Products end-of-life scenario modelling using linear algebra

Abstract

There are several options at the end-of-life (EOL) of a product: reuse/part reclamation, remanufacturing, recycling, incineration (with or without energy recovery) or disposal to landfill. Each option has an economic, an environmental and a social impact. The impacts are depicted by indicators that have specific values for each option. A set of indicators’ values specific to an EOL option represents the components of that EOL option’s vector. As the three dimensions (environmental economic and social) of each option are important, one vector for each dimension needs to be considered. A generic EOL scenario, which may comprise a combination of EOL options can be expressed as a linear combination of options. Therefore, considering the percentages of a product reaching each EOL option as scalars, and the vectors associated to the options, vectors associated to the whole scenario can be calculated. This modelling approach permits the use of linear algebra tools in expressing and solving problems related to EOL scenario of products. Such a model can be applied to waste from electrical and electronic products. It represents the foundation in designing the structure of transaction-processing information systems. The model provides not only information about the environmental, economic and social impact of a certain EOL scenario, by applying the linear programming theory, it can also calculate the best scenario structure given the targets set by different laws and regulations such as the European Union Waste Electrical and Electronic Equipment (EU WEEE) Directive and the EOL options vectors. The model can be also used as a ‘What If’ support tool for decision-making showing possible results as a consequence of the influence of different factors (e.g. change of technology, different quantity of products, etc.).