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T109 product development Biorefinery opportunities for the Canadian pulp and paper industry By M. Towers, T. Browne, R. Kerekes, J. Paris and H. Tran A b s t r a c t : The Canadian pulp and paper industry must identify new value-added products in order to compete. One potential pathway is the forest biorefinery. This paper reviews feedstock availability, novel products easily produced in existing facilities, and existing or emerging technologies. Feedstocks include hemicellulose, lignin, volatile organic compounds, organics in wastewaters, wood resins, and sawmill and forestry residuals. Products include transportation fuels, commodity chemicals, chemical building blocks, specialty chemicals, biopolymers, and other novel products. Technologies include chemical, thermochemical and biochemical processes for products such as bioethanol. REFINERY EXTRACTS, isolates or modifies components of a feedstock to produce one or several useful products. The “biorefinery” is a refinery utilizing biomass as a feedstock to produce gaseous and liquid fuels, specialty or commodity chemicals, or other products commonly produced in petrochemical refineries, where the feedstocks are mainly fossil fuels. While there are similarities between the biorefinery and the petroleum refinery, there are also important differences [1]. For example, biobased chemicals have more oxygen, making production of certain organic products easier. Separation processes will be as critical for the biorefinery as they are for the petroleum refinery; A M. TOWERS Pulp and Paper Research Institute of Canada Prince George, BC T. BROWNE Pulp and Paper Research Institute of Canada Pointe-Claire, QC however, since bio-based chemicals are less volatile, it is likely that distillation will be only one of many separation methods used. Advances in genetics, biotechnology, process chemistry and engineering are leading to new methods for converting renewable biomass to fuels and chemicals. There has been much interest recently in the concept of the forest biorefinery from the research community, the forest industry, and policy makers [1-5]. The concept is attractive because it can help address current concerns around oil prices, finite fossil resources, and Kyoto commitments. Biomass rich nations see an opportunity to utilize their natural bio-resources in new ways to achieve maximum value and productivity within the confines of sustainability. In Canada, the pulp and paper industry is a major employer and contributor to the economy. Recently, higher energy costs, currency appreciation, declining newsprint use, and lower manufacturing costs at newer market pulp facilities in the tropics, have resulted in a difficult economic environment for Canadian companies [6]. This adds urgency to the need to revitalize the industry; adopting biorefinery concepts is one path forward [7-10]. Three critical factors must be examined to assess the potential for a biorefinery in a given context: feedstocks, conversion and separation technologies, and markets for products. The number of possible concepts is large, but preferred routes begin to emerge by examining each segment of the biorefinery. FEEDSTOCKS R. KEREKES Chemical Engineering Department University of British Columbia Vancouver, BC J. PARIS Chemical Engineering Department École Polytechnique Montreal, QC 26 • 108:6 (2007) • PULP & PAPER CANADA H. TRAN Chemical Engineering Department University of Toronto Toronto, ON The products generated in a biorefinery will primarily be a function of the feedstocks available. Feedstock properties, such as cost, location, composition, moisture content and availability, will dictate the appropriate technical options; feedstock costs can represent a large portion of plant operating costs. One approach is to locate the biorefinery near the feedstock to reduce or eliminate transportation costs. If the feedstock is a waste stream from an existing process, disposal or treatment costs may be offset, resulting in a near zero feedstock cost. From this perspective, the most attractive feedstocks would be those that inhabit the lower left quadrant of the diagram in Fig. 1. About half the organic mass that enters a kraft pulping line is incinerated. Capturing more useful energy from this organic mass is a key aspect of mill energy efficiency programs. Boiler temperatures and pressures have risen over time to increase power production in steam turbines. However, conventional cogeneration does not represent the ceiling of usefulness for these feedstocks; rather, it represents the floor. All kraft mills in Canada operate a wood waste boiler in addition to their recovery boiler. Most require this additional steam to operate their process, but there is significant opportunity to improve process energy efficiency to eliminate any fossil fuel