Comprehensive treatment of latex wastewater and resource utilization of concentrated liquid

Latex wastewater is a kind of refractory organic wastewater containing high concentrations of organics and ammonia nitrogen.In this work,the combined process of forward osmosis(FO)and reverse osmosis(RO)was designed to treat the latex wastewater in the whole process,achieving the water recovery rate of 99%and basically no waste discharge after the catalytic oxidation process.The turbidity of the latex wastewater was decreased to below 1 NTU by microfiltration pretreatment,and then using MgCl_2 worked as the draw solution for FO process to treat the latex wastewater.Different operation conditions including adding acid or scale inhibitor as the pretreatment methods were conducted to improve the treatment performance of the combined process.After the treatment of the whole process,the concentration of COD was less than 20 mg·L^(-1),the concentration of NH_3-N was less than 10 mg·L^(-1),and the concentration of TP was less than 0.5 mg·L^(-1)for the treated latex wastewater.The water quality met standards of industrial water reuse after the complete analysis of the treated latex wastewater,meanwhile,useful substances of L-Quebrachitol(L-Q)were successfully extracted from the concentrated solution.Therefore,the combined process of FO and RO could realize the efficient treatment and reuse of latex wastewater,which provided with some important guidance on the industrial application.

Nanoscale Zero-Valent Iron(nZVI)for Heavy Metal Wastewater Treatment:A Perspective

Industries such as non-ferrous metal smelting discharge billions of gallons of highly toxic heavy metal wastewater(HMW)worldwide annually,posing a severe challenge to conventional wastewater treatment plants and harming the environment.HMW is traditionally treated via chemical precipitation using lime,caustic,or sulfide,but the effluents do not meet the increasingly stringent discharge standards.This issue has spurred an increase in research and the development of innovative treatment technologies,among which those using nanoparticles receive particular interest.Among such initiatives,treatment using nanoscale zero-valent iron(nZVI)is one of the best developed.While nZVI is already well known for its site-remediation use,this perspective highlights its application in HMW treatment with metal recovery.We demonstrate several advantages of nZVI in this wastewater application,including its multifunctionality in sequestrating a wide array of metal(loid)s(>30 species);its capability to capture and enrich metal(loid)s at low concentrations(with a removal capacity reaching 500 mg·g^(-1)nZVI);and its operational convenience due to its unique hydrodynamics.All these advantages are attributable to nZVI’s diminutive nanoparticle size and/or its unique iron chemistry.We also present the first engineering practice of this application,which has treated millions of cubic meters of HMW and recovered tons of valuable metals(e.g.,Cu and Au).It is concluded that nZVI is a potent reagent for treating HMW and that nZVI technology provides an eco-solution to this toxic waste.

Resourceful ecological treatment of wastewater in urban ecosystem

The treatment amount of wastewater is restricted to a small percentage in China. One of thereasons for that is the shortage of funds. Therefore , developing the technology of cost-effective , low energy-consuming and high efficiency is one of the important way to speed up the steps of wastewater treatment.This paper elucidated the principal and charactertics of the resourceful ecological treatment of wastewater. Asuccessful example of resourceful ecological land treatment of wastewater was given. The key points and therelative policies concerning the further development of resourceful ecological treatment of wastewater as asets of technologies have been suggested.

Water Resources Management and Wastewater Treatment in the Democratic Republic of Congo (D.R.C): Application of Galvanic Treatment, Results and Prospectives

The rapid industrial development and population growth increase the utilization of fresh water resulting in an increase of the amount of wastewater. Several Countries face a double challenge with regard to water resources, namely meeting the growing need for water for the population and treating the wastewater generated for application. The toxicity found in these water streams threatens the environment and human health. Hence the urgent need is to treat wastewater. The DRC is not immune from this threat. Its average population growth rate has exceeded the 3% and the number of industries it hosts continues to increase. The wastewater generated by this increasing pressure from urbanization and industrialization must be treated as required in the Congolese legal arsenal. Various factors need to be considered prior choosing the water treatment method. The choice must take into account the imperatives of the moment which are: modernization (local context) and sustainable development (international context). There are several wastewater treatments that are widely used for the removal of toxic elements such as ion exchange, reverse osmosis, chemical precipitation and electro-coagulation just to name a few. The most recent studies have shown that the galvanic technique can be used in the purification of water from domestic and industrial origin to meet drinking water standards. Various researchers have used this technique at laboratory and pilot scale demonstrating its cost-effectiveness as it uses no chemical reagents, consumes less energy and occupies only a small space for processing large flows. However, there are very few studies demonstrating the success of this treatment on an industrial scale. Therefore, this work seeks to understand and master the mechanisms that take place in the galvanic treatment. In addition, this study focuses on the development of a robust prototype that is adaptable to the needs of various users while at the same time being relatively cheap to meet the national needs.

