Other Chemical Engineering Commons^™

Effect Of Liquid-Solid Contact On Thermal Cracking Of Heavy Hydrocarbons In A Mechanically Fluidized Reactor, Mitesh C. Chaudhari

Electronic Thesis and Dissertation Repository

The aim of the thesis was to study the effect of liquid-solid contact on the thermal cracking of heavy hydrocarbons carried out in Fluid Cokers. The research has been carried out using a Mechanically Fluidized Reactor (MFR) in which the operating conditions of the Fluid Coking^TM reactions can be simulated and monitored. The first part of the research, aimed at investigating the effect of agitation on liquid-solid contact, which was carried out by changing the rotation speed of the agitator of the MFR for both non-reactive as well as for reactive systems. In both situations, it was observed that …

Fractional Condensation Of Bio-Oil Vapors, Akhil Tumbalam Gooty

Electronic Thesis and Dissertation Repository

The research project described in this thesis deals with an investigation on the fractional condensation of bio-oil vapors to improve the separation of some of the key components of the bio-oil and, consequently, improve the properties and the value of each of the separated product streams.

In the first part, the separation of a mixture of three model compounds of bio-oil from a vapor and carrier gas stream was investigated with the help of a series of three condensers maintained at different temperatures. The practical performance of the fractional condensation train was improved by comparing the experimental results with the …

Production Of Bio-Coal And Activated Carbon From Biomass, Diana C. Cruz

Electronic Thesis and Dissertation Repository

The slow pyrolysis of different biomasses (maple wood, birch bark, switch grass, coffee pulp and corn stalk) was studied with the aim to produce a solid pyrolysis product (bio-coal) with promising properties and potential for use in traditional fossil-coal applications. Batch pyrolysis experiments were conducted in a Mechanically Fluidized Reactor (MFR) at temperatures ranging from 143 to 665 ^oC, which includes the torrefaction temperature range (200-300 ^oC). The effects of temperature and holding time on bio-coal mass yields were determined. The bio-coals were characterized in detail and a highly-controlled study on bio-coal hygroscopicity is presented. Optimal conditions for …

Preparation And Formulation Of Powder Coating For Application Of Enamelled Wire, Liuyin Xia

Electronic Thesis and Dissertation Repository

Enamelled wire is a conductive wire coated with a very thin layer of insulation, widely used in the field that requires tight coils of wire. The traditional enamelled wire is produced by liquid paint, which consists of resins, solvents, pigments, and additives. Organic solvent takes a relatively high content, normally of 75% to 90% by weight. Many efforts have been made to decrease the percentage of solvent in the insulation paint. On the other hand, increasing the solids content of given enamel results in the viscosity rises significantly, making it harder to flow. Therefore, powder coating technology as an alternative …

Calcium Phosphate-Based Resorbable Biomaterials For Bone Regeneration, Daniel O. Costa

Electronic Thesis and Dissertation Repository

Bone defects are a prevalent problem in orthopedics and dentistry. Calcium phosphate-based coatings and nanocomposites offer unique solutions towards producing scaffolds with suitable physical, mechanical and biological properties for bone regeneration.

We developed a novel method to synthesize hydroxyapatite (HA) particles with high aspect ratio using sol-gel chemistry and hydrothermal treatment. We obtained tunable pure-phase carbonated-HA in the form of micro/nanorods and nanowires (diameters 25-800 nm). To mimic the structure of bone, HA nanowires were homogenously mixed within poly(ε-caprolactone) (PCL) to produce nanocomposites with improved mechanical properties as determined by uniaxial tensile testing.

Surface chemistry and topography of biomaterials play …

Improved Non-Linear Solution Of Dip Coating Flow, Omar Bin Yusuf

Electronic Thesis and Dissertation Repository

A thin layer of film is developed on the surface of a substrate in the dip coating process where the substrate is initially immersed into the coating fluid and then withdrawn continuously from the coating fluid bath. In this study a two dimensional flow of the thin film for a Newtonian fluid is examined theoretically by dividing the film into three separate regions. A general formulation is developed for a thin film flow, which then simplifies for each region upon considering appropriate assumptions to each region. The influence of inertia and surface tension in the presence of gravity is investigated …

Experimental & Empirical Correlations For The Determination Of The Overall Volumetric Mass Transfer Coefficients Of Carbon Dioxide In Stirred Tank Bioreactors, Syeda Anam Kazim

Electronic Thesis and Dissertation Repository

One of the most important parameters to cultivate microalgae is carbon dioxide absorption by microalgae. Therefore, it is necessary to determine the overall volumetric mass transfer coefficient (K_La) of carbon dioxide to quantify CO₂ transfer from the gaseous to the liquid phase. Until now, finding K_La of CO₂ for microalgae cultivation has been a challenge as there is not much information available about it in the literature and most of the time the CO₂ transfer to microalgae is approximated. In this study, correlations to directly calculate K_La of CO₂ in …

Liquid Distribution From Industrial Scale Spray Jets In Fluidized Beds, Mohammadali Zirgachianzadeh

Electronic Thesis and Dissertation Repository

Liquid injections via spray nozzles are used in fluidized bed reactors such as Fluid Cokers. In such industrial processes, in order to maximize the product yields it is required to optimize the performance of the nozzle. Moreover parts of the bed might become defluidized, bogged, due to high liquid load. Then optimizing the performance of the nozzle and local bed bogging detection is the primary research objectives for this thesis work.

The first part of the research work was focused on developing a novel method employing electrical conductance to characterize the liquid distribution in a large scale fluid bed of …

Developing Novel Methods To Characterize Liquid Dispersion In A Fluidized Bed, Masoumeh Farkhondehkavaki

Electronic Thesis and Dissertation Repository

The performance of several important industrial processes, such as fluid coking or fluid catalytic cracking, is dependent on the good distribution of liquid feed sprayed into a fluidized bed of hot inert or catalytic particles, respectively.

Liquid injected into a fluidized bed is distributed in three different ways: (i) free moisture, or liquid coating individual particles; (ii) wet micro-agglomerates, which are fluidized; and (iii) wet macro-agglomerates, which settle to the bottom of the bed. This study develops and evaluates various methods for the determination of this moisture.

In the study using electrical techniques, two different kinds of electrodes geometries are …

Oxygen Delivery Strategies In Tissue-Engineering Constructs, Dawit Gezahegn Seifu

Electronic Thesis and Dissertation Repository

The supply of nutrients and the removal of waste products play a major role in tissue engineering. From all the nutrients necessary for cells seeded on scaffolds for tissue regeneration, oxygen is the limiting component due to its low solubility in culture media while cells consume five to six moles of oxygen for every mole of monosaccharide. The aim of the present work was to develop different strategies to improve the supply of oxygen to human coronary artery smooth muscle cells (HCASMC) seeded on three dimensional (3D) porous biostable polyurethane scaffolds. As a springboard for the study, the measured value …