ABSTRACT
       Cod desalting is an operation that involves mass transfer processes, where mainly Na+ and Cl- ions and soluble proteins are transferred. Thus environmental management of this effluent is needed. The membrane technology is an option that allows concentration of these solutions and the selective separation of its components.
       The aim of this work was the study of the technical feasibility of membrane technology treatment of residual brine coming from the cod desalting for improving environmental management. The residual brine used in different experiments was obtained from the desalting of salted cod fillets in a mass ratio of 1:7 of cod:water.
Analysis of mass transfer phenomena suggested that the main components transferred during cod desalting were water and NaCl and to a lesser extent, proteins and nitrogenous substances. Dead-end filtration experiences showed that the pH of the brine directly affects the charge of proteins and therefore the electrostatic repulsion between molecules. We determined that the best pH condition (higher permeate flux and lower presence of SV in permeate) was 6.5. Both for the MF and the UF was established that the pressure is decisive in the permeate flux and membrane fouling. The MF as pretreatment has a wide pressure range in which J is driven by the driving force, however involves an additional cost. The results of the experiences of UF concentration mode showed that the protein rejection rate was over 98%, while COD dropped by 27 с 2% and BOD5 by 74яся1%. The results demonstrate the technological feasibility of the application of membrane technology in the removal of colloidal particles present in the residual brine from the cod desalting. The effectiveness and efficiency of process will depend on the operating conditions used, which highlights the importance of studying the effect of these conditions on the flux density (J) and the fouling of membranes, achieving process performance compatible with membrane useful life.