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Bioethanol – status report on Lignocellulosic is seen as an attractive bioethanol production from feedstock for , particularly . and other lignocellulosic feedstocks Lignocellulosic feedstocks include agricultural residues, wood, municipal solid waste and dedicated CHRIS SCOTT-KERR3, TONY JOHNSON1, energy crops which have significant advantages over BARBARA JOHNSON2, JUKKA KIVIAHO4 first generation feedstocks for ethanol production. The net energy balance of lignocellulosic ethanol, in terms 1 General Manager – Forest Industries NZ, Beca of energy in/energy out, has been shown to be AMEC, P.O. Box 903, Tauranga, New Zealand significantly lower than ethanol produced from 2 Snr Process Engineer, Beca AMEC, P.O. Box 903, and starch feedstocks (2). Additionally, life- Tauranga, New Zealand cycle emissions of green house gases are reported to be 3 Snr Consultant, Forest Industries Consulting Group, 50-85% lower for lignocellulosic ethanol than those AMEC Americas Ltd, Vancouver, Canada from gasoline, with corn ethanol providing a 25-40% 4 Director of Projects & Technology, AMEC, Jose reduction (2,3). Lignocellulosic ethanol presents a Domingo Canas 2640, Nunoa-Santiago, Chile means of satisfying demand for ethanol without further pressuring food supply. Marginal land, not suitable for ABSTRACT food crops can be used, with less intensive use of water Lignocellulosic biomass is seen as an attractive and fertilisers. Production of can feedstock for future supplies of renewable fuels, also utilise ‘waste materials’ such as and reducing the dependence on imported petroleum. forest residues as feedstocks. However, there are technical and economic impediments to the development of commercial TECHNOLOGIES processes that utilise biomass feedstocks for the Lignocellulosic biomass can be converted to ethanol production of liquid fuels such as ethanol. Significant using either a biochemical or thermochemical platform. investment into research, pilot and demonstration plants is on-going to develop commercially viable Biochemical conversion processes utilising the biochemical and thermochemical In biochemical conversion the plant fibre is separated conversion technologies for ethanol. This paper into its component parts; , , and reviews the current status of commercial lignocellulosic hence the term lignocellulosic or cellulosic ethanol production and identifies global production ethanol. The cellulose is then further broken down to facilities. simple sugars that are fermented to produce ethanol. Typically the process is carried out in 4 stages (Fig. 1): INTRODUCTION 1. Physical or chemical pretreatment of the plant Escalating petroleum prices, green house gas emissions fibres to expose the cellulose and reduce its and the threat to fuel security are strong drivers in the crystallinity, search for sustainable fuel alternatives. 2. Hydrolysis of the cellulose polymer, with enzymes Governments around the world have recognised the or acids, to simple sugars (glucose), role that will play in a renewable fuels 3. Microbial fermentation of these simple sugars to portfolio and have introduced minimum targets for ethanol, and their implementation in the future (1). 4. Distillation and dehydration to produce 99.5% pure alcohol.

