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Full-Text Articles in Engineering

Gasification Of Liquid Sprays In An Entrained Flow Gasifier, Nicholas Ryan Creager Jan 2016

Gasification Of Liquid Sprays In An Entrained Flow Gasifier, Nicholas Ryan Creager

Graduate Theses and Dissertations

In an advancing technological world, gasification is a relatively mature technology that can be refreshed to help achieve sustainable energy production. This thesis discusses the development of a pressurized gasification system that converts bio-oil from fast pyrolysis of red oak into producer gas. Focus will be given to the challenges of operating a pressurized system at high temperature while injecting a non-uniform liquid. Demonstration experiments using methanol resulted in development of experimental methods to show critical nozzle designs and their affects on gasification of liquid jets.

Start up of the bio-oil gasification system was performed using methanol as a model ...


Techno-Economic, Uncertainty, And Optimization Analysis Of Commodity Product Production From Biomass Fast Pyrolysis And Bio-Oil Upgrading, Wenhao Hu Jan 2015

Techno-Economic, Uncertainty, And Optimization Analysis Of Commodity Product Production From Biomass Fast Pyrolysis And Bio-Oil Upgrading, Wenhao Hu

Graduate Theses and Dissertations

Advanced biofuel is a promising replacement to fossil fuels for the purpose of protecting the environment and securing national energy supply, but the high cost of producing advanced biofuels makes it not as competitive as petroleum-based fuels. Recent technology developments in biomass fast pyrolysis and bio-oil upgrading introduced several innovative pathways to convert bio-oil into other commodity products, such as bio-asphalt, bio-cement, dextrose and benzene, toluene, xylene (BTX). Before commercializing these products, a comprehensive techno-economic analysis should be employed to examine the economic feasibility of producing them. This thesis compared the economic performance of biofuels, biochemicals, and hydrocarbon chemicals portfolios ...


The Effect Of Process Variables On Pyrolysis In A Freefall Reactor, Preston Gable Jan 2014

The Effect Of Process Variables On Pyrolysis In A Freefall Reactor, Preston Gable

Graduate Theses and Dissertations

The focus of this work is to test variables of fast pyrolysis conditions in a free fall reactor in order to better understand their impact on pyrolysis products, specifically optimization of bio-oil yields. In the first study, a design of experiments was performed and products were analyzed to evaluate the effects of temperature, sweep gas flow rates, and particle heating time, on bio-oil yields. This study proved particle heating time to be a very important variable effecting bio-oil yields, and that a heating time of greater than the traditionally assumed two seconds must be achieved in order to optimize yields ...


Analysis Of Sugars And Phenolic Compounds In Bio-Oil, Marjorie Ruth Rover Jan 2013

Analysis Of Sugars And Phenolic Compounds In Bio-Oil, Marjorie Ruth Rover

Graduate Theses and Dissertations

The overall goal of this research is to develop methods for analyzing and recovering sugars and phenolic compounds from bio-oil. Specific objectives include (1) adapting analytical methods developed for sugar analysis in the food industry to measure total water-soluble sugars in the aqueous phase of bio-oil; (2) adapting analytical methods developed for total phenolic analysis of wine to measure total phenolic content of bio-oil; (3) separate the heavy fraction of bio-oil into a concentrated sugar solution and a phenolic oligomer-rich raffinate; and (4) determine the effect of pyrolysis temperature on the yield of sugars and phenolic compounds in bio-oil.

Recent ...


Pyrolytic Sugars From Cellulosic Biomass, Najeeb M. Kuzhiyil Jan 2013

Pyrolytic Sugars From Cellulosic Biomass, Najeeb M. Kuzhiyil

Graduate Theses and Dissertations

Sugars are the feedstocks for many promising advanced cellulosic biofuels. Traditional sugars derived from starch and sugar crops are limited in their availability. In principle, more plentiful supply of sugars can be obtained from depolymerization of cellulose, the most abundant form of biomass in the world. Breaking the glycosidic bonds between the pyranose rings in the cellulose chain to liberate glucose has usually been pursued by enzymatic hydrolysis although a purely thermal depolymerization route to sugars is also possible. Fast pyrolysis of pure cellulose yields primarily levoglucosan, an anhydrosugar that can be hydrolyzed to glucose. However, naturally occurring alkali and ...


Development Of A Co-Firing Fuel From Biomass-Derived Binder And Crushed Coal, Andrew Friend Jan 2013

Development Of A Co-Firing Fuel From Biomass-Derived Binder And Crushed Coal, Andrew Friend

Graduate Theses and Dissertations

The focus of this work was the development of a co-firing boiler fuel for use in the coal power plant industry. This fuel, known as co-fire pellets, is a densified product comprised of crushed coal and a renewable binder derived from the liquid product of the fast pyrolysis of lignocellulosic biomass. The co-fire pellets can help meet certain state and federal regulations related to electricity production. A central composite design of experiments was used to evaluate properties of the co-fire pellets based on four factors relating to the makeup of the pellets. These factors are coal particle size, coal moisture ...


Carbon-Carbon Bond Forming Reactions For Bio-Oil Upgrading: Heterogeneous Catalyst And Model Compound Studies, Ryan William Snell Jan 2012

Carbon-Carbon Bond Forming Reactions For Bio-Oil Upgrading: Heterogeneous Catalyst And Model Compound Studies, Ryan William Snell

Graduate Theses and Dissertations

Development of a renewable liquid transportation fuel is likely to be one of the most important challenges faced by scientists during the 21st century. As biomass provides a renewable source of carbon it is ideally situated to supply this alternative to the traditional petroleum derived feedstocks. While there have been a number of different techniques used to convert biomass to liquid fuels, fast pyrolysis is particularly promising as it can quite efficiently break down biomass directly into a liquid. This resulting liquid, called bio-oil, is a very complex mixture containing a large number of oxygen functionalized compounds. Unfortunately, this oil ...


