European IGCC: Achieving high-hydrogen gas combustion at low NOx

The European H2-IGCC project's goal is to enable combustion of undiluted hydrogen-rich syngas with low NOX emissions and also  allowing for high fuel flexibility. The challenge is to operate a stable  and controllable gas turbine on hydrogen-rich  syngas with emissions and processes similar to current state-of-the-art natural gas turbine engines. The first year achievements of this four-year project have been announced.

ETN is the Coordinator of the H

2

-IGCC Project, which is co-funded by the European Commission, Directorate-General for Energy, under the European Union's Seventh Framework Programme (FP7) for Research and Technological Development.

The H2-IGCC project aims to tackle low NOx combustion of high-hydrogen gas by enabling the burning of back-up fuels, such as natural gas, without adversely affecting the reliability and availability. The project will be successful when it  results in the identification and development of gas turbine technology able to operate on undiluted H2-rich fuel gas (approx. 80 Vol. % of hydrogen) from a CO2 capture process in an IGCC plant configuration which offers less than 5%  efficiency penalty (compared to a non-CCS scheme).

The H2-IGCC project brings together 24  partners from industry and academia  with the common goal to increase gas turbine efficiency and fuel flexibility without affecting the reliability and availability in a pre-combustion IGCCCCS plant configuration.

The technical challenges addressed by the H2-IGCC project are divided into 4  Subprojects (SP).

The H2-IGCC project is in its first phase of research and development, and its second phase of proof of principle (labscale) has recently started. In the first year the SPs aligned their research efforts and initiated the following activities:

 Design of a prototype scaled burner;

 Generating kinetic validation data;

 Manufacturing and coating the testing samples;

 Construction of generic geometries for a compressor, cooling system and turbine;

 Decision on plant specification and detailed thermodynamic performance analysis of the selected IGCC cycles.

SP1 – COMBUSTION

Subproject Objective: demonstrate the use of (undiluted) high hydrogen syngas in typical natural gas combustion systems with minimal modifications in order to conserve the ability to burn a variety of fuels; demonstrate the safe use of (undiluted) high hydrogen syngas in lean premixed combustion mode at competitive low emission levels.

First year results:

 Performed  experimental  studies to measure the ignition delay times that showed that the ignition delays of hydrogen decreases with increasing temperature and pressure (in the low temperature range).

 Designed a heat flux burner for elevated pressures to measure laminar flame speeds.

 Tested several kinetic mechanisms to investigate their applicability for NOX prediction and hydrogen combustion.

 Defined experimental techniques to be used in the investigations of the lean premix combustor design for hydrogen-rich syngas.

 Initiated a series of full scale burner prototype CFD calculation and  prepared preliminary designs for various syngas prototype burners for a 280 MW rated heavy duty industrial gas turbine.

 Initiated the preparations design and manufacturing of combustors) for testing innovative combustion techniques, for instance flameless oxidation and catalytically supported “wet” combustion.

SP2 – MATERIALS

Subproject Objective: demonstrate cost-effective materials and coatings technologies to overcome the component life-limiting problems of overheating and of hot corrosion resulting from the higher temperatures and from residual contaminants in the syngas respectively; validate materials performance data, life prediction and monitoring methods  applicable to the industrial implementation in advanced IGCC plants.

First Year Results:

 Detailing of the three gas turbine component operating conditions in process.

 Gas turbine materials, both base alloys and coatings, have been identified,  purchased and machined into samples, ready for the application of the state of the art coatings.

 Validated the coating application process by performing test on dummy test pieces using various sample geometries.

 Detailed planning of the non-destructive examination (NDE).

 Performed initial NDE trials on a combustor.

SP 3 – TURBOMACHINERY

Subproject Objective: deliver a compressor design with a stability margin enabling the switch between fuels without compromising its efficiency; deliver a turbine design and cooling system capable of coping with the resulting heat transfer environment dominated by water vapour; verify designs using large scale virtual testing environment to meet  industrial standards.

First Year Results:

 Performed a literature survey to compose a list with gas turbines in the 250-300 MW class currently on the market, to serve as a basis to select a reference machine.

 Used a generic compressor model and engine as a reference for thermodynamic analysis.

 Designed the baseline geometry of the compressor.

 Completed the generic geometry for the turbine and the cooling passages of the turbines.

SP 4 – SYSTEM ANALYSIS

Subproject Objective: provide a detailed system solution/system analysis that generates realistic techno-economical results for future gas turbine based IGCC plants.

First Year Results:

 A literature survey was performed to collect both technical and performance data of existing IGCC plants. Also, an inventory of features of existing available machines and apparatuses suitable to be used in advanced ICGG plants was made.

 Defined a reference plant layout as well as relevant data for a plant simulation.

 Performed a survey of existing simulation component models available at partners’ facilities.

 System modeling and subsystem integration work  in progress through close collaboration between all SPs.

 On-going development of the Gas Turbine simulator: developed and tested the models for the gas turbine inlet section and compressor; other components are foreseen to be added.

 Preliminary plant specification for reference configuration was specified and fuel flexibility was clarified.