褐煤提质联产油工艺的数值模拟与火用分析

Numerical simulation and exergy analysis of liquid from coal process

关键词:  LFC工艺  热解提质  数值模拟  火用分析

Key words:  LFC process  pyrolysis  numerical simulation  exergy analysis

摘要:

通过褐煤提质联产油工艺(LFC)实验装置进行芒来褐煤热解提质实验,取得流程模拟中需要的原始数据,在对LFC工艺流程模拟的基础上,对其进行火用分析,计算各操作单元的火用损失,分析火用损失产生的原因,指出提高火用效率的方法。结果表明:原煤处理量为1000.00 kg/h时,须补充甲烷37.80 kg/h;火用损失的主要原因是由于热量传递的不可逆性和化学反应的不可逆性;LFC工艺的火用效率为74.39％,可以通过改进工艺、回收利用半焦和热解气的物理火用来提高系统的火用效率。

Abstract:

Liquid from coal (LFC) is a pyrolysis technology for upgrading lignite. To obtain data required in the simulation, related experiments were performed by using LFC experimental device. Then LFC process was simulated in Aspen Plus. Based on thermodynamic data obtained from the simulation, exergy was determined for process streams. Exergy destruction and exergy efficiency were calculated. The results show that when the handling capacity of raw coal is 1000.00 kg/h, required methane is 37.80 kg/h. The main reason for the loss of exergy is the irreversibility of heat transfer and the irreversibility of chemical reaction. Overall exergy efficiency of LFC process is 74.39％. It can be increased by recycling physical exergy of semicoke and pyrolysis gas to improve verall exergy efficiency.