含硫化氢天然气泄漏事故的硫化氢中毒灾害分析

A new method for analyzing the hazardous hydrogen sulfide poisoning caused by the sulfurous natural gas leakage

应用前文建立的天然气长输管道泄漏扩散模型,在大量事故统计分析基础上,针对含硫化氢天然气泄漏后硫化氢导致的化学灾害后果提出了一种新的风险分析方法。综合考虑概率风险评价法和伤害范围评价法的特点,研究了不同规模泄漏事故可能导致的个人风险和社会风险,并绘制了相应的社会风险曲线图。

The present paper is aimed to introduce a new method for analyzing the hydrogen sulfide poisoning hazards caused by the sulfurous natural gas leakage.As is well known,China is rich in sulfurous natural gas,whose deposits are huge and widely distributed in our country.However,due to its toxic nature,the release of hydrogen sulfide-containing natural gas from the pipeline tends to bring about serious threats to human life and material property near its leakage source.To predict or evaluate the threat of hydrogen sulfide poisoning,a lot of measures can be taken to test or evaluate such hydrogen sulfide poisoning source,and QRA（Quantitative Hazard Analysis） method can be thought of as an effective one.But,the above said analysis method doesn＇t seem enough for the sake of security management of its exploration,letting alone to do the quantitative hazards,such as individual intake hazard and societal hazard, for example,the community poisoning threat.It is for this need that we would like to propose a new analysis method for hydrogen sulfide poisoning of hydrogen sulfide-bearing natural gas known as the comprehensive hazards analysis method, based on the study of the historical accident-statistical data of EGIG（European Gas Pipeline Incident Data Group） and BG Transco,while the probability of hazard and the scope of the damage were taken into account.While working at our method,we have also analyzed the three leakage scenarios of the East-Sichuan Gas Transportation Project,including the individual hazard analysis and societal hazard analysis.In addition,we have adopted the Gaussian plume model to calculate the dispersion region of the well blown-out of natural gas containing sulfide hydrogen.On the basis of animal experiments,we have discovered that the hazards due to the exposure to a toxic gas depends on the two essential parameters,the toxic concentration and the exposure time,and at the same time,we have also introduced the idea of the dose-load into our hazard analysis.In so doing,we have obtained the corresponding social hazard curves and classified the hazardous areas at different leakage spots.Since the societal hazard varies significantly with such factors,as the population density,probability of fatality and so on,we have concluded that the individual hazard and societal hazard of the leakage scenarios are found all unacceptable.Thus,the proposed method can provide believable supports for the safety management and maintenance of natural gas pipeline as well as the evacuation in the accidents.