Life cycle option selection of disassembly parts for material-based CO2 saving rate and recovery cost: Analysis of different market value and labor cost for reused parts in German and Japanese cases

Global warming is the major global environmental issue. To achieve less greenhouse gas emissions with circular economy for manufacturing assembly products, the key is to recovery including reuse and recycling End-of-life (EOL) products. Since reuse and recycling can avoid manufacturing of virgin materials, life cycle options such as reuse, recycling and disposal for each part entailing manual disassembly which is in high cost, the disassembly parts selection is carried out to decision for reuse and recycling the EOL assembly product environmentally and economically. Additionally, in the reuse of an assembly product, the revenue by reusing are different among each country owing to the differences of the second-hand market prices and labor cost by disassembly among the countries. This paper proposes a life cycle option selection of disassembly parts for material-based CO2 saving rate and recovery cost with different market value. Each part is selected from reuse, recycling and disposal to harmonize the material based CO2 saving rate and the cost. First, the procedures for designing the disassembly parts selection is presented, and life cycle option selection using 0-1 integer programming with the epsilon constraint method is formulated. Next, a numerical experiment of the results of the disassembly parts selection in the case of a computer is conducted. Finally, owing to the differences of sales revenue by parts reuse in the second-hand market prices, cases of Japan and Germany are examined for establishing multi-value circulation.