4. Conclusions
Activated sludge was tested for biological treatment of fish canning industrial wastewaters. The statistical experimental design and response surface methodology were found to be efficient tools to optimize some parameters. The optimum conditions in the ranges studied were found to be a HRT of 6.42 h and an initial DOC of 406.2 mg/L, being the HRT the factor that most affected the DOC removal of the effluent.
This work showed the feasibility of using an activated sludge biological treatment to reduce significantly (88%) the organic content present in fish canning industrial wastewaters. Depending on the purpose for the treated water, it might or might not be necessary further polish treatment.