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Ethanol is a widely-used, domestically-produced renewable fuel made from corn and other plant materials. More than 96% of gasoline sold in the United States contains ethanol. Learn more about this alternative fuel in the Ethanol Basics Fact Sheet, produced by the U.S. Department of Energy's Clean Cities program.
Executive Summary The Illinois Basin – Decatur Project (IBDP) is managed by the Midwest Geological Sequestration Consortium (MGSC) and is led by the Illinois State Geological Survey (ISGS) at the University of Illinois. The project site is located on the Archer Daniels Midland Company (ADM) property in Decatur, Illinois, and is a fully integrated carbon capture and storage (CCS) project that uses CO₂ captured from the ethanol-producing fermentation process at the ADM corn-processing plant (Finley et. al., 2013). IBDP has a goal of injecting one million tonnes of CO₂ into the basal sands of the Mt. Simon Sandstone over a three-year period. This is a multifaceted project, and this report details the planning and results of the drilling, completions, well testing, log data acquisition, and the Health, Safety, and Environment (HSE) aspects of the project. Three deep wells were planned for the IBDP: • The injection well: Injection Well #1 (CCS1); • The monitoring well (both in-zone and above seal): Verification Well #1 (VW1); and • The geophone monitoring well: Geophysical Monitoring Well #1 (GM1). The detailed plans for these wells are attached to the appendices of this document. The wells were drilled successfully with little deviation from the original plans. The biggest change from the plan to execution was the need to adjust for larger-than-expected loss of circulation in the Potosi section of the Knox Formation. The completions reports also attached to this document detail the well constructions as they were actually built. Injectivity testing was carried out, and the perforating plans were adjusted based on the results. Additional perforations and acidizing were performed as a result of the injectivity testing. The testing plans are detailed in this report along with the actual testing results. The injectivity testing results were used in the modeling and simulation efforts. Detailed HSE plans were developed and implemented during the planning and execution phases of the project. The implementation included an HSE Bridging Document, which served to unify the HSE policies of the project partners and key subcontractors. The HSE plan and actual HSE results are presented in this document. There were no recordable HSE incidents during the project. A detailed logging program was developed based on project needs. The log data were acquired in accordance with the plan, and both the plan and log results are presented in this report. Log data were heavily utilized by the research staff, modelers, reservoir engineers, and for technical and permitting efforts. 5 Several key lessons were learned during the project: • Safety in operations and execution is paramount and is only achieved through proper planning and behavior control. The certainty of this was reinforced through implementation of this lesson and the resultant flawless HSE performance during the project. • Losses of drilling fluid circulation were larger than anticipated within the Potosi Formation. Circulation was only recovered through cementing the loss zones. • When possible, minimizing complexity in permit requirements and well designs is preferable. • The size of the wells were outside of the standard experience and expertise typical within the basin, and therefore required substantial planning and ramp-up of contractors and partners to meet project objectives. • With multiple stakeholders and research partners, establishing objectives and requirements early and adhering to change request procedures throughout the project are critical to manage competing data and sampling objectives that may be detrimental to overall progress. The well construction and completion operations were successfully executed, with all wells built in a manner that achieved excellent wellbore integrity. Log planning involved a number of stakeholders and technical specialists. Data collection from logging, coring, and testing was excellent. Time and effort spent with the associated contractors and suppliers to develop a well plan beyond normal scope proved highly successful, resulting in a well-construction and completion project that surpassed expectations. The world-class HSE results also demonstrate the commitment of all stakeholders in the project. The details follow in the body of this document
One viable treatment method for conversion of lignocellulosic biomass to biofuels begins with saccharification (thermochemical pretreatment and enzymatic hydrolysis), followed by fermentation or catalytic upgrading to fuels such as ethanol, butanol, or other hydrocarbons. The post-hydrolysis slurry is typically 4-8 percent insoluble solids, predominantly consisting of lignin. Suspended solids are known to inhibit fermentation as well as poison catalysts and obstruct flow in catalyst beds. Thus a solid-liquid separation following enzymatic hydrolysis would be highly favorable for process economics, however the material is not easily separated by filtration or gravimetric methods. Use of a polyacrylamide flocculant to bind the suspended particles in a corn stover hydrolyzate slurry into larger flocs (1-2mm diameter) has been found to be extremely helpful in improving separation. Recent and ongoing research on novel pretreatment methods yields hydrolyzate material with diverse characteristics. Therefore, we need a thorough understanding of rapid and successful flocculation design in order to quickly achieve process design goals. In this study potential indicators of flocculation performance were investigated in order to develop a rapid analysis method for flocculation procedure in the context of a novel hydrolyzate material. Flocculation conditions were optimized on flocculant type and loading, pH, and mixing time. Filtration flux of the hydrolyzate slurry was improved 170-fold using a cationic polyacrylamide flocculant with a dosing of approximately 22 mg flocculant/g insoluble solids at an approximate pH of 3. With cake washing, sugar recovery exceeded 90 percent with asymptotic yield at 15 L wash water/kg insoluble solids.
