全容式LNG储罐绝热性能及保冷系统研究

我国大型LNG接收站中的储罐均为全容式LNG储罐，其通常处于低温微正压状态，外界热量的漏入会引起LNG的蒸发，增加能耗，也可能会使储罐产生分层及翻滚现象，对其安全造成较大威胁，因此，需要对它的绝热性能及保冷系统进行研究。为此，根据全容式LNG储罐的结构特点，分别对罐顶、罐壁和罐底进行了漏热量计算，结合实例进行了LNG储罐总漏热量及日蒸发率的计算分析，探讨了LNG储罐的绝热性能，找到了影响储罐漏热量的主要因素：保冷材料的导热系数、保冷层的厚度、储罐表面的吸收率、环境温度等，为LNG储罐保冷系统的设计提供了相关依据；并根据LNG储罐保冷系统的需要，归纳总结了保冷材料的选择原则、施工方法及其注意事项。

Thermal insulation performance and cold insulation system of full containment LNG storage tanks

The storage tanks at China's large LNG receiving terminals are all full containment LNG tanks. Generally, these tanks are in the state of low temperature and micro positive pressure. When external heat is absorbed, LNG will evaporate and energy consumption will be increased. In addition, it might result in stratification and rollover of the tanks, causing potential safety hazards. Therefore, it is necessary to perform researches into the thermal and cold insulation performance of LNG storage tanks. Based on the structural characteristics of full containment LNG tanks, calculations are conducted of the heat leakage of tank roof, wall and bottom. This paper further takes examples to calculate and analyze the total heat leakage and daily evaporation rate of the tanks, and discusses the coal insulation performances of LNG storage tanks and the main influencing factors of the heat transfer. The paper provides reference to the design of the cold insulation system of LNG storage tanks. In addition, it also performs a study on the selection principles of insulation materials, construction methods and points for attention of the cold insulation system of LNG storage tanks.