Selective disassembly and simultaneous end-of-life decision making for multiple products

Environmental protection legislation, consumer interest in "green" products, a trend towards corporate responsibility and recognition of the potential profitability of salvaging operations have resulted in increased interest in product take- back. However, the cost-effectiveness of product take-back operations is hampered by many factors, including the high cost of disassembly and a widely varying feedstock of dissimilar products. Two types of decisions must be made; how to carry out the disassembly process in the most efficient manner to "mine" the value-added that is still embedded in the product, and then how to best utilize that value-added once it is recovered. This paper presents a method for making those decisions. The concept of a transition matrix is integrated with mixed integer linear programming to determine the extent to which products should be disassembled, and simultaneously determine the optimal end of life (EOL) strategy for each resultant component or subassembly. The main contribution of this paper is the simultaneous consideration of selective disassembly, multiple products, and the value added that remains in each component or subassembly. Shared disassembly operations and capacity limits are considered. An example using two cell phone products illustrates application of the model.