Technical Bulletin No. 0107: Development on the Removal of Color from Caustic Extract Bleaching Effluent by the Surface Reaction Process – Part I
Experiments conducted by the Council*s Louisiana State University project, have indicated that practically all the color could be removed from kraft pulping and caustic extract effluents by filtration through a bed of hydrated lime. The fact that the color bodies react at the surface of the bed and when removed allow continued filtration, suggested the use of the pre-coat vacuum filter for application of the process. Bench scale laboratory tests reported in the attached Council technical bulletin appeared promising, and a large scale pilot plant has been erected and will be in operation shortly at a southern mill. From this operation, a complete evaluation of the practicability and cost of applying the process will be obtained. Laboratory work toward finding a means of obtaining higher filtration rates than those possible with the pre-coat filter are also underway at Louisiana State University.