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At least 109 records · Page 6
All sourcesNASA NTRSDOE OSTI
DOE OSTI2026

Feedstock Choices for Advancing the Bioeconomy in the US and Policy Implications

Biomass feedstocks will be critical for scaling up the bioeconomy in the United States to meet multiple demands for biofuels, sustainable aviation fuel, bioproducts, and biochemicals. There is a wide range of choices of feedstocks, including a variety of dedicated energy crops and crop residues. There are substantial differences in the yields, costs of production, and carbon intensity of these feedstocks and for each feedstock across locations. These feedstocks also differ in the trade-offs they offer among multiple environmental impacts. We discuss the economic factors that will influence the production of these feedstocks and the implications of alternative biofuel and low-carbon policies for the mix of feedstocks that will be incentivized.

Khanna, Madhu (ORCID:0000000349944451)↗
DOE OSTI2019

Effect of Powder Shape and Size on Rheological, Thermal, and Segregation Properties of Low-Pressure Powder Injection Molding Feedstocks

Optimization of molding parameters at different filling stages requires that the characteristics of low-viscosity feedstocks must be properly known. In this study, the influence of the particle size (3, 7, and 12 μm) and powder morphology (gas- and water-atomized) was quantified using different feedstock formulations based on a 17-4 PH stainless steel powder, all combined with the same binder system. The specific heat capacity, viscosity, and segregation levels were assessed using a differential scanning calorimeter, a rotational rheometer, and a thermogravimetric analyzer, respectively. It was then shown that the feedstock prepared with the gas-atomized powder exhibits a higher specific heat capacity value when compared to a water-atomized powder (i.e., Cp varying from 0.6 to 0.3 J/g K, respectively). It was also shown that the feedstock viscosity profiles and the intensity of segregation both depend significantly on the powder shape and size used in the feedstock formulation. For short processing times (e.g., < 1 min spent in molten state), a feedstock formulated with coarse gas-atomized powder can be considered to be the best candidate for an injection process because its viscosity and segregation potential are relatively low (with a viscosity varying from 0.5 to 2 Pa s, and a volume fraction of powder close to 60 vol.%). Following this, the moldability index was used to predict that coarser water-atomized powder (i.e., 12 versus 7 μm) will not have a significant effect on the molding properties, and can be seen as a potential means of decreasing shrinkage during sintering without impacting the injection properties. For very long processing times, the magnitude of segregation remains insignificant for feedstock formulated with fine powder (i.e., a volume fraction of powder remaining close to 60 vol.%). However, this important gain (i.e., no segregation) comes with a significant increase in viscosity varying from 2 to 10 Pa s, resulting in a decrease in the molding properties.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Biomanufacturing from gaseous C1 feedstocks: A perspective on opportunities and challenges

Single-carbon (C1) substrates including carbon dioxide, carbon monoxide, and methane are abundantly available from natural and anthropogenic sources and present potential feedstocks for biomanufacturing. Utilizing these C1 gas feedstocks in bioprocesses for sustainable production of chemicals and fuels could prove pivotal in removing excess carbon from the atmosphere. This perspective describes the spectrum and sources of CO2, CO, and CH4 and examines emerging opportunities in microbial bioconversion and bioelectrochemical processes for these feedstocks. We discuss existing challenges in bioprocess development that currently restrict the commercialization of C1 biomanufacturing technologies. We detail different aerobic and anaerobic bioconversion approaches for C1 feedstocks employing pure and mixed cultures and examine the suitability of each scenario for producing specific molecules. Beyond strain engineering and bioprocess constraints, we address often overlooked factors that limit the development of efficient and reliable bioprocesses, including technology availability for research and safety considerations. We then discuss and recommend the necessary safety features and technological research tools for developing fast, safe, and efficient bioprocesses using gaseous feedstocks to support the scale-up and commercialization of C1 biomanufacturing technologies. This perspective provides an overview of the current scientific and industrial state of the art and offers insights into future technological needs that must be addressed to realize the potential of biomanufacturing from gaseous feedstocks. Synopsis: C1 gases offer a sustainable feedstock for biomanufacturing of fuels and chemicals. This work analyzes bioconversion methods, challenges, and safety considerations, and emphasizes the need for improved technology to enable commercialization.

