BIOPULPING PROCESS DESIGN AND KINETICS

Biopulping is the solid-state fermentation of wood chips as a pretreat ment for mechanical pulping processes. The two organisms that are curr ently of the greatest interest for biopulping are the white-rot fungi, Phanerochaete chrysosporium and Ceriporiopsis subvermispora. P. chrys osporium has been shown to successfully biopulp wood (33% energy savin gs; 39% improvement in tear index) without the need for sterilization of the wood or nutrient supplementation. Demonstrating the practical a nd economical feasibility of the biopulping process requires process m odeling based on accurate kinetic data. Techniques to monitor dry weig ht loss and growth rate as functions of time using carbon dioxide prod uction data have been developed. Growth was shown to be linear with ti me on unsupplemented chips and exponential with time on supplemented c hips.