Bioresource and Agricultural Engineering Commons^™

Hydrothermal Liquefaction (Htl) Of Lignocellulosic Biomass For Biocrude Production: Reaction Kinetics And Corrosion-Resistance Performance Of Candidate Alloys For Reactors, Haoyu Wang

Electronic Thesis and Dissertation Repository

In recent years, the rapid increase in the demand for clean energy and green chemicals as well as concerns over the supply and environmental impacts associated with fossil. resources have stimulated intensive research on conversion of bioresources, such as lignocellulosic biomass and biowaste, into energy, fuels, chemicals, and materials.

Hydrothermal liquefaction (HTL) is a unique thermochemical conversion process, particularly applicable for the conversion of wet biomass and biowaste feedstocks. Most of the biomass HTL studies are conducted in batch reactor and focus on the effects of catalysts, reaction temperature and time on production efficiency and chemical properties of the products. …

Waste Hemp Fibers (Hfs) Derived Porous Carbons: Preparation, Characterization, And Potential Applications, Manju Gurung

Electronic Thesis and Dissertation Repository

The main objective of the present research was to develop environmentally friendly and cost-effective porous carbon materials of improved properties from waste hemp fibers. Two different types/categories of porous carbons were prepared from hemp fibers. In one type, porous carbon materials were developed by a simple one-step method of carbonization and activation. The other type of carbon materials developed in this study were nitrogen-containing activated carbons, which were developed by introduction of nitrogen-containing functional groups on the surface of hemp fibers followed by activation and carbonization. The pore structure/distribution and surface chemistry of the prepared carbons were investigated through the …

Improved Fermentation Design And Screening Devices For Biobutanol Production, Garret Christopher Munch

Electronic Thesis and Dissertation Repository

A worldwide increase in demand for renewable fuels has revived interest in fermentatively produced butanol. However, butanol fermentation suffers from low product yields and productivity. The work presented in this thesis addresses part of these research and development needs at three levels: innovative fermentation process design; genetic manipulation for strain enhancement; and the development of a new tool for anaerobic process characterization and optimization.

Product yield could be increased through traditional fermentation engineering. Co-fermentation of butyric acid with glycerol increased the butanol yield from 0.45 mol/mol (mols C in butanol / mol C in substrates) to 0.51 mol/mol. In building …

Highly Efficient Depolymerization Of Kraft Lignin (Kl) And Hydrolysis Lignin (Hl) Via Hydrolysis And Oxidation, Zaid Ahmad

Electronic Thesis and Dissertation Repository

Due to dwindling fossil resources, climate change and other environmental concerns as well as the toxicity of certain products derived from petroleum resources, there is a growing interest in exploring and utilizing the abundant biomass resources as alternative feedstocks for the production of bio-based chemicals and materials. Biomass is composed of three main macromolecules, namely: cellulose, hemicellulose, and lignin. Even though most of the initial work relating to the valorization of biomass was focused on the carbohydrate components (cellulose and hemicellulose), in the last ten years, lignin, an aromatic biopolymer, has been receiving increasingly more attention. In particular, various routes …

Anaerobic Digestion Of Aqueous Pyrolysis Condensate, Connie Wen

Electronic Thesis and Dissertation Repository

Lignocellulosic material can be subjected to pyrolysis to yield pyrolysis liquid, biochar, and gas. The pyrolysis liquid resulting from the condensation of vapours can be separated into a rich organic condensate and an acidic “aqueous pyrolysis condensate” (APC) which may be considered a waste. The target of this research is subjecting APC to anaerobic digestion to produce biogas that can be energy purposed, and to reduce the organic load of APC to acceptable levels for possible disposal. From this study, it was found that without any treatment, the inoculum requires 50 to 60 days of adaptation period to reduce the …

Autohydrolysis Pretreatment Of Mixed Lignocellulosic Biomass, Claudio Lira

Electronic Thesis and Dissertation Repository

Lignocellulosic biomass, such as agricultural and forestry residues, can be transformed into valuable fuels and chemicals. However, the high cost of feedstock handling and the complex nature of cellulosic biomass processing and conversion remain two major challenges in biorefineries. This thesis aims to tackle these challenges by assessing the transformation of multi-feedstock using autohydrolysis pretreatment.

