利用烟道气处理焦化剩余氨水技术

利用淮钢发电厂锅炉烟道气处理焦化剩余氨水 ,不仅实现了焦化剩余氨水零排放 ,并具有脱硫降尘的效果。     

焦化废水处理技术的重大突破

日前，国家冶金局、国家环境保护总局等单位在淮阴钢铁集团公司组织召开了该公司利用烟道气处理剩余氨水的技术鉴定会。与会同志在运行现场看到，生产过程中产生的锅炉烟气变成淡淡气雾，排放的具有浓烈异味的黑褐色焦化废水瞬间“无影无踪”。国家环境保护总局气检中。心和淮阴市环境保护监测中心站监测表明，不仅废水实现零排放，各项烟气指标也全部达到国家大气污染物综合排放标准要求。这项“以废治废”的科研成果每年可为淮阴钢铁集团公司节约资金85万元。焦化废水的脱氮问题一直为国内外所关注。长期以来，焦化废水处理主要依赖于普通…     

焦化废水中有害物质的回收及破坏处理

对焦化厂废水的综合治理进行了讨论，介绍了当前几种先进有效的治理技术。生化处理法需对焦化废水中高浓度的酚、氰、氨先回收利用，之后与其它有害物含量较低的废水汇合进行破坏性处理；催化湿式氧化法净化效率高，流程简单；烟道气治理焦化废水可实现以废治废的目的。     

利用燃煤锅炉烟道气处理工业废水的理论与实践

阐述了燃煤锅炉烟道气的主要化学成分及处理废水的机理 ,介绍了锅炉烟道气处理废水的研究与应用     

焦化废水中几种典型难降解有机物的特性研究及处理技术

介绍了焦化废水中吲哚，吡啶，喹啉三种典型难降解有机物的物理的物理化学性质，研究了这三种典型难解有机物的处理特性，简要介绍了几种选进有效的焦化废水的处理技术，总结了处理焦化废水中针对难降解有机物应注意的技术对策。     

焦化废水的微生物降解研究进展

焦化废水的成分十分复杂，除含苯系物外，还含有多芳香烃和杂环类有机物，研究表明，选择适合的微生物，并采用相应的生物反应器及处理工艺，可有效地除焦化废水中的COD和其他有毒化合物，文章从降解焦化废水的微生物种类，生物降解原理，降解方法，生物反应器及工艺流程等方面，阐述了焦化废水微生物降解的最新研究进展，指出了焦化废水微生物处理需进一步解决的问题。     

降低煤气吹脱解吸剩余氨水中碱耗量的研究

针对目前煤气吹脱解吸法处理焦化剩余氨水的过程中,碱的耗量较高的现状,结合具有专利技术的复合解吸塔,通过现场中试试验,研究了增加保温装置,改变加碱的位置,并适当增加了废水的停留时间的影响。最佳操作条件为:中位加碱,吹脱次数n=3,煤气温度T g=70℃,废水温度T w=90℃,pH=11,表面活性剂加入量ρ=10 mg/L,气液比q=350∶1,处理后的废水氨氮含量为248.2 mg/L,氨氮去除率可达到92.75%。最终的碱耗量为5.9 kg/m3,比原来的碱耗量降低了46.36%。     

焦化废水生化处理研究新进展

焦化废水是炼焦、煤气净化及焦化产品回收过程中产生的废水。总结了近几年焦化废水生化处理技术与工艺及其影响因素,并结合近年来环境生物技术的前沿,提出了焦化废水生化处理技术的发展方向。     

A1-A2-O生物法处理焦化废水

焦化废水属于高毒物质,其中的大部分多环芳烃都具有"三致作用"。为保护生态环境,焦化废水必须进行无害化处理。阐述了焦化废水的生物危害性及生态毒性效应,分析了处理焦化废水的A1-A2-O生物法,并分别对焦化废水中有机污染物的生物去除规律,难降解持久性有机污染物在生物污泥相中的吸附累积效应,焦化废水生物处理技术的生物学原理进行了归纳和总结。     

浅谈焦化废水的处理

焦化废水是一种典型的含难降解有机污染物的工业废水,除含酚类化合物外,还含有多种芳香烃和杂环类有机物,成分复杂,水量大,对环境污染严重。因此,焦化废水的处理越来越多的受到相关学者及专家的重视。本文首先从焦化废水的来源及特征出发,根据其特殊性,综合阐述了近年来国内外焦化废水的常规处理方法及深度处理方法,为以后焦化废水的处理提供一些思路。     

Distribution and ecological effect of mercury in Laogang landfill, Shanghai, China

