Engineering Commons^™

System Analysis Of An Internal Combustion Engine (Ice) – Solid Oxide Fuel Cell (Sofc) Hybrid Cycle, Jose Javier Colon Rodriguez

Graduate Theses, Dissertations, and Problem Reports

Due to the intermittent nature of renewable energy and the rigid operation of existing coal plants, the need for flexible power generation technology is eminent. Hybrid energy systems have shown potential for flexible, grid following dynamics while maintaining higher efficiencies. The work below focuses on the performance analysis of a proposed 100 kW pressurized Internal Combustion Engine (ICE) and Solid Oxide Fuel Cell (SOFC) hybrid system. The un-utilized fuel from the SOFC stack provided the chemical energy to operate the engine. A turbocharger was used to deliver the necessary air flow for both the stack and engine. An external reformer …

Methane Emissions Produced By Pneumatic Devices And Produced Water Tanks On Natural Gas Wellsites, Benjamin William Thornton

Graduate Theses, Dissertations, and Problem Reports

Abstract

Methane Emissions Produced by Pneumatic Devices and Produced Water Tanks on Natural Gas Wellsites

Benjamin W. Thornton

In recent years, more scrutiny has been placed on the release of greenhouse gasses (GHGs) by the oil and gas industry in North America as climate concerns increase. In the coming years, stricter regulations proposed by the Environmental Protection Agency (EPA) concerning the release of GHGs will further direct attention to GHG emissions quantification, modeling, and overall reduction. Active natural gas wellsites employ production equipment that routinely emits methane during normal operation. Production equipment often includes, but is not limited to, gas …

Natural Gas Conversion To Value-Added Chemicals By Microwave Catalytic Processes, Brandon Robinson

Graduate Theses, Dissertations, and Problem Reports

Ethane is the second-largest component in natural gas and is typically separated out to minimize condensation in the pipelines. The technical difficulties and cost associated with the transportation and the storage of ethane have led companies to start burning natural gas to produce power or flaring which attributes to the global CO₂ emission problem. The conversion of ethane to higher-value liquid products is of increasing importance so that the natural gas can be safely utilized and cost-effectively transported. Existing commercial technologies used to convert ethane to liquid chemical products are typically based on the indirect syngas route, such as …

On The Improvement Of The Indirect Quantification Of Methane Emissions: A Stationary Single Sensor Approach, Robert Scott Heltzel

Graduate Theses, Dissertations, and Problem Reports

There is a need for improved indirect quantification of methane emissions, particularly from the natural gas industry. Natural gas production continues to increase along with the number of wells and production sites. These production sites have the potential to contribute significant levels of methane emissions. Methane is a potent greenhouse gas and the primary component of natural gas. A more complete understanding of emissions through improved quantification will lead to enhanced mitigation. Emissions have historically been quantified with both direct and indirect methods, with varying results. Emissions have been shown to be both temporally and spatially variable. These facts have …

Quantifying The Impact Of Load-Following On Gas-Fired Power Plants, Yifan Wang

Graduate Theses, Dissertations, and Problem Reports

Due to rapid penetration of renewables into the grid, natural gas combined cycle (NGCC) power plants are being forced to cycle their loads more frequently and rapidly than for which they were designed. However, the impact of load-following operation on plant efficiency and equipment health are currently poorly understood. The objective of this work is to quantify the impact of load-following on the gas-fired plants by developing high-fidelity multi-scale dynamic models. There are four main tasks in this project. First, dynamic model of an NGCC power plant has been developed. The main components of the NGCC plants are the gas …

Continuous Otm 33a Analysis Of Controlled Releases Of Methane With Various Time Periods, Data Rates And Wind Filters, Robert S. Heltzel, Mohammed T. Zaki, Aron K. Gebreslase, Omar I. Abdul-Aziz, Derek R. Johnson

Faculty & Staff Scholarship

Other test method (OTM) 33A has been used to quantify emissions from natural gas sites since it was introduced by the Environmental Protection Agency (EPA). The method relies on point source Gaussian (PSG) assumptions to estimate emissions rates from a targeted site or source. However, the method often results in low accuracy (typically ±70%, even under conducive conditions). These accuracies were verified with controlled-release experiments. Typically, controlled releases were performed for short periods (15–20 min) under atmospheric conditions that were ideal for effective plume transport. We examined three methane release rates from three distances over various periods of time ranging …

A Framework For Energy Optimization Of Small, Two-Stroke, Natural Gas Engines For Combined Heat And Power Applications, Mahdi Darzi

Graduate Theses, Dissertations, and Problem Reports

This research was focused on the development of a framework for the energy optimization a natural gas engine for small combined heat and power (CHP) applications operating with low-pressure natural gas (NG) available at homes. The required targets of the ARPA-E GENSETS program for 1 kW electric power generation and previous GENSETS simulation at West Virginia University, suggested a design space for the engine which is currently dominated by simple two-stroke designs. Hence this research focused on screening, modeling, and experimentally evaluation of cost-effective technologies to achieve a system design that maximized thermal efficiency and utilization factor, while reducing emissions. …

Experimental Design, Testing, And Evaluation Of Methods To Improve The Efficiency And Reduce Emissions From A Small Two-Stroke Natural Gas Engine, Christopher Joseph Ulishney

Graduate Theses, Dissertations, and Problem Reports

Decentralized power generation is a research area of interest due to possible improvements in electrical generation efficiency and grid resilience. Two-stroke engines are simple, inexpensive, power dense systems that could serve as the prime-movers for combined heat and power (CHP) systems. In addition, such systems could be fueled on natural gas (NG) that is readily available to serve as a reliable fuel source in most households. However, most two-stroke engines are inefficient and produce excessive emissions. This research focused on methods to simultaneously improve engine efficiency and decrease emissions from a 34 cc air-cooled, two-stroke engine retrofitted to operate on …

Investigation Of Combustion Characteristics Of A Heavy-Duty Diesel Engine Retrofitted To Natural Gas Spark Ignition Operation, Jinlong Liu

Graduate Theses, Dissertations, and Problem Reports

The conversion of existing diesel engines to natural-gas spark ignition operation by adding a gas injector in the intake manifold for fuel delivery and replacing the diesel fuel injector with a spark plug to initiate and control the combustion process can reduce U.S. dependence on petroleum imports and curtail engine-out emissions. As the conventional diesel combustion chamber (i.e., flat head and bowl-in-piston) creates high turbulence, the engine can operate leaner, which would increase its efficiency and reduce emissions. However, natural gas combustion in such retrofitted engines presents differences compared to that in conventional spark ignited engines. Subsequently, the main goal …