The significance of resource recycling for coking wastewater treatment:based on environmental and economic life cycle assessment

The sustainability of the coking industry is supported by reasonable production profit and environmental quality requirements.The traditional measures substantially increased the related costs for enterprises to reach standards.This paper aims to develop a comprehensive cost combined environmental impact assessment method that is necessary for the analysis of wastewater treatment systems.Typical three coking wastewater treatment processes in China were evaluated.Results showed that eutrophication dominantly contributed to the overall environmental effect.Improving effluent quality could significantly reduce the total environmental impact.In terms of an economic perspective,the price of raw materials was the main factor that affected the operating cost of comprehensive treatment.Based on subsystem analysis,the pretreatment stage accounted for the majority of environmental and cost burdens,respectively reaching 64%-78%and 64%-86%.Optimizing the pretreatment process by enhancing the efficiency of high concentration raw material recovery and substituting toxic raw materials for extractant could reduce the environmental impact and economic cost by 43.8%and 57%,respectively,which was an effective way to improve the potential performance of coking wastewater treatment plants(WWTPs).

A Grey Water Dam Design for the Treatment and Reuse of Grey Water from Single and Multiple Households

An innovative design for the treatment and reuse of grey water is presented in the form of a grey water dam which is an outgrowth of the vertical grey water tower. A hydraulic equation has been formulated and is presented in this paper which is used to determine the seepage path within the grey water dam, and determine the dimensions of the dam components. The hydraulic equation model also helps in avoiding soil piping problems by keeping the phreatic line within the grey water dam. Vegetables are planted around the surface of the dam as a reuse option while helping recycling of water in the form of evapotranspiration. A successful pilot trial of this dam was run in Mnyamatsini area in Swaziland which can accept grey water from multiple households.

Shear strength of clayey sand treated by nanoclay mixed with recycled polyester fiber

The main objective of this study is to investigate the effects of the nanoclay mixed with recycled polyester fiber on the mechanical behavior of soil as a new stabilizer material.To meet this objective,a series of drained direct shear and compaction tests were performed on unreinforced and reinforced soil specimens with three different combinations of the fiber-soil ratios ranging between 0.1%and 0.5%,as well as three different combinations of nanoclay soil ratios ranging between 0.5%and 1.5%of the soil dry weight.Results indicated that composition of the nanoclay recycled polyester fiber with the soil improved the friction angle(Φ)by 41%and cohesion(c)by 174%.The soil particles stick together through viscose gel produced by nanoclay.In addition,the rough and wavy surface of the fibers creates a bond and friction between the soil particles and prevents the movement of soil particles,and as a result,the soil strength is increased.

The influence of nitrified supernate’s recycle ratio on the removal of coking wastewater

The influence of the recycle ratio on the removal of coking wastewater has been researched using the anaerobicanoxic-aerobic （A/A/O） biofilm process. The research indicates that the concentrations of chemical oxygen demand （COD） and NO3 -N in the water are the lowest when the recycle ratio is 3：1 ,but the removal efficiency of total cyanide （TCN） is the highest when the recycle ratio is 1： 1. The removal efficiency of NH4^＋ -N is more than 99% at all three different recycle ratios. Compared with Grade A of the National Discharge Standard （GB 8978--1996）, the effluent NH4 -N is standard,but COD and TCN can not meet the requirements and further treatment processes are needed.

High-rate removal of As(Ⅲ) from aqueous system with sulfhydryl magnetic biological bamboo charcoal nanocomposites prepared by chemical co-precipitation method

Sulfhydryl magnetic biological bamboo charcoal nanocomposite(BBC@nFe-SH)was prepared by chemical co-precipitation method for the robust capture of As(Ⅲ)from aqueous solutions.The novel BBC@nFe-SH shows favorable magnetic field strength(83376 A/m),which enables BBC@nFe-SH to be quickly recovered from aqueous solution.The maximum As(Ⅲ)adsorption capacity is as high as 98.63 mg/g at pH 5.0 and 40°C,reaching reaction equilibrium within 120 min.Various characterizations(e.g.,SEM,FTIR,VSM and XPS)suggest that As(Ⅲ)prefers to coordinate with surface oxygen groups bonded to the surface.BBC@nFe-SH displayed high stability and recyclability throughout the removal process,which could be easily activated by 1 mol/L NaOH after usage.Thus,the novel BBC@nFe-SH has promising applications for As(Ⅲ)treatment.