Fig. 1 Schematic of a biochemical cellulosic ethanol production process (4). Lignin is a byproduct of this process, and can be used Many pretreatments are currently being explored, as a boiler fuel or processed into specialty chemicals. ranging in chemistries from very acidic to mildly Hydrolysis and fermentation can be conducted alkaline, such as dilute acid, ammonia fibre expansion simultaneously in one stage but simultaneous (AFEX), wet oxidation, solvent based pulping (i.e. saccharification and fermentation (SSF) is yet to be organosolv) and steam explosion. The ideal implemented commercially, significant advances are pretreatment liberates , exposes the being made in this area. cellulose and allows the lignin to be separated and must also minimise the formation of degradation products Thermochemical conversion that can inhibit the subsequent hydrolysis and Thermochemical conversion transforms the fermentation processes. lignocellulosic feedstock into carbon monoxide and hydrogen (syngas) by partial combustion (Fig. 2). Lignin – As lignin is mainly responsible for These gases can be converted to liquid transportation lignocellulosic recalcitrance, particularly in softwoods, fuels or commodity chemicals by catalytic or biological studies have shown its separation during pretreatment pathways. The biological process converts carbon greatly enhances cellulose accessibility and enzyme monoxide to ethanol using a non- fermentation effectiveness (6). Pretreatments that minimise lignin microorganism (eg. Clostridium ljungdahlii). redeposition and condensation on the fibre surfaces are Alternatively, the syngas can be fed to a catalytic favoured. Separation of lignin and production of reactor where the carbon monoxide and water are specialty lignin co-products also has the potential to combined via a metal-catalysed process to produce improve the overall economics. methanol, ethanol, other higher alcohols or liquid fuels (Fischer-Tropsch liquids). Gasification is important Hemicellulose –Is composed primarily of 5 carbon because lignin, which constitutes about 25 – 30% of sugars, these may be liberated during the pre-treatment cellulosic biomass, is also converted to syngas and process or require further treatment with hemi-cellulase subsequently converted to fuel. enzymes. The C5 sugars may be fermented to ethanol or sold as a co-product. CURRENT STATE OF TECHNOLOGIES AND TECHNICAL CHALLENGES Hydrolysis - Cellulose is broken down into individual glucose units by cellulase enzymes, under mild Biochemical conditions. Research is on-going to find reduce the Pretreatment - the usefulness of cellulose as a costs of enzyme systems that produce high sugar yields feedstock has been limited by its rigid structure and at accelerated rates and without the formation of difficulty to breakdown into simple sugars. Cost- inhibitory byproducts. Currently, the per unit cost of effective pretreatments are needed to liberate the enzymes is considered to be a deterrent to the cellulose from the lignin/hemicellulose matrix and commercial success of the biochemical pathway. reduce its crystallinity. Pretreatments of increasing Alternative strategies to reduce enzyme cost include the severity are needed as feedstock recalcitrance increases recycling of enzymes and the use of polymers to reduce from nonwoods (agricultural residues) to hardwoods to the binding of enzymes to the substrate (7). softwoods.

Fig. 2 Schematic of a thermochemical cellulosic ethanol production process (5). risk. Many starch-based ethanol producers are Fermentation - The hydrolysate contains both 5-carbon currently struggling to survive and many may go (pentose) and 6-carbon (hexose) sugars. The bankrupt due to the volatile swings in corn, , conversion of pentose sugars into ethanol is less sugar and ethanol prices. efficient than conversion of hexose sugars. A system of mixed-sugar fermenting microorganisms is required A recent study of the production of Fischer-Tropsch to utilise the full range of sugars present and thus (FT) liquids from syngas has shown the maximise the production of ethanol. Metabolic thermochemical platform to be economically engineering is on-going to find low-cost, comparable to the biochemical platforms (8). microorganisms capable of C5 and C6 sugar co- fermentation that are also resistant to inhibitors (acetic CELLULOSIC ETHANOL PLANTS acid, ) that may be present. This section provides brief details on all publically announced bioethanol plants based on lignocellulosic Thermochemical feedstocks. The authors have endeavoured to be