窄脉冲电晕放电烟气脱硫产物粒径分析的实验研究

为了便于脱硫产物的收集和应用,用沉降法采样,用电子显微镜对产物气溶胶进行粒径分析．实验在窄脉冲电晕放电装置上,模拟含硫烟气在工况条件下（气体流量２ｍ３／ｈ,反应器入口处ＳＯ２浓度２０００ｍｌ／ｍ３,ＳＯ２和ＮＨ３在通道中停留时间为５ｓ以上,温度６０℃、水蒸气体积比７．５％,相对湿度３８．２％）进行．电子显微镜的观测结果显示,脱硫产物粉尘结构疏松,颗粒形状不规则．根据电镜照片的统计结果,得出产物粉尘的数目中位径ＮＭＤ为０．４０μｍ,几何标准偏差σ１＝５．２１;质量中位径ＭＭＤ为２．８２μｍ,几何标准偏差σ２＝１．４３     

热重分析技术研究石灰石脱硫特性

采用热重分析仪对徐州地区的贾汪、长山、铜山３种石灰石进行了脱硫反应试验,得到了石灰石品种、脱硫温度、ＳＯ２浓度和粒度等对ＣａＯ转化率的影响规律,同时,计算了化学反应速度常数Ｋ和反应速度系数ｂ。当粒度小于０．５ｍｍ时,Ｋ值范围是９．４×１０－４－２２×１０－４ｍ／ｓ;当粒度为０．５—１．０ｍｍ时,ｂ＝１２５４ｍｉｎ－１。当粒度为１．０—２．０ｍｍ时,ｂ＝１１０３ｍｉｎ－１。     

温度与湿度对氨为添加剂脉冲放电烟气脱硫的影响

对脉冲放电烟气脱硫的实验研究与理论分析表明,ＳＯ２的除主要取决于ＮＨ３与ＳＯ２热化学反应;在单位体积烟气注入能量为０－５Ｗ·ｈ／ｍ＾,脉冲放电使ＳＯ２脱率提高０－２５％,脱硫产物的主要组分是（ＮＨ２）２ＳＯ４,其含量随着单位体积烟气注入能量的增加而增大气光单位体积烟气注入能量为３Ｗ·ｈ／ｍ＾３,停留时间小于１０ｓ工业应用许可的范围内,烟气脱硫最佳温度为６０－６５℃,最佳含水体积分数为９－１１％。     

分析饮用水中五种卤代烃的顶空／气相色谱法验证

本文采用顶空／程序升温气相谱法快速分析饮用水中１．１－二氯乙烯，１．１．１．－三氯乙烷，１．１．２．－三氯乙烷，三溴甲烷１．１．２．２－四氯乙烷五种挥发性卤代烃，分离效果好，其相关系数均在０．９９以上，检出限分别为０．５０μｇ／ｌ．０．１０μｇ／ｌ。０．９８μｇ／ｌ，０．５６μｇ／ｌ，１．２０μｇ／ｌ，其回收率在８１．８％－１０２．７％之间，精密度在０．６２％－１２．１％之间。     

辽宁城镇居民饮用水总放射性水平调查

报道１９９０—１９９４年间对辽宁省５０个自来水公司及４０个厂矿自备水样品总α、总β放射性的调查结果。其总α范围分别在０．９×１０－２－１６．３×１０－２、０．３×１０－２－２１．６×１０－２Ｂｑ·Ｌ－１,均值分别为０．０４６、０．０６５Ｂｑ·Ｌ－１,超标率分别为８％。１５％。总β范围在０．０８—１．０７Ｂｑ·Ｌ－１,超标样品很少。研究表明,天然放射性核素是饮水中总α的主要贡献者,其中尤以天然铀贡献为最大,约占总α的４３％。     

用 Moss Bag 富集研究汞矿附近元素汞的沉降

应用ＭｏｓｓＢａｇ监测元素汞的干湿沉降．结果表明：矿区大气汞浓度２００—１１３５ｎｇ·ｍ－３时汞的湿沉降为１７００μｇ·ｍ－２·ａ－１;干沉降９８７μｇ·ｍ－２·ａ－１．而当距矿区６７ｋｍ,大气汞浓度３．４—４．０ｎｇ·ｍ－３时,其干沉降２１μｇ·ｍ－２·ａ－１,湿沉降３３μｇ·ｍ－２·ａ－１,湿沉降占总沉降６１％—６３％,干沉降占３７％—３９％,元素汞的干湿沉降与距汞源的距离明显相关     

贵州梵净山自然保护区大气汞的沉降

以铜仁汞矿为点源，研究对梵净山汞的辐射、沉降及流通影响．在海拔５００ｍ的梵净山定位测定，应用Ｍｏｓｂａｇ方法，评价梵净山Ｈｇ的干湿沉降的累积是１１５μｇ·ｍ－２·ａ－１，干沉降大约占总沉降的５０％，通过测定苔藓生物量和Ｈｇ含量估算Ｈｇ的总沉降量为８５０μｇ·ｍ－２·ａ－１，Ｈｇ的流通量平均为２１０μｇ·ｍ－２·ａ－１，Ｈｇ的总沉降占总流通量８０％．Ｈｇ在梵净山沉降累积随高度变化关系明显，海拔２０００ｍ以下时汞的沉降累积量较大，和苔藓植物指示汞含量变化关系相一致．     

钼（Ⅴ）—硫氰酸盐—次甲基蓝离子缔合物双波长分光光度法

本文研究了在聚乙烯醇存在下，于稀硫酸介质中．钼（Ｖ）与硫氰酸盐和次甲基蓝形成离子缔合物的双波长分光光度法。在２５ｍｌ容积中，０～１０μｇ吧钼遵守比耳定律，摩尔吸光系数为１．１８×１０｀６Ｌ·ｍｏｌ·ｃｍ￣（－１），Ｓａｎｄｅｌｌ灵敏度为８．０６×１０￣（－２）μｇ．ｃｍ￣（－２），方法已用于环境水中钼的测定，相对误差分别为—３．６５％和＋４．５６％，还用于人发中钼的测定，相对误差＋２．１３％。     

超滤法处理含乳化油废液

采用板框式超滤装置对钢管玫冷却用乳化油废液进行处理试验,结果表明,板框式超滤器在压力低于０．４０ＭＰａ,运行温度４０－４５℃条件下,配用ＰＳＦ超滤膜,可将乳化油废液一次连续浓缩,含油量由２％增至４０－５０％,体积２０倍,超滤平均通量５－２０Ｌ（ｍ＾２．ｈ）＾－１,渗透液中含油量降至１００ｍｇ．ｌ＾－１以下,油分截留率大于９９％,ＣＯＤ截留率大于９０％     

2,4—二氯苯基荧光酮与铬显色反应的研究与其应用

研究了铬（Ⅳ）－２，４－二氯苯基荧光酮（ＤＣＩＰＥ）－溴化十六烷基三甲胺（ＣＴＭＡＢ）体系的显色条件，试验结果表明，在ｐＨ５．２～７．０范围内，铬与ＤＣＩＰＦ及ＣＴＭＡＢ形成红色三元胶束配合物，其最大吸收波长为５７８ｎｍ，表现摩尔吸光系数为１．４０×１０＾５Ｉ．ｍｏｌ＾－１．ｃｍ＾－１，铬（Ⅵ）含量在０～９．０μｇ／２５ｍｌ范围内符合比耳定律，配合物的组成为Ｃｒ（Ⅵ）：ＤＣＩＰＦ＝１：２，拟定方法     

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.