Design and Initial Development of Monolithic Cross-Flow Ceramic Hot-Gas Filters

Advanced, coal-fueled, power generation systems utilizing pressurized fluidized bed combustion (PFBC) and integrated gasification combined cycle (IGCC) technologies are currently being developed for high-efficiency, low emissions, and low-cost power generation. In spite of the advantages of these promising technologies, the severe operating environment often leads to material degradation and loss of performance in the barrier filters used for particle entrapment. To address this problem, LoTEC Inc., and Oak Ridge National Laboratory are jointly designing and developing a monolithic cross-flow ceramic hot-gas filter. The filter concept involves a truly monolithic cross-flow design that is resistant to delamination, can be easily fabricated, and offers flexibility of geometry and material make-up. During Phase I of the program, a thermo-mechanical analysis was performed to determine how a cross-flow filter would respond both thermally and mechanically to a series of thermal and mechanical loads. The cross-flow filter mold was designed accordingly, and the materials selection was narrowed down to Ca0.5Sr0.5Zr4P6O24 (CS-50) and 2Al2O3−3SiO2 (mullite). A fabrication process was developed using gelcasting technology and monolithic cross-flow filters were fabricated. The program focuses on obtaining optimum filter permeability and testing the corrosion resistance of the candidate materials.

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Development of Ceramic Composite Hot-Gas Filters

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

10.1115/95-gt-305 ◽

1995 ◽

Author(s):

Roddie R. Judkins ◽

David P. Stinton ◽

Robert G. Smith ◽

Edward M. Fischer ◽

Joseph H. Eaton ◽

...

Keyword(s):

National Laboratory ◽

Combined Cycle ◽

Ceramic Fiber ◽

Fluidized Bed Combustion ◽

Integrated Gasification Combined Cycle ◽

Oak Ridge ◽

Hot Gas ◽

The Status ◽

Integrated Gasification ◽

Pressurized Fluidized Bed Combustion

A novel type of hot-gas filter based on a ceramic fiber-reinforced ceramic matrix was developed and extended to full-size, 60-mm OD by 1.5-meter-long, candle filters. A commercially viable process for producing the filters was developed, and the filters are undergoing testing and demonstration throughout the world for applications in pressurized fluidized-bed combustion (PFBC) and integrated gasification combined cycle (IGCC) plants. Development activities at Oak Ridge National Laboratory (ORNL) and at the 3M Company, and testing at the Westinghouse Science and Technology Center (STC) are presented. Demonstration tests at the Tidd PFBC are in progress. Issues identified during the testing and demonstration phases of the development are discussed. Resolution of the issues identified during testing and the status of commercialization of the filters are described.

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Development of Ceramic Composite Hot-Gas Filters

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.2816675 ◽

1996 ◽

Vol 118 (3) ◽

pp. 495-499 ◽

Cited By ~ 7

Author(s):

R. R. Judkins ◽

D. P. Stinton ◽

R. G. Smith ◽

E. M. Fischer ◽

J. H. Eaton ◽

...

Keyword(s):

National Laboratory ◽

Combined Cycle ◽

Ceramic Fiber ◽

Fluidized Bed Combustion ◽

Integrated Gasification Combined Cycle ◽

Oak Ridge ◽

Hot Gas ◽

The Status ◽

Integrated Gasification ◽

Pressurized Fluidized Bed Combustion

A novel type of hot-gas filter based on a ceramic fiber-reinforced ceramic matrix was developed and extended to full-size, 60-mm OD by 1.5-m-long, candle filters. A commercially viable process for producing the filters was developed, and the filters are undergoing testing and demonstration throughout the world for applications in pressurized fluidized-bed combustion (PFBC) and integrated gasification combined cycle (IGCC) plants. Development activities at Oak Ridge National Laboratory (ORNL) and at the 3M Company, and testing at the Westinghouse Science and Technology Center (STC) are presented. Demonstration tests at the Tidd PFBC are in progress. Issues identified during the testing and demonstration phases of the development are discussed. Resolution of the issues identified during testing and the status of commercialization of the filters are described.