Research Progress on Energy Plants in Piggery Wastewater Treatment

Large-scale pig-raising can discharge a great deal of wastewater,which contains high content of organic matter,ammonia nitrogen and suspended solids.The improper treatment of the piggery wastewater can lead to serious environmental problems. As a liquid fertilizer,piggery wastewater is relatively low in fertilizer efficiency and high in transportation cost,so it is very necessary to treat it in situ. Energy plants have the advantages of rapid growth,large biomass,strong tillering ability and developed root system. Therefore,energy plants can be used to absorb and transform the pollutants( like nitrogen and phosphorus) in piggery wastewater into the components of plants,as well as form the rhizosphere environment which is conducive to microbial growth,so as to enhance the effects of nitrogen and phosphorus removal. The obtained energy plants can be recycled as the raw materials for biogas to increase the production of biogas,which brings economic benefits while solving the environmental problems caused by piggery wastewater.

弱酸性蓝AS 染料排放的废盐制碳基吸附剂及利用

将染料弱酸性蓝AS(AS)生产排放的含盐废水喷雾干燥后制成废盐,再将其有机污染物煅烧制备成类活性炭吸附剂(LAC),用于AS染料生产过程中产生的洗涤废水的吸附脱色净化,同时回收粗盐NaCl可循环用于AS工业生产的盐析过程。对LAC进行吸附过程动力学、热力学研究,并研究AS染料废水溶液初始浓度、温度及pH对吸附性能的影响。在40 mg/L的AS染料废水中,温度为318 K的条件下,平衡吸附量为29.22 mg/g。在酸性及温度较高时吸附能力较强。Langmuir等温线方程能更好拟合吸附实验结果。另外,采用一锅混合法,添加四水合乙酸镁对LAC进行改性,改性后的吸附剂LACMg0.75比表面积较LAC提升了近5倍,饱和吸附量能够达到550.02 mg/g,较LAC提升了接近20倍。

合水油田含聚合物采出水处理技术的研究与应用

长庆合水油田采出水废水中含有大量的聚合物、水凝胶,采出水水体发黑、黏度大、乳化稳定性强、难破乳,难以用常规污水处理方法进行处理。在对水质成份进行详细分析后,认为水体发黑的原因是其中的二价铁离子与硫化物形成了黑色的硫化铁胶体固形物。用“氧化→解聚→絮凝”新工艺对合水油田采出水进行处理,效果十分显著。首先对含聚水中聚合物氧化解聚,破坏其结构稳定性,然后用适量的过碳酸钠(SPC)使硫化铁胶体脱色,随后再进行絮凝沉淀,使用200~350ppm的SPC和2~5ppm的阳离子聚丙烯酰胺和聚合硫酸铁组合的复合絮凝剂,可以使含聚采出水的悬浮物下降到30mg·L^(-1)以下,pH约为7.0,且有效降低了水体的色度和浊度,其中浊度降低率达到98.02%,铁离子去除率为96.46%。较好地解决了含聚废水水体发黑、不易沉降、难处理等问题,有效改善了采出水水质,达到回注要求。

电渗析技术在含盐工业废水处理中的应用研究进展

为了处理含盐工业废水的高盐污染问题,电渗析技术(electrodialysis)因其独特优点成为含盐工业废水脱盐的研究重点。介绍了填充床电渗析工艺、频繁倒电极电渗析工艺、双极膜电渗析工艺3种新型电渗析工艺,阐述了近几年电渗析技术在稀土工业废水、煤化工废水、锂提取加工和锂电池回收方面的应用。结果显示,3种新型电渗析工艺表现了较好的脱盐效能和资源回收能力;同时电渗析技术适用于稀土工业废水、煤化工废水脱盐处理及水资源回收利用,也能够应用于锂提取加工和锂电池回收。现阶段,电渗析技术在脱盐成本和脱盐性能方面还存在不足,因此电渗析技术需要与其他工艺进行耦合、优化电渗析技术的系统结构和工艺参数、优化离子交换膜来作为重点研究方向。

