Techno-economic Comparison of Combined Cycle Gas Turbines with Advanced Membrane Configuration and Monoethanolamine Solvent at Part Load Conditions

Abstract EPRI has been developing a digital twin of simple and combined cycle gas turbines over the last 5+ years to provide owners and operators with improved capabilities that typically reside in the expert domain of OEMs and 3rd party service providers. The digital twin is a digital model, a physics-based representation of the actual asset. The model is thermodynamic and is created with the intent to support 5 M&D areas: • Integrate with existing M&D tools such as advanced pattern recognition (APR) • Power plant performance prediction and trending such as day, week, and month ahead performance prediction for capacity and generation planning • Health Monitoring and Fault Diagnostics to support asset management with additional health scores and virtual instrumentation enabled by the digital twin model • Monitoring and prediction of both base and part-load performance. Many gas turbine tools have been simplified to work only at full load conditions. To be useful and to improve utilization of collected data, part-load conditions should also be considered. • Outage and repair impacts, including “what-if” capability to understand and quantify potential root causes of less than expected performance improvement or recovery after outage and repairs. This paper presents current progress in creating an EPRI Digital Twin applicable to gas turbines. The formulation, methodology, and real-world use cases are presented. To date, digital twins have been created and tested for both E and F class frames. This paper describes the process of generating closed-form equations capable of transforming existing, measured historian data into the health parameters and virtual sensors needed to better track unit health and monitor faulted performance. These equations encapsulate the digital twin physical model and provide end-users with a methodology to calibrate to their specific unit and efficiently use their choice of monitoring software. Tests have been performed using operator data and have shown good accuracy at detecting anomalous operation and predicting week ahead performance with excellent accuracy. Post-outage impact analysis is also assessed. Real-world application cases for the digital twin are also presented. Examples include using the digital twin to identify causes of post-outage emissions and performance issues, expected impact of degradation and fault conditions, and simulating improvements to operation through part repair and upgrades.

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Part-Load Operation of Gas Turbines Induced by Co-Gasification of Coal and Biomass in an Integrated Gasification Combined Cycle Power Plant

10.1115/gt2021-59830 ◽

2021 ◽

Author(s):

Silvia Ravelli

Keyword(s):

Power Plant ◽

Gas Turbines ◽

Combined Cycle ◽

Inlet Guide Vane ◽

Inlet Temperature ◽

Fuel Quality ◽

Integrated Gasification Combined Cycle ◽

Part Load ◽

Wide Range ◽

Integrated Gasification

Abstract This study takes inspiration from a previous work focused on the simulations of the Willem-Alexander Centrale (WAC) power plant located in Buggenum (the Netherlands), based on integrated gasification combined cycle (IGCC) technology, under both design and off-design conditions. These latter included co-gasification of coal and biomass, in proportions of 30:70, in three different fuel mixtures. Any drop in the energy content of the coal/biomass blend, with respect to 100% coal, translated into a reduction in gas turbine (GT) firing temperature and load, according to the guidelines of WAC testing. Since the model was found to be accurate in comparison with operational data, here attention is drawn to the GT behavior. Hence part load strategies, such as fuel-only turbine inlet temperature (TIT) control and inlet guide vane (IGV) control, were investigated with the aim of maximizing the net electric efficiency (ηel) of the whole plant. This was done for different GT models from leading manufactures on a comparable size, in the range between 190–200 MW. The influence of fuel quality on overall ηel was discussed for three binary blends, over a wide range of lower heating value (LHV), while ensuring a concentration of H2 in the syngas below the limit of 30 vol%. IGV control was found to deliver the highest IGCC ηel combined with the lowest CO2 emission intensity, when compared not only to TIT control but also to turbine exhaust temperature control, which matches the spec for the selected GT engine. Thermoflex® was used to compute mass and energy balances in a steady environment thus neglecting dynamic aspects.

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Degradation analysis of a combined cycle heat recovery steam generator under full and part load conditions

Sustainable Energy Technologies and Assessments ◽

10.1016/j.seta.2019.100587 ◽

2020 ◽

Vol 37 ◽

pp. 100587 ◽

Cited By ~ 1

Author(s):

Yousef S.H. Najjar ◽

Osama F.A. Alalul ◽

A. Abu-Shamleh

Keyword(s):

Steam Generator ◽

Heat Recovery ◽

Combined Cycle ◽

Heat Recovery Steam Generator ◽

Part Load ◽

Degradation Analysis ◽

Load Conditions

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Gas Turbine Part Load Performance Testing: Comparison of Test Methodologies

ASME 2008 Power Conference ◽

10.1115/power2008-60036 ◽

2008 ◽

Cited By ~ 1

Author(s):

Thomas P. Schmitt ◽

Herve Clement

Keyword(s):

