爆炸超压场景下危化品社会风险对允许规划人口密度的影响分析*

为研究危化品重大危险源基于社会风险基准的规划管控影响,采用我国标准规定的定量风险评价方法,TNT当量炸药简化方法,针对最大TNT当量炸药、事故发生总累计频率、人口密度分布控制参数等不同工况条件,对比分析国土开发强度的允许人口密度受社会风险约束影响的变化规律。研究结果表明:人口密度指数分布控制参数Nk与Nb的允许取值随最大TNT当量炸药和事故发生总累计频率降低而提高;确定工况下,允许总人口规模受最大TNT当量炸药影响很小;在最大TNT当量炸药大于100 t或事故发生总累计频率小于1×10-8次/a时可按最大事故场景进行规划控制分析。     

基于后果的土地利用安全规划方法在化工园区的应用

土地利用安全规划是预防和控制重大工业事故的重要手段，本文讨论国外常见重大危险源土地利用规划的三种方法，给出一个基于后果的土地利用安全规划的方法。提出火灾、爆炸和毒物泄漏等事故场景下的伤害阈值标准并以此进行事故后果伤害分区，给出脆弱性目标的分级原则，最终给出土地利用安全规划的判断准则。以南方某化工园区为实例应用此方法进行分析研究。本方法可应用于重大危险源或化工园区的安全规划、安全评价以及应急规划等工作。     

Societal risk assessment of major hazard installations using QuickRisk

QuickRisk is a quantitative risk assessment tool developed at the Health and Safety Laboratory for use in assessing societal risk around onshore major hazard installations to inform land-use planning decisions. It uses release scenario information, parameterised consequence models, weather data, and population data from the National Population Database (NPD).This paper describes enhancements to the NPD methodology to include workplace populations. It describes the novel numerical, graphical and geographical representations of societal risk produced by QuickRisk. F–N data are analysed in terms of scenario FN curves and Delta PLL vs. N curves, where PLL is potential loss of life. The Delta PLL curves could be useful for comparison of FN curves against FN criterion lines or other FN data on a PLL basis. Geographical representations generated from PLL density maps show: the distribution of PLL dominating release scenarios or the percentage of risk contributed by the PLL-dominant release scenario, the maximum number of fatalities associated with the worst-case event, and the associated release scenario. Geographical representations are also generated of the maximum population that would meet a PLL density criterion, and the relative population change that would match a given PLL density criterion.These novel representations of societal risk could be useful for more effective communication between stakeholders on the risk levels in the vicinity of major hazard installations.     

RAPID-N: Rapid natech risk assessment and mapping framework

Natech accidents at industrial plants are an emerging risk with possibly serious consequences. For the mitigation of natech risk, authorities need to identify natech prone areas in a systematic manner. In order to facilitate probabilistic natech risk mapping, a unified methodology was developed that is based on the estimation of on-site natural hazard parameters, determination of damage probabilities of plant units, and assessment of probability and severity of possibly triggered natech events. The methodology was implemented as an on-line, extensible risk assessment and mapping software framework called RAPID-N, which allows rapid local and regional natech risk assessment and mapping with minimal data input. RAPID-N features an innovative data estimation framework to complete missing input data, such as on-site natural hazard parameters and plant unit characteristics. The framework is also used for damage assessment and natech consequence analysis, and allows easy modification of input parameters, dynamic generation of consequence models according to data availability, and extension of models by adding new equations or substituting existing ones with alternatives. Results are presented as summary reports and interactive risk maps, which can be used for land-use and emergency planning purposes by using scenario hazards, or for rapid natech consequence assessment following actual disasters. As proof of concept, the framework provides a custom implementation of the U.S. EPA's RMP Guidance for Offsite Consequence Analysis methodology to perform natech consequence analysis and includes comprehensive data for earthquakes. It is readily extendible to other natural hazards and more comprehensive risk assessment methods.     

危险工业设施周边土地利用规划研究

由于工业设施的存在,其周边区域常常受到潜在工业事故的威胁,为了减小这种风险,必须对这些区域进行合理的土地利用规划。借鉴欧洲研究者的研究方法,利用基于后果的风险评价方法确定不同破坏分区的边界,并将不同土地利用类型的脆弱等级引入土地利用规划,结合二者的结果,依据决策矩阵得到规划决策意见。通过将上述方法应用在某拟建的LPG中转站周边区域,以丙烷泄漏引起的沸腾液体蒸气爆炸为例,将风险分析和决策结果显示在地理信息系统上。案例分析表明该设施对周边区域影响较大,需要对其进行重新选址。     

