Numerical Simulation and Process Optimization of H2 Production from Dimethyl Ether Steam Reforming

Abstract

A numerical study was conducted to optimize the process of hydrogen production from dimethyl ether (DME) steam reforming. The reforming system was composed of a DME steam reforming reactor, a high-temperature water–gas shift reactor, a low-temperature water–gas shift reactor, and a preferential oxidation reactor. The mathematical model of the DME steam reforming reactor was set up and validated by a self-designed experimental equipment. Based on the model of the reforming reactor, a process optimization model accomplished by waste heat recovery was established by using commercial software. By using the model, the effects of various parameters on system thermal efficiency and the hydrogen flow rate were analyzed. The hydrogen flow rate and the system thermal efficiency increased with the increase of steam∶DME ratio and the temperature of the steam reforming reactor. The hydrogen flow rate and the thermal efficiency changed little with the increase of temperature of the high-temperature water–gas shift reactor and low-temperature water–gas shift reactor. The system thermal efficiency decreased and the hydrogen flow rate increased with the increase of the DME inlet flow rate. The results will provide useful data to design and operate a H2 production system.