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51.
基于HAZOP的方法对炼化企业电力系统进行分析,可以有效提高炼化企业电气安全平稳运行水平,降低发生大面积停电事故的风险。该分析方法不同于化工企业的HAZOP分析方法,在分析流程细节中,结合电气专业化的特点,形成了一套具有炼化企业供电系统风险评估特色的评价方法,为炼化企业供电系统在规划、设计、运行等阶段提供依据。  相似文献   
52.
Based on the microorganism kinetic model, the formula for computing hydraulic retention time in a membrane bioreactor system (MBR) is derived. With considering HRT as an evaluation index a combinational approach was used to discuss factors which have an effect on MBR. As a result, the influencing factors were listed in order from strength to weakness as: maximum specific removal rate K, saturation constant Ks, maintenance coefficient m, maximum specific growth rate ,ua and observed yield coefficient Yobs. Moreover, the formula was simplified, whose parameters were experimentally determined in petrochemical wastewater treatment. The simplified formula is θ= 1.1( 1/β -1)(Ks S)/KXo , for oetroehemical wastewater treatment K and Ko eaualed 0.185 and 154.2, resoectively.  相似文献   
53.
车站、机场、码头火灾风险管理定量方法的研究   总被引:2,自引:0,他引:2  
在对车站、机场、港口等旅客站点火灾风险因数识别的基础上,提出火灾风险定量管理模型,经验和研究证明,该模型十分有效,是火灾风险定量管理的一个有效可行的工具,对火灾风险管理的方法进行了阐述/。  相似文献   
54.
针对安全性评价过程评价周期长,工作量大,手段落后等问题,依据安全检查表法及评价理论,以Microsoft Visual Basic6.0为开发工具,开发了火力发电厂安全性评价计算机辅助系统,在企业局域网中实现,可以减少安全评价过程中大量重复工作,提高效率,其它行业也可以基于此方法,开发相应的计算机辅助评价系统。  相似文献   
55.
本文论述了利用风险投资加快我国环保产业发展的重要性,并提出相关建议。  相似文献   
56.
商厦火灾是火灾中危害性较大的灾害之一,常常造成人员的大量伤亡和巨大的财产损失。商厦火灾危险性评价是一个减少火灾危险性的可行方法。在基于影响商厦火灾危险性因素之上,讨论了评价指标体系的建立及量化和权重的处理方法,然后应用模糊数学理论建立了评价商厦火灾的模糊评价模型,对商厦火灾的预防与商厦消防管理具有指导意义。  相似文献   
57.
Open-cast lignite mining in the Lusatian mining district resulted in rehabilitated mine soils containing up to four organic matter types: (1) recent plant litter, (2) lignite deposited by mining activity, (3) carbonaceous ash particles deposited during amelioration of the lignite-containing parent substrate and (4) airborne carbonaceous particles deposited during contamination. The influence of lignite-derived carbon types on the organic matter development and their role in the soil carbon cycle was unknown. This paper presents the findings obtained during a six year project concerning the impact of lignite on soil organic matter composition and the biogeochemical functioning of the ecosystem. The organic matter development after rehabilitation was followed in a chronosequence of rehabilitated mine soils afforested in 1966, 1981 and 1987. A differentiation of the organic matter types and an evaluation of their role within the ecosystem was achieved by the use of 14C activity measurements, 13C CPMAS NMR spectroscopy and wet chemical analysis of plant litter compounds. The results showed that the amount and degree of decomposition of the recent organic matter derived from plant material of the 30 year old mine soil was similar to natural uncontaminated forest soil which suggests complete rehabilitation of the ecosystem. The decomposition and humification processes were not influenced by the presence of lignite. On the other hand it was shown that lignite, which was thought to be recalcitrant because of its chemical structure, was part of the carbon cycle in these soils. This demonstrates the need to elucidate further the stabilisation mechanisms of organic matter in soils.  相似文献   
58.
我国矿业"走出去"风险勘探问题分析与建议   总被引:1,自引:0,他引:1  
根据我国资源条件和经济发展的需要以及获取国外资源的方式进行比较分析得知,我国非常有必要到国外进行风险勘探。虽然我国经历了多年境外风险勘探的实践和探索,但是步伐缓慢,在实践中面临很多问题。对此,作者提出了我国境外风险勘探问题的建议。  相似文献   
59.
/ The risk tropospheric ozone poses to forests in the United States is dependent on the variation in ozone exposure across the distribution of the forests in question and the various environmental and climate factors predominant in the region. All these factors have a spatial nature, and consequently an approach to characterization of ozone risk is presented that places ozone exposure-response functions for species as seedlings and model-simulated tree and stand responses in a spatial context using a geographical information systems (GIS). The GIS is used to aggregate factors considered important in a risk characterization, including: (1) estimated ozone exposures over forested regions, (2) measures of ozone effects on species' and stand growth, and (3) spatially distributed environmental, genetic, and exposure influences on species' response to ozone. The GIS-based risk characterization provides an estimation of the extent and magnitude of the potential ozone impact on forests. A preliminary risk characterization demonstrating this approach considered only the eastern United States and only the limited empirical data quantifying the effect of ozone exposures on forest tree species as seedlings. The area-weighted response of the annual seedling biomass loss formed the basis for a sensitivity ranking: sensitive-aspen and black cherry (14%-33% biomass loss over 50% of their distribution); moderately sensitive-tulip popular, loblolly pine, eastern white pine, and sugar maple (5%-13% biomass loss); insensitive-Virginia pine and red maple (0%-1% loss). In the future, the GIS-based risk characterization will include process-based model simulations of the three- to 5-year growth response of individual species as large trees with relevant environmental interactions and model simulated response of mixed stands. The interactive nature of GIS provides a tool to explore consequences of the range of climate conditions across a species' distribution, forest management practices, changing ozone precursors, regulatory control strategies, and other factors influencing the spatial distribution of ozone over time as more information becomes available.KEY WORDS: Ecological risk assessment; GIS; Ozone; Risk characterization; Forests; Trees  相似文献   
60.
用事故树分析法进行炼厂油罐爆炸事故的环境风险评价   总被引:5,自引:0,他引:5  
龙军  俞珂 《化工环保》1996,16(2):113-119
论述了风险、风险评价、环境风险评价的概念及其主要内容,说明利用事故树分析法进行工程环境风险评价的程序和方法。并运用这种方法对某炼厂油罐爆炸事故进行了大气环境风险评价。  相似文献   
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