Integrated Forest Biorefinery

Abstract

The development of an integrated forest biorefinery (IFBR) would enable the industry to increase its revenue by producing bio-energy and new biomaterials in addition to traditional wood, pulp, and paper products. The IFBR concept also addresses the societal need to use renewable resources rather than fossil fuels to produce commodity products, liquid fuels, and electricity. The initial visualized IFBR would be based on sulfur-free, alkaline pulping of hardwood with an alkaline hemicellulose extraction step prior to pulping and spent pulping liquor gasification and lignin precipitation after pulping. New products from an IFBR based on alkaline pulping include electric power, new wood composites, liquid fuel, ethanol, chemicals, and polymers. Pre-extraction generates a feed stream for new bioproducts, while decreasing alkali consumption, increasing delignification rate, and reducing black liquor load. Black liquor gasification and/or lignin precipitation are an integral part of the IFBR with the synthesis gas and precipitated lignin being the feed for liquid fuel and carbon fibers, respectively. The additional energy requirements of the IFBR would be met by gasification/combustion of waste biomass. The key to the successful implementation of the forest biorefinery is to identify possible products that can be economically produced by a pulp and paper mill. Process integration tools can be used to identify these products. A roadmap can be developed once the products have been identified. The successful implementation of the forest biorefinery will likely be mill specific, and will in many cases require strategic collaborations with experts.