S1041: The Science and Engineering for a Biobased Industry and Economy
(Multistate Research Project)
S1041: The Science and Engineering for a Biobased Industry and Economy
Duration: 10/01/2013 to 09/30/2018
Statement of Issues and Justification
A. Use of increased renewable resources will require deliberate development of technologies for efficient use of resources due to three converging issues: (1) decrease in productive agricultural land areas under urbanization pressures; (2) clearing of land areas using unsustainable methods; and (3) increasing world population with an increased standard of living including a clean environment. One billion hectares of land will be cleared by 2050, resulting in the release of three Gt/year of greenhouse gases (Tilman et al., 2011). Global population will reach nine billion by 2050, resulting in increases in global food demand from 2005 to 2050 (Tilman et al., 2011). Breadth of these intersecting problems are so vast that constructive solutions can be designed and implemented only through collaborations crossing traditional disciplinary boundaries.
The objectives of this project are to address research relating directly to SAAESD Goal 1 F (biobased products) and H (processing agricultural coproducts); research will influence Goal 5 B (rural community development and revitalizing rural economies) indirectly. Because renewable energy systems occupy large land expanses, they are typically not located in urban areas, promoting economic development of rural US communities. Transitioning from sequestered-carbon sources such as oil, natural gas and coal, to more renewable energy systems requires research and development work. Without this productive research, the technical capacity to switch from a sequestered-carbon economy to a diverse bioresource-based economy will be severely hampered with unanswered questions, undeveloped technologies, and under-delivered capacity in production and utilization of bioresources. Research proposed herein is designed to help address these limitations as conducted by professional scientists and engineers either directly with or strongly associated with the Land Grant University system.
This project is written at a time when US natural gas has increased in productivity and decreased in costs. The natural gas production was 22.1 trillion cubic feet in the first nine months of 2012 compared to 21.0 for the same period in 2011. Although, natural gas may be considered the energy panacea for the next decade, natural gas combustion is a net emitter of greenhouse gases. Natural gas can certainly play a major role in assisting in the transition from sequestered-carbon based energy systems to renewable ones. However, due to continual increases in atmospheric carbon dioxide concentrations economically viable renewable energy systems must be developed and implemented. The Land Grant University system can partner with important policy-setting agencies including United States Departments of Agriculture (USDA), Energy (US DOE), Defense (US DOD), and the National Science Foundation (NSF) for doing the research that will allow us to meet our renewable energy production goals.
B. How S-1041 enabled new renewable energy industries.
Increasing the breath of renewable energy production systems includes the production of power and second-generation liquid biofuels, including biomass-derived power generation. Researchers in the S-1041 Multistate project are advancing this goal through research into most facets of bioenergy production systems, as detailed below.
Efficient feedstock supply chains are needed at commercial scale to enable the successful deployment of biobased systems. Progress was made in securing an abundant, economical supply of biomass feedstock delivered with predictable specifications that meet conversion needs. Biological feedstocks from across the US, ranging from the warm, humid southeast to dry, cool northern latitudes, representing various Land Grant University partners, were evaluated for yield, composition, and other characteristics. Feedstocks include switchgrass, giant miscanthus, energy cane and sweet sorghum with dry matter yields of 36-41 Mg/ha, 30 Mg/ha, 83 Mg/ha and 12-22 Mg/ha, respectively (West and Kincer (2011); Heaton et al. (2008); Heaton et al. (2010); Bischoff et al. (2008); Aita et al. (2011); and, Singh et al. (2012)). Camelina and other oilseed crops were evaluated as potential feedstock for biodiesel and aviation fuels, and included camelina cultivar development for higher yield and improved oil content/profile and camelina cropping system development. The yield potential of existing Conservation Reserve Program (CRP) were evaluated for different climate and geographic regions with an aim to increase yield, sustainable production, and less impact to environment and wildlife habitat.
The impact of soil type and fertility treatment on productivity and composition of switchgrass, tall fescue and reed canarygrass determined that composition was greatly affected by species and treatment, with fewer differences due to soil type. Prediction of biomass composition was improved using Fourier transform near-infrared (FT-NIR) spectroscopy coupled with multivariate analysis. A generalized, single broad-based predictive model for multiple types of biomass feedstock was developed using cornstover and switchgrass to predict concentrations of glucan, xylan, galactan, arabinan, mannan, lignin, and ash. Both cross-validation and independent validation supported a single FT-NIR model for both species, and results indicated the method's potential for wheat straw (Liu et al. 2010).
Innovative methods for biomass physical property measurement were developed. For example, 3D laser scanner images were analyzed using image processing software. Physical property determination using 3D scanning and image analysis determination methodology was an accurate, non-invasive, and highly repeatable (CV <0.3%) alternative. A sieveless particle size distribution analysis method using computer vision was developed.
Bulk density, a major logistics factor in handling biomass, is a strong function of the size and shape of the particle and particle density. Mean loose-filled bulk densities were 67.5±18.4 kg/m3 for switchgrass, 36.1±8.6 kg/m3 for wheat straw, and 52.1±10.8 kg/m3 for corn stover (Chevanan et al. 2011). Pressure and volume relationship of chopped biomass during compression with application of normal pressure was observed to fit well for Walker model and Kawakita and Ludde model. Parameters of the Walker model correlated with compressibility at a Pearson correlation coefficient greater than 0.9.
Densification of biomass feedstocks was applied to switchgrass and woody biomass subjected to fast pyrolysis, and woody biomass fractionated into lignin, cellulose and hemicelluloses streams. Densified switchgrass, wheat straw, giant miscanthus, elephant grass, cotton gin trash, and softwood forest trimmings, were produced through pelleting and briquetting with resultant heating values ranging from 17,908 to 18,839 kJ/kg. Biomass specifications, energy, and costs for feedstock densification were identified particularly for pellets, cubes, or grinds. Minimum-pressure densification was investigated due to recognition of high cost and in-efficient pressure application associated with the pelleting process. Specific energy for minimum-pressure densification ranged from 0.25 to 2 kJ/kg, which was significantly less than energy to produce pellets. Integrated biomass pretreatment (AFEX) and densification process, namely billet compaction, of corn stover, switchgrass and prairie cordgrass indicated that pretreated billets hold together well without use of added binders.