The cellulosome system contributes greatly to the extreme efficiency of C. thermocellum cellulose degradation. In order to further understand the cellulosome working mechanism, we have knocked out C. thermocellum scaffoldin genes to generate a variety of deletion mutants. The knockout most detrimental to enzymatic hydrolysis by the secretome is that of the primary scaffoldin CipA. Deletion of multiple secondary scaffoldins results in secretome activities intermediate between those of the parent strain and the CipA-knockout mutants. The order of relative secretome activities is the same, whether the cellulosic substrate is microcrystalline cellulose (Avicel) or deacetylated acid-pretreated corn stover (DACS), but the relative magnitudes of the deletion effects are strongly substrate-dependent. Similar trends are observed in fermentation studies of the abilities of the parent and knockout strains themselves to utilize Avicel and DACS. Data from transcriptomic and proteomic studies of these strains when grown on both substrates are used to relate the activity and growth effects of the deletions to their effects on the overall expression of lignocellulose-degrading enzymes by C. thermocellum.
Xylan constitutes a significant portion of biomass (e.g. 22% in corn stover used in this study). Xylan is also an important source of carbohydrates, besides cellulose, for renewable and sustainable energy applications. Currently used method for the localization of xylan in biomass is to use fluorescence confocal microscope to image the fluorescent dye labeled monoclonal antibody that specifically binds to xylan. With the rapid adoption of the Raman-based label-free chemical imaging techniques in biology, identifying Raman bands that are unique to xylan would be critical for the implementation of the above label-free techniques for in situ xylan imaging. Unlike lignin and cellulose that have long be assigned fingerprint Raman bands, specific Raman bands for xylan remain unclear. The major challenge is the cellulose in plant cell wall, which has chemical units highly similar to that of xylan. Here we report using xylanase to specifically remove xylan from feedstock. Under various degree of xylan removal, with minimum impact to other major cell wall components, i.e. lignin and cellulose, we have identified Raman bands that could be further tested for chemical imaging of xylan in biomass in situ.
PHAs are synthesized by many microorganisms to serve as intracellular carbon storage molecules. In some bacterial strains, PHB can account for up to 80% of cell mass. In addition to its application in the packaging sector, PHB also has great potential as an intermediate in the production of hydrocarbon fuels. PHB can be thermally depolymerized and decarboxylated to propene which can be upgraded to hydrocarbon fuels via commercial oligomerization technologies. In recent years a great effort has been made in bacterial production of PHB, yet the production cost of the polymer is still much higher than conventional petrochemical plastics. The high cost of PHB is because the cost of the substrates can account for as much as half of the total product cost in large scale fermentation. Thus searching for cheaper and better substrates is very necessary for PHB production. In this study, we demonstrate production of PHB by Cupriavidus necator from a process relevant lignocellulosic derived sugar stream, i.e., saccharified hydrolysate slurry from pretreated corn stover. Good cell growth was observed on slurry saccharified with advanced enzymes and 40~60% of PHB was accumulated in the cells. The mechanism of inhibition in the toxic hydrolysate generated by pretreatment and saccharification of biomass, will be discussed.
