Thermodynamic analyses for recovering residual heat of high-temperature basic oxygen gas (BOG) by the methane reforming with carbon dioxide reaction

Abstract

For the recovery and utilization of high-temperature basic oxygen gas (BOG) generated in the basic oxygen furnace (BOF) process within iron and steel production, a thermochemical recovering method of tubular plug flow reaction is proposed. Accounting for efficient utilization of residual heat and capture of carbon dioxide, methane reforming with carbon dioxide reaction is introduced. With a linear-temperature heat source, the reacting rate, temperature and pressure distributions of mixed gas along the tubular reactor are obtained based on a thermodynamic model. The influences of three inlet parameters of temperature, total pressure, molar flow rate of methane, and a structure parameter of catalyst porosity are analyzed. The results show that with the given conditions, the reacting rate firstly increases to the maximum and then decreases gradually nearly to zero, and the reforming reaction mainly occurs at the first half of the tube. The temperature increases with the flow along the tube, but the temperature gradient decreases on the contrary. The total pressure decreases and the pressure gradient gradually increases to a certain value at the end. Both of the inlet temperature and molar flow rate of methane have big influences on the reacting rate.