System dynamics research of non-adaptive evacuation psychology in toxic gas leakage emergencies of chemical park

Chemical industry park plays an important role in optimizing the allocation of resources, but an emergency may make a great deal of personnel casualty and property loss. Many casualties are not the result of accidents but are caused by extreme behavior because of the non-adaptive psychology of the evacuees. Panic is one of the non-adaptive psychological behaviors during an evacuation, which is influenced by a variety of factors. Based on the consideration of the disaster environment and the evolution of crowd emotion, a system dynamics model of panic spread is established by using Anylogic software, and simulation experiments are carried out for different disaster severity, visibility, and groups. The results show that the number of people with severe panic increase when visibility decreases or disaster diffuses. Besides, the appropriate proportion of groups can effectively reduce the cooling time of crowd and ease the fears. However, continue to increase the number of groups has no significant effect on the panic control. This work can provide some reasonable guidance for regional emergency evacuation in chemical park.     

基于EFDC的长江常州段污水排江浓度场数值模拟

长江感潮河段水流与污染排放引起的浓度场复杂多变,基于EFDC(Environmental Fluid Dynamic Code)模型,采用正交曲线网格拟合自然河道边界,建立了长江常州段的水动力和水质模型。采用现场同步实测资料,与计算结果比对,证明该模型在水动力和水质两个方面都与实测数据吻合较好,满足了实际工程的需要;同时由于长江水流运动较快,一阶降解动力学已经满足了化学需氧量(COD)、氨氮(NH3-N)和总磷(TP)浓度计算要求,可以不考虑它们复杂的生化反应过程。     

大气细颗粒物在线源解析方法研究进展

基于对国内外关于PM2.5化学组分特征、二次气溶胶生成机理、源解析模型的研究综述,引入实现PM2.5在线源解析的2种可能方法,即气溶胶质谱+解析算法与3类化学组分组合观测+受体模型。重点阐述了气溶胶质谱及在线水溶性离子、EC/OC和金属元素仪器的应用研究现状,并分析了不同仪器测定结果的可靠性、优势及缺陷,在此基础上提出加强城市尺度的大气化学二次反应机理及关键技术参数研究、大气颗粒物化学组分连续观测应用于在线源解析的研究、基于多种信息来源和技术手段的在线源解析方法集成研究等建议。     

Biosorption of zinc(II) on rapeseed waste: Equilibrium studies and thermogravimetric investigations

The removal of heavy metals from aqueous effluents so as to avoid their toxic, bioaccumulation and biomagnification effects to humans and environment is usually realized by means of physical, chemical treatment, and biological processes. The aim of this study is to evaluate the potential of rapeseed waste from biodiesel production as a biosorbent for Zn(II) ions.The ability of the rapeseed waste for Zn(II) biosorption exhibited a maximum at pH 4.5–5. The removal efficiency of Zn(II) from solution with an initial concentration of 72 mg L⁻¹ varied from 39% to 89% for an increase of the rapeseed waste dose from 2 to 30 g L⁻¹. The amount of Zn(II) retained on the tested rapeseed increased with increasing metal ion concentration, but the Zn(II) sorption percentage decreased. The equilibrium data are fitted to the Langmuir isotherm better than to the Freundlich isotherm. The kinetics of Zn(II) biosorption process follows a pseudo-second order model. The thermal stability of the rapeseed before and after Zn(II) biosorption was studied by thermogravimetric analysis. It was found that the zinc loaded rapeseed exhibits a better initial thermal stability than the original rapeseed, presumably due to the cross linking generated by the intermolecular complexation of Zn(II) ions. In both cases, the thermal decomposition takes place according to some reassembling kinetic models, in two phases with order n reactions. The results of this study strongly suggest the possibility to use rapeseed as an effective biosorbent for Zn(II) ions removal from aqueous effluents (municipal/industrial wastewaters).     