Biomanufacturing↗
DOE OSTI2021

Varied farm-level carbon intensities of corn feedstock help reduce corn ethanol greenhouse gas emissions

Abstract A reduction in the overall carbon intensity (CI) of a crop-based biofuel can be achieved by cutting down the CI of the biofuel’s feedstock, which in turn correlates significantly to agricultural management practices. Proposals are being made to incentivize low-carbon biofuel feedstocks under U.S. fuel regulatory programs to promote sustainable farming practices by individual farms. For such an incentive scheme to function properly, robust data collection and verification are needed at the farm level. This study presents our collaboration with U.S. private sector companies to collect and verify the corn production data necessary for feedstock-specific CI calculation at the farm level, through a carefully designed questionnaire, to demonstrate the practicality and feasibility of data collection at scale. We surveyed 71 farms that produced 0.2 million metric tons of corn grain in 2018 in a Midwestern U.S. state to obtain information on key parameters affecting corn ethanol feedstock CI, such as grain yields, fertilizer/chemical application rates, and agronomic practices. Feedstock-specific CI was calculated in the unit of grams (g) CO 2 equivalent (CO 2 e) of greenhouse gases per kilogram (kg) of corn produced. Results showed large CI variations—from 119 to 407 g CO 2 e kg −1 of corn—due to the farm-level inventory, while the production-weighted average CI for all surveyed farms was 210 g CO 2 e kg −1 , comparable to the national average CI of 204 g CO 2 e kg −1 . The nitrogen fertilizer type applied and rate were identified as key factors contributing most to CI variations at the farm level. The estimated N 2 O emissions from fertilizer and biomass nitrogen inputs to soil accounted for 51% of the overall farm-level CI and therefore need to be better monitored at farm level with high resolution. We concluded that this feedstock-specific, farm-level CI evaluation has the potential to be used to incentivize low-carbon feedstock for biofuel production.

54 ENVIRONMENTAL SCIENCES↗
NASA NTRS2005

Synthesizing Diamond from Liquid Feedstock

A relatively economical method of chemical vapor deposition (CVD) has been developed for synthesizing diamond crystals and films. Unlike prior CVD methods for synthesizing diamond, this method does not require precisely proportioned flows of compressed gas feedstocks or the use of electrical discharges to decompose the feedstocks to obtain free radicals needed for deposition chemical reactions. Instead, the feedstocks used in this method are mixtures of common organic liquids that can be prepared in advance, and decomposition of feedstock vapors is effected simply by heating. The feedstock used in this method is a solution comprising between 90 and 99 weight percent of methanol and the balance of one or more other oxyhydrocarbons that could include ethanol, isopropanol, and/or acetone. This mixture of compounds is chosen so that dissociation of molecules results in the desired proportions of carbon-containing radicals (principally, CH3) and of OH, H, and O radicals. Undesirably, the CVD temperature and pressure conditions thermodynamically favor the growth of graphite over the growth of diamond. The H radicals are desirable because they help to stabilize the growing surface of diamond by shifting the thermodynamic balance toward favoring the growth of diamond. The OH and O radicals are desirable because they preferentially etch graphite and other non-diamond carbon, thereby helping to ensure the net deposition of pure diamond. The non-methanol compounds are included in the solution because (1) methanol contains equal numbers of C and O atoms; (2) an excess of C over O is needed to obtain net deposition of diamond; and (3) the non-methanol molecules contain multiple carbon atoms for each oxygen atom and thus supply the needed excess carbon A typical apparatus used in this method includes a reservoir containing the feedstock liquid and a partially evacuated stainless-steel reaction chamber. The reservoir is connected to the chamber via tubing and a needle valve or other suitable flow controller. When the liquid enters the low-pressure environment inside the chamber, it evaporates to form a vapor mixture of the same chemical composition. In addition to the inlet for the feedstock liquid, the chamber is fitted with an outlet connected to a vacuum pump (not shown) through a throttle valve (also not shown) that is automatically controlled to keep the pressure at or near the required value throughout the deposition process. Inside the chamber, a spiral filament made of tungsten, tantalum, graphite, or other high-melting-temperature material is electrically heated to a temperature >2,000 C high enough to cause dissociation of vapor molecules into the aforementioned radicals. A deposition substrate typically, a diamond-polished silicon wafer about 2.5 cm square is positioned about 2 cm away from the filament. The exact location of the substrate is chosen so that the substrate becomes heated by the filament to a deposition temperature in the approximate range of 800 to 1,000 C.

