CNG加气站设备安全风险评价的关键问题

随着城市加气站的蓬勃发展和国家大力提倡的城际间加气站网络建设逐步展开，CNG汽车加气站及设备保有量与日俱增，加气站设备安全风险评价十分必要和迫切。提出了加气站设备选型及安全风险评价必须遵循“安全第一，性能第二，成本第三”的基本原则，对其安全风险评价中的关键问题进行了深入研究：①加气站安全事故的表现形式及爆炸危险区域划分；②安全风险评价应考虑的关键系统及关键部件；③安全风险评价易忽略的危险因素--主要易损件的安全可靠性及使用寿命、气质问题、在线检测系统及报警系统、辅助电加热（保温）、降温及强制通风设备、含油率问题。明确了加气站安全风险评价应从站内扩展到站外，并对储气型式的安全风险评价提出了新的判断标准。据此为政府部门加强安全监管、加气站业主加强安全自评提出了切实有效的操作性建议。

MAIN ISSUES IN SAFETY RISK ASSESSMENT ON THE EQUIPMENTS AT CNG FILLING STATIONS

With the vigorously developed urban CNG filling stations and progressively started networks of inter-city CNG filling stations encouraged by the government,the number of CNG filling stations and equipments are increasing.This makes the safety risk assessment on the equipments of the CNG filling station necessary and urgent.After the evaluation system and criteria was set up in the previous paper,this paper proposed a fundamental principal of 'safety first,performance second,third the cost' that should be followed in the equipment selection and safety risk assessment of the CNG filling station.An intensive study was made into the main issues in safety risk assessment on equipments in CNG filling stations from the following points:a.the manifestation of accidents presented at the filling station and the obvious security line marked in the explosive(dangerous) region;b.the key system and key component to be taken into consideration;c.some easily-ignored hazard factors such as the safety reliability and service life of the main vulnerable,the quality of the gas,the online detection system and warning system,the auxiliary electric heating and heat preservation system,the cooling and mandatory ventilation equipment,the problem of oil length,and so on.In addition to ascertain that this safety risk assessment should be expanded from inside to outside of the CNG filling station,this paper put forward a new criteria for the safety risk assessment on the storage-type of CNG filling stations.Some practical proposals were suggested for the government to reinforce safety supervision and the owners of CNG filling stations to their self-judgement on security as well.