地震灾害下城市供水网络韧性评估及优化研究

为提升城市供水网络应对地震灾害的能力,基于性能响应函数(PRF)方法,引入基础设施网络均衡理论,设计综合考虑城市供水网络物理状态和输送能力的性能时程响应函数,构建贯穿结构和功能双维度的地震灾害下城市供水网络韧性评估方法;从灾害概率、灾害后果、恢复速度、恢复程度等4个关键因素出发,提出城市供水网络网状扩张、管道延性改造、增加恢复资源和提升恢复储备等韧性优化策略;以我国华东某市供水网络为例,定量评估不同优化策略下的韧性提升效果,提出不同决策场景下恢复资源r和恢复储备b的优化配置方法。结果表明:管网延性改造是提升供水网络韧性的有效措施,网状扩张能提升供水网络性能,但对韧性提升无明显作用,网状扩张后要注意增加网络恢复资源和恢复储备。     

Water Network Synthesis Using Mutation-Enhanced Particle Swarm Optimization

Different techniques for the synthesis of industrial water reuse/recycle networks have been developed in recent process integration research. These tools range from graphical pinch analysis approaches to mathematical programming models. The latter have the advantage of being flexible enough to incorporate various water network constraints, but in many cases these are often non-linear, thus making the identification of global optima difficult. Recent work has demonstrated the effectiveness of metaheuristic algorithms such as particle swarm optimization (PSO), for finding good solutions these problems. This work describes the use of a modified PSO for solving mixed integer non-linear programming (MINLP) models for water network synthesis. By incorporating a mutation operator for the binary variables in the model, the algorithm is able to escape sub-optimal network topologies and proceed towards better solutions than can be found with ordinary PSO. Two case studies involving water recycle/reuse are used to demonstrate the new design methodology.     

Requirements for improved process hazard analysis (PHA) methods

In order to develop better process hazard analysis (PHA) approaches, weaknesses in current approaches first must be identified and understood. Criteria can then be developed that new and improved approaches must meet. Current PHA methods share common weaknesses such as their inability specifically to address multiple failures, their identification of worst-consequence rather than worst-risk scenarios, and their focus on individual parts of a process. There has been no comprehensive analysis of these systemic weaknesses in the literature. Weaknesses are identified and described in this paper to assist in the development of improved approaches. Knowledge of the weaknesses also allows PHA teams to compensate for them to the extent possible when performing studies.Key criteria to guide the development of improved methods are proposed and discussed. These criteria include a structure that facilitates meaningful brainstorming of scenarios, ease of understanding and application of the method by participants, ability to identify scenarios efficiently, completeness of scenario identification, exclusion of extraneous scenarios, ease of updating and revalidating studies, and ease of meeting regulatory requirements. Some proposals are made for moving forward with the development of improved methods including the semi-automation of studies and improvements in the training of team members.     

The role of people and human factors in performing process hazard analysis and layers of protection analysis

Process hazard analysis (PHA) and Layers of Protection Analysis (LOPA) studies address human failures in operating and maintaining processes and the human factors that influence them, amongst other types of failures. People perform PHA and LOPA studies and, therefore, such studies themselves are subject to various possible human failures. Much less attention has been paid to the human factors that influence the performance of PHA and LOPA studies than human factors that influence hazard scenarios. Human failures in the performance of PHA and LOPA studies should be of significant concern to practitioners as such studies are difficult and time-consuming activities that place significant demands on participants, which increases the chance that errors will be made. Human factors such as willingness to rely on the unsubstantiated opinions of others, groupthink, underestimation of the frequencies of low-probability, high-consequence events, and allowing a false sense of accomplishment to distract from implementing study results must be recognized and addressed.This paper identifies and discusses various human factor issues that can influence the quality of PHA and LOPA studies covering preparing for, conducting, recording, documenting, and following-up on studies. Guidelines are provided to help minimize the extent to which these human factor issues may impair study quality.     

RCNet: An optimisation software for the synthesis of resource conservation networks

RCNet is a spreadsheet-based software for the synthesis of resource conversation networks (RCNs) for planning the efficient use of material resources (e.g., water, utility gases, solvents) in industrial plants. The software is developed based on the well-established process integration tools, namely pinch analysis and mathematical programming techniques. In the first stage, pinch analysis is used to determine maximum resource conservation targets prior to detailed RCN design. In the second stage, mathematical optimisation is then used to determine the optimal flowrate allocation between process sources and sinks of the RCN, to achieve the performance targets. RCNet is applicable for various industrial applications. To date, no generic software has been developed to handle water minimisation, hydrogen recovery and property integration, which is the main subject of this work. In the developed software, same interface and platform can be used to solve abovementioned problems independently. For illustration, three literature examples on water minimisation, hydrogen recovery and property integration, as well as an industrial case study are solved using RCNet.     

