Regeneration of polymer and ceramic modules with the use of recovered single-phase detergent. Dairy industry case study

The effectiveness of recovered washing compositions containing single-phase detergents from cleaning-in-place (CIP) systems as solutions for the regeneration of membrane modules fouled during the filtration of wastewater from the prerinsing of the production line (white water) was assessed. The influence of process parameters (regeneration time, transmembrane pressure, cross-flow velocity, and solution temperature) on relative flux recovery was evaluated. A significantly higher regeneration efficiency of the ceramic and polymeric modules was obtained for the alkaline detergent compared to that of the acid formula. The key process parameters for the regeneration cycle were the contact time of the module with the cleaning detergent and its temperature. The influence of transmembrane pressure and cross-flow velocity on module permeability was negligible. Filtration experiments with white water confirmed that the membrane separation process is suitable for the recovery of milk compounds from dairy effluents.