Flowability of chopped switchgrass, wheat straw, and corn stover at pre-consolidation pressures of 3.80 kPa and 5.02 kPa indicated Mohr-Coulomb failure. Results of measured angle of internal friction and cohesive strength indicated that typical chopped biomasses cannot be handled by gravity alone. Unconfined yield strength and major consolidation strength used for characterization of bulk flow materials and design of hopper dimensions were 3.4 and 10.4 kPa for chopped switchgrass; 2.3 and 9.6 kPa for chopped wheat straw and 4.2 and 11.8 kPa for chopped corn stover (Chevanan et al. 2009). These results are useful for development of efficient handling, storage, and transportation systems for biomass in biorefineries.
Although, great strides were made in terms of better predicting biomass crop yields and quality on selected areas, there still remains knowledge gaps in terms of: 1) expected yields of these energy crops throughout US available land; 2) spatial and temporal variations in yield and supply due to climate and soil conditions; 3) harvesting and handling of these low bulk density materials; and, 4) identifying target physical properties important at the interface of processing and conversion.
Cellulosic biomass conversion to industrial chemicals and fuels is performed via thermochemical, biochemical or a combination of these platforms. Unfortunately there is no clear technology winner and both conversion platforms have tradeoffs. The thermochemical platform is robust in terms of feedstock processing, but somewhat complicated in terms of the resulting product portfolio (Sharara et al. 2012). Thermochemical conversion includes gasification, pyrolysis or a combination of these technologies. The effects of furnace temperature, steam to biomass ratio and equivalence ratio on gas composition, carbon conversion efficiency and energy conversion efficiency of the product gas were investigated with temperatures of 650, 750 and 850 °C, steam to biomass ratios of 0, 7.30 and 14.29 and equivalence ratios of 0.07, 0.15 and 0.29. Gasification temperature was determined to be the most influential factor in terms of hydrogen and methane contents, carbon conversion and energy efficiencies. A steam to biomass ratio of 7.30 resulted in maximum carbon conversion and energy efficiencies. Effect of initial biomass composition on gas compounds product composition and furnace temperature profile was modeled; predicted flow rate of hydrogen was similar, but the predicted flow rate of methane was lower (Kumar et al. 2008; Kumar et al. 2009). Gasification studies were reported for wood chips and agricultural residues (Gautam et al. 2011a), for pelletized biomass (Gautam et al. 2011b) and for coal/biomass mixtures (Brar et al. 2012).
A downdraft gasifier was designed, fabricated and extensively tested using 11.6% dry basis switchgrass. Results consisted of the following: 1) specific air input rate, 542 kg/ h-m2 of combustion zone area: the average values for hot gas and cold gas efficiencies were 82 % and 72 %, respectively; the lowest heating value of gas was 1566 kcal/Nm3; CO, H2 and CO2 concentrations were 23 %, 12 % and 9 %, respectively; the corresponding average specific gasification rate was 663 m3 dry gas/h-m2 of combustion zone area; with specific air input rates of 647 kg/h-m2 of combustion zone area, CO2 concentration increased to 14 %, while the CO and H2 concentrations decreased to 19 and 10 %, respectively; and, anticipated establishment of high temperature swirling flows in annular section of pyrolysis and tar cracking section could not be achieved (Patil et al. 2011).
Wang et al. (2012) investigated the possibility of fermenting bio-oils sugars. New pyrolysis systems, including microwave assisted pyrolysis (MAP) and electromagnetic technologies for rapid pyrolysis, were developed and tested at the pilot scale and as mobile pyrolysis units. The mobile unit was 5 x 2.5 x 3.5 m with a processing capacity of 0.5 ton/hr (Wan et al. 2009a). Corn stover and aspen wood pellets were pyrolyzed using microwave heating with or without addition of catalysts (Moen et al. 2010). Medal oxides, salts, and acids, including K2Cr2O7, Al2O3, KAc, H3BO3, Na2HPO4, MgCl2, AlCl3, CoCl2, and ZnCl2, were pre-mixed with corn stover or aspen wood pellets prior to pyrolysis, which yielded three product fractions: 1) bio-oil; 2) syngas; and 3) charcoal. The addition of KAc, Al2O3, MgCl2, H3BO3, and Na2HPO4 were found to increase bio-oil yields. Increases in bio-oil yields were accompanied by changes in charcoal or syngas yields or both, suggesting that the catalysts used affected the fractional yields through different mechanisms. The catalysts could function as a microwave absorbent to speed up heating or could promote the so-called in situ upgrading of pryoltic vapors during MAP of biomass. Pyrolysis studies were conducted using corn stover (Capunitan and Capareda 2012), switchgrass (Iman and Capareda 2012), and sweetgum (Wang et al. 2012).
Catalytic-based processes were developed by S-1041 members (Street et al.
2012a; Street et al. 2012b; Street and Yu 2011). The upgrade, via catalysis, of synthesis gas to useable fuels was investigated (Yan et al. 2012a; Yan et al. 2012b). Specifically, catalysts may play an important role in solid-to-vapor conversion and reforming of vapors during microwave assisted pyrolysis (MAP) biomass processing. GC-MS analysis indicated that use of the catalysts significantly reduced the number of chemical species in the resulting bio-oils. Chloride salts suppressed most reactions during the pyrolysis. Adding 8 g MgCl2 per 100 g biomass resulted in bio-oils that contained more than 80% furfural, indicating that MgCl2 is effective in improving product selectivity of MAP processes. A number of biomass, including microalgae, corn stover, poultry litter, peanut, pinewood and switchgrass, was tested as MAP feedstocks (Du et al. 2011; Wan et al. 2010; Wan et al. 2009b). Microalgae-produced MAP bio-oils displayed better quality in terms of heating value, oxygen content, viscosity and density than those obtained from lignocellulosic biomass. Enhanced quality of microalgae bio-oils could be due to the higher concentration of hydrocarbons and lower concentration of oxygenated compounds. New Generation Fuels, a commercial entity, determined that microalgae bio-oils could readily be mixed with a commercial liquid fuel without any pretreatment, showing excellent fuel and combustion properties (Wan et al. 2010). Effect of catalyst loading and nature of support was examined on the gas shift reaction (Haryanto et al. 2011). The use of biomass was investigated in the Fischer-Tropsch reaction (Hu et al. 2012). Catalytic conversion of syngas to mixed alcohols over catalysts was studied (Lu et al. 2012).
