Novel Cost-effective Production of High Quality Papers

Mechanical pulping accounts for about 25% of the wood pulp production in the world today. This volume is expected to increase in the future. Mechanical pulping, with its high yield, is viewed as a way to extend these resources. However, mechanical pulping is electrical energy-intensive (a mill processing 300 tons of pulp/day spends about $10 million in electricity cost) and yields paper with less strength. Biopulping, defined as the fungal treatment of wood chips prior to mechanical pulping, overcomes both of these problems. Unfortunately, the process reduces the brightness and opacity of resulting biofibers. High brightness and high opacity are highly desirable for the production of high quality papers. Fiber loading is a technology in which calcium carbonate is deposited onto the surface and inside the fibers, which increases the brightness and opacity of papers significantly and thus has the potential of solving both problems associated with biopulping. Therefore, the proposed research is directed at demonstrating the technical and scientific feasibility of combining the two newly-developed technologies. Both mechanical (control and biofibers), and softwood bleached kraft pulps will be subjected to fiber loading to produce high quality papers.