Low-carbon retrofit strategies for BF-BOF integrated steel plants considering carbon price dynamics: An analysis under different budget scenarios

This paper investigates low-carbon retrofit strategies for BF-BOF integrated steel plants under different budget levels, considering carbon price dynamics. An optimization model that incorporates carbon price is developed to select technology portfolios from 22 prevailing technologies and provide the retrofit strategies under high, medium, and low budget levels. The dynamics of carbon prices are incorporated based on expert forecasts and survey data, reflecting expected long-term trends and market volatility in China’s carbon trading system. Under these budget scenarios, the economic and environmental performance of the resulting strategies is then evaluated in terms of their expected returns, annual CO2 reductions, and post-retrofit emission intensity. A process-level analysis further reveals that investment allocation and decarbonization characteristics vary across budget levels. Furthermore, robustness and sensitivity analyses confirm the stability of the main results under alternative parameter settings. These findings provide practical insights for steel enterprises to design adaptive low-carbon retrofit strategies that account for their investment capacities and the evolving carbon price.