Contamination – various components of the biomass comprehensive but do not guarantee all facilities are feedstock can cause problems in the gasification and included. Table 1 summarises all known facilities as of catalytic synthesis stages. Contaminants such as tars February 2009, and these are shown geographically on and inorganic components (halides, alkalis, ash) present Fig. 4. in the syngas can deactivate the catalysts and must be removed prior to catalytic conversion. The formation of Table 1 Lignocellulosic Facilities as at February 2009. tars, and measures to deal with their removal, are significant challenges in biomass gasification. Pilot1 / Commercial3 Advances in gas clean-up and catalyst preparations are Demonstration2 also needed in order to make large-scale biomass to Biochemical 25 9 liquid facilities practical. Thermo Chemical 5 3

ECONOMICS Note: 1. Pilot Scale is R&D Both the biochemical and thermochemical pathways 2. Demonstration Scale is < 10 ML/yr 3. Commercial Scale is > 10 ML/yr require sophisticated processing steps that have higher operating costs and need significant capital investment United States compared with grain-based ethanol processes. Based Currently the US has a target of 136,260 million litres on the current state of technology, capital costs for per year (ML/yr) of renewable fuels production by biochemical cellulosic ethanol are estimated to be 2022. The US Renewable Fuels Standard calls for between US$4.03 and $5.60 per US gallon of annual 60,560 million liters to come from lignocellulosic capacity (8, 9). Operating costs are estimated to be sources. The driving force for this requirement is between US$1.34 and $1.69 per US gallon, depending primarily energy independence; however green house upon the assumptions made about feedstock costs, reduction is a significant motivating factor for the enzyme costs, and the kind of pretreatment to be inclusion of lignocellulosic based fuel. employed (8,9). Projected capital costs for future plants employing anticipated improvements in Demonstration-scale cellulosic ethanol plants are under biochemical conversion are estimated to be US$3.33- construction as part of the government’s goal to make 4.44 per US gallon ethanol annual capacity with cellulosic ethanol cost competitive by 2012. The plants operating costs dropping to US$0.40-0.89 per US cover a wide variety of feedstocks, conversion gallon of ethanol (10). The US Department of Energy technologies and plant configurations to help identify (DOE) has determined that competitiveness with viable technologies and processes for full-scale petroleum can be achieved at an ethanol production commercialization. All demonstration plants, which are cost of US$1.07/US gallon (in 2002 dollars) and aims sized at 10% of a commercial-scale , are to achieve this goal by 2012 (5). This compares to the expected to be operational by 2012. Commercial-scale production cost of Brazilian sugarcane ethanol of plants are in the planning stages. Demonstration and US$0.81/gal. commercial plants include:

• Abengoa - Abengoa is using a $76 million DOE Lignocellulosic based ethanol has a further advantage grant to develop a 42 ML/yr of cellulosic ethanol over starch based ethanol in that the feed stock is not integrated biorefinery, in Hugoton, Kansas. The commodity based and subject to brokers and trader biomass plant will be situated next to a speculation on pricing. Lignocellulosic based conventional cereal-to-ethanol facility to share feedstocks avoid the arbitrage that starch-based ethanol feedstocks, including wheat and corn . is subject to; project developers are better able to Both enzymatic hydrolysis and gasification will be forecast and manage feedstock costs reducing project part of the integrated biorefinery. Ethanol is developing a 72 ML/yr demonstration project in produced through enzymatic hydrolysis, while heat Fulton, MS. Concentrated acid hydrolysis is and power are generated using gasification. reported to have high sugar yields (>90%) and can Currently the plant processes 70 tpd of biomass. be easily adapted to a variety of feedstocks. Acid The plant is being expanded to handle up to 1500 recovery and handling have been viewed as tpd. Steam explosion pre-treatment will be used barriers to widespread use of this process. prior to enzymatic hydrolysis. Since mid-2007, • Coskata has developed gasification to ethanol Abengoa has operated a pilot plant in York, NE conversion technology that includes syngas using . 