Tzeng, Yonhua↗
DOE OSTI2015

Method and apparatus for treating a cellulosic feedstock

Methods and apparatus for treating, pre-treating, preparing and conveying a cellulosic feedstock, such as for ethanol production, are disclosed. More specifically, the invention relates to methods and apparatus for treating a cellulosic feedstock by mixing and heating the cellulosic feedstock and/or by moistening and heating the cellulosic feedstock. The invention also relates to a holding tank, and a method of utilizing the holding tank whereby bridging may be reduced or eliminated and may result in a product stream from autohydrolysis or hydrolysis having an improved yield. The invention further relates to methods and apparatus for obtaining and conveying a cellulosic feedstock, which may be used for the subsequent production of a fermentable sugar stream from the cellulose and hemicellulose in the cellulosic feedstock wherein the fermentable sugar stream may be used for subsequent ethanol production. The invention also relates to a method and apparatus for withdrawing one or more feedstock stream from a holding tank.

09 BIOMASS FUELS↗
DOE OSTI2018

Assessing Potential Air Pollutant Emissions from Agricultural Feedstock Production using MOVES

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).

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2025

Distillable amine-based solvents for effective pretreatment of multiple biomass feedstocks

Exploring the potential of advanced distillable solvents as efficient biomass pretreatment agents is critical for biorefineries, enhancing fermentable sugar yields while enabling solvent recovery and recycling without suffering significant losses. Here, we employ distillable amine-based solvents for pretreating a wide range of lignocellulosic feedstocks, aiming to facilitate the industrial release of fermentable sugars from diverse feedstocks through enzymatic hydrolysis. Twenty-two diverse feedstocks, sourced from different geographical regions and representing various biomass categories, were surveyed for chemical (mainly carbohydrates and lignin) and lignin (S, G, and H units) profiles. Several solvents, including ethanolamine, ethanolammonium acetate, butylamine, butylammonium acetate, and triethylamine, were tested for the pretreatment of eight selected biomasses. Among these solvents, butylamine emerged as the most effective due to its favorable sugar release, excellent solvent removal rate, and low boiling point, facilitating solvent recovery and recycling. Extending butylamine pretreatment to all 22 feedstocks demonstrated desirable sugar yields and highly efficient solvent removal in the majority of the biomass sources tested. Agricultural residues and their mixtures showed particularly favorable sugar release. Despite minimal changes in cellulose crystallinity, XRD characterization of sorghum, poplar, and pine before and after butylamine pretreatment showed a decrease in intensity and a slight shift of certain peaks, indicating alterations in cellulose structure. Fourier-transform infrared spectroscopy and thermogravimetric analysis analyses suggested disruption of biomass linkages in hemicellulose and lignin, enhancing enzymatic digestibility. Scale-up experiments of the mixed agricultural feedstocks in a 1 L Parr reactor achieved over 90% glucose liberation and more than 99% butylamine removal, highlighting the scalability of the method. The resulting hydrolysates supported the growth of diverse bacterial and fungal strains, indicating downstream compatibility with commercial fermentation processes. This study presents butylamine as an effective, recoverable pretreatment solvent for a wide range of lignocellulosic feedstocks, offering a promising solution to key biorefinery challenges. The demonstrated scalability and compatibility with various biomass types and blends underscore its potential for industrial application, advancing sustainable biofuel and biochemical production.

