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91.
Traditional biological removal processes are limited by the low solubility of halogenated compounds in aqueous media. A new technology appears very suitable for the remediation of these volatile organic compounds (VOCs). Solid/gas bio-catalysis applied in VOC remediation can transform halogenated compounds directly in the gas phase using dehydrated cells as a bio-catalyst.  相似文献   
92.
城市垃圾甲烷气体排放及减排对策   总被引:6,自引:0,他引:6  
本文讲述了城市垃圾的现状以及影响垃圾甲烷排放的各种因素,并根据IPCCGuidelines(1995)提供的方法对1990~2010年江浙沪地区城市垃圾甲烷排放量的变化趋势进行了预测统计计算,1990年江浙沪地区城市垃圾甲烷排放量为7123万吨,2010年预测的甲烷排放量为26676万吨,本文就垃圾中甲烷的排放提出了切实可行的减排方案。  相似文献   
93.
对钻井废物污染的全过程控制   总被引:4,自引:1,他引:4  
在钻井作业过程中控制废物的排放量和毒性,变末端处理为全过程控制,采取各种措施预防钻井废物的污染是近年来国外油气田环保工作的一项重要内容。本文就采用小井眼钻井工艺;减少井眼冲蚀;强化环境管理;提高钻井液固控系统的处理效率;开发各种合成基钻井液;采用低毒无害的钻井液化学添加剂等6个方面讨论了减少钻井废物产生量的途径和降低钻井液及添加剂对环境的影响  相似文献   
94.
    
ABSTRACT

Climate change is expected to contribute to global inequality, and exacerbate ecological risk for the world's poor. Despite recent trends within waste management academic discourse, which has begun to engage with inequality, and its underlying socio-economic and socio-political causes, discussions of inequality have so far remained absent from our investigations on climate change's impacts on waste management systems and practices. The purpose of the discussion is to call for a centring of inequality within our waste and climate discourse. I identify two main pathways for scholarly investigation, specifically, developing alternative waste management solutions for contexts in which waste management systems fail, which do not just perpetuate existing inequalities, and addressing the growing inequality in waste management technology and practice between the Global North and the Global South.  相似文献   
95.
    
High-pressure, near-critical liquids were used as float-sink separation media for the microsortation of polyolefin mixtures and PET/PVC mixtures. Near-critical carbon dioxide was used for the refinement of the polyolefins, and sulfur hexafluoride was used to separate post-consumer PVC from PET. Preliminary experiments indicated that there was no overlap in the density ranges of post-consumer HDPE, LDPE and PP containers. There was no overlap in the PET and PVC densities, with the exception of a single PVC packaging material with a density in the PET range. These initial results indicated that a float-sink separation was a viable means of microsortation. Separations of 91% LDPE (1/8′ beads)/9% PP (1/8′ chopped strands) resin mixtures and mixed post-consumer polyolefin flakes were then conducted in a laboratory-scale, 1-I batch apparatus. This apparatus not only permitted the observation of the separation, but also enabled the separated fractions to be removed from the high-pressure environment. The results indicated that LDPE purity of greater than 98.9% was obtained in 3 min or less if (a) the fluid density was 0.018 g/cm3 greater than the PP density and only 0.002 g/cm3 less than the LDPE density, thereby providing the greatest buoyancy force for the removal of the PP, (b) the fluid was recirculated upward through the bed of mixed plastics, facilitating the upward movement of the PP, and (c) the loading was kept at levels below 40% by volume. HDPE purity of 99% was also attained with clean, dry, post-consumer mixed plastic flakes. The loadings for these separations were very low, however, due to the difficulty in agitating the mixed bed of plastics using fluid recirculation. An economic analysis of these microsortation processes indicated that the value of the sorted plastics relative to the mixed feed must increase by approx. $0.08/lb for the CO2-based separation and approx. $0.27/lb for the SF6-based separation to justify the implementation of these high-pressure processes.  相似文献   
96.
关于电子废物资源循环利用的思考   总被引:3,自引:0,他引:3  
论述了我国电子废物的产生及污染现状,分析了日本、欧美等发达国家促进电子废物循环利用的对策,提出了我国电子废物循环利用的建议。  相似文献   
97.
研究从COD测定的废液中回收银的工艺.在废液中分离出氯化银,经洗涤后加锌置换,还原为银.该工艺简便易行,原材料普通易得.适用于实验室及工业生产的应用.回收银的纯度可达99%以上.  相似文献   
98.
    
