Treatment of red wine vinasses with non-conventional substrates for removing coloured compounds

摘要

Vinasses from the wine industry were treated with different materials to remove colour as a firstnstep for treatment. Peat, several composts and red mud from bauxite refining were evaluated asnadsorbents for coloured compounds, and their performances compared to that of activatedncharcoal. Among the materials assayed, grape marc vermicompost gave the best results,nfollowed by peat. A sharp decrease of absorbance between 400–800nm took place in vinassesnafter the treatments with these two materials, whereas the other substrates did not reduce thencolour of the vinasses as did activate charcoal, grape marc vermicompost and peat. Moreover,ngrape marc vermicompost and peat were activated on high temperatures or grinding, producingnbetter results in colour removal, although with negative effects on the electrical conductivity andnnutrient concentration in the wastewater. The results of the treatment of vinasses with activatedncharcoal were reproduced and even overcame, in the case of the reduction of the optical densitynof vinasses at 665 nm, using grape marc vermicompost.