Coupling of molten salt heating tire pyrolysis process with carbon black modification process: Technical economic evaluation and life cycle assessment

Abstract

Previous research proposed a molten salt heating tire pyrolysis reactor, based on the high heat transfer and storage capabilities of molten salts, to enhance heat transfer and improve the quality of pyrolysis products. During the pilot and industrialization stage, the techno-economic analysis (TEA) and life cycle assessment (LCA) are crucial to evaluate the economic potential and the environmental impact characteristics. This study conducted a TEA and LCA based on the molten salt heating tire pyrolysis process coupled with a carbon black modification process, relying on data from a process-level demonstration project. TEA results show that the unit disposal cost per ton of tire is 2090.6 RMB. The financial internal rate of return (FIRR) is 19.62%, and the payback time (PBT) is 5.87 years. The LCA results show that the molten salt heating tire pyrolysis process has a positive impact on global warming, emitting 224 kg CO₂ equivalent for every ton of waste tires disposed of. When considering product substitution, the greenhouse gas emissions for this process are −1292.2 kg CO₂ equivalent, demonstrating high environmental benefits. This paper is of significant reference value for the practical operation of the molten salt heating tire pyrolysis process in industry.