Steam Reforming Of Water-Soluble Fast Pyrolysis Bio-Oil: Studies On Bio-Oil Composition Effect, Carbon Deposition, And Catalyst Modifications, Pedro J. Ortiz-Toral Jan 2011

Steam Reforming Of Water-Soluble Fast Pyrolysis Bio-Oil: Studies On Bio-Oil Composition Effect, Carbon Deposition, And Catalyst Modifications, Pedro J. Ortiz-Toral

Graduate Theses and Dissertations

Bio-oils from fast pyrolysis of lignocellulosic biomass can be phase separated into a heavy water insoluble portion and a light water-soluble portion. The water-rich portion contains mainly carboxylic acids, carbohydrates, aldehydes, ketones and alcohols. This highly oxygenated water-rich portion was evaluated for production of the renewable hydrogen required for the upgrading reactions. There are certain challenges introduced due to the complexity of these mixtures. Catalyst deactivation by coking and the formation of carbon deposits are major limitations although the specific causes were previously unidentified. A bio-oil fractionating system can separate heavier components from the light-end components. This light-end fraction has ...


Asphalt Modification By Utilizing Bio-Oil Esp And Tall Oil Additive, Sheng Tang Jan 2010

Asphalt Modification By Utilizing Bio-Oil Esp And Tall Oil Additive, Sheng Tang

Graduate Theses and Dissertations

Bio-oil is a dark-brown, mobile liquid derived from the thermo-chemical processing of biomass. Bio-oils generally contain water and lignin. Lignin is a highly-available, well-studied carbohydrate derivative known for its antioxidant properties. For asphalt pavements, oxidation can cause deterioration via long-term aging and eventually result in cracking. Therefore, bio-oil could potentially serve as an antioxidant additive in asphalt mixtures. The main objective of this research is to evaluate the effects of lignin-containing bio-oil for utilization in asphalt binders, and attempt to optimize the bio-oil modification formula by adding other additives. Using bio-oil as an antioxidant in asphalt production could prove to ...


Understanding The Product Distribution From Biomass Fast Pyrolysis, Pushkaraj Ramchandra Patwardhan Jan 2010

Understanding The Product Distribution From Biomass Fast Pyrolysis, Pushkaraj Ramchandra Patwardhan

Graduate Theses and Dissertations

Fast pyrolysis of biomass is an attractive route to transform solid biomass into a liquid bio-oil, which has been envisioned as a renewable substitute for crude oil. However, lack of fundamental understanding of the pyrolysis process poses a significant challenge in developing cost-effective pyrolysis based technologies for producing transportation fuels. The fundamental knowledge of pyrolysis pathways, product distribution and underlying mechanisms will have a direct and significant impact on the reactor design, strategic operation and kinetic modeling of the pyrolysis process. However, this knowledge has remained obscure due to the complexity of the pyrolysis process and lack of well established ...


Development Of A Lab-Scale Auger Reactor For Biomass Fast Pyrolysis And Process Optimization Using Response Surface Methodology, Jared Nathaniel Brown Jan 2009

Development Of A Lab-Scale Auger Reactor For Biomass Fast Pyrolysis And Process Optimization Using Response Surface Methodology, Jared Nathaniel Brown

Graduate Theses and Dissertations

A lab-scale biomass fast pyrolysis system was designed and constructed based on an auger reactor concept. The design features two intermeshing augers that mix biomass with a heated bulk solid material that serves as a heat transfer medium. A literature review, engineering design process, and shake-down testing procedure was included as part of the system development.

A response surface methodology was carried out by performing 30 experiments based on a four factor, five level central composite design to evaluate and optimize the system. The factors investigated were: (1) heat carrier inlet temperature, (2) heat carrier mass feed rate, (3) rotational ...


Design, Optimization And Evaluation Of A Free-Fall Biomass Fast Pyrolysis Reactor And Its Products, Cody James Ellens Jan 2009

Design, Optimization And Evaluation Of A Free-Fall Biomass Fast Pyrolysis Reactor And Its Products, Cody James Ellens

Graduate Theses and Dissertations

The focus of this work is a radiatively heated, free-fall, fast pyrolysis reactor. The reactor was designed and constructed for the production of bio-oil from the fast pyrolysis of biomass. A central composite design of experiments was performed to evaluate the novel reactor by varying four operating conditions: reactor temperature, biomass particle size, carrier gas flow rate and biomass feed rate. Maximum bio-oil yields of 72 wt % were achieved at a heater set point temperature of 600 yC, using particle sizes of 300 micron, carrier gas flow rates of 4 sL/min and Red oak biomass feed rates of 1 ...


Steam Reforming Of Bio-Oil: Effect Of Bio-Oil Composition And Stability, Pedro J, Ortiz-Toral Jan 2008

Steam Reforming Of Bio-Oil: Effect Of Bio-Oil Composition And Stability, Pedro J, Ortiz-Toral

Graduate Theses and Dissertations

Hydrogen can be obtained from biomass pyrolysis liquids by catalytic steam reforming. Catalyst deactivation by coking and the formation of carbon deposits are the major known limitations although the specific causes are unidentified. It is proposed that these limitations could be reduced by selectively reforming specific fractions of the bio-oil. The hydrophobic fraction mainly composed of heavy oligomers can be separated by water extraction as a high-value product. In the current work, the particular interest is on efficient hydrogen production from the residual aqueous fractions. There are certain challenges introduced due to the complexity of these mixtures. An improved understanding ...