Wastewater generated as a result of the fish brining process has a very high contamination load. Application of appropriate technologies of wastewater treatment in order to reuse it in the production process once the NaCl content has been supplemented can provide an alternative to its costly recycling. The experiment included ultrafiltration tests conducted on waste brine originating from food processing industry. The results of physicochemical tests indicated very high reductions of fat content (100%) and turbidity (99.8%). Reductions were also revealed in the case of other indicators, i.e., chemical oxygen demand, biochemical oxygen demand, protein and histamine content: by 24.4, 35.2, 27.6 and 22.7%, respectively. Furthermore, it was reported that the obtained permeate retained its quality and microbiological stability. The studied ultrafiltration (UF) process can be successfully used for recirculation of brine in salted fish processing, and at the same time constitute an easily monitored critical control point in the hazard analysis and critical control point (HACCP) system.

Practical Applications

Fish processing industry is characterized by very high water consumption for technological purposes and generates a considerable amount of wastewater burdened with organic matter and mineral compounds (mainly sodium chloride). Such wastewater is usually released to the common sewage system. An alternative solution would be to release it into a recirculation system. This solution can be made possible by membrane separation technologies. The application of the UF using ceramic membranes allows to obtain high-quality brine which can be successfully reused in the production process after the NaCl content has been replenished. Moreover, introduction of the UF technology meets the requirements of the HACCP system.