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721.
为了对某矿业有限公司低铜废石综合回收利用项目可能产生的职业病危害因素进行辨识、分析和评价,采用检查表、类比法相结合的原则对该项目的铲装、破碎、运输、筑堆等工艺进行分析评价,并利用经验法对浸出、萃取电积工艺进行分析评价。结果表明:类比工程中绝大部分粉尘、噪声检测点的浓(强)度符合国家标准;化学毒物、工频电场接触浓(强)度符合国家标准;电积车间的通风满足要求;萃取车间的事故通风能力不足。评价方法及通风计算方法对同类项目具有借鉴意义。  相似文献   
722.
为研究社会资本对山区居民应急避险能力的影响,在广泛调研的基础上采用结构方程模型分析社会资本与山区居民应急避险能力各要素之间的作用关系。结果表明:个人网络对避险知识和避险意识有显著的正向影响,对避险行为影响不显著;信任与避险知识和避险意识呈显著的正向影响,而与避险行为呈反向影响,但信任可以通过避险知识和避险意识间接正向影响避险行为;互惠对避险知识影响不显著,但互惠与避险意识和避险行为存在显著的正向关系;避险知识和避险意识对避险行为呈显著正向影响,其中避险意识对避险行为影响更为显著。因此可以通过增加山区居民社会资本的方式提高山区居民山洪灾害应急避险能力。  相似文献   
723.
为提高燃气管线突发事件应急处置决策水平和应急响应能力及效率,采用复杂网络理论和灾害链演化机理对燃气管线破裂灾害事件影响进行耦合分析,构建燃气管线破裂灾害链网络和风险评估模型,并计算得出燃气管线破裂灾害链风险度。为更准确地表达无传播路径的灾害事件之间的关系,将灾害网络中所有最短路径长度的最大值作为其最短路径长度,计算表明这种算法更符合灾害传播实际情况。结果表明:通过燃气管线破裂灾害链风险分析,能够为燃气管线灾害风险控制措施和方案制定提供参考,有利于提高燃气管线破裂灾害事件的应急处置能力和决策水平。  相似文献   
724.
为保护铁路线,以某化工厂距离高铁路线最近的丙烯球罐为例,提出丙烯球罐泄漏最小隔离区域划分方法以及2种保护高铁线路方案,利用重气扩散模型和定量风险评价(QRA)软件分别进行丙烯扩散模拟、爆炸模拟,并进行危险与可操作性分析(HAZOP)和保护层分析(LOPA)。结果表明:球罐发生泄漏及火灾爆炸等事故,会给附近铁路线带来严重破坏;丙烯泄漏或球罐因周围其他设备设施或可燃物质着火而温度升高时,保护措施不足;隧道的安全可靠性要高于仅设1道防爆墙,隧道长度需覆盖最小隔离区域的可及范围,在扩散区域内也需设立普通挡墙,在极度危险情况下,需要实施高铁停开等保护措施。  相似文献   
725.
为了研究波浪与抛石潜堤相互作用过程中大自由表面变形和堤内渗流等强非线性紊流运动问题,利用改进的MPS法,建立了模拟波浪与抛石潜堤相互作用的MPS法数值计算模型。模型将抛石潜堤假定为均质多孔介质,采用Drew的二相流运动方程描述多孔介质内外的流体运动;通过在动量方程中增加非线性阻力项,并引入亚粒子尺度紊流模型,模拟波浪与可渗结构物相互作用过程中的紊流运动。选取“U”型管中多孔介质内渗流过程和孤立波与可渗潜堤相互作用两个典型的渗流问题,通过将数值计算结果与理论解和实测值的对比分析,对所提出的MPS法紊流渗流模型的模拟精度进行验证。结果表明:基于改进的MPS法构建的垂向二维紊流渗流模型可以很好地再现 “U”型管中多孔介质内渗流以及波浪作用下可渗潜堤内外的复杂流场,显著缓解流-固界面处的压力震荡与粒子分布不均匀问题,实现了较高的模拟精度。  相似文献   
726.
