硫化氢泄漏后果定量分析方法及指标响应规律

为了定量分析不同场景下H2S泄漏影响范围及各参数的响应规律，为H2S的泄漏防护提供定量数据，根据统一扩散模型和重气扩散理论，应用挪威船级社的 PHAST软件研究了H2S在不同泄漏条件下的扩散特征、浓度分布及顺风距离等. 结果表明，泄漏1 min时，中孔、大孔泄漏和破裂时的立即威胁生命和健康(IDLH)浓度顺风距离从661 m增至2404 m，IDLH浓度和最高容许浓度(MAC)的顺风距离、最大云团宽度均增大了3~4倍，持续5和30 min时变化类似；相同泄漏孔径时，中孔、大孔泄漏和破裂时，IDLH顺风距离分别缩短了31.4%, 23.8%和24.7%，最大云团宽度增加了1.4~1.7倍；风速4 m/s时，大气稳定度E的IDLH和MAC顺风距离分别是大气稳定度B的2.8倍和3.8倍；大气稳定度D、风速8.5 m/s时的IDLH和MAC顺风距离分别是风速1.5 m/s时的49.2%和39.3%；顺风距离及最大云团宽度随地面粗糙度增大呈对数降低；H2S泄漏后可能造成的主要危害是中毒，其次是喷射火、闪火及爆炸. 在进行泄漏防护时可参考定量分析结果，从个体防护和安全隔离两方面考虑；泄漏影响范围可作为H2S安全隔离的边界.

Quantitative analysis method and index response law of hydrogen sulfide leakage

It is to quantitatively analyze the influence range of hydrogen sulfide leakage under different scenarios and the response law of various parameters, and then provide quantitative data for hydrogen sulfide leakage protection. According to the unified diffusion model and the heavy gas diffusion theory, the diffusion characteristics, concentration distribution and downwind distance of hydrogen sulfide under different leakage conditions were studied by means of Process Hazard Analysis Software Tool (PHAST) of DET NORSKE VERITAS (DNV). The results showed that the immediately dangerous to life or health (IDLH) concentration downwind distance from the 661 m to the 2404 m increased when the leakage persisted for 1 min. The downwind distance and maximum cloud width of IDLH and maximum allowable concentration (MAC) have increased by 3~4 times. Changes in durations of 5 and 30 min were similar. At the same leakage aperture, the IDLH downwind distance was shortened by 31.4%, 23.8%, and 24.7%, respectively, when the mesopore and large holes leaked and ruptured. Correspondingly, the maximum cloud width has increased by 1.4~1.7 times. At a wind speed of 4 m/s, the IDLH and MAC downwind distance of the atmospheric stability E were 2.8 and 3.8 times than that of B, respectively. The IDLH and MAC downwind distances for medium stability D and wind speed 8.5 m/s were 49.2% and 39.3%, respectively, in comparison with that at a wind speed of 1.5 m/s. The downwind distance and the maximum cloud group width showed a logarithmic relationship as the surface roughness increased. The main hazardz that can be caused by hydrogen sulfide leakage were poisoning, followed by jet fire, flash fire and explosion. Quantitative analysis results can be used in leakage protection, considering both individual protection and safety isolation. The influence area of leakage can be used as the boundary of hydrogen sulfide safety isolation.