Countermeasures for Blast Furnace Tuyere Burning Loss

According to the analysis of the damage form of blast furnace tuyere, formulate a targeted blast furnace operation management system, and technical measures to prevent tuyere burning and leakage, improve the service life of the tuyere, reduce the air break rate, improve economic benefits, and achieve safe and efficient blast furnace production. Mainly focus on the following work:
(1)Concentrate technology to improve and stabilize the quality of raw materials and reduce harmful elements entering the furnace. Strengthen the screening of raw fuels, and conduct screening, monitoring and assessment of the whole process of charging into the furnace.
(2)Control technology for harmful elements. Study the influence of harmful element enrichment on tuyere deformation, track the changes of harmful elements, establish a harmful element early warning system and a regular alkali discharge system; study the influence mechanism of harmful elements on tuyere deformation, study the control range of harmful elements, and study how to reduce harmful elements through blast furnace operation. Elemental hazards to blast furnaces. Track changes in harmful elements, and establish an early warning system for harmful elements and a regular alkali discharge system. The blast furnace zinc load is lower than 300g/t-p, and the alkali load is lower than 4kg/t-p, which can effectively reduce the influence of harmful elements on the wind deformation caused by enrichment.
Control the amount of alkali metal entering the furnace, and adopt the method of appropriately reducing the basicity of the slag to discharge alkali. The range of sulfur content in molten iron can be relaxed, from the current 0.01-0.02% to 0.03-0.45%. However, this operation requires that the components (especially the sintering basicity) of the ore entering the furnace must be relatively stable.
(3)Improve the stability of blast furnace conditions.
Change the idea of the fabric, and resolutely control the edge airflow. Develop central airflow, control edge airflow, and improve gas utilization. This is an important fabric method to reduce costs and run smoothly.
Reasonably adjust the lower system and thermal system according to the peripheral changes, control the reasonable furnace type parameters, and make reasonable corrections to the blast furnace control parameters and furnace type parameters through production practice to further promote the improvement of the forward running degree of the furnace conditions. Some furnace parameters are revised again, and the thermal system is adjusted according to the change of the titanium load into the furnace, especially the control of furnace temperature and alkalinity. Such a virtuous circle achieves long-term stability.
(4)Improve the material of the spray gun, install and adjust the position and angle of the spray gun correctly. The stable oxygen-enriched coal injection operation maintains a reasonable theoretical combustion temperature before the tuyere according to the level of the coal injection ratio.
(5)Blast furnace tapping management. Determine a reasonable taphole angle and depth, determine a reasonable number of taps, flow rate of molten iron, and time to see slag, so as to reduce the abnormal erosion of the hearth by the slag-iron circulation. According to 1.2~1.5 times of the thickness of the brick lining in the taphole area, determine the taphole depth, iron tapping speed, and slag-iron time ratio of about 0.8. Erosion of tuyere.
(6)In the initial stage of hearth accumulation, treatment is carried out by means of operation, and a hearth pretreatment system is established to improve the activity of the hearth. By means of hearth temperature detection, the trend of local accumulation or activity decline in the hearth can be judged in advance, and the hearth pretreatment system can be established by operating means to deal with it in the initial stage of accumulation in the hearth. Do not use furnace cleaners at the end of the furnace service.
(7)Water quality management. According to water quality test, timely add medicine to kill algae, reduce Ca2+, Mg2+, Cl-1 ions in water, control pH to 7.0, prevent scaling of cooling equipment and reduce cooling effect. After the tuyere leaks, stop the air in time for treatment.
(8)Stable air temperature operation. According to the specific conditions of each hot blast stove, the average air temperature value after conversion should be adopted to use the mixed air control. Instead of simply closing the air mixing valve mechanically. Avoid the change of the temperature field in the furnace caused by the large fluctuation of the air temperature before and after the furnace change.
(9)The tuyere of the same tuyere area that continuously burns and damages the small sleeve shall be operated correspondingly to block the tuyere, and at the same time, check the working condition of the cooling wall in this position. When the heat of the hearth and the fluidity of the slag and iron around the tuyere are good, the tuyere should be opened at the right time to avoid continuous burning and frequent wind break, which will cause a vicious circle.

Post time: Sep-05-2022