高含硫气田开发安全防护距离探讨

在高含硫气田作业场所设置安全防护距离,可以在发生井喷、含硫天然气泄漏事故时减少火灾、爆炸、H2S中毒等造成的人员伤亡,是控制和降低安全风险的有效手段之一。为此,分析了国内外相关安全标准对含硫气田安全防护距离的要求,并以四川盆地某高含硫气田为例,应用国内外相关标准或方法计算井场、集气管道及净化厂的安全防护距离,开展对比分析。结果表明,依据不同的方法确定的安全防护距离偏差较大,因此建议采用定量风险评价的方法作为确定搬迁距离的依据,采用EUB推荐的查图法及公式快速确定或依据计算的150 mg/m~3 H_2S包络线范围确定应急撤离距离。针对高含硫气田开发,建议采用以下措施降低风险:(1)设置紧急截断系统,减少含硫天然气潜在泄漏量;(2)提升装置本质安全,减少事故发生概率;(3)提高应急保障水平,减轻事故影响。

Safety protection distance in high-sulfur gas field development

The safety protection distance set around high-sulfur gas field facilities is one of the effective means to control and reduce risks such as fire, explosion, H2S poisoning, etc., which may cause loss of life and personal injury. In view of this, Comparative analysis was conducted of the safety protection distances in high-sulfur gas fields regulated in the relevant safety standards and codes between China and other countries. In a case study of a high-sulfur gas field in the Sichuan Basin, the safety protection distances in the well sites, gas gathering lines and stations, and purification plants, etc. were calculated and compared by different codes and methods at home and abroad. Due to the great differences from the results, quantitative risk evaluation should be taken as the proof for determining the moving distance. Then the method and formula provided by Alberta Energy and Utilities Board (AEUB) was used to obtain the emergency evacuation distance away from the enveloped scope where the air contains 150 mg/m³ H₂S. In the end, the following proposals for sour gas field development were put forward: establishing emergency shutdown systems to reduce potential sour gas leakage rate; improving the intrinsic safety of facilities to reduce the accident probability; and promoting the emergency support capability to mitigate the impacts caused by accidents.