0.08 ML/yr of ethanol can be cleaning, a proprietary syngas fermentation produced using enzymatic hydrolysis and organism and ethanol recovery using per- fermentation of C5 and C6 sugars. Abengoa also evaporation. Coskata claims to be able to produce has a demonstration scale plant in Spain (Fig. 3) cellulosic ethanol for less than the DOE benchmark price of US$1.07/US gallon. The Coskata process has been developed quietly, intentionally keeping a low profile. Coskata developers have been awarded 16 patents and based on Argonne National laboratory analysis is showing 7.7 times the energy output to energy • input. Coskata has backing from GM and Khosla • Ventures. They have constructed and • commissioned a semi-commercial demonstration • facility at the Westinghouse Plasma facility in Madison, Pennsylvania. Coskata is developing plans for a 200 to 400 ML/yr commercial scale

ethanol facility. Fig. 3 Abengoa, Castilla, Spain. • Fulcrum- is developing the Sierra Biofuels Plant to convert 90,000 tons per year of • Alico had partnered with New Planet Energy, LLC municipal solid waste (MSW) to approximately to develop and commercialise gasification and 40 ML/yr of ethanol. Fulcrum is providing biological fermentation of ethanol from syngas. financing, design and construction services for the Alico has decided to withdraw from this project. facility to be located near Reno, Nevada. The New Plant Energy has partnered with INEOS bio Sierra Biofuels project uses a plasma enhanced to INP BioEnergy and develop a 30 ML/y gasification to create syngas from MSW and a gasification based project in Florida. proprietary catalytic technology to convert the • Alltech, through its subsidiary Ecofin, was syngas to ethanol. Start-up is planned for 2012. planning to develop a demonstration scale facility • ICM has received DOE funding to construct a in Kentucky. Plans are currently on hold. 10 ML/yr cellulosic ethanol demonstration plant to • Algenol are developing algae strains to convert be co-located at the existing 190 ML/yr corn-based CO2 to ethanol, using photo-bioreactors they clam ethanol plant in St Joseph Missouri. The facility to produce up to 6000 USgal/acre of ethanol. will process a variety of feed stocks, including Algenol have partnerships with Dow Chemical, sorghum and switchgrass as well as corn stover Linde Group, Valero and Biofields. Algenol have residue. The process utilises biochemical been selected for a $25 million DOE biorefinery conversion technology - Novozymes are a grant to be built in Freeport, TX. collaborator – with simultaneous saccharification • American Energy Enterprises (AEE) has proposed and fermentation. Significant benefits are to be construction of a cellulosic ethanol facility in New achieved via integration with the corn-ethanol Milford, Connecticut. The plan is build one process and utilization of the vast amounts of production line with a capacity of 30 to 38 ML/y carbon dioxide that are given off. ICM intends to and then add additional lines reaching an ultimate have the plant operational by Q4 2010. capacity of 300 to 380 ML/y. AEE intends to use • KL Energy have developed a process using a mild plant biomass and wood waste as a feed stock for pre-treatment, they operate a 1.0 tpd demonstration the ethanol facility. plant in Upton, Wyoming. KL Energy has 5 • Bluefire Ethanol is developing a 15 ML/yr pilot commercial project under development, 2 in the facility in Lancaster, CA to demonstrate US and 3 in Brazil. proprietary concentrated acid hydrolysis. This • Mascoma has a demonstration plant (0.8-1.9 facility will focus on sorted cellulosic waste ML/yr) in Rome, NY, evaluating multiple diverted from landfills. Bluefire are also feedstocks including hardwood. Biochemical technology, based on thermophilic bacteria is used. A simple pretreatment step precedes a low-cost planning a 151 ML/yr commercial development in cellulose hydrolysis and fermentation Consolidated Kinross, Michigan by 2012 using the CBP Bioprocessing stage (CBP). The plant has had a biochemical process. phased start up from June 2008. Mascoma is also

Legend: Thermochemical Biochemical Pilot / Demonstration Pilot / Demonstration Commercial Commercial

Fig. 4 Global and Lignocellulosic Ethanol Facilities

