Publications

Reverse osmosis (RO) is essential for dairy processors to reduce their water input and the energy dedicated to dewatering processes such as evaporation. Indeed, water can be reclaimed by RO from numerous dairy fluids (e.g., milk, cheese whey, UF permeates, condensing water), but these applications may have different effects on plant efficiency in terms of water and energy use. Consequently, this study uses predictive analysis to evaluate the impact of performing RO at different steps in the process flow chart of an industrial cheesemaking plant. The hypothesis that preconcentrating milk by RO at the entry-gate of the plant (on skim milk) would reduce the volume of by-products to be processed, and the resources used, was not valid. Instead, the most efficient way to reduce the amount of resources consumed was to perform RO on the cheese whey and milk UF permeate prior evaporation. Preconcentrating these by-products to a total solids content of 20% and 22%, respectively, reduced the entire natural gas consumption by 36% and the electricity consumption by 10%, compared to a scenario where only condensing water was reclaimed.