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Bioresource and Agricultural Engineering Commons

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Full-Text Articles in Bioresource and Agricultural Engineering

Rational Design Of Advanced Functional Materials For Electrochemical Devices, Shun Lu Jan 2021

Rational Design Of Advanced Functional Materials For Electrochemical Devices, Shun Lu

Electronic Theses and Dissertations

In recent years, there has been a fast-growing trend in developing urea (CO(NH2)2) as a substitute H2 carrier in energy conversion due to its high energy density, nontoxicity, stability, and nonflammability. Urea, a byproduct in the metabolism of proteins and a frequent contaminant in wastewater, is an abundant compound that has demonstrated favorable characteristics as a hydrogen-rich fuel source with 6.7 wt % gravimetric hydrogen content. Also, there is 2-2.5 wt % urea from mammal urine; therefore, 0.5 million ton of additional fuels will be produced per year just from human urine (240 million ton each year). Electrochemical oxidation has …


Using Computational Fluid Dynamics To Accurately Model Agricultural Spray Nozzles, Zachary Chapman Jan 2020

Using Computational Fluid Dynamics To Accurately Model Agricultural Spray Nozzles, Zachary Chapman

Electronic Theses and Dissertations

Computational fluid dynamics (CFD) is a tool used by engineers in many industries to study fluid flow. A relatively new industry to adopt the use of CFD is the agricultural industry. The present work seeks to understand whether CFD can be used to accurately model spray nozzles. A spray nozzle commonly used in agricultural spraying was simulated. First, the impact of factors such as mesh size, mesh type, and physics models have on the solution were investigated. Next, a method to pulse the spray was determined. This was required to compare simulation results with experimental data. A user-defined function was …


A Quantitative Environmental Assessment Of Incorporating Torrefaction Into Farming Enterprises In Eastern South Dakota, Dinesh Fuyal Jan 2018

A Quantitative Environmental Assessment Of Incorporating Torrefaction Into Farming Enterprises In Eastern South Dakota, Dinesh Fuyal

Electronic Theses and Dissertations

The use of renewable energy sources has been increasing in the recent years due to population growth and environmental concerns. Biomass is a promising energy source that can be used to produce biofuels or torrefied pellets. Torrefied biomass may be used in power plants, industrial and residential heating, feedstocks for gasification, air and water filtrating, and soil amendment. The interest of torrefied pellets as energy sources for various applications has been increased in the recent years due to the concerns about energy security and environmental issues. This study focuses on the economic and environmental assessment of agricultural feedstocks like corn …


Assessment Of Varying Model Representations In Cfd Simulations, Caitlin R. Gerdes Jan 2017

Assessment Of Varying Model Representations In Cfd Simulations, Caitlin R. Gerdes

Electronic Theses and Dissertations

This thesis investigates the effects of varying model refinement and representation of computational fluid dynamics (CFD) simulations in two case studies. Product and process realization in engineering design requires substantial resources (time and money) in order to test novel designs for effectiveness. In recent decades, engineering has been relying more heavily on simulation-based analysis in the design process with computer models to help reduce the demands for real-life testing. The first case study analyzed in this thesis is a photobioreactor, which is used to grow microalgae for biofuel and require a balance of nutrients, light, and mixing for growth. The …


Development Of Heterogeneous Catalysts For Upgrading Biomass Pyrolysis Bio-Oils Into Advanced Biofuels, Shouyun Cheng Jan 2017

Development Of Heterogeneous Catalysts For Upgrading Biomass Pyrolysis Bio-Oils Into Advanced Biofuels, Shouyun Cheng

Electronic Theses and Dissertations

The massive consumption of fossil fuels and associated environmental issues result in an increased interest in alternative resources such as biofuels. The renewable biofuels can be upgraded from bio-oils that are derived from biomass pyrolysis. Catalytic cracking and hydrodeoxygenation (HDO) are two most promising bio-oil upgrading techniques for biofuel production. Heterogeneous catalysts are essential for upgrading bio-oil into hydrocarbon biofuel. Although some progresses have been made, the cost and effectiveness of catalysts still remain challenges. The main objective of this study was to develop efficient heterogeneous catalysts for upgrading bio-oils into advanced hydrocarbon biofuel with low costs. In catalytic cracking, …


Assessment Of Corn Stover Torrefaction On-Farm Biochar Production, Christina M. Gerometta Jan 2014

Assessment Of Corn Stover Torrefaction On-Farm Biochar Production, Christina M. Gerometta

Electronic Theses and Dissertations

Torrefaction is a thermochemical pretreatment process that is typically achieved by slowly heating biomass (<50°C/min) within the temperature range of 200 – 300°C under an inert atmosphere. This process yields a storable solid product with enhanced fuel characteristics that are influenced by the ligno-cellulosic composition of the original feedstock and the imposed torrefaction conditions (time and temperature). This study is an assessment of corn stover properties that are relevant for designing an on-farm torrefaction system. The first portion of this study compared the thermal decomposition behaviors of corn stover fractions (leaf, stalk, cob) to the respective ligno-cellulosic composition using thermo-gravimetric analysis. It was found that the thermal decomposition pattern correlates to the structure and ratio of ligno-cellulosic polymers and provides design guidelines for an on-farm torrefaction system capable of handling large quantities of mixed fraction stover. The second part of this study investigated the effects of torrefaction time and temperature on the mass and energy yield of mixed fraction corn stover using a 46.3 L batch style reactor. It was found that longer reaction times and higher temperatures were required to obtain mass and energy yields similar to those found using lab-scale reactors and finely milled samples. Non-uniform torrefaction occurred between fractions due to chemical composition of each fraction and proximity to the heating elements.