Safety assessment has a primary role in hazardous operations. Most studies on safety assessment focus on risk and accident modeling, in which safety is absent. These top-down methods are highly dependent on the occurred accidents to establish accidental scenarios, which may make the assessment approach lagging behind the evolving modern systems. Moreover, this “special to general” logic is scientifically suspect in safety assessment. There is a call for the development of safety assessment methods in the presence of system safety to complement risk-focused safety analysis. These methods should provide a framework based on a bottom-up approach to examine system safety from the operational perspective. This paper has attempted to provide a potential solution. In particular, a novel concept of safety entropy is proposed to integrate with The Functional Resonance Analysis Method (FRAM), which is used to form the qualitative understanding of a system. A formula consisted of safety entropy, functional conformability, and system complexity has been established to determine the spontaneity of the safety state-changing process. The proposed method is applied to the safety assessment of a propane feed-control system. The results show the applicability of the method. Nevertheless, the model still needs to be further improved to fulfill better support for safety-related decision problems.  相似文献   
727.
Thermal runaway hazard assessment provides the basis for comparing the hazard levels of different chemical processes. To make an overall evaluation, hazard of materials and reactions should be considered. However, most existing methods didn't take the both into account simultaneously, which may lead the assessment to a deviation from the actual hazard. Therefore, an integrated approach called Inherent Thermal-runaway Hazard Index (ITHI) was developed in this paper. Similar to Dow Fire and Explosion Index(F&EI) function, thermal runaway hazard of chemical process in ITHI was the product of material factor (MF) and risk index (RI) of reaction. MF was an indicator of material thermal hazards, which can be determined by initial reaction temperature and maximum power density. RI, which was the product of probability and severity, indicated the risk of thermal runaway during the reaction stage. Time to maximum rate under adiabatic conditions and criticality classes of scenario were used to indicate the runaway probability of the chemical process. Adiabatic temperature rise and heat of the desired reaction and secondary reaction were used to determine the severity of runaway reaction. Finally, predefined hazard classification criteria was used to classify and interpret the results obtained by this method. Moreover, the method was validated by case studies.  相似文献   
728.
Accidents in chemical industrial parks always cause fateful damage which can be reduced greatly by providing emergency resources sufficiently and timely. One effective way to enhance the emergency response capacity and agility is by pre-positioning of emergency resources for the potential accidents. The Yangtze River Delta of China is a large region where a large number of chemical industrial parks are concentrated. According to the distributing characteristics of demand points in this region, a mathematical model of hierarchical pre-positioning of emergency resources is proposed to ensure that accidents in all chemical industrial parks in this region can be responded timely and effectively. Considering accident domino effect and minimizing the total cost, the model gives optimal decisions of pre-positioning emergency resources, including the location and inventory of depots. The innovative hierarchical pre-positioning method greatly reduces the total cost in the premise of sufficient preparation for supplying emergency resources. Finally, in a visual graph of the Yangtze River Delta, the model is applied and the result shows its applicability.  相似文献   
729.
Academic research and development (R&D) labs are a significant part of academic life. But there can be physical, environmental, and experiment quality risks associated to this activity. Academic labs can present specific experiments, which have associated risks for researchers. Academic labs are also characterized by a high turnover of students and many of them are not fully aware of the level of physical and environmental risks of their activity. Accidents in academic labs with injuries and loss of life are facts that have to be tackled through risk management approaches. The objective of this paper is to present an integrated management approach, tackling risk management and analysis methods. HAZOP (Hazard and Operability Study) and PFMEA (Process Failure Mode and Effects Analysis) enabled, respectively, the analysis of safety and environmental risks. By quantifying the level of risk according to the type of experiment and the research context, it is possible to provide safety to the system. The resulting Digital Poka-Yoke – a mistake-proofing approach – has brought about the desired quality of results in experiments. The proposed approach was validated through a case study monitoring naphthenic corrosion experiments conducted by the Lab of Surface Electrochemistry and Corrosion (LSEC) at the Federal University of Paraná (UFPR). As a consequence, this approach is currently in use at this lab.  相似文献   
730.
Nowadays, pipelines have been extensively used for transporting oil and gas for long distances. Therefore, their risk assessment could help to identify the associated hazards and take necessary actions to eliminate or reduce the risk. In the present research, an artificial neural network (ANN) and a fuzzy inference system (FIS) were used to prepare a new model for pipeline risk assessment with higher accuracy. To reach this objective, the Muhlbauer method, as a common method for oil and gas pipeline risk assessment, was used for determining important and influential factors in the pipeline performance. Mamdani fuzzy model was developed in Matlab software by considering expert knowledge. The outcomes of this model were used to develop an ANN. To verify the developed model, the inter-phase shore pipe of phase 9–10 refinery in the South Pars Gas field was considered as a case study. The results showed that the proposed model gives a higher level of accuracy, precision, and reliability in terms of pipe risk assessment.  相似文献   
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