Treatment of Bleaching Effluent From the Pulp and Paper Industry by Photcatalytic Oxidation

We investigated the photocatalytic degradation of COD in bleach plant effluent in a low-cost, nonconcentrating shallow pond slurry reactor using artificial UV light. We studied the photocatalytic oxidative degradation using Degussa P25 titatium dioxide (TiO2). Effects on degradation of catalyst loading, initial COD values, UV intensity, and aperture-to-volume ratio of the reactor were studied. Degradation rates were strongly influenced by some of these measures. Treatment efficiencies declined with a decrease in UV light intensity and increased with an increase in aperture-to-volume ratio. Results obtained in sunlight were similar to those obtained under artificial UV light in the laboratory.