由于LNG调峰气化设施的生产负荷以及LNG物性随季节或每日时段变化大,导致极端工况下浸没式燃烧气化器不能完全气化LNG,严重影响气化设施安全运行。以某调峰气化设施工厂为例,利用传热学理论,分别计算出某年冬季该厂浸没式燃烧气化器在设计工况和极端工况下的总传热系数。计算结果表明，极端工况下浸没式燃烧气化器不能为换热管内的LNG提供足够热量,少量LNG不能气化,引起管道低温脆裂,导致爆炸事故。为解决极端工况下浸没式燃烧气化器不能完全气化LNG的问题,在不过度增加浸没式燃烧气化器换热面积前提下,在调峰气化设施界区设置压力调节阀,分别计算出浸没式燃烧气化器在设计工况和实际工况下的总传热系数,保证浸没式燃烧气化器能够提供完全气化LNG的热量,确保操作压力低限值,提高调峰气化设施的安全性。调峰气化设施界区设置压力调节阀的方法可为类似气化设施设计提供借鉴。

As the production load of LNG vaporization facilities for peak-shaving station and the physical properties of LNG vary greatly with the season or time of day,the LNG could not be vaporized completely bysubmerged vaporizerunder extreme operating conditions, which affected safety of the vaporization facility.Taking avaporizationfacility for peak-shaving as an example, with the heat transfer theory, the total heat transfer coefficients of the submerged combustion vaporizer of the project under the design and extreme conditions of a certain winter were calculated respectively.The results showed that when the vaporizer was operating under extreme working conditions, the vaporizer could not provide sufficient heat to the LNG in the heat exchange tube.As a result, a small amount of LNG could not be vaporized, finally resulting in low-temperature embrittleness of the pipeline and an explosion.Tosolve the above issue, with properly increased heat exchange area of submerged vaporizer,apressure regulating valve was set up at the boundary of the peak-shaving facility to calculate the total heat transfer coefficient of the submerged combustion vaporizer under the design andactualconditions.Sufficient heat from thesubmerged vaporizercan be guaranteed to provide for the complete vaporization of LNGand the operating pressure is ensured to have a lower limit valueso as to improve the safety of vaporization facilities for peak shaving.This method can provide reference for the design of similar vaporization facilities.