biomass composition↗
DOE OSTI2020

Woody Feedstocks 2019 State of Technology Report

The U.S. Department of Energy promotes production of advanced liquid transportation fuels from lignocellulosic biomass by funding fundamental and applied research that advances the state of technology (SOT). As part of its involvement with this overall mission, Idaho National Laboratory completes annual SOT reports for nth-plant biomass feedstock logistics. The purpose of the SOTs is to provide the status of feedstock supply system technology development for biomass to biofuels, based on actual data and experimental results relative to technical targets and cost goals from specific design cases. The 2019 Woody Feedstock SOT presents the State of Technology for feedstock supply to three individual thermochemical conversion pathways that utilize woody feedstocks: Indirect Liquefaction (IDL), Catalytic Fast Pyrolysis (CFP), and Algal-blend Hydrothermal liquefaction (AHTL). The 2019 reactor throat delivered feedstock costs were found to be $63.54/dry ton, $70.15/dry ton and $70.31/dry ton, respectively (2016$).

09 BIOMASS FUELS↗
DOE OSTI2017

Biomass Blending and Densification: Impacts on Feedstock Supply and Biochemical Conversion Performance

The success of lignocellulosic biofuels and biochemical industries depends on an economic and reliable supply of high-quality biomass. Many research and development efforts, however, have been historically focused on the utilization of agriculturally derived cellulosic feedstocks, without considerations of their low energy density, high variations in compositions and potential supply risks in terms of availability and affordability. This book chapter demonstrated a strategy of feedstock blending and densification to address the supply chain challenges. Blending takes advantage of low cost feedstock to avoid the prohibitive costs incurred through reliance on a single feedstock resource while densification produces feedstocks with increased bulk density and desirable feed handling properties as well as reduced transportation cost. We also review recent research on the blending and densification dealing with various types of feedstocks with a focus on the impacts of these preprocessing steps on biochemical conversion, i.e., various thermochemical pretreatment chemistries and enzymatic hydrolysis, into fermentable sugars for biofuel production.

09 BIOMASS FUELS↗
DOE OSTI2018

The cost of improved quality feedstocks: How good is "good enough"?

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.

09 BIOMASS FUELS↗
DOE OSTI2018

Key factors in designing a robust biorefinery feedstock preprocessing system

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.

09 BIOMASS FUELS↗
DOE OSTI2025

Synthetic microbial communities: Bridging research and application in second-generation bioenergy feedstock microbiomes

The sustainable production of purpose-grown bioenergy feedstocks is essential in transitioning away from fossil fuels. Synthetic communities (SynComs) are consortia of microorganisms that can be used as biological interventions to support objectives like plant growth and stress tolerance. This review examines the state of knowledge regarding microbiomes and SynComs of second-generation bioenergy feedstocks, focusing on the rhizosphere. We first provide an overview of second-generation feedstocks, including switchgrass (Panicum virgatum), miscanthus (Miscanthus × giganteus), sorghum (Sorghum spp.), sugarcane (Saccharum spp.), and poplar (Populus spp.), and summarize our current understanding of their plant-soil-microbiome ecology. We next discuss considerations in the objectives, design, and evaluation of SynComs to enhance feedstock production, and then critically review the literature around their use. Our literature analysis revealed that SynCom performance varied substantially between controlled pilot experiments and field trials, possibly due to system complexity that could not be fully considered in their design and pilot evaluation. We identified a gap in the use of SynComs to support the unique sustainability objectives of biofuel feedstock agriculture, presenting an opportunity to leverage these additional microbial traits in SynCom designs. Finally, we emphasize the importance of targeted research to identify the ecological principles that govern the assembly, activation, and persistence of microbes in the feedstock rhizosphere, thereby enhancing our capacity to manage microbiomes under diverse environmental conditions and ensure their functionality. Beyond biofuels, SynComs are a promising microbiome management strategy for crop production; however, an ecologically informed design and evaluation of SynComs are advised.