Although, great advances were made in terms of designing pyrolysis, gasification and catalysts, there still remain knowledge gaps in terms of integration of these technologies to produce thermochemically-based economically viable energy systems.
B.2. 2 Biochemical
As opposed to thermochemical processing, biochemical processing does not require temperatures in the realm of 500 °C. On the other hand, this processing platform is based on the saccharification of sugars that make up the plant cell wall into high quality sugar streams that will then be converted to biobased fuels or chemicals. To produce fuels using biochemical processing technologies, feedstock must be reduced in size, pretreated, hydrolyzed with enzymes and fermented (Lynd et al. 2008). Specific pretreatment methods attack different components of the cell wall, with ammonia and lime treatments resulting in the disruption of lignin, while water and dilute acid causing hemicellulose solubilization (Kumar and Wyman 2008a). The efficacies of pretreatments are rated according to their production of reactive fiber, utility of the hemicellulose fraction and limitation of the extent to which the pretreated material inhibits enzymatic hydrolysis and growth of the fermentation microorganism. Pretreatment can lead to the generation of inhibitory products such as lignin derivatives and xylose degradation products, such as furfural and formic acid (Du et al. 2010).
Members of S-1041 are actively involved in pretreatment research. Examples of work are found below. Lime pretreatment with loadings in the range of 0.02 to 0.2 g/ g of dry biomass were investigated; maximum sugar recovery from Bermuda costal grass was obtained with a loading of to 0.1 g/g of dry biomass at 100 °C for 15 min (Wang and Cheng 2011). Combinations of lime, 0.05 g/ g of dry biomass, and sodium hydroxide, 0.05 g/ g of dry biomass, place on corn stover for 6 h at 21 °C yielded 77% theoretical sugar recovery (Zhang et al. 2011). Using sweetgum wood, 1% sulfuric acid at 160 °C for 60 min in non-stirred batch reactors, yielded 82 and 86%, respectively, of theoretically available xylose and glucose (Djioleu et al. 2012). Dilute acid pretreatment processing parameters can be adjusted such that biomass can be fractionated into hexose-rich and pentose-rich streams (Zhang and Runge 2012). In addition to traditional pretreatments, processing methods, such as solid-state treatments, offer interesting options in terms of saccharification. Maceration of corncobs with rot fungus, such as Ceriporiopsis subvermispora, for 35 days at 28 °C enabled the recovery of 75 % and 40 % of theoretical glucose and xylose yields, respectively (Cui et al. 2012).
Although pretreatment is critical, this processing step unfortunately can lead to the production of inhibitory compounds that restrain the enzymatic saccharification of the carbohydrate polymers. The enzymatic saccharification step is obstructed mainly by three groups of compounds: lignin derivatives that cause non-productive binding of the saccharification cocktail (Berlin et al. 2006); xylose-derived compounds inhibiting the enzyme cocktail (Cantarella et al. 2004); and, oligomers and phenolic-derived compounds deactivating the enzymes over time (Kumar and Wyman 2008a; Berlin et al. 2006 and Ximenes et al. 2011). To lessen the effect of these inhibitory compounds and minimize the amount of enzymes used, the inhibitors must be removed by separation methods, for example, washing the pretreated biomass with successive volumes of water (Hodge et al. 2008). Members of S-1041 are actively involved in determining exactly which inhibitory compounds, produced during pretreatment, need to be minimized. By knowing exactly which compounds are the bad actors, pretreatment processing parameters can be adjusted such that their concentration can be minimized, alleviating colossal pretreated biomass water washes (Frederick et al. 2012).
Pretreatments open tightly woven biomass plant cell walls, increasing internal surface areas. With more available surface area, enzymes have access to carbohydrate polymers, hydrolyzing hemicellulose into the five-carbon xylose and cellulose into the six-carbon glucose. The hydrolysis of the treated cellulose is performed with an enzymatic cocktail composed of xylanase, ²-glucosidase, endo-cellulase and exo-cellulase. These enzymes hydrolyze hemicellulose, cellobiose as well as the middle and extremities of the cellulose polymer, respectively. It is critical to digest the plant cell wall monosacharides with the least amount of cellulase and xylanase enzymes; these biocatalysts account for the most costly component of the biochemical process and, if not used sparingly, could forfeit the economic viability of the biorefinery. Members of S-1041 are involved in enzymatic hydrolysis research. Bioreactors, such as deep-bed solid-state reactors, are developed to optimize xylanase, ²-glucosidase, endo-cellulase and exo-cellulase production (Brijwani et al. 2011). Adding adjuvants to enzymatic cocktails increases their activity. As an example, adding 2.5 g casein, the milk protein, per g of glucan allowed for a two fold reduction in enzyme loading, from 50 FPU to 25 FPU, significantly reducing enzyme costs (Eckard et al. 2012).
Reliance on fossil fuels will eventually decrease by increasing fuel efficiency standards, transitioning whenever possible to electric vehicles and manufacturing biofuels. Production of 36 billion gallons of renewable fuels by 2022 will remain in the Energy Security and Independence Act (ESIA). Second generation fuels, such as cellulosic ethanol, will eventually gain traction, as the price of oil gradually increases. Iowa will soon be the home of POET and DuPont cellulosic ethanol plants, while ABENGOA has chosen to locate in Kansas; each of these manufacturing plants will be using corn residue as feedstock. Although, great strides were made in terms of pretreatment and enzymatic hydrolysis, there still remain knowledge gaps in terms of integration of these technologies to produce second-generation production systems that are economically viable energy systems.
Great progress has made over the last five years in creating viable feedstock supply chains, deciphering between important and trivial pre and post harvest parameters, integrating thermochemical energy production systems, and designing fermentable sugar streams, there still remain knowledge gaps in understanding the environmental impact of these systems such that their carbon footprint is minimized.
