Water Reuse through Membrane Technologies for a Dairy Plant Using Water Pinch Simulation Software

The main goal of this study is to evaluate possible reuse routes of effluents from adairy plant. First, the water flow in the plant was evaluated. All water consumed and effluents generated by the industrial process were quantified and characterized. In addition, the water quality parameters required for different industrial activities were assessed. Secondly, a treatment system using a membrane bioreactor and a nanofiltration reactor, from a study previously conducted by the authors, was considered. Then, a water pinch analysis was carried out through the application of the collected data using the Water Pinch software. Both direct reuse/recycle and regeneration schemes were investigated. In this context, although the direct reuse/recycle of effluents were shown to be able to reduce the freshwater use for the clean-in-place process (CIP) by 33.4%; the schemes with the regeneration of the effluents showed up to 66.7% and 95.4% of freshwater reduction for the CIP and general processes, respectively. Finally, four water reuse routes were proposed. The proposed route combining the most advanced treatment technologies studied showed the best performance in terms of reduction of the total freshwater consumption (69.5%) in the dairy plant.