Classification of common flame shapes in burners

Classification of common flame shapes in burners
1、 A lively flame.The flame has a suitable shape, length, and blackening time, which is most beneficial for the quality of clinker forging and coal powder combustion efficiency. It meets the temperature requirements of the firing zone, has low heat consumption, and the entire flame is lively and powerful. This is the flame shape that an operator wants to obtain, and it is also a normal forging flame shape.2、 Long black flame.This type of flame has a longer black flame head, lower combustion efficiency, and lower front temperature rise. The reasons for the formation are as follows:① Poor coal quality, low heat generation, high ash content, coarse coal particles, high humidity, etc;② Burner malfunction, resulting in poor coal powder mixing effect and slow combustion speed;③ Using inappropriate burners, with high external air and low internal air, improper coal to air ratio, and insufficient air volume.When such flame formation occurs, it is necessary to analyze the cause in a timely manner, check whether the coal quality and fineness are appropriate, whether the spiral blades of the three channel burner are damaged, and whether the air volume is sufficient. In addition, improper operation can also easily lead to this type of flame, such as the grate bed speed being too fast, resulting in thin material and low secondary air temperature, and the presence of coal powder circles at the kiln mouth, all of which can cause the black flame head to be too long.3、 Slow flame (long flame).The main reason for the lack of concentration of the flame flame is that the internal wind is too small and the rotation is poor, making it unable to spread; The external wind is too strong, the diffusion inhibition is too strong, and the flame is stretched.However, when encountering high front temperature or burning flow phenomenon in the furnace bricks during the operation process, this type of flame can be adopted, which can effectively alleviate it in a timely manner; In addition, this flame form can also be used before ignition, feeding, or hanging the kiln, and can be changed when normal.4、 Diffusion type flames.The shape of the flame is short and thick, belonging to an abnormal flame shape. The main reasons for its formation are:① The fired kiln skin has a circle and large material balls, which promote the flame to move forward, often causing high front temperature, turbidity in the kiln, uneven incoming materials, large fluctuations in the host current, and an increase in negative pressure at the kiln tail. If not handled in a timely manner, it will cause the kiln lining to burn out or the quality of the clinker to be unqualified, resulting in a decrease in output.② Improper use of multi channel coal injection pipes, with excessive internal air and insufficient external air, as well as excessively high secondary air temperature, can easily damage the kiln lining.③ The swirl angle at the end of the internal air duct is too large, making it difficult to control the external wind and causing severe diffusion.④ The flame hood of the multi duct coal injection pipe is burnt out, and the closed smoke hood burns, causing flame spread.When this flame shape is discovered, it is necessary to check in a timely manner whether there are any loops inside the kiln, the proportion of secondary air, whether the temperature of secondary air is too high, whether the negative pressure at the kiln tail is too small, and whether the inclination angle of the spiral blades is appropriate.5、 Touching the kiln skin flame.This flame is offset upwards, which easily washes out the kiln skin, shortens the service life of refractory bricks, raises the furnace temperature, and the flame shape is very abnormal, which is not conducive to heat transfer and clinker quality. The reasons are as follows:① The position of the burner on the cross-section of the kiln body is incorrect, deviating above the centerline, and it is easy to produce a red kiln at a distance of 6m from the kiln body.② The shock wave generated by excessive outward placement of the nozzle and excessive secondary air can cause the flame to float upwards, mainly due to improper operation of the cooler or severe air leakage from the kiln hood.When this shape of flame is discovered, it is necessary to promptly check whether the position of the burner on the cross-section of the kiln body is correct, whether the cold air volume at the kiln head is too large, and whether the secondary air volume is too large. The cause should be dealt with in a timely manner.