Model-Based Thermodynamic Analysis of a Hydrogen-Fired Gas Turbine With External Exhaust Gas Recirculation

In a carbon constrained world there is a need for capturing and sequestering CO2. Post-combustion carbon capture via Exhaust Gas Recirculation (EGR) is considered a feasible means of reducing emission of CO2 from power plants. Exhaust Gas Recirculation is an enabling technology for increasing the CO2 concentration within the gas turbine cycle and allow the decrease of the size of the separation plant, which in turn will enable a significant reduction in CO2 capture cost. This paper describes the experimental work performed to better understand the risks of utilizing EGR in combustors employing dry low emissions (DLE) technologies. A rig was built for exploring the capability of premixers to operate in low O2 environment, and a series of experiments in a visually accessible test rig was performed at representative aeroderivative gas turbine pressures and temperatures. Experimental results include the effect of applying EGR on operability, efficiency and emissions performance under conditions of up to 40% EGR. Findings confirm the viability of EGR for enhanced CO2 capture; In addition, we confirm benefits of NOx reduction while complying with CO emissions in DLE combustors under low oxygen content oxidizer.

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Study of Using Exhaust Gas Recirculation on a Gas Turbine for Carbon Capture

Volume 5: Controls, Diagnostics, and Instrumentation; Cycle Innovations; Cycle Innovations: Energy Storage ◽

10.1115/gt2020-16080 ◽

2020 ◽

Author(s):

Dan Burnes ◽

Priyank Saxena ◽

Paul Dunn

Keyword(s):

Gas Turbine ◽

Gas Turbines ◽

Carbon Capture ◽

Hydrocarbon Fuel ◽

Exhaust Gas Recirculation ◽

Exhaust Gas ◽

Hybrid Solutions ◽

Industrial Gas Turbines ◽

Industrial Gas Turbine ◽

Gas Recirculation

Abstract The growing call of minimizing carbon dioxide and other greenhouse gases emitting from energy and transportation products will spur innovation to meet new stringent requirements while striving to preserve significant investments in the current infrastructure. This paper presents quantitative analysis of exhaust gas recirculation (EGR) on industrial gas turbines to enable carbon sequestration venturing towards emission free operation. This study will show the effect of using EGR on gas turbine performance and operation, combustion characteristics, and demonstrate potential hybrid solutions with detailed constituent accounting. Both single shaft and two shaft gas turbines for power generation and mechanically driven equipment are considered for application of this technology. One key element is assessing the combustion system operating at reduced O2 levels within the industrial gas turbine. With the gas turbine behavior operating with EGR defined at a reasonable operating state, a parametric study shows rates of CO2 sequestration along with quantifying supplemental O2 required at the inlet, if needed, to sustain combustion. With rates of capture known, a further exploration is examined reviewing potential utilities, monetizing these sequestered constituents. Ultimately, the objective is to preview a potential future of operating industrial gas turbines in a non-emissive and in some cases carbon negative manner while still using hydrocarbon fuel.

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Effects of SOFC Exhaust Gas Recirculation on Performance of Solid Oxide Fuel Cell-Gas Turbine Hybrid System Utilizing Renewable Fuels

ECS Meeting Abstracts ◽

10.1149/ma2015-03/1/47 ◽

2015 ◽

Keyword(s):

Fuel Cell ◽

Solid Oxide Fuel Cell ◽

Gas Turbine ◽

Hybrid System ◽

Exhaust Gas Recirculation ◽

Solid Oxide ◽

Renewable Fuels ◽

Exhaust Gas ◽

Oxide Fuel ◽

Gas Recirculation

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A thermodynamic analysis of the use of exhaust gas recirculation in spark ignition engines including the second law of thermodynamics

Proceedings of the Institution of Mechanical Engineers Part D Journal of Automobile Engineering ◽

10.1243/09544070jauto935 ◽

2009 ◽

Vol 223 (1) ◽

pp. 131-149 ◽

Cited By ~ 26

Author(s):

R G Shyani ◽

J A Caton

Keyword(s):

Thermodynamic Analysis ◽

Second Law Of Thermodynamics ◽

Exhaust Gas Recirculation ◽

Spark Ignition ◽

Second Law ◽

Exhaust Gas ◽

Spark Ignition Engines ◽

Gas Recirculation

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Investigation of a Generic Gas Turbine Combustor With Exhaust Gas Recirculation

Volume 1A: Combustion, Fuels and Emissions ◽

10.1115/gt2013-94678 ◽

2013 ◽

Author(s):

Sebastian Ulmer ◽

Franz Joos

Keyword(s):

Heat Release ◽

Gas Turbine ◽

Co2 Capture ◽

Release Rate ◽

Exhaust Gas Recirculation ◽

Exhaust Gas ◽

Nitric Oxides ◽

Gas Turbine Combustor ◽

A Minor ◽

Gas Recirculation

On the topic of CO2 capture from gas turbines, exhaust gas recirculation (EGR) is a commonly discussed method to increase CO2 concentration at a gas turbine outlet to make the CO2 capture process more efficient. This paper presents the influence of the recirculation on heat release rate and emissions. The investigation is made using the commercial RANS solver ANSYS CFX coupled with an in-house code for a hybrid transported PDF/RANS simulation using detailed chemistry of GRI 3.0. Initially an investigation on reactivity was made using numerical calculation of laminar flame speed. It is found that exhaust gas recirculation has only a minor effect on reactivity in lean premixed combustion. Therefore, the operation point of the combustor can be kept constant with and without EGR. Simulations of the combustor with exhaust gas recirculation using the hybrid PDF/RANS with GRI 3.0 show a minor influence of NO and NO2 doping of the vitiated air on the flame speed and the doping delays heat release slightly. CO doping has no effect on heat release rate. CO emissions at combustor exit remain unaffected by NO, CO or NO2 doping. Seeding the vitiated air with 50ppm nitric oxides reveal that any NO2 present in the vitiated air is reduced to NO in the flame. NO2 emissions increase with NO2 doping but are still 2 magnitudes lower than NO emissions. It is found that NO is reduced by 3% due to of NO reburn. Based on literature data it is concluded that there is a deficit of the GRI 3.0 reaction mechanism. Experimental data taken from literature reveal of NO reburn by approximately 20%. Therefore emission data of nitric oxides of flames that should show a considerable reburn effect should be used with caution, while heat release and CO emissions are predicted more accurately. It is shown, that with the model created for the generic gas turbine combustor it is possible to study the effects of exhaust gas recirculation on the combustion process in detail and resolve detailed kinetic effects.

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