Objective of the presentation is to document land use and water use implications of biomass production to demonstrate the overall resources implications associated with bioethanol production for Florida’s transportation sector needs. Rationale for using biofuels (BF) is explained, so are advantages & challenges of BF production and use. Land use changes (LUC) in Florida are presented and consequences outlined. It is documented that Florida’s agricultural land is a very limited resource, with only 0.43 ac/person comparing to the global average of 1.71 ac/person. The direct relation of increased biofuels production causing increased water use is explained. Favorable climate, water resources, advanced research, traditional leading agricultural role, minor oil reserves, no refineries and increasing energy demands are the main reasons why Florida considers pursuing BF production in large scale. Eight various bioethanol crops produced in Florida were considered in this study (Miscanthus, Switchgrass, Sweet Sorghum, Corn, Elephantgrass, Sugarcane, Energycane, Eucalyptus). Biomass yield and bioethanol yield of these crops are documented. Bioethanol needs of Florida are estimated and related land requirements for the needed bioethanol production calculated. Projections for various bioethanol blends (E15 to E85) are then presented. Finally, water demand for biofuels production is quantified. It is concluded that land use requirement for production of all ethanol in E85 fuel blend in Florida is roughly the same as the total available ag land in Florida for the best yielding biofuels crops (energycane, eucalyptus). Water demand for production of all ethanol needed for E100 would increase current overall water consumption in Florida between 65% and 100% for the most common biofuels crops. Vehicular energy is only 33% of Floridians energy consumption, so even all Florida’s agricultural land was given up for biofuels, it would still produce only 33% of Florida’s total energy needs. Still, bioethanol (primarily cellulosic) produced in Florida has a potential to meet a significant portion of the State’s transportation needs. Assuming no change in food production and consumption habits in Florida, the likely result of biofuels sector expansion would be the conversion of natural lands or low-intensity agricultural lands into high-intensity biomass production and the associated increased water consumption and water quality implications.
In order to increase the sustainability and security of the nation’s energy supply, the U.S. Department of Energy through its Bioenergy Technology Office has set a vision for one billion tons of biomass to be processed for renewable energy and bioproducts annually by the year 2030. The Renewable Fuels Standard limits the amount of corn grain that can be used in ethanol conversion sold in the U.S, which is already at its maximum. Therefore making the DOE’s vision a reality requires significant growth in the advanced biofuels industry where currently three cellulosic biorefineries convert cellulosic biomass to ethanol. Risk mitigation is central to growing the industry beyond its infancy to a level necessary to achieve the DOE vision. This paper focuses on reducing the supply risk that faces a firm that owns a cellulosic biorefinery. It uses risk theory and simulation modeling to build a risk assessment model based on causal relationships of underlying, uncertain, supply driving variables. Using the model the paper quantifies supply risk reduction achieved by converting the supply chain from a conventional supply system (bales and trucks) to an advanced supply system (depots, pellets, and trains). Results imply that the advanced supply system reduces supply system risk, defined as the probability of a unit cost overrun, from 83% in the conventional system to 4% in the advanced system. Reducing cost risk in this nascent industry improves the odds of realizing desired growth.
The polymers found in plant cell walls represent the largest reserves of renewable carbon on Earth - it has been estimated that the United States has approximately 1.3 billion tons of plant biomass available per year. Ionic liquids (ILs) are salts with melting points less than 100oC, typically containing organic cations, that possess a wide range of extraordinary properties as compared to traditional organic solvents. The unusual catalytic and solvation properties of ionic liquids have attracted the biofuel and biomass communities because IL-pretreatment provides higher fermentable sugar yields than those obtained by acid- or alkali-pretreatment under similar severities. This research used lignin, a major by-product of the biofuel and pulping industries, as raw material for IL synthesis. The goal is to lower the cost of IL production, and enable a more "closed-loop" biorefinery. The lignin is oxidatively depolymerized, purified, and used to prepare a new class of renewable ILs. Biomass pretreatment was the target application for the lignin-derived ILs, while we continue to investigate additional applications within the growing IL market - process chemistry, biotechnology and materials recycling. When comparing our corn stover pretreatment data to recently published reports, we have shown comparable glucose and xylose yields by using neat and 10% aqueous solutions of lignin-derived ILs.
