Mechanism analysis and simulation of methyl methacrylate production coupled chemical looping gasification system

Abstract

Nowadays, the efficient and cleaner utilization of coal have attracted wide attention due to the rich coal and rare oil/gas resources structure in China. Coal chemical looping gasification (CCLG) is a promising coal utilization technology to achieve energy conservation and emission reduction targets for highly pure synthesis gas. As a downstream product of synthesis gas, methyl methacrylate (MMA), is widely used as raw material for synthesizing polymethyl methacrylate and resin products with excellent properties. So this paper proposes a novel system integrating MMA production and CCLG (CCLG-MMA) processes aiming at “energy saving and low emission”, in which the synthesis gas produced by CCLG and purified by dry methane reforming (DMR) reaction and Rectisol process reacts with ethylene for synthesizing MMA. Firstly, the reaction mechanism of CCLG is investigated by using Reactive force field (ReaxFF) MD simulation based on atomic models of char and oxygen carrier (Fe2O3) for obtaining optimum reaction temperature of fuel reactor (FR). Secondly, the steady-state simulation of CCLG-MMA system is carried out to verify the feasibility of MMA production. The amount of CO2 emitted by CCLG process and DMR reaction is 0.0028 (kg CO2)−1·(kg MMA)−1. The total energy consumption of the CCLG-MMA system is 45521 kJ·(kg MMA)−1, among which the consumption of MMA production part is 25293 kJ·(kg MMA)−1. The results show that the CCLG-MMA system meets CO2 emission standard and has lower energy consumption compared to conventional MMA production process. Finally, one control scheme is designed to verify the stability of CCLG-MMA system. The CCLG-MMA integration strategy aims to obtain highly pure MMA from multi-scale simulation perspectives, so this is an optimal design regarding all factors influencing cleaner MMA production.