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Optimal Draw Area And Feedstock Delivery Schedule Of Biorefineries In The Southeast U.S. Based On Least Cost And Producers’ Willingness To Plant A Dedicated Energy Crop, Wen Tu

Doctoral Dissertations

To overcome the limitations of starch-based and sugar-based ethanol, scientists propose to expand the use of cellulosic ethanol. Cellulosic ethanol is a biofuel produced from wood, grasses, or the non-edible parts of plants. As the U.S. has a large cellulosic biomass production base (Perlack et al., 2006), production of ethanol from cellulosic feedstock and use of ethanol as a substitute for gasoline could help promote rural development, reduce green house gases emissions, and increase energy independence. This study focuses on the cost of producing cellulosic ethanol along with the amount of carbon sequestered and emitted using switchgrass as a feedstock. …

Impact Of Switchgrass Bioenergy Feedstock Production On Soil Carbon Dioxide Flux And Below Ground Soil Organic Carbon Storage In East Tennessee, Leah Denise Soro

Masters Theses

Bioenergy production from switchgrass has shown promise in restoring degraded soils and helping to mitigate greenhouse gas (GHG) emissions. CO₂ loss and C-sequestration in soils are important topics for research to better understand the environmental impacts of bioenergy crops. The need for more thorough research of the carbon cycle in soils used for bioenergy production precipitated the primary interest of this study. The specific objectives of this study were 1) to measure SOC under switchgrass production in order to predict storage of carbon in soils based on previous cropping history, land management, soil physical characteristics, and time; and to …

Evaluation Of Capital Investment And Cash Flows For Alternative Switchgrass Feedstock Supply Chain Configurations, Jie Chen

Masters Theses

Biofuels have been widely recognized as a potential renewable energy source, and the United States’ government has been interested in producing ethanol from lignocellulosic biomass such as switchgrass. To evaluate whether lignocellulosic biomass based biofuels production is economically feasible, this paper estimated the capital investment outlays, operation costs, and net present value for investment in alternative switchgrass feedstock supply chain configurations in East Tennessee a 25 million gallon per year ethanol biorefinery. Two scenarios are analyzed in the study. The conventional hay harvest scenario includes the production, harvest, storage and transportation of biomass feedstocks from the fields to the biorefinery. …

Establishment And Persistence Of Legumes In Switchgrass Biomass And Forage/Biomass Production Systems, Kara Spivey Warwick

Masters Theses

Switchgrass, Panicum virgatum, is being developed as an economically and ecologically sustainable biomass crop. Nitrogen is considered one of the most limiting inputs of switchgrass. Alternatives to synthetic nitrogen fertilization may be nitrogen-fixing legumes interseeded into switchgrass. The objectives of this research were: (1) develop efficient legume management strategies for switchgrass production systems, (2) evaluate and identify cool and warm-season legumes that can be grown compatibly with switchgrass, (3) determine whether switchgrass yields are increased by legume N-fixation, and (4) determine N-fixation of common (Vicia sativa) and hairy vetch (Vicia villosa).

This study examined the …

Evaluation Of Pre-Processing And Storage Options In Biomass Supply Logistics: A Case Study In East Tennessee, Yuan Gao

Masters Theses

Biofuels have been widely recognized as a potential renewable energy source that can lessen the United States’ dependence on imported petroleum and enhance the domestic economy. Particularly, biofuels derived from lignocellulosic biomass (LCB) have been the focus in the development of a sustainable biofuels industry. However, technical barriers in the LCB feedstock supply chain have been one of the major challenges impeding the economic viability of this industry. To expedite the commercialization process of LCB-based biofuels production, this paper employed a spatial mixed-integer mathematical model to explore the optimal biomass logistic system for a switchgrass-based biofuels biorefinery in East Tennessee. …

Analysis Of Factors Affecting Farmers’ Willingness To Adopt Switchgrass Production In The Southern United States And An Excel Spreadsheet-Based Decision Tool For Potiential Switchgrass Producers, Donald Joshua Qualls

Masters Theses

The increased need for and scarcity of hydrocarbon energy pushes the search and extraction of reserves toward more technically difficult deposits and less efficient forms of hydrocarbon energy. The increased use of hydrocarbons also predicates the increased emission of detrimental chemicals in our surrounding environment. For these reasons, there is a need to find feasible sources of renewable energy that could prove to be more environmentally friendly.

One possible source that meets these criteria is biomass, which in the United States is the largest source of renewable energy as it accounts for over 3 percent of the energy consumed domestically …