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Steve Kelley

Reuben B. Robertson Professor

Biltmore Hall (Robertson Wing) NA

Bio

Dr. Steve Kelley is a Professor at North Carolina State University and interim Department Head. His research interests include the sustainable production of energy and materials from biomass, and the application of novel analytical tools to biomass. He teaches classes in Wood Chemistry (FB 301) and Wood Adhesives and Composites (FB 444). In addition to his research and teaching, he has also helped develop international partnerships for the Department.

Prior to joining NCSU, he spent 13 years at the DOE’s National Renewable Energy Laboratory (NREL) working on biomass conversion technologies. At NREL his responsibilities included technical leadership and innovation in the areas of biomass characterization, production of value-added biobased products and thermal conversion processes, and project management. He left NREL as a Principal Scientist. Prior to joining NREL, he worked in industry (Eastman Chemical Co. and Bend Research, Inc.) for 7 years developing new cellulose-based materials and membrane processes.

Research

Bioethanol from Wood Hemicelluloses (Jameel, Phillips, Chang, Kelley) This collection of projects involve the production of ethanol from hemicellulose sugars extracted woody biomass. The work includes wood extraction; characterization of the extracts and extracted wood; clean-up of the extracted sugars; ethanol production; technoeconomic modeling of the process.

Woody Biomass Quality Study (Hazel, Kelley)This collection of projects is focused on measuring the chemical composition and physical properties of many sources of woody biomass and developing an understanding on the biomass resource impacts the cost of converting the biomass into fuels and products.

Thermochemical Conversion of Woody Biomass (Jameel, Peretti, Dayton, Kelley)This work is focused on developing thermochemical process for converting biomass into fuels and products. This work includes a recent $3.2 million DOE funded demonstration project that includes work at NCSU, Research Triangle International (Dayton), and the University of Utah (Winger), that will demonstrate gasification of wood biomass, novel gas cleanup catalysts, and gas-to-liquids production.

Cellulose Based Materials (Rojas, Heitmann, Kelley) This work includes the preparation and characterization of cellulose polymers, copolymers and blends. In particular this work is focused on the molecular level mixing behavior of cellulose copolymers and blends of cellulose copolymers with other organic and inorganic polymers.

Area(s) of Expertise

Sustainable production of energy and materials from biomass, and the application of novel analytical tools to biomass

Publications

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Grants

Date: 01/01/20 - 12/31/24
Amount: $127,993.00
Funding Agencies: NC Department of Agriculture & Consumer Services

Loblolly pine is the most abundant commercially grown tree species in North Carolina with over 100,000 acres of pine plantations established each year in the state. In addition to the conventional forest products industry, loblolly pine serves as a promising source for renewable energy in the form of woody biomass. Large genetic differences exist for growth, disease resistance, and stem form. By planting genetically superior trees with desirable traits, it may be possible to substantially increase the amount and quality of biomass produced at a given site. The goal of this project is to evaluate different planting stock (families) in combination with different thinning regimes in order to inform forest landowners how best to maximize their returns when supplying both the bioenergy and sawtimber markets. This project was initiated in 2012, with the planting of a high spacing density (1037 trees/acre) long-term field trial in the NC Piedmont. The trial includes 10 of the best Coastal and 10 of the best Piedmont families with varying degrees of adaptation, growth, and wood characteristics. Different thinning regimes will be explored using eight year measurements, and the predicted financial returns from the thinnings as well as projected sawtimber production will be evaluated.

Date: 09/15/20 - 9/14/24
Amount: $82,622.00
Funding Agencies: US Dept. of Agriculture (USDA)

The hygiene tissue industry (bath tissue and kitchen towel) is an annual 39 million tons - USD 100 billion - global market with a forecast to grow ~ 3% per year for the next decade [38], [39]. Most hygiene tissue paper grades require the use of both long and short virgin fibers, which provide strength and softness respectively [8]. As an effect of global megatrends, the demand for non-woody biomass for tissue manufacturing will continue to increase [40], and agricultural biomass, which is perceived to be a sustainable option, can be an important source of short fibers for the tissue industry [41]. Therefore, the need to research and create knowledge on the handling and conversion of biomass sorghum and switchgrass to produce sustainable and high-end fiber furnish for the hygiene tissue industry. The proposed feedstock can be established to supply fiber at industrial scale.

