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941.
This study investigated a 2010 fire and explosion that occurred at a polypropylene (PP) and copper-clad laminate high-tech plant in Taiwan. Liquid acetone leakage caused the fire and explosion. One person was killed and five were injured; property damage was estimated at US$20 million. In contrast to conventional plants, high-tech plants have sophisticated instrumentation, highly complex pipelines, and confined spaces. In addition, the floor area in a high-tech plant is large and frequently contains a channel through the ground floor to the second or third floor. This channel design enables the fire compartment to be destroyed. Therefore, the system cannot confine the fire to a specific area, thus hindering fire-relief operations. In this study, the original fire outbreak occurred in the PP processing area on the ground floor. The acetone storage tank was located on the third floor. The investigation conducted at the fire site of the situations of the burning (bursting) loss determined that the acetone liquid leaked and dripped from floor cracks and tunnel oven to the PP processing area. Because the PP manufacturing process rapidly generates static electricity, the flammable liquids made contact with the source of ignition, which caused the explosion and fire. Various procedures, such as those involving the operating environment of production, packaging, and processing in a high-tech plant, are likely to produce static electricity in a workplace. Improved electrostatic management can prevent the loss of property and lives, liquid acetone leakage, and loss of equipment caused by static electricity fire. 相似文献
942.
The paper represents some results of comparative analysis of the methods used for processing and interpreting data of adiabatic calorimetry as well as applying it to practical situations. Specifically two approaches are compared – approximate method based on evaluation of simplified kinetics and a more comprehensive, simulation-based method that utilizes the evaluation of more detailed kinetic models.The analysis is focused on two important types of data processing – correction of experimental results on thermal inertia (phi-factor correction) and estimation of adiabatic time to maximum rate (TMR).The most widely cited method for phi-factor correction is considered and its improvement is proposed to enable more precise prediction of the adiabatic time scale. A procedure for phi-factor correction of pressure response is also proposed. The limitations of this enhanced Fisher's method are discussed by comparison with simulation-based method. All the illustrative materials are based on real examples.As an example of application, the simplified method will be used to predict TMR and its limitations will be discussed. 相似文献
943.
LEED绿色建筑评价体系是目前国际上最具权威性的绿色建筑评价标准,由美国绿色建筑委员会制定并推行.在结合国内施工阶段现状的基础上,寻找LEED绿色建筑评价体系中与施工阶段的契合点,针对相关要求采取措施,最终达到节能、环保、可持续的目的.表1,参6. 相似文献
944.
This study was performed to investigate the removal of phosphate from domestic wastewater using a modified steel slag as the adsorbent. The adsorption effects of alkalinity, salt, water,and thermal modification were investigated. The results showed that thermal activation at 800℃ for 1 hr was the optimum operation to improve the adsorption capacity. The adsorption process of the thermally modified slag was well described by the Elovich kinetic model and the Langmuir isotherm model. The maximum adsorption capacity calculated from the Langmuir model reached 13.62 mg/g. Scanning electron microscopy indicated that the surface of the modified slag was cracked and that the texture became loose after heating. The surface area and pore volume did not change after thermal modification. In the treatment of domestic wastewater, the modified slag bed(35.5 kg) removed phosphate effectively and operated for 158 days until the effluent P rose above the limit concentration of 0.5 mg/L. The phosphate fractionation method, which is often applied in soil research, was used to analyze the phosphate adsorption behavior in the slag bed. The analysis revealed that the total contents of various Ca–P forms accounted for 81.4%–91.1%, i.e., Ca10–P 50.6%–65.1%, Ca8–P 17.8%–25.0%,and Ca2–P 4.66%–9.20%. The forms of Al–P, Fe–P, and O–P accounted for only 8.9%–18.6%. The formation of Ca10–P precipitates was considered to be the main mechanism of phosphate removal in the thermally modified slag bed. 相似文献
945.
南京市雨污分流改造经过多年建设施工,基本上从源头上实现雨污分流,避免污水溢流入秦淮河。初期雨水造成的城市非点源污染是受纳水体的重要污染源,在一些实施了分流制排水系统的城市,经过一段时间的运行,周边水体的污染情况改善不是十分明显。白下区雨污分流改造后,为避免初期雨水对内秦淮河污染,以大中桥泵站北截流沟为例,探讨在沿河截流井设提升泵弃流初期雨水,利用现状截流沟蓄水,结合规划改造大中桥泵站新建蓄水池,为今后雨水利用提供条件。 相似文献
946.
绿色大学是在日益严重的环境问题背景下生态文明和社会可持续发展理念融合于校园的必然趋势.作为技术传承和创新的主体,积极探索和深化高校能源改革具有非常重要的意义.本文以中国石油大学的面板数据作为数据研究基础,结合气候能源因素,提出基于综合节能模型的绿色大学构想,采用簇聚类和遗传优化进行能源整合,动态评估后进行系统参数加权优化,从而达到能源优化使用的目标.实践表明,该模型有效提升能源效率和改善环境,具有重要的应用意义. 相似文献
947.
针对高校能源消耗建模研究与应用问题,文中介绍了高校能耗日益增长现状,给出了高校能耗模型构建,为节约能源必须做好精准能耗预测.建立了灰色径向基函数神经网络高校能耗预测模型,并采用基于排序等分法赌盘规则选择算子的遗传算法对该模型进行全局优化,进一步用实例对比分析评估了模型的有效性.实践表明,优化后的模型能有效预测能耗,与传统单一的建模方式相比,有更好的拟合性、稳定性、预测精度和更快的收敛速度,为节能评估和设计提供了决策依据. 相似文献
948.
MnxCe1- xO2(x: 0.3–0.9) prepared by Pechini method was used as a catalyst for the thermal catalytic oxidation of formaldehyde(HCHO). At x = 0.3 and 0.5, most of the manganese was incorporated in the fluorite structure of Ce O2 to form a solid solution. The catalytic activity was best at x = 0.5, at which the temperature of 100% removal rate is the lowest(270°C). The temperature for 100% removal of HCHO oxidation is reduced by approximately 40°C by loading 5 wt.% Cu Oxinto Mn0.5Ce0.5O2. With ozone catalytic oxidation, HCHO(61 ppm) in gas stream was completely oxidized by adding 506 ppm O3 over Mn0.5Ce0.5O2 catalyst with a GHSV(gas hourly space velocity) of 10,000 hr-1at 25°C. The effect of the molar ratio of O3 to HCHO was also investigated. As O3/HCHO ratio was increased from 3 to 8, the removal efficiency of HCHO was increased from 83.3% to 100%. With O3/HCHO ratio of 8, the mineralization efficiency of HCHO to CO2 was 86.1%. At 25°C, the p-type oxide semiconductor(Mn0.5Ce0.5O2) exhibited an excellent ozone decomposition efficiency of 99.2%,which significantly exceeded that of n-type oxide semiconductors such as Ti O2, which had a low ozone decomposition efficiency(9.81%). At a GHSV of 10,000 hr-1, [O3]/[HCHO] = 3 and temperature of 25°C, a high HCHO removal efficiency(≥ 81.2%) was maintained throughout the durability test of 80 hr, indicating the long-term stability of the catalyst for HCHO removal. 相似文献
949.
950.
夏金兵 《安全.健康和环境》2014,14(6):49-51
针对苯储罐区所处的区域位置及火灾爆炸危险性,运用道化学火灾、爆炸危险指数法对苯储罐区的火灾、爆炸风险进行分析评价,得出其安全措施补偿前后的火灾、爆炸指数,确定危险等级,并提出了预防火灾爆炸事故的对策措施。 相似文献