LNG as a potential alternative fuel - Safety and security of storage facilities

The aim of this article is to summarize the safety and security aspects of storing of Liquefied Natural Gas (LNG) as a potential alternative fuel. The contribution deals with possible scenarios of accidents associated with LNG storage facilities and with a methodology for the assessment of vulnerability of such facilities. The protection of LNG storage facilities as element of critical infrastructure should also be a matter of interest to the state. The study presents the results of determination of hazardous zones around LNG facilities in the event of various sorts of release. For calculations, the programs ALOHA, EFFECTS and TerEx were used and results obtained were compared. Scenarios modelled within this study represent a possible approach to the preliminary assessment of risk that should be verified by more detailed modelling (CFD). These scenarios can also be used for a quick estimation of areas endangered by an incident or accident. The results of modelling of the hazardous zones contribute to a reduction in risk of major accidents associated with these potential alternative energy sources.     

Risk evaluation in Dutch land-use planning

In Dutch external safety policy, the acceptance of risk for the population in areas surrounding hazardous substances establishments is based on a limit value for individual risk (IR). Additionally, changes to societal risk (SR) must be justified. A specific software program (SAFETI-NL) with the associated Reference Manual Bevi Risk Assessments (RIVM, 2009) is legally required for the calculation of IR and SR. This prescribed “Bevi calculation method” forms the basis for decisions with important consequences for industry, land use planning and the protection of citizens. It is important that the outcome of calculations made with the prescribed method can be relied upon when making decisions about land use planning that affects both industry and population. This is the subject of this paper.The prescribed calculation method has been evaluated by performing a case study. The evaluation focussed on risk modelling of a Boiling Liquid Expanding Vapour Explosion (BLEVE) at an LPG filling station, an incident type that plays a significant role in Dutch external safety. The risk modelling of the BLEVE with the prescribed calculation method was found to have a number of serious deficiencies. It is concluded that the prescribed calculation method yields no reliable perspective on the safety of production, use and storage of hazardous substances, nor of possibilities to increase safety.Decision making should not only depend on quantification of IR and SR. Improving the safety-relevance of the prescribed calculation method requires an increase of the number of dimensions of the outcome of risk calculations in order to make feedback possible. It is recommended to incorporate additional, safety-relevant information into planning and decision-making processes. It is envisaged that a more far-reaching change of Dutch QRA practice is needed (medium to long term). In this context, a number of interesting elements have been noticed in decision-making procedures in other EU Member States.     

重大危险源区域风险评价及监管对策

结合目前重大危险源事故频发的安全生产形势,分析了石油化学工业发展和城市化进程加快所带来的城市区域高风险,阐明了进行区域风险评价和重大危险源监管的必要性.现有区域风险定量评价方法主要有两个主流,分别为基于个人风险和社会风险的方法和基于风险补偿的方法.概要阐述了两种方法的基本原理、评价程序和最终得到的区域风险效果图,对比分析了两种区域风险定量评价方法的适用性.最后从区域规划阶段、运作阶段和应急阶段分别提出了强化重大危险源监管的对策,并阐述了重大危险源区域风险评价和监管的保障机制,以期能够对重大危险源集中区域的规划和监管提供相关的技术支持.     

Aspects of risk analysis associated with major failures of fuel pipelines

This paper presents a methodology of risk assessment for hazards associated with transportation of dangerous substances in long pipelines. The proposed methodology comprises a sequence of analyses and calculations used to determine basic reasons of pipeline failures and their probable consequences, taking individual and societal risk into account. A specific feature of this methodology is a combination of qualitative (historical data analysis, conformance test and scoring system of hazard assessment) and quantitative techniques of pipeline safety assessment. This enables a detailed analysis of risk associated with selected hazard sources by means of quantitative techniques. On the ground of this methodology typical problems that usually pose serious threat and constitute part of risk analysis for long fuel pipelines are also presented. To verify above methodology, complete risk analysis was performed for the long distance fuel pipeline in Poland.     

Semi-quantitative risk assessment of commercial scale supply chain of hydrogen fuel and implications for industry and society

This paper is derived from a study on the safety of bulk transport and storage of hydrogen as a fuel, carried out by the Health and Safety Laboratory (HSL) for the Department for Transport (DfT). The aim of the study was to identify the knowledge and data required to develop fully a risk assessment for a hydrogen delivery and storage infrastructure. The methodology used was to begin to carry out a risk assessment for a representative delivery and storage supply chain, using a risk assessment methodology commensurate with the availability of necessary data. Semi-quantitative risk assessment was carried out through top-down HAZID brainstorming, consequence modelling using commercially available software, and use of a risk matrix.Finally through the risk assessment carried out and relevant literature review, the gaps in hazard identification, consequence modelling and frequency assessment, which should be filled to develop a quantified methodology, were compiled.Using data for current UK LPG consumption, comparisons were made between hydrogen and LPG for mode of failures and number of trips required to supply equivalent energy demand. The implications of using ammonia as a hydrogen carrier (hydrogen is within the ammonia molecule) and regulatory implications on hydrogen fuelling or storage sites are also discussed.     

