Summary

This paper reports results of an extensive measurement campaign carried out in a 730 MWth bituminous coal fired utility boiler equipped with internally air-staged low-Nox burners. The main objective of the project was to investigate the combustion be-haviour of two different coals under full load conditions. Middle and a high volatile bituminous coal were used during the campaign.

The measurements were carried out in the near-burner zone and in the burnout zone above the over-fire air injection. Particle velocities and temperatures of particle clouds were measured using newly developed non-intrusive probes applying 2-dimensional Laser Doppler Anemometry for velocities and Quotient Pyrometry for temperatures of particle clouds. Gas composition (O2, CO, CO2, and NO) and temperature were deter-mined with conventional suction probes.

The measurement data were then used to validate predictions of an in-house developed CFD code, AIOLOS, of the Institute of Process Engineering and Power Plant Technology (IVD). Gas composition, temperature and velocity distributions in the boiler were calculated with a discretisation of 2,300,000 grid points. The comparison of measured data and predicted results shows a good agreement.