Reduction of chlorophenols and sludge management from paper industry wastewater using electrocoagulation process

ABSTRACT

In this study, electrocoagulation (EC) was used to determine the optimum conditions on the basis of maximum chemical oxygen demand (COD) and color removal. At the optimum conditions chlorophenols (CPs), biological oxygen demand and total organic carbon (TOC) were determined. The biodegradability of wastewater was increased significantly with 63% COD, 98% color, 61% TOC and overall 65.51% reductions in CPs. Further, the electro-coagulated sludge was characterized by using different analytical techniques to assist the physicochemical and elemental phases, to find-out better management option, reusability for plant growth and safe disposal. Additionally, aluminum content (70.62%) was successfully recovered from sludge.     

电-Fenton法在水处理中的研究现状及发展趋势

综述了电-Fenton法的各种类型以及在水处理应用中的国内外研究现状,指出电-Fenton法适用于处理含较高浓度有机物、且有毒性的废水,是一种快捷、经济、高效的废水处理方法.同时提出了电-Fenton法存在的问题和发展趋势,为该法的更深入研究提出了建议.     

电絮凝水处理技术阳极优化的研究

简介了电絮凝法处理废水的基本原理,重点探讨了目前电絮凝水处理技术中存在的阳极钝化问题,以及影响阳极钝化的主要因素,并提出了解决阳极钝化的方法和建议.在实际处理工艺中,可以从采用新型电极、磁场效应以及改进电源技术等方面着手,对工作阳极做进一步优化,降低电能消耗和材料消耗,以促进电絮凝水处理技术的推广应用.     

高压脉冲电絮凝处理综合电镀废水的试验研究

采用高压脉冲电絮凝技术处理某电镀厂的电镀废水,考察了高压脉冲电絮凝设备对Cu2＋、Ni2＋、CN-和CODCr的去除效果.结果表明,高压脉冲电絮凝技术对电镀综合废水的处理效果显著,Cu2＋、Ni2＋、CN-和CODCr的去除率分别可以达到99.80％、99.70％、99.68％和67.45％,达到GB 8978-1996《污水综合排放标准》的要求.该高压脉冲电絮凝技术处理电镀废水具有处理效率高、速度快、占地面积小、操作方便的特点,有良好的工程应用前景.     

基于响应面法的电絮凝处理高浓度聚丙烯酰胺废水工艺优化

为探讨电絮凝技术去除高浓度含聚废水中的聚丙烯酰胺(PAM)的效果,通过单因素试验分析讨论了电流密度、极板间距、极板材料、电解时间和聚合物浓度对处理效果的影响.使用Box-Behnken响应面法分析因素之间的显著关系,以优化最佳操作条件.对于PAM初始质量浓度为800 mg/L的模拟废水,确定最佳参数:极板间距为2.60...     

The addition of hydrogen peroxide in the electrocoagulation treatment for improving toxic organic matters removal: A comparative study

The role of hydrogen peroxide (H₂O₂) in the electrocoagulation (EC) treatment for removing toxic organic matters in wet-spun acrylic fibers (WAFs) manufacturing effluents was investigated. The addition of H₂O₂ in the EC resulted in electro-Fenton (EF) treatment, which improved the removal of organic pollutants. Biodegradability of the EF-treated effluents was significantly improved over the EF treatment and reached 0.18. In addition, evaluation of the toxicity of the treated effluents using luminous bacteria revealed that the EF treatment resulted in the greater removal of toxic compounds than the EC treatment, with 80.9% decline in the EC₅₀.     

Advanced treatment of copper smelting wastewater by the combination of internal micro-electrolysis and electrocoagulation

ABSTRACT

In this study, a combined process of internal micro-electrolysis (IME)–electrocoagulation was developed at lab scale for treating a real copper smelting wastewater. By IME, 92.4% of Cu, 88.6% of Pb, and 72.2% of Zn were removed after 30 min at an initial solution pH of 3, a Fe/C dosage of 40 g/L, and a Fe/C mass ratio of 1:1. Removal of residual metals by electrocoagulation was affected by wastewater pH and current density. Electrocoagulation with iron/aluminum electrodes at a current density of 5 mA/cm², electrocoagulation time of 30 min, and pH 8 resulted in 99.3% Cu, 99.5% Pb, and 98.6% Zn removal. The final effluent quality could satisfy the National Discharge Standard of China. This work demonstrates that the hybrid system has the potential to be applied for the advanced treatment of high-strength copper smelting wastewater.     