• Pacific Ethanol have signed a memorandum of • Range Fuels - Range Fuels is building the largest understanding with Lignol Energy Corporation to commercial plant in the USA in Soperton, Georgia. investigate co-locating a Lignol based Biorefinery The site, already under construction, was to at a Pacific Ethanol facility. Lignol was awarded a produce 76 ML/yr by the end of 2009, but now DOE grant for the development of a cellulosic aims for 38 ML/yr by 2010 before ramping up to ethanol demonstration plant. 378 ML/yr. This plant uses novel gasification • POET has a pilot-scale cellulosic ethanol facility in technology producing syngas and then mixed- Scotland, South Dakota. This plant is producing alcohol synthesis with metal catalysts for methanol cellulosic ethanol from corn cobs at a cost of $0.62 production. Challenges exist with significant per l ($2.35/USG). POET is developing Project proportions of tars from biomass as feedstock, Liberty which is a $200+million/95 ML/y compared to fossil fuels. cellulosic ethanol plant in Emmetsburg, Iowa plant • Verenium have partnered with British Petroleum • Raven BioFuels, Pure Energy, Eco-Energy and creating a Joint Venture called Vercepia which is Price BioStock have partnered to develop two constructing a 136 ML/y in Highlands Florida, cellulosic ethanol projects, which are each in start up is planned for 2012. Verenium is various stages of development: operating a 5.5 ML/yr demonstration facility in ∑ A 79.5 ML/yr plant based on wood waste is Jennings, Louisiana. The demonstration plant is being developed in Mississippi and will located adjacent to Verenium’s existing integrated produce furfural in addition to ethanol. cellulosic ethanol pilot plant that has been ∑ A memorandum of understanding has been operational since 1999 and capable of processing signed with the Kamloops Indian Band in about 2 t/d of biomass. The Verenium process British Columbia. Biomass suitable for uses dilute acid hydrolysis followed by steam supporting a 26 ML/yr ethanol facility is part explosion, liquid/solid separation, followed by of the MOU. Furfural, Hydroxymethol separate C5 and C6 sugar fermentation. Proprietary Furfural, lignin cake will also be produced as enzymes are used for the saccharification of part of the process. The PureEnergy Process cellulose. uses dilute acid hydrolysis with separate C5 • ZEAchem have developed a hybrid process results and C6 fermentation. in very high yields of ethanol. C5 and C6 sugars are fermented to acetic acid using proprietary organism which give off no CO2. Acetic acid is working with Pacific Ethanol on the development converted which are subsequently of a demonstration plant. hydrogentated to make ethanol. Hydrogen is obtained through gasification of the Lignin Details of facilities under construction or planned in the removed from the biomass. rest of the world are discussed below:

Canada South America The Canadian government has set it sights on a target • Brazil is today producing ~ 40% of the world’s of 5% renewable fuel in gasoline by 2010 and 2% ethanol from sugar cane. Yields vary from 6,600 – renewable fuel in diesel by 2012. To support this, the 7,500 L/ha which means production costs half federal government has established funding of C$550 those of US corn-based ethanol processors. million dollars for pilot plants and process development Therefore, there has been relatively low interest in and pre-commercial development, with a further C$500 second-generation bioethanol. However, recent million for demonstration scale facilities and to assist studies made by Brazilian National Development with bridging the gap between development and Bank (BNDES) together with FAO show that commercialization of cellulosic ethanol technologies. when fermenting and sugar cane the Facilities under construction or planned (11) include: ethanol yield could reach 13,000 L/ha. • Enerkem, Westbury - A 5 ML/yr cellulosic ethanol • Dedini, Sao Paulo, Brazil - The sugar and ethanol commercial demonstration plant has been co-operative Copersucar is supporting the Dedini comissioned by Enerkem in Westbury, Quebec. S/A Indústrias de Base pilot plant using Rapid The plant will use thermal gasification and Hydrolysis (DRH). The pilot plant started catalysis technology to produce ethanol and operations in 2007 and can produce 1.81 ML/yr. methanol from treated wood waste (end-of-life The process uses an initial pretreatment with cycle power poles). The methanol and ethanol organic solvents followed by dilute acid hydrolysis production modules are to be added early 2009. and fermentation stages. C5 and C6 sugars are The Enerkem themochemical process yield is 360 separated from lignin using an acid wash. Dedini L/t wood waste. Enerkem has partnered with claims a 30% increase in ethanol yields for a GreenField Ethanol, a corn ethanol producer, to sugar-based ethanol plant with integration of the commercialise the Enerkem technology. A 36 bagasse conversion