,排污15 s.在气水双洗工艺中,当压缩空气储罐压力大于0.5 MPa时清洗效果最好.使用CMF进水配制的清洗剂中,NaClO和HCl相结合的化学清洗效果最好.CMF系统的出水浊度始终稳定在0.06~0.07 NTU之间,SDI值一直稳定在1~2之间,系统收率维持在96.3%.     

倒置A~2O-MBR工艺处理城市生活污水脱氮除磷中试研究

利用天津膜天膜科技股份有限公司生产的中空纤维帘式膜组件,并采用自行设计的MBR中试设备构建倒置A2 O-MBR工艺处理城市生活污水.结果表明,该工艺的产水COD、NH3—N、TN、TP平均值分别为22.23mg/L、1.89mg/L、14.96mg/L、0.38mg/L,去除率分别为91.49%、94.5%、63.4%、87.3%,出水浊度0.19NTU.出水主要水质指标在系统运行正常时可以达到《城镇污水厂污染物排放标准》(GB 18918—2002)一级A标准.一般情况下,出水水质可以保证符合一级B标准的要求.对于已污染的膜,采用复合碱性溶液浸泡循环清洗、碱性溶液和酸性溶液依次浸泡循环清洗两种方法可分别使跨膜压差由43kPa降至12kPa,73kPa降至25kPa,压差下降量分别为31kPa、48kPa,恢复产水.     

纳滤组合工艺深度处理微量污染物

以污水处理厂的二级出水为处理对象,研究纳滤组合工艺(微滤-活性炭过滤-微滤纳滤)对微量污染物的处理效果.结果表明,该工艺对浊度和TOC均有较好的去除效果,出水平均值分别为0.13 NTU、1.93 mg/L;对重金属砷、镉、铅的平均去除率分别为54.94%、86.73%和83.40%;对邻苯二甲酸酯类物质的截留效果较好,其中DBP和DEP的平均去除率分别为78.91%和78.95%.     

浸没式新型PVC膜生物反应器在市政污水处理应用研究

利用一套浸没式新型PVC(Polyvinyl chloride)超滤膜材料的膜生物反应器(membrane bioreactor,MBR)处理市政污水,研究了该新型PVC-MBR的长期运行效果、运行状况及膜污染控制效果.结果表明:新型PVC-MBR对主要污染物COD、NH4+-N、TP和浊度等有很好的去除效果;对COD、NH4+-N去除率分别可以稳定在90%和95%以上;外加化学混凝辅助除磷条件下运行可保证出水TP小于0.5mg/L;膜出水浊度小于0.1NTU,出水水质可达到城市杂用水水质标准(GB/T 18920—2002)的要求.在20L/(m2·h)通量条件下,膜系统运行稳定,跨膜压差(TMP)基本保持在-35kPa以内,在第195天进行离线化学清洗,通过1×10-3NaClO和质量分数0.2%NaOH混合离线清洗后可以使膜运行的TMP恢复至接近新膜通量的水平.     

混凝和微滤膜组合工艺处理稠油污水的研究

以辽河油田某稠油污水处理厂外排水为对象,采用混凝与微滤膜(MF)处理相结合的方法.从操作压差、膜孔径、混凝处理等多个角度对稠油污水膜分离及组合工艺进行条件优化和效果分析.确定选择0.5 μm孔径膜、0.25 MPa操作压差为膜最佳操作运行条件;通过常规的混凝和膜分离联合处理方法可有效去除稠油废水中悬浮性及部分可溶性有机污染物,处理后出水COD平均浓度86～97 mg/L,去除率达到43.4 %;且膜清洗通量能够恢复96.8%.结果表明该工艺远优于传统工艺,可以作为稠油污水二级处理保障工艺.     

