制氢装置中变气换热网络分析

Analysis of Problems in the Heat Transfer Network of Shift Gas in Hydrogen Generation Plant

分析了改造前后制氢装置中变气换热流程运行过程中出现的问题,包括阀门冲刷腐蚀、除氧器除盐水上水温度波动大和除氧器压力波动大等,并运用Aspen软件对中变气换热流程进行了模拟分析。结果表明:中变气通过换热回收的能量较少是导致改造前后空冷入口温度均较高的主要原因。提出了3种改造方案,经过分析比较,利用旧除氧用蒸汽发生器用以产生外供0.4 MPa蒸汽的方案,在综合装置能耗、流程改动、投资及改造耗时等各个方面最优。制氢中变气换热流程进一步的工艺优化方向是使用自产的0.4 MPa蒸汽代替1.0 MPa蒸汽供制氢除氧器和酸性水汽提塔使用。

The problems in the running of heat transfer flow of shift gas in hydrogen generation plant before and after reengineering were analyzed in details,including serious valve erosion-corrosion,the fluctuated temperature of desalted water,the unstable pressure of deaerator,etc. The software Aspen were applied in the analysis of the heat transfer flow of shift gas. The result suggested that only a small portion of shift gas heat was recovered by means of heat exchange,which was the main cause leading to the high temperature of air-cooler inlet. Three reconstructing schemes were provided,analysis and comparison were made and it come to the conclusion that reusing of the exiting deaerator E-106 to generate 0. 4 MPa steam was the relative optimum considering overall plant energy consumption,process reconstruction,investment and time cost. Referring to the further process optimization,0. 4 MPa steam produced in the plant could be used as an alternative for 1. 0 MPa steam.