Retrospective and prospective assessment of exergy, life cycle carbon emissions, and water footprint for coking network evolution in China

Abstract

As a key upstream supplier for the most energy-intensive industries, the coking industry is a typical high energy-consumption and high emission industry. This study evaluates exergy and life cycle emissions of the coking network evolution at a temporal scale, as well as quantifies the embodied water in the industry. To provide a reasonable forecast of development patterns, four key factors were examined using scenario analysis, including industrial symbiosis, bio-production, carbon capture and storage, and energy recovery. When the coking plant was coupled with the iron and steel industry, the ammonium sulfate work zone had the maximum value of specific exergy losses in 2012. Coking contributes to 76.7% of the total greenhouse gas emissions from the network, and water use for ammonia distillation is 6.4 times greater than the rest of water use in the cold work zone. Moreover, the development roadmaps created by scenario analysis identified that electricity decarbonization displays a great potential for reducing carbon emissions; however, structure adjustment of the coking industry alone could not achieve the 2030 climate target. To enhance energy utilization and reduce emissions, this work shows the necessity of decreasing independent coking enterprises in China and identifies improvement potentials in the coking network.