C. Funding landscape: Challenges and Opportunities for the next five years
Although oil prices have stabilized over the last few years, the impetus for development of environmentally sustainable and economically viable sources of bioenergy and bioproducts is driven by the need to reduce the environmental impact of the energy industry, and US dependence on fossil fuels. The Energy Independence and Security Act of 2007 has set high standards for the production of energy from biomass. Of the 36 billion gallon per year mandated by this act, corn to ethanol contribution is limited to close to 15 billion gallons per year, with the remaining 21 billion gallons to be produced from cellulosic and other feedstocks. Subsequent studies indicate that the biomass required for production of this advanced biofuel is available, though the lack of commercial scale conversion facilities raises concern over our ability to achieve this goal. To address this need for development that is becoming more urgent by the year, agencies continue to provide broad-based funding in all aspects of bioenergy production. The most significant sources include United States Department of Agricultures National Institute of Food and Agriculture (USDA NIFA), the United States Department of Energy (US DOE), the Department of Transportation Sun Grant, and the National Science Foundation (NSF).
The National Institute for Food and Agriculture (NIFA) under the USDA manages the Sustainable Bioenergy Challenge program that has been supporting research and educational initiatives through annual funding competitions since 2009. Research funding has been approximately $10 million annually in 2011 and 2012 (USDA, 2011). USDA and DOE have also partnered to provide the Biomass Research and Development Initiative (BRDI), which provide funds to multi-institution, interdisciplinary teams working in feedstock development, biofuels, and biobased products development. These grants have been awarded nearly annually since 2003 (USDA 2012). The USDA / US DOE partnership has also existed in the Genomics Science Program that fund has supported approximately ten projects annually since 2006 in the Plant Feedstock Genomics for Bioenergy (DOE - USDA 2012). USDA also supports National Centers, such as the National Center for Agricultural Utilization Research, that have groups devoted to bioenergy research. Moreover, USDA has developed its Energy Research Education and Extension Strategic Plan which contains four goals: 1) Sustainable agriculture and natural resource-based energy production; 2) Sustainable bioeconomies for rural communities; 3) Efficient use of energy and energy conservation; and 4) Work force development for the bioeconomy. The four goals are in line and complementary to the mission of the Energy Efficiency and Renewable Energy of DOE. To attain their four goals, the USDA is aligning itself with the Land Grant Universities.
NSF has also provided two major programs designed to advance research and development in the biomass and bioenergy space. The Sustainable Bioenergy Pathways program was developed to support innovative and interdisciplinary research in basic sciences that support systems approaches to sustainable bioenergy solutions (NSF 2012a). And the Energy for Sustainability Program in the Division of Chemical, Bioengineering, Environmental, and Transport Systems is awarding nearly $10 million in research grants for fundamental and applied research in electricity and transportation fuels, with specific interest in biomass conversion and biofuels (NSF 2012b).
In 2009, the American Reinvestment and Recovery Act also provided significant investment in the biofuels industry with $800 million for biofuel research, development, and demonstration projects (Recovery Act 2009).
Related, Current and Previous Work
This proposed Multi State Project builds on the accomplishments of previous Multi-State Projects S-1007 and S-1041. The significant accomplishments as a result of participation in S-1041 include:
1) Researchers associated with S-1007 have generated over 200 peer reviewed and other publications annually, including numerous book chapters and books (Khanal. 2008; Bergeron et al. 2012), either independently or in collaboration with other experiment stations represented in S-1041.
2) Collaborative proposals were developed among S-1041 members during the 2008-2012 period. Funding success was obtained. As an example, the Biomass Research Development Initiative (BRDI) awarded $5.07 million to a Kansas State, Montana State and University of Wyoming consortium for the following proposal: Enhancing economic viability as bio-feedstock: Optimization and demonstration of the production system and bioproduct development.
3) Thirty-one S-1041 members conducted 19 site visits and evaluations of projects funded by the USDA/DOE Biomass Research Initiative (BRDI) in FY 2005, FY 2006, FY 2007 and FY 2011. Members conducted the visits in two or more person teams and generated project evaluation reports. The reports documented progress, challenges, outcomes and impacts of each project and were submitted to USDA, DOE, Office of Management and Budget and Congressional leadership to provide an update on funded projects and to guide overall program management activities.
4) Consultations with industry and presentations at bioenergy conferences and professional society meetings. It is anticipated that the proposed Multi State Project will generate similar activity.
5) Creation and approval of Bioenergy and Sustainability Technology (BST) on-line Graduate Certificate in collaboration with Kansas State, Oklahoma State, South Dakota State and University of Arkansas.
S-1041 is cognizant of the Multi-State Project SERA-38 Biobased energy research and information exchange committee, which is an extension and outreach committee aimed at complementing SDC-325. SDC-325 is also aware of the existence of NC-506 Sustainable biorefining systems for corn in the NC region, which is devoted to examining the sustainability of corn to ethanol operations. NC-506 is complementary to SDC-325 and little duplication is reported. A CRIS data search showed the projects Management of Grain Quality and Security for World Markets and Wood Utilization Research on US Biofuels, Bioproducts, Hybrid Biomaterials Composites Production, and Traditional Forest Products, which do not present significant overlap because this current project is not devoted solely either to corn or to forestry-derived feedstock. The project New Technologies for the Utilization of Textile Materials was located on the CRIS data search and some overlap is detected in Objective C Task 4.
Develop deployable biomass feedstock supply knowledge, processes and logistics systems that economically deliver timely and sufficient quantities of biomass with predictable specifications to meet conversion process-dictated feedstock tolerances.
Investigate and develop sustainable technologies to convert biomass resources into chemicals, energy, materials and other value added products.
Develop modeling and systems approaches to support development of sustainable biomass production and conversion to bioenergy and bioproducts.
