S U M M A R Y
The present study describes the alternative treatments applied to the secundary effluent of a bleached kraft process pulp industry. The effluent samples were analysed in relation to their contents of chloride and trace elements (zinc, copper, lead and cadmium), and submitted to a treatment with aluminium sulphate or iron chloride, as floculants, using further, solid residues of industrial process (dreg, grit and heavy ash) and active carbon, as coagulation adjuvants. A significant reduction of the contents of chloride and trace elements in the final effluent was observed by the combined use of aluminium sulphate/active coal 2 and iron chloride/industrial residues, respectively.
Key words:
Effluents from pulp industry; trace elements; chloride