Co‐benefits analysis of industrial symbiosis in China's key industries: Case of steel, cement, and power industries

Accelerating the construction of ecological civilization in the industrial field and guiding the transformation of industry toward a green direction have become a national development strategy. Promoting the coordinated development of energy-intensive industries such as steel, cement, and power is a key breakthrough in achieving the green transformation of various industries. This study has designed a steel–cement–power polygeneration system with the collaborative utilization of solid waste resources as the ecological link point. Four scenarios, including business-as-usual, optimization of product structure, low-carbon technology application, and policy advancement (PAD), were established to assess the overall energy-saving and emissions reduction potential of the steel–cement–power polygeneration system from 2015 to 2050. The results show that product structure adjustment and industrial symbiosis have a significant impact on energy saving and emission reduction of key industries. In 2050, the total energy consumption and carbon emissions of the polygeneration system could reach 38,697.64 PJ and 3766.73 Mt CO2. Based on the scenario analysis, the production and use of solid waste in the polygeneration system and the economic benefits are also discussed. Under the PAD scenario, by 2050, the proportion of fly ash as cement raw material will increase to 41%, while the supply of blast furnace slag may be insufficient, and the comprehensive utilization of solid waste can bring economic benefits of 238.32 billion Yuan to the system.