Identify and develop needed educational resources, expand distance-based delivery methods, and grow a trained work force for the biobased economy
MethodsThe challenges posed in this new century in terms of energy and food will require advances in technology, sustainability and work force development. It is important to note that members of this project will formally collaborate and disseminate their results at the following professional meetings: American Society of Biological and Agricultural Engineers (ASABE) section meetings FPE-709, BE-28, PM-23/7/12 and T-11; American Institute of Chemical Engineers (AIChE); American Oil Chemists Society, (AOCS); American Chemical Society (ACS); and, the National Biodiesel Board. This project is building on the research and findings of the 2008-2013 cycle of the S-1041 project, and the following Objectives are based on these findings. This multi-state project proposes the following four objectives: Objective A: Develop deployable biomass feedstock supply knowledge, processes and logistics systems that economically deliver timely and sufficient quantities of biomass with predictable specifications to meet conversion process-dictated feedstock tolerances. Biomass type and availability is dependent on climate and soil conditions of the geographic locations. Biomass from agricultural and forestry sources is characterized by a high moisture content, low bulk density, and variable seasonal yields. This objective is to identify and evaluate biomass feedstock type and availability, characterize biomass properties, and to develop engineered systems that harvest and deliver the biomass, supplying abundant and inexpensive bio-feedstocks with predictable characteristics to biorefineries. Overall, this objective is to provide technology and data for designing supply systems that are scalable for providing abundant quantities of cost competitive biomass. Task 1: Identify biomass feedstock type and availability for selected geographic regions based on agronomic and climate conditions (MT, OK and TN). Biomass feedstock type and availability will be examined based on agronomic and climate conditions for selected geographic regions. Emphasis will be placed on identifying biological species, yield potential, and efficient production systems that rely on minimized inputs for sustainable growth of biomass in abundant quantities. Most promising genetics and agronomic practices are used to maximize biomass production under environmental conditions relevant to selected regions. Field trials of potential energy crops, including variety comparisons, development of best management practices and production systems, will be carried out at different geographic regions (MT, OK, TN). Productivity and quality of various prairie grasses, forage crops and grass-legume mixtures on Conservation Reserve Program (CRP) lands will be evaluated based on potential for biofuel feedstock (MT). The approach includes overall agronomic evaluations and site-specific crop responses over several seasons. Remote sensing technology will be developed for yield prediction in large landscape (MT). Task 2: Characterize physical and chemical properties of feedstock along the logistics supply for different geographic regions (AL, CA, MT, ND and TN). This task is to determine detailed biomass properties associated with biomass type, geographic location, and various logistics supply methods, interfacing, whenever possible, with pretreatment technologies. Physical properties include bulk and particle densities as indicators of various densification technologies and logistics supply methods (CA, TN). Flow properties will be determined due to influence on feedstock handling (AL, ND, TN). Preprocessing size reduction/grinding energy and particle spectra will be evaluated for fine grinds (AL, ND, TN). Energy content will be monitored since this indicates energy availability and feedstock quality (AL, MT, ND). Effect of storage environment, moisture relations, and feedstock quality will be analyzed (AL, ND, TN). Standard proximate chemical composition of feedstock (AL, MT) and rapid chemical analyses of feedstock, such as Fourier transform spectral techniques (AL, MT), will continue to be developed. Biomass chemical properties will be evaluated for selected types of biomass from different geographic/climatic regions (MT). Moisture content and particle size distribution of raw and preprocessed feedstock affect properties and will be incorporated into evaluations (AL, TN). Task 3: Develop and evaluate harvest, pre-process, handling, densification, storage, and transport methods for specific biomass feedstock end-users (AL, ND and TN). This task develops the technology and information for efficient, scalable supply logistics applicable to various biomass materials, regions, and end uses. Emphasis is on the delivery of premium quality feedstock at low cost. New techniques for harvesting, processing, and handling include goals of assessing both packaged and bulk methods of materials handling (AL, TN). Determination of harvest equipment design specifications is addressed for biomass crops having yield and physical properties that exceed those of forage and hay crops (TN) and forest biomass (AL). Improved packaged handling technology is emphasized. Bulk handling techniques and commercial-scale compaction technology will be developed for low moisture perennial grasses (TN) and forest biomass (AL). Biomass size reduction and separation of plant botanical components will be undertaken for efficient energy use (AL, ND, TN). Characterization of binding and agglomeration properties of biomass to reduce costs associated with transport and handling will be undertaken. Harvest, collection, and transport options of biomass to estimate and reduce the delivered cost and energy consumption during the entire supply chain of biomass resources will be examined (AL, TN). Results and methods will be shared and communicated with researchers involved in Objective C such that data is incorporated into developed models. Objective B: Investigate and develop sustainable technologies to convert biomass resources into chemicals, energy, materials and other value added products. Despite the efforts that have been made in conversion technologies, deployment of commercial facilities, using either biochemical or thermochemical platforms, is still lacking. Improving sugar, bioenergy or bioproduct yields would be valuable in enabling these bioprocesses. Integration between feedstock supply and conversion could be one step in improving yields. The multi-state community can facilitate the integration between feedstock logistics and conversion by providing insight between conversion and biomass biological and physical properties. B.1. Biological conversion technologies Task 1: Develop pretreatment methods for biological conversion processes (AR, CA, KS, KY, HI, IL, IN, LA, MI, NC, ND NE, OK, OH, OR, SD and WI). Pretreatments are essential to deconstruct biomass, releasing sugars that can be converted to bioenergy and bioproducts. Different pretreatment technologies, such as dilute acid (AR, IL, NC, ND, NE, OK), alkaline (ND, NE), ionic liquids (WI), water combined with carbon dioxide mixtures (IN), pulsed electric field, extrusion and other high shear processing (SD), hydrothermal, steam and ammonia explosion (MI), organosolv (WI), biological pretreatment (KY, OH), sulfite, or microwave pretreatments (LA) will be investigated. Effects of pretreatments on feedstocks, such as algae (HI), switchgrass (AR, ND, OK), napiergrass (NC), energy cane, tropical maize (HI), JUSETALL wheatgrass (CA), energy beets (CA), miscanthus (OH), municipal solid waste (CA), woody biomass (AR), drought- and heat-stressed plants, nontraditional