Water is an important resource for the dairy industry, both for production processes and cleaning activities. Rising concerns about water scarcity and pollution have necessitated the dairy industry to utilize available water resources judiciously and to valorize and dispose effluent streams in a sustainable manner. While financial benefits of reducing water consumption are significant, companies also benefit from a positive image due to increased environmental performance. In this context, many dairy plants have started recycling spent water streams to meet water demands of various production, heat transfer, and cleaning processes. However, installation and operation of treatment technologies often entail a significant financial burden. Intelligent decision support is therefore necessary in order to plan production operations and consider at the same time various water reuse and disposal aspects. Both of these topics have been addressed individually in the literature and have seen successful implementations. However, a key challenge is to achieve water management goals without compromising on production efficiency or product quality. This requires an integrated consideration of both production planning and water management in a single framework that is capable of evaluating tradeoffs between production efficiency and water efficiency.

We develop a production planning framework based on mathematical programming and integrate water management decisions at various levels of the decision-making hierarchy. We model quality of water resources, both fresh and used, with a flexible classification scheme that can effectively include water reuse and treatment possibilities. We demonstrate the applicability and performance of our approach in a case study based on a cheese production plant.

Overall, our framework is able to plan both production and water reuse in an efficient manner and can reduce the water footprint of dairy plants.