Concurrent Measurement Of Temperature And Soot Concentration Of Pulverised Coal Flames: Project Summary

Abstract:

<p>The objectives of this project are: <bl> <li>To develop a prototype optical instrumentation system capable of measuring the distributions and fluctuations of temperature and soot concentration of pulverised coal flames.</li> <li>To evaluate the performance of the system on a 0.5MWth combustion test facility at Innogy plc over a range of combustion conditions.</li> <li>To establish quantitative relationships between the flame temperature and soot concentration measured and the corresponding combustion input data, thermal output and emission levels.</li> </bl></p> <p>As a result of this project, a prototype instrumentation system for the concurrent measurement of flame temperature and soot concentration has been developed. The system operates on the principle of multi-wavelength pyrometry combined with digital imaging and image processing techniques. A monochromatic imaging system is used to visualise the flame field in the furnace. The flame light incipient on the optical sensor installed on the furnace wall is split into separate beams passing through narrow band-pass filters of different wavelengths before reaching the imaging device. The resulting digital images are processed to determine temperature distribution of the flame field. The soot concentration of the flame is represented using a parameter called KL factor, which is derived from the temperature measured. The operability and effectiveness of the system have been evaluated on an industrial-scale combustion test facility operated by Innogy plc.</p> <p>Results obtained have demonstrated that the system is capable of measuring two-dimensional distributions and fluctuations of flame temperature and soot concentration. The accuracy of the system was verified using a tungsten lamp as a standard reference source. The relative error between the measured temperature and the reference temperature was found to be no greater than 1% throughout the measurement range from 1280&deg;C to 1690&deg;C. The resolution of the system was dependent upon the resolution of the camera and its installation on the furnace. The prototype system was applied to investigate the distributions of flame temperature and soot concentration of typical pulverised coals. Quantitative relationships between flame temperature, soot concentration and corresponding plant conditions were identified. Preliminary comparisons between the pulverised coal flames and other fossil fuel flames were also undertaken.</p> This summary provides information on: <bl> <li>Objectives</li> <li>Summary</li> <li>Cost</li> <li>Duration</li> <li>Contractor</li> <li>Collaborator</li> <li>Background</li> <li>Methodology</li> <li>System Description</li> <li>Experimental Evaluation</li> <li>Trials on Innogy's Combustion Test Facility</li> <li>Conclusions</li> </bl>

Author(s):

DTI