used to generate steam and to liberate feedstocks for biorefinery opportunities. In addition to available on-site feedstocks, conventional forestry practices leave residuals on the forest floor (branches, foliage and tree tops). These represent 15 to 20% of the tree mass above the root, and are generally not utilized. In some countries, residuals are collected and used as fuel for large combined heat and power plants; tax incentives meant to reduce fossil fuel use in response to Kyoto have been a driving force behind these practices. Canada’s wealth of natural resources and cheap hydroelectric power have been the main barriers to implementing similar practices. This is changing, however, as demand in regions normally in surplus of hydroelectric power is growing beyond the installed capacity, leading to increased reliance on high cost incremental capacity. Pulp and paper mills are typically the largest industrial infrastructure located near forestry residuals. Even so, transportation to the mill site has been highlighted as an obstacle to utilizing this material. Mobile energy densification technologies, such as truck-based pyrolysis units, to concentrate these residuals for transport to a utilization site have been proposed. At least one initiative demonstrating this approach is underway in Canada [11]. In some selected instances it may also be attractive to utilize non-forestry biomass waste. Agricultural residuals or even energy crops may provide interesting opportunities [12]. TECHNOLOGIES Most technologies for converting biomass into products are in need of significant development to meet techno-economic criteria required for investment. Some of the key issues are development status, capital cost, operating and maintenance cost, product yield, current scale of the process, infrastructure needs, by-products and wastes. Pulp and paper mills offer access to infrastructure such as steam, rail Interesting Feedstock Material Cost peer-reviewd Internally available biomass currently under-utilized Regionally available biomass currently under-utilized Internally available biomass currently considered a waste Regionally available biomass currently considered a waste Increasing Feedstock Transportation Cost FIG. 1. Feedstocks value chart. transportation, chemical handling, effluent treatment and other utilities, and may be able to utilize by-products or wastes from technologies implemented on-site, thereby raising the overall biomass utilization efficiency. Such integration opportunities could make biorefinery concepts economical earlier or on a smaller scale than with stand-alone biorefinery. Technology options generally fall into one of the categories in Table I. Separation technologies would be utilized when the target product of interest is already present in the mill. An example would be methanol in contaminated condensates. Distillation is used to bring its concentration to 90%, but its end use is usually as fuel for heat. Further purification and even transformation is possible to make better use of this green methanol source. Gasification of fossil fuels is done commercially on very large scales [13]. Gasification of biomass is not done on such a large scale and the gas product is currently used only for heat applications. There are several initiatives underway to produce synthesis products from syngas derived from biomass feedstocks such as pulp mill black liquor [14, 15], wood residues [16], and pyrolysis oil [17]. But gas cleanup, gas composition, and process economics are critical barriers to commercial adoption, in particular for black liquor. Pyrolysis has mainly been suggested as an energy densification technology in order to reduce the transportation costs of forestry residuals. Pyrolysis oil produced by mobile or regional plants could be fired in gasification plants located at pulp and paper mills. Hydrolysis of sugars from hemicellulose and cellulose has been in development for many years. Commercial operation at a Canadian sulfite mill today is evidence of the possible integration of this approach with pulp and paper operations. Partial extraction of hemicellulose from wood chips prior to pulping has been suggested as an option for kraft mills. Non-traditional conversion routes will be required, as hemicellulose is comprised of a significant amount of pentose sugars, such as xylose, which are not as readily fermented as hexose sugars. Hemicellulose extraction may result in reduced thermal load going to the recovery boiler, which in turn may entail added costs to either reduce steam use in the mill or increase steam production from other boilers on-site; this may be offset to some degree by reduced chemical consumption and causticizing requirements. PRODUCTS Specialty and commodity chemicals Twelve building block chemicals that can be derived from biomass sugar platforms have been identified