Engineering Commons^™

Development Of A Cold Model Fuild Coker Pilot Plant, Jessica A. Godin

Electronic Thesis and Dissertation Repository

Fluid Coking^TM is an upgrading process used to produce higher-value products from heavy hydrocarbons through thermal cracking. A Hot Pilot Plant is being designed for potential use to optimize commercial Fluid Cokers.

A Cold Model Fluid Coker was operated in this thesis to identify design limitations restricting operation at the required conditions. Design changes were implemented, and their impact on the system fluid dynamics were characterized. Successful operation of at required conditions was demonstrated.

Pressure measurements provided rapid feedback on potential issues. Models for bed expansion and entrainment flux were developed, which can be used to extrapolate to the …

Impact Of Local Fluidized Bed Hydrodynamics On The Distribution Of Liquid Sprayed Into The Bed, Yuan Li

Electronic Thesis and Dissertation Repository

In Fluid Coking, heavy oil is sprayed into a fluidized bed of hot coke particles that provide heat for the reaction and vaporization of the products, using nozzles located at different radial and axial locations of the reactor. In industrial units, imperfect initial liquid-solid contact results in the formation of wet agglomerates, which have been shown to cause fouling of the stripper sheds.

This thesis aims to reduce agglomerate formation by modifying the bed hydrodynamics in the spray region by adjusting the initial fluidization gas distribution or using a baffle.

Experimental methods were developed to study local gas flow, solids …

Mitigation Of Fouling And Liquid Losses In A Fluid Coker™: Influence Of Operating Conditions And Internals On Wet-Agglomerates Contribution To Liquid Carry-Under, Yohann Alain François Cochet

Electronic Thesis and Dissertation Repository

In Fluid Cokers, heavy oil is sprayed into a fluidized bed of hot particles through feed ring nozzles located at different heights. Unreacted or partially reacted feedstock, trapped in wet‑agglomerates, reaches the reactor bottom where it causes fouling or is lost to the system burner. The thesis objective is to determine whether modifying the feed distribution between rings or adding baffles can reduce the amount of liquid reaching the reactor bottom.

A model was developed to predict the amount of liquid reaching the reactor bottom. It integrates models for agglomerate formation and rewetting in spray jets, agglomerate drying through heat …

Thermodynamic Vapor-Liquid Equilibrium In Naphtha-Water Mixtures, Sandra Milena Lopez-Zamora

Electronic Thesis and Dissertation Repository

Naphtha is used to dilute the froth from bitumen treatment. Naphtha is recovered using a Naphtha Recovery Unit (NRU) and sent back to the froth dilution step. To minimize the environmental and economic impact of the NRU, it is imperative to maximize the naphtha recovery. It is, in this respect, that enhanced NRU Vapour-Liquid-Liquid equilibrium data is a significant value. The prediction of phase equilibria for hydrocarbon/water blends in separators, is a subject of considerable importance for chemical processes. Despite its relevance, there are still pending questions. Among them, is the prediction of the correct number of phases. While a …

Mitigation Of Fluid Coker Cyclone Fouling With Consideration To Reactor Performance, Andrew J. Heaslip

Electronic Thesis and Dissertation Repository

Fluid Coking is a continuous process to thermally upgrade heavy hydrocarbons into lighter, higher-value products. Fouling of the cyclones in commercial Fluid Coker reactors significantly reduces unit runtimes. The main objective of this thesis is to improve unit reliability by identifying process levers that can mitigate against this phenomenon while minimizing reductions in product quality. This thesis expanded a previous freeboard region model to consider vapour phase cracking and adsorption and developed a novel reactor region model to consider the impact of liquid and vapour phase cracking, vapour-liquid equilibrium, and residence time distribution on product composition. By changing the temperature …

Multiphase Equilibrium In A Novel Batch Dynamic Vl-Cell Unit With High Mixing: Apparatus Design And Process Simulation, Jeonghoon Kong

Electronic Thesis and Dissertation Repository

The availability of vapor pressure data is essential to validate thermodynamic models and enhance the thermodynamic correlations. Despite its importance, there is limited vapor pressure data of the multicomponent mixtures in open literature. This is the case for hydrocarbon/water blends as they are found in the naphtha recovery unit in the oil sand process.

