液化天然气气化站中BOG压缩机运行的动态模拟与优化

Dynamic simulation and operation optimization of BOG compressors in LNG gasification plant

关键词:  动态模拟  优化  运行  BOG  Aspen Dynamics

Key words:  dynamic simulation  optimization  operation  BOG  Aspen Dynamics

摘要:

基于LNG储罐动态模拟提出了一个BOG压缩过程的优化运行方案的算法。该算法采用了经验蒸发率模型来预测BOG(蒸发气)的产量,用MILP公式来分配BOG压缩机的负荷。最后,运用一个动态模拟软件进行安全分析。为提高精度,运用含有PR状态方程的Aspen Dy-namics软件代替了以往应用的简化动态模型。通过对LNG储罐压力的动态模拟,得到当BOG压缩机正常运行时,在安全压力范围内的波动值。该算法优于一般流程中运用的算法,并且更加安全和节能。

Abstract:

An algorithm was proposed to optimize the operation of BOG compression based on dynamic simulation of LNG tank.It adopted empirical boil off rate model to predict the BOG production,used MILP formula to distribute the BOG compressor load,and made safety analysis by using dynamic simulation software.Aspen Dynamics software with PR state equation was also adopted insteading of simplified dynamic model to improve the accuracy.By the dynamic simulation of LNG tank pressure,the undulating quantities within safe pressure ranges when the BOG compressors were operated normally have been achieved.This algorithm is better than the algorithm used in routine processes,and is safer and more energy-efficient.