Effluent Loads From Different ECF Bleaching Sequences Used In Hardwood Kraft Pulp Bleaching
نویسنده
چکیده
Effluent loads from different traditional and emerging ECF bleaching sequences were investigated. Oxygen delignified Eucalyptus camaldulensis and Acacia mangium kraft pulps having similar kappa number, ca 12.0 were used in this study. Different ECF bleaching sequences were compared with reference sequence, D0EopD1 in terms of effluent load, such as AOX, COD and TOC. Depending on the nature of sequences 6.0 to 63.0% chlorine dioxide consumption was reduced and as a result the amount of AOX formation was also reduced. The effluent from sequences (DZ)EopD1, DHTEopD1, AhotD0EopD1, Ahot(DZ)EopD1 and ZEopD1 showed marginally higher COD and TOC in comparison with reference sequence, D0EopD1. Sequences like, D0EopQ(PO) and (DZ)EopQ(PO) having (PO) instead D1 of reference sequence reduced AOX in effluent substantially; but COD and TOC loads were increased. In all cases acacia gave marginally higher effluent loads compared to eucalyptus.
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