Environmental and economic gains of industrial symbiosis for Chinese iron/steel industry: Kawasakiʹs experience and practice in Liuzhou and Jinan

With material and energy flow features, iron/steel industry has unique advantage in the industrial symbiosis (IS) formation to realize environmental and economic benefit simultaneously. The quantification of the scale and significance of IS benefits is valuable for IS promotion, while there is much few attention to it, especially in China. Under this circumstance, this paper evaluates and compares the number, scale and the related environmental/economic gains of IS activities in iron/steel-centered industrial areas in Liuzhou and Jinan in China, and Kawasaki in Japan. Results show that: in Liuzhou, there are three symbiosis activities between industries. The annual by-product/waste exchange is more than 2 million ton/y, gaining economic revenue more than 36.55 million USD for the iron/steel company. In Jinan, seven symbiotic links are between industries, and two are between urban community and iron/steel plant. The total by-product/waste exchange is over 8 million ton/y and the economic gains account to 158 million USD. In Kawasaki, iron/steel industry relates to four symbiotic links, the total by-product/waste exchange amount is about 500 kton/y, with the economic gains over 54 million USD. The form and the complexity of the IS network are different in the three cases. IS in Liuzhou and Jinan are with the features of large number and scale, but single types. While in Kawasaki, IS includes not only traditional exchanges between iron/steel plant and the other industries, but also the innovative utilization of urban refuse by industrial area. Finally, from the perspective of technology, legislative framework and support policy, circular technology inventory, integrated waste management system, information platform and national subsidies are needed to support the ever-improvement of IS promotion in Chinaʹs iron/steel industry.