Peculiarities of rotating furnace operation when using diffusive combustion of natural gas

Abstract

One of the features of the organization of the thermal operation of rotary furnaces is the use of a heat load distributed along its length, the value of which is provided by the design of the burner device. On an industrial scale, studies were carried out on the thermal operation of a rotary kiln for calcining limestone with a length of 75 m and a diameter of 3.5 m using a single-wire GRV type on a two-wire GRF-35 in diffusion modes. Long-term industrial tests of the roasting complex have shown the possibilities:

 ‒ increase of air blast heating temperature from 504 to 582 оС with increase of thermal efficiency of lime cooler from 89.89 to 91.3 %;

 ‒ reduction of the degree of preliminary roasting and limestone in the shaft heater from 29.33 to 18.31 % with a decrease in the temperature of heating limestone from 230 to 158 °C and the temperature of the exhaust gases from it from 369 to 297 °C and an increase in its thermal efficiency from 46.75 to 51.52 %;

 ‒ increasing the length of the high-temperature part of the flare from 16 to 50 m;

 ‒ increasing the thermal efficiency of the rotary kiln from 55.37 to 59.08 %, the final degree of calcination of limestone from 90.51 to 98.97 % and the depth of endothermic limestone decomposition processes from 41.78 to 44.38 %;

 ‒ reduction of specific consumption of natural gas from 191.54 to 121.86 m3/t specific consumption of heat from 2244.76 to 1446.04 kW/t of lime. Ill. 1. Ref. 9. Tab. 4.