Volume 5 biomass and biofuel production 5 19 – extracting additional value from biomass

Volume 5 biomass and biofuel production 5 19 – extracting additional value from biomass Volume 5 biomass and biofuel production 5 19 – extracting additional value from biomass Volume 5 biomass and biofuel production 5 19 – extracting additional value from biomass Volume 5 biomass and biofuel production 5 19 – extracting additional value from biomass Volume 5 biomass and biofuel production 5 19 – extracting additional value from biomass

5.19 Extracting Additional Value from Biomass MF Askew, Wolverhampton, UK © 2012 Elsevier Ltd All rights reserved 5.19.1 5.19.2 5.19.3 5.19.4 5.19.5 References Further Reading Introduction The Current Position Future Development – Background The Future: Extending the Envelope by Exploiting Higher Value Metabolites Conclusion 385 387 389 390 392 393 393 5.19.1 Introduction The concept of using biomass as a feedstock for a wide range of molecules has hardly been exploited at all in the land-based sector of agriculture and only marginally more so in the forestry sector However, for a number of reasons, it is clear that the same approach could be taken with surplus or processed biomass materials (including outputs from processed foods) as is taken with crude oil whereby a wide range of products are developed from that oil, and according to anecdote, about 80% of the incoming revenue stream is produced by approximately 20% of the fractionated crude oil Many years of experience and development have led to general agreement throughout the oil-refining industry that basic crude oil can be split into a small number of major components, and that they in turn can be processed to produce at least 12 other secondary chemical groupings, which in turn produce a wide range of intermediates including biofuels and additives for biofuels, and many nonfuel feedstocks The latter in turn are used to produce an even wider range of crude oil-derived finished products for the marketplace This process does pose the basic question as to what is the primary target output, that is, is the primary target of processing a fuel or an added-value product or a range of products and should the production of a fuel or biofuel be the driver for all decision making in the processing chain? In reality, the answer to this fundamental question is probably ‘no’, which in turn raises the question of rethinking of current processing in the biomass sector, particularly in the manufacture of first-generation biofuels such as rapeseed methyl ester or grain-derived bioethanol, if higher value coproducts are to be developed and marketed Hence the ‘traditional’ biorefining process may have energy as the final rather than the primary output (see Figure 1) The experience in land-based industry to date has been that coproducts, or rather vegetable wastes as they are called by many primary manufacturers, have been fed to livestock predominantly This has occurred in the production of sucrose from sugar beet where wet or dry extracted pulp has been fed directly to livestock or in the dry state incorporated into livestock rations, while stones and soil from the harvested crop have been marketed separately Some of the products produced from processing of the sugar beet and its extracted sucrose (e.g., factory lime) are sold as ameliorators for soils on-farm The sale of distillers grains (sometimes called draff) or brewers grains from the production of whisky or beer and pomace from the production of perry or cider has in reality been a way of finding a cheap feed for animals that would use up the ‘wastes’ from the primary food or industrial production in a way that does not involve significant investment or reprocessing of these so-called wastes This chapter in no way decries the exploitation of these materials but perhaps highlights the traditional linkages between agricultural produce and the utilization of coproducts from those primary feedstocks on-farm However, and conversely, in the production of cane sugar, the primary product has been sucrose while the waste has been bagasse, and this has until recently been used almost exclusively as a biomass feedstock for cane refineries, being used as a primary fuel for boilers With the advent of improved boiler systems and enhanced yields and factory throughput, these uses are declining and new uses for some bagasse are being sought In this way, opportunities to extract additional value products are emerging In forestry, the primary uses of wood have been as a structural material, a fuel, or a feedstock for paper pulp In the first two cases much of the primary material (e.g., leaves and small branches from trees) has not been exploited to the full extent However, in the case of paper pulp, then black