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1 Introduction
Due to the massive industrial expansion and the ever-frequent product turn-over, the disposal of end-of-life products at a large-scale represents a major challenge to the modern society. Green industry aims to protect environment and reduce natural resource consumption. Ilgin and Gupta (2010) summarize environmentally conscious manufacturing and product recovery in four aspects and disassembly is included. Disassembly is an important process in product recovery and it allows for the selective separation of desired parts and materials (Lambert and Gupta, 2005). A literature review of green supply-chain management (Srivastava, 2007) takes an integrated and fresh look into the area to reduce the ecological impact of industrial activity without sacrificing quality, cost, reliability, performance or energy utilization efficiency. An important aspect of disassembly for green operation is to find efficient disassembly process scheduling (Dowie, 1994). Thus, a feasible and effective disassembly sequence planning (DSP) method is always required for product disposal. Product disassembly and recycling are essential for green industry development. Therefore, DSP plays a critical role in industry chain nowadays. DSP refers to a process that establishes the proper disassembly sequence for a given product. The conventional disassembly only removes the joints between the components, threaded connection, without destroying the entire product. In contrast, the destructive disassembly completely destroy the whole target product into pieces followed by further recycling process. Partial destructive disassembly, as indicated by the name, will only destroy the connectors and the low valued components. Since every component will be destroyed eventually in the destructive disassembly mode, there is no need to do planning. Therefore, from the practical point of view, DSP is mainly conducted in two modes, namely, the conventional disassembly mode and the partial destructive disassembly mode.
In the research literature, DSP in conventional disassembly mode has been studied extensively. In terms of DSP, disassembly models are usually graphs or matrices. Approaches such as disassembly matrices (Huang and Liao, 2009), disassembly hybrid graph model (Zhang and Zhang, 2010), Petri net (Kuo, 2012), disassembly constraint graph (Li et al., 2006), and so on, are developed. The graph or matrix based models are suitable for structure analysis and simple path planning, but problems will become very complicated in terms of the actual disassembly situation. Therefore, advanced algorithms or methods have...