长株潭城市群核心区重大危险源安全规划研究

笔者结合《长株潭城市群区域规划》,从城市的安全功能区划、重大危险源辨识、重大危险源安全规划对象、风险评价、风险控制等5个方面,初步探讨该市重大危险源安全规划的一般方法和技术要点,初步提出长株潭核心区重大危险源安全规划的编制程序的构想:①重大事故的统计分析和基础资料调查;②确定重大危险源和区域性重大事故风险评价;③确定安全功能区划,提出各类规划对象可接受的风险标准;④确定整治规划方案及实施措施。     

Risk assessment methodology for high-pressure CO2 pipelines incorporating topography

This paper presents a risk assessment methodology for high-pressure CO₂ pipelines developed at the Health and Safety Laboratory as part of the EU FP7 project CO2Pipehaz.Traditionally, consequence modelling of dense gas releases from pipelines at major hazard impact levels is performed using integral models with limited or no consideration being given to weather bias or topographical features of the surrounding terrain. Whilst dispersion modelling of CO₂ releases from pipelines using three-dimensional CFD models may provide higher levels of confidence in the predicted behaviour of the cloud, the use of such models is resource-intensive and usually impracticable. An alternative is to use more computationally efficient shallow layer or Lagrangian dispersion models that are able to account for the effects of topography whilst generating results within a reasonably short time frame.In the present work, the proposed risk assessment methodology for CO₂ pipelines is demonstrated using a shallow-layer dispersion model to generate contours from a sequence of release points along the pipeline. The simulations use realistic terrain taken from UK topographical data. Individual and societal risk levels in the vicinity of the pipeline are calculated using the Health and Safety Laboratory's risk assessment tool QuickRisk.Currently, the source term for a CO₂ release is not well understood because of its complex thermodynamic properties and its tendency to form solid particles under specific pressure and temperature conditions. This is a key knowledge gap and any subsequent dispersion modelling, particularly when including topography, may be affected by the accuracy of the source term.     

基于城市用地单元的自然灾害风险评估概念模型

为使城市土地利用规划与灾害风险管理更好地结合,从城市规划的基础单元———城市用地系统出发,提出基于城市用地单元的区域综合自然灾害风险评估的概念模型。基于城市用地单元的灾害风险评估,包括城市土地利用单元上潜在致灾因子及承灾体自然脆弱性相结合的灾损风险评估,以及人口、经济、社会因素等所引起的社会脆弱性评估2个方面。通过耦合矩阵,得到5个等级的灾害风险。其中,灾损风险与脆弱性均较高的城市用地单元或区域应得到高度关注。基于城市土地利用单元的灾害风险评估模型的应用关键,在于建立城市用地单元的数据库。提高基础数据的精度,有助于提高评估结果的精度。     

Modelling accidental releases of dangerous gases into the lower troposphere from mobile sources

The article reports the results of different methods of modelling releases and dispersion of dangerous gases or vapours in cases of major accidents from road and rail transportation in urban zones. Transport accidents of dangerous substances are increasingly frequent and can cause serious injuries in densely inhabited areas or pollution of the environment. For quantitative risk assessment and mitigation planning, consequence modelling is necessary.

The modelling of dangerous substance dispersion by standard methods does not fully represent the behaviour of toxic or flammable clouds in obstructed areas such as street canyons. Therefore the predictions from common software packages as ALOHA, EFFECTS, TerEx should be augmented with computational fluid dynamics (CFD) models or physical modelling in aerodynamic tunnels, and further studies are planned to do this.

The goal of this article is to present the results of the first approach of modelling using these standard methods and to demonstrate the importance of the next development stage in the area of transport accident modelling of releases and dispersions of dangerous substances in urban zones in cases of major accident or terrorist attacks.     

