基于LNG冷能发电的朗肯循环关键参数分析优化

Analysis and Optimization of Key Parameters of Rankine Cycle Based on LNG Cold Energy Power Generation

经过对传统两级低温朗肯循环进行模拟分析,为了提高系统的净输出功,提出了改进的两级低温朗肯循环系统。在系统初始参数与循环工质不变的情况下,以改进的两级低温朗肯循环的净输出功为研究对象。利用HYSYS过程模拟软件对其进行了逐级分析优化,得到优化后系统的关键参数为:系统低、高温级循环中工质的蒸发压力分别为4.2、0.64 MPa,冷凝压力均为0.1 MPa,LNG的气化压力为1.2 MPa,此时系统的净输出功最大。

After simulating and analyzing the traditional two-stage low-temperature Rankine cycle,an improved two-stage low-temperature Rankine cycle system is proposed in order to improve the net output work of the system.The net output work of the improved two-stage low temperature Rankine cycle is studied under the condition that the initial parameters of the system and the working fluid of the cycle are unchanged.HYSYS was used to analyze and optimize it step by step,and the key parameters of the optimized system were obtained as follows:the evaporation pressure of the working substance in the low and high temperature cycles of the system was 4.2 MPa and 0.64 MPa respectively,the condensation pressure was 0.1 MPa,and the gasification pressure of LNG was 1.2 MPa,at which time the net output work of the system was the largest.