Laogang landfill near Shanghai is the largest landfill in China, and receives about 10000 t of daily garbage per day, Samples of topsoil and plants were analyzed to evaluate mercury pollution from the landfill. For topsoil samples, there were significant correlations among total mercury （HgT）, combinative mercury （Hgc） and gaseous mercury （HgG）, and content of total organic carbon （TOC）, but, no significantly relationship was found between Hg content and filling time. Hg content changes in vertical profiles with time showed that the average Hgv of profiles 1992, 1996, and 2000 was similar, but their average HgG was quite different. HgT was significantly correlated with Hgc in profile 1992 and 2000, and Hgv was significantly correlated with Hg6 in profile 1996. HgG/Hgv ratio in profile samples decreased in the order of （HgG,/HgT）1992〉（HgG/HgT）1996〉〉（HgG/HgT）2000. A simple outline of Hg release in landfill could be drawn： with increasing of filling time, degradation undergoes different biodegradation, accordingly, gaseous mercury goes through small, more, and small proportion to total mercury. Distribution of Hg in plants was inhomogeneous, following the order of leaf〉root〉stem. The highest value of leaf may be associated with higher atmospheric Hg from landfill. Ligneous plants （e.g. Phyllostachys glanca, Prunus salicina and Ligustrum lucidum） are capable of enriching more Hg than herbaceous plants.     

EDTA-enhanced phytoremediation of lead contaminated soil by Bidens maximowicziana

Phytoremediation is a potential cleanup technology for the removal of heavy metals from contaminated soils.Bidens maximowicziana is a new Pb hyperaccumulator,which not only has remarkable tolerance to Pb but also extraordinary accumulation capacity for Pb.The maximum Pb concentration was 1509.3 mg/kg in roots and 2164.7 mg/kg in overground tissues.The Pb distribution order in the B. maximowicziana was:leaf>stem>root.The effect of amendments on phytoremediation was also studied.The mobility of soil Pb and the Pb concentrations in plants were both increased by EDTA application.Compared with CK(control check),EDTA application promoted translocation of Pb to overground parts of the plant.The Pb concentrations in overground parts of plants was increased from 24.23-680.56 mg/kg to 29.07-1905.57 mg/kg.This research demonstrated that B.maximowicziana appeared to be suitable for phytoremediation of Pb contaminated soil,especially,combination with EDTA.     

Decomposition of alachlor by ozonation and its mechanism

Decomposition and corresponding mechanism of alachlor, an endocrine disruptor in water by ozonation were investigated. Results showed that alachlor could not be completely mineralized by ozone alone. Many intermediates and final products were formed during the process, including aromatic compounds, aliphatic carboxylic acids, and inorganic ions. In evoluting these products, some of them with weak polarity were qualitatively identified by GC-MS. The information of inorganic ions suggested that the dechlorination was the first and the fastest step in the ozonation of alachlor.     

Enzymatic oxidation of aqueous pentachlorophenol

The influence of the nonionic surfactant Tween 80 on pentachlorophenol （PCP） oxidation catalyzed by horseradish peroxidase was studied. The surfactant was tested at concentrations below and above its critical micelle concentration （CMC）. Enhancement of PCP removal was observed at sub-CMCs. The presence of Tween 80 in the reaction mixture reduced enzyme inactivation which occurred through a combination of free radical attack and sorption by precipitated products. A simple first-order model was able to simulate time profiles for enzyme inactivation in the presence or absence of Tween 80. At supra-CMCs, the surfactant caused noticeable reductions in PCP removal, presumably through micelle partitioning of PCP which precluded the hydrophobic PCP molecule from interacting with the enzyme.     

基于综合水质标识指数和对应分析法的校园河道水质评价

以三峡大学的校园河道求索溪为研究对象,利用综合水质标识指数法确定求索溪水质类别,分析其水质时空变化规律,并利用对应分析法得出求索溪中不同监测点的主要污染因子.研究结果表明:求索溪整体的综合水质标识指数为7.423,整体水质为劣V类(地表水环境质量标准GB 3838-2002)且黑臭.从时间变化来看,求索溪4月份的水质最差,5月份次之,4、5月份所有监测点的水质都劣于V类且黑臭;8月份水质最好,水质为Ⅳ类;从空间分布来看,8个监测点综合水质标识指数均超过6.0,水质为劣V类,其中6号监测点的水质相对最好,监测点3号的水质相对最差;对应分析法得出求索溪的整体水体污染程度受总氮因子的影响最大,其次为总磷.该研究拟为求索溪及类似校园河道的水环境治理研究提供基础依据和参考.     