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The LAJ Cycle: A New Combined-Cycle Fossil Fuel Power System

Volume 2: Turbo Expo 2002, Parts A and B ◽

10.1115/gt2002-30612 ◽

2002 ◽

Author(s):

Roddie R. Judkins ◽

Timothy R. Armstrong ◽

Solomon D. Labinov

Keyword(s):

Fuel Cells ◽

Natural Gas ◽

Power System ◽

Fossil Fuel ◽

High Efficiency ◽

National Laboratory ◽

Combined Cycle ◽

Mitigation Strategies ◽

Model Calculations ◽

Oak Ridge

Oak Ridge National Laboratory (ORNL) has developed a novel system for combined-cycle power generation, called the LAJ cycle. This system could serve as a basis for the development of a new generation of high-efficiency combined cycles. In one of several possible configurations of the new combined-cycle fossil fuel power system, natural gas enters the system at 4.0 MPa and about 300 K, is heated and reformed, and is transferred to a turbine at 4.0 MPa and 1200 K. The gas expands in the turbine to 0.6 MPa and 800 K, and then flows successively to heat exchangers and a condenser-separator, after which it is separated into two gas streams, one containing principally CO with some CH4 and water vapor and the other containing pure H2. The CO and H2 flow to separate fuel cells and undergo electrochemical oxidation with the concomitant production of electricity. Separate streams of water and carbon dioxide (CO2) are produced, making this cycle compatible with carbon mitigation strategies based on sequestration. Model calculations indicate combined-cycle efficiencies greater than 70% based on the lower heating value of natural gas. The high efficiencies realized result from a combination of the high-pressure natural gas reformate expansion and the highly efficient CO and H2 fuel cells. Most of the power derives from the fuel cells in the system.

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Development and Commercialization of Hot Gas Filters for Power Generation Applications

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

10.1115/95-gt-329 ◽

1995 ◽

Author(s):

Thomas E. Lippert ◽

Richard A. Newby

Keyword(s):

Power Generation ◽

Field Test ◽

Coal Gasification ◽

Combined Cycle ◽

Department Of Energy ◽

Fluidized Bed Combustion ◽

Operating Characteristics ◽

Hot Gas ◽

And Performance ◽

First And Second Generation

Westinghouse, with the Department of Energy (Morgantown Energy Technology Center), is developing hot gas particulate filters for application in advanced fossil energy power generation, i.e., pressurized fluidized bed combustion (PFBC) and coal gasification combined cycle (GCC). Westinghouse candle filter units are currently being operated in various coal based pilot plant and demonstration facilities (PFBC and GCC) to demonstrate their operating characteristics and performance and to identify potential commercial viability. Oxide and nonoxide filter materials, representing both first and second generation designs, are being tested and evaluated. In-house testing to characterize ash caking behavior is also being conducted in support of the field test programs. This paper summarizes this activity and presents current results of the field test programs.

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Integration of Combustion Turbine Systems Into Pressurized Fluidized Bed Combustion Combined Cycles

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

10.1115/94-gt-333 ◽

1994 ◽

Cited By ~ 1

Author(s):

R. A. Newby ◽

W. F. Domeracki ◽

A. W. McGuigan ◽

R. L. Bannister

Keyword(s):

Fluidized Bed ◽

High Efficiency ◽

Combined Cycle ◽

Inlet Temperature ◽

Fluidized Bed Combustion ◽

Gas Filtration ◽

Hot Gas ◽

Combined Cycles ◽

Hot Gas Filtration ◽

Pressurized Fluidized Bed Combustion

Currently, pressurized fluidized bed combustion (PFBC) combined cycle power plants apply multiple stages of cyclones to clean the combustion products prior to turbine expansion, and rugged, inefficient expanders are required for this dirty-gas duty. The turbine inlet temperature is limited to the fluid bed combustor temperature, about 843°C (1550°F), so the plant thermal efficiency is relatively low. The development of hot gas filtration and coal-gas topping for PFBC combined cycles is the next step in the evolution of PFBC, and will result in the use of modern, high-efficiency combustion turbines in PFBC applications as well as plant thermal efficiencies up to 47% (HHV). Westinghouse is developing integrated combustion turbine systems that interface with PFBC plants and incorporate the functions of hot gas filtration, alkali vapor removal, topping combustion, hot gas piping and control, and turbine compression and expansion. This paper reports on the engineering considerations made by Westinghouse for these integrated combustion turbine systems and summarizes the current development activities and status.

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Research on the Performance of Solar Aided Power Generation System Based on Annular Fresnel Solar Concentrator

Energies ◽

10.3390/en14061579 ◽

2021 ◽

Vol 14 (6) ◽

pp. 1579

Author(s):

Heng Zhang ◽

Na Wang ◽

Kai Liang ◽

Yang Liu ◽

Haiping Chen

Keyword(s):

Power Generation ◽

High Efficiency ◽

Low Cost ◽

Economic Index ◽

Partial Replacement ◽

Solar Concentrator ◽

Small Disturbance ◽

Step Size ◽

Water Matrix ◽

Cost Utilization

A solar-aided power generation (SAPG) system effectively promotes the high efficiency and low cost utilization of solar energy. In this paper, the SAPG system is represented by conventional coal-fired units and an annular Fresnel solar concentrator (AFSC) system. The annular Fresnel solar concentrator system is adopted to generate solar steam to replace the extraction steam of the turbine. According to the steam–water matrix equation and improved Flugel formula, the variable conditions simulation and analysis of the thermo-economic index were proposed by Matlab. Furthermore, in order to obtain the range of small disturbance, the method of partial replacement is used, that is, the extraction steam of the turbine is replaced from 0 to 100% with a step size of 20%. In this work, a SAPG system is proposed and its thermo-economic index and small disturbance scope are analyzed. The results show that the SAPG system is energy-saving, and the application scope of small disturbance is related to the quantity of the extraction steam and evaluation index.