Date: 10/01/20 - 12/31/23
Amount: $2,649,938.00
Funding Agencies: US Dept. of Energy (DOE) - Energy Efficiency & Renewable Energy (EERE)

We will improve and validate the critical unit operations needed for producing high-value carbon materials (graphite and hard carbon) used for lithium ion and sodium ion batteries from a faction of the biocrude produced by biomass fast pyrolysis. This work will bring together two innovations, 1) production of high-value carbon materials from the biocrude heavy residues fraction, which are often difficult to convert into biofuels, and 2) process innovations that should lower the costs for producing these high-value carbons. In order to produce high-value carbons, the biocrude residues are sequentially heated to remove volatiles and oxygen, polymerize the biomass carbons into graphene sheets, and in a second step form either highly crystalline graphite or disordered hard carbon. The graphite can be used in as drop-in anode material in existing commercial lithium ion battery (LIB) applications such as portable electronics and electric vehicles (EVs), while the hard carbon can be used in emerging and advancing battery applications, such as sodium ion battery (SIB) for grid electrochemical energy storage and LIB for hybrid batteries in EV with high capacity and good rate capability. The team has demonstrated that both graphite and hard carbon can be produced from pyrolysis biocrudes at laboratory scale and has measured their electrochemical performance in batteries. This work will optimize the range of operating parameters, with a focus on the complex interactions between the chemical changes and the heat and mass transfer characteristics of the reactor and increase the production scale to obtain mass and energy balances that are relevant for modeling commercial potential. The performance of the carbon materials will be evaluated to define their values in commercial systems. Both techno-economics (TEA) and life cycle analysis (LCA) will be performed to understand the economic and environmental impact of the proposed technology. Preliminary revenue analysis suggests diverting 15-25% of the biocrude, essentially all of the heavy and less valuable fraction, into high-value carbons like graphite or hard carbon can significantly improve the profits of a biorefinery and lower the cost of making biofuels. The goal of this project is to optimize and scale-up the process for producing graphite and hard carbon that meet the requirement for LIB and SIB, respectively. Performance specification will be measured, including electrochemical performance under varying conditions (e.g., operating voltage range, current density, and c-rate) using coin-type and pouch cells. We will use a suite of advanced analytical tools to develop a more detailed understanding of 1) how the chemical composition of biocrude and the carbonization process impact the macromolecular ordering of the final products and 2) how the changes in carbon structure influence on the ion storage behavior (e.g., (de)insertion and adsorption/desorption) and subsequent electrochemical performance. In addition to the performance of the carbon materials, we will determine yields in order to close the mass and energy balances of the process. This data will be used to conduct rigorous TEA and LCA models to demonstrate the target FOA metrics such as $3.00/GGE fuel selling price and 60% reduction in emission. Successful completion of the scale up of bio-based graphite and hard carbon production will enable commercialization of these processes and will have an important impact on several sustainable technologies, 1) the low cost biocrude, the bio-based graphite will reduce the cost for LIB that can be used in EVs, 2) the low cost of hard carbon production will enable SIB for energy grid storage and LIB for advanced batteries for EVs, supporting continued growth of PV and wind electricity generation, and 3) commercial production of graphite and hard carbon as biorefinery co-products will improve the overall economics of producing biofuels.

Date: 11/15/18 - 11/14/23
Amount: $238,500.00
Funding Agencies: US Dept. of Agriculture - National Institute of Food and Agriculture (USDA NIFA)

Led by the Department of Forest Biomaterials in collaboration with the Departments of Forestry, Business Management and Science Education at NC State University; this proposal will develop an educational program for a new generation of technology-to-commercialization researchers who will graduate with the expertise to perform risk analysis and develop risk management strategies across the value chain of biomass supply, biobased materials, and biofuels manufacturing to meet current and future national needs that will ultimately advance the nascent bioeconomy of the United States. Previous studies indicate that a limited number of companies in the forest product industry perform risk analysis for their decision-making process. We do believe that this small adoption rate is due to lack of awareness of the importance of risk analysis and risk management for effective/efficient R&D planning and investment and lack of expertise (people trained) to perform risk analysis across the whole supply chain. This proposal supports TESA in “Agricultural Management and Economics”, in the discipline of Environmental Sciences/Management. Three Ph.D. students will be trained to analyze and propose mitigation strategies for current and future risks inherent to the bioeconomy. To considerably amplify the effect of this proposal, prospective fellows and project directors will deliver educational workshops in risk analysis and management targeting the biobased community across the U.S., while the proposal is expected to be completed in three years, project director expects to keep the program as a permanent teaching/research program. This proposed program supports USDA-NIFA Goal “Catalyze exemplary and relevant research, education and extension programs”.

