Quantification and characterization of effluents from the seafood processing industry aiming at water reuse: A pilot study

Abstract

In the face of a major global drinking water crisis, it becomes increasingly important to raise concerns on the use of sustainable techniques, mainly those aiming at saving potable water, especially in the seafood industry, that consumes significant amounts of water resources. In this context, the aim of the present study was to carry out industrial water management, quantifying and qualifying effluents from the general activities of a seafood processing industry, in order to identify which effluent exhibited reuse potential. Water use (water balance) was measured at six fish processing steps, and effluent physicochemical and bacteriological analyses were carried out. Direct reuse was not indicated for any of the analyzed effluents, mainly due to high levels of total coliform bacteria (104 to 107 MPN/100 ml). However, indirect water recycling and reuse can potentially be applied after a simple effluent primary treatment and disinfection from the freezing tunnel and cooling chamber defrosting, in order to supply cooling tower demands. This practice may reduce the total average water consumption of the processing unit by 11% and, if the effluents from the cooling tower purges were to also be reused for other administrative ends, this reduction may reach 21.9%, enhancing the competitiveness of this industry and preserving fresh drinking water.