Segregation Treatment and Resource Recycling of Enteric Coating and Heparin Sodium Manufacturing Wastewater

Firstly, the water-quality characteristics of intestinal lavage wastewater and enzymolysis wastewater from the typical heparin sodium pro- ductive process were analyzed, and then the segregation treatment was applied in the treatment of enteric coating and heparin sodium manufacturing wastewater. Finally, the treatment of the two kinds of wastewater by different methods were discussed. The results showed that, COD of enzymolysis wastewater treated by centrifugation-coagulation-Fenton reagent oxidation-adsorption process was lower than 100 mg/L, while intestinal lavage wastewater treated by coagulation-ASBR-SBR process could meet the first standard of Comprehensive Discharge Standard of Sewage （GB8978-1996） after one month of continuous operation.

Resourceful Utilization of Tannery Wastewater

Leather industry is an important light industry in China.Leather making requires a series of chemical treatment.Degreasing,unhairing and chrome tanning wastewaters are the main portions of tannery wastewater.Reclaiming and reusing these wastewaters can eliminate 80% of COD,75% of BOD,95% of chromium and 93% of sulfuret,furthermore reduce environment impact,decrease treatment costs,save chemicals and water.Some application methods of wastewater reclamation and reuse for different operations were reported.The suitable reclamation and reuse technologies can enable leather making processes more rational,and realize the recovery and recycle of several chemicals in the tannery.Resourceful utilization of tannery wastewater should mate with renovating production technology,updating equipment,and must be guaranteed sufficiently by environmental protection measures.

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).

Water shortage and wastewater reuse

China is not abandantly supplied with freshwater. Water shortage is a crucial problem in northern China, and affects the development of economy and causes a host of environmental and ecological problems. Water saving, water resource protection, strengthening of management and exploitation of new water resources are some of the major measures for solving the water shortage problem. Wastewater reuse is also a feasible and practical means of alleviating the problem.

Reclamation and reuse of distributed wastewater and programming based on cost analysis

In order to improve the water environment of Songhua River,develop and maintain a healthy water cycle,the article has made theoretical and mathematical analyses of wastewater treatment and reuse.It proposes that the important link of sustainable utilization of urban water resources is wastewater treatment and reuse,and the main approach of sustainable utilization of water resources is water saving,wastewater reclamation and reuse.Through establishing the cost equation of recycle water system and optimizing it by Matlab,an optimal treatment scale of the city recycle distributed wastewater system is obtained.The principles of recycle water system in northern areas are put forward based on the research of sustainable utilization of water resource in Songbei district.The results can provide experiences and references for water saving,wastewater reclamation and reuse in northern cities of China.

Evaluation of the exploitation of nontraditional water resources—Case study of Yantian District in Shenzhen

Yantian District in Shenzhen is a water deficient area. Water shortage has become a major obstacle to its further economic progress. Consequently, rational exploitation of nontraditional water resources(NWR)has been naturally adopted to increase local available water volume. The purpose of this paper is to analyse the exploitation of two kinds of NWR, namely wastewater reuse and seawater utilization, in Yantian District, and assess the contribution of each mode to deal with the water crisis. Two different nontraditional water supply systems respectively based on the reclaimed water and sea water were presented, and the effects of each system were evaluated in terms of technology, economy and environment. The result shows that both wastewater reclamation and reuse (WRR) and direct utilization of seawater (DUS) are of great importance to cope with the tight water resource situation in the district. The data indicate that the fresh water saved by WRR system and DUS system is 29 and 17 million m3/a respectively. Moreover, the BOD, COD, NH3-N and T-P reduced by the WRR system are 870, 2900, 725 and 87 t/a, respectively. Considering the integrated effectiveness, the development of WRR system, which is of specific significance to exploiting new water resource and save natural fresh water supplied from distant water diversion project, is the preferred methods used to solve the water shortage problem in Yantian District and recover the water environment as well as maintain the sustainable development of the city zone.

