Water system integration and optimization in a yeast enterprise

Water system integration is an effective way to save freshwater and reduce wastewater in enterprises. Water system integration treats the water system in an enterprise as a whole and utilizes water resources more effectively by optimizing the water utilization network. In this study, water system integration was applied to a yeast enterprise. According to the characteristics of the water utilization processes in the yeast enterprise, the water utilization processes were classified as fixed-load, fixed-flow, no-output flow, and no-input flow processes. Optimization schemes for the no-output flow and no-input flow processes were obtained through qualitative judgment. Optimization schemes for the fixed-load and fixed-flow processes were obtained using a mathematical programming method. Through the adjustment of the water utilization network, it was demonstrated 27% of freshwater consumption could be saved and 23% of the COD could be reduced. (C) 2015 Elsevier B.V. All rights reserved.