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垃圾填埋场渗滤液处理工艺研究进展 总被引:1,自引:0,他引:1
介绍了垃圾渗滤液的来源和特点,结合近些年的工程实际和实验研究,主要综述了垃圾渗滤液的处理方案和技术,包括回灌法、土地处理法、物化法、生物法以及其他处理方法,在比较这些方法的基础上提出了一些建议。 相似文献
395.
分别采用7-乙氧基异酚恶唑酮.脱乙基酶(EROD)活性测定法,重组人激素受体基因的酵母测试和Q67发光菌试验方法,对北京市某生活污水处理厂的进水、二沉出水以及经过石灰法深度处理后的出水中的类二恶英物质、类雌激素物质和急性毒性物质进行了分析。进水中的三类生物毒性效应物质中的急性毒性物质,可通过活性污泥法基本去除,而对类雌激素物质和类二恶英物质的去除率分别为76%和52%。经过石灰沉淀法的深度处理后,可使上述两类物质的总去除率达到95%和68%。出水中的雌激素当量水平与欧洲国家污水处理厂出水水平相当,而类二恶英物质的总浓度低于美国EPA饮用水中二恶英的最大允许浓度。展示了生物毒性测试方法在排水生态风险和工艺评价方面的应用潜力。 相似文献
396.
The comparative toxicities of selected phenols to higher plants Cucumis sativus were measured and the negative logarithm molar concentration of the root elongation median inhibition (IRC50) were derived. Quantitative structure-activity relationships (QSARs) were developed to explore the toxicity influencing factors and for predictive purpose. The toxicity data, fell into two classes: polar narcosis and bio-reactive. For polar narcotic phenols, a highly significant two-parameter QSAR based on 1-octanol/water partition coefficient (logKow) and energy of the lowest unoccupied orbital (E(lumo)) was derived (IRC50 = 0.77 log Kow - 0.39E(lumo) + 2.36 n = 22 r2 = 0.89). The five bio-reactive chemicals proved to show elevated toxicity due to their typical substructure involved diverse reactive mechanisms. In an effort to model all chemicals, a robust multiple-variable QSAR combining logKow, E(lumo) and Qmax, the most negative net atomic charge, was developed (IRC50 = 0.65 logKow - 0.72E(lumo) + 0.23Qmax + 2.81 n = 27 r2 = 0.94), indicating that hydrophobicity, electrophilicity and hydrogen bond interaction contribute mainly to the phytotoxicity. The toxicological data was compared with Tetrahymena pyriformis 2-d population growth inhibition toxicity (IGC50) and excellent interspecies correlations were observed both for the polar narcotics and for five reactive chemicals (for polar narcotics: IRC50 = 0.95IGC50 + 1.07 n = 16 r2 = 0.89; for bio-reactive chemicals: IRC50 = 0.98IGC50 + 2.19 n = 5 r2 = 0.97; and for all: IRC50 = 0.93IGC50 + 1.63 n = 21 r2 = 0.87). This suggested that T pyriformis toxicity could serve as a surrogate of C. sativus toxicity for phenols and interspecies correlation also could be established for reactive chemicals. 相似文献
397.
The impacts of ultrafine airborne particles generated by diesel or gasoline engines on human lung cells have been investigated using a new in vitro cellular exposure technique. This technique enables direct deposition of the gasoline engine exhaust particles (GEP) and diesel engine exhaust particles (DEP) on human lung cells located at the air-cell interface on a transwell membrane in an exposure apparatus. The cellular responses to particle exposure were measured by the levels of IL-8 chemokines produced as a function of exposure time. The findings suggest that GEP and high-sulfur DEP induced the production of similar levels of IL-8 by unprimed A549 cells. The level of IL-8 produced by unprimed A549 cells in response to low-sulfur DEP was found lower than that produced in response to high-sulfur DEP and GEP. When cells were primed, simulating predisposed conditions, significant levels of IL-8 were produced. GEP triggered a much higher level of IL-8 production than DEP did. Furthermore, the time profile of IL-8 production induced by GEP was markedly different from that induced by DEP. The findings indicate that GEP could induce the production of higher levels of chemokines (i.e., IL-8) than DEP did, implying that exposure to GEP could be a greater health risk than exposure to DEP. 相似文献
398.
为了研究南京地区相对湿度对气溶胶的影响,利用位于南京信息工程大学的拉曼-瑞利-米氏激光雷达,分析湿度廓线对消光系数的影响;利用2014年3月~2015年2月国控点环境监测数据对可吸入颗粒物浓度特征进行统计,并与相对湿度进行逐月和四季对比分析,并计算各参数之间的相关系数,以期为南京市的城市布局与规划、大气污染治理等提供更多参考.结果表明,低空气溶胶的消光系数廓线与相对湿度廓线变化趋势高度一致,地面相对湿度与可吸入颗粒物浓度在一定湿度范围(以不发生重力沉降为界限)内,相对湿度越大越有利于颗粒物的形成,超过这个范围,相对湿度越大,颗粒物浓度越低,在南京地区,对于PM10来说,这个界限在40%~49%,对于PM2.5来说,这个界限在50%~59%. 相似文献
399.
In this study,direct contact membrane distillation(DCMD)was used for treating fermentation wastewater with high organic concentrations.DCMD performance characteristics including permeate flux,permeate water quality as well as membrane fouling were investigated systematically.Experimental results showed that,after 12 hr DCMD,the feed wastewater was concentrated by about a factor of 3.7 on a volumetric basis,with the permeate flux decreasing from the initial 8.7 L/m~2/hr to the final 4.3 L/m~2/hr due to membrane fouling;the protein concentration in the feed wastewater was increased by about 3.5 times and achieved a value of 6178 mg/L,which is suitable for reutilization.Although COD and TOC in permeate water increased continuously due to the transfer of volatile components from wastewater,organic rejection of over 95%was achieved in wastewater.GC–MS results suggested that the fermentation wastewater contained 128kinds of organics,in which 14 organics dominated.After 12 hr DCMD,not only volatile organics including trimethyl pyrazine,2-acetyl pyrrole,phenethyl alcohol and phenylacetic acid,but also non-volatile dibutyl phthalate was detected in permeate water due to membrane wetting.FT-IR and SEM–EDS results indicated that the deposits formed on the membrane inner surface mainly consisted of Ca,Mg,and amine,carboxylic acid and aromatic groups.The fouled membrane could be recovered,as most of the deposits could be removed using a HCl/Na OH chemical cleaning method. 相似文献
400.
测土配方施肥对油菜生产的影响——基于1 722份田间试验材料的经济学分析 总被引:1,自引:1,他引:0
论文基于1 722份田间试验数据,将氮、磷、钾肥的投入量和油菜的产出量分别折算为相应的具体投入值和产出值,首先,运用超越对数生产函数模型计算出各种化肥要素的边际产出,研究发现氮、磷、钾肥的投入对油菜产出值的作用大小存在一定差异,对油菜产出值的影响大小关系为氮肥>磷肥>钾肥,其中氮肥的产出弹性值为0.288 3,磷肥的产出弹性值为0.180 3,钾肥的产出弹性值为0.087 7。其次,继续探究氮、磷、钾肥在油菜生产中的相互关系,结果显示,氮肥替代弹性系数为-0.058 8,磷肥为0.120 9,钾肥为0.281 0。最后,测算出使油菜产出值最大的氮肥最佳投入值为951.20 元/hm2,最佳磷肥投入值为3 766.08 元/hm2,最佳钾肥投入值为621.32 元/hm2。 相似文献