process. Dedini, the world’s ML/yr ethanol/methanol plant is planned for biggest producer of sugar cane ethanol, expects Edmonton, Alberta, utilising sorted municipal solid start-up of its first commercial scale plant in 2012. waste, start up is scheduled for 2011 • Chile targets producing second-generation • Iogen, Ottawa - Since 2004, Iogen has operated a bioethanol from forest biomass within the next five demonstration-scale plant in Ottawa producing 2.5 years. Bioenercel is one of the two consortiums ML/yr of ethanol from 30 t/d agricultural residues, created for this development work. It has a five- including wheat, and straw. The year budget of US$7 million and is supported by technology can also be used successfully with the Chilean government, two public universities as hardwoods, but not softwoods. A modified steam well as pulp and paper companies Arauco, CMPC explosion pretreatment is used to liberate the and Marisa. Bioenercel is not only supposed to cellulose, followed by enzymatic hydrolysis and develop and adapt technologies but also create fermentation of both C5 and C6 sugars. Ethanol necessary infrastructure for bioethanol production. yields of 340 L/t of fibre, are reported. Lignin is The current laws in Chile require that, before the separated and used to generate process steam and year 2020, 10% of the fuel used by cars will be electricity. Iogen has partnered with Shell since replaced by bioethanol or . 2002. Iogen’s is working to develop a 70 ML/y commercial plant in Prince Albert, Sask. The Europe availability of straw, combined with government • Abengoa, Spain - Abengoa Bioenergy has been support, were key factors in this decision. This operating a biomass-to-ethanol pilot plant since the will be first facility to take advantage of the end of 2007 at the Biocarburantes Castilla y León NextGen Biofuels fund. grain-ethanol plant in Babilafuente, near • Lignol has commissioned a pilot plant using the Salamanca in Spain. 5 ML/yr are produced from biochem-organosolv process, capable of producing wheat and barley straw using enzymatic hydrolysis 0.1 ML/yr of ethanol, at their research facilities in (glucose). A steam explosion pretreatment stage, Vancouver, BC. The Alcell technology, originally from SunOpta, is currently being installed and will developed by General Electric and Repap start up early 2009. In the second phase, it is Enterprises, uses a solvent-based pretreatment and intended to separate the lignin and pentose sugars produces ethanol and High Purity Lignin (HP-L™) as co-products. (See also Abengoa in United from hardwood and softwood residue. Lignol are States section). • Weyland have developed a concentrated acid plant at the research centre at Varkaus mill for the hydrolysis process with very high recovery of acid. production of biofuels from wood residues. This is They operate a pilot plant in Bergen, Norway and a joint venture between Stora Enso Oyj and are developing a demonstration scale facility Oil Corporation. design to convert wood chips to ethanol. Statoil is • UPM Kymmene, Finland – Finnish pulp and paper partially funding the project. company UPM Kymmene and renewable fuel • Chemrec, Pitea, Sweden – Chemrec has developed supplier Lassila and Tikanoja are testing a gasification process to convert pulp mill black bioethanol production from the pulp-based waste liquor (BL) to liquid fuels including ethanol. A created by the paper industry. During the pilot BL gasification development plant in Pitea, tests ethanol and energy were produced from Sweden is located next to the Smurfit Kappa commercial and industrial waste, such as paper, Kraftliner mill and the research institute ETC. The cardboard and wood. By developing waste gasifier uses pressurized oxygen and is capable of processing units, energy company St1’s gasifying 20 t BLS/d, producing a synthesis gas division intends to produce 70 ML/yr of bioethanol that requires little cleanup. Chemrec are currently by the end of 2011. St1 already has two involved in supplying Dimethyl Ether (DME) for 1 commercial plants operating using food industry year pilot project. This project will make DME waste as raw material. UPM is also developing from Gasified black liquor to determine the project for the production of Bio-oil and Fischer viability of biomass produced DME as a diesel Tropsch liquids. substitute. A commercial-scale BL liquor gasification plant has been operating at Weyerhauser’s New Bern mill in the US since 1996, and was rebuilt in 2003 increasing capacity to 300 t BLS/d (Fig. 5). Integration of a BL gasifier allows mills to produce liquid fuels and increase recovery capacity. At the New Bern mill the unit provides 15% of the mills BL recovery capacity. • Chempolis have developed a unique pulping

