Optimal integration design of sustainable ethylene glycol production process considering economic benefit and environmental impact

Abstract

The requirement for ethylene glycol (EG) continues to surge owing to the booming demand for indispensable platform materials. Unfortunately, there is limited insight into engineering modeling, process enhancement, and process optimization to achieve carbon neutrality in ethylene glycol production. Herein, four biomass-to-ethylene glycol (BtEG) processes that integrate renewable energy for hydrogen production and CO2 utilization are proposed to find the best strategy for the carbon-neutral and cost-effective development of the ethylene glycol industry. Rigorous steady-state modeling and simulation of the proposed BtEG processes with various gasification agents are conducted to investigate the effect of different gasification agents on the performance of the BtEG processes. The technoeconomic and environmental performance of the proposed processes is assessed and compared with the conventional process. Results show that the proposed BtEG processes can significantly boost the system performance of the conventional process. The carbon utilization efficiency, exergy efficiency, and internal rate of return of four proposed BtEG processes are improved by 38.96%–43.2%, 0.98%–7.13%, and 1.94%–11.28%, respectively. The environmental performance of the proposed BtEG processes is greatly superior to that of the conventional process since the life cycle GHG emissions of the proposed processes are negative, which are lower than −1.47 t/t. Therefore, this study provides a sustainable and cost-efficient improvement direction for the carbon-intensive ethylene glycol industries.