liquor, for example, has been and is being developed further as a feedstock for further products Similarly, wood chips from knots and larger pieces of wood in the pulp mill have been used in the production of composites or elsewhere, and in the amenity horticulture sector bark these chips have become a major market So to develop further and maximize the economic potential of biomass, the biomass sector has to learn lessons from the crude oil industry and integrate the lessons with existing ways of utilizing ‘waste’ biomass while introducing additional novelty It has to be recognized that the key element in developing sustainable products is that there is no waste, only wasted opportunity, and that interestingly, many of the developments of new molecules from biomass not need new chemistry, but rather application of existing technologies to new scenarios Clearly, when sustainability is recognized as a three-component issue, being a function of economic cost, environmental cost, and acceptability and cultural/social factors, the potential benefits of development of additional molecules from an existing feedstock become self-evident Comprehensive Renewable Energy, Volume doi:10.1016/B978-0-08-087872-0.00525-4 385 386 Expanding the Envelope Primary biorefinary Primary product Primary separation Secondary biorefinery Product Intermediate Sec conversion Intermediate Product Secondary separation Conversion/pretreatment ‘Pretreatment’ Biomass Primary product Product Figure Schematic representation of biorefining Drawn by Prof J Sanders (2006) Some efforts have been made to identify pathways for total utilization of some crop plants, even though these are not fully operational at present, for instance in wheat, as an example of a major cereal, and in hemp (Cannabis sativa), as an example of a primary fiber-producing plant These are shown in Figures and Wheat (whole) Wheat (grain) Raw juice Acid phytic Mills Fermentation Hydrolysis Purification Straw Flours Brans Cosmetics Bran fibers Seperation Distillation Division Amidyne Acid hydrolysis Gluten Dietetics Vinasses Ethanol Alcoholic Extraction Purification Proteins Starch Division Chemical Proteins Lipids free Ceramides Enzymatic hydrolysis Dried distillers grains extraction Hydrolysis Modified starches Sugars neutral Lignocellulosic residues Glycosylation Extraction cellulose Glucose Peptides Surfactants Micro fibers Etoh/acid Anti oxidants Feedstocks Hyaluronic acid Cosmetics Veal feed Paper industry Biodegradables Fermentation Detergents Paper industry Thickenings Packaging Hyaluronic acid Cosmetics (Straw) (Brans) Cosmetics Nutrasweet Figure The potential to exploit metabolites of wheat (Triticum aestivum) Reproduced from IENICA website (http://www.ienica.net) Extracting Additional Value from Biomass High-value pharmaceuticals 387 Biomass for fuel Hemp Plant (Cannabis sativa) Stems Seeds -­ Bast fiber ­- ­ Shiv Oil Bait for coarse fishing Wild bird food - -High-value Paper bedding for horses Cardboards Filtration Composite boards Insulation Human consumption ‘Traditional’ technical uses of vegetable oils (paints and varnishes, solvents, lubricants) Personal care products (soaps, creams, lipstick) -Composites (e.g., car door linings, brake linings) Lower value textiles (ropes, strings, canvas/rigging carpet backing, sand bags) High-value textiles (clothing, uppers for shoes, upholstery or garment fabrics) Figure The potential to exploit different fractions and metabolites of hemp (Cannabis sativa) Hemp Fiber + Shiv + Seed Food + fishing + chemistry Paper + composites + textiles Animal bedding + composites Figure Diagrammatic representation of biofractionation Interestingly, the components of hemp are separated as physical entities rather than by chemical fractionation or separation So this process, physical fractionation, is fundamentally different though equally important as biorefining (Figure 4) 5.19.2 The Current Position Not surprisingly, the marketplace has been the primary driver for exploitation of many plant-based materials The exploitation has been based hitherto on the need for a primary product from that plant rather than the fully integrated exploitation of that plant’s potential However, research in EU15 and EU27 has confirmed massive markets for sustainable nonenergy bioproducts (IENICA, 2000 and 2003) Wheat remains as one of the world’s major crops (see Table 1) It is used both as animal feed and as a basis for bakery products, in particular in the human food sector In addition, some wheat starch has nonfood or nonfeed uses Yet the grain component of 388 Expanding the Envelope Table Production of mainstream cereal crops on a world basis Crop Harvest 2005 Harvest 2006 Harvest 2007 Wheat: area (in million hectares) Wheat: production (in million tonnes) Maize: area (in million hectares) Maize: production of grain (in million tonnes) Paddy rice: area (in million hectares) Paddy rice: production (in million tonnes) 220 627.7 147 713.9 155 634.5 212 605.1 148 706.3 156 641.1 214 606.0 158 788.1 156 657.4 Note: All data are rounded from more detailed FAO estimates Reproduced from FAOstat website wheat as expressed by its weight as a proportion of aboveground biomass (termed the harvest index) is approximately 50% Hence, a significant proportion of the wheat plant remains after harvest Traditional uses of wheat straw include thatching (specialty thatching wheat cultivars only), animal bedding, packaging for delicate items, and paper production Inevitably, a proportion of the wheat straw is not harvestable because of practical harvesting difficulties and a proportion must remain in the field and be reintroduced into the field soils to maintain soil nutrient status, friability, stability, and so forth Hence, only a proportion of the massive wheat straw tonnage is available for novel uses Biofuel, as second-generation bioethanol, has been suggested as one and clearly that technology is developing at an advanced rate However, thought should be given to the molecular components of wheat straw, rather than just targeting the lignocelluloses and associated celluloses present there Evidence has shown that winter wheat straw in the United Kingdom has the potential to supply a number of high-value products [1] Initial analyses of wheat straw in the United Kingdom by HTGC-MS (high-temperature gas chromatography-mass spectrometry) reported free fatty acids, fatty alcohols, alkanes, wax esters, sterols, and β-diketones The melting point of the wheat straw wax identified falls between that of animal-derived lanolin and currently available vegetable waxes, providing a potentially high added value but relatively low tonnage market for some wheat straw Further developments in extraction procedures have identified the potential for polycosanols, sterols, and long-chain odd-numbered alkanes, which could be extracted in a single-stage extraction process from wheat straw Clearly, high-value coproducts can be obtained from an erstwhile waste or at best low-grade biomass Other evidence suggests that silicon compounds could be extracted from wheat straw and that these would have uses in the water-processing industry However, the question arises as to whether these procedures to extract high-value molecules should perhaps precede those of bioethanol production from wheat straw And further, if lignocellulosics are to be a major feedstock for second-generation biofuels to replace gasoline, then thought needs to be given to the method by which lignin is removed from the lignocellulosic molecules and how value is added to it, rather than using it as a heating fuel as occurs frequently at present Early evidence from Sweden indicates the view held by many chemists that at least in terms of technology, lignin, a complex cyclic molecule, could form the basis for future aromatic chemistry [2] Oil rapeseed is the third major vegetable oil in the world after soy and palm oil, although its production does not reach anywhere near their levels (see Table 2) In Europe in particular rapeseed oil has become a key feedstock for the production of biodiesel, a first-generation biofuel The chemical processes involved are very straightforward and new uses for the large tonnage of low-grade glycerol formed as a coproduct are being examined However, there is growing evidence that rapeseed oil has significant beneficial effects on human health, especially when ingested as cold-pressed oil rapeseed Cold pressing should take place at not more than 40 °C The author’s own estimates suggest it to be the best vegetable oil in terms of human health, being on a par with extra virgin, cold-pressed olive oil, but potentially cheaper and in much greater supply In the manufacture of biodiesel from rapeseed at present, oil extraction begins with extrusion followed by hexane extraction of the residual oily meal The final residual hexane-extracted meal has a very low oil content and is fed to livestock as a proteinaceous Table Area and production of major oilseed crops on a world basis Crop Harvest 2005 Harvest 2006 Harvest 2007 Soybean: area (in million hectares) Soybean: production (in million tonnes) Oil palm (as oil palm fruit): area (in million hectares) Oil palm (as oil palm fruit): production (in million tonnes) Rapeseed: area (in million hectares) Rapeseed: production (in million tonnes) 92.5 214.3 12.9 95.2 218.4 13.2 90.1 219.5 13.9 181.9 195.0 192.6 27.7 50.0 27.4 48.0 29.7 51.4 Note: All data are rounded from more detailed FAO statistics Reproduced from FAOstat website Extracting Additional Value from Biomass 389 