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901.
为掌握东营市化工聚集区地下水受有机污染的总体程度,对该市三县两区96个调查点位的地下水TOC进行了监测。结果表明:化工聚集区地下水TOC质量浓度分布范围为1.5~19.6 mg/L,87.5%的数据集中在2~10 mg/L区段,其中2~4 mg/L的区段数据最密集,数据分布呈对数正态分布。受区域内外部因素共同影响,地下水超标率和异常值比率分别达到62.5%和18.8%,且由南向北呈明显上升趋势;存在浓度均值超标和异常突变数据的化工聚集区数量分别占调查总量的75%和62.5%。地下水TOC受环境地质分布影响显著,黄泛平原区比山前平原区污染范围和程度更高;河口区和广饶井罐区分别是东营市和广饶县地下水污染最严重的地区,广饶县西北部是东营市地下水TOC水质最好的地区。  相似文献   
902.
从风险物质数量、风险诱发因素及风险防控能力角度出发,采用加权评分法,结合周边环境敏感受体情况,对沈阳市某化工园现状做环境风险评估。结果表明:JHYSD和XJHX的区域环境风险值贡献最大,分别为3.08和2.59,约占园区内总风险值的41.2%;该化工园综合环境风险值为13.57,构成该综合风险值的各分项大小不同,其中,RIS_(危险废物)分项环境风险最大,贡献率达到28.89%,其次为RIS_(大气),贡献率达27.34%,其余三者顺序为RIS_(化学品)RIS_水RIS_(累积)。  相似文献   
903.
The purpose of this study is to examine the critical success factors of sustainable manufacturing practices (SMPs) in Malaysian automotive industry. The questionnaires were designed and distributed to the 50 respondents. The pilot study sample consists of 26 respondents from 50 questionnaires, with an average response rate of 52%. The results of reliability analysis show that social responsibility is critical factor influencing the direct SMPs implementation success. By implementing SMPs in Malaysian automotive industry, it can assist company to improve the quality of management. Thus, this study recommends that the future research explore the influence of SMPs on sustainable performance in Malaysian automotive industry.  相似文献   
904.
Sugar industries require a large amount of water for processing, and also generate large amounts of high-degree polluted wastewater. To maintain the water balance in the industry, it is imperative that effective treatment methods need to be devised to treat the wastewaters. The main aim of the present work is to treat the sugar industry wastewater by combined thermal and electro-oxidation methods with a metal and a catalyst based on ferrous material. Results showed a reduction of 75.6% of COD and 79.2% of colour content with thermal treatment, and 97.8% of COD and 99.7% of colour with combined thermal and electrocoagulation treatments under optimum conditions. These reduction levels are adequate for recycling limits.  相似文献   
905.
Abstract

Energy management in small to medium enterprises (SMEs) remains undeveloped due to competing priorities and a lack of specialist knowledge. However considerable savings can be demonstrated where companies take the time to investigate their energy use. Savings of over 20% can be achieved through changes to operational and behavioural practice. Additional benefits, such as improved production tracking and improved maintenance, can been seen which add to the value in undertaking an energy monitoring and targeting (M&T) plan. The method described involves the application of a series of ‘virtuous’ cycles of engagement and energy savings that can be applied from the highest factory level right down to a specific machine. The analysis of overall energy use from utility bills and the visualisation of typical machine power profiles aid in understanding the drivers of energy consumption and in engaging management in energy efficiency. The monitoring of specific machines in production highlights the significant consumption of electricity during non-productive times. The development of energy performance indicators is described for product variations which can be useful in tendering for business and selecting optimum production pathways. The approach is illustrated with data from a case study of a precision engineering SME based in Limerick, Ireland.  相似文献   
906.