Experimental Model to Treat BOD5, COD in Wastewater by Eichhornia Crassipes Raft, and Propose a Plan to Restore Water Source of To Lich River, Hanoi, Vietnam

This paper presents the results of studies on evaluating the effectiveness of wastewater treatment by Eichhornia crassipes raft, the influent is the water of To Lich river. This study was conducted 3 times with 3 different velocity （0.037 m/s, 0.0099 m/s and 0.0126m/s） in the tank of eichhornia crassipes. Each time took 04 water samples for analysis at 4 locations： the influent source and 3 points at a distance of 4.0 m, 8.0 m and 12.0 m from the influent. Based on the experimental results, it proposes the size, number and type of raft to control the growth of eichhomia crassipes and treat the sewage of To Lich river to meet the Vietnamese Water Standard QCVN 08 （cohmm A2, B 1） and combine ecological landscaping.

马铃薯淀粉废水处理现状及资源化利用

针对马铃薯淀粉废水的来源、性质及特点,总结了目前马铃薯淀粉废水的处理技术如物化法、生物法和综合处理法,以及资源化利用途径包括马铃薯蛋白的回收利用、生产单细胞蛋白、生产微生物絮凝剂和生产新能源等,并提出开发高效、资源化、绿色可持续的马铃薯淀粉废水物化处理技术的展望,以此为马铃薯淀粉废水未来研究方向提供参考。

光合微生物在畜禽养殖废水资源化处理中的研究进展

畜禽养殖废水成分复杂,具有污染物种类多和浓度高的特点。目前对畜禽养殖废水的处理方式已由传统的处理技术逐渐向资源化技术转移。鉴于畜禽养殖废水的水质特点和资源回收潜力,基于光合微生物的处理技术成为传统废水处理技术的一种成本效益高的极具潜力的替代方法。介绍了畜禽养殖废水的特点和资源化处理趋势,分析了传统处理技术的局限,并比较了传统处理技术与基于光合微生物的处理技术的优劣。从微藻和光合细菌两类光合微生物的角度解释了基于光合微生物的处理技术的作用原理。此外,还讨论了光合微生物技术在畜禽养殖废水处理中的几种复合处理技术,以及其可生产的生物燃料、生物塑料、生物饲料等增值产品。最后,提出了未来光合微生物处理技术应朝着规模扩大化、适用环境自然化、附加产品价值具体化的方向发展。

磷酸铁废水零排放及资源化处理技术分析

目前,磷酸铁锂是锂电池的主要正极材料,而磷酸铁是制备磷酸铁锂的关键前驱体。磷酸铁生产过程产生大量废水,其酸性强、盐分高,处理难度大,现已成为制约磷酸铁生产企业发展的瓶颈。磷酸铁废水含有高浓度磷酸根、硫酸根、氨根及金属离子,废水经预处理+膜浓缩+蒸发结晶处理后可获得硫酸铵、磷酸二氢铵等副产品,处理后的废水可回用于生产环节,因而磷酸铁废水具有良好的资源化回收价值。本文综述磷酸铁废水处理技术现状,分析磷酸铁废水处理存在的问题,然后提出磷酸铁废水零排放处理技术思路,以实现磷酸铁废水的资源化利用,保护生态环境。