三维电极-电Fenton法处理甲醛模拟废水试验研究

采用三维电极-电Fenton法处理模拟甲醛废水,考察了甲醛废水中有机物去除的影响因素及处理效果,优化了试验条件。正交试验结果表明,各因素对甲醛去除率影响程度大小依次为：电解时间〉pH4g〉电解电压〉极板间距〉甲醛初始浓度。最佳去除条件为：甲醛初始质量浓度为300mg／L,pH值为3,极板间距为2．0cm,电解电压为9V,电解时间为90min。在此条件下,甲醛去除率达到95．7％,COD。和TOC去除率分别迭91．5％和92．4％。三维电极一电Fenton法用于甲醛废水处理切实可行,效果明显,为实际废水处理提供了参考。     

炼油污水A/O处理工艺模拟与优化

针对我国某炼油厂含油系列污水处理生化段缺氧/好氧(A/O)工艺,利用BioWin 5.0模拟软件,进行了模拟和优化。结果表明,校正后的模型能够较好地反映目前A/O工艺的运行状况。然后调节工艺参数对校正后的模型进行优化,结果表明:在优化后的运行条件下,出水COD几乎没有变化,TN去除率提高2.9%,曝气能耗下降了17.8%,节约了运行费用。     

电絮凝法处理含油废水的研究

通过石墨-石墨、铝-石墨、铅-石墨、铁-石墨和铝-铁等5种电极组合分别处理含32#机油的废水。研究发现，铝-石墨为最佳电极组合，通过正交实验设计，选择固体悬浮物(SS)、化学需氧量(COD)和含油量的去除率较大的条件是：电解质(NaCl)为3g，电解电压为10V，电解时间为25min。     

铝铁电极电絮凝法处理镀镉废水的研究

为了探讨电絮凝法对钢铁厂镀镉废水的处理效果,先对铝铁电极活化预处理后,采用电絮凝法原理对镀镉废水中的镉离子去除净化。系统地分析了铝电极的极化效应,对影响絮凝体的平均粒径、含量、镉离子去除率的因素进行探讨。结果表明：最佳电解时间为70 min,此时絮凝体平均粒径为54 μm,含量为3.80 g/L。铝铁电极的阳极极化效应强于阴极极化效应。当起始pH=4.0、极板间距为20 mm、极板电压为5 V、电流密度为30 mA/cm²时,Cd²⁺初级去除率达到96.8%,三级去除率超过99.9%,废水中Cd²⁺含量达到国家现行电镀污染物排放标准。采用电絮凝法通过铝铁电极处理镀镉废水的实验效果优良。     

光伏行业含氟废水处理

太阳能光伏电池作为一种清洁能源，应用前景广泛。其生产废水因含有F-，腐蚀性强，治理困难。采用两级反应沉淀法，先添加氯化钙除氟，再加絮凝剂和助凝剂进行沉淀，在一级、二级沉淀池中分别进行沉降。结果显示，出水F一质量浓度降至10mg／L以下，达到《污水综合排放标准》（GB8978-1996）的一级排放标准，解决了企业废水处理问题，废水处理效果好，运行稳定，具有推广价值。     

线路板油墨废水深度净化的中试研究

采用Fenton氧化+电絮凝+膜过滤+活性炭工艺对东莞某线路板生产企业的废水进行处理,通过中试实验考察了该工艺的可行性。结果表明:此工艺的COD去除率为99%,氨氮的去除率达98%,对TP的去除率达78%~90%,对TN的去除率达99%,对Cu、Pb、Cr、Ni的去除率分别为98.38%、98.16%、59.11%、57.61%,出水水质均达到(GB 21900—2008)表3标准的要求。     

