Reducing carbon emissions through industrial symbiosis: a case study of a large enterprise group in China

Industrial symbiosis (IS) can promote carbon emission reduction through effective use of resources and energy. This study aims to quantitatively examine the effects of IS performance on carbon emission reduction through a case study on Xinfa Group, a comprehensive large enterprise group in China. A scenario without IS is assumed for comparison. Results show that the carbon emission rates with and without IS are 16.20 Mt of CO2e and 18.17 Mt of CO2e, respectively. The largest carbon emission sector is the electrolytic aluminum industry, which accounts for 70.2% of the total. The carbon emissions under the IS condition at Xinfa Group decrease by 10.84% compared with that under the no IS condition. The carbon emission reduction primarily results from byproduct exchange and energy symbiosis, with rates of 72% and 28%, respectively. Carbon emission reduction as a result of energy-graded utilization is 11.4%. Carbon emission reduction from calcined lime, alumina, calcium carbide, and other industries accounts for 60.7%, 18.7%, 0.9%, and 27.1% of the total emission reduction, respectively. The characteristics of IS development at the Xinfa Group are presented.