food, partially substituting for soybean meal Unfortunately, the processes used for current oilseed extraction are not at all conducive to the development of virgin cold-pressed oil rapeseed for human consumption or for the extraction of high-value molecules from the residual rapeseed meal Hence a number of questions arise, namely, is it prudent to use an oil with proven human health benefits primarily as a feedstock for a lower value biofuel to replace diesel oil? Also, if the development of cold-pressed oil rapeseed is to continue, and the marketplace in a number of European Union (EU) member states suggests it will, then current processing of bulk rapeseed may need to be revised and this in turn would lead to the potential to exploit more high-value molecules from the meal, such as albumins and associated feedstocks for adhesives [3, 4] and even plant or health protection products such as derivatives of glucosinolates While the first example cited above emanated from the extended use of wheat straw, its concepts could have enormous impact on the forestry and woodland biomass sectors and assist in their continued economic development especially in nontropical areas Evidence to support this view was confirmed in studies on 12 main tree species in the United Kingdom undertaken for UK Forestry Commission by Central Science Laboratory, York, UK (now FERA) [5] Fundamentally this study indicated that large numbers of molecules had been identified in the tree species concerned and that few had been extracted commercially While the current major broad-acre crops have been used as examples above, over time and especially because of climate change and the need to adapt cropping to environmental protection and avoidance of erosion, while trying to conserve water, grassland will become a major land user of the future on a worldwide scale Potential yield from grassland is not well exploited, with estimates suggesting only 33% of the yield potential being achieved [6] However, with improved technology and application to production, up to 50 million tonnes of grain currently being used as animal feed could be released for new uses (Riveros) This would offer excellent opportunities for industrial use and at the same time, the grassland itself, where not grazed (e.g., in areas suffering from seasonal inundation), would offer a feedstock for high-value metabolites as well as fibers for anaerobic digestion or biofuel use 5.19.3 Future Development – Background While the opportunities for exploiting high-value metabolites from plant materials are many, little progress has been made to date except in a few cases like starch production or the extraction of anticancer drugs from Californian yew First there is the issue of the marketplace itself and the use to which the primary biomass may be put As an example, in EU countries, Miscanthus species are grown, initially as a feedstock for heat or electricity generation However, from the growers’ perspective, these bulk uses are not the most profitable Evidence accrued informally by Turley showed that most alternative uses of Miscanthus provided a much higher return at the farm gate than did power generation (see Table 3) Hence the issue in this instance is not one of adding value to biomass for fuel, but substituting a more profitable market in toto Fortunately, this is an exception rather than a normal opportunity Nonetheless, other constraints to exploitation of secondary or high-value primary metabolites exist in industry and in the investor’s mind The IENICA project (2000) identified major markets for many plant products, yet few have been developed as already reported One key reason for lack of development has been that many primary products from land-based industry are bulky and relatively expensive to transport Furthermore, they occur in relatively small lots and, being biological products, have a degree of variability in terms of yield and composition Interestingly though, the IENICA project identified a number of nontechnical/scientific issues that contribute to slow development These included • • • • • lack of awareness of opportunities by both the general public and industrial users, a reluctance to change from proven processing technologies from other feedstocks, frequently nonsustainable feedstocks, concerns over the costs of retooling to utilize new feedstocks, concerns that investors would be exposed to higher risks than with proven technologies, and absence of any coherent or robust supply chain for much biomass Table An example of conflict between markets for one crop, Miscanthus Use Value a (£ sterling per tonne) Power generation Equine bedding Bagged equine bedding Organic straw Industrial use/composites 20–40 45–70 160–200 70 70 a Approximate values for different uses of the