EFFECT OF CHLORINE DIOXIDE SUBSTITUTION, OXYGEN DELIGNIFICATION, AND BIOLOGICAL TREATMENT ON BLEACH-PLANT EFFLUENT

The study examines the effects of chlorine dioxide (ClO2) substitution , oxygen delignification, and biological treatment on pollutant levels in simulated bleach-plant effluents. Biological treatment reduced COD , BOD, AOX, and toxicity but did not reduce color. ClO2 substitution r educed discharge of all five pollutants, with a large reduction in AOX Substitution did not influence the efficiency of pollutant removal by biological treatment Oxygen delignification reduced discharge of the five pollutants, and effluents from sequences with oxygen delignificat ion were easier to treat by aerobic methods.