Thermodynamic and techno-economic analyses of a novel integrated process of coal gasification and methane tri-reforming to ethylene glycol with low carbon emission and high efficiency

Abstract

Coal to ethylene glycol technology has been fruitfully developed due to the abundant reserve of coal and the low production cost. However, its sustainable development is plagued by the high CO2 emissions. Hence, a novel coal to ethylene glycol process integrated with methane tri-reforming technology is proposed, simulated, and optimized for low carbon emission and high efficiency. The effects of the key operational parameters on the performance of the proposed process are analyzed and optimized along with the established rigorous system modeling and simulation models. Results show the optimal ratio of coke oven gas and coal of the proposed process is 95 kmol/t, the optimal ratio among CH4, CO2, H2O and O2 of the tri-reforming unit is 1: 1.43: 2.15: 0.44, and its optimal temperature is 850 °C. Compared with the conventional process, the carbon and exergy efficiencies of the proposed process are increased by 50.94% and 15.16%, the capital investment and production costs are saved by 16.1% and 14.3%, and the direct CO2 emission is reduced by 98.06%. Therefore, it is a promising method for coal based chemical processes to integrate methane tri-reforming technology to save energy and reduce carbon emissions.