协作网络在跨区域灭火应急救援中的应用研究

为有效解决跨区域灭火应急救援工作中统一指挥难、行动协调难、资源调配难和协同效应难等问题,基于网络在跨区域管理工作中的重要性以及协同原理理论,提出跨区域灭火应急救援协作网络的概念,并分析跨区域灭火应急救援协作网络在跨区域灭火应急救援工作中的功能与作用,最后提出了跨区域灭火应急救援协作网络的结构框架及运行机制。结果表明:协作网络与跨区域灭火应急救援工作相结合具有重要意义,今后的工作重点应是研究构建跨区域灭火应急救援协作网络的影响因素、可行性、实用性以及相关配套设施和宏观运行环境等。     

Optimal Assignments of Allocating and Scheduling Emergency Resources to Accidents in Chemical Industrial Parks

Accidents in chemical industrial parks can result in mass casualties and the risk usually escalates due to domino effects. However, most of the existing models of emergency logistics do not account for domino effect and may be unsuitable for emergency response to accidents in chemical industrial parks. This paper presents a mathematical model proposed for optimal assignments of allocating and scheduling emergency resources for rescuing victims and preventing accident spreading simultaneously. The detailed characteristics of accident scenarios and emergency resources are taken into account. Based on this, the efficiency of emergency response is evaluated by the total number of fatalities and the amount of losses caused by domino effects which are the optimal objectives of the model. A numerical case study was conducted by solving the model using a designed heuristic algorithm. The results showed the applicability and reliability of the proposed model for making optimal assignments for emergency response to accidents in chemical industrial parks.     

Smart chemical industry parks in China: Current status,challenges, and pathways for future sustainable development

The chemical industry has been pivotal to the rapid economic expansion and high standards of living in China. As an important carrier of the chemical industry, China has designated as many as 723 chemical industrial parks (CIPs). Unfortunately, safety concerns have become an obstacle to the sustainability of China's CIPs. Ever since the two devastating hazardous chemical accidents, namely “Tianjin Port 8·12 Explosion” and “Jiangsu 3·21 Explosion,” which occurred in 2015 and 2019 respectively, China has prioritized the safety of CIPs. The smart chemical industrial parks (SCIPs) are considered the optimal strategies toward the goal of sustainable development in China's CIPs. However, there has been a lack of research and subsequent discussion on the role of SCIPs in the forthcoming years. The period between 2020 and 2025 is considered a crucial period for the future development of CIPs and SCIPs in China mainly because the country has released a series of important government documents and national standards (such as “Fourteenth Five-Year (2020–2025) Plan for Hazardous Chemical Safety” and “Guidelines of SCIPs construction”) to promote hazardous chemical safety. With the aim of analyzing the future sustainable development for the construction of SCIPs in China, this paper proposes a systematic methodology in order to conduct an integrated and in-depth review on the standardization construction status (framework with Chinese characteristics, key events, spatial features, and national pilots), future tasks, problems, and sustainable development pathways of China's SCIPs. The method is implemented in accordance with the current scenarios of hazardous chemical safety in China and the latest government documents, regulations, and standards. Furthermore, this study provides basic data and a basis for future studies associated with the safety and sustainability of the SCIPs construction and chemical industry, both within China and in other countries.     

Bi-level fuzzy optimization approach for water exchange in eco-industrial parks

In order to minimize the consumption of resources and the generation of waste, eco-industrial parks (EIPs) have been designed to encourage the establishment of waste exchange networks between the plants contained within them. Considering that the participating plants have their individual fuzzy cost goals and that the park authority has the objective of minimizing total freshwater consumption in the EIP, this problem may be formulated as a bi-level optimization problem, with the park authority as the upper-level decision-maker. A bi-level fuzzy optimization model is developed to explore the effect of charging fees for the purchase of freshwater and the treatment of wastewater in optimizing the water exchange network of plants in an EIP. The effect of subsidizing exchange of streams between plants is also included in the model. Results show that it is not necessary to impose exorbitant fees, nor to completely subsidize costs associated with recycling, in order to induce significant reduction of the consumption of freshwater in the EIP.     