SynCom↗
DOE OSTI2020

Production of mechanically-generated 316L stainless steel feedstock and its performance in directed energy deposition processing as compared to gas-atomized powder

The objective of this work is to study the feasibility of mechanically-generated feedstock for use in directed energy deposition (DED) processing. Mechanically-generated powder was created by machining 316L stainless steel bar stock followed by comminution of the resulting chips through oscillation ball milling. This methodology's production yield and processing time for the specifications of a commercially available DED system are presented along with resulting powder morphology. Performance of the mechanically-generated feedstock was compared to gas-atomized powder and evaluated based on the following figures of merit: flowability, printed part height, printed part density, and chemical compositional stability throughout processing. Mechanically-generated feedstock was created to meet deposition system requirements. Compared with gas-atomized powder, mechanically-generated powder did not flow as well through the powder-delivery system. Parts printed from mechanically-generated feedstock were generally taller than their counterparts from gas-atomized feedstock, but their densities were less predictable. As a result, chemical composition of prints using both feedstocks was within standard nominal compositions for 316L stainless steel.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Utilization of Wet Forest Biomass as both the Feedstock and Electricity Source for an Integrated Biochar Production System

Abstract. A belt dryer and gasifier generator set were integrated into a biochar production plant to use process heat to dry biomass feedstock from forest residuals and to provide electric power to the plant using a side stream of dried biomass. Experiments were conducted to characterize the dryer throughput and drying capacity using process heat from a stack heat exchanger attached to the biochar machine flare. A matrix of tests was conducted at high and low flow rates for both the heat exchanger air flow rate (which varied the temperature and heat input to the dryer) and the residence time of feedstock in the belt dryer. Mean feedstock input moisture during dryer characterization was 45% and the mean moisture after exiting the dryer was 27%. The optimal test condition, providing the greatest water removal rate, was determined to have high air flow rate through the heat exchanger and short dryer residence time. This condition was used to demonstrate the integrated system for an 8-h production day. The integrated system dried incoming feedstock from 36% to 22% with a dryer throughput rate of 495 kg h -1 w.b. and an evaporation rate of 88.8 kg h -1 , providing the necessary dry feedstock for the 20-kW gasifier generator set and the biochar machine, which produced 75 kg h -1 of biochar. This system required the operational effort of 0.92 labor hours per production hour. Results from this demonstration indicate that the integrated system provides key benefits in a biochar production operation including greater control of feedstock drying and the ability to operate without an external (non-biomass) source of fuel for electricity generation. Keywords: Biochar, Biomass, Biomass drying, Forest residuals, Gasification, Pyrolysis.

Agriculture↗
DOE OSTI2014

Advanced Systems for Preprocessing and Characterizing Coal-Biomass Mixtures as Next-Generation Fuels and Feedstocks

The research activities presented in this report are intended to address the most critical technical challenges pertaining to coal-biomass briquette feedstocks. Several detailed investigations were conducted using a variety of coal and biomass feedstocks on the topics of (1) coal-biomass briquette production and characterization, (2) gasification of coal-biomass mixtures and briquettes, (3) combustion of coal-biomass mixtures and briquettes, and (4) conceptual engineering design and economic feasibility of briquette production. The briquette production studies indicate that strong and durable co-firing feedstocks can be produced by co-briquetting coal and biomass resources commonly available in the United States. It is demonstrated that binderless coal-biomass briquettes produced at optimized conditions exhibit very high strength and durability, which indicates that such briquettes would remain competent in the presence of forces encountered in handling, storage and transportation. The gasification studies conducted demonstrate that coal-biomass mixtures and briquettes are exceptional gasification feedstocks, particularly with regard to the synergistic effects realized during devolatilization of the blended materials. The mixture combustion studies indicate that coal-biomass mixtures are exceptional combustion feedstocks, while the briquette combustion study indicates that the use of blended briquettes reduces NO x , CO 2 , and CO emissions, and requires the least amount of changes in the operating conditions of an existing coal-fired power plant. Similar results were obtained for the physical durability of the pilot-scale briquettes compared to the bench-scale tests. Finally, the conceptual engineering and feasibility analysis study for a commercial-scale briquetting production facility provides preliminary flowsheet and cost simulations to evaluate the various feedstocks, equipment selection and operating parameters.

