天然气气封系统在原油储罐呼吸中的应用

Application of natural gas sealing system in crude oil storage tank breathing

通过分析原油储罐在运行过程中出现大小呼吸的原因及原油储罐罐顶安装呼吸阀解决大小呼吸时存在的安全隐患及大气污染等缺点,提出了利用天然气气封系统解决上述问题的方法。当储罐气体压力高于气封压力时,储罐内气体通过泄压阀自动排入火炬水封罐内;当储罐内气体冷凝或收缩导致储罐内压力下降并低于系统设定值时,通过补气系统中的旋风分离器分离出的天然气对储罐进行补气封,以阻止外界气体进入。该系统已在中石化加蓬AKONDO油田储罐中成功应用,有效解决了传统罐顶安装呼吸阀导致的排气对周围空气的污染和吸气造成罐内空气和油蒸气混合的情况,避免了储罐的胀罐和瘪罐的发生,为储罐吸气、排气现象引起的安全和环保问题提供了一种新的解决思路。

Based on the investigation on reasons causing working loss and standard storage loss in crude oil tanks and the analysis on shortcomings causing potential hazards or air pollution in the resolution of installing breathing valves at the roof of crude oil tanks, we put forward an approach of using natural gas sealing system to solve the aforesaid problems. When gas pressure in the crude oil tank is higher than that of the natural gas seal, gas wilt freely flow into water sealed tank of flare system through pressure relief valve. In the event of gas condensation or contraction in the crude oil tank which causing gas pressure dropping below the set value, natural gas cyclone separator will supplement gas into crude oil tank to prevent gas to flow in from outside. The natural gas sealing system has been applied in storage tanks in Sinopec Gabon AKONDO Oil- field, and has effectively solved the problem of exhaust gas pollution caused by traditional method of installation breathing valves at crude oil tank roof and the mixture problem of air and oil gas caused by crude oil tank suction. The natural gas sealing system has also been proven effective in avoiding crude oil tank sunken or expanded. It provides a new solution for issues in terms of storage tank safety and environmental problems caused by the gas suction and exhaust of crude oil tank.