oilseeds sorghum (KS), prairie cord grass (ND, SD), and coastal Bermuda grass (OR), in addition to agricultural residues, like corn (NE) and sorghum stover (ND), rice and wheat straw, or food processing residuals (CA) will be examined. When possible, pretreatment effects, using common analytical protocols developed by National Renewable Energy Laboratories, will be evaluated. Task 2: Develop conversion processes (CA, HI, IA, IN, IL, KS, KY, MN, NC, ND, NE, OH, OK, OR, SC, SD and WI). Biofuels, including advanced liquid transportation fuels, cellulosic ethanol, butanol, butanediol, propanediol, lipids, yeast- and algal-based oils or biogas (methane, H2) will be investigated, integrating feedstock pretreatment to fermentation. Use of thermostabile xylanase and cellulase and fermentation of the resulting sugars with thermotolerant microbes and xylose fermenting microbes will be examined. Conversion of straw, food processing residuals, microalgae and green grass into biogas will be conducted. Platform chemicals, such as carboxylic acids, diols, esters, furans, sesquiterpenes, biopolymers, surfactants (IA), solvents, food additives or animal feeds (single cell protein) will be researched. Optimizing yields of biosurfactant (lipopeptides) from fermentation of low-value feedstocks, and purification will be considered (IA). Biocatalysts production, namely enzymes, will be considered. The synergistic roles of different enzyme catalysts in biobased deconstruction processes will be studied. Thermotolerant microbes and a high solids bioreactor for simultaneous saccharification and fermentation will be developed. . Fed-batch hydrolysis of pretreated lignocellulosic biomass will be studied (NE). Algal production, harvest and conversion systems utilizing large-scale outdoor algal production with co-culture of filter-feeding aquatic organisms for converting algal biomass into feed protein and oils for feeds and biofuels will be designed (MO, MN). Cultivation of microalgae using industrial wastewaters will be evaluated along with fluegas from power plants to generate biogas and eventually clean biogas into clean synthetic natural gas. Task 3: Develop value-added, bio-based products from fractionated biomass (AR, CA, KS, HI, IA, IN, LA, NE, OK, TX and WI). Fractionated biomass will be examined for value-added products development including lignin-based chemicals and materials, nontraditional oilseeds and other fine chemicals. Examples include biocomposites produced by binding plant-derived proteins with agricultural residues or xyloligosaccharides, with probiotic properties, from hemicellulose, and lipid-based compounds with health benefiting properties (NE). Protein extraction from coproducts of bioethanol industry, and protein modification for aquatic and monogastric feed application will be researched (IA). B.2. Value added products and markets based on thermochemical conversion technologies. Task 1: Develop pretreatment methods (AL, CA, GA, LA, MN, MS, SD, WI and WV). AL, CA and MS will conduct pretreatment study to render feedstock more amenable to gasification. AL, GA, WV, and MN will study thermochemical conversion of biomass integrated with novel torrefaction pretreatment technologies. Specifically, the impact of torrefaction pretreatment on fast pyrolysis and gasification technologies will be investigated by GA. Energy and economic analyses of torrefaction pretreatment technology for woody biomass and energy crops such as energy cane, napier grass, switchgrass and miscanthus will be conducted in SD. WV and WI will study the hot water extraction and leaching processes to improve conversion efficiency. LA will investigate rapid feedstock drying to very low moisture contents using microwave technology. MN will investigate pretreatment of feedstock prior to microwave pyrolysis. MS will perform biomass pretreatment prior to fast pyrolysis in order to maximize anhydrosugar production. Task 2: Develop conversion processes (AL, GA, IN, LA, MN, MS, NE, OH, OK SD, TN, TX WI and WV). Electricity, heat, and power (AL, MN, MS, OH, OK, WV); fuels, such as gasoline, diesel, jet fuel, mixed alcohol, ester, solid and gas fuels (AL, MN, MS, NE, OH, OK, TX, WI, WV); and, chemicals and materials, such as polyurethane, composite, plastic, coating, fiber, rubber, asphalt, biochar (GA, IN, LA, MN, MS, OH, OK, TX, WI, WV) will be investigated. Biomass gasification, pyrolysis, and hydrothermal liquefaction processes will be conducted. Catalysts to deoxygenate biomass derived oxygenates will be developed (MN). In-situ catalytic conversion technologies will be evaluated to produce stable bio-oil, syngas, and selective chemicals (MN). The use of steam-air gasification and pyrolysis processes to produce syngas, bio-oil, biochar, and related products will be researched (NE). Electromagnetic technologies for rapid pyrolysis will be investigated. Direct conversion of algal biomass to liquid fuels through hydrothermal liquefaction and pyrolysis will be explored (MN). Fast microwave assisted pyrolysis and gasification will be investigated (MN). Conversion of cellulosic biomass and crude glycerol to biopolyols and polyurethane via atmospheric liquefaction process will be studied. Eco-friendly approach for fabricating nanofibers from cellulose and protein biomass will be developed (TX). The group also will investigate the use of catalysts in gasification, pyrolysis and hydrothermal liquefaction for improved yield and bio-crude quality. Task 3: Develop and improve catalytic upgrading processes to convert intermediates to high quality and stable liquid fuels and products. (AL, GA, MN, MS, WI and WV). Work on drop-in transportation fuels, such as gasoline, diesel, and jet fuel, from biomass feedstocks through catalytic conversion technology of intermediates will be continued. High-pressure hydro-treating and catalytic upgrading of stabilized bio-oil into green diesel and fuel additives will be studied. Task 4: Integrate thermochemical and biological conversion processes to produce biofuels and bioproducts. (MS, OH and OK). Capabilities of novel microorganisms to produce ethanol, butanol and other products will be investigated. Mass transfer capabilities of various reactor designs for syngas fermentation with a focus to identify reactor designs that increase the alcohol productivity and syngas utilization will be studied (OK). Conversion of biogas from anaerobic digestion to liquid hydrocarbon fuels will be researched (MS, OH). Non-thermal plasma assisted catalysis reactor and slurry reactor will be investigated for converting syngas to drop-in fuels (MN). Task 5: Improve methods for characterization of intermediate products and process control (GA, IN, MN, MS, OH, SD, TN and TX). Improvement of methods for characterization of intermediate products and process control using FTIR/NIR, GC-MS and NMR technology will be investigated. Knowledge of pyrolysis-derived bio-oil stability and uses, such as its application for road construction, will be developed. Methods to characterize the liquefaction production will be researched. Gasification and catalytic conversion technology using common feedstocks will be examined. B.3. Biodiesel production processes Task 1: Characterize new feedstocks. (HI, IN, LA, MT, ND, NE, SC and SD). Collaborate with Objective A to implement production of oilseed crops, such as camelina, canola and hazelnuts, in the High Plains, such as in MT, ND, NE and SD, tallow tree seeds in LA and Jatropha carcus L. in tropics in HI will be investigated. These and other fats and oils, including those from algae and oil from corn ethanol plants, will be characterized in IN and SC. Task 2: Develop an understanding of fuel quality and performance issues from emerging crops. (IN, MI, ND and