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2016

Renewable Enhanced Feedstocks for Advanced Biofuels and Bioproducts (REFABB)

The basic concept of the REFABB project was that by genetically engineering the biomass crop switchgrass to produce a natural polymer PHB, which is readily broken down by heating (thermolysis) into the chemical building block crotonic acid, sufficient additional economic value would be added for the grower and processor to make it an attractive business at small scale. Processes for using thermolysis to upgrade biomass to densified pellets (char) or bio-oil are well known and require low capital investment similar to a corn ethanol facility. Several smaller thermolysis plants would then supply the densified biomass, which is easier to handle and transport to a centralized biorefinery where it would be used as the feedstock. Crotonic acid is not by itself a large volume commodity chemical, however, the project demonstrated that it can be used as a feedstock to produce a number of large volume chemicals including butanol which itself is a biofuel target. In effect the project would try to address three key technology barriers, feedstock logistics, feedstock supply and cost effective biomass conversion. This project adds to our understanding of the potential for future biomass biorefineries in two main areas. The first addressed in Task A was the importance and potential of developing an advanced value added biomass feedstock crop. In this Task several novel genetic engineering technologies were demonstrated for the first time. One important outcome was the identification of three novel genes which when re-introduced into the switchgrass plants had a remarkable impact on increasing the biomass yield based on dramatically increasing photosynthesis. These genes also turned out to be critical to increasing the levels of PHB in switchgrass by enabling the plants to fix carbon fast enough to support both plant growth and higher levels of the polymer. Challenges in the critical objective of Task B, demonstrating conversion of the PHB in biomass to crotonic acid at over 90% yield, demonstrated the need to consider up-front the limitations of trying to adopt existing equipment to a task for which subsequent basic research studies indicated it was not suitable. New information was developed in the most complex of the chemical conversions studied, advanced catalysis to make acrylic acid, a chemical used widely to make paints, and this was published in a scientific journal. In regard to the technical effectiveness, the crop science aspects were for the most part remarkably effective in addressing the underlying objectives indicating the soundness of the technical approach. With time, it should be possible to fully develop the advanced biomass biorefinery feedstock. Challenges within the thermolysis step to recover crotonic acid meant that by the end of the project we were not able to demonstrate an economic case based on data from scaled up equipment. Solving this will take further research and development work. As a general statement, the broadest public good is in demonstrating the value of funding a very unique approach to the complex problem of enabling large-scale biomass biorefineries which resulted in significant progress towards the ultimate goal and a clearer understanding of the technical hurdles remaining. Perhaps not surprisingly, some of the broader benefits to the public come from the use of the REFABB project innovations in areas unrelated to the initial objective. It is worth highlighting the breakthrough developments in identifying three single global regulator genes which can be engineered into plants to dramatically increase photosynthesis and carbon capturing ability. These genes have tremendous potential for use in major food crops, in particular corn to enhance grain yield and based on recent findings, increase the root density, a critical key to increasing carbon sequestration in agriculture and improving the sustainability of global food and biofuel production.

09 BIOMASS FUELS↗
DOE OSTI2021

Feedstock Carbon Intensity Calculator (FD-CIC) Users’ Manual and Technical Documentation

A transparent and easy-to-use tool for feedstock-specific, farm-level CI calculation of feedstocks is helpful. With the ARPA-E support, we have developed a tool–the Feedstock Carbon Intensity Calculator (FD-CIC). The first version of FD-CIC was released with the GREET® model in 2020 (Wang et al., 2020) so that corn feedstock producers could use this publicly available tool (https://greet.es.anl.gov/tool_fd_cic) to quantify corn grain CIs with farm-level input data and management practices. In the 2021 version, we expand the tool’s capabilities by including additional feedstocks such as soybeans, sorghum, and rice. Similar to corn, it calculates the farm-level CI for these feedstocks by allowing user-defined farm-level farming inputs and incorporating the GHG emission intensities of these inputs from GREET (in particular, GREET1, the fuel cycle model of GREET).

09 BIOMASS FUELS↗