焦化尾水资源化回用集成工艺中试

为实现焦化尾水的资源化回用,开发了以预处理、压力-电驱动膜组合及双极膜电渗析技术为核心的集成工艺,并进行了中试研究。集成工艺中,化学软化和臭氧-双氧水复合氧化工艺用于去除原水中的硬度和反渗透浓水中的难降解有机物,纳滤工艺完成了一价离子与高价离子的分离,电渗析和双极膜电渗析工艺实现了焦化尾水的近零排放和酸碱资源再生。化学软化工艺对原水的硬度去除率可达64.2%;臭氧-双氧水复合氧化工艺对反渗透浓水的COD去除率可达35.0%;纳滤工艺的脱盐率可达30.2%,对氯离子、硫酸根、硬度和TOC去除率分别可达-6.8%、97.3%、78.4%和87.4%;双极膜电渗析工艺可得浓度均为2 mol/L以上的酸和碱,能耗为4.0 kW·h/kg。该集成工艺的水回用率大于90%,酸碱可短程循环利用。

肝素钠生产废水对小球藻生长和营养物去除的影响

肝素钠生产废水含有丰富的营养物,是潜在的微藻培养基。为探究其培养微藻的可行性,利用不同体积分数(10%~40%)肝素钠生产废水培养3株索罗金小球藻Chlorellasorokiniana(编号GT1、XY3-3、CMBB276),筛选出高耐受性的藻株CMBB276。探究该藻株在不同体积分数肝素钠生产废水中生长时的营养物去除过程、生化组成以及热值等参数变化,以期筛选出最适废水体积分数。结果表明,随着废水体积分数增加,藻株CMBB276的最高细胞密度、总氮(TN)去除率、碳水化合物和脂肪酸质量分数、蛋白质产率逐渐降低,而总有机碳(TOC)与TN去除速率以及蛋白质质量分数逐渐增加,TOC去除率和热值基本保持不变。最终确定最适废水体积分数为20%,培养结束时藻株CMBB276的细胞密度为6.4×10^(7)个/mL,TOC和TN去除率分别为83.3%和63.0%,蛋白质质量分数及产率为52.5%和22.22 mg/(L·d),热值为20.37 MJ/kg。因此,利用适宜体积分数的肝素钠生产废水培养小球藻能高效净化肝素钠生产废水中的TOC和TN;同时,废水培养的藻株CMBB276具有高蛋白质和热值等特征,在资源化利用方面极具潜力。

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。

高含酚废水的资源化处理技术研究进展

我国将高含酚废水列为水污染控制中重点解决的有害废水之一,其中富含大量挥发性和不挥发性酚类物质。由于酚类物质难以降解且具有较高毒性,对环境和人体都带来巨大危害。苯酚及其他酚类化合物作为重要的精细化工原料广泛应用于各种化学工业生产领域。因此,对高含酚废水进行有效处理对于化学工业生产具有重要意义。本文综述了国内外关于高含酚废水资源化处理技术的研究进展,并简要分析了各种方法的优缺点,并对其未来发展进行了展望。

电化学-膜生物反应器强化污废水处理的研究进展

电化学耦合膜生物反应器(EMBR)是新兴的污废水处理技术,除了能够高效去除常规污染物,EMBR在去除微污染物和病原微生物、缓解抗生素抗性基因增殖、控制膜污染和回收生物能源与资源等方面也具有显著的优势。综述了EMBR工艺的原理及特点、污废水处理效能、能源与资源回收效果、膜污染控制和技术挑战。为了推动EMBR的工程应用,未来仍需开发具有高导电性、生物相容性的电极材料,优化反应器构型和操作条件,以持续提升对污废水的处理效能。

农村生活污水资源化利用技术模式及工程示范

文中通过对农村生活污水治理问题的分析,探讨了农村生活污水资源化利用的必要性与可行性,提出了资源化利用中应遵循因地制宜、以用促治、经济合理、生态安全的原则,归纳总结了农村生活污水资源化利用的灌溉利用、生态消纳和分散就地利用3种技术模式。通过工程应用示范的方式,分析了3种模式的适用范围:(1)灌溉利用适用于300 m范围内有农田、林地、草地;(2)生态消纳适用于附近有可利用的坑塘、湿地或有可新建条件;(3)分散就地利用适用于农户分散且房前屋后有“四小园”。同时,分析了3种利用模式的户均养护成本,分散就地利用更加经济合理。资源化利用3种模式的推广,将更加有利于农村生活污水治理降本增效。