Present methods of disposal of today's hazardous household chemicals in the United States are frequently not acceptable because of pathways to groundwater, surface water, and the atmosphere. This report identifies potentially hazardous liquid waste in the household, notes current disposal practices, and recommends an improved management plan that utilizes consumer education, manufacturer cooperation, and governmental intervention. Laws requiring uniform disposal labeling on packaging are critical. Local, county, and state governments must be encouraged to coordinate the necessary infrastructure. Managing hazardous household wastes now will mitigate potential disposal problems.  相似文献   
99.
  总被引:2,自引:0,他引:2  
Uncertainty plays an important role in water quality management problems. The major sources of uncertainty in a water quality management problem are the random nature of hydrologic variables and imprecision (fuzziness) associated with goals of the dischargers and pollution control agencies (PCA). Many Waste Load Allocation (WLA) problems are solved by considering these two sources of uncertainty. Apart from randomness and fuzziness, missing data in the time series of a hydrologic variable may result in additional uncertainty due to partial ignorance. These uncertainties render the input parameters as imprecise parameters in water quality decision making. In this paper an Imprecise Fuzzy Waste Load Allocation Model (IFWLAM) is developed for water quality management of a river system subject to uncertainty arising from partial ignorance. In a WLA problem, both randomness and imprecision can be addressed simultaneously by fuzzy risk of low water quality. A methodology is developed for the computation of imprecise fuzzy risk of low water quality, when the parameters are characterized by uncertainty due to partial ignorance. A Monte-Carlo simulation is performed to evaluate the imprecise fuzzy risk of low water quality by considering the input variables as imprecise. Fuzzy multiobjective optimization is used to formulate the multiobjective model. The model developed is based on a fuzzy multiobjective optimization problem with max–min as the operator. This usually does not result in a unique solution but gives multiple solutions. Two optimization models are developed to capture all the decision alternatives or multiple solutions. The objective of the two optimization models is to obtain a range of fractional removal levels for the dischargers, such that the resultant fuzzy risk will be within acceptable limits. Specification of a range for fractional removal levels enhances flexibility in decision making. The methodology is demonstrated with a case study of the Tunga–Bhadra river system in India.  相似文献   
100.
In Korea due to rapid economical growth followed by urbanisation, breakage of large traditional families into small nuclear families, continuous changes in equipment features and capabilities causes tremendous increase in sale of new electrical and electronic equipment (EEE) and decrease in sale of used EEE. Subsequently, the ever-increasing quantity of waste electrical and electronic equipment (WEEE) has become a serious social problem and threat to the environment. Therefore, the gradual increase in the generation of WEEE intensifies the interest for recycling to conserve the resources and protect the environment. In view of the above, a review has been made related to the present status of the recycling of waste electrical and electronic equipment in Korea. This paper describes the present status of generation and recycling of waste electrical and electronic equipment, namely TVs, refrigerators, washing machines, air conditioners, personal computers and mobile phones in Korea. The commercial processes and the status of developing new technologies for the recycling of metallic values from waste printed circuit boards (PCBs) is also described briefly. Since 1998, three recycling centers are in full operation to recycle WEEE such as refrigerators, washing machines and air conditioners, having the total capacity of 880,000 units/year. All waste TVs are recently recycled on commission basis by several private recycling plants. The recycling of waste personal computers and mobile phones is insignificant in comparison with the amount of estimated obsolete those. Korea has adopted and enforced the extended producer responsibility (EPR) system. Korea is making consistent efforts to improve the recycling rate to the standards indicated in the EU directives for WEEE. Especially environmentally friendly and energy-saving technologies are being developed to recycle metal values from PCBs of WEEE.  相似文献   
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