This thesis uses a CREC-VL-Cell, a batch apparatus to measure the vapor pressures of n-octane/water, synthetic naphtha (SN)/water and solids/n-octane/water. The CREC-VL-Cell operates at thermal equilibrium with less than 1.6 % error using a 1080 rpm impeller speed and various optimized operational factors. This apparatus saves …

Bioremediation Of Refinery Desalter Effluent Using Debaryomyces Hansenii And Parachlorella Kessleri, Leila Azimian

Electronic Thesis and Dissertation Repository

Crude oil desalting operations produce an effluent stream which is challenging to treat due to its salt, heavy metal and hydrocarbon content. Consequently, desalter effluent (DE) is usually diluted into other effluent streams and sent to conventional wastewater treatment plants which may lead to upsets the plant operation.

In this study, a novel microbial approach was applied which investigated DE treatment using halotolerant yeast Debaryomyces hansenii (LAF-3 10 U) or the environmentally robust micro-algae Parachlorella kessleri strain CPCC 266. The effect of these two different approaches on both synthetic and actual DE was investigated in both batch and/or continuous mode. …

The Effect Of Scale On Spray Nozzle Performance, Aaron M. Joness

Electronic Thesis and Dissertation Repository

In the petroleum industry, Fluid Coker^TM are used to upgrade the heaviest remains of heavy oil into useful lighter products such as fuel oil or petrochemical feed. The development of a better injection into a Fluid Coker^TM is a key parameter to obtain a more efficient and sustainable use of heavy crude oil. The main detrimental factor in Fluid Coking^TM is the formation of agglomerates between the injected oil and the coke particles. These agglomerates not only trap injected oil, not allowing free reaction, but also cause harm to the Coker^TM when they fall to the …

Modeling Fluid Coker Cyclone Fouling, Erica Glatt

Electronic Thesis and Dissertation Repository

Fluid Coking^TM is a continuous process that thermally converts heavy hydrocarbons, such as oil-sands bitumen, to lighter and higher-value products by horizontal injection onto a fluidized bed of hot coke particles. The deposition of carbonaceous materials in the cyclone sections of commercial Fluid Cokers has been observed throughout each run. The main objective of this work is to improve unit reliability by proposing cyclone fouling mitigation strategies based on a localized phenomenological model using Aspen Plus®. The heavy ends condensation fouling mechanism was studied by incorporating vapour-liquid thermodynamics, thermal cracking reactions, and overall fluid dynamics in the Fluid Coker. …

Ultrasonic Techniques For Characterization Of Oil-Water Emulsion And Monitoring Of Interface In Separation Vessels, Embark Alshaafi

Electronic Thesis and Dissertation Repository

Emulsions created at different stages of crude oil production and processing present a number of problems and challenges. There is need to monitor emulsion layer in separation vessel to avoid its ingress into separated oil or water phases. It is also important to study role of different impurities and conditions on emulsion stability which determines the ease or difficulty on its breakup to separate the individual phases. There is also need to have a good understanding of emulsion rheology and effect of different variables on its flow behavior. There is currently a lack of suitable technique to monitor emulsion layer …

Development Of Ultrasonic Techniques For Characterization Of Liquid Mixtures, William A. Cooke

Electronic Thesis and Dissertation Repository

To evaluate the suitability of ultrasonic techniques for on-line process monitoring applications, an ultrasonic probe was used to measure acoustic velocity, acoustic impedance, and isentropic compressibility of hydrocarbons (including n-, iso-, and cycloalkanes, toluene, mineral oil, and crude oil) and polar liquids (alcohols, water, salt water) over a temperature range of 25-60°C. Temperature, carbon chain length, molecular shape, and intermolecular forces had significant effects on ultrasonic parameters. Relationships between media characteristics and observed ultrasonic parameters were modeled using empirical-least squares equations. The same parameters were measured in binary mixtures of hydrocarbons in heptane, as well as polar liquids in ethanol. …

Particle Entrainment Studies From Dry And Wet Bed, Saber Ayatollahi

Electronic Thesis and Dissertation Repository

During the Fluid Coking Process™ bitumen is sprayed into a fluidized bed of hot coke particles. The bitumen undergoes thermal cracking and is converted into gasses, condensable vapors, and solid coke, which deposits on the coke particles. These vapors rise through the vessel and result in entrainment of coke particles. Wet fine coke particles from the freeboard region enter the cyclone and contribute to the fouling of the Coker cyclones which can lead to the premature shut-down of Fluid Cokers.

