On the importance of integrating alternative renewable energy resources and their life cycle networks in the eco-design of conventional drinking water plants

Abstract

The eco-design of industrial processes is confronted with several key requirements: the proper definition and combination of Process Modelling and Life Cycle Assessment (PM-LCA methodology), the complete integration of alternative raw materials and renewable energy resources and their life cycle networks, and the efficient multi-objective optimization of the whole process including the supply chain. In order to respond to these requirements, this work extends the structure of the PM-LCA framework by also involving the life cycle networks of various energy resources and raw materials. In addition, and due to the computational complexity of such a combined platform, an appropriate multi-objective optimization strategy, dubbed AMOEA-MAP and dedicated to expensive black-box problems, is used to attain the Pareto-optimal solutions for design with a fixed computation budget of 200 function evaluations for a bi-objective problem (cost - environmental impacts).The successful application of such a methodology is then demonstrated for a conventional drinking water production plant, by optimizing a set of mixed-integer decision variables comprising both real-type operating conditions and integer-type design parameters related to the choice of relevant raw materials and renewable energy resources (heat and electricity). The results also show an additional improvement by a factor of five in the overall economic and environmental performance of the optimized plant when alternative renewable energy resources are included.