process using formic acid that creates a clean cellulose suitable for conversion to ethanol. The formicobio process produces fuel grade ethanol Fig. 5 Weyerhauser, New Bern, USA from wood and non-wood sources. • St1 out of Finland has developed two processes: a • INBICON, a subsidiary of DONG energy food waste to ethanol processes, Etanolix® and a Denmark, grew out the Elsam work on agriculture variation which converts woody biomass to residues to ethanol. Inbicon have commissioned a ethanol named Bionolix™. commercial demonstration plant at the Kalundborg • SEKAB, Ornskoldsvik, Sweden – SEKAB, in coal fired power station. The commercial conjunction with Etek Etanolteknik AB, has been demonstration plant converts 30,000 tpy of straw operating a bioethanol pilot plant since 2004 at its to 5.4 Ml of ethanol, 13,100 t of lignin and 11,250 Domsjo industrial site. The feedstock is pine wood t of C5 molasses. The principal purpose of the chips, but other biomass such as bagasse, wheat demonstration plant is to show that DONG and corn stover, energy grasses and recycled waste Energy’s second-generation technology can be can be used. The plant has a maximum wood applied on a large scale, and can be integrated with capacity of 2 BDT/d and ethanol production of a power station. Inbicon, Great River Energy and 0.14 ML/yr. The process is based on multi-stage Otoka are currently developing plans for a weak acid hydrolysis, a detoxification stage prior commercial cellulosic ethanol plant which will to fermentation, and separation of lignin using a consume 400,000 tpy of wheat straw and will be membrane filter. Recent work has focused on located in North Dakota. improving the ethanol yield using pentose- • BioGasol is constructing a 5 ML/yr demonstration fermenting microorganisms. For cost reasons, plant in Denmark, called the BornBioFuel (BBF) enzymes are not used. Scale-up of this technology project. The plant, located on the island of is planned for 2010-11 with the construction of a Bornholm, will demonstrate the potential of the development facility of 6 ML/yr and a 120 ML/yr Biogasol technology (see Pacific Ethanol) to commercial plant in 2014, utilising wood waste produce ethanol from a diverse mixture of and sugarcane bagasse. biomass, including local available agricultural • Stora Enso, Varkaus, Finland - Plans have been residues and other low cost cellulosic feedstocks. announced to build a demonstration gasification • HCL Technologies out of Israel are implementing • Ethtec, Australia - Ethtec, a Willmott Forests a concentrated hydrochloric acid hydrolysis of subsidiary, is currently constructing a pilot plant woody biomass. The focus is on cost reduction for cellulosic ethanol production at the NSW Sugar and technology improvement. The pilot plant will Milling Co-operative Harwood Mill and Refinery be built at the Southern Research Institute in North near Maclean in northern NSW. The plant will use Carolina. hydrolysis and fermentation technology developed • TMO Renewables, Guildford, UK - The UK's first in collaboration with the University of Southern cellulosic ethanol demonstration facility has been Mississippi and the University of New South built using biochemical conversion which Wales. The process uses ‘induced phase incorporates their unique thermophilic bacterium separation’ for recovery of ethanol eliminating the for fermentation at 60-70ºC. Feedstocks that can need for conventional distillation, significantly be processed include agricultural waste, wood improving the energy balance of the process and chips, paper and municipal waste. reducing the environmental impact of the distillery. It is planned to use wood residues (including pine), Japan, Australasia, Asia bagasse and other biomass for the production of • BioEthanol Japan - The BioEthanol Japan plant in ethanol. Osaka Prefecture has capacity of 1.4 ML/yr and • Pure Power, Singapore – Pure Power has had plans to boost production to 4 ML/yr in 2008. purchased the NZ-based BioJoule lignocellulosic Wood construction waste is used as feedstock and conversion technology for the production of technology from Verenium. bioethanol, natural lignin and xylose. The intended • COFCO/Sinopec and Novozymes are collaborating feedstock is the wood crop Salix, a variety of to build a demonstration cellulosic ethanol plant in willow. A unique washing process is used to