等离子改性PVDF超滤膜在MBR中耐污染性能研究

对聚偏氟乙烯(PVDF)中空纤维超滤膜进行丙烯酸(Acrylic Acid,AA)等离子体化学沉积改性,傅里叶衰减全反射红外光谱(FT-IR)、扫描电镜(SEM)、能谱仪(EDS)及力学性能试验分析表明,膜表面引入了羧基,成功接枝了AA聚合单体,且改性膜柔韧性得到提高,改性后膜清水通量增加了12.04%~16.12%.采用浸没式MBR反应器,在气水比为20∶1条件下对改性膜与原膜进行平行对比实验,实验表明,表面性能的改变可有效阻碍滤饼层污染物在膜表面沉积与压实.经水力及化学清洗后,改性膜通量恢复率都略高于原膜,抗滤饼层污染的能力得到提高.改性膜与原膜出水浊度为0.0~0.6NTU,COD去除率数据表明改性膜出水效果略优于原膜.     

A/O MBR处理城市污水回用的中试研究

采用中试规模(36 m3/d)的缺氧-好氧膜生物反应器(A/O MBR)对城市污水处理回用进行了试验研究.试验结果表明,该工艺处理效果优良,系统对COD、氨氮、浊度、细菌的平均去除率分别为94%,98.3%,99.6%,lg6,出水浓度分别为18 mg/L,0.65 mg/L,0.06 NTU,4个/mL.出水水质优于城市杂用水水质标准(GB/T 18920-2002).该系统具有较强的抗冲击负荷能力.     

生物阳极辅助Ag/RGO/BiVO_4催化膜阴极系统的水处理研究

用水热法合成Ag/RGO/BiVO_4,涂覆在不锈钢网上制备得到膜电极,此膜电极兼具光催化、电催化及过滤、杀菌性能.膜组件形式的阴极与生物阳极构建成由离子交换膜分隔的两室水净化处理和产电系统,该系统在阴极膜过滤出水条件下,模拟连续运行的水处理工艺,净化实际景观水(含有藻类﹑COD和氨氮等污染物).当水力停留时间为12h时,阴极去除COD68%,平均878mg/(m~2·h),氨氮去除68.4%,且经阴极膜组件过滤后的出水较原液明显清澈;阳极室中总氮去除21%,COD去除87.5%.与处理实际景观水相比,系统对单一污染物四环素的去除效率更高(86%).此外,系统最大产电功率和开路电压分别为285.6 mW/m~2,0.361V;阴极光电催化降解四环素的主要活性物种为·O_2~-和h~+;光照下膜电极能够抑制粪大肠杆菌,进一步提高出水品质.     

微藻-膜生物反应器处理劣五类水实验研究

将微藻添加到膜生物反应器中,构建微藻-膜生物反应器(A-MBR)污水处理系统。考查了系统对废水中有机污染物、N和P的去除效果以及微藻对膜污染的影响。结果表明:A-MBR系统对化学需氧量(COD)的去除效率大于90%,出水中COD含量低于50mg/L,达到一级A排放标准。A-MBR系统相比于传统膜生物反应器系统(SMBR)对总磷去除率平均高10.1%,对NH4+-N去除率也更高。同时,A-MBR系统过膜压力差(TMP)平均增长速率比S-MBR系统下降19.4%,表明微藻可有效缓解MBR系统膜污染。     

Chemical and physical treatments of chemical mechanical polishing wastewater from semiconductor fabrication

Wastewater from chemical mechanical polishing (CMP) process of semiconductor fabrication was treated by physical methods. The CMP wastewater, as obtained from a large semiconductor manufacturer, was characterized by a high oxide particle content, high turbidity (NTU), and a chemical oxygen demand (COD) concentration up to 500 mg/l. Due to these characteristics, treatment of the CMP wastewater by either filtration or by traditional activated sludge method was inadequate. In the present work, physical methods consisting of chemical coagulation and reverse osmosis were employed to tackle the turbidity and COD problems. Experimental tests were conducted to assess the effectiveness of the treatment and to identify the optimum operating conditions. Test results clearly demonstrated the complementary advantages of the two methods. The treatment was capable of realizing over 99% oxide particle removal and lowering the wastewater COD to below 100 mg/l. The overall water quality of the final effluent was excellent and can be considered for reuse. Preliminary treatment of the RO retentate by ozonation was also attempted. The COD removal achieved in the ozonation was over 80% in an hour, rendering the treated RO retentate suitable for direct discharge.     