Biomass feedstock production is expected to grow as demand for biofuels and bioenergy increases. The change in air pollutant emissions that may result from large-scale biomass supply has implications for local air quality and human health. We developed spatially explicit emissions inventories for corn grain and six cellulosic feedstocks through the extension of the National Renewable Energy Laboratory's Feedstock Production Emissions to Air Model (FPEAM). These inventories include emissions of seven pollutants (nitrogen oxides, ammonia, volatile organic compounds, particulate matter, sulfur oxides, and carbon monoxide) generated from biomass establishment, maintenance, harvest, transportation, and biofuel preprocessing activities. By integrating the EPA's MOtor Vehicle Emissions Simulator (MOVES) into FPEAM, we created a scalable framework to execute county-level runs of the MOVES-Onroad model for representative counties (i.e., those counties with the largest amount of cellulosic feedstock production in each state) on a national scale. We used these results to estimate emissions from the on-road transportation of biomass and combined them with county-level runs of the MOVES-Nonroad model to estimate emissions from agricultural equipment. We also incorporated documented emission factors to estimate emissions from chemical application and the operation of drying equipment for feedstock processing, and used methods developed by the EPA and the California Air Resources Board to estimate fugitive dust emissions. The model developed here could be applied to custom equipment budgets and is extensible to accommodate additional feedstocks and pollutants. Future work will also extend this model to analyze spatial boundaries beyond the county-scale (e.g., regional or sub-county levels).
There is significant global interest in developing, testing, and using alternative jet fuels for both commercial and military use in an effort to create a sustainable and stable fuel supply while reducing greenhouse gas emissions. Currently, the aviation industry is entirely dependent on a finite-supply of petroleum based fuel sourced in part by politically and economically unstable regions of the world. Commercial jet fuel use within the contiguous United States (CONUS) was 17.8 billion gallons per year (BGY) in 2009, while jet fuel use in 2010 by the U.S. Air Force (USAF), Navy, and Army was 1.5 BGY, 0.6 BGY, and 0.8 BGY, respectively (Carter et al., 2011). U.S. commercial and military aviation sectors have set ambitious near-term alternative fuel and environmental performance targets. This includes a tentative Federal Aviation Administration (FAA) goal of 1 BGY alternative fuel use by commercial aircraft by 2018. The USAF has set a target of 50% for USAF domestic aviation via alternative fuels by 2016 (0.73 BGY), and 50% of the Navy’s total energy consumption afloat (0.3 BGY) will come from alternative fuels by 2020 (Carter et al., 2011). If these targets become policy, at least 2 BGY of domestically-produced alternative jet fuel will be required by 2020. The Energy Independence and Security Act (EISA) of 2007 established production requirements for domestic alternative fuels under the Renewable Fuel Standard (RFS). For example, 36 billion gallons of renewable fuel must be produced by 2022, of which 21 billion gallons shall be advanced biofuels. EISA defines advanced biofuels as non-corn starch derived biofuels having lifecycle greenhouse gas emissions 50% lower than gasoline. There a number of potential fuel pathways for meeting the RFS. One of these is biomass-based diesel, including jet fuel (Schnepf and Yacobucci, 2013). The U.S. Department of Energy (DOE) Bioenergy Technologies Office (BETO) has a stated goal in its 2013 Multi-Year Program Plan (USDOE, 2013) to support the RFS through development of “…commercially viable biomass utilization technologies to encourage the creation of a new domestic bioenergy industry…”. BETO has also recognized the potential for aviation biofuels to support the bioenergy industry, seeing drop-in bio-based jet fuels one of the viable alternatives for the aviation industry and the military to meet their ambitious near-term GHG reduction targets (USDOE, 2014). One of the important Multi-year Program Plan Targets (USDOE, 2013) is to establish feedstock resource assessment models to evaluate the geographic, economic, quality and environmental criteria for which 20 million metric tons of ash free dry weight (AFDW) algal biomass can be produced by 2022. Toward meeting the EISA requirements, algal biofuels may offer a number of advantages. They can produce a range of biofuel feedstocks suitable for diesel and aviation fuels. Microalgae, on a strain-specific basis, can be cultivated using impaired water including saline, and/or brackish pumped groundwater or seawater, treated industrial wastewater, municipal sewage effluent, and produced water generated from oil and gas drilling operations. Additionally, microalgae require nitrogen and phosphates as essential nutrients and could provide water treatment co-benefits to municipalities, industry, and the environment.