Chromium speciation in the blood of metal-on-metal hip implant patients   总被引:1,自引:0,他引:1  
The objective of this study was to determine the valence state of chromium (Cr) in the blood of individuals with Cr-containing metal hip implants. Serum and red blood cell (RBC) Cr concentrations from 52 patients with Cr-containing total hip arthroplasties were measured preoperatively and at 3, 12, and 24 months postoperatively. Geometric mean and median pre-surgery serum Cr concentrations were consistently below 0.2 µg/L, while geometric mean and median pre-op RBC Cr concentrations were typically about four- to six-fold higher than the serum values. A significant 5- to 13-fold increase was found in the mean and median serum Cr concentrations three months post-surgery, with an 8- to 18-fold rise at 12 and 24 months, respectively. Steady-state serum concentrations were reached between 3 and 12 months. In contrast, there were no marked differences in mean and median RBC Cr concentrations pre- and post-surgery. Slope regression analysis for our data was similar to those reported for Cr(III) in spiked blood samples. The analysis showed that Cr released from hip implants preferentially distributed into serum and not RBC, indicating that the form of Cr present in blood of hip implant patients was in the form of non-toxic Cr(III). Our findings indicate that blood Cr concentrations Cr(III) associated with metal implants do not pose an adverse health risk to patients, which is in agreement with findings published by most investigators.  相似文献   
907.
Natural resource industries are increasingly significant actors in environmental decision-making. Possessing vast institutional and technical capacity, firms have an important role to play in ‘new’ governance strategies such as collaboration. These strategies are often based upon assumptions of equitable influence. This paper investigates the nature of resource industry participation in collaborative water governance in Canada, and the potential consequences of that participation as investigated using power theory. The study used comparative cases to reveal that resource industries are able to shape collaboration, and the issues collaborated upon, at multiple analytical levels both internal and external to the collaborative process in ways not available to other actors. Analysis also revealed that resource industry participation in collaboration did not reflect a commitment to engage in shared learning and the reexamination of values and interests as presupposed by collaborative theory. Collaboration is thus challenged in producing equitable, representative outcomes when resource industries participate.  相似文献   
908.
储罐是石化行业挥发性有机物(VOCs)无组织排放源的重要组成部分。采用美国环保署推荐的储罐VOCs排放量计算公式,以云南某炼化企业的典型热渣油立式固定顶罐以及北京某石化企业的汽油外浮顶罐和甲苯内浮顶罐为基准案例进行储罐大呼吸损耗量的计算,考察了其影响因素,总结出影响储罐大呼吸损耗的关键参数,并有针对性地提出降耗措施。结果表明:影响固定顶罐大呼吸损耗的关键参数为气相分子摩尔质量、日平均液体表面温度和年周转量;影响外浮顶罐大呼吸损耗的首要关键参数为罐壁黏附系数,其次为年周转量和有机液体的密度;影响内浮顶罐大呼吸损耗的首要关键参数为罐壁黏附系数,其次为年周转量和固定顶支撑柱数量。  相似文献   
909.
姚琪  刁杰 《化工环保》2017,37(3):289-293
结合我国氟化工行业发展现状,分析了含氟"三废"产生情况及处置方法的最新研究进展,并通过实际工程案例进行论述。氟化工生产过程污染物主要有含氟废气及副产氯化氢、含氟高沸物及含氟污泥等。通过将氯化氢用于工业清洗及制备氯化钙、氯化铝等化学品能够合理消耗副产盐酸。焚烧处理含氟有机废气产生的氟化氢气体经水洗后副产氢氟酸。含氟高沸物通过精馏分离出高沸物组分生产高附加值产品。含氟污泥可制成建筑材料,最优工业化利用途径仍在积极研究中。  相似文献   
910.
海洋盐沼环境中金属的行为研究   总被引:4,自引:0,他引:4  
详细论述了海洋盐沼环境中金属的行为及其化学/物理影响因素,其中包括盐沼区域的划分、影响金属的因素、金属的行为、盐沼植物与金属的关系。指出,重金属对盐沼植物生物初期有一定程度的危害,利用某些盐沼植物可监测重金属的污染状况。  相似文献   
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