Corn cobs and stover (residues from corn processing), poplar chips (forestry residue), bagasse and wheat straw (agricultural residues) are abundant and often under-utilized cellulosic residues. These feedstocks were used to investigate the effects of biomass characteristics on the composition of the autohydrolysis pretreatment products. Moreover, …

Biobutanol Production From Cellulosic And Sugar-Based Feedstock From The Corn Plant, Reyna Gomez-Flores

Electronic Thesis and Dissertation Repository

In this thesis, biobutanol production by biological fermentation was investigated from the corn plant, integrating two approaches. The first one was to utilize corn cobs, a cellulosic-based material. The second, using a new sugar-based material, sugarcorn juice. Utilizing suitable Clostridia strains for each substrate, these approaches converged into a biorefinery concept to produce renewable biofuels in Ontario, Canada. The corn cob pretreatment was carried out by a dilute acid method resulting in temperature as the variable with most significant effect towards glucose liberation. The enzymatic hydrolysis was performed utilizing a very low concentration of an enzymatic stock solution with approximately …

Abe Fermentation From Low Cost Substrates, Kai Gao

Electronic Thesis and Dissertation Repository

The high cost of substrate and product inhibition in the fermentation broth remains two major problems associated with bio-butanol production. This thesis aims to solve these problems by examining abundant lignocellulosic biomass as potential feedstocks and exploring novel substrates such as carbohydrates derived from microalgae for ABE fermentation. The commonly observed toxic effect after pretreatment of lignocelluslosic biomass was removed by resin adsorption, where the resin could also serve as an in-situ butanol recvoery devices.

Corn cobs (an agricultural waste), switchgrass (an energy crop) and phragmites (an invasive plant in North America) were investigated as substrates for ABE fermentation by …

Fractionation Of Cornstalk Into Cellulose And Lignin For The Production Of Sodium Carboxymethyl Cellulose, Tao Shui

Electronic Thesis and Dissertation Repository

This thesis project aimed to fractionate cornstalk into cellulose and lignin, and utilize the crude cornstalk-derived cellulose for the production of sodium carboxymethyl cellulose and the lignin for the sybthesis of bio-based phenol-formaldehyde resole resins as wood adhesives. In this thesis work, cornstalk was efficiently fractionated into crude cellulose and crude lignin in mixed solvents of acetic acid, formic acid and water at a solid/agent ratio of 1:5 (g/mL) at 80-100 °C for 120-240 min. The best conditions for organosolv fractionation of cornstalk among the test conditions were determined as follows: mixed solvent of acetic acid/formic acid/water (3:6:1, v/v/v), HCl …

Production Of Bio-Based Phenol Formaldehyde Foams, Bing Li

Electronic Thesis and Dissertation Repository

Considering the declining non-renewable fossil resources, there is increasing interest in the development of more environmentally conscious, sustainable and cost-effective substitutes for chemical production. Lignin, a main component in lignocellulosic biomass, has been considered to be a potential substitute for petroleum-based phenol due to its phenolic structure.

This PhD dissertation aimed at producing bio-based phenol formaldehyde (BPF) foams using bio-phenols, including but not limited to, kraft lignin (KL), organosolv lignin (OL), hydrolysis lignin (HL), and bio-crude oil from white birth bark. The challenge of the existing process of producing BPF foams is that a low phenol substitution ratio, generally less …

Development Of An Autonomous Robotic Mushroom Harvester, Nikita Alexeevich Kuchinskiy

Electronic Thesis and Dissertation Repository

The process of development of a new robot is one of the modern technological arts. This process involves multiple complex steps and recursive approach. In this project, a solution for automatic harvesting of mushrooms is developed. In order to design an effective solution, it is necessary to explore and take into consideration the limitations of grasping very soft and fragile objects (particularly mushrooms). We will elaborate several strategies of picking and analyze each strategy to formulate the design requirements, develop a solution, and finally, evaluate the efficiency of the proposed solution in actual farm conditions for real mushrooms. The mushroom …

Application Of 3d Printing Technology In Porous Anode Fabrication For Enhanced Power Output Of Microbial Fuel Cells, Bin Bian

Electronic Thesis and Dissertation Repository

Microbial fuel cells (MFCs) are widely researched for application in wastewater treatment. However, the current anodes used in MFCs often suffer from high fabrication cost and uncontrollable pore sizes. In this thesis, three-dimensional printing technique was utilized to fabricate anodes with different micro pore sizes for MFCs. Copper coating and carbonization were applied to the printed polymer anodes to increase the conductivity and specific surface area. Voltages of MFCs with various anodes were measured as well as other electrochemical tests such as linear sweep voltammetry and electrochemical impedance spectroscopy. 3D copper porous anode produced higher maximum voltages and power densities …

Novel Carbon-Supported Transition Metal Phosphide Catalysts For Hydrodeoxygenation Of Fast Pyrolysis Oil, Cheng Guo

Electronic Thesis and Dissertation Repository

Catalytic hydrodeoxygenation (HDO) is considered to be the most promising route to upgrade pyrolysis oil to liquid transportation fuels. The objective of this research was to explore inexpensive supported metal oxides/metal phosphide catalysts for the upgrading of pyrolysis oil into advanced drop-in hydrocarbon liquid fuels by HDO.

