Catalase and Peroxidase Control to Improve Bleach Plant Efficiency, 1996 Pulping Conference Proceedings
L. R. Robertson
T. W. Nahley
Nalco Chemical Co.
Peroxide bleaching efficiency is adversely affected by microbial contamination. Although peroxide is biocidal at high doses, significant numbers of pulp and paper mill bacteria produce enzymes such as catalase that consume peroxide at typical mill use levels. In lab and field studies, it was discovered that addition of a selected proprietary biocide reduced the catalase producing bacterial population. This, in turn, reduced peroxide demand. Even with reduced peroxide usage, brightness and peroxide residuals increased. Before the trial, peroxide residuals were undetectable in the process waters. By treating the process water with the proprietary biocide, peroxide could be detected at 490 ppm. Another benefit was a decrease in sodium silicate use. Key Words: Bacteria, biocide, bleaching, brightness, catalase, closure, deinking, enzymes, peroxide, pulp.
Catalase and Peroxidase Control to Improve Bleach Plant Efficiency, 1996 Pulping Conference Proceedi