When the front circle reaches a certain height, it will not only affect the fire watching, but also reduce the ventilation area, which will affect the complete combustion of pulverized coal, and make the large pieces and materials piled up behind the circle, which will damage the kiln skin and lining materials. Due to the high ring height, material regulations, the fire is generally very bright. If the material is slightly thick, it will feel sticky and loose, and it can not be normally controlled, and then add the ring height. The wind speed is high. It is easy to cause waste from large and slow trains and reduce production and quality.

The formation of this kind of ring is generally caused by the flame over working, the firing zone moving backward, the clinker slowly cooling or the coal settling, and the material out of the firing zone contains more liquid phase. Since the length of the front ring is at the junction of the firing zone and the cooling zone, it can be directly burned with the flame, so changing the flame position can solve the problem.

There are two ways to deal with the front ring: slow burning and rapid burning. Slow firing is to burn off the ring in a long time, which is suitable for the treatment of the front ring with wide thickness and high height and the bad kiln skin in the ring. Quick burning is to burn off the ring in a short time. This method is suitable for the front ring which is long and close to the inside. The method of slow firing is similar to that of fast firing, but the length of firing time and the size of closing air are different.

When the front ring is burned rapidly, the exhaust air is generally smaller, and the tail temperature drops more, even at the kiln speed fluctuation. When the front ring is slowly fired, the exhaust air is larger, which has no effect on the normal calcination. When the coal pipe is pulled back and the flame position is shortened or changed, the exhaust air size is used to control.