Work starting method for removing blanking side wall effect of dry quenching furnace

Abstract

The invention relates to the technical field of dry quenching, in particular to a start-up method for removing the blanking side wall effect of a dry quenching furnace, which specifically comprises the following steps of: before normal-temperature start-up, comprehensively checking the inner wall of each area of the dry quenching furnace according to the sequence of a pre-storage section, a chute area and a cooling section, and flattening the unsmooth part of the inner wall, which protrudes more than 10mm; after leveling treatment, refractory mortar is used for spraying treatment on the pre-storage section, the chute area and the cooling section area; strictly controlling the oven temperature and the oven pressure when entering the oven stage; after the coke dry quenching furnace is dried, a coke charging dry quenching production early stage is started, and a control mode of closing peripheral air flues in the furnace for centralized air supply is adopted to operate in a coke discharging mode with the maximum coke discharging flow speed; and when the maximum temperature difference of the four temperature measuring points at the T3 temperature of the lower circumference of the cooling section of the dry quenching furnace is less than or equal to 125 DEG C and the maximum temperature difference of the four temperature measuring points at the T4 temperature of the upper circumference of the cooling section of the dry quenching furnace is less than or equal to 155 DEG C, the blanking of the dry quenching coke is uniform and the side wall effect is eliminated.

Description

Technical Field

[0001] The present invention relates to the technical field of coke dry quenching, and particularly to a start-up method for removing the side wall effect of the charging of a coke dry quenching furnace. Background Art

[0002] The coke dry quenching technology and equipment is a low-carbon emission reduction technology vigorously promoted by the state in the field of pretreatment of iron and steel metallurgy raw materials. Compared with the traditional wet coke quenching, coke dry quenching has unique advantages in energy conservation, environmental protection, significantly improving the quality of coke, and improving the variety structure. In the process, inert gas is used as the circulating gas to exchange heat with the hot red coke in the coke dry quenching furnace to quench the red coke. The coke dry quenching furnace is the core equipment for cooling the red coke, typically a vertical trough with a circular cross-section. The hot coke passes through the pre-storage chamber, the inclined channel area, and the cooling chamber from top to bottom in sequence, and is discharged after being cooled.

[0003] After the newly built coke dry quenching furnace is put into production, due to the construction structure characteristics of the coke dry quenching furnace, there is a problem that the charging speed of coke in the middle of the coke dry quenching furnace is fast, and the charging speed near the inner wall periphery of the coke dry quenching furnace is slow, which is called the side wall effect of the coke dry quenching furnace. The side wall effect may cause the coke to stay in the inclined channel for a long time. Seriously, the coke may be blown into the inclined channel, resulting in the occurrence of floating coke phenomenon. Furthermore, the passage of the inclined channel outlet of the coke dry quenching will be reduced, the resistance will gradually increase, the circulating air volume will decrease, resulting in an increase in the temperature at the boiler inlet and the coke discharging temperature, affecting the rapid reaching of production capacity and the normal production operation of the coke dry quenching.

[0004] The Chinese utility model patent with the publication number of CN 214299982 U discloses a system for improving the coke dry quenching processing capacity. This system helps to improve the operating performance of the coke dry quenching, but does not directly address the solution effect of the side wall effect of the coke dry quenching furnace during the start-up period, that is, no obvious improvement has been achieved. Summary of the Invention

[0005] To overcome the defects of the prior art, the technical problem solved by the present invention is to provide a start-up method for removing the side wall effect of the charging of a coke dry quenching furnace. The present invention adopts the method of inner wall leveling treatment + spraying refractory mud, which can solve the problem of the side wall effect of the charging of the coke dry quenching furnace.

[0006] To achieve the above object, the present invention is realized by adopting the following technical solutions:

[0007] A start-up method for removing the side wall effect of the charging of a coke dry quenching furnace, and the specific method is as follows:

[0008] (1) Before starting at normal temperature, comprehensively inspect the inner walls of each area of the coke dry quenching furnace in the order of the pre-storage section, the inclined channel area, and the cooling section, and level the uneven parts on the inner wall that protrude more than 10 mm.

