After a long time of production practice, we have realized that only by using hot air as medium and carrier, can we improve the heat utilization rate and thermal work effect. The following hot-blast stove manufacturers to specifically introduce the following hot-blast stove problems need our attention. At this time, the hot blast stove extinguishing chamber and the bed heat storage of the upper stove are limited. After stopping burning, the temperature of the extinguishing chamber will drop very quickly, which requires us to burn the stove many times. 一、热风炉熄灭室及上部炉床蓄热效果差
1. Poor heat storage effect of quenching chamber and upper hearth of hot blast stove
Basically, the extinguishing chamber temperature rises slowly when the furnace is burned, and the flue temperature will be higher when the extinguishing chamber temperature reaches 1200 C. It can not continue to burn the furnace. Otherwise, if the flue temperature exceeds the standard, it will waste a lot of fuel. At this time, the hot blast stove extinguishing chamber and the bed heat storage of the upper stove are limited. After stopping burning, the temperature of the extinguishing chamber will drop very quickly, which requires us to burn the stove many times.
2. The temperature distribution of the furnace bed is extremely uneven, and the temperature of the conversion zone is too low. The easily damaged conversion zone of the silica brick wall and the silica brick bed in this area refers to the transition zone from the silica brick furnace bed to the high alumina brick furnace bed.
Hot blast stove can only be burned under small load when it is kept warm, and the flue temperature will be out of control when it is burned under large load. Liquefied petroleum gas (LPG) low-load burner has a very small amount of flue gas. Hot flue gas quickly reaches the hearth along the central axis of the hot blast stove from the top extinguisher. It is difficult to cover up the whole hearth, resulting in a higher local temperature in the hearth, while it is difficult to raise the local temperature near the hearth wall. During a long time of heat preservation, the temperature in the transition zone near the hearth wall keeps falling. So that it can be reduced to below 600 C. The temperature range of 570 ~ 600 C is the phase transition temperature range of silicon brick. If the temperature is lower than this temperature, the silicon brick will be damaged. When the blast furnace returns to production for the first time, the temperature of the converting zone near the furnace wall will drop to a lower level. When the gas is normal, the furnace will be burned with heavy load. At this time, the temperature of the conversion zone near the furnace wall will rise sharply from 550 C. This is the most taboo situation of the silica brick bed and the silica brick wall. It is very likely that silica brick will be damaged, which will affect the permeability of hot blast stove hearth or the structural destruction of furnace wall.
3. Excessive fuel consumption and high cost of heat preservation
Because the hot blast stove extinguisher is designed based on the physical and chemical parameters of blast furnace gas, the structure of the extinguisher can not be changed. It is difficult to assign the extinguishing condition to a comparatively ideal state when the LPG thermal insulation furnace is used instead. This is the main reason for the poor heat storage and uneven temperature distribution of hot blast stoves. In order to ensure the basic temperature of hot stove, it is necessary to burn stove frequently and waste fuel. Due to the unsatisfactory extinguishing conditions, it is easy to form incomplete extinguishing, fuel wastage and potential safety hazards.
4. Excessive high temperature in the middle of the hearth due to incomplete extinguishing
Because of the uneven distribution of temperature, the temperature of the central position of the hot blast stove will be higher, the temperature of the furnace wall where the thermometer is located will be lower, and the temperature of the central area is higher than that measured by the thermometer in the quenching chamber. The calorific value of liquefied petroleum gas (LPG) is very high, and it is 35 times higher than blast furnace gas. When incomplete extinguishing occurs, the temperature in the central area of hot blast stove will reach above 1500 C, and the thermometer of extinguishing chamber can not be measured.