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Cyclic Sequential Adsorption Desorption/Thermal-Catalytic Oxidation Of Volatile Organic Compounds: Material Development, Process Advancement/Improvement, And Numerical Modeling, Simulation And Optimization, Busuyi Ojo Adebayo

Doctoral Dissertations

"Volatile organic compounds (VOCs) are a group of useful organic chemicals but when emitted have contributed to air pollution. They affect human health, cause environmental degradation and contaminate our waters and soils, so they need to be controlled. When they exist in dilute concentrations, abatement becomes challenging, thus requiring advanced abatement methods, e.g., sequential adsorption desorption/thermal-catalytic oxidation process. The overall goal of this research was to abate dilute streams of VOCs via the process. The specific objectives were to 1) develop novel adsorbent/catalyst dual-function materials (DFMs) for the process, 2) improve the operability of a one-bed-one-column reactor configuration for the …

Transient Multiphase Flow Simulation For Unloading Of Frac Hit Gas Wells, Miguel Angel Cedeno Moreno

Doctoral Dissertations

"This work seeks to develop a fully step-by-step transient multiphase flow simulation valid for unloading gas wells using nitrogen. It studies the behavior of nitrogen for unloading horizontal gas wells with gas injection in the annulus. The work investigates unloading non-Newtonian fluids such as those which invade offset wells when a frac hit occurs during hydraulic fracturing operations in unconventional wells. The effect of varying tubing depth and injection pressure are included in the study.

Results show that as the plastic viscosity increases, the nitrogen volume and time to unload will be increased. As tubing depth increases, the nitrogen volume …

Multiscale Modeling Of Electrolytes For Energy Storage And Conversion, Fatemeh Sepehr

Doctoral Dissertations

Fuel cells, redox flow batteries, and secondary ion batteries are under active investigation to fulfill the requirements of efficient and sustainable energy storage and conversion technologies. The discovery of high-performance stable electrolytes that are relatively cheap and versatile is crucial to the commercialization of these electrochemical devices and necessitates a comprehensive understanding of the materials (i.e., from the atomistic to continuum levels). This dissertation is on multiscale modeling and simulations of several electrolytes under consideration in vanadium redox flow batteries (VRFBs), alkaline fuel cells (AFCs), or secondary magnesium batteries.

The hydrated structure and associated solvation Gibbs energies were determined for …

Multi-Scale Simulation Of Linear, Short-Chain Polyethylene Liquids Under Flow Conditions, Jun Mo Kim

Doctoral Dissertations

The rheological and structural properties of polymeric liquids cannot be condensed within a single numerical model. They should be described within hierarchical, multi-level numerical models in which each sub-model is responsible for different time and length scales; atomistic, mesoscopic, and continuum. In this study, the rheological and structural properties of linear, short-chain polyethylene liquids were investigated from the classical atomistic level to the mesoscopic and continuum levels of description. At the atomistic level of description, nonequilibrium molecular dynamics (NEMD) simulations of linear, short-chain polyethylene liquids spanning from C16H24 to C128H256 were performed to advance our knowledge of fundamental characteristic of …