A thermal burn, the firing temperature is higher than normal, coal burner stretched as far as possible to the kiln, the flame should be a long, slow turn to the kiln. Cool slightly higher firing temperature when burned, coal burner finally retreated as far as possible, and the flame can not be long, kiln speed to strive forward. 2, burning circle should be protected good "kiln skin." 3, the mobile PCI tube position, note the line-shaped flame can not sweep "kiln skin." 4, the front end laps, or kilns circle (also known as the coal circle) knot in the firing zone and cooling zone at the junction, due to wind coal with the bad, or the coarse coal particle size, ash and moisture, causing black attempting long kiln firing zone to move molten material condenses in the kiln mouth so that the "kiln skin" thickening, not in time, will develop into a circle. Or because the coal falls on clinker, clinker formation in reducing combustion, as ferrous iron reduction, the formation of low melting point of the mineral or due to high content of ash Ai1O3 increased liquid leaving the clinker, clinker melt material increases, when faced with the secondary air into the kiln is cooled, it will gradually condensed ring formed at the mouth of the kiln. When the ring is not very high, enabling the calcining kiln, the material in the firing zone can extend the residence time of the material compound more complete and reduces the content of free CaO. But the circle is not too high. The above article by Henan YuFeng Heavy Machinery finishing post!