NE). Storage stability and cold-weather performance of emerging crop biodiesel and related fuel blends will be studied (IN, ND). NE will provide technical assistance on engine testing of biofuels and biofuel blends to all members for-fee. Relevant ASTM analytical protocols will be shared and/or implemented among participants to enhance the research capabilities among participants in order to make results comparable across laboratories. MI will investigate properties of blends of biofuel additives with petroleum fuels. Task 3: Develop and characterize innovative processes for biodiesel production (GA, HI, LA, MN and SD). SD will determine the most robust combination of lipase enzyme, carrier and immobilization techniques for trans-esterification of crude vegetable oil. Methods to intensify reaction kinetics of the trans-esterification process and to accelerate separation processes will be developed. Algae production integrated with wastewater treatment, resulting in CO2 sequestration, will be examined (MN). GA will study the use of solid-acid catalysts to trans-esterify fatty acids and lipids into biodiesel fuels. HI and MN will develop direct in situ trans-esterification of algal biomass to biodiesel. HI will investigate metabolic pathways and networks involved in bacteria-catalyzed transesterification of tryglycerides to clean biodiesel fuels. LA will investigate in-situ transesterification using microwave technology. Task 4: Develop and utilize co-products (HI, IN, KS, LA, ND, OH, SC and SD). Conversion of crude glycerol into highly unsaturated fatty acids via algal and fungal culture will be undertaken. OH and IN will work on the development of biofuels, biofuel additives and value-added products from glycerol. ND will evaluate industrial uses of oilseed meals. OH and SC will be using coproducts of algae biomass after oil extraction and HI will work on detoxification of Jatropha seedcake, for aquaculture applications. KS will work on the development of adhesives, resins, and composites using oil meals and oil seeds proteins. LA will investigate potential uses of tallow tree seeds meal. Objective C: Utilize system analysis to support development of economically, socially and environmentally sustainable solutions for a bio-based economy. Development of environmentally sustainable and economically viable sources of bioenergy and bioproducts is driven by the need to reduce the environmental impact of the energy industry. For this, supply chains capable of providing ample biomass for the production advanced biofuels will be necessary, and these supply chains will need to be integrated with commercial scale conversion facilities and connected to viable distribution systems. This objective is to utilize existing system analysis technology to assist in the development of useable frameworks that will facilitate the development of the bio-economy. Task 1: Develop system models and data to represent integrated feedstock supply systems, including discrete processes and entire supply logistics. (CA, GA, HI, NE, NJ, OR and WI). The goal of this task is to develop models and requisite data to represent biomass production and logistics. All collaborators will incorporate experimental data into system models to analyze production, harvest, storage, preprocessing and transportation of different biomass feedstocks. Supply chains from the farm-gate to the refinery-gate will be modeled factoring in resource distribution, technology availability, and end-user needs. GA will continue to expand its supply logistics modeling effort to energy crops; biomass will consist of napier grass, miscanthus, energy cane and pine forest, including forest residues and round woods. NE will develop integrated models of feedstock collection, storage and supply for crop residues and switchgrass. Supply logistics models can be further integrated with GIS based resource mapping tool for detailed feedstock delivery cost. From data generated in Objective A, optimum scenarios for biomass logistics that are region, feedstock and bio-product specific will be identified. Task 2. Develop system models and data to assess sustainability of integrated conversion platforms. (HI, NE, NJ, NY, OK, OR and TX). The second task will focus on models and data for evaluation of bio-processes from the perspective of technical feasibility, chemical and pesticide requirements, co-product reuse, as well as GHG emission production. Whenever possible, data generated in Objectives A and B will be incorporated into the developed models. The sustainability of processes is strongly dependent on the feedstock and regional conditions, but another significant aspect of this analysis is the inclusion of dynamic considerations; in particular the evolution of sustainability metrics as the industry and technologies evolve. TX will examine the sustainability issues that surround the utilization of all co-products of the fast bed pyrolysis system, particularly recycling the syngas for drying purposes and the bio-char as soil amendment, fertilizer, briquette or activated carbon source. HI, NJ, NY and OR will work with on incorporating dynamics and uncertainty into a flexible LCA methodology for analysis of conversion processes. OK will develop modeling tools for acetogenic fermentation of syngas to allow the determination of operating parameters that result in highest alcohol productivity and investigation of various scenarios for operation, providing data toward assessment of similar systems. TX fluidized bed fast pyrolysis have been evaluated providing technical aspects of varying feedstock quality and quantity and sources and will be able to provide data toward assessment of similar systems. NE will perform life cycle assessment (LCA) research on different biofuel systems; greenhouse gas emissions and thermodynamic efficiencies will be investigated using LCAs in conjunction with crop and soil carbon modeling. Task 3. Develop integrated system models to configure, analyze and optimize bioenergy and biofuel production systems (HI, KY, NJ, NY, OK, OR and TX). Provide system-level insight into technical and economic feasibility for meeting renewable energy objectives (HI, KY, NJ, NY, OK, OR and TX). This task will incorporate outcomes of Tasks 1 and 2 toward identifying challenges and advances in regional bioenergy/biofuel production systems. This task will require integration of models developed in Tasks 1 and 2. Analysis will include feedstock availability and supply chain logistics, identification of appropriate conversion technologies and socio-political constraints for sustainability objectives. Data from Objectives A and B will be incorporated into Objective C Task 3, and results of Objective C will then inform studies in Objectives A and B. At TX this will include incorporating GIS maps for biomass sources, combining this with the optimal location of pyrolysis units, location of refineries to market products, and appropriate locations for reuse of co-products such as biochar. At NY this will include development of framework for optimal system configuration analysis. Objective D: Identify and develop needed educational, extension and outreach resources to promote the transition to a bio-based economy. Dissemination of technical information developed in Objectives A, B and C is critical for the development of biobased industries and economies. Formation of skilled workforce that is knowledgeable in biobased technology is an important component for the development and implementation of this novel economy. Task 1: Serve as a knowledge resource base for bio-based economy(All states). This regional project will serve as an information and expertise clearinghouse for biomass-related knowledge and training by interfacing with