Date: 10/01/22 - 9/30/23
Amount: $0.00
Funding Agencies: US Dept. of Energy (DOE) - Energy Efficiency & Renewable Energy (EERE)

This project will merge NREL’s highly robust biomass fractionation and fermentation technology and NCSU’s highly robust graphitization technology to convert two waste streams that are increasingly problematic in the southeastern US and Caribbean states (hurricane-damaged wood waste and Sargassum seaweed) into Sustainable Aviation Fuel (SAF) and graphite for lithium ion batteries (LIB), as shown in Figure 1. NREL has developed fractionation technology for biomass and algae that solubilizes carbohydrates and proteins of varying composition into fermentable hydrolysates. Hydrolysates from woody biomass contain abundant carbohydrates but are typically nutrient-poor for fermentation and require added nutrients, such as nitrogen. Algae (both micro- and macroalgae) hydrolysates are also rich in carbohydrates but are often over-rich in nutrients. Thus, combining these two waste stream hydrolysates in an appropriate ratio will maximize fermentation productivity of SAF precursor (ethanol) while keeping wood waste and Sargassum out of landfills. NCSU and NREL have also demonstrated synthesis of battery-grade graphite from a variety of sustainable feedstocks, including pyrolysis oil, lignin, and cellulose using metallic iron catalysts. This technology is also expected to work well with the insoluble residues from the waste streams described above. The proposed fermentation pathway presents a viable pathway to helping reach BETO’s goal of producing 3 billion gal/year of SAF and the graphite production is compatible with the rapidly growing market for LIB (20% per annum) for portable electronics and electric vehicles.

Date: 10/01/18 - 9/30/23
Amount: $1,250,807.00
Funding Agencies: US Dept. of Energy (DOE) - Energy Efficiency & Renewable Energy (EERE)

The objective of this project is to demonstrate catalytic processes for upgrading carbohydrates to hydrocarbon biofuels using two low-cost wet organic waste streams: Papermaking sludge and Post-sorted municipal solid waste. The work is based on the previous success of hydrocarbon production from corn stover in a bench scale via dilute-acid and enzymatic deconstruction followed by dehydration to furans, condensation, and hydrodeoxygenation to hydrocarbons. The project team will develop (1) a sugar production process and a removal strategy of non-carbohydrates that could poison catalysts during the conversion process, (2) isomerization and dehydration processes necessary to convert both glucose and xylose to furans in a single reactor, (3) an upgrading process of furans via aldol condensation with ketone and hydrodeoxygenation to diesel range hydrocarbons, and (4) a detailed techno-economic analysis to integrate and optimize the overall process. The developed process in this project will be demonstrated in a relevant pilot-scale and life cycle assessment will be evaluated.

Date: 07/01/21 - 6/30/23
Amount: $719,873.00
Funding Agencies: NCSU Consortium Sustainable and Alternative Fibers Initiative (SAFI)

The purpose of the Consortium on Sustainable and Alternative Fibers Initiative (SAFI) is to develop fundamental and applied research on the use of alternative and sustainable fibers for the manufacturing of market pulp, hygiene products and nonwovens. The idea for SAFI has grown out of societal needs for alternative yet sustainable materials. SAFI will study the potential of alternative fibers based on technical (performance), sustainable and economic principles.

Date: 06/15/17 - 6/14/23
Amount: $2,750,000.00
Funding Agencies: US Dept. of Agriculture - National Institute of Food and Agriculture (USDA NIFA)

The project will prepare a diverse group of college students and high school teachers with the knowledge and interdisciplinary tools necessary to advance the future of America’s bioenergy, bioproducts, and the bioeconomy. Distance courses will be developed and taught by faculty in the Departments of Forest Biomaterials & Environmental Resources, with guidance from the College of Education, undergraduate students are recruited from historically underserved institutions (HBCU, women’s college, community college), as are teachers from rural, high poverty NC high schools. Undergraduates will complete three of the five online courses in bioenergy & bioproducts, and complete an industry internship, and earn a certificate. Bioproducts and bioenergy industrial and research organization partners provide hands-on internship projects in the industry or in a research setting. Rural high school science teachers will complete three of the five online courses, earn a certificate, participate in professional development workshops, carry out lessons with their students during the school year, and conduct a career fair in bioproducts and bioenergy.

Date: 01/21/21 - 2/28/23
Amount: $68,446.00
Funding Agencies: US Dept. of Agriculture (USDA)

The hygiene tissue industry (bath tissue and kitchen towel) is an annual 39 million tons - USD 100 billion - global market with a forecast to grow ~ 3% per year for the next decade [38], [39]. Most hygiene tissue paper grades require the use of both long and short virgin fibers, which provide strength and softness respectively [8]. As an effect of global megatrends, the demand for non-woody biomass for tissue manufacturing will continue to increase [40], and agricultural biomass, which is perceived to be a sustainable option, can be an important source of short fibers for the tissue industry [41]. Therefore, the need to research and create knowledge on the handling and conversion of biomass sorghum and switchgrass to produce sustainable and high-end fiber furnish for the hygiene tissue industry. The proposed feedstock can be established to supply fiber at industrial scale.

Date: 01/01/22 - 12/31/22
Amount: $82,038.00
Funding Agencies: Siontech co., Ltd.

Development of graphite foil for water membrane application. Biomass will be graphitized, exploited, and then pressed into a foil structure. Key properties will be tensile strength, electric resistance, and thickness.


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