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321.
石油污染土壤综合修复治理方法研究 总被引:1,自引:1,他引:0
通过对石油污染土壤情况调查发现,石油污染土壤程度在平面上,以油井为中心,污染程度向四周减轻;在纵深上,土壤表层污染较重,往下随深度递增而呈减轻的趋势。因此,基于土壤污染程度分布情况,各区域的治理方法也不同,污染土壤严重区域(油井附近)采用土壤置换法,轻微区域(外围)采用植物修复技术,中等区域(介于前两者之间)采用微生物修复技术。为了提高综合修复质量,在中等和轻微污染区域进行微生物+植物联合修复技术试验,结合试验效果,合理利用该技术最终可达到治理目的。 相似文献
322.
水生态环境中硝酸盐异化还原过程反硝化、厌氧氨氧化和硝酸盐异化还原成铵(DNRA),对氮循环起着重要作用.采用泥浆培养实验,并结合15N同位素示踪技术对长江口青草沙水库沉积物硝酸盐异化还原过程的温度敏感性及影响因子进行了研究.结果表明,原位温度10℃时沉积物中反硝化、厌氧氨氧化和DNRA速率分别是0.18~6.86、0.26~3.16和0.09~0.25μmol N/(kg·h).当培养温度升高到20℃和30℃时,反硝化速率分别是0.43~6.22和0.68~6.56μmol N/(kg·h),平均比10℃时升高了15.7%和21.6%;厌氧氨氧化速率分别是0.61~3.2和0.77~3.54μmol N/(kg·h),平均比10℃时升高了27.8%和42.6%;DNRA速率分别是0.09~0.23和0.1~0.18μmol N/(kg·h),均比10℃时降低了4.2%.沉积物厌氧氨氧化对温度最为敏感,其次是反硝化,均随温度升高而增大;而DNRA最不敏感,随温度升高而减小.相关性分析结果发现有机碳、氨氮、二价铁和硫化物是影响硝酸盐异化还原的主要环境因子.反硝化和厌氧氨氧化硝酸盐还原的贡献分别是34%~71%和28%~49%,而DNRA为2%~17%.青草沙水库沉积物反硝化和厌氧氨氧化过程每年可去除活性氮大约为3.25×103t和1.68×103t,约占库区输入氮的54.17%. 相似文献
323.
Jun QIAO Chengdong ZHANG Shuiming LUO Wei CHEN 《Frontiers of Environmental Science & Engineering》2014,8(2):293-304
This study evaluated the effectiveness of different amendments--including a commercial NPK fertilizer, a humic substance (HS), an organic industrial waste (NovoGro), and a yeast-bacteria consortium--in the remediation of highly contaminated (up to 6% of total petroleum hydrocarbons) oilfield soils. The concentrations of hydrocarbon, soil toxicity, physicochemical properties of the soil, microbial population numbers, enzyme activities and microbial community structures were examined during the 90-d incubation. The results showed that the greatest degradation of total petroleum hydro- carbons (TPH) was observed with the biostimulation using mixture of NPK, HS and NovoGro, a treatment scheme that enhanced both dehydrogenase and lipase activities in soil. Introduction of exogenous hydrocarbon-degrading bacteria (in addition to biostimulation with NPK, HS and NovoGro) had negligible effect on the removal of TPH, which was likely due to the competition between exogenous and autochthonous microorganisms. None- theless, the addition of exogenous yeast-bacteria consor- tium significantly enhanced the removal of the aromatic fraction of the petroleum hydrocarbons, thus detoxifying the soil. The effect of bioaugmentation on the removal of more recalcitrant petroleum hydrocarbon fraction was likely due to the synergistic effect of bacteria and fungi. 相似文献
324.