Not all biomass is created equal, and the low quality of many sources of biomass precludes their use in many conversion processes. As we work to achieve the Billion Ton vision, more of these low quality biomass sources will need to be integrated into the feedstock supply chain and their quality issues must be dealt with to make them usable. Many of these feedstocks suffer from elevated concentrations of ash, which can interfere with thermochemical conversion reactions, catalysts, and conversion products. In this study, the cost of incremental reductions in ash concentrations was investigated in three potential biomass feedstocks: logging residues, corn stover, and construction and demolition waste. Air classification (AC) is a mechanical separations method that has been shown to concentrate ash into the lighter fractions, and ash content can be decreased by discarding these fractions. However, the cost of disposal and replacement of the discarded fraction make this strategy unaffordable (= $11.04 ton-1). Alternatively, the lightest AC fraction can be acid-leached to remove ash and recombined with the remainder of the sample. Using this approach, ash content can be decreased in logging residues from 1.1% to 0.83% for $1.95 ton-1. Ash concentrations could be further decreased with the combined strategy to 0.67% (a 40% reduction) for $3.88 per ton. This approach costs between $0.07 and $0.10 percent-1 ton-1 for the removal of up to 40% of the ash in the feedstock. This separate-treat-recombine method is an effective way to introduce lower quality feedstocks into the biomass feedstock supply chain.
One essential prerequisite for achieving design throughput and product conversion yield of cellulosic biofuel in commercial operation is a robust biomass feedstock preprocessing system. Such a system will reliably and steadily supply consistent quality feedstock to the conversion reactor. Pioneer cellulosic biofuel plants have encountered many feedstock handling challenges which lead to lengthy startup and difficulties in meeting plant nameplate production rate. Most of the biomass material handling challenges are caused by: (1) variability in biomass properties especially for herbaceous materials such as corn stover, (2) inadequate integrated testing of equipment, (3) not using the appropriate equipment or equipment design for the job, (4) mismatching of equipment capacity and turn down ratio, (5) lack of integrated control for the whole feedstock preprocessing system, and (6) inadequate surge capacity. This presentation will discuss the feedstock preprocessing challenges, identify key areas from equipment design and operation to process integration requiring optimization or further development to achieve robust integrated biomass feedstock preprocessing systems.
In humans and other mammals, it is our bones that give form to our bodies and enable our muscles to exert force. Insects have a hard exoskeleton for the same reason. But plants—from flowers to trees—are different. Their structure comes from bundles of cellulose biomolecules that form microfibers, which combined with other materials including lignin make up the walls of plant cells. These walls are so strong that they essentially act as a skeleton. Indeed, cellulose-rich cell walls enable a slender stalk of corn to grow 6 or 8 feet tall and a giant Sequoia to tower more than 300 feet, dwarfing any other life form. Cellulose is the most abundant (and arguably the most important) long-chain biomolecule on earth. Until recently, however, cellulose—both its structure and how plants make it—was a mystery. That’s why the U.S. Department of Energy’s Office of Science funded an Energy Frontier Research Center (EFRC) to explore the topic and its implications for advanced plant-based materials and biofuels. The Center for Lignocellulose Structure and Formation included a dozen principal investigators spread across a number of universities, including physicists and engineers as well as plant biologists.
The U.S. Department of Energy Bioenergy Technologies Office (BETO) is committed to the development of sustainable, nationwide, commercial biofuel production to displace petroleum-derived fuels, increase domestic energy production, and encourage the creation of a domestic bioenergy and bioproducts industry. Operating a commercial-scale bioenergy operation requires significant technological advancements for determining biomass feedstock quality during the preprocessing stage. Usage of non-food feedstocks- e.g., corn-stover, pine residue, and forest residue - at the biorefineries reduces strain on the food supply chain. But the non-food feedstock heterogeneity- physical size, shape, and chemical composition-poses a significant challenge during milling, conveyance, feeding, and biofuel conversion processes. 3D X-Ray imaging (CT) is capable of distinguishing material features by detecting density and compositional differences. But the inherent complexity introduced during harvesting and bailing makes the reconstruction and interpretation of baled biomass materials from x-ray data time consuming, laborious, and expensive. Feedstocks are low-density materials that produce small contrast differences in the x-ray images. This paper focuses on using the shape and texture properties, using 3D image processing techniques like 3D skeletonization, directional statistics to characterize and extract volumetric content of the different tissue samples in the biomass bales.