Performance evaluation of a water mist system in semiconductor wet bench fires

Wet benches are typically utilized in semiconductor facilities for wafer and parts cleaning. Heaters and some flammable liquids, such as acetone and isopropyl alcohol (IPA), are employed during the cleaning process. Wet bench fires have caused serious losses in the semiconductor industry. To assess the fire protection performance, several field tests were performed using a water mist system installed in the wet bench. In this study, acetone pan fuel was used as fire source. The test parameters were operational pressure, pan size, nozzle location, cylinder obstruction and degree of door closure. An appropriate design for operating pressure and the location of water mist nozzles extinguished wet bench fires effectively in the early fire stages. The nozzles are suggested to be fixed above or on the each side of the pan, ensuring that mist can completely cover a pan surface with sufficient momentum. With this suggested design, fires can be extinguished in the pan and do not spread over the wet bench.     

Exploring oil and gas industry workers’ knowledge and information needs

Many incident reports and much research literature have concluded that incident rates in high-hazard industries can be reduced by enhancing the knowledge and information sources available to workers. However, a sparsity of published research reporting workers' perspectives on the value of information and knowledge sources in different operational situations potentially limits the effectiveness of interventions aimed at improving human responses to process safety performance. In response, this work seeks to understand how frontline oil and gas industry workers, responsible for managing process safety and other risks in their hazardous workplaces, rely on their own knowledge, the knowledge of others and information provided to manage different operating scenarios. A set of open and closed-ended survey questions were distributed to workers at several upstream and downstream oil and gas companies. Statistical analysis of 133 responses revealed interesting insights relating to participants’ experience levels, decision making practices and perceptions on the importance of various information and knowledge sources in different operating circumstances. The data revealed differences in the sources of knowledge relied upon by experienced and less experienced workers. Experienced workers rely on their own knowledge in both routine and potentially high-impact scenarios. Less experienced workers also rely on their own knowledge for routine decisions however they reported seeking out external knowledge and information in potentially high-impact scenarios. The data suggests that interventions to improve safety by enhancing the availability of knowledge and information sources are less likely to affect experienced workers and alternate strategies might be needed. However, such interventions might be effective if they are focused on supporting newer workers.     

Safety investment optimization in process industry: A risk-based approach

Process plant safety is a critical indicator of organizational performance. Adequate investment into safety practices to avoid future accident cost is therefore a beneficial strategy. The current approach to such investments in the process industry is driven largely by simple risk-based heuristics, insurance market premiums, organizational culture and management judgment. There is, however, an absence of an overarching methodology to assist such an effort. Therefore, there is a need for developing a robust decision-making framework for enabling systematic and optimal allocation of financial resources across all significant risk elements within a process plant.The present work proposes a safety investment optimization (SIO) framework for a typical process plant. Such an optimization approach targets maximal reduction of risk values across all potential hazards within the constraint of a given safety investment budget at the incipient stage of establishing a plant such that it saves future cost to company by reducing the risk from accidents. At the same time the framework takes into account the need to comply with the regulatory requirements imposed by the government. Additionally, access to insurance market as a strategy to transfer risk is also integrated. Finally, the residual risks are managed through investments in selective safeguards while ensuring that the benefits over-weigh the cost of such an exercise. For illustrating the application of the framework, a representative process plant with a select number of risk scenarios is chosen and all steps suggested by the framework are demonstrated quantitatively. It is anticipated that the proposed SIO framework will help optimal resource allocation for managing the risks implicit in a typical process plant.     

考虑多主体心理效应的应急资源调度超网络模型

为探究不同人员主体心理效应对应急资源调度过程的影响,运用超网络工具,定量描述差异化应急主体协调运作下不同属性应急网络的相互作用;同时,针对实际调度过程中出现的供需矛盾,引入行为科学理论,量化表示决策者后悔和灾民失望心理,并将其融入到应急资源优化调度问题中;建立以调度时间、应急成本、救援效应为目标函数的应急资源调度超网络模型,将模型转化为变分不等式等价形式,应用修正投影算法对模型进行求解。结果表明:该模型可有效解决多人员主体心理作用下的应急资源协调调度问题;应急主体关联度、灾害风险度、决策者后悔心理和后悔规避行为以及灾民失望心理和失望规避行为对应急资源调度方案的制定有着重要的影响。     

用电凝聚装置去除废水中重金属离子

用一种新型电极结构的电凝聚装置,对废水中的重金属离子进行了去除实验研究.并对影响重金属离子去除率的各种因素进行了分析.结果表明,使用该装置在适当的实验条件下,可以有效去除废水中的Zn2+、Cd+2、Pb+2、Hg2+和Cu+2,使之达到达标排放或回用水平.该装置具有结构简单,自动化程度高,操作简便,占地面积小,污泥产量小的特点.     