by the US Department of Energy [18]. Many of these are presently made from high-cost natural gas. A study commissioned by Industry Canada [19] predicted North American markets for a number of high-growth chemical intermediates, several of them not listed in the DOE report, in 2020. Polylactic acid, whose production is expected to grow by 19% per year to 640,000 metric tonnes by 2020, is presently produced by Cargill as a biodegradable bio-plastic. Prices are still relatively high, limiting demand; as production increases, prices are likely to drop and demand increase. Citric acid, predicted to grow by 3% per year to 450,000 metric tonnes by 2020, is used in food and beverages, and capacity appears well matched to the demand at the present time. Growth for propylene glycol is expected to be 4% per year, reaching 1.3 million tonnes; competition from lower-priced chemicals may PULP & PAPER CANADA • 108:6 (2007) • 27 T110 T111 product development make this a difficult market to enter. Sorbitol is expected to grow by 3% per year to 400,000 tonnes; new capacity would have to compete with existing capacity, which appears to be adequate for the market. Formaldehyde growth, at 3%, is expected to lead to a market of 7.5 million tonnes. Existing capacity is adequate, but demand is growing in Asia. Finally, 1,4-butanediol, with a 4% growth rate, is expected to grow to 860,000 tonnes. Clearly, more detailed market analysis is needed to fully evaluate these and other opportunities. Transportation fuels While some chemical markets may be small, high-value markets with wellentrenched traditional suppliers, transportation fuels represent a large market with no threat of market dilution from biomass sources, even if it were conducted on a scale as large as the entire pulp and paper industry. Ethanol, methanol, butanol, dimethyl ether, biodiesel, Fischer-Tropsch products and hydrogen are among the possibilities. Ethanol can be produced from sugar platform technologies as well as via gasification and synthesis routes. Other transportation fuels are possible primarily through the gasification and synthesis route. In part for political reasons, ethanol seems set to serve as a supplement to stretch gasoline supplies. Oil prices, which are a strong function of supply and demand, as well as unforeseen weather or geopolitical events, will be a key risk factor in entering the ethanol business. Low oil prices make ethanol uneconomic in the absence of government intervention; the loss of such support is another key risk factor if oil prices are low. One analyst has pegged the price of oil at which corn ethanol becomes economic in the absence of government intervention at $US50 per barrel [20]. The US Energy Information Agency predicts oil prices will remain in the range $US50 to $US60 per barrel for the next two decades [21], leaving little room for profit. A second key risk factor will be the response of the Brazilian industry to an increase in world prices. While exports to the US are currently limited by tariffs, Brazil exports large amounts to Japan and the EU and can have an impact on world supply and prices. Finally, government action in many countries will drive the market in unpredictable ways. The US government is pushing ethanol production for political and strategic reasons; other countries have Kyoto implementation plans which rely, to a certain degree, on replacing gasoline with ethanol. Changes in these subsidy patterns as governments change is a risk factor to be considered. The availability of subsidies to US producers also makes it more difficult for Canadian pro- 28 • 108:6 (2007) • PULP & PAPER CANADA TABLE I. Main technology options. Separation Thermochemical Chemical and Biological Distillation Gasification Hemicellulose extraction & conversion Membrane Pyrolysis Cellulose hydrolysis & conversion Filtration Hydrothermal Esterification of tall oil and fatty acids Solvent extraction Resin exchange ducers to compete in the US market. Overall, many nations are moving to ethanol production or imports as a means of mitigating oil prices or of meeting Kyoto commitments. While the production of ethanol seems set to grow, the world demand is likely to grow as well. Government support in many countries appears strong, at least for the short term, mitigating the poor economics when compared with petroleum. Providing Solutions: The Canadian Forest Biorefinery Network The Canadian Forest Innovation Council (CFIC) recently sponsored a series of White Papers on transformative technologies for the forest industry. Three of the four papers dealt directly or peripherally with the concept of the biorefinery [2224]. The Canadian Forest Biorefinery Network has been proposed by Paprican and PAPIER to link research institutes and universities with mill and corporate staff in industry, in order to address the challenges laid