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Octane Index Applicability over the Pressure-Temperature Domain

Energies ◽

10.3390/en14030607 ◽

2021 ◽

Vol 14 (3) ◽

pp. 607

Author(s):

Tommy R. Powell ◽

James P. Szybist ◽

Flavio Dal Forno Chuahy ◽

Scott J. Curran ◽

John Mengwasser ◽

...

Keyword(s):

High Efficiency ◽

National Laboratory ◽

Operating Conditions ◽

Dominant Factor ◽

Compression Ignition ◽

Oak Ridge ◽

Operating Modes ◽

Wide Range ◽

Thermodynamic Conditions ◽

Si Engines

Modern boosted spark-ignition (SI) engines and emerging advanced compression ignition (ACI) engines operate under conditions that deviate substantially from the conditions of conventional autoignition metrics, namely the research and motor octane numbers (RON and MON). The octane index (OI) is an emerging autoignition metric based on RON and MON which was developed to better describe fuel knock resistance over a broader range of engine conditions. Prior research at Oak Ridge National Laboratory (ORNL) identified that OI performs reasonably well under stoichiometric boosted conditions, but inconsistencies exist in the ability of OI to predict autoignition behavior under ACI strategies. Instead, the autoignition behavior under ACI operation was found to correlate more closely to fuel composition, suggesting fuel chemistry differences that are insensitive to the conditions of the RON and MON tests may become the dominant factor under these high efficiency operating conditions. This investigation builds on earlier work to study autoignition behavior over six pressure-temperature (PT) trajectories that correspond to a wide range of operating conditions, including boosted SI operation, partial fuel stratification (PFS), and spark-assisted compression ignition (SACI). A total of 12 different fuels were investigated, including the Co-Optima core fuels and five fuels that represent refinery-relevant blending streams. It was found that, for the ACI operating modes investigated here, the low temperature reactions dominate reactivity, similar to boosted SI operating conditions because their PT trajectories lay close to the RON trajectory. Additionally, the OI metric was found to adequately predict autoignition resistance over the PT domain, for the ACI conditions investigated here, and for fuels from different chemical families. This finding is in contrast with the prior study using a different type of ACI operation with different thermodynamic conditions, specifically a significantly higher temperature at the start of compression, illustrating that fuel response depends highly on the ACI strategy being used.

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Externally-Fired Combined Cycle Repowering of Existing Steam Plants

Volume 3C: General ◽

10.1115/93-gt-359 ◽

1993 ◽

Cited By ~ 4

Author(s):

Christian L. Vandervort ◽

Mohammed R. Bary ◽

Larry E. Stoddard ◽

Steven T. Higgins

Keyword(s):

Heat Exchanger ◽

Steam Turbine ◽

Gas Turbine ◽

High Efficiency ◽

Low Cost ◽

Operating Experience ◽

Capital Cost ◽

Combined Cycle ◽

Plant Design ◽

Generating Capacity

The Externally-Fired Combined Cycle (EFCC) is an attractive emerging technology for powering high efficiency combined gas and steam turbine cycles with coal or other ash bearing fuels. The key near-term market for the EFCC is likely to be repowering of existing coal fueled power generation units. Repowering with an EFCC system offers utilities the ability to improve efficiency of existing plants by 25 to 60 percent, while doubling generating capacity. Repowering can be accomplished at a capital cost half that of a new facility of similar capacity. Furthermore, the EFCC concept does not require complex chemical processes, and is therefore very compatible with existing utility operating experience. In the EFCC, the heat input to the gas turbine is supplied indirectly through a ceramic heat exchanger. The heat exchanger, coupled with an atmospheric coal combustor and auxiliary components, replaces the conventional gas turbine combustor. Addition of a steam bottoming plant and exhaust cleanup system completes the combined cycle. A conceptual design has been developed for EFCC repowering of an existing reference plant which operates with a 48 MW steam turbine at a net plant efficiency of 25 percent. The repowered plant design uses a General Electric LM6000 gas turbine package in the EFCC power island. Topping the existing steam plant with the coal fueled EFCC improves efficiency to nearly 40 percent. The capital cost of this upgrade is 1,090/kW. When combined with the high efficiency, the low cost of coal, and low operation and maintenance costs, the resulting cost of electricity is competitive for base load generation.

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