Fish Processing Wastewater

THE UTILIZATION OF SLUDGE GENERATED IN COAGULATION OF FISH PROCESSING WASTEWATER FOR LIQUID FEED PRODUCTION 215... 

Key words Fish processing wastewater, post-coagulation sludge, fish silage. 

In our experiments the coagulation of fish processing wastewater was performed using ferric sulfate. The sludge generated in this process has been added for silage production. The sludge characteristics are presented in Table 3. 

In fish processing plants, a huge amount of wastewater is generated. The main components of this wastewater are proteins and fats, substances of nutritious value. 

The annual discharge of protein and fat with wastewater from fish processing sector in Poland is presented in Table 2. 

Table 2. Protein and fat annual discharge with wastewater from fish processing industry in Poland...

Usydus, Z., Bykowski, P.J., The utilization of waste and raw materials obtained in wastewater from the fish processing industry, Bulletin of the Sea Fisheries Institute, nr 1 (143), 1998,17. 

The process has two main sources of waste water. These are the condensate streams from the steam strippers. The principal pollutant in both wastewater streams is phenol. Phenol is of concern primarily because of its toxicity, oxygen depletion, and turbidity. In addition, phenol can cause objectionable taste and odor in fish flesh and potable water. 

In Table 1, the loads of particular pollutants discharged to wastewater from production of various processes of fish products are presented. 

Occasionally, the phosphate slime is difficult to settle in the lagoons because of its true colloidal nature, and the use of calcium sulfate or other electrolytes can promote coagulation, agglomeration, and settling of the particles. Usually an addition of calcium sulfate is unnecessary, because it is present in the wastewater from the sand-flotation process. Generally, it has been shown [33] that the clear effluent from the phosphate mining and beneficiation operation is not deleterious to fish life, but the occurrence of a dam break may result in adverse effects [19]. 

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