out in these papers. PAPIER, the Canadian Pulp and Paper Network for Innovation in Education and Research, is an organization of Canadian university researchers active in the field of pulp and paper. The network will focus on the key objective of identifying novel processes and products which can be produced from forest-based feedstocks, initially by existing pulp mills, and later by standalone bio-refineries. While the emphasis will be on forest feedstocks, including the development of systems for harvesting and delivering biomass to a conversion site, the potential to use agricultural feedstocks in existing pulp mills will also be investigated. The activities will range from stationary combustion through transportation fuels and specialty chemicals to chemical building blocks and precursors for plastics and other materials. A program of this scale will require significant collaboration and investment from the chemical and energy industries, as they understand the grade structures and end-uses, business cases and economics, market size and product purity requirements of markets which are new to the pulp and paper sector. Partnership with these industries will be an essential component of a successful network. Anaerobic digestion Twelve broad themes, or program outlines, have been developed to address the barriers identified in the CFIC White Papers. These themes are described in Table II. Each theme is meant to stand alone, but there will need to be significant interaction between researchers and developers active in different areas, hence the network concept. CONCLUSIONS The Canadian pulp and paper industry is in need of a new business model. The identification of new products to replace existing commodity products offers one avenue for transforming the industry. The biorefinery provides a pathway to new products, and offers the potential to increase revenues through better utilization of existing on-site biomass, as well as the development of new, non-traditional biomass sources. Pulp and paper mills are logical hubs of biorefinery activity. They have on-site feedstocks, are located within active forestry regions, and have the infrastructure required by potential biorefinery plants. They can provide utilities, utilize waste streams, and treat effluents. Many technologies and products are possible, but ultimately the nature of the feedstocks and value of products will drive the technical development of the biorefinery. The majority of the potential pathways described here focus on the production of transportation fuels and other substitutes for petroleum-derived products. Much remains to be done. In response to a request from industry and government leaders, Paprican and PAPIER have prepared a proposal for a Canadian Forest Biorefinery Network. The network goal is to ensure the necessary research, development and demonstration work is done in a collaborative fashion, with minimal overlap and maximum efficiency. ACKNOWLEDGEMENTS The support of Industry Canada, the Canadian Forest Innovation Council and the Alberta Research Council for this work is gratefully acknowledged. The PAPIER-Paprican Biorefinery Task Force prepared the Canadian Forest Biorefinery Network proposal, from which portions were extracted for use here. The support 22661_26-29 7/9/07 9:48 PM Page 29 peer-reviewd from PAPIER’s Council of Directors is also recognized. L I T E R AT U R E 1. RAGAUSKAS, A.J. et al., The path forward for biofuels and biomaterials. Science 311(1):484-489 (2006). 2. MAGDZINSKI, L. Bioenergy and bioproducts at Tembec: synergies in integrated processing of biomaterials. PAPTAC 92nd Annual Meeting, Montreal (2006). 3. REALFF, M.J, ABBAS, C. Industrial symbiosis: refining the biorefinery. Journal of Industrial Ecology 7(34):5-9 (2004). 4. CUNNINGHAM, J.E. Biomass as an industrial feedstock. Canadian Chemical News 24-26 June (2005). 5. BUSH, G.W., State of the Union Address, January 31 (2006). 6. Price Waterhouse Coopers, The Forest Industry in Canada: (2003). 7. IPILÄ, K., MCKEOUGH, P, MÄKINEN, T. The pulp and paper industry can offer new innovative bioenergy platforms. PulPaper 2004, Helsinki (2004). 8. THORP, B. Biorefinery offers industry leaders business model for major change. Pulp & Paper 79(11):3539 (2005). 9. VAN HEININGEN, A. Converting a kraft pulp mill into an integrated forest products biorefinery. PAPTAC 92nd Annual Meeting, C167-C176, February 2006, Montreal.(2006). 10. AXEGARD, P. The pulp mill biorefinery. 1st International Biorefinery Workshop, Washington D.C. (2005). 11. BADGER, P.C., FRANSHAM, P. Use of mobile fast pyrolysis plants to densify biomass and reduce biomass handling costs — A preliminary assessment. Biomass and Bioenergy, In press (2006). 12. ROOKS, A. A Sweet Future for Bio-Fuels?. Solutions!, Vol. 89(2): (2006). 