Technical alternatives for coke oven gas utilization in China: A comparative analysis of environment-economic-strategic perspectives.

China is the largest coke producer and consumer. There is a pressing need to address the high emissions of air pollutants and carbon dioxide associated with traditional coking production. As the nation pursues a transition towards carbon neutrality, expanding supply chains for coking plants to produce hydrogen, methanol, and other green alternatives has garnered significant attention. However, the relative advantages of these strategies have remained uncertain. In this study, we integrate a life cycle assessment-economic analysis-scenario analysis model to evaluate various coke oven gas (COG) utilization routes (COGtM: COG-to-methanol, COGtLNG: COG-to-liquefied natural gas, COGtSA: COG-to-synthetic ammonia, and COGtH: COG-to-hydrogen). The results indicate that COGtSA emerges as the preferred option for balancing environmental and economic benefits. Meanwhile, COGtM demonstrates economic viability but is associated with higher environmental impacts. Despite being recognized as a significant strategic direction under carbon neutrality initiatives, COGtH faces economic feasibility and risk resilience limitations. COGtLNG encounters both financial and environmental challenges, necessitating strategic development from an energy security perspective. The projected coking capacity is anticipated to experience a slight increase in the mid-term yet a significant decline in the long term, influenced by steel production capacity. In potential future markets, COGtM is estimated to potentially capture a maximum market share of 16-34% in the methanol market. Furthermore, against the backdrop of continuously expanding potential demand for hydrogen, COGtH holds advantages as a transitional solution, but in the long run, it can only meet a small portion of the market. COGtSA can meet 7-14% of market demand and emerges as the most viable pathway from the viewpoint of balancing environmental and economic aspects and covering future markets.