The first stage of this thesis project investigates a series of molybdenum oxides/phosphide catalysts on different supports that were prepared in-house, such as Al₂O₃, activated carbon (AC), MgAl₂O₄ and Mg₆Al₂(CO₃)(OH)₁₆. The HDO activity of these catalysts were investigated …

Mechanical Pretreatment Of Corncobs For Bioethanol Production By A Twin-Screw Extruder, Jun Zheng

Electronic Thesis and Dissertation Repository

Extrusion pretreatment of lignocellulosic biomasses is a physical continuous pretreatment method for subsequent fermentative ethanol production. Twin-screw elements (conveying, kneading and reverse) have different effects on enzymatic digestibility according to their geometries and functions. The first study evaluated the effects of individual functional screw elements on enzymatic digestibility and found that extrusion enhanced enzymatic digestibility under all tested condition. Reverse and kneading screw elements however resulted in lignin re-distribution over the cellulose fibres, blocked pores (shown via SEM) and resulted in less digestible biomass, compared to conveying screw elements, only. Lignin removal via NaOH reversed this effect and the highest …

The Effects Of Ocean Acidification And Eutrophication On The Growth, Lipid Composition And Toxicity Of The Marine Raphidophyte Heterosigma Akashiwo., Julia Rose Matheson

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Anthropogenic forcing, such as ocean acidification caused by rising carbon dioxide emissions, and eutrophication due to increased nutrient loadings in run-off, are causing major changes to the biogeochemistry of the oceans. As a consequence, coastal phytoplankton are susceptible to altered biogeochemical environments. This study examined the effect of a lower pH and increased levels of nutrients on the common coastal harmful alga, Heterosigma akashiwo. Growth rates, maximal cell yields, neutral lipid accumulation and toxicity of cells grown under various pH and nutrients regimes were measured. H. akashiwo growth was near maximal when grown at lower pH levels. There was …

Aging And Stabilization Of Pyrolitic Bio-Oils And Model Compounds, A. G. Manjula Taranganie Siriwardhana

Electronic Thesis and Dissertation Repository

When compared to conventional liquid fuels, bio-oil has several undesired properties such as high viscosity, high acidity, high molecular weight, instability, and phase separation upon aging. Therefore, bio-oil needs further stabilization and upgrading before it can be used as a fuel in engines. Phase separation is considered as one of the major issues because it is detrimental to any fuel application and creates problems in storage, transportation and upgrading of bio-oils. This thesis investigates the phase separation of hardwood derived bio-oil under accelerated aging conditions. Different alcohols are used as stabilizing agents and the minimum required amount of alcohol for …

Effect Of Plant Hormones On The Production Of Biomass And Lipid In Microalgae, Malihe Mehdizadeh Allaf

Electronic Thesis and Dissertation Repository

Limited fossil fuel reserves, increasing demand for energy in all parts of the world are some driving forces to look for new sources of transportation fuels. Among different options available, microalgae are currently attracting wide interests as an alternative and renewable fuel source.

Microalgae are single cell photosynthetic organisms that are known for rapid growth and high energy content and as a part of photosynthesis; they produce oil that can be used as a feedstock for biodiesel production. Some algae strains could contain lipid up to 80% of the dry biomass. The amount of lipid production is in direct relation …

Investigation Of Ash Deposition During Co-Firing Biomass/Peat With Coal In A Pilot-Scale Fluidized-Bed Reactor, Yuanyuan Shao

Electronic Thesis and Dissertation Repository

Biomass, a promising alternative to fossil fuels, has been applied widely for energy generation by co-firing technology in recent year particularly in the EU countries. In this thesis, a key issue of biomass co-firing technology - ash deposition in combustion, co-combustion and gasification, was comprehensively investigated in a pilot-scale bubbling fluidized bed reactor. A custom-designed, air-cooled probe was installed in the freeboard zone of the reactor to simulate the heat-transfer surface and collect ash deposits from the process. A local lignite coal, a woody biomass (white pine), and a Canadian peat were involved in the tests. The main varying operating …