天然气制氢尾气碳减排工艺设计与优化

开发多种类分离膜与压缩冷凝耦合的梯度回收工艺,实现H₂和CO₂等组分高价值利用。考察压力、产品浓度和不同氢膜单元对工艺的影响。通过Aspen HYSYS对10000 Nm³/h处理量的工艺优化模拟得出：采用单级氢膜单元和一级二段氢膜单元,尾气进膜压力2700 kPa和H₂产品浓度60%时,工艺经济性最佳,分别实现H₂回收率81%和90%、CO₂回收率58%和60%、燃气热值16.7 MJ/Nm³和18.2 MJ/Nm³、投资回收期26.1 个月和24.4 个月。采用二级氢膜单元投资最少,最佳投资回收期16.5 个月时,氢气产品纯度为52%,低于制氢吸附装置设计要求。

DESIGN AND OPTIMIZATION OF CARBON EMMISLON REDUCTION PROCESS OF VENT GAS HYDROGEN PRODUCTION FROM NATURAL GAS

In this regard, a gradient recovery process coupled with various types of separation membranes and compression condensation is developed to achieve high-value utilization of components such as H₂ and CO₂. The effects of pressure, product concentration and different hydrogen membrane units on the process are investigated. Through the process optimization simulation of Aspen HYSYS for a throughput of 10000 Nm³/h, it is concluded that when the single-stage hydrogen membrane unit and the single-stage two-step hydrogen membrane unit are used, the process economy is best when the exhaust gas inlet pressure is 2700 kPa and the H₂ product concentration is 60%. The H₂ recovery rate is 81% and 90%, the CO₂ recovery rate is 58% and 60%, the gas calorific value is 16.7 MJ/Nm³ and 18.2 MJ/Nm³, and the investment recovery period is 26.1 months and 24.4 months, respectively. When the second-stage hydrogen membrane unit is used, the investment is least, and when the best payback period is 16.5 months, the purity of the hydrogen product is 52%, which is lower than the design requirements of the hydrogen production adsorption device.