Transition Towards a Circular Economic Model in the Processes of the MIDREX-NG DRI
摘要
The global iron and steel industry plays a critical role in infrastructure development, yet it is a major contributor to greenhouse gas emissions, energy consumption, and environmental degradation. In response to increasing regulatory and societal pressure to decarbonize, the concept of the circular economy (CE) has emerged as a sustainable alternative to the traditional linear economic model. The implementation of the 4Rs—Reduction, Reuse, Recycle, and Remanufacture—was employed to evaluate the circular economy’s effectiveness, considering economic, technical, environmental, and social dimensions within the iron sector. Achieving enhanced efficiency in energy, materials, and processes is crucial for fostering a circular iron industry. This study conducted an in-depth analysis of the primary components of an iron-making plant to identify optimal production methods that minimize emissions and losses, utilizing thermodynamic simulations to evaluate operational conditions, standards, and benchmarks. The research highlighted the significant disparities between optimal and actual operational processes, revealing both challenges and opportunities for improving circularity. Simulations identified 48% energy loss from hot sponge iron and 77% waste heat in exhaust gases, while material balances revealed 6% sludge and 3% dust generation. By applying CE strategies—including waste heat recovery, process gas recycling, and sludge reduction—the study demonstrates pathways to improve energy efficiency by 38 MW and reduce material losses by 9%. AHP (Analytic Hierarchy Process)-SWOT (Strengths, Weaknesses, Opportunities, and Threats) prioritization further highlights regulatory alignment and technological retrofitting as critical for achieving sustainable targets. SWOT and AHP analyses were employed to assess the industry’s current state and prioritize resource and waste management, thereby facilitating informed decision-making and advocating for advancements in governance related to development, investment, research, and technology enhancement for circularity. Ultimately, a comprehensive model for implementing a circular economy in the iron-making sector was developed for the first time to provide a roadmap for implementing circular economy strategies in Direct Reduced Iron (DRI) plants, contributing to the broader goal of achieving net-zero emissions in the iron and steel industry.