SMR型LNG装置入口节流负荷调节特性的模拟研究

Adjustment performance and components optimization for SMR LNG plant with load adjustment method of inlet throat

SMR液化工艺在小型LNG工厂中得到广泛应用,由于LNG工厂经常运行于非设计工况下,因此负荷调节方法及调节特性十分重要。文中将基于HYSYS的工艺流程模拟与离心式压缩机性能仿真相结合,建立了SMR装置的变工况数学模型及工艺模拟方法,并对采用压缩机入口节流方法调节负荷时的调节特性进行了模拟研究。结果表明,在60%～100%负荷范围内,入口节流方式进行负荷调节有很好的效率,但当负荷降至50%以下时,调节效率会下降。采用入口节流调节负荷时应协调节流压力与冷剂循环量,并优先满足压缩机高效工作的要求。文中的模拟方法及结果对LNG装置的操作运行及设计有理论上的指导意义。

SMR process has been widely applied in small - scale LNG plant. Since the LNG facility often works at the condi- tion which is different from the design condition, the method and performance of the load adjustment is very important. The mathematic model of SMR facility was established by combination of HYSYS process simulation and performance simulation of centrifugal compressor. The simulations were done to study the performance and regulation of load adjustment with inlet throat method. The results show that the adjustment performance is rather good in 60% to 100% load range. However, the efficiency is relatively low when the load is under 50%. The flowrate of mixed refrigerant should be adjusted accordingly. The control strategy is to guarantee the high efficiency of the MR compressor. The simulation method and results could be conductive for operation and design of a LNG plant.