Ontology-based computer aid for the automation of HAZOP studies

Hazard and Operability (HAZOP) studies are conducted to identify and assess potential hazards which originate from processes, equipment, and process plants. These studies are human-centered processes that are time and labor-intensive. Also, extensive expertise and experience in the field of process safety engineering are required. There have been several attempts by different research groups to (semi-)automate HAZOP studies in the past. Within this research, a knowledge-based framework for the automatic generation of HAZOP worksheets was developed. Compared to other approaches, the focus is on representing semantic relationships between HAZOP relevant concepts under consideration of the degree of abstraction. In the course of this, expert knowledge from the process and plant safety (PPS) domain is embedded within the ontological model. Based on that, a reasoning algorithm based on semantic reasoners is developed to identify hazards and operability issues in a HAZOP similar manner. An advantage of the proposed method is that by modeling causal relationships between HAZOP concepts, automatically generated but meaningless scenarios can be avoided. The results of the enhanced causation model are high quality extended HAZOP worksheets. The developed methodology is applied within a case study that involves a hexane storage tank. The quality and quantity of the automatically generated results agree with the original worksheets. Thus the ontology-based reasoning algorithm is well-suited to identify hazardous scenarios and operability issues. Node-based analyses involving multiple process units can also be carried out by a slight adjustment of the method. The presented method can help to support HAZOP study participants and non-experts in conducting HAZOP studies.     

基于灾变的人群疏散避灾路径优化及应用

突发事件条件下的应急疏散是一个复杂的过程,不仅要考虑时间因素,而且要考虑疏散网络中各路段的受灾风险水平。因此,对于人群快速转移避灾路径的解算结果,不仅要求快速,还要求避灾。基于灾害预测的疏散路径优化理论模型,在求解时变灾害条件下,集成考虑实时与未来灾害影响的转移避灾路径优化算法。采用C#程序设计语言和Visual studio 2013平台,开发了进行模型算法实现的原型系统,并通过算例进行了说明。结果表明:在预先设置的灾害情景中,提出的模型算法可以提前规划出避开灾害且疏散时间较短的路径,为制定应急预案提供参考依据。     

工业锅炉烟管氯离子腐蚀原因分析

某DZL(SG)-1.25-M、Q-Ⅱ型工业锅炉的烟管水侧出现大量腐蚀凹坑,腐蚀烟管更换后不足一个月,烟管再次出现明显的腐蚀倾向.试验分析表明:水处理交换树脂清洗不彻底引起给水氯离子偏高,排污不足导致锅水中的氯离子和溶解固形物进一步浓缩,溶解固形物高于标准GB/T 1576-2018要求,受热烟管水侧外壁最终在锅水高浓度氯离子作用下发生了电化学腐蚀.     

Setting optimal operating conditions for a catalytic reactor for butane oxidation using parametric sensitivity analysis and failure probability indices

Safe operation of a catalytic reactor remains a sensitive issue when highly exothermic reactions are conducted and hazardous side reactions may occur. Derivation of the optimal operating conditions must include economic but also safety criteria, technological constraints, beside controllability and stability aspects. The present work introduces a criterion based on a joint failure probability index related to uncertainty in the runaway boundaries and the random disturbances of the operating parameters. The use of such a safety criterion is even more important when setting the optimal operating policy of the reactor in the vicinity of the runaway boundaries that often correspond to a high productivity. The paper indicates how an economically efficient but more prudent operating policy can be selected, by simultaneously considering the economic and safety objectives. An example is provided for the case of an industrial fixed-bed tubular reactor, of high thermal sensitivity, used for the catalytic oxidation of butane to maleic anhydride in vapour phase. The multi-objective optimization can lead to a prudent trade-off operating solution (corresponding to a failure probability of maximum 3–4%) that limits the reactor productivity. Being based on a local and global sensitivity analysis of the reactor, the proposed rule is generally applicable by minimizing the probability with which control variables violate their safety limits.