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Projects: Projects for Investigator
Reference Number 2003-6-49-1-2
Title Low emissions combuster
Status Completed
Energy Categories Hydrogen and Fuel Cells(Fuel Cells) 100%;
Research Types Applied Research and Development 100%
Science and Technology Fields ENGINEERING AND TECHNOLOGY (General Engineering and Mineral & Mining Engineering) 100%
UKERC Cross Cutting Characterisation Not Cross-cutting 100%
Principal Investigator Professor S (Simone ) Hochgreb
No email address given
University of Cambridge
Award Type 3
Funding Source Carbon Trust
Start Date 01 November 2004
End Date 30 September 2006
Duration 23 months
Total Grant Value £129,037
Industrial Sectors
Region East of England
Investigators Principal Investigator Professor S (Simone ) Hochgreb , Engineering, University of Cambridge (100.000%)
Web Site
Objectives The project objectives are: (a) to investigate a new concept for a low-NOx combustor for use with fuel cell off gases; (b) to generate a technical database for the combined performance of a concept burner using hydrogen-rich fuels; (c) to create physical understanding and design rules through the testing of a concept device that could be applicable to solid oxide fuel cell/gas turbine (SOFC/GT) cycles. The stability and emissions characteristics of the conceptual burner will be investigated asa function of inlet conditions and mixture composition.
Abstract A new power system is currently under development at Rolls-Royce Fuel Cells Systems Ltd (RRFCS) for the Distributed Generation (DG) market. DG plant are in the 1-10 MW range and would be located close to where the power is consumed, reducing electricity transmission costs and inefficiencies. The RRFCS system should achieve 55 efficiency at high power densities with the potential of 70 + in later generations. It will be more efficient than other DG products yet cost competitive. A keycomponent of the system is an off-gas combustor. This burns the diluted, unreacted fuel from the fuel cell stack ( 25 ), which in turn heats the incoming stack air to the required operating temperatures of SOFCs. The objective of this project is to develop the understanding necessary to design off-gas combustors for fuel cells producing negligible emissions. There are two significant challenges to developing low emissions off-gas combustors. First, the fuel and oxidizer are unusual mixtures, both in composition and temperature, for which there is no experimental database. Second, there is no pressure difference between the two streams. This means that innovative solutions are required to produce the high mixing rates necessary for low pollutant emissions. To respond to these challenges, a novel burner design has been proposed. Pre-project work showed that this concept, which is based on automobile monolith technology, is both technically feasible and likely to lead to very low nitrous oxide and carbon monoxide pollutant levels, as well as allowing high fuel efficiency, which results in lower CO2 emissions. The concept is currently being verified both at ambient and high temperature and pressure conditions. In addition to the fuel cell application, the fast mixing burner concept will have applications to combustion systems in general. The investigation of stability and emissions characteristics can also be applied to the combustion of synthetic gases such as effluents from chemical industries, biogas and biomass-derived gases, as well as automotive fuel cell concepts
Publications (none)
Final Report (none)
Added to Database 01/01/07