Papers by Keyword: Brown Field

Abstract: Brownfield, as a result of old and polluting industries being relocated away from urban areas, is an emerging problem since these contaminated lands pose and obstacle to urban and economic development. Semi Volatile Organic Compounds (SVOCs) are common contaminants found in brownfield sites that used to be manufacturing industries or agrochemical plants. Chemical oxidation has the potential to provide rapid, cost-effective treatment for brownfield contaminated with SVOCs. In this study, a pilot study of chemical oxidation was demonstrated for brownfield remediation in a specific site that used to be an agrochemical plant in Jiaxing, Zhejiang Province. Preliminary site characterization suggested that the site was primarily contaminated by o-anisidine and its derivatives with trace amount of o-nitrochlorobenzene and other chemicals. The contaminants soil was pretreated and mixed with two selected oxidants at different soil-to-oxidant ratio. Soil samples were collected and analyzed before and after the treatments to compare the concentration changes of primary contaminants. The results showed that combinations of TA-1 oxidant and AOP-2 oxidant with several different ratios could provide 90% or more removal of targeted contaminants in two weeks, with an average cost of oxidants per ton of soil around 400 RMB. This is the first report for brownfield remediation case study in Zhejiang since “Clean Soil Action” was initiated by Zhejiang Provincial Government. The successful treatment for SVOCs contaminated brownfield in this study would promote chemical oxidation treatment to be employed in brownfield sites with similar situations in Zhejiang province in the future.

Abstract: With the accumulation of solid waste in developing countries, sites of closed landfills have attracted attentions, which can be sorted as one typical brown field in urban area. Taking closed municipal solid waste landfills as examples, case study for turning brown land into green space in Europe and USA was carried out, based on which, suggestions on the ecological regeneration of brown land in China were put forward. It was put forward that for closed landfill constructed in the earlier days, the reliable procedure for the site generation should be reclamation. If it is not possible to carry out the reclamation engineer at present, establishment of trees on the top soil of closed landfill, in other words, eco-regeneration can reduce the negative effects of landfill as far as possible. For the developing countries, reduction, stabilization and recycling of solid waste should be the final solution for solid waste.

Abstract: With the rapid development of urbanization and industrialization in Chongqing, effect of heavy metals on brownfield has been paid more and more attention. 8 brownfields in steel industry, 15 brownfields in chemical industry, 18 brownfields in machining industry and 7 brownfields in pharmaceutical industry were selected as research objects, and eight heavy metals including mercury (Hg), lead (Pb), arsenic (Ar), cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni) and zinc (Zn) in soil were analyzed. Single factor pollution index (SFPI) and integral pollution index (IPI) was used to assess the pollution degree of these sites. The comprehensive results showed that the brownfields in the 4 studied industries had been affected by the heavy metals which produced in industrial activities. Machining industry had the greatest impact on the brownfield in Chongqing, also, the effect of chemical industry and steel industry to the soil were tremendous. Only pharmaceutical industry had little influence on the soil environment.

Abstract: To develope a practicable stabilization method for remediation chromium contaminated soil, reductant and chelate reagent were investigated for stabilization artificical chromium contaminated soil, and the stabilization effect was tested through extraction toxicity assay after stablized soil was oxidized at pH 12. The experimental results showed that the composition of sodium bisulfite & ammonium pyrrolidine dithiocarbamate was an ideal stabilizer of chromium in soil, and the extraction toxicity was much less than that of classical stabilized chromium polluted soil with only reductant or the maximum critical value in GB16889-2008, which suggested that the composition of reductant & compound of dithiocarbamate might be practically appllied for remediation chromium contaminated soil because it was likely to remain chromium much more stable in soil for a long time and significantly decrease Cr mobility.

Abstract: Environmental management on brownfields is still a new field in China, and it is imperative to study and develop the related environmental management system to adapt to the present situations of our country due to rapid urbanization and redevelopment of brownfields in recent years. In order to ensure environmental conditions for "livable Chongqing" and "healthy Chongqing", suggestions for revising the present "Environmental management measures of contaminated sites in Chongqing" were proposed in this paper based on fully analyzing the status of urban soil pollution control and management in our country, understanding successful experiences of brownfield management in developed countries, and summarizing the shortcomings of environmental management on evacuated industrial sites in Chongqing.

Abstract: The purpose of this paper is to establish a complete appraisal system and study on comprehensive environment risk assessment of brownfield reuse in procedure and method through the case of Xishan District, according to life cycle theory. Methods employed include system analysis, analytic hierarchy process and grey evaluation method. The result shows that,(1) The life cycle of brownfield reuse can be divided into three stages which are the confirmation and preparation stage, the control and treatment stage, the maintenance and supervision stage, including policy and legal risk, economic risk, organizational risk, pollution risk, etc, eight elements.(2)the environmental risk of Xishan District is in medium level. Additionally, due to the polluting and complexity of brownfield, it should be respond to the necessary control. It is concluded that the comprehensive environment risk assessment of brownfield reuse has high scientific and practical by using analytic hierarchy process and grey evaluation method.