再生水回用对典型污水处理工艺生态效应的影响

再生水回用是降低水污染、改善水环境、提高水资源利用率的重要途径,但这一过程同步增加了药剂和能源的消耗,以及温室气体排放等。研究再生水回用对典型污水处理工艺的生态效应影响,可为污水处理策略的全过程优化提供支持。文中采用生命周期评价法,从元素资源消耗(ADPE)、化石燃料消耗(ADPF)、臭氧层耗竭(ODP)、全球变暖(GWP)、酸化(AP)、富营养化(EP)、淡水生态毒性(FAETP)、陆地生态毒性(TETP)和人类毒性(HTP)9种环境效应,对比分析了常规污水处理工艺AAO和再生水处理工艺AAO+MBR的生态效应。结果表明,AAO+MBR工艺对EP的削减效果是AAO工艺的1.1倍,污水处理效果优于单独使用厌氧/缺氧/好氧(AAO)工艺;AAO+膜生物反应器(MBR)工艺对ADPE、ADPF、ODP、GWP、AP、FAETP、TETP、HTP的负面影响均高于AAO工艺;进一步在20%、40%、60%、80%和100%不同再生水回用率情景下比较AAO工艺和AAO+MBR工艺对9种环境效应的影响,发现再生水回用率显著影响ADPE、ADPF、FAETP、ODP,当再生水回用率为100%时,对环境影响下降45%~100%;对AP、GWP、TETP、HTP的影响较小,当再生水回用率为100%时,对环境影响下降17%~25%;对EP影响则不显著,随着再生水回用率变化,EP基本保持不变。研究可为污水处理决策优化提供支持。

电场预处理对藻菌共生体处理养猪废水的影响机制分析

随着畜禽养殖业规模化集约化的发展,畜禽养殖废水已经成为了农业面源污染的主要来源,但其自身包含大量碳氮磷等营养元素又是重要的农业资源。针对养猪废水高色度浊度、高碳氮磷的特点,引入电场预处理来降低废水的色度、浊度,在促进藻菌共生体生长的同时提高废水中污染物的去除效率。结果表明:电场预处理能使养猪废水中的色度、浊度得到有效降低,铁、铝做阳极时色度、浊度的去除率均能达到90%以上。经电场预处理的废水在藻菌共生体的培养上也有更优的表现,铁、铝做阳极组中藻菌共生体对COD、TN、TP的7 d去除率分别为59.09%、61.78%、68.96%和62.26%、62.26%、83.92%,优于未经电场预处理组的47.82%、59.3%、60.48%。此外,铁、铝做阳极组和未经电场预处理组叶绿素含量分别从7.63、7.32、7.37 mg·L^(-1),增长到24.39、26.08、12.98 mg·L^(-1),是接种时的3.20、3.54、1.70倍,电场预处理明显提高了藻菌共生体中叶绿素的含量。说明电场预处理能有效提升藻菌共生体对污染物的去除效果,并获得更大的生物质资源,同步实现对废水的深度处理和资源利用。

连接自然与城市的资源循环工厂——宜兴城市污水资源概念厂

介绍宜兴城市污水资源概念厂的设计源起及过程,从整体设计出发,贯彻可持续设计,实现了理念上的开创性和引领性,技术上的先进性,成功打造了一座生态友好、资源循环、公众开放的现代概念工厂。