膜法浓缩己内酰胺废水

为研究己内酰胺生产过程中废水的膜处理条件,以巴陵石化己内酰胺生产废水为研究对象,采用反渗透膜处理工艺,在一定条件下,考察浓缩倍数对膜通量及浓缩液和透过液的水质,包括电导率、COD、pH的影响.结果表明,反渗透膜能有效地处理己内酰胺生产过程的部分废水,且水质稳定.在适宜浓缩倍数下,离子交换过程中产生的反冲洗废水的透过液水质可达到我国工业废水排放标准,聚合废水透过液也能满足生化处理要求,对于本实验采用的原料液,离子交换废水的处理控制浓缩倍数为8左右,聚合废水浓缩4～5倍较合适.     

Date-palm fibers media filters as a potential technology for tertiary domestic wastewater treatment

A number of municipal wastewater treatment systems were developed to improve effluent water quality, however economic aspects should be considered. This study was thus carried out to investigate the application of date-palm fibers filtration as an efficient method to economically remove turbidity, phosphorus, organics in term of COD and helminth eggs of secondary domestic wastewater from an activated sludge treatment process. Column experiments were investigated to study the efficiency of date-palm fibers filters media used in this work for the removal of targeted matter under operational conditions (flow rate, filter depth, and diameter of the fibers). The results indicate that diameter of the fibers had the most significant factor affecting the removal of targeted matter. Pilot test results indicated that date-palm fibers filtration removed up to 54.9% of turbidity, 80.6% of COD, 57.7% of phosphorus and 98% of helminth eggs. Definitely, it could be concluded that the date-palm fibers could offer an appreciable economic and environmental potential, which should be in a position to effectively contribute to the valorisation of such as date-palm by-products for domestic or industrial wastewater treatment in southern of Tunisia.     

臭氧催化氧化-活性炭吸附处理DDNP废水

采用臭氧催化氧化-活性炭吸附方法处理DDNP废水,与单独臭氧氧化相比,催化剂的加入可以提高反应后期酸性环境下臭氧的氧化效率。试验选用Fe-活性炭催化组合,在曝气量为70 L/min,臭氧质量浓度为11.5mg/L的情况下处理500 mL废水,1 h后废水中COD、色度、硝基酚类化合物去除率分别达到72.6%、94.3%、80.6%;活性炭吸附处理臭氧催化氧化后DDNP废水可达到《兵器工业水污染排放标准》。当活性炭饱和导致水质超标时,采用臭氧对活性炭进行再生20 min,经反复10次试验,出水水质中COD稳定在131.47~152.96 mg/L,色度和硝基酚类化合物的含量低于排放标准,处理效果良好,具有可重复性。     

Optimization of electrochemical treatment of industrial paint wastewater with response surface methodology

The electrochemical oxidation of water-based paint wastewater was investigated batch-wise in the presence of NaCl electrolyte with carbon electrodes for the first time in literature. The electrochemical treatment conditions were optimized using response surface methodology where potential difference, reaction temperature and electrolyte concentration were to be minimized while chemical oxygen demand (COD), color and turbidity removal percents and initial COD removal rate were maximized at 100% pollution load. The optimum conditions were satisfied at 35 g/L external electrolyte concentration, 30 degrees C reaction temperature and 8 V potential difference (64.37 mA/cm(2) current density) realizing 51.8% COD and complete color and turbidity removals, and 3010.74 mg/Lh initial COD removal rate. According to these results, the electrochemical method could be a strong alterative to conventional physicochemical methods for the treatment of water-based paint wastewater.     