organizations involved in research and development in the bio-based economy, such as USDA, DOE, NSF, and higher education institutions. Multi-State participants will serve as expert reviewers for the BRDI post-award site-visits; the ensuing reports will be available to general public, policy makers and business leaders through existing USDA outlets. Multi-State participants will contribute to existing and future biomass-related information sites, such as the Sun-Grant Bioweb. Task 2: Develop and market programs. (AR, IL, KS, OK and SD). IL intends to continue, to offer short courses on bioprocessing of biofuel and starch production; this short course is in demand by industry. The University of Arkansas (UA), Kansas State University (KSU), Oklahoma State University (OSU) and South Dakota State University (SDSU) developed and are delivering a multi-disciplinary graduate-level on line certificate program entitled, Bioenergy Sustainability Technology (BST). At each annual meeting updates vis-a-vis BST enrolment will be presented. Emphasis will be placed on using the group to market the certificate. The academic program was developed utilizing high-quality instruction and distance delivery methods. The multi-state members are and will continue to be instrumental in updating curricula and promoting the certificate to potential students and industrial workforce. The project will continue to distribute new knowledge, and to train the work force and general public in bio-based economy. This task will continue to identify key emerging areas and audiences for which training materials will be critically needed, coordinating experts to create training materials in key areas, fostering educational collaborations between experts having complimentary expertise, organizing workshop/training on effective delivery methods for distance education, and assisting in assessment and quality assurance of biomass-related training materials. Task 3: Develop and disseminate educational materials in high-priority topic areas. The Ohio State University in collaboration with NDSU, WASU, University of Idaho (UI), and North Carolina A&T State University (NC A&T) and other multi-state partners have developed a project titled BIOBASED ENERGY EDUCATION MATERIALS EXCHANGE SYSTEM (BEEMS). This project developed and assembled a biobased energy education material exchange system for faculty members to share course materials and advocate student interaction among different institutions. Course materials such PowerPoint slides and homework exercises were developed by the team and will continue to be promoted. Faculty members who are teaching bio-based energy related courses and their students, including underrepresented groups and professionals, who have interest in continual study in bio-based energy would be impacted. It is expected that faculty members using BEEMS for their bioenergy teaching will reduce teaching preparation time by 50% via sharing of course materials. The teaching quality and student enrollment of the bioenergy related courses in the BEEMS member institutions would also be substantially increased. In addition, courses will be developed to teach professional skills of particular relevance, including effective methods for distance education, and skills for working in multidisciplinary teams. The use of distance-education technologies also will allow smaller programs to leverage resources in their training process. For instance, shared lecturing by area of expertise would enable collaborations to be conducted between experts, and expand the availability of expertise in this relatively new area. Significant milestones in the education subtask area will include recruiting experts (or teams) to develop educational materials in key areas, developing educational materials suitable for distance education, organizing peer-review assessment of educational materials, and establishing a distribution method for educational materials.
Measurement of Progress and Results
- A web site inspired by NC-213 web site will be launched. This web site will be attractive and thrive to become a go to place for biobased knowledge. The web site will could have, but are not limited to, the following homepage headings: Impacts, About us, Current News, Newsletter, Station reports, Executive Committee. The web site will be critical to disseminate developments regarding the problem of the year that the group is addressing.
- A bi-annual Newsletter will be assembled, and will highlight group achievements and activities, such as upcoming meetings, submitted scientific papers, faculty highlights, and trends in the industry. The newsletter will be critical to disseminate the barrier that the group is addressing in the calendar year.
- A large portion of the efforts outlined in Objectives A through D are application oriented and will be useful to develop pilot projects, demonstrations and commercialization of biomass conversion to biobased products.
- Other outputs include educational materials that could be used in traditional classroom settings or for distance education and web based distribution.
- Publications in peer reviewed journals, trade journals and popular magazines.
- Development of intellectual property
- Presentations to economic development groups, legislative groups, and to the general public.
Outcomes or Projected Impacts
- The committee has served and will continue to serve as a resource for: Bioresearch and Development Initiative (BRDI) (or similar program included in the 2013 Farm Bill), Biomass, Research and Development Board working groups, USDA and NSF SBIR, NSF, NIFA and DOE panels.
- The multi-state membership will contribute to the implementation of the REE energy science strategic plan.
- Multi-state membership will contribute to identification of funding priorities and shaping policy of Federal agencies.
- Research will enable reduced dependency on foreign-based fuels and chemicals.
Projected ParticipationView Appendix E: Participation
The newly designed web site will be critical to disseminate the results and information that the group has generated. The Newsletter also will be essential to synthesize and disseminate the groups progress. Tackling a yearly problem and inviting specific industry stakeholders, economists, and social scientists to present and attend the Symposium will be essential to build important leverages with industrial partners.
Research results will be made available through peer reviewed journal articles. Participants in the previous Multi-State Project S-1041 generated over 200 peer reviewed and other publications, either independently or in collaboration with other experiment stations represented by S-1041. It is expected that similar productivity will be seen in this Multi-State Project. Many articles can be accessed through individual participant web sites. Workshops and demonstrations will be organized by participating stations for feedstock production, harvesting, storage and conversion.
As for the S-1041, it is expected that this Multi-State Project will also foster scientific collaboration in terms of collaborative proposals.
Participants will meet once per year to review progress made towards attaining Objectives A, B and C. Because of the multi-disciplinary nature of this Multi-State Project, participants often meet in scientific conference settings, planning committees and in scientific review panels.
The Development Committee will use a standard form of governance using a chair, vice chair and secretary as executive officers. During annual meetings, a secretary will be elected that ascends to vice chair and chair. Terms are for one year. Subcommittees will be formed as needed during annual meetings.
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