Research On Environmental Risk Assessment And Emergency Capability Evaluation Methods And Spatial Decision Support Systems In Petrochemical Industrial Area

Chemical and petrochemical industry is one of the pillar industries in China's economy. Under the joined influence of land resources shortages, fast industrialization and urbanization, many chemical and petrochemical areas have gradually evolved into a hidden danger to urban areas, leading to frequent occurrences of serious safety accidents and environmental emergency incidents. Therefore, it is very essential to take comprehensive analysis on area risks, emergency capability and then take effective measures against the risks.Based on the analysis of the actual demand and status of relevant studies, this thesis carried out a study mainly involving three issues:how to comprehensively analyze the risks; how to effectively deal with the emergency; and, how to support decision marking. The detail work includes the following content:(1) A regional environmental risk assessment method based on severity and vulnerability theory was developed. According to the characteristics of multi-risk sources, multi-pathways and multi-environmental sensitive targets in chemical and petrochemical area, a new risk matrix was introduced, the regional environmental risk assessment process was constructed, the risk adjustment and land use planning framework was developed based on the severity index and vulnerability index from ARAMIS methodology. The method was applied into Dagushan Peninsula. The potential impact extent of the four hazard effects of the regional risk sources, including thermal radiation, overpressure, toxic concentration and liquid pollution, was analyzed comprehensively; the vulnerability of the three environmental sensitive targets (population target element, environmental target element, property target element) under the four hazard effects was evaluated; the case region was then separated into very high risk, high risk, middle risk and low risk areas; finally the land use planning schemes were put forward from the points of risk sources and environmental goals. The case study indicated that the method could characterize the risks in a more comprehensive perspective, which has certain advantages in solving the risk assessment and planning issues in large-scale chemical and petrochemical areas.(2) A method for environmental emergency response capacity evaluation was proposed by jointly applying the fuzzy optimization planning model and two element semantic model. Aimed at the subjective uncertainty in emergency response capability evaluation process, an evaluation index system for emergency response capacity was constructed based on the three-dimensional structure. It consisted of four criteria layers (prevention and preparation capability, monitoring and early warning capability, emergency response capability, recovery and reconstruction capability) and fifteen sub-criteria layers (risk source management, Environmental target, risk analysis, etc.). The two element semantic model and fuzzy optimization planning model were introduced to overcome the problems of the quantitative expression of language variables and the consistency check in the weight determination process of the index system. The method was applied into three chemical enterprises. Based on the index system, the emergency response capability level of each enterprise was analyzed and the related measures were put forward. This method has the ability to solve the problem of subjective uncertainty in decision-making process and can provide methodological reference for emergency response capability construction in chemical and petrochemical areas.(3) Spatial decision support system (SDSS) for environmental risk assessment and emergency response capability evaluation was developed. In order to overcome the complexity of the methods in research (1) and (2) and meet the practical management demands, based on the methods proposed in (1) and (2), a SDSS was developed for environmental risk assessment and emergency capability evaluation by adopting C/S as the main structure and applying the techniques of ArcGIS Engine,.NET, Oracle, etc. The system supplied four functions:(?) environmental risk source management and severity analysis; (?) Environment sensitive target management and vulnerability analysis; (?) emergency management and emergency response capability evaluation; and, (?) regional environmental risk assessment and decision support. It is beneficial to improve the decision support capability and information level for risk management.In sum, this thesis can be considered as a useful exploration for the related methods of environmental accident prevention and emergency. The research methods applied include risk assessment method, emergency response capability evaluation method and decision support system, etc. The research tools involve accident consequence simulation, GIS modeling, fuzzy math, information and decision support system development, etc. It is promising for providing methodological reference and support tools for environmental risk management in chemical and petrochemical industries.