码头油品泄漏扩散事故危险危害评价

运用“泄漏扩散”模型对某码头油品泄漏扩散事故危险危害程度进行了评价,得到了爆炸危险区域和中毒危害区域的面积,为码头制定应急救援预案提供了依据.     

基于环境风险的危险废物填埋场安全寿命周期评价

通过系统分析危险填埋场的设计功能,结合安全寿命周期的定义,对危险废物填埋场的安全寿命周期进行了定义.在此基础上,通过文献查阅和理论推导确定了描述危险废物填埋场主要单元性能衰减的老化模型,并结合课题组开发的渗漏环境风险分析模型,建立了危险废物填埋场的安全寿命评估模型,并选择中部某危险废物填埋场进行了案例研究.结果表明:随着防渗材料老化以及导排层淤堵,渗滤液渗漏量将逐渐增加,其安全贮存功能将逐渐丧失,并逐渐达到其安全寿命周期.仅就本案例而言,该填埋场的安全寿命周期为385a;对安全寿命周期相关参数的敏感性分析表明,浸出浓度与填埋场安全寿命周期呈负相关,包气带厚度和含水层厚度与安全寿命周期呈正相关,相关系数分别为-0.79、0.99和0.72,这说明包气带厚度对安全寿命周期影响更大,其次为浸出浓度,最后为含水层厚度;应加强填埋场相关单元老化模型研究,开展其他因素对填埋场安全寿命周期的影响,进一步完善危险废物填埋场安全寿命周期评价理论和方法.     

Alternative transportation fuel standards: Welfare effects and climate benefits

This paper develops an integrated model of the fuel and agricultural sectors to analyze the welfare and greenhouse gas emission (GHG) effects of the existing Renewable Fuel Standard (RFS), a Low Carbon Fuel Standard (LCFS) and a carbon price policy. The conceptual framework shows that these policies differ in the incentives they create for the consumption and mix of different types of biofuels and in their effects on food and fuel prices and GHG emissions. We also simulate the welfare and GHG effects of these three policies which are normalized to achieve the same level of US GHG emissions. By promoting greater production of food-crop based biofuels, the RFS is found to lead to a larger reduction in fossil fuel use but also a larger increase in food prices and a smaller reduction in global GHG emissions compared to the LCFS and carbon tax. All three policies increase US social welfare compared to a no-biofuel baseline scenario due to improved terms-of-trade, even when environmental benefits are excluded; global social welfare increases with a carbon tax but decreases with the RFS and LCFS due to the efficiency costs imposed by these policies, even after including the benefits of mitigating GHG emissions.     

HFC-2制冷剂泄漏危险性分析

新型制冷剂HFC-32具有较低的全球变暖潜值（ GWP）、零臭氧消耗潜值（ ODP）使其成为较为理想的制冷剂替代物。但是由于HFC-32本身具有弱的可燃性,其一旦泄漏则有可能引起火灾等事故。使用CFD数值模拟软件分析不同的通风条件及HFC-32泄漏速率条件下,室内的气流组织形式。研究发现顶板送风条件下,随着HFC-32泄漏速率的增加室内危险性区域的范围越大;当HFC-32的泄漏速率一定的条件下,送风风速为4m/s时室内的危险性区域的范围最小。     

中压天然气管道泄漏扩散模拟研究

建立了埋地中压天然气管道发生泄漏时时的数学模型,将土壤视为各向同性的多孔介质,采用FLUENT对天然气在土壤中的扩散规律及浓度分布进行模拟,分析不同时刻地表的危险区域范围,并对比了不同管道压力、泄漏孔径大小、泄漏位置等工况下危险半径随时间的变化。结果表明:管道压力越大,泄漏的体积流量越大,同一时间危险范围越大;相同的泄漏压力下,泄漏孔径对危险半径没有很大影响;不同泄漏孔位置,泄漏初期向上开口时危险半径最大,一段时间后向下开口危险半径最大。     

