Studies On Technology Optimization Of Swirl Burner With Of A In600MW Unit Boiler

With the increasingly serious environmental problems, low NO_xburners and airstaging measures have been widely applied. However, the addition of OFA resulting inthe burner’s ignitability weakened and the furnace easy to slag-bonding. So it is necessaryto exploit the new low NO_xburners to adapt the coal-fired boiler with OFA.In this paper, we study the flow field characteristics of the central-fuel-rich swirlcoal combustion burner pilot. Through the research of the influence of structuralparameters （length and position of the primary air outlet, the length of the secondary airoutlet, and length of the outer secondary air out let） and operating parameters （OFA rate,both inside and outside the secondary air damper volume ratio） on the central-fuel-richswirl coal combustion burner, we find the optimal structure of pulverized coalcombustion in the furnace, and use this structure in the low NO_x combustion systemtransformation project.In this paper, a three-dimensional particle-dynamics anemometer （PDA） system isused to study gas-particle flow characteristics of central-fuel-rich burner with differentOFA rate and ratios of inner/outer secondary air. The result shows that OFA rate andratios of inner/outer secondary air has a more evident effect on the axial velocity andradial velocity, the particle diameter and volume flux are comparatively large in thecentral region outside the burner nozzle. While the volume flux is low in the region nearthe wall.Through the cold air flow experiments and industrial tests carried in a600MWboiler, the conclusions are as follows: the recirculation zone within the outlet region isstable after the low NO_x combustion system transformation, the boiler could be operatedstably at the load of600MW,450MW and300MW, after central-fuel-rich burners areadopted, the NO_xemission at the load of600MW,450MW and300NW decreases to235mg/m³（O₂=6%）,220mg/m³（O₂=6%）,244mg/m³（O₂=6%）.