Utilizing CO₂ from refinery for methanol and electricity coproduction: System assessment

¹ Research Institute of Safety & Environment Technology, China National Petroleum Corporation, Beijing 102206, China
² Daqing Oilfield water supply Company, Daqing 163000, China
³ Chinese Academy of Environmental Planning, Beijing 100012, China

^* Corresponding author: ma-qian@cnpc.com.cn

Abstract

As one of the major energy-consuming and high-emission industries, the refineries account for 10% of global industrial carbon emissions, of which about 25% is emitted by fluid catalytic cracking (FCC) process. Therefore, CO₂ capture from FCC flue gas create the possibility for low-carbon refineries. We developed a novel CO₂ utilization process to methanol production modeling using Aspen Plus. Meanwhile, organic Rankine Cycle (ORC) power generation technology was coupled to recover the waste heat of the system. A five-million-ton FCC unit in China was selected as a case study. We conducted some analysis for the process, the results show that the developed system boosts the energy efficiency of the FCC unit by 2.8%. The annual capacity of the waste heat power generation unit is 4.8 GWh, with a thermal efficiency of 5.9%.