Effects of chitosan on growth of an aquatic plant (Hydrilla verticillata) in polluted waters with different chemical oxygen demands

Effects of chitosan on a submersed plant, Hydrilla verticillata, were investigated. Results indicated that H. venicillata could prevent ultrastructure phytotoxicities and oxidativereaction from polluted water with high chemical oxygen demand (COD). Superoxide dismutase (SOD) activity and malondialdehyde (MDA) contents in H. verticillata treated with 0.1% chitosan in wastewater increased with high COD (980 mg/L) and decreased with low COD (63 mg/L), respectively. Ultrastructural analysis showed that the stroma and grana of chloroplast basically remained normal. However, plant cells from the control experiment (untreated with chitosan) were vacuolated and the cell interval increased. The relict of protoplast moved to the center, with cells tending to disjoint. Our findings indicate that wastewater with high COD concentration can cause a substantial damage to submersed plant, nevertheless, chitosan probably could alleviate the membrane lipid peroxidization and ultrastructure phytotoxicities, and protect plant cells from stress of high COD concentration polluted water.     

Removal of cadmium using MnO2 loaded D301 resin

MnO2 loaded weak basic anion exchange resin D301 （Anion exchange resin, macroreticular weak basic styrene） as adsorbent has been prepared and applied to the removal of cadmium. The adsorption characteristics have been investigated with respect to effect of pH, equilibrium isotherms, removal kinetic data, and interference of the coexisting ions. The results indicated that the Cd^2＋ could be efficiently removed using MnO2 loaded D301 resin in the pH range of 3-8 from aqueous solutions with the co-existence of high concentration of alkali and alkaline-earth metals ions. The saturate adsorption capacity of the Cd^2＋ was 77.88 mg/g. The adsorption process followed the pseudo first-order kinetics. The equilibrium data obtained in this study accorded excellently with the Langmuir adsorption isotherm.     

Evaluation of phytoextracting cadmium and lead by sunflower, ricinus, alfalfa and mustard in hydroponic culture

Soil contaminated with heavy metals cadmium(Cd)and lead(Pb)is hard to be remediated.Phytoremediation may be a feasible method to remove toxic metals from soil,but there are few suitable plants which can hyperaccumulate metals.In this study,Cd and Pb accumulation by four plants including sunflower(Helianthus annuus L.),mustard(Brassica juncea L.),alfalfa(Medicago sativa L.), ricinus(Ricinus communis L.)in hydroponic cultures was compared.Results showed that these plants could phytocxtract heavy metals, the ability of accumulation differed with species,concentrations and categories of heavy metals.Values of BCF(bioconcentration factor)and TF(translocation factor)indicated that four species had dissimilar abilities of phytoextraction and transportation of heavy metals.Changes on the biomass of plants,pH and Eh at different treatments revealed that these four plants had distinct responses to Cd and Pb in cultures.Measurements should be taken to improve the phytoremediation of sites contaminated with heavy metals,such as pH and Eh regulations,and so forth.     

Effect of coagulation pretreatment on the fouling of ultrafiltration membrane

The purpose of this study is to understand the effect and mechanism of preventing membrane fouling, by coagulation pretreatment, in terms of fractional component and molecular weight of natural organic matter （NOM）. A relatively higher molecular weight （MW） of hydrophobic compounds was responsible for a rapid decline in the ultrafiltration flux. Coagulation could effectively remove the hydrophobic organics, resulting in the increase of flux. It was found that a lower MW of neutral hydrophilic compounds, which could remove inadequately by coagulation, was responsible for the slow declining flux. The fluxes in the filtration of coagulated water and supernatant water were compared and the results showed that a lower MW of neutral hydrophilic compounds remained in the supernatant water after coagulation could be rejected by a membrane, resulting in fouling. It was also found that the coagulated flocs could absorb neutral hydrophilic compounds effectively. Therefore, with the coagulated flocs formed on the membrane surface, the flux decline could be improved.     

Penetration analysis of elements and bioleaching treatment of spent refractory for recycling

Acidithiobacillus ferrooxidans ATCC23270 and Acidithiobacillus thiooxidans TM-32 were used for bioleaching of spent refractories of aluminium and copper melting furnaces for their recycling.Firstly,penetration of elements into aluminium melting furnace refractory was investigated and it was found that up to 7 cm from surface was contaminated.Comparison on leaching efficiency by the strains ATCC23270 and TM-32 found that the strain ATCC23270 could treat larger amount of the refractories than the strain TM-32 could do.In the experiment of bioleaching of spent refractory aluminium melting furnace by the strain ATCC23270,high leaching efficiency were obtained on Al,Si,and Ca,and extremely low leaching performance was,however,shown on the rest of elements i.e.,Na,Mn,and Zn.Under the strain TM-32 use,relatively high leaching performance was recognized on Al,Si,Ca,Na,Mn,and Zn.In the experiment of bioleaching for spent refractory copper melting furnace,almost the same leaching trends were shown on Cu,Zn,Al,and Si under the strains ACTT23270 and TM-32 uses.