The objective of the project is to simultaneously study three combustion technologies - swirling, staging, and flameless oxidation - for applications to Compact Fired Heating Units with the aim to:
- simultaneously lower NOx emissions, and reduce furnace volume and floor area for the specific case of increased combustion air preheating; - promote the rational use of energy by constraining NOx emissions for higher temperatures of combustion air preheating than currently used in CFHU applications where the performance is restricted by emissions standards; and
- build a comprehensive set of experimental data which will serve as a database from which simplified design methodologies for optimally integrating burners in CFHU's can be derived.
The work programme is organised in three main parallel work packages which correspond with the different techniques that are explored. Each work programme contains a detailed experimental investigation and limited theoretical modelling work. At least five different combustion chambers, ranging in load from 30 kW to 500 kW and ranging in applications from thermal oil heaters to adiabatic furnaces are being studied. The temperature of the walls range from 300oC up to 1100oC. The various experimental as well as commercial prototype burners use combustion air that is preheated from 200oC up to 1000oC. Measurements include detailed measurements of in-furnace flue gas composition as well as overall "furnace goodness" parameters such as: specified load (kW/m3), specific surface load (kW/m2), in-furnace energy adsorption, aspect ratio of the combustion chamber, etc. The economic advantages that can be achieved by increasing the specific load of the furnace while simultaneously increasing the combustion air preheat and lowering the NOx emissions in applications such as steel reheating furnaces, glass furnaces and process heaters are tremendous. Preliminary results indicate that, for swirling combustion, high swirl numbers are more resistant to NOx increase due to an increase in air preheat than low swirl numbers. The Flameless Oxidation process achieves by far the lowest NOx emissions, but at the expense of a very low value of specific load.
Expected Achievements and Exploitation
The expected output of this project is a comprehensive comparative study of different combustion technologies for different applications. Because the three work packages operate each in close co-operation with manufacturers of burners and furnaces/heaters, the results of the experimental work will immediately be applied by the manufacturers to steer their production line towards the targets set forward in this project. In addition, a Eurotherm conference will be organised which is targeted towards the furnace and burner manufacturers where the results of the findings of this project will be disclosed by the project partners.
Funding SchemeCSC - Cost-sharing contracts
S19 5RP Sheffield
5600 MB Eindhoven
WV5 8BD Wolverhampton