基于潜在生命损失的危险化学品仓储区规划选址和安全布局方法研究

在现有基于风险的土地使用安全规划方法的基础上,通过引入潜在生命损失这一综合风险评价指标,建立了基于移动危险源潜在生命损失的危险化学品仓储区规划选址模型和基于固定危险源潜在生命损失的仓储区安全布局优化模型。在此基础上,提出了危险化学品仓储区规划选址和安全布局优化方法,并通过案例分析验证了该方法的适用性和可行性。采用该规划选址和安全布局优化方法可提高区域土地使用安全规划的效率,为进行城市重大危险源的规划选址和安全布局提供了新的思路。     

Environmental risk mapping of accidental pollution and its zonal prevention in a city

Accidental releases of pollution can have severe environmental, societal, economic, and institutional consequences. This paper considers the use of risk mapping of accidental pollution events, and zonal prevention measures for alleviating the impact on large urban areas. An Environmental Pollution Accident Risk Mapping (EPARM) model is constructed according to a mapping index system supported by quantitative sub-models dedicated to evaluating the risk arising from different sources of potential accidental pollution. The EPARM approach consists of identifying suitable indexes, assessment of environmental risk at regional and national scales based on information on previous pollution accidents and the prevailing environmental and social conditions, and use of GIS to map the overall risk. A case study of pollution accidents in Minghang District, Shanghai, China is used to demonstrate the effectiveness of the model. The paper also proposes a systemic framework for accidental environmental pollution risk prevention, and detailed countermeasures for specific risk zones.     

A risk assessment methodology for high pressure CO2 pipelines using integral consequence modelling

This paper presents a risk assessment methodology for high pressure CO₂ pipelines developed at the Health and Safety Laboratory (HSL) as part of the EU FP7 CO2Pipehaz project. Until recently, risk assessment of dense phase and supercritical CO₂ pipelines has been problematic because of the lack of suitable source term and integral consequence models that handle the complex behaviour of CO₂ appropriately. The risk assessment presented uses Phast, a commercially available source term and dispersion model that has been recently updated to handle the effects of solid CO₂. A test case pipeline was input to Phast and dispersion footprints to different levels of harm (dangerous toxic load and probit values) were obtained for a set of pipeline specific scenarios. HSL's risk assessment tool QuickRisk was then used to calculate the individual and societal risk surrounding the pipeline. Knowledge gaps that were encountered such as: harm criteria, failure rates and release scenarios were identified and are discussed.     

Mechanism analysis and risk assessment of escalation scenario in chemical industry zones

Many major hazard installations (MHIs) are located in chemical industry zones and escalation effect may be triggered when the fire or explosion occurs on a MHI. To investigate the mechanism of the accident escalation, a systematic quantitative assessment methodology is proposed by the considering the feature and uncertainty of the escalation scenario. The main accident energy carriers of the escalation are heat radiation, overpressure of blast and fragments. The escalation probability, joint influence of the three energy carriers and risk characterization of the accident scenarios are carried out. By the new methodology, the escalation scenario in chemical industry zones can be analyzed and the risk escalation morphology is demonstrated by the simulation software. The visualized risk cloud figure gives a supplementary way to prevent the escalation scenario in chemical industry zones planning.     

Dynamic probability assessment of urban natural gas pipeline accidents considering integrated external activities

Urban gas pipelines usually have high structural vulnerability due to long service time. The locations across urban areas with high population density make the gas pipelines easily exposed to external activities. Recently, urban pipelines may also have been the target of terrorist attacks. Nevertheless, the intentional damage, i.e. terrorist attack, was seldom considered in previous risk analysis of urban gas pipelines. This work presents a dynamic risk analysis of external activities to urban gas pipelines, which integrates unintentional and intentional damage to pipelines in a unified framework. A Bayesian network mapping from the Bow-tie model is used to represent the evolution process of pipeline accidents initiating from intentional and unintentional hazards. The probabilities of basic events and safety barriers are estimated by adopting the Fuzzy set theory and hierarchical Bayesian analysis (HBA). The developed model enables assessment of the dynamic probabilities of consequences and identifies the most credible contributing factors to the risk, given observed evidence. It also captures both data and model uncertainties. Eventually, an industrial case is presented to illustrate the applicability and effectiveness of the developed methodology. It is observed that the proposed methodology helps to more accurately conduct risk assessment and management of urban natural gas pipelines.     

城市重大危险源管理中的GIS应用研究

在阐述重大危险源管理要求的基础上,研究地理信息系统在重大危险源信息描述、数据管理、风险评价和风险绘制、事故预警以及事故应急救援中的应用。通过地理信息系统描述和管理重大危险源,方便地表示和查询城市各重大危险源的地理位置;利用GIS进行风险评价和风险地图绘制,评估和表示出城市不同区域和地段的相对风险大小,便于城市发展规划;利用GIS进行事故预警,可及时发现和确定重大危险源事故隐患位置,并通过采取措施消除事故在萌芽状态;利用GIS辅助应急救援,有助于分析事故的发展趋势、影响范围和寻求事故救援的最佳路径等其他重大救援决策。