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161.
文章选取麟游县的北马坊煤矿、郭家河煤矿和北王煤矿为研究区域,对其周边的农田土壤进行野外采样和室内分析,测定Zn、Cr、Pb、Cu、Cd、Hg、As 7种重金属的污染状况。结果表明:测定的7种重金属元素的最大值均超过了陕西省土壤背景值和当地的土壤环境背景值。单因子污染指数评价得出,三矿区周边的土壤Hg元素的污染较严重,局部地区已经达到了重度污染;综合污染指数法评价得出,三矿区均达到了中度到重度污染水平,其中北王煤矿污染水平较高;地质累积指数法评价得出,三矿区Hg元素的累积程度属于中度污染到强污染等级,Cd元素次之。因此3矿区周边的耕地土壤已不同程度的受到重金属的污染,相关部门应该采取一定的措施治理该区的土壤。  相似文献   
162.
总结鹤煤集团近年来在提升以安全理念为核心的安全文化方面值得推广的经验与做法。分析了公司推行的追求"文明"的安全目标理念、"责任重于泰山"的安全责任理念、尊重客观规律的安全风险理念、事故背后有故事的安全防范理念、赛马机制下的"两条腿走路"理念、"木桶理论"下的螺旋上升理念、系统工程论的齐抓共管理念以及以"管理为中心"的持续改进理念的理论和内涵,总结了以这八条理念为核心的安全文化建设与保障措施。最后进行实施效果的定量评估,共抽样分析179名员工,发现全部安全理念内容都有不同程度的提高。成果有助于类似煤矿企业树立安全理念、更好的建立安全文化,提高员工安全素质。  相似文献   
163.
Investigation of explosion characteristics of coal dust was undertaken as a part of regular research program at CSIR-CBRI, Roorkee, India, for designing explosion safety measures for coal dust handling installations. This paper presents results of detailed experimental work on determination of Limiting Oxygen Concentration (LOC) and influence of reduced oxygen levels on explosion severity data for two types of coals with varying volatile matter as 27.18% (coal A) and 19.69% (coal B) from Jharia coalfield of India determined at ambient conditions with 20-L Spherical Vessel established at CSIR-CBRI. The effects of coal particle size and moisture content were evaluated. Data presented will be used for hazard analysis, designing explosion preventive measures, and explosion severity reduction by involving the use of inert gases for installations handling pulverized coal with similar nature. The importance of ignition source energy in determining LOC data is highlighted. The data collected lead to an extension of the current data for coal dusts as found in the literature. Limiting oxygen concentrations were found as 7% for coal A and 8% for coal B for the size representative to that used in pulverized coal boilers and moisture content ~4%.  相似文献   
164.
In this paper, a real options based binominal lattices model for the investment of coal bed methane (CBM) is conducted. CBM prices and market demand are incorporated into the model as the predominant uncertain factors and it is solved by using the bidimensional binominal lattices approach. Then the model is employed to evaluate the investment in CBM projects in China, and the effect of related policies is analyzed. The empirical results demonstrate that the model can be used to offer a better explanation of why the CBM industry has developed slowly in China from an investment perspective. It is found that the current policy environment is not positive enough to attract investment in the CBM industry. Among various factors, CBM prices yield the most significant effect on stimulating investment in CBM development. Increasing the price subsidy is also an effective policy to stimulate investment and promote the development of the CBM industry in China.  相似文献   
165.
In this paper we quantify the additional water quality benefits that can be achieved through coordinated cumulative impact management. To do this we simulate coordinated and un-coordinated revegetation investments and compare their impact on achieving regional water quality goals. Our results show that coordination between multiple mining companies achieves additional benefits since prioritization is enabled across a broader range of investment opportunities. Additionally, when coordinated investment is permitted beyond the boundaries of coal mining leases, results show that additional benefits are greatly enhanced since these regions provide more rewarding investment opportunities. Results illustrate (a) how regional coordination may influence reputational benefits of investments, and (b) that coordination is beneficial when investment opportunities are unevenly distributed across the landscape. When additional benefits are achievable, we suggest that mining companies should develop collective investment projects with an understanding of how coordination influences project costs. Similarly, investment projects should be developed with an understanding of investment tradeoffs and how these may adversely impact on regional stakeholders and hence industry reputation. The mining industry has significant potential to contribute to regional wellbeing; however, land management policies must be flexible and promote incentives to enable companies to invest beyond compliance.  相似文献   
166.
阐述了煤炭在我国能源中的地位及其与环境之间的矛盾,介绍了我国现行的煤炭资源环境保护政策,之后就化解煤炭资源环境保护政策与其在现实中的矛盾提出了几项措施。  相似文献   
167.
A non-homogeneous variable-elasticity-of-substitution production function is estimated using data for the Welsh coal industry. From 1961 to 1976 output declined, returns to scale increased and the elasticity of substitution fell. At the end of the period, the elasticity of substitution between capital and labour in the coal industry is still large and there may be room for greater employment in the industry at a time of high and rising unemployment, subject to other overall considerations. While marginal productivity of labour in physical terms has been stagnant, price rises in the industry in recent years have been in excess of what was needed to finance wage settlements. Perhaps price rises granted to the coal industry by the UK government were justified, but they require closer scrutiny.  相似文献   
168.
用矿井水作蚕豆微核实验,讨论了F^-、Hg^2+和Cr^6+单一及复合污染对蚕豆微核的影响。结果表明,F^-、Hg^2+和Cr^6+单一污染均对微核产生显著影响,随着氟化物浓度和Cr6+浓度的增加,微核率呈上升趋势;随着Hg^2+和Cr^6+浓度增加,微核率呈先上升后下降的趋势。两因子方差分析显示,F^-和Hg^2+复合污染对蚕豆微核率有显著影响。  相似文献   
169.
杨利  赵玲  孟庆虎 《环境科技》2008,21(1):65-67
随着淮南矿业集团谢桥煤矿的发展,矿区生产和生活用水量日趋紧张,解决缺水问题的有效途径是合理开发利用矿井水资源。在此论述了煤矿矿井水资源化的必要性,给出了矿井水处理工艺流程、主要建(构)筑物、主要设备等,说明了开发利用矿井水资源具有良好的社会、环境和经济效益。  相似文献   
170.
燃煤砷污染及控制技术研究现状   总被引:1,自引:0,他引:1  
本文对国内外煤燃烧过程中砷的污染及其控制的研究现状进行了综述。概括了煤燃烧过程中砷的排放对环境产生的危害,分析煤中砷的赋存状态、燃烧过程的转化形态、固砷剂对煤中砷的作用和砷在飞灰中的富集状况,讨论燃前洗煤、燃煤固砷、烟气除尘技术减少煤中砷污染排放的研究现状及可行性;根据洁净煤技术应用现状讨论了动力配煤技术在高砷煤砷污染防治中的积极意义。指出加强对煤中砷的释放、控制理论及实用技术的研究,减少砷污染物排放对环境的污染是今后研究的方向。  相似文献   
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