same crop Reproduced from Askew MF (2005) Quoting unpublished data from Turley In: McGilloway DA (ed.) Grassland: A Global Resource Wageningen Academic Publishers [7] 390 Expanding the Envelope Since the IENICA report was published, further concern has been expressed by investors over investment in the renewables sector in totality due to a perceived lack of coherence between different government policies and the fact that many polices have a relatively short life span, whereas investments have a significantly longer life span for repayment 5.19.4 The Future: Extending the Envelope by Exploiting Higher Value Metabolites While there is no one fundamental route to the identification and exploitation of higher value metabolites from biomass feedstocks, a number of options can be used to identify the most likely opportunities First there are several websites that give indications of occurrence of metabolites in plants These include, for example, Dr Duke’s Phytochemical and Ethnobotanical Databases (http://www.ars-grin.gov) or http://tree-chemicals.csl.gov.uk, the latter being a database produced from the work of Turley and others as quoted above However, it is important to recognize that these are not infallible and that previously unreported molecules can occur at significant levels in plant material, as reported by Hunt [8] in his studies on heather (Calluna vulgaris) and other associated Erica species Similarly, in many plant species, the occurrence of metabolites has been characterized at a particular time in the physiological life of the plant, most commonly at physiological maturity, and could therefore be different at other stages of the plant’s growth From a perspective of extraction procedures, the approach should be to develop a matrix of extraction procedures that exist in chemistry at present, including supercritical CO2 (as a useful way of removing high-value molecules without any environmental risk) against the groups of molecules of similar structure and activity as shown in concept in Table This shows what could be extracted in totality and by which extraction procedure Further elucidation of value and then market is needed Again a matrix approach can be used, with the values of the extracted metabolites being developed within the boxes in the matrix, by calculating the product of value per unit weight against its occurrence in the plant material and then calculating the gross value by market price of the molecule (see Table 5) From this gross income can be calculated the net return by deducting production and other costs to market However, it is crucial to note that many high-value molecules have relatively small markets in terms of tonnage and estimates of market must be made to ensure reality in development Where more than one molecular group will be extracted by a particular extraction process, a judgment may be needed about which is the more important molecule or, if more than one is to be exploited then additional separation and purification costs may be incurred Furthermore, decisions will need to be made as to which molecules to extract first from the energy-bound biomass, bearing in mind that the extraction procedures for one group of molecules may destroy or denature others On many occasions, the commercial exploitation of an extracted molecule may be limited by regulation This is especially so with pharmaceuticals The identification and likely activity of molecules can be predicted in many ways but full toxicity testing and assessment of long-term effects and side effects will be needed for registration of pharmaceuticals Undoubtedly, such testing is extremely expensive and unfortunately with many pure plant products the pharmaceutical so identified may not be able to be protected by patents or other intellectual property mechanisms although extraction procedures and purification techniques may be Hence investment may not necessarily be appropriate to develop such an opportunity In the case of the UK study on tree metabolites referred to above, the number of original papers identified in the study (>37 000) and the subsequent list of potential metabolites reported in them was immense A primary schematic approach to exploitation of molecules found in this study is shown in Figure Table feedstock Developing a matrix to identify extractives and extraction procedures from a given Molecular groups extracted Extraction Extraction Extraction Extraction Group A Group B Group C Group D Yes Yes No No No No Yes No Yes No No Yes Yes Yes Yes No Developing a simple matrix to identify highest gross return from Table various extractions of a particular feedstock Extraction method Extract Extract Molecular group A Molecular group B Molecular group C Molecular group D £X £Y £Z Extract £Q £P £K Extract £K £H £J Extracting Additional Value from Biomass 391 Tree (preliminary processing–separation into bark, etc., milling, grinding) Ultrasonic activation Cellulose Microwave/ alcohol/ supercritical fluid extraction Hemicellulose Supercritical fluid extraction Lignin Expanded cellulose Microwave heating (and/or ultasonic and environmentally friendly catalytic oxidation) Green chemical modification Modified expanded celusose Chemical products Green chemical modification Supercritical fluid fractionation Higher value chemical products Work proven To do/ongoing Porous (mesoporous?) carbons underlined Low environmental impact technologies Valuable products Figure Roadmap for extraction of metabolites from some tree species Reproduced from Turley DB, Chaudhry QM, Watkins RW, et al (2006) Chemical products from temperate forest tree species – Developing strategies for exploitation Industrial Crops and Products 24: 238–243 [9] As a consequence computer-aided quantitative structure–activity relationship modeling was used to assist in identifying likely modes of activity of molecules identified in the study Obviously this procedure creates a sound basis for selecting some high-value molecules from biomass and is already in use commercially in industry where selections are made to develop sweeteners, pharmaceuticals, catalysts, pesticides, and so on Some small-scale crops, for example herbs, produce a range of molecules or extracts that are well established in the marketplace Development, especially if cost is high, of replacements from new biomass is unlikely to be easy because of the conservative nature of that market and its buyers at wholesale and retail levels Also, the marketplace has already identified the link between the extract or essence with a particular plant and changing that perception is difficult to achieve Furthermore, care is needed in selecting the correct chemotype, where otherwise morphologically identical plants within one variety have differing chemical constitutions (as opposed to plant species and variety being wholly genetically and phenotypically identical), and in harvesting, where time of harvesting can affect the metabolites present in the plant A further method for developing biomass-derived options to replace fossil oil applications has been developed by Sanders in the Netherlands (informal discussions in the BECOTEPS Workshop, Brussels, 2009 [2]) In this instance, the approach has been to apply the biomass-derived molecule to replace an existing intermediate in a chemical process and also reduce the number of steps in that process In both instances, such an approach should lead to enhanced opportunities for sustainability 392 Expanding the Envelope Figure High-value fashion items from cellulose obtained from the beech tree High-value molecules are not necessarily uncommon molecules; for example, cellulose is a very common molecule and is used as a bulk feedstock in papermaking However, at the same time, very high-value materials can be prepared from cellulose from hardwood-based feedstocks, for example, beech (Fagus sylvatica) or Eucalyptus species, which is converted into a fine fabric for garments by an Austrian company in Vienna (see Figure 6) 5.19.5 Conclusion Clearly there are a multitude of uses to which the various components of biomass can be put to They may vary according to the composition of the plant, which in itself will be modified by physiological age, climate/G � E (genotype by environment) interaction, and other issues If the challenge is to add value to biomass initially intended for biofuel production, then clearly the longer term biofuels need to be identified While there are no firm guidelines in this instance, it is fair to presume that the use of first-generation biofuels as biodiesel (a methyl ester) or as a grain-derived bioethanol is not likely to continue in the long term Second-generation biofuels, especially using bulk lignocellulosic feedstocks, will develop further but it seems that economics and issues of sustainability will together form a basis for moving to the biorefining of biomass, a process whereby chemistry meets land-based industry and optimizes the output from a particular biomass In this scenario, the need is for the components of the biomass to be known and the optimal extraction procedures for their extraction and later commercialization to be developed This approach has the advantage of being versatile in that should biomass for fuel cease to be an imperative or a policy target, the biorefining process would stand alone substantively and supply ‘the other markets’ With respect to biofuel policy, it is interesting to note the change in emphasis that has occurred in the past years where the focus has moved to renewable fuels as opposed to biorenewable