Efecto de la concentración de quitosano y ph sobre la remoción de sólidos en agua de cola de la industria sardinera

the stickwater is a complex effluent consisting of a variety of solids, most of which should be removed to produce a new effluent that can be directly poured into the sea. in this study, stickwater was centrifuged to remove solids and the resulting liquid was then treated with chitosan at different concentrations and ph to eliminate the solids left in it. centrifugation extracted 33.88% of total solids, 28.52% protein, 97.50% fat, 40% ash and 20% npn. it also decreased in 42.2 and 63.3% the bod5 and cod, respectively. transmittance percent increased from 14.6 to 18.4, a small change in relation to the content of solids removed. the addition of chitosan to centrifuged stickwater decreased 25% of the total solids content, 55% of protein, 40% fat, 24% ash and 60% npn. likewise, the addition of chitosan decreased the bod5 and cod in 48.4 and 31.2%, respectively. as a consequence, transmittance increased from 18.4 to 86.0%, indicating that such increase was mainly due to the elimination of pigments rather than organic matter. a significant decrease was achieved in bod5 and cod; nevertheless, other tools are required to reduce these figures to the levels established by the environmental health regulations.