Comparative study of coal, natural gas, and coke-oven gas based methanol to olefins processes in China

• Get advantages and challenges of olefins production from alternative fossil resource.
• Propose co-feed systems of coal with natural gas or coke-oven gas to olefins.
• Achieve decrease in CO2 emissions and increase in efficiency of coal-to-olefins.

Traditional olefins production mainly depends on oil. In view of the short supply of oil, feedstocks are expanded to coal, natural gas, coke-oven gas, and methanol in China. In this paper, a comparative study of alternative olefins production is conducted from aspects of techno-economic feasibility and environmental friendliness. Results show that coal-to-olefins has a significant cost advantage. However, it suffers from low energy efficiency and serious CO2 emissions. To address these problems, this study proposes and analyses coal-to-olefins with CO2 capture, coal and natural gas-to-olefins, and coal and coke-oven gas-to-olefins. The two co-feed systems ensure great reduction of CO2 emissions and significant improving energy efficiency. They should be actively developed in regions with rich coal and gas. While in regions with rich coal and lean gas, coal-to-olefins with CO2 capture should be developed in large scale. This paper also provides several suggestions on planning these olefins production routes in China.