Technical Bulletin No. 0199: Treatment of Pulp Mill Effluents with Activated Carbon

This technical bulletin was first issued in 1967. It summarizes the results of an investigation of the use of activated carbon for upgrading kraft mill effluent quality conducted at the National Council's Southern Regional Center, then located in the Department of Chemical Engineering at Louisiana State University. Results obtained at that time indicated that activated carbon could be considered for application primarily as a polishing treatment, following removal of the bulk of the color bodies contained in the waste by a more economical means. However, carbon was capable of producing water of very low color and sparkling clarity. Slurry contact rather than column filtration was the indicated method of application since particle size of the carbon was found to have the greatest effect on removal. Tests indicated that some carbons can adsorb ten percent of their weight in kraft effluent constituents. Since that time extensive studies have been conducted by St. Regis and several other member companies, exploring further the capability of carbon for removing organic components, particularly those contributing color, from kraft effluents. The National Council is also currently completing a study at the New York State College of Forestry seeking to identify the basic mechanisms by which activated carbon removal of organic materials from bleached kraft effluent is affected.