大型LNG储罐预冷过程影响因素分析

Analysis of Influencing Factors on Precooling Process of Large LNG Storage Tank

大型LNG储罐是LNG生产企业和LNG接收站中最为关键的储存设施之一,其整体投资相对较高。由于LNG温度超低,当大量的LNG进入到常温储罐后会导致其内部出现的非均匀性温度骤降,不仅会导致储罐内部的压力迅速升高,同时也会导致罐体出现明显的应力集中现象,从而对储罐的安全性产生巨大威胁。因此在正式通入LNG前需要对大型LNG储罐进行预冷,即通过预冷将储罐由常温状态缓慢且均匀的降低至低温状态,以避免储罐内部温度骤降而产生的不利影响。由于预冷属于高风险且具有较高技术水平的工作,因此需对预冷过程中的各类影响因素进行充分的分析,以确保预冷工作的顺利进行。

Large LNG storage tank is one of the most critical storage facilities in LNG production enterprises and LNG terminals, and its overall investment is relatively high. Due to the extremely low temperature of LNG, when a large amount of LNG enters the normal temperature storage tank, it will cause a sudden drop in its internal non-uniform temperature, which will not only lead to a rapid increase in the pressure inside the storage tank, but also lead to obvious stress concentration in the tank body, thus posing a huge threat to the safety of the storage tank. Therefore,large LNG tanks need to be precooled before LNG is officially introduced, that is, the tanks are slowly and evenly reduced from normal temperature to low temperature through precooling, so as to avoid adverse effects caused by sudden drop of internal temperature of the tanks. As precooling is a high-risk and highly technical work, it is necessary to fully analyze various influencing factors in the precooling process to ensure the smooth progress of precooling.