The Biological Upgrading of Sugars (BUS) project directly targets the anaerobic conversion of lignocellulosic feedstocks into intermediate molecules readily upgradeable to fuel precursors. Recent efforts on the BUS project have a particular emphasis on the biological production of butyric acid, an intermediate that can be readily upgraded to sustainable aviation fuel, diesel blend-stocks, and high value chemicals. The BUS project approaches this direction through a combination of strain engineering, fermentation process engineering, development of novel separations technologies, and the design and build of pilot scale systems. Our ultimate project goal is to develop an integrated cost-effective process at pilot scale to achieve DOE's MYPP targets of $2.50/GGE. The major thrust of the BUS project over the last project cycle was on the development of integrated processes surrounding the anaerobic production of carboxylic acids using diverse Clostridium species. We developed and expanded genetic tools for several Clostridium species and rewired microbial metabolism in an attempt to maximize substrate utilization and flux towards butyric acid. We designed and built novel bioreactors with an in situ product recovery system enabling the biological production and recovery of highly purified acids. We leveraged this system to generate 100s of grams of acid from corn stover hydrolysate. In this presentation we highlight data surrounding our proposed process and accompanying results from technoeconomic and life-cycle analyses of our integrated process. Finally, we detail plans of our pilot scale reactor system that is in process and discuss our future routes towards achieving economically viable and sustainable diesel and jet blendstocks.
Production of aromatic aldehydes, such as vanillin, from lignin, has been an intriguing process for decades, but widespread implementation has been inhibited by the high hydroxide:lignin ratios required for significant aldehyde yields. In this work, we explore oxidation of lignin-rich residues isolated from corn stover after deacetylation, mechanical refining, and enzymatic hydrolysis (DMR lignin), using reversibly-soluble bases in place of NaOH. In particular, strontium and barium hydroxides have low solubility at room temperature, but become soluble to more than 2 M at temperatures above 100 °C, thus producing highly alkaline conditions at reaction temperature but facilitating a simple recovery and recycle of the alkali upon cooling. Aromatic monomer yields are comparable for both types of bases at 20-30 wt%, depending on the lignin substrate. Overall, these results suggest a strategy to substantially reduce the cost and life cycle impact of lignin depolymerization by alkaline oxidation.
Moving toward a circular carbon economy requires enabling reuse of carbon-based macromolecules like those in biomass and polymers. Meeting this goal requires increased upcycling of waste products into higher value products. For biomass waste such as corn stover, pine needles, or bark, one approach is using pyrolysis to convert these feedstocks into bio-oil that can be used for liquid fuel or transformed into other hydrocarbon based products, like bio-polymers. Waste plastics can be upcycled or recycled into new products, or alternatively converted into bio-oil by pyrolysis. Macromolecules from biomass and polymers are challenging to convert into liquid fuel or chemical feedstocks, due to large and sometimes heterogeneous networks of polymeric bonds. We work with the Idaho National Laboratory’s Biomass Feedstock National User Facility and Department of Energy’s Feedstock Conversion Interface Consortium to develop a molecular understanding of biomass variability that occurs naturally and as a result of storage or preprocessing techniques applied to feedstocks, to understand chemical reactions occurring during pyrolysis and other biomass or polymer conversion techniques. Using two dimensional gas chromatography mass spectrometry coupled to analytical pyrolysis provides insight into the molecular changes that occur during the pyrolysis event, and these insights can extend to bench or pilot scale pyrolysis conversions. Understanding pyrolysis of biomass and polymers at a molecular level contributes to development of new tools to predict and manipulate the optimum conditions and identify the best storage, preprocessing, and conversion techniques to maximize output of specific high-value chemical species in the conversion to fuels, or to characterize feedstocks for blending before pyrolysis. Identification and understanding of the molecular level changes resulting from novel preprocessing techniques that can be used to control and manipulate the chemical output of bench or pilot scale pyrolysis is another focus of investigation, including the use of gamma irradiation, acid, or enzyme pre-treatments. We also focus on the impacts of storage conditions and techniques, which can affect moisture levels, degradation, and impacts from naturally occurring microbes in the environment.
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