[0009] (2) After the leveling treatment, the pre-storage section, the inclined channel area and the cooling section area are sprayed with refractory mortar; among them, the refractory mortar used in the pre-storage section and the cooling section area contains 25-35% of aluminosilicate components; the refractory mortar used in the inclined channel area contains 35-45% of aluminosilicate components;

[0010] (3) When entering the oven drying stage, strictly control the oven drying temperature and the oven drying pressure; the temperature of the oven drying is 750-850 °C; during the oven drying process, the oven drying pressure ≥ 15 Pa;

[0011] (4) After the oven drying of the coke dry quenching furnace is completed, at the beginning of the pre-production stage of coke charging and dry quenching, adopt the centralized air supply control method by closing the peripheral air ducts in the furnace and operate in the maximum coke discharging flow rate mode. Wait until the maximum temperature difference of the 4 temperature measurement points of the T3 temperature at the lower circumference of the cooling section of the coke dry quenching furnace ≤ 125 °C, and the maximum temperature difference of the 4 temperature measurement points of the T4 temperature at the upper circumference of the cooling section of the coke dry quenching furnace ≤ 155 °C, which indicates that the coke discharging of the dry quenched coke has reached uniformity and the side wall effect has been eliminated.

[0012] The spraying thickness of the refractory mortar is controlled within 0.5-3 mm.

[0013] The spraying method of the refractory mortar is machine spraying or manual spraying.

[0014] After the refractory mortar is sprayed, it needs to be left standing for at least 24 h.

[0015] The temperature rise during the oven drying stage is heated at 1±0.3 °C / h between room temperature and 130 °C; and heated at 3.5±0.5 °C / h between 130 °C and 800 °C.

[0016] To reach the oven drying temperature, it needs to be kept warm for 1-2 h.

[0017] The aluminosilicate components in the refractory mortar used in the pre-storage section and the cooling section area are in the form of alumina and silica, among which the mass percentage of the alumina component is not less than 25%, and the mass percentage of the silica component is not less than 9%; the aluminosilicate components in the refractory mortar used in the inclined channel area are in the form of alumina and silica, among which the mass percentage of the alumina component is not less than 29%, and the mass percentage of the silica component is not less than 9%.

[0018] Compared with the prior art, the beneficial effects of the present invention are:

[0019] By successively carrying out leveling treatment, spraying operation, strictly controlling the oven drying temperature and the oven drying pressure, and adopting the centralized air supply control method by closing the peripheral air ducts in the furnace to carry out the maximum coke discharging flow rate on the inner walls of the pre-storage section, the inclined channel area and the cooling section of the coke dry quenching furnace, the present invention can effectively solve the problem of the side wall effect of the coke discharging during the start-up period of the dry quenching furnace and shorten the time for the coke dry quenching furnace to reach full production.

[0020] The refractory mortar used in the pre-storage section and the cooling section of the present invention contains 25-35% of aluminosilicate components, which improves the sealing effect; the refractory mortar used in the inclined flue area contains 35-45% of aluminosilicate components, which improves the wear resistance and resists the erosion of materials. Specific Embodiments

[0021] The following further describes the specific embodiments of the present invention:

[0022] The present invention provides a start-up method for removing the side wall effect of the charging of the coke dry quenching furnace, which can be applied before the start-up of a newly built coke dry quenching furnace or before the start-up after the major overhaul of the coke dry quenching furnace.

[0023] This embodiment is applied after the major overhaul of a 140 t / h coke dry quenching plant, and the specific method is as follows:

[0024] (1) After the major overhaul of the 140 t / h coke dry quenching plant and before the start-up at normal temperature, the inner walls of each area of the coke dry quenching furnace are comprehensively inspected in the order of the pre-storage section, the inclined flue area, and the cooling section, and the uneven parts protruding more than 10 mm on the inner wall are leveled.

[0025] (2) After the leveling treatment, the pre-storage section, the inclined flue area, and the cooling section are sprayed with refractory mortar by manual spraying. Among them, the refractory mortar used in the pre-storage section and the cooling section contains 30% of aluminosilicate components; the aluminosilicate components are in the form of alumina and silica, among which the mass percentage of the single component of alumina is 26%, and the mass percentage of the single component of silica is 9%. The refractory mortar used in the inclined flue area contains 40% of aluminosilicate components. The aluminosilicate components are in the form of alumina and silica, among which the mass percentage of the single component of alumina is 30%, and the mass percentage of the single component of silica is 10%. The spraying thickness of the refractory mortar is controlled at 1.5 mm. After the spraying of the refractory mortar, it is left standing for 24 h.

[0026] (3) When entering the stove drying stage, the stove drying temperature and the stove drying pressure are strictly controlled; the stove drying temperature is 800 °C and it needs to be kept warm for 1 h. During the stove drying process, the stove drying pressure is 20 Pa to ensure that the water vapor generated during the stove drying process is normally discharged outside the furnace, and to avoid the influence on the furnace ventilation and the coke dry quenching charging caused by the condensation of water vapor and the caking of coke powder. The temperature rise during the stove drying stage is increased at a rate of 1 ± 0.3 °C / h between room temperature and 130 °C; and at a rate of 3.5 ± 0.5 °C / h between 130 °C and 800 °C.