基于GIS的有毒气体储罐泄漏扩散及其过程模拟

为动态模拟有毒气体储罐泄漏扩散事故（toxic gas vessel leakage and dispersion,以下简称为TLD）的扩散过程,基于高斯点源瞬时泄漏模型,添加时间因子,将TLD的泄漏过程转换为一系列瞬时点源泄漏的叠加过程,从而获得任意时刻、任意位置的有毒气体浓度分布方程。以某氯气泄漏事故为例,模拟了有毒气体的扩散过程。结果表明,在初始阶段有毒气体储罐泄漏扩散的影响范围是逐步增大的;泄漏持续到一定时间,扩散过程趋于稳定;若假设泄漏条件不变,则此后的扩散过程类似于连续泄漏,影响范围保持不变。经与ALOHA软件的计算结果对比,两者在泄漏5分钟以后的模拟结果基本一致,本文所述模型模拟计算结果可信。     

浅议起重机械接地电阻的检测

近年来,随着起重机械在电气系统上的长足发展,起重机械电气系统的复杂化给予检验检测人员带来较多困惑,同时起重机械由于漏电而造成的安全事故也时有发生,此类事故又多与接地系统缺失或不完备有关。在起重机械电气系统中,最为基础,同时也是最为重要的部分是起重机械的接地系统,接地系统的安全设置,可以避免因为漏电所连成的操作人员触电事故。本文对起重机械接地系统进行完整分析,并对检验人员现场检验起重机械接地系统给出相关建议。     

基于粒子群算法的燃气管线泄漏疏散能力分析

为研究燃气管线泄漏事故人员疏散能力,统计分析近年国内燃气泄漏典型事故,得出第三方违章作业施工为燃气泄漏事故比例最高的直接原因及燃气泄漏事故伤亡人数发展趋势,在此基础上,引入粒子群PSO算法,以某施工引起的燃气管线泄漏事故为实例,研究领导者的领导能力和应急处置能力对员工之间信息交流及人员应急疏散能力的影响。分析实例显示现场领导者学习因子偏低,指挥能力差,直接影响事故现场的应急疏散自救行为,甚至改变疏散路径。并进一步分析模拟得出,学习因子提高后,现场领导者和员工的信息更新与交换效率大幅提升,应急疏散能力随之提高,进而提出实用性对策措施和建议,为提升燃气管线泄漏事故应急疏散能力提供技术参考。     

Competing land uses and fossil fuel,and optimal energy conversion rates during the transition toward a green economy under a pollution stock constraint

We study the transition to a carbon-free economy in a model with a polluting non-renewable resource and a clean renewable resource. Transforming primary energy into ready-to-use energy services is costly and more efficient energy transformation rates are more costly to achieve. Renewable energy competes with food production for land and the food productivity of land can be improved at some cost. To avoid catastrophic climate damages, the pollution stock is mandated to stay below a given cap. When the economy is not constrained by the cap, the efficiency of energy transformation increases steadily until the transition toward the ultimate green economy; when renewable energy is exploited, its land use rises at the expense of food production; food productivity increases together with the land rent but food production drops; the food and energy prices increase and renewables substitute for non-renewable energy. During the constrained phase, the economy follows a constant path of prices, quantities, efficiency rates, food productivity and land rent, a phenomenon we call the ‘ceiling efficiency paradox’.     

The price of innovation: An analysis of the marginal cost of green buildings

Energy efficiency plays an important role in reducing the carbon externality from buildings, but economic analyses of more efficient, green building have thus far ignored input costs. This paper finds that the average marginal cost of green-labeled construction projects is smaller than the value premiums documented in the literature. However, design fees, representing just a fraction of development costs but paid largely up-front, are significantly higher for green construction projects. These projects also take longer to complete. The results provide some insight into the market barriers and market failures that may explain the relatively slow adoption of otherwise economically rational green construction practices.