根据珠三角地区典型工业行业VOCs治理技术应用情况调研数据,选取6种典型治理技术开展现场测试,比较各类技术对VOCs的去除率和对VOCs物种的去除特征. 结果表明:活性炭吸附、水喷淋+活性炭吸附、活性炭吸附浓缩+催化燃烧、低温等离子体、溶液吸收、水喷淋+溶液吸收6种技术对工业VOCs去除率的范围分别为-98.1%~79.2%(负值表示可能存在活性炭脱附作用,下同)、-167.4%~57.5%、-3.8%~66.5%、34.1%~96.3%、22.8%~43.1%和2.7%~19.6%. 活性炭吸附及其组合技术对ρ(VOCs)<100 mg/m3的废气处理效果很差;而低温等离子体对ρ(VOCs)>1 000 mg/m3的废气治理效果较差. 活性炭吸附及其组合治理技术对芳香烃、酯类和醚类的去除率一般在40.0%左右;低温等离子体对除卤代烃外的其他物种去除率在28.6%~74.6%之间;溶液吸收法对醚类、芳香烃、酯类和卤代烃的去除率达33.2%~90.1%,而水喷淋+溶液吸收法对醇类、酮类和醚类的去除率可达到41.8%~98.9%. 未来应从经济、技术、监管三方面对工业VOCs治理技术进行综合评估,同时应对更多工业源的VOCs治理技术开展实测评估. 相似文献
325.
326.
农业利用有机废弃物的生态工程 总被引:8,自引:0,他引:8
本文运用生态工程将农业利用有机废弃的主要用途划分为作饲料,肥料,能源,培养料和多层次循环利用5种方式,论述了中国农业利用有机废弃物的历史,现状与水平,对农业利用作秸秆,畜禽粪便,沼气发酵余物和机的主要秣工程技术。 相似文献
327.
Hagenah E 《Environmental pollution (Barking, Essex : 1987)》1999,100(1-3):13-18
A lot of scientific knowledge is required to carry out and enforce environmental regulations. The paper deals with the relationship between law and science from a legal perspective. First, some difficulties in using science to carry out environmental regulations are outlined. After this, some legal concepts which try to cope with the problems are presented. Aspects discussed are the precautionary principle, the legal concept of 'state of the art', general standard setting, the flexibility of the regulations, and procedural regulations for the standard-setting process. Finally, the new challenge for science that derives from the legal demand of an integrated approach to environmental protection is addressed. 相似文献
328.
ABSTRACT. Society has long sought to maximize the welfare of its members by allocating its limited resources so as to provide maximum satisfaction. As long as all of the values that society gains or loses are measured in the market place in terms of price, the process of maximizing through economic models is relatively straightforward. In fact, however, the total value that society receives from the use of its resources is not completely measured through the private market transactions. There are some values created which are external to the market system. The resulting underinvestment in natural resources by the private sector necessitates the entry of the public sector. The presence of intangible benefits and intangible costs has long been recognized, but completely satisfactory methods for including these in the quantitative analysis of benefit-cost have not been developed. Some progress has been made in including recreational values in project analysis via the expenditures method, the Gross National Product method, consumer surplus method, cost method, market value method, and monopoly and discriminating monopoly methods, but little has been done in the area of aesthetic values. Techniques for including such values in project evaluation need to be further researched. Tradeoff models developed by market researchers, the advertising industry, social psychologists and sociologists may have some applicability. Methodology for including proposed multiple objective functions in project analysis is also a critical need. 相似文献
329.
Edward R. Kaynor Irving Howards 《Journal of the American Water Resources Association》1971,7(6):1117-1127
Study of water resource decision-making in Massachusetts demonstrates the existence of many institutional constraints such as the established fee system for consulting engineers, the funding of certain agencies, the institutionalization of equity concerns, overrepresentation of interests, and incompatibility of agency goals. These institutional constraints are attributable in part to certain broadly-based value-orientations such as the American pragmatic tradition. However, various lines of evidence indicate that these constraints are less important than other factors in the etiology of decisional outcomes. The outcomes of the decision processes were found to be at variance with the decisions studied, a fact leading to the conclusion that choice of decisions for study should be given more attention. The authors conclude that institutional constraints are important if one is interested in studying how decisions are made, but that what actually happens in the long run cannot be easily ascertained by studying either institutions or the decision-making process. They suggest the need for more research utilizing the incremental theories of Carl Lindblom and the side-effect theories of Albert O. Hirschman. 相似文献
330.
Stan Openshaw 《Journal of Environmental Planning and Management》1986,29(2):66-70
The paper outlines the emerging effects of the Information Technological revolution and examines the likely consequences for planning in Britain. A number of possible scenarios are described as a basis for thinking about the design of a new planning system for the future. 相似文献