絮凝-微电解法处理DDNP废水实验研究

主要研究了絮凝-微电解法处理某化工厂的DDNP生产废水的工艺流程及处理效果。通过实验找出絮凝剂FeCl3的最佳用量,然后采用柱式装置通过微电解法处理DDNP废水,并考察了废水pH值、铁屑粒度、过柱流速等因素对处理效果的影响。对处理后废水的COD进行了测试,实验结果表明,通过最佳条件的选择对废水COD的去除率可以达到93．90％。     

Recycle of Alum recovered from water treatment sludge in chemically enhanced primary treatment

An investigation was made to study the feasibility of recovering the Alum from coagulation sludges and reusing it in chemically enhanced primary treatment (CEPT) process to make the CEPT more cost-effective and recover the resource (Alum) efficiently. The optimum condition and efficiency of the acidification method for Alum recovery from coagulation sludge were investigated in the test. The results show that when the recovery rate of Alum reaches its highest level, 84.5%, the reduction rate of sludge is 35.5%. It turns out that the capability of recovered coagulant to remove turbidity, UV(254) and COD are 96%, 46% and 53%, respectively. The results prove that the recovered coagulants could be used in CEPT and the efficiency of recovered coagulant to remove pollutants is similar to that of fresh coagulant. Although some substances will be enriched during recycle, they have little effect on the quality of treated wastewater. The experiments verify that it would be an advisable and cost-effective way to recover Alum from coagulation sludges in water treatment and chemical wastewater treatment, and it could be then recycled to CEPT as well as reduce sludge volume.     

Optimization of oil removal from oily wastewater by electrocoagulation using response surface method

Electrocoagulation process with sacrificial aluminium anode was used to separate oil from oily wastewater emulsion. A preliminary experimental study was performed to evaluate the most accurate operating parameters, which are then used for the determination of oil removal efficiency. An experimental design using response surface method (RSM) was then applied and oil separation was estimated by measuring turbidity and chemical oxygen demand (COD). An optimal region characterised with low values of turbidity and COD was found. As part of the optimized process, the main effects of the operational parameters were also investigated. The experimental results indicated that electrocoagulation was very efficient and able to achieve 99% turbidity and 90% chemical oxygen demand (COD) in less than 22 min and current density of 25 mA cm(-2). Analysis of variance (ANOVA) showed a high variance coefficient (R(2)) value of 0.998, thus ensuring a satisfactory adjustment of the second-order regression model with the experimental data.     

A combined electrocoagulation-sorption process applied to mixed industrial wastewater

The removal of organic pollutants from a highly complex industrial wastewater by a aluminium electrocoagulation process coupled with biosorption was evaluated. Under optimal conditions of pH 8 and 45.45 Am(-2) current density, the electrochemical method yields a very effective reduction of all organic pollutants, this reduction was enhanced when the biosorption treatment was applied as a polishing step. Treatment reduced chemical oxygen demand (COD) by 84%, biochemical oxygen demand (BOD(5)) by 78%, color by 97%, turbidity by 98% and fecal coliforms by 99%. The chemical species formed in aqueous solution were determined. The initial and final pollutant levels in the wastewater were monitored using UV-vis spectrometry and cyclic voltammetry. Finally, the morphology and elemental composition of the biosorbent was characterized with scanning electron microscopy (SEM) and energy dispersion spectra (EDS).     

Treatment of refractory organics from membrane rejects using ozonation

The reject water or retentate generated from membrane application for recovery of water from tannery wastewater treatment contains certain refractory organics. These refractory organics are present in substantial quantity in the condensate of reject water also. Hence the treatment of rejects using conventional methods is rather difficult. In this paper, an attempt has been made to treat the reject water from the reverse osmosis (RO) and nano filtration (NF) operation on tannery wastewater using ozonation treatment technique. Ozonation studies on RO and NF rejects indicate that ozone dose of 80 and 100mg/min for 60 and 70 min contact time achieves 59 and 78% chemical oxygen demand (COD) reduction, respectively. The mass balance in ozone indicates the ozone consumption for RO and NF rejects varies from 2.4 to 3.4 and 2.8 to 4.5 g/g of COD removed respectively. The results suggest that ozonation of RO and NF rejects would significantly reduce the refractory organic pollutant loading into the environment from wastewater reuse facility.