Satoshi Ohnishi

The Impact of Scale, Recycling Boundary, and Type of Waste on Symbiosis and Recycling

Innovative waste recycling through industrial processes such as industrial and urban symbiosis has long been practiced and recently received much attention in the field of industrial ecology, with researchers making efforts to identify key contributing factors to successful industrial symbiosis. By analyzing 88 sample recycling projects in 23 eco‐towns in Japan, this article focuses on the factors of project scale, recycling boundary, and types of waste in relationship to environmental benefits and operational performance. The results showed that larger eco‐towns achieved more savings of virgin materials and higher stability in operation. Large‐scale projects tended to locate closer to the users of recycled products than did small‐scale projects. For treating similar types of waste, projects producing recycled products for special users (e.g., feedstock to a blast furnace for iron production) tended to locate closer to the users than those not producing for special users. The type of waste had a strong effect on the savings of virgin materials and recycling boundaries, while local factors had significant impacts on operational performance. The results also showed that agglomeration did not significantly contribute to the environmental benefits or operational performance of eco‐town projects. Another finding was that national agencies were helpful for facilitating cross‐prefecture transportation and long‐distance transaction of wastes. Implications of the findings are also discussed.

Evaluation and Allocation of Greenhouse Gas Reductions in Industrial Symbiosis

Summary Industrial symbiosis (IS) exchanges have been recognized to reduce greenhouse gas (GHG) emission, though methods for quantification of GHG emissions in IS exchanges are varied, and no standardized methods are available. This article proposes a practical approach to quantify total and allocated GHG emissions from IS exchanges by integrating the GHG protocol and life cycle assessment. The proposed method expands the system boundaries to include all IS companies, and the functional flow is set to be the sum of the main products. The total impact of a company is allocated to the main product. Three by-product impact allocation methods of cutoff, avoidance, and 50/50 are proposed, and the total and distributed impacts of the IS systems in an industrial park are theoretically derived. The proposed method was tested to quantify GHG reduction in a real IS exchange developed between Korea Zinc (a zinc smelter) and Hankook Paper (a paper mill company) in the Ulsan Eco-Industrial Park initiative. The total reduction of GHG emissions in this IS exchange, 60,522 tonnes of carbon dioxide per year, was the same in the GHG protocol, whereas GHG distribution between two companies depended on the allocation method. Given that the reduction of GHG emissions from IS exchanges is the product of the collaboration of giving companies and receiving companies, the 50/50 allocation method is best from an equivalent-responsibility and benefit-sharing perspective. However, this study suggests a more practical implementation approach based on a flexible and negotiable method of allocating the total GHG reduction between stakeholders.

ECO-INDUSTRIAL DEVELOPMENT AS A CIRCULARIZATION POLICY FRAMEWORK TOWARD SUSTAINABLE INDUSTRIAL CITIES. LESSON AND SUGGESTIONS FROM THE ECO TOWN PROGRAM IN JAPAN

Eco-industrial development is widely considered as an effective policy and a business concept to realize sustainable circularization through collaborative networks among industries. Japanese government has accumulated practices as its national Eco Town Program in 26 cities since 1997. The operation of facilities and policy implementation have provided lessons and suggestions particularly for industrializing cities who desperately seek for the sustainable solutions achieving environment management and economic growth simultaneously. This paper aims to review the policy framework as well as accomplishments of the Eco Town Program and to provide lessons and suggestions for industrial cities’ management. We reviewed and analyzed the experience of the Eco Town Program for a decade from viewpoints of the policy framework and circular situation; and provided general implications such as combination of recycle technologies and social system, symbiotic network among recycle entities and energy intensive industries as well as suitable locational planning.