Justice for Bhopal! And No More Bhopals! Three decades of national and international campaigning

Dissatisfaction with the responses of the responsible corporation, Union Carbide, and the Indian government to Bhopal resulted in a campaign by national and international NGOs (non-governmental organisations) over the past three decades. While initially the Indian and international campaigns were separate, over time greater international cooperation took place. In the immediate aftermath of the disaster local NGOs prioritised health, justice and rehabilitation issues, while international NGOs used Bhopal to question chemical industry process and environmental safety in their own countries, as well as internationally. Indian NGOs called on international NGO resources to gain legitimacy for their campaign, to use NGOs as proxies and to extend the geographical scope of the campaign, while international NGOs used Bhopal as an example to advance NGOs analyses and policies. Over the period of the campaign, Indian NGOs became more sophisticated in their campaigning. The international campaign has increasingly become an online campaign, involved in an image or reputational war with Dow Chemical, which took over Union Carbide, while the original campaign issues of justice and reparations over the process safety disaster were joined by similar issues related to environmental safety of abandoned toxic waste.     

Uncertainties in QRA: Analysis of losses of containment from piping and implications on risk prevention and mitigation

Quantitative Risk Assessment (QRA) is commonly used in the chemical industry to support decision-making. Common practices are based on standard methods, such as fault tree, event tree, etc.; in this frame, risk is a function of frequency of events (probability) and associated consequences (negative outcomes), but relevant uncertainties often are not properly taken into account in the derived results. This paper presents the application of an extended risk analysis of loss of containments for a case-study with the following aims: firstly, the uncertainties related to the results of the analysis, which derive from assumption in the application of the standard models, are qualitatively assessed; secondly the application allows evaluating the impact of the uncertainties on the trustworthiness of the results and, finally, commenting about their use in the risk prevention and mitigation.     

Location selection of emergency supplies repositories for emergency logistics management: A variable weighted algorithm

With the development of the city, the number of establishments that are proposed or under construction is increasing year by year, and if they are industries that handle flammable, explosive, toxic, harmful, and dangerous substances, the public safety will face great threats, which will bring great challenges to emergency rescue work. Therefore, providing reasonable solutions to the problem of location selection of emergency supplies repositories are necessary for improving the emergency response efficiency in chemical industrial parks. A mathematical model for location selection of emergency supplies repositories in emergency logistics management are presented considering more actual factors. The optimization objectives of the model are to minimize total transport length and cost. And then a Variable Weighted Algorithm is designed to solve the model, where an auxiliary function was constructed with different methods of building weighting factors based on the theory and method of solving multi-objective optimization problems in operational research. Simulation results show the effectiveness and feasibility of the models and algorithms presented in this paper.     

好氧触媒在造纸法再造烟叶污水处理中的应用分析

本文围绕好氧触媒在造纸法再造烟叶污水处理中的应用展开分析。如对好氧触媒在再造烟叶污水处理中的应用必要性及好氧触媒作用原理予以介绍,并对好氧触媒在造纸法再造烟叶污水处理中应用展开试验。     

Hierarchical pre-positioning of emergency resources for a chemical industrial parks concentrated area

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.     

Assessment of the effect of technical and management characteristics on the frequency of release from piping: An application to a gas storage facility

The assessment of the frequencies of release from piping due to losses of containment is an essential step in the preparing Safety Reports, drawn up as required by the so-called “Seveso” Directive. These are usually calculated starting from the frequencies of random rupture included in international databases and are not plant-specific, furthermore, the quantification of the effect of the safety management system of the facility is not easy. A simple and flexible approach quantifying technical and management characteristics of the plant has been proposed by Milazzo and co-workers in 2010; it is based on the modification of the frequency taken from literature, through the use of the percentages of failure causes actually possible in that plant, and the judgment about their management. The data about the failure causes are taken from the literature and modified by using corrective factors to adapt them to the industrial context. To make possible the application of the method to a large number of major-hazard industry types, some aspects of the approach needed to be improved; these have been identified during a development project coordinated by RINA Consulting, on behalf of Saipem, with the collaboration of the University of Messina. The improvement of the approach focused on two main points, the development of a method to calculate the corrective factors for the failure causes associated with corrosion and erosion phenomena and the strengthening of the methodology for the formulation of the judgment about the safety management. This paper illustrates the fully improved method, as well as an application to a typical gas storage plant.