Valorization of crude tall oil derived at softwood Kraft Mills

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Crude tall oil (CTO) generated as a by-product from the pulp and paper manufacture using coniferous wood (softwood) by the Kraft pulping process contains 30-50% of free fatty acids (FFA), 40-60% of resin acids (RA), and 10-15% of unsaponifiables. It is generally produced at 20-30?kg tall oil/ton wood. The global production of CTO is approximately, 1.6 million metric tons per year, and in the U.S. alone, about two thirds of the FFA supplied to the chemical industry is derived from CTO. Generally, CTO is used for production of adhesives or thickening agents. Resolute Forest Products (RFP), a pulp and paper mill located in Thunder Bay, Ontario, is currently producing 20 t/day (7,000 t/year) of CTO. RFP stores CTO in storage tanks with capacities of 160 m3 until it is transported by rail cars in quantities of about 100,000 L. RFP is now interested in investigating the opportunity for on-site utilization of CTO that can diversify their product range and generate extra revenue. The products that can be potentially derived from CTO include biofuels (biodiesel, tall oil pitch fuel), and value-added bioproducts (fuel additives). Production of biofuels and fuel additives from CTO requires prior fractionation of CTO into free fatty acids (FFA), resin acids (RA), and residual unsaponifiable components (tall oil pitch fuel). The FFA and RA fractions will be used to produce biodiesel and fuel additives. This research project will be conducted in collaboration with the Biorefining Research Institute (BRI) at Lakehead University, Thunder Bay. The complete utilization of all three fractions of CTO for value-added products at RFP represents a waste-free technology that will generate extra energy and income for the mill. The proposed approach is novel and provides the mill with flexibility to switch on between biofuels and bioproducts depending on market conditions and price fluctuations. Anticipated techno-economic outcomes from the use of fuel additives include improved fuel consumption (by 10%), reduced smoke (by up to 50%), lower GHG emissions (by up to 25%), longer engine life, etc. These benefits will have a positive impact on Canada's environment and contribute to the effort of combating climate change and global warming.