Zhaodong, Heilongjiang province. The feedstock preserve and recover the lignin which can be used will be corn stover and corn cobs. in paints, glues, resins and other phenolic • Honda-RITE, Japan - collaboration between chemicals which are currently derived from Honda and RITE (Research Institute of Innovative petroleum. It is estimated that 80% of the overall Technology for the Earth) aims to initially develop revenue will be derived from the lignin and xylose laboratory scale production of cellulosic ethanol by-products using biochemical process, with scale up to pilot • LanzaTech, New Zealand – This start-up energy plant size envisaged. company has demonstrated the microbial • Marubeni, Saraburi, Thailand – A 3 ML/yr conversion of carbon monoxide into ethanol. The cellulosic ethanol plant was opened in late 2008 company envisages that the process can be co-located with a sugarcane-ethanol plant retrofitted to any industrial facility to generate (Marubeni and Tsukishima Kikai Co Ltd). The ethanol from the carbon monoxide component of sugarcane bagasse will be the primary feedstock high volume waste flue gases. Scaling-up of the and Verenium’s process technology will be used. technology is planned. • China Resources Alcohol Corporation, China - • Scion, Rotorua, New Zealand – The CRAC is the second largest ethanol producer in Lignocellulosic Bioethanol Initiative is a China and has been operating a cellulosic ethanol collaboration between Scion, Verenium, Carter pilot plant in ZhaoDong City, since 2006. Corn Holt Harvey, BP and Beca AMEC that is stover feedstock is processed using SunOpta’s developing a biochemical route using softwoods modified steam explosion technology followed by for ethanol production. A pilot plant is being enzymatic hydrolysis. CRAC's goal was to install developed. 6 ML/yr of cellulosic ethanol capacity by the end of 2007 and 1,250 ML/yr by 2012, the most SUMMARY ambitious target in the world. Substantial investment is occurring in conversion • Mission NewEnergy, India – A pilot plant of 0.07 technologies and in determining the most economic, ML/yr cellulosic ethanol utilises agricultural waste practical and cleanest technology for the production of (wheat//corn/barley straw, and in the future cellulosic ethanol. Pilot plants have successfully , an oil-seed tree) using a novel demonstrated the production of ethanol from hydrolysis process. Lignin is separated from the feedstocks, such as agricultural waste, but the cellulose and hemicellulose prior to hydrolysis, conversion of wood waste, particularly softwoods, which is conducted without the use of any continues to be more challenging. enzymes. Yields of 500 L/t of feedstock are reported which is 36% more efficient than It is likely there will be no single preferred conversion competing cellulosic ethanol technologies. A technologies for the production of cellulosic ethanol, commercial scale plant is planned. but rather technologies appropriate for specific feedstocks. For example, the high ash content of many may prohibit their utilisation in the gasification 10. Aden A, Ruth M, Ibsen K, Jechura J, Neeves K, et pathway, but these feedstocks show high conversion al., Lignocellulosic biomass to ethanol process yields using enzymatic hydrolysis technologies. design and economics utilising co-current dilute acid prehydrolysis and enzymatic hydrolysis for Construction of the first large-scale demonstration corn stover. National facilities is underway. The success of these plants in Laboratory, Report NREL/TP-510-32438, June demonstrating a cost-effective sustainable conversion (2002). process for ethanol will open the way to the commercialisation of second generation biofuels. 11. Wood, Susan M. and Layzell, David B. BIOCAP Significant reductions in operating costs are needed to report, June 27, 2003 A Canadian biomass achieve the goal of producing cellulosic ethanol for less Inventory: Feeds for a Bio-based Economy. than US$1.07/US gallon. The availability and cost of raw materials will determine the size of the plant – more expensive biomass will require larger facilities in order to offset the cost of the investment. The availability of financing, particularly the willingness of governments to share in the scale-up risks with private industry, will also be critical to commercialisation. Co- location with existing infrastructure and facilities, such as power plants, grain-ethanol plants, pulp and paper mills, where various synergies can be achieved, has many advantages over stand-alone plants.

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