基于H_2S毒性负荷的山区含硫气井应急计划区的划分方法

Approach to evaluate emergency planning zones for the sour gas wells in the mountain areas of China based on H_2S toxic load

研究山区含硫气井应急计划区划分方法,为制订其安全生产标准提供科学依据。选择典型山区地形的3口含硫气井,采用大涡模拟方法,模拟了不同H2S释放速率、不同风速和风向、不同井喷点火时间的组合条件下H2S在大气中的扩散浓度场。用积分方法计算了各井H2S毒性负荷的时空分布,研究了H2S毒性负荷与H2S释放速率之间的关系,建立了以H2S释放速率为指标的山区含硫气井应急计划区的划分方法。结果表明,本次分析所用的591口H2S释放速率大于零的川渝地区含硫气井中,16.75%的含硫气井应急计划区半径大于公众安全防护距离。对于中国主要含硫气井集中分布在人口密集的川渝地区的实际情况而言,该方法是比较适用且可行的。

The approach to evaluate emergency planning zones for the sour gas wells in the mountain areas of China is established to offer scientific basis for planning industry safety standard.The concentration fields of H2S dispersion in three sour gas wells at the typical mountain terrain were simulated by the large eddy simulation method under the conditions of different H2S release rates,ignition time for the wells out of control,various wind directions and wind speed.Furthermore,the temporal and spatial distributions of H2S toxic load were calculated with the integral calculation method.The relationships between H2S toxic load and H2S release rates of the sour gas wells were discussed.The method for determining emergency planning zone of sour gas wells in the mountain areas was presented,taking H2S release rate as an indicator.The results show that the emergency planning zones of 16.75 percent of 591 sour gas wells in Sichuan and Chongqing area are greater than the public safety protection distance in this research.This approach is more applicable and feasible for the most of sour gas wells in Sichuan and Chongqing area.