Dynamic material flow analysis of Chinese ethylene production processes and optimal pathway exploration with potential environmental-economic impacts

Abstract

China is expected to become the largest ethylene producer globally; environmental problems related with traditional ethylene production process of Chinese petrochemical industry will be further stern. This study aims to propose a feasible and optimal ethylene production expansion pathway to improve the trade-off between the environment and economy. A novel approach was adopted with material-energy-value flow analysis integration by combining dynamic scenario analysis. According to the results of scenario analysis, cleaner and lightweight production processes optimization achieved by adopting the alternative ethylene production process mix alleviated environmental pressure and achieved a weak decoupling of the low-carbon economy. A 26.1% increase in carbon productivity was achieved compared with the baseline scenario, whereas the coal to ethylene route should be phased-out, as more than 90% of the pollutants are generated by 10%–17% of the coal to ethylene facilities. However, CO2 emissions from ethylene will inevitably increase along with doubling ethylene production. An imbalance in pollutant generation also emerges if large-scale naphtha is exclusively promoted for ethylene plant implementation. The study provides methodological support for investigating feasible roadmaps for key product capacity expansion, and has practical meaning for high-quality industrial development domestically and globally.