13. PHILLIPS, G. Gasification — A versatile solution for clean power, fuels & petrochemicals & an opportunity to reduce CO2 emissions. 7th World Congress of Chemical Engineering, Glasgow (2005). 14. EKBOM, T. et al. Technical and economic feasibility study of black liquor gasification with methanol/DME production as motor fuels for automotive uses — BLGMF, Final report of Concerted Action with EU Altener Program, Nykomb Synergetics AB, Stockholm (2003). 15. O’BRIAN, J. New alternative to conventional spent liquor recovery. PaperAge 113(2):18-19, 22 (1997). 16. BLADES, T., RUDLOFF, M., SCHULZE, O. Sustainable SunFuel from CHOREN’s Carbo-V process. International Symposium on Alcohol Fuels XV, September 2005, San Diego. 17. HENRICH, E. Fast pyrolysis of biomass with a twin screw reactor — a first BTL step. PyNe Newsletter 17:67 (2004). 18. WERPY, T., PETERSEN, G. Top value added chemicals from biomass — Volume I: Results of screening for potential candidates from sugars and synthesis gas, U.S. Department of Energy (2004). 19. Industry Canada, Towards a technology roadmap for Canadian forest biorefineries, report in preparation (2007). 20. RIESE, J. Industrial Biotechnology: Turning Potential into Profits. Third Annual World Congress TABLE II. Proposed research activities. Title Description Product opportunity analysis Availability of forest feedstocks Market analysis; high value vs. high volume products Available biomass (forest, sawmill, pulp mill, agricultural or other residues): costs, logistics, etc. Thermochemical pathways Gasification and pyrolysis pathways to novel products Bioproducts from Bio-degradable plastics; products from anaerobic treatment effluent and solid wastes systems; value-added uses of sludges Products from hemicellulose Extract fuels and specialty chemicals while maintaining pulp properties Products from lignin Extraction of lignin from kraft black liquor, and its use in novel products Products from extractives Synthetic diesel and other products from crude tall oil Products from condensates Methanol extraction, purification, and transformation processes Phytochemicals Novel high value, low volume products from bark, branches and foliage Integrating novel products Maintaining pulp and paper properties while modifying with existing product lines existing mills for novel products Conversion of uncompetitive mills Identify new uses for idled kraft production lines, in particular batch pulping systems Integration with other industries Identify synergies with commercial, industrial or domestic neighbours on Industrial Biotechnology and Bioprocessing, Toronto, 11-14 July (2006). 21. US Energy Information Agengy. http://www.eia.doe.gov/oiaf/aeo/pdf/aeotab_12.pdf , viewed 29 June (2006). 22. MABEE, W. Transformative technologies for the forest sector: Bioenergy production in Canada, CFIC White Paper, March (2006). 23. GARNER, A., KEREKES, R. Transformative technologies for Biochemicals, CFIC White Paper, March (2006). 24. KEREKES, R., GARNER, A. Transformative Technologies for Pulp and paper, CFIC White Paper, March (2006). R é s u m é : Pour demeurer concurrentielle, l’industrie canadienne des pâtes et papiers doit viser à mettre en marché de nouveaux produits à valeur ajoutée. De là le terme de bioraffinerie, par analogie avec la raffinerie de pétrole. La présente communication examine les points essentiels des stratégies de bioraffinage, notamment les matières premières accessibles aux usines canadiennes, les produits pouvant être extraits ou traités dans les installations existantes, et les technologies de bioraffinage disponibles ou en cours de développement. Les matières premières en cours d’évaluation comprennent l’hémicellulose, la lignine, les composés organiques volatils, les matières organiques des eaux usées, et les résidus des scieries et des forêts. Les produits possibles du bioraffinage englobent aussi les carburants pour le transport, les produits chimiques courants, les éléments constitutifs chimiques, les biopolymères, et les produits nouveaux potentiels. Les technologies de bioraffinage comprennent l’extraction d’éléments du bois et les procédés de transformation chimiques, thermochimiques et biochimiques pour la fabrication de produits comme le bioéthanol. R e f e r e n c e : TOWERS, M., BROWNE, T., KEREKES, R., PARIS, J., TRAN, H. Biorefinery opportunities for the Canadian pulp and paper industry. Pulp & Paper Canada 108(6):T109-112. (June 2007) Paper presented at the 93rd Annual Meeting in Montreal, QC, February 5-9, 2007. Not to be reproduced without permission of PAPTAC. Manuscript received December 13, 2006. Revised manuscript approved for publication by the Review Panel December 13, 2006. K e y w o r d s : CANADA, FOREST PRODUCTS INDUSTRY, BIOMASS, CONVERSION, FUELS, CHEMICALS, ECONOMICS, PRODUCT DEVELOPMENT, VALUE ADDED PRODUCTS. PULP & PAPER CANADA • 108:6 (2007) • CYAN MAGENTA YELLOW BLACK Business Info 22661 29 T112