新型高效除氟剂在高盐含氟废水处理中的应用试验

废旧电池回收过程会产生大量高盐含氟废水,对生态环境和人体健康造成巨大威胁。试验采用新型高效除氟剂(型号NY-Z02)对高盐含氟废水进行除氟处理,确定最佳工艺条件。结果表明,最佳工艺条件下,反应温度为20℃,反应时间为20 min,除氟剂用量为1.2%,反应终点pH为7,除氟后废水氟含量为11.7 mg/L,除氟率为97.71%,废水磷含量为8.93 mg/L,除磷率为98.94%。除氟后,废水中氟和磷均符合排放标准,该试验结果可为高盐含氟废水的工业化处理提供理论依据。

工业水处理工艺优化与回用探讨

目前冶炼行业废水成分较为多样复杂,处理水的去向持续受到关注。文章介绍了某冶炼厂针对重金属离子的传统废水处理工艺以及改进后的废水处理工艺,并对当前存在的问题进行了分析,结合生产模式,提出了改进工艺的方法。结果表明:在当前生产条件下,不锈钢材质的设备更适用于生产废水处理回用。相比较水处理工艺1(污酸处理系统+深度处理系统),对水处理工艺2(化学法工艺)进行改进更为便利,且对提高循环水水质而言更高效便利,有利于促进废水的“零排放”,提高循环水质量。

再生聚酯制备用滤芯清洗系统技术改造

在再生聚酯的制备过程中,需要对滤芯进行批量清洗,在滤芯清洗时带来废水、废气的排放,造成严重的污染。文章介绍了将清洗的废水进行在线回收循环再利用,以及增加废气吸附吸收环节等技术改造方案和措施,将清洗废水通过无纺布进行过滤,再通过多级沉淀池进行沉淀、过滤、净化,达到使用标准。对技术改造实施前后的数据进行评估对比,每清洗一批60根滤芯可节约用水量约60吨,污水减排约60吨,降本增效、节能减排效果显著,取得了较好的经济效益。

高浓度废水处理及资源回收的研究

立足于废水有效治理和资源回收利用为一体的原则,采用减压蒸发结晶法处理印染厂实际生产产生的酸性废水,处理后废水可达标排放;利用溶剂萃取法回收结晶盐中所含产品,回收率为83.2%,实现了废水的净化处理和资源综合利用双重效益。

非均相臭氧催化氧化工艺深度处理煤化工废水

采用非均相臭氧催化氧化对陕西某化工有限责任公司煤化工废水进行深度处理,运行结果表明:氧化塔出水COD一直稳定在40 mg/L以下,COD去除率大于50%,出水色度值小于10,BOD/COD值由0.14~0.15提高至0.36~0.41,水质达到回用水标准,并且系统能够长时间连续稳定运行,说明对煤化工废水深度处理而言,非均相臭氧催化氧化是一种经济可行的工艺,该项目的成功实施和运行同时也为非均相臭氧催化氧化工艺在回用水领域的应用提供一定的参考价值。

聚酯生产废气废水的处理工艺研究

为了降低聚酯生产中所产生的废气和废水对环境的污染,本文以江苏某聚酯化纤企业为例,对处理废气废水的构筑物及设备进行研究,分析了废气废水处理系统的运行情况,并结合聚酯的生产流程及产污特点,制定出合适的废气废水处理方案,这些方案是使废气废水得到有效净化、提升聚酯生产环保性的重要举措。

船舶外板超高压水除锈过程中的末端污水处理关键技术研究

超高压水除锈是一种新型的环保工艺,主要解决船舶外板除锈、除漆。为了满足环保要求和做到除锈全过程管程,末端的污水处理是新工艺必须解决的问题。文章详细介绍了一种末端污水处理的技术,设计、研发真空设备及管道,从源头对污水进行收集,并通过应用一系列的污水处理装置,达到污水排放标准,满足环保要求。

净水厂生产废水回收再利用研究

挖掘净水厂生产废水的利用潜力,对其进行合理回用可节约淡水资源,同时具有保护环境的优点,有利于水资源的可持续发展。从安全性来考虑,生产废水处理后再回用是未来发展的必然趋势。生产废水处理方法中最常用的是混凝沉淀法,效果最好的是膜处理方法。膜处理法需控制好膜污染问题且成本偏高,随着膜构件价格逐渐降低,该技术将得到更广泛的应用。