fuels and in this instance hydrogen-fueled vehicles and electric vehicles are now coming into vogue The likely impact of this change may be to throw the emphasis back onto developing and exploiting the most valuable molecules found in biomass but not necessarily biomass for fuel [10] Extracting Additional Value from Biomass 393 References [1] Deswarte FEI (2006) Extraction of High Value Molecules from Wheat Straw (Triticum aestivum) PhD Thesis, University of York [2] BECOTEPS (2009) Individual comments made by experts in a non-food products workshop organised under the framework of the BECOTEPS project (The Bio-Economy ETPs EU project) To be formally published in the future, as a formal White Paper [3] Atterby H, Larre C, Chaudhry QM, et al (2003) Isolation and characterisation of certain bioactive proteins from de-oiled rapeseed meal In: Sorensen H (ed.) Proceedings of the 11th International Rapeseed Congress ‘Towards Enhanced Value of Cruciferous Oilseed Crops by Optimal Production and Use of the High Quality Seed Components’ 6–10 July Copenhagen, Denmark: The Royal Veterinary and Agricultural University [4] Malabat C, Atterby H, Chaudhry Q, et al (2003) Genetic variability of rapeseed protein composition In: Sorensen H (ed.) Proceedings of the 11th International Rapeseed Congress, pp 205–208 6–10 July Copenhagen, Denmark: The Royal Veterinary and Agricultural University [5] Watkins RW and Turley DB (2003) A review of current knowledge on the economic potential of chemical products from main commercial tree species in U.K Report for UK Forestry Commission and Government Industry Forum for Industrial Crop Applications, 256pp http://tree-chemicals.csl.gov.uk [6] Riveros F (undated) FAO Grassland Group Document http://www.fao.org/ag/AGP/AGPC/doc/PUBLICAT/GRASSLAND/3.pdf [7] Askew MF (2005) Quoting unpublished data from Turley In: McGilloway DA (ed.) Grassland: A Global Resource, pp 179–189 Wageningen, The Netherlands: Wageningen Academic Publishers [8] Hunt AJ (2006) The Extraction of High Value Chemicals from Heather (Calluna vulgaris) PhD Thesis, University of York [9] Turley DB, Chaudhry QM, Watkins RW, et al (2006) Chemical products from temperate forest tree species – Developing strategies for exploitation Industrial Crops and Products 24: 238–243 [10] Enhance The enhance project funded under EU funding as project QLRT-1999-01442 Enhance: Green chemicals and biopolymers from rapeseed meal with enhanced end-performances http://www.biomatnet.org/secure/FP5/S1186.htm Further Reading [1] [2] [3] [4] [5] [6] [7] [8] [9] Brown RC (undated) The Future of Biorefining Biomass, 13pp USA: Iowa State University Carvalheiro F, Duarte LC, and Girio FM (2008) Hemicellulose biorefineries: A review on biomass pretreatments Journal of Scientific and Industrial Research 67: 849–864 De Jong E (undated) Task 42 biorefineries Co-production of fuels, chemicals, power and materials from biomass An occasional paper published by IEA Bioenergy den Uil H, Mozzafarian H, van Ree R, et al (undated) High efficiency biorefinery concepts An occasional publication on behalf of the European Commission by the Partners of Bioenergy Network of Excellence Domsjo Biorefinery (undated) Occasional paper produced by the Domsjo Biorefinery Sweden Epobio Reports from the EPOBIO project funded under Framework Programme of EU funding Project SSPE-CT-2005-022681 European Commission, Brussels (2006) European Conference on Biorefining Helsinki, Finland http://ec.europa.eu/research/energy/gp/gp_events/biorefining/article_3764_en.htm Jungmeier G, Lingitz A, and Spitzer J (undated) Biofuel production from wood Feasibility study for a biorefinery in the Austrian province of Styria Informal paper published on behalf of European Commission by Joanneum Research, Graz, Austria Sanders J, Scott E, and Mooilbrock H (undated) Biorefinery, the bridge between agriculture and chemistry, 5pp An occasional paper from the Department of Valorisation of Plant Production Chains, Wageningen University and Research Centre, Wageningen, The Netherlands Relevant Website http://www.biomatnet.org – Database of projects funded under various European Commission R&D programmes  ... hectares) Rapeseed: production (in million tonnes) 92 .5 214.3 12.9 95. 2 218.4 13.2 90.1 219 .5 13.9 181.9 1 95. 0 192 .6 27.7 50 .0 27.4 48.0 29.7 51 .4 Note: All data are rounded from more detailed... use/composites 2 0–4 0 45 70 16 0–2 00 70 70 a Approximate values for different uses of the same crop Reproduced from Askew MF (20 05) Quoting unpublished data from Turley In: McGilloway DA (ed.) Grassland: A... molecules found in biomass but not necessarily biomass for fuel [10] Extracting Additional Value from Biomass 393 References [1] Deswarte FEI (2006) Extraction of High Value Molecules from Wheat Straw