Keywords: life cycle assessment, allocation problem of environmental consequences, related process model, BI-, allocation
Study of a methodology for life cycle assessment using a related process model
In recent years, human activities have begun to seriously influence local and global environments. Under the circumstances, Life Cycle Assessment (LCA) is expected to be a powerful tool in evaluating impacts on environments. However, LCA is not yet established methodologically or formulated systematically. The main problems are: 1. Estimation of the repercussions of the activity of a main product on others. 2. Allocation of resource consumption or emission between a main product and recycling or cascading products. 3. Allocation of resource consumption or emission between a main product and co-products in a combined production. In this context, we have developed novel LCA procedures using linear programming (LP), an allocation method using the best base inverse matrix of LP (BI-allocation) and investigated passenger cars as an example. As a result of these procedures, the repercussion effect and allocation problems are systematically calculated and it is proved that BI-allocation makes a system more suitable than allocation by product weights.