ORCID Identifier(s)

0000-0002-9677-8719

Graduation Semester and Year

2019

Language

English

Document Type

Dissertation

Degree Name

Doctor of Philosophy in Mechanical Engineering

Department

Mechanical and Aerospace Engineering

First Advisor

Brian Dennis

Abstract

Gas to Liquid (GTL) processes chemically convert natural gas to valuable liquid hydrocarbon products. The GTL process considered in this research is comprised of three phases: 1) syngas production, 2) Fischer-Tropsch synthesis (FTS), and 3) product separation. This study focuses on the simulation and optimization of a GTL process to convert natural gas to more valuable liquid fuels. In syngas production, steam methane reforming (SMR) is typically used although it requires an external heat source due to the endothermic nature of the reaction. In addition, the SMR approach produces syngas with a hydrogen to carbon monoxide ratio that is not ideal for the FTS reaction. An alternative approach that combines partial oxidation of methane (POX) and SMR in series is considered in this work. The heat released in the exothermic POX stage drives the endothermic SMR stage resulting in an auto-thermal reforming reaction (ATR) that is net exothermic. The resulting syngas product has the ideal hydrogen to carbon monoxide ratio for FTS. The aim of this work is to establish numerical models for the ATR and FTS reactor components of a GTL plant and study the impact of various input parameters on the output of the overall system. Kinetic models were developed based on laboratory data collected from a GTL pilot plant operating at UTA. A multiphysics finite element model was developed to simulate a multi tubular packed bed reactor for FTS. The impact of coolant flow rate and syngas space velocity on oil productivity and syngas conversion was studied.

Keywords

GTL, FTS

Disciplines

Aerospace Engineering | Engineering | Mechanical Engineering

Comments

Degree granted by The University of Texas at Arlington

Download

Share

COinS