Low-Emission Gas-Turbine Combustion

This page updated November 18, 2005.

Catalytica Combustion Systems, Inc.

Low-Emission Gas-Turbine Combustion

CARB Grant Number 96-337

The statements and conclusions in this Report are those of the grantee and not necessarily those of the California Air Resources Board. The mention of commercial products, their source, or their use in connection with material reported herein is not to be construed as actual or implied endorsement of such products.

Executive Summary
The concept of catalytic combustion has been recognized as the ultimate solution for NOx control in gas turbines for over 20 years. Many research companies have tried to solve the problems associated with its application. None have succeeded until the technological breakthrough by Catalytica Combustion Systems, Inc. (CCSI) with XONON™ Flameless Combustion.
CCSI has worked on this technology since 1988 and to date has invested over $20 million in development programs and in research and testing facilities. As part of the development programs, CCSI has installed at its Mountain View facility two sophisticated high-pressure subscale combustor test rigs which simulate the conditions present in a gas turbine combustor. With these test rigs, catalytic combustion reactors can be operated at the actual conditions of a gas turbine combustor, including simulation of start-up and shut down. Atmospheric test capability has also been added to the Mountain View facility for XONON combustion system component testing. A XONON Technology overview is found in Appendix A.
CCSI has developed the basic technology, the specialized materials and the fabrication procedures that are part of this XONON technology. The technology has been demonstrated in CCSI's high pressure test facilities at conditions typical of modern gas turbine engines. Test results show that XONON technology can achieve emission levels of <3 ppm NOx with CO and UHC levels <10 ppm. In addition, CCSI has developed technology needed to interface the XONON catalyst module with the gas turbine including the structural support and container for the catalyst and required fuel injection technology.
CCSI has programs with the major turbine manufacturers including GE, Solar Turbines, and Rolls Royce Allison to apply catalytic combustion technology to new gas turbines. In CCSI's joint program with General Electric, full scale tests have been performed at turbine operating conditions in the laboratory in a single catalytic combustor. The single can is one of 10 cans of the GE MS9001EA series gas turbine, a 105 MW gas turbine used for electric power generation with a combustor discharge temperature of 1250°C (2,280°F). The tests demonstrated for this particular catalytic reactor design ultra low emissions and the potential for turbine grade durability. Emissions of less than 3 ppmv NOx were achieved at baseload conditions. The basic design approach was the starting point for the XONON 2 program addressed in this report. The XONON 2 program picks up where the earlier programs left off and takes the technology to commercial field demonstration and availability to the power generation and mechanical drive markets.
The XONON 2 combustion system includes the combustor with catalyst module, control system, and fuel delivery system. The combustor design and development was accomplished by CCSI. The first catalytic combustion system (XONON 1) design was done by the Agilis Group in West Palm Beach, Florida under CCSI's direction. The XONON 1 work was not a part of the ICAT program. Initial design for the XONON 2 system was also done by the Agilis Group, but the finalization of the preburner and mixing systems was done by CCSI engineers based on testing and Computational Fluid Dynamics (CFD) analysis. The Woodward Governor Company designed and developed the controls and fuel delivery system with assistance from CCSI. Both companies performed component development testing on system hardware in preparation for the engine demonstration.
The first gas turbine testing with a catalytic combustion system (XONON 1) was done on a Kawasaki M1A-13A gas turbine. The gas turbine was installed in a production test cell at AGC in Tulsa, Oklahoma and operated with a water brake dynamometer. Several modifications were made to the initial design based on information gathered during testing at typical industrial operating conditions. Various control strategies were tested to provide the required fuel scheduling for acceleration to full speed at no load (FSNL) while limiting catalyst and metal temperature rise rates and temperature distribution. Fuel strategies were also tested to accelerate the system from FSNL to full power in response to demand. This work was successfully completed with the measurement of full load NOx levels of less than 3 ppm. Before completion of testing at AGC, a 1,000-hour endurance test was run to gain experience with catalyst durability and gas turbine operation over extended periods.
XONON 1 testing at Tulsa showed that a gas turbine could operate successfully with catalytic combustion. It is also showed that the NOx emission targets of less than 3 ppm could be reached. One feature of commercial operation that was not measurable was the reaction to the demands of the electrical grid. The plan was to move testing to another site at which operation against the grid was possible.
A Kawasaki M1A-13A gas turbine generator set was purchased by CCSI for continued combustion system testing. The generator set was for demonstration at the CCSI test facility in Santa Clara, California, where the generator could be connected to the utility grid. Prior to testing, the system was shaken down with the XONON 1 catalytic combustor used in testing at Tulsa and subjected to source testing for the air quality permit. Permitting was accomplished and testing began on the XONON 2 combustor.
Testing at the Santa Clara test facility was planned to demonstrate the combustor's ability to automatically connect to the utility grid, operate continuously on the grid, to react to sudden load sheds and to operate at the target emission levels. During this time, the controls were also tuned to provide the stability necessary to handle the demands of the grid. The conclusions drawn from demonstration are that the system (1) is capable of operating continuously while connected to the utility grid, (2) can be reliably and repeatedly started and auto synchronized with the grid (3) and can be operated and controlled in a manner to meet the emission requirements.
The ICAT program funding covered the design of the XONON 2 combustion system components and assemblies for rig test as well as the engine-ready hardware demonstrated on the gas turbine. It also covered the design and construction of the test facilities at Mountain View and Santa Clara and the installation of the Kawasaki generator set, system shakedown, as well as the field demonstration of the XONON 2 combustion system operating against the utility grid. The results discussed in this report are for the entire combustion system program through field demonstration at the Santa Clara Test Facility.

Funding Source

Funding Amount


$   324,250



 Click here for the entire final report.

ICAT Funded Projects