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.