步法制备乙酸酐新工艺

本文提出了一步法制备乙酸酐的新工艺，它具有工艺简单，反应快，转化率高等优点，是小批量生产乙酸酐的最佳方法。     

气相色谱法测定水中挥发酚

本文介绍气相色谱法测定水中的挥发酚。采用乙酸酐衍化预处理，氢火焰检测器(FID)测定，给出了方法的精密度和准确度，使用了质量控制(QC)样品来考察方法的性能，比较了色谱法与经典的4-AAP法的测定结果，     

加油站工艺设施问题分析与对策

加油站工艺设计和设施设备安装是加油站本质安全的重要要素。加油站油气回收工艺的规范性、符合性决定了加油站的正常合法经营。针对加油站工艺设施方面存在的问题,系统地分析了加油站工艺管道设计、工艺平面布置、工艺管道安装、设施设备安装等,以工艺设施安全和环保为出发点,提出加油站工艺设计对策思路和设施设备安装改进方案。     

港口水域污染治理工艺改进研究

提出一种新型的港口水域污染治理工艺,该工艺是对活性污泥工艺、生物膜工艺的改进,它将两种工艺的优点相结合,是一种复合工艺。研究分为三部分:首先对港口水域污染情况进行简要分析;其次对治理工艺进行改进;最后对工艺改进效果进行分析验证。结果表明:与活性污泥工艺、生物膜工艺相比,利用复合工艺治理水中五种主要污染物质后,悬浮物、BOD、COD、氨氮、其它的浓度较处理之前分别降低了1.14 mg/L~(-1)、3.08 mg/L~(-1)、0.79 mg/L~(-1)、1.89 mg/L~(-1)、0.3 mg/L~(-1),且降低幅度要比活性污泥工艺、生物膜工艺大得多;由此证明了该工艺改进效果。     

ASBR工艺的研究及应用

对厌氧序批式工艺(ASBR工艺)进行了系统分析。分析包括工艺过程、工艺特点、工艺的调控及在国内外的应用等。着重研究了该工艺的影响因素,如温度、碱度、进水时间与反应时间比、反应器尺寸等。分析研究表明,ASBR工艺是一种新型高效厌氧节能的工艺,有许多优点,具有广泛的应用前景,非常适合于处理我国复杂的废水水质。     

模糊层次分析法在保定市城镇污水处理技术综合评价中的应用

基于保定市城镇生活污水处理技术,采用改进的模糊层次分析法建立一个4层12个指标8种方案的综合评价体系,从经济、技术和管理等角度对氧化沟工艺、CASS工艺、UNITANK工艺、百乐克工艺、CAST工艺、A2/O与百乐克结合工艺、倒置A2/O工艺、A2/O工艺8种处理工艺进行综合评价。同时采用专家打分法对8种技术进行评价,结果表明CASS工艺的分值最高。     

废水生物脱氮除磷工艺技术经济比较分析

生物脱氮除磷工艺的选择,应根据实际情况经技术经济比较后确定。对A^2／O工艺、OCO工艺、CAST工艺、UNITANK工艺及BICT工艺进行了技术经济比较分析。认为在当今污水处理要求愈加严格的情况下,应优先选用高效能、低能耗、低投资及占地少、操作管理方便的处理工艺。     

城市污水处理厂污泥热干化工程工艺技术及关键设备介绍

城市污水处理厂脱水后污泥含水率一般在75%左右,生物污泥由于其成分复杂,污泥处置问题已成为解决现代城市污水处理厂产物的重难点问题。本文介绍了目前国内外较为常见的污泥热干化工艺设备,包括双桨叶式干化工艺、带式干化工艺、两段式组合干化工艺、流化床干化工艺、立式圆盘式干化工艺、转鼓式干化工艺、转盘式干化工艺。     

化学生物絮凝工艺处理城市污水比较研究

本文比较了化学生物絮凝工艺和化学絮凝工艺对城市污水的处理效果。试验结果为化学生物絮凝工艺的COD、TP、SS去除率为70％、74％、88％，化学絮凝工艺分别高出12％、12％、3％；污泥产量为4kg／d，相对化学絮凝工艺而言要少10％～15％。从而得出，化学生物絮凝工艺比化学絮凝工艺更适合处理城市污水。     

膜生物反应器工艺与常规和深度处理工艺处理长江原水比较

研究比较膜生物反应器(MBR)工艺与常规工艺和臭氧生物活性炭(O3-BAC)工艺处理长江原水的污染物去除效果。MBR工艺对浊度、UV254和CODMn的去除率分别达到96%、36%和32%,与常规工艺基本相当,弱于O3-BAC工艺。MBR工艺对氨氮去除率稍低于O3-BAC工艺,对挥发性有机毒物的去除效果却好于后者,常规工艺去除这2种污染物不理想。O3-BAC工艺出水加氯后消毒副产物生成量最少,仅有MBR工艺和常规工艺的70%,这表明O3-BAC工艺在减少加氯后消毒副产物的生成方面优势明显,同时也说明依靠MBR工艺的生物降解能力大幅减少消毒副产物生成的可行性不高。     

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.