The primary objective of this research is to determine how bed wetness affects entrainment.

First, a new fluidized bed was …

Application Of Treated Oil Sands Drill Cuttings Waste In Micropiles Construction, Moustafa Ahmed Raafat Mohamed Aboutabikh

Electronic Thesis and Dissertation Repository

A micropile is constructed by drilling a hole, placing a steel reinforcing element, grouting it using neat cement. However, cement production consumes energy and generates carbon dioxide. Implementing waste materials in construction applications represents a sustainable solution for many waste management problems. On the other hand, oil sands drill cuttings waste represents one of the most difficult challenges for the oil sands mining sector. Reducing the amount oil sands drill cutting waste sent to landfill offers one of the best solutions for waste management. This thesis presents an innovative solution for application of treated oil sands waste (TOSW) in grout …

Effect Of Spray Jet Interactions On The Liquid Distribution In A Fluidized Bed, Helal Elkolaly

Electronic Thesis and Dissertation Repository

Many processes use spray nozzles to introduce liquid into a fluidized bed. One such process is the Fluid Coking Process which is used to upgrade bitumen. Poor liquid distribution in a Fluid Coker proves detrimental as agglomerates form which introduce mass and heat transfer limitations. The main objective of this thesis is to determine the effect of interacting spray jets on the liquid distribution in a Fluid Coker. This was accomplished by using a low temperature experimental model of Fluid Coking to estimate the liquid distribution. Preliminary screening of nozzle positions was accomplished by the use of conductance measurements. A …

Cluster Fluid Dynamics In Down Flow Reactors: Experimental And Modeling Study, Angel Virgilio Lanza Soto

Electronic Thesis and Dissertation Repository

Gas–solid concurrent downers possess unique features when compared to other gas–solid systems. Establishing their fluid dynamic properties requires both experimental measurements of gas-solid flow properties and computational modeling.

Measuring gas-solid flow properties such as cluster solid concentrations, individual cluster slip velocities, and cluster sizes, involves the use of specialized optical equipment, as well as a rigorous data analysis methodology. In addition, the modeling of the fluid dynamics of gas-solid flows in downer units offers special challenges such as establishing a proper drag model, cluster configuration and sizes, sphericity, boundary conditions, among other issues.

In this PhD dissertation, the fluid dynamics …

Effects Of Mixing And Vapor Residence Time On The Thermal Cracking Performance Of Fluidized Beds, Clayton Stanlick

Electronic Thesis and Dissertation Repository

The objective of this thesis is to investigate the effects of applied bed mixing and vapor phase residence time on the thermal cracking of agglomerating and non-agglomerating feedstock. Bitumen thermal cracking was investigated using a novel Mechanically Fluidized Reactor system and a pilot-scale Fluid Coking Reactor. Bed mixing and vapor residence time were studied to determine their impacts on agglomerate distributions, yields, and the quality of liquid product. Birchwood pyrolysis was investigated using a fluidized bed reactor to determine the impacts of particle-bed mixing on the pyrolysis of a non-agglomerating feedstock, to provide contrast to the agglomerating bitumen-coke system. It …

Effect Of Nozzle Geometry On Jet Bed Interaction: Experiments With Commercial Scale Nozzles And Eroded Nozzles, Nicholas A. Prociw

Electronic Thesis and Dissertation Repository

Liquid injection into fluidized bed reactors has several industrial applications, such as Fluid Catalytic Cracking, Gas Phase Polyethylene production, and Fluid Coking. High quality liquid distribution is essential to maximize the yield of desirable products, and minimize agglomeration.