电子行业废水MBR法处理回用中试研究

使用MBR中试装置对电子行业废水的处理回用进行了实验研究,并对MBR系统的清洗及污泥性状进行了分析。结果表明,MBR系统对电子行业废水中的COD、氨氮、磷等污染物均有较好的处理效果,处理出水可达到《城镇污水处理厂污染物排放标准》(GB 18918—2002)中的一级标准,出水经RO系统进一步处理可得到高品质的回用水。     

煤化工废水回用技术的应用分析

介绍回用技术在煤化工废水处理中的应用,阐述煤化工废水回用技术是多种技术和方法的综合,是根据煤化工废水的来源、水质特点以及回用水质要求来设计,并指出回用技术是煤化工废水处理的发展趋势。     

铁碳微电解深度处理橡胶工业废水的试验研究

采用铁碳微电解法对橡胶工业废水进行了深度处理试验研究,考察了初始pH值、反应时间、铁碳投加量等因素对处理结果的影响。结果表明在反应初始pH值为3,反应时间为120 min,铁碳占总体积的40%时,经过处理后废水中CODCr的质量浓度由168 mg/L可降到46 mg/L。该技术作为橡胶废水深度处理技术是可行的。     

A property-based optimization of direct recycle networks and wastewater treatment processes

This article presents a mathematical programming approach to optimize direct recycle-reuse networks together with wastewater treatment processes in order to satisfy a given set of environmental regulations. A disjunctive programming formulation is developed to optimize the recycle/reuse of process streams to units and the performance of wastewater treatment units. In addition to composition-based constraints, the formulation also incorporates in-plant property constraints as well as properties impacting the environment toxicity, ThOD, pH, color, and odor. The MINLP model is used to minimize the total annual cost of the system, which includes the cost for the fresh sources, the piping cost for the process integration and the waste stream treatment cost. An example problem is used to show the application of the proposed model. The results show that the simultaneous optimization of a recycle network and waste treatment process yields significant savings with respect to a commonly-used sequential optimization strategy. © 2009 American Institute of Chemical Engineers AIChE J, 2009     

非线性污水处理过程的多目标优化

研究了复杂非线性污水处理过程的多目标优化。针对污水处理过程的非线性动力系统,建立了使污水处理过程运行成本和描述实际输出与期望输出偏差的平方可积误差设计指标同时达到最优的多目标优化模型。采用间接优化方法,首先将描述污水处理过程优化的多目标非线性问题转化为多目标线性规划问题,然后利用遗传算法对其进行求解。本文方法不仅获得了多目标优化问题的近似Pareto前沿,而且由于采用的是多目标线性规划方法,所以具有计算成本低的优点。     

Optimized design of wastewater treatment systems: Application to the mechanical pulp and paper industry: I. Design and cost relationships

Four different end-of-pipe waste-treatment processes applicable to mechanical pulp and paper manufacture were modelled. Calculated costs for an average mill were capital $34–$44 million, operating cost $3.5–$6 million/year and discounted (10 years) $60–$85 million. Compared with mill reported values, capital and operating costs of activated sludge treatment (AST) were higher by 17 and 29%, respectively; those for aerated stabilization basin (ASB) were higher by 27 and 180%. Major variables affecting the costs were BOD and TSS levels and the wastewater-to-pulp ratio. It was concluded that ASB is more economical than AST and that anaerobic treatment plus AST could be advantageous at high BOD levels.     

陶瓷业含酚废水的处理与酚的回收研究

采用先加入氢氧化钠反应,再进行蒸馏的方法,对陶瓷业含酚废水进行了处理及酚类物质回收的研究。探讨了氢氧化钠用量、搅拌时间以及蒸出液的体积对酚类物质去除和回收的影响。实验结果表明:对于25 mL的陶瓷业废水,氢氧化钠用量为0.9 g,搅拌10 min,蒸出液体积为15 mL,脱酚率高达96.44%,酚类物质回收率为95.12%。同时进行放大实验,脱酚率可达96.15%,酚类物质回收率仍高达94.96%,说明该方法处理陶瓷业水煤气废水的效果良好。