Sustainable Process Synthesis-Intensification

Abstract

Sustainable process design can be achieved by performing process synthesis and process intensification together. This approach first defines a design target through a sustainability analysis and then finds design alternatives that match the target through process intensification. A systematic, multi-stage framework for process synthesis-intensification that identifies more sustainable process designs has been developed. At stages 1-2, the working scale is at the level of unit operations, where a base case design is identified and analyzed with respect to sustainability metrics. At stages 3-4, the working scales are at the levels of unit operations, tasks and phenomena. Here, first intensified flowsheet alternatives are generated through a tasked-based process synthesis method where tasks performed in unit operations are identified, analyzed and recombined through a means-ends analysis. Next, a phenomena-based process synthesis method is applied, where the phenomena involved in each tasks are identified, manipulated and recombined to generate new and/or existing unit operations configured into flowsheets that are more sustainable from those found in the previous levels. An overview of the key concepts and the framework are presented together with the results from a case study highlighting the application of the framework to the sustainable design of a production process for dimethyl carbonate.