A business model of simulation-oriented process design is presented, including life cycle assessment (LCA) and related activities such as mulit-objective decision making. Type-zero method of integrated definition language (IDEF0) is employed as an activity modelling tool to describe the entire business model. The whole design procedure is described hierarchically With focus oil LCA related activities i.e., perform LCA is defined as a sub-activity of evaluate processes which is further a part of the top level activity, design chemical process. The economic evaluation is defined as an activity concurrent to LCA, enabling multi-objective evaluation and optimization of the process. The roles of decision-support activities Such as sensitivity or uncertainty analysis are discussed in detail. Use of IDEF0 enabled detailed and at the same time transparent definition of the whole design procedure. A case study is performed oil the design of chemical recycling processes of beverage PET bottles, which is currently an important topic in Japan. The proposed design procedure is demonstrated step by step, with focus on the multi-objective process assessment. Among several alternatives the Pareto-optimal ones are identified.