A Greedy Search Technique for Multiple Contaminant Water Network Synthesis

One of the major impacts of climate change is the scarcity of water resources. Various techniques have been employed across different sectors to conserve water. Process integration is one of the routes adopted to save water in the process industry. In this pathway, water is reused and recycled within the industry. Raw materials used and the processes performed introduce multiple contaminants in the water streams, limiting their reuse and recycling potential. This paper develops a greedy search algorithm to identify a network for water-reusing and water-recycling streams with multiple contaminants. The proposed approach involves identifying a feasible solution and its perturbation and reconstruction to achieve an improved solution. A feasible solution is determined using the concept of concentration potentials, and then every water allocation is reduced by a factor. Using this perturbed solution as an initial point, an improved solution is reconstructed through a greedy search method. The effectiveness of this technique is shown through six examples. This algorithm obtains significant water savings in a few iterations. In the examples, the approximate solutions are quickly achieved through the proposed algorithm.