Gas Turbine ◽

Gas Turbines ◽

Guide Vane ◽

Performance Testing ◽

Load Level ◽

Combined Cycle ◽

Inlet Guide Vane ◽

Performance Guarantee ◽

Part Load ◽

Advantages And Disadvantages

Current trends in usage patterns of gas turbines in combined cycle applications indicate a substantial proportion of part load operation. Commensurate with the change in operating profile, there has been an increase in the propensity for part load performance guarantees. When a project is structured such that gas turbines are procured as equipment-only from the manufacturer, there is occasionally a gas turbine part load performance guarantee that coincides with the net plant combined cycle part load performance guarantee. There are several methods by which to accomplish part load gas turbine performance testing. One of the more common methods is to operate the gas turbine at the specified load value and construct correction curves at constant load. Another common method is to operate the gas turbine at a specified load percentage and construct correction curves at constant percent load. A third method is to operate the gas turbine at a selected load level that corresponds to a predetermined compressor inlet guide vane (IGV) angle. The IGV angle for this third method is the IGV angle that is needed to achieve the guaranteed load at the guaranteed boundary conditions. The third method requires correction curves constructed at constant IGV, just like base load correction curves. Each method of test and correction embodies a particular set of advantages and disadvantages. The results of an exploration into the advantages and disadvantages of the various performance testing and correction methods for part load performance testing of gas turbines are presented. Particular attention is given to estimates of the relative uncertainty for each method.

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Development of a Catalytic Combustor for Industrial Gas Turbines

Volume 3: Coal, Biomass and Alternative Fuels; Combustion and Fuels; Oil and Gas Applications; Cycle Innovations ◽

10.1115/94-gt-254 ◽

1994 ◽

Cited By ~ 2

Author(s):

Luke H. Cowell ◽

Matthew P. Larkin

Keyword(s):

Gas Turbines ◽

Catalytic Combustion ◽

Nox Emissions ◽

Combustion System ◽

Single Digit ◽

Design Elements ◽

Part Load ◽

Lean Premixed ◽

Industrial Gas Turbines ◽

Load Conditions

A catalytic combustion system for advanced industrial gas turbines is under long tern development employing recent advances in catalyst and materials technologies. Catalytic combustion is a proven means of burning fuel with single digit NOx emissions levels. However, this technology has yet to be considered for production in an industrial gas turbine for a number of reasons including: limited catalyst durability, demonstration of a system that can operate over all loads and ambient conditions, and market and cost factors. The catalytic combustion system will require extensive modifications to production gas turbines including fuel staging and variable geometry. The combustion system is composed of five elements: a preheat combustor, premixer, catalyst bed, part load injector and post-catalyst combustor. The preheat combustor operates in a lean premixed mode and is used to elevate catalyst inlet air and fuel to operating temperature. The premixer combines fuel and air into a uniform mixture before entering the catalyst. The catalyst bed initiates the fuel-air reactions, elevating the mixture temperature and partially oxidizing the fuel. The part load injector is a lean premixed combustor system that provides fuel and air to the post-catalyst combustor. The post-catalyst combustor is the volume downstream of the catalyst bed where the combustion reactions are completed. At part load conditions a conventional flame bums in this zone. Combustion testing is on-going in a subscale rig to optimize the system and define operating limits. Short duration rig testing has been completed to 9 atmospheres pressure with stable catalytic combustion and NOx emissions down to the 5 ppmv level. Testing was intended to prove-out design elements at representative full load engine conditions. Subscale combustion testing is planned to document performance at part-load conditions. Preliminary full-scale engine design studies are underway.

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Part Load Operation of a Multiple-Injection Dry Low NOx Combustor on Hydrogen-Rich Syngas Fuel in an IGCC Pilot Plant

Volume 4A: Combustion, Fuels and Emissions ◽

10.1115/gt2015-42312 ◽

2015 ◽

Cited By ~ 3

Author(s):

Tomohiro Asai ◽

Satoschi Dodo ◽

Mitsuhiro Karishuku ◽

Nobuo Yagi ◽

Yasuhiro Akiyama ◽

...

Keyword(s):

Power Systems ◽

Pilot Plant ◽

Gas Turbines ◽

Combustion Efficiency ◽

Combined Cycle ◽

Multiple Injection ◽

Load Range ◽

Part Load ◽

Combustion Of Hydrogen ◽

Initial Staging

The successful development of coal-based integrated gasification combined cycle (IGCC) technology requires gas turbines capable of achieving the dry low-nitrogen oxides (NOx) combustion of hydrogen-rich syngas for low emissions and high plant efficiency. Mitsubishi Hitachi Power Systems, Ltd. (MHPS) has been developing a “multiple-injection combustor” to achieve the dry low-NOx combustion of hydrogen-rich syngas. This study suggests an advanced fuel staging comprising a hybrid partial combustion mode to improve the combustor’s part load performance. The purposes of this paper are to present the test results of the combustor with the advanced staging on a syngas fuel in an IGCC pilot plant, and to evaluate its performance. The syngas fuel produced in the plant contained approximately 50% carbon monoxide, 20% hydrogen, and 20% nitrogen by volume. In the test, the advanced staging reduced the maximum NOx at part load to 44 ppm (at 15% oxygen) compared with the initial staging with a maximum NOx of 75 ppm, and attained higher combustion efficiency above 98.7% over the part load range than the initial staging with combustion efficiency above 97.1%. In conclusion, the advanced staging improved the part load performance by achieving lower NOx emissions and higher combustion efficiency.

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