[0027] (4) After the oven drying of the coke dry quenching furnace is completed and before the start of coke charging and dry quenching production, the centralized air supply control method of closing the peripheral air ducts in the furnace is adopted to operate in the coke discharging mode with the maximum coke discharging flow rate (the designed value of coke discharging amount per unit time). When the maximum temperature difference among the 4 temperature measurement points of the T3 temperature on the lower circumference of the cooling section of the coke dry quenching furnace is 120 °C and the maximum temperature difference among the 4 temperature measurement points of the T4 temperature on the upper circumference of the cooling section of the coke dry quenching furnace is 155 °C, it indicates that the coke discharging has reached uniformity and the side wall effect has been eliminated. Subsequently, the coke discharging temperature and the coke discharging mode can be adjusted according to production. It takes 13 days from starting production at normal temperature to reaching full production after the side wall effect is eliminated, saving 48 hours compared with 15 days before the application of the technology, and the efficiency increase reaches 13.3%.

[0028] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solutions of the present invention, and these simple modifications all fall within the protection scope of the present invention. In addition, it should be noted that, among the various specific technical features described in the above specific embodiments, they can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the present invention will not separately describe various possible combination methods. In addition, any combination can be made among various different embodiments of the present invention, as long as it does not violate the idea of the present invention, it should also be regarded as the content disclosed by the present invention.

Claims

1. A start-up method for removing the sidewall effect of the charging of a coke dry quenching furnace, characterized in that, The specific method is as follows: (1) Before starting operation at normal temperature, comprehensively inspect the inner walls of each area of the coke dry quenching furnace in the order of the storage section, the inclined flue area, and the cooling section, and level the uneven parts on the inner wall that protrude more than 10 mm; (2) After leveling, spray refractory mortar on the storage section, the inclined flue area, and the cooling section; among them, the refractory mortar used in the storage section and the cooling section contains 25-35% of aluminosilicate components; the refractory mortar used in the inclined flue area contains 35-45% of aluminosilicate components; (3) When entering the oven drying stage, strictly control the oven drying temperature and the oven drying pressure; the temperature of the oven drying is 750-850 °C; the oven drying pressure ≥ 15 Pa during the oven drying process; (4) After the oven drying of the coke dry quenching furnace is completed and before the start of coke charging and dry quenching production, adopt the centralized air supply control method by closing the peripheral air ducts in the furnace and operate in the maximum coke discharging flow rate coke discharging mode. When the maximum temperature difference of the 4 temperature measurement points of the T3 temperature at the lower circumference of the cooling section of the coke dry quenching furnace ≤ 125 °C and the maximum temperature difference of the 4 temperature measurement points of the T4 temperature at the upper circumference of the cooling section of the coke dry quenching furnace ≤ 155 °C, it indicates that the coke discharging of the dry quenched coke has reached uniformity and the side wall effect has been eliminated.

2. The start-up method for removing the sidewall effect of the charging of the coke dry quenching furnace according to claim 1, characterized in that, The spraying thickness of the refractory mortar is controlled within 0.5-3 mm.

3. The start-up method for removing the side wall effect of the dry quenching furnace charging according to claim 1, characterized in that, The spraying method of the refractory mortar is machine spraying or manual spraying.

4. A start-up method for removing the side-wall effect of the charging of a coke dry quenching furnace according to claim 1, characterized in that, After the refractory mortar is sprayed, it needs to be left standing for at least 24 h.

5. The start-up method for removing the side wall effect of the charging in the coke dry quenching furnace according to claim 1, characterized in that, The temperature rise during the oven drying stage is heated at 1±0.3 °C / h between room temperature and 130 °C; and heated at 3.5±0.5 °C / h between 130 °C and 800 °C.

6. The start-up method for removing the side wall effect of the charging of the coke dry quenching furnace according to claim 1, characterized in that, When reaching the oven drying temperature, it needs to be kept warm for 1-2 h.

7. A starting method for removing the side wall effect of coke discharging in a dry quenching furnace according to claim 1, characterized in that The form of the aluminosilicate components in the refractory mortar used in the storage section and the cooling section is alumina and silica, where the mass percentage of the alumina component is not less than 25%, and the mass percentage of the silica component is not less than 9%; the form of the aluminosilicate components in the refractory mortar used in the inclined flue area is alumina and silica, where the mass percentage of the alumina component is not less than 29%, and the mass percentage of the silica component is not less than 9%.