Combustion characteristics of a four-wall tangential firing pulverized coal furnace

The furnace core temperature (FCT), wall temperature, and tangential circle diameter in a 1 MW four-wall tangential firing furnace (FWTF(F)) were investigated in detail. The FCT and wall temperature of the primary air section of corner tangential firing furnace (CTF(F)) were also studied for comparison. Results show that compared with CTF that exhibited higher temperature distribution in the center of the furnace wall and lower at the corner where the burners are installed, FWTF is more conducive for gas-powder mixture timely ignition and burnout because of the higher temperature and heat flux in the burner zone. FWTF can efficiently prevent slagging in the burner zone because of the small temperature difference of the primary air section. The wall temperature in FWTFF exhibited uniformity, became an uneven parabola-like distribution, and exhibited uniformity again along the flue gas. The maximum temperature difference in CTFF was 1.48 (anthracite) and 3.65 (bituminous) times of that in FWTFF. The actual tangential circle diameters of anthracite and bituminous in FWTFF were approximately 3 and 7.6 times of imaginary tangential circle diameter, respectively.