The objectives of this thesis are: to develop a method that measures the rate of liquid released from agglomerates formed as a result of liquid injection into a fluidized bed; to use this method to determine the effect of internal erosion on nozzle performance; and to compare the performance of current commercial spray nozzles to nozzles with altered geometries. To achieve these …

Hydrodynamics In Recirculating Fluidized Bed Mimicking The Stripper Section Of The Fluid Coker, Francisco J. Sanchez Careaga

Electronic Thesis and Dissertation Repository

The stripper section of a Fluid Coker^TM consists of a system of baffles (sheds) that enhances the removal of interstitial and adsorbed hydrocarbon vapors from the fluidized coke-particles. Most of the hydrocarbon-vapors released below a stripper shed flow up to the stripper shed, where they may crack and form coke deposits that foul the shed. Extensive fouling changes the shapes of the sheds, makes them thicker and reduces the free-space between the adjacent sheds until downward solids flow is so impaired that the Coker has to be shut down.

The Radioactive Particle Tracking (RPT) technique allows the determination of …

High Density Gas-Solids Circulating Fluidized Bed Riser And Downer Reactors, Chengxiu Wang

Electronic Thesis and Dissertation Repository

A systematic and comprehensive study of hydrodynamics and reactor performance was conducted in a 76 mm i.d., 10 m high riser and a 76 mm i.d., 5.8 m high downer reactor under high density/flux operating conditions using fluid catalytic cracking (FCC) catalyst particles. An optical fiber probe was used to obtain a complete mapping of local solids holdup and particle velocity. Catalytic ozone decomposition reaction was employed to study the characteristics of reactor performance in the CFB riser and downer. The superficial gas velocity (U_g) and the solids circulation rate (G_s) were 3-9 m/s …

Development And Application Of An Experimental Model For The Fluid Coking Process, Carolina B. Morales

Electronic Thesis and Dissertation Repository

Liquid injection into a fluidized bed is used in industrial applications such as the Fluid Coking^TM process for heavy oil thermal cracking. Poor initial liquid-solid contact results in the formation of agglomerates that limit heat and mass transfer processes, reduce the yield of valuable compounds and create operating problems. The present study develops a new experimental model to simulate the complex phenomena that occur when heavy oil is injected in a Fluid Coker through two-phase nozzles. The model is applied in a pilot scale fluidized bed using scaled-down industrial spray nozzles. The experimental results indicate that agglomerate formation slows …

A Novel Mixed Metallic Oxygen Carrier For Chemical Looping Combustion: Preparation, Characterization And Kinetic Modeling, Mohammad Rezwanul Quddus

Electronic Thesis and Dissertation Repository

In last decades, significant concerns have been raised regarding the global warming effect. To date, about one-third of the total anthropogenic CO₂ emission results from power generation using fossil based fuel and CO₂ is the main contributor to global warming. Therefore, technologies for efficient capture of CO₂ are becoming of great value. In this respect, Chemical-Looping Combustion (CLC) has received significant attention as a promising technology facilitating concurrent CO₂ capture and power generation. This non-conventional technique employs a solid carrier, known as oxygen carrier, to supply oxygen and facilitates combustion process in absence of N_{2 …}

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 …

Simultaneous Particle Agglomeration And Attrition In A High Temperature Fluidized Bed, Mithun Saha

Electronic Thesis and Dissertation Repository

Fluid Coking^TM is a major refining process to upgrade heavy crude oil or bitumen from oil sands. In Fluid Coking^TM bitumen is atomized with steam and sprayed inside a high temperature fluidized bed of coke particles where it thermally cracks into smaller molecules. Fluid Coking^TM is a carbon rejection process as solid carbon residues are formed during fragmentation into lighter hydrocarbon vapors. New coke deposits over existing coke particles and, consequently, the particle size increases. In addition, particles agglomeration occurs when the injected liquid does not disperse uniformly on individual hot coke particles but reaches, instead, local …

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 …

Particle Attrition With Supersonic Nozzles In A High Temperature Fluidized Bed, Feng Li

Electronic Thesis and Dissertation Repository

Fluidized beds are widely used for a variety of processes such as food, pharmaceutical, petrochemical and energy production. As a typical application of fluidized beds, the fluid coking process uses thermal cracking reactions to upgrade heavy oils and bitumen from oil sands. In order to maintain a well fluidized bed and a satisfactory operation, a series of supersonic nozzles are used to inject high pressure steam in the bed to maintain the coke particle within an optimal range. Currently, the attrition nozzles consume a large florwrate of high pressure and superheated steam, which accounts for about 40 % of the …