摘要
新建LNG接收站通过首船进行第一座储罐预冷时,储罐预冷后期往往出现温降困难的实际情况。针对该问题,开展理论分析及ASPEN HYSYS软件模拟计算,得出因卸料总管温升导致可用的LNG量不足是储罐预冷后期温降困难的主要原因。结合国内多座LNG储罐预冷经验,从设计优化和调试两个角度提出了解决上述问题的推荐方案:在进行预冷管线、预冷调节阀、预冷喷嘴等设计选型时,应在理论储罐预冷最大用量的基础上适当考虑一定余量,兼顾到由于上述原因造成的LNG损失流量;调试时可以通过缓慢有规律地打开顶部进料阀的旁通阀来增大LNG流量,使储罐预冷后期的温降速率控制在3~5℃/h的合理范围。该研究结果可为同类LNG储罐设计和预冷操作提供参考。
It is difficult to lower the temperature of LNG storage tank in the later stage of pre-cooling when a new LNG terminal carries out the pre-cooling for the first storage tank through the first ship.The reasons for the above phenomenon are discovered through theoretical analysis and ASPEN HYSYS simulation calculation,which show that the shortage of available LNG due to temperature rise of unloading pipeline is the main reason for the difficulty in temperature drop of storage tank in the late stage of pre-cooling.Based on the experience in pre-cooling of several domestic LNG storage tanks,the recommended solutions to the above issues are proposed from the perspectives of design optimization and commissioning.In terms of design optimisation,consider the provision of suitable design margin over and above the theoretical maximum amount of pre-cooling of storage tank when designing and selecting pre-cooling pipelines,pre-cooling regulating valves and pre-cooling nozzles,while taking into account the flow loss of LNG caused by the above reason.In terms of commissioning,the by-pass valve of overhead charging valve can be opened slowly and regularly to increase LNG flow,so as to keep the rate of temperature drop of LNG storage tank between the optimum range of 3~5℃/h in the later stage of pre-cooling.The research results can provide reference for the design and pre-cooling of LNG storage tanks of the same nature.
作者
张强强
李连强
贾砼
王乃民
张宝和
Zhang Qiangqiang;Li Lianqiang;Jia Tong;Wang Naimin;Zhang Baohe(Offshore Oil Engineering Co.,Ltd.,Tianjin,300461,China)
出处
《天然气与石油》
2020年第5期25-30,共6页
Natural Gas and Oil
关键词
LNG接收站
LNG储罐
预冷
温降困难
调试
LNG terminal
LNG storage tank
Pre-cooling
Difficulty in temperature drop
Commissioning
