A Study on the Inherent Safety for Sustainable Process Design Based on Fuzzy Logic

Abstract

Designing more sustainable processes is one of the key challenges for sustainable development of the chemical process industry. However, there is no general methodology or framework to guide sustainable process design and almost no practical experience. Especially, although economic analysis has been performed for feasibility study to improve process synthesis and design, environmental and social/safety aspects are not considered for development of process design. This thesis proposed new evaluation methods and frameworks to utilize inherent safety as an indicator of sustainability, in attempt to contribute to this emerging area. The proposed method is based on the fuzzy logic to overcome limitations and problems of existing methods. This approach illustrates three examples; first, the evaluation of inherent safety of methyl methacrylate production process compared with existing indices and experts opinions, second, the design case study of acrylic acid production process from selection of reaction route to process synthesis, and last, the selection of absorbents for CO2 capture process with economic and environmental aspects in sustainability. The case studies show how to utilize inherent safety as an indicator for safety evaluation in sustainability, how to use the obtained information to make the design more sustainable, etc. The proposed methods and frameworks show the possibility and applicability of inherent safety and sustainability in the process design. Also it can be applied to the development and synthesis of sustainable process. It can become a guideline for decision makers in designing chemical process when the safety and economic benefits collide together because of legal issues and practical engineering reasons. It makes easy to affect the process configuration and inherent safety in the conceptual design phase than in the later phase of process design.