Method and device for cleaning the blast furnace top gas downcomer

Abstract

The application discloses a kind of blast furnace top gas downcomer cleaning method and device, method includes the following steps: during blast furnace blowing-off, open the diffuser valve of blast furnace top and the valve on gravity dust collector, dry gas is passed into gas downcomer;Clean through hole is opened on communication pipe, communication pipe is communicated with gas downcomer;Close the valve on gravity dust collector, and stop dry gas into gas downcomer, and cleaning nozzle sprays high-pressure gas to the inner wall of gas downcomer and carries out blowing operation;Stop blowing operation, open the valve on gravity dust collector, and the adherent blown off from the inner wall of gas downcomer falls into gravity dust collector.In blowing operation before starting, the valve on gravity dust collector is closed, can avoid the adherent blown off by gravity dust collector and enter the bag system of blast furnace, when the valve on gravity dust collector is opened, the adherent accumulated in gas downcomer can fall into the bottom of gravity dust collector under the action of pressure and gravity.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of blast furnace ironmaking, and in particular to a blast furnace top gas downcomer cleaning method and device. BACKGROUND

[0002] The blast furnace top gas downcomer is a gas passage during normal production of the blast furnace. The gas downcomer guides the gas generated at the top of the blast furnace to a gas bag system. The lower end of the gas downcomer is connected to a gravity dust collector, and dust, particulate matter and the like contained in the gas fall into the gravity dust collector under the action of gravity, and the dust and particulate matter inside the gravity dust collector are periodically discharged.

[0003] At present, the service life of the blast furnace is the same as that of the gas downcomer, that is, the blast furnace is operated for several years, and the gas downcomer is operated for several years simultaneously. With the extension of the production cycle of the blast furnace, because the top gas contains a large amount of dust, the protective Zn (zinc) and a large amount of alkali metal materials in the dust, and the gas often contains a large amount of water vapor, it is impossible to avoid the existence of adhesives inside the downcomer. With the increase of the adhesives, the gravity of the downcomer is greatly increased, especially for the blast furnace with a production life of more than 10 years, because the adhesives on the inner wall of the downcomer continuously increase, the overall gravity of the downcomer is increased, the huge tensile stress causes the deformation of the structure of the top of the blast furnace, and the valve of the gravity dust collector of the blast furnace cannot be tightly closed, and the top valve cannot be tightly closed, etc.

[0004] When the adhesives in the downcomer are too much, the gas inside the pipeline is usually replaced clean under the condition of blast furnace blowing down, air is introduced, a respirator is worn to enter the inside of the pipeline, and tools are used to clean the adhesives manually. The operation is particularly labor-intensive, and the dust flying during the cleaning of the adhesives is harmful to the operators. SUMMARY

[0005] The purpose of the embodiment of the present application is to provide a blast furnace top gas downcomer cleaning method and device which can safely and effectively clean the adhesives in the downcomer.

[0006] In order to achieve the above purpose, the present application adopts the following technical scheme:

[0007] In a first aspect, a blast furnace top gas downcomer cleaning method is provided, comprising the following steps:

[0008] Step 100, during the blowing down of the blast furnace, opening the diffuser valve at the top of the blast furnace and the valve on the gravity dust collector, and introducing dry gas into the gas downcomer;

[0009] Step 200, a cleaning through hole is formed on the communication pipe connecting the diffuser valve and the gas downcomer;

[0010] Step 300: Close the valve on the gravity dust collector and stop the flow of the dry gas into the gas downcomer. Then, extend the cleaning nozzle of the cleaning device into the gas downcomer through the cleaning through hole. The cleaning nozzle sprays high-pressure gas onto the inner wall of the gas downcomer for purging.

[0011] Step 400: Stop the purging operation, open the valve on the gravity dust collector, and the adhesive material blown off the inner wall of the gas downcomer falls into the gravity dust collector.

[0012] As a preferred embodiment of the method for cleaning the gas downcomer at the top of a blast furnace, before inserting the cleaning nozzle into the cleaning through-hole, the method further includes:

[0013] The gas concentration in the gas downcomer is detected. When the gas concentration in the gas downcomer is higher than or equal to a first preset value, the valve on the gravity dust collector is opened. When the gas concentration in the gas downcomer is lower than the first preset value, the valve on the gravity dust collector is closed.

[0014] As a preferred method for cleaning the gas downcomer at the top of a blast furnace, the thickness of the adhesive material inside the downcomer is first detected. When the thickness of the adhesive material is greater than a second preset value, the gas concentration inside the downcomer is then detected.

[0015] As a preferred embodiment of the method for cleaning the gas downcomer at the top of a blast furnace, during the purging operation, the cleaning nozzle gradually moves upward from the bottom of the gas downcomer.

[0016] As a preferred embodiment of the method for cleaning the gas downcomer pipe at the top of a blast furnace, the distance between the cleaning nozzle and the cleaning through hole is L, and the pressure of the high-pressure gas is P. When L is less than or equal to a third preset value, P gradually decreases with L, and when L = 0, P = 0.

[0017] As a preferred embodiment of the method for cleaning the gas downcomer pipe at the top of the blast furnace, the cleaning through hole is located in the connection area between the connecting pipe and the gas downcomer pipe, and the opening of the cleaning through hole faces upward.

[0018] As a preferred embodiment of the method for cleaning the gas downcomer pipe at the top of the blast furnace, step 200 specifically involves opening the cleaning through hole after the gas in the downcomer pipe has been vented and the temperature of the connecting pipe is lower than a fourth preset value.

[0019] As a preferred method for cleaning the gas downcomer pipe at the top of the blast furnace, steps 300 and 400 are repeated until the adhesive material inside the gas downcomer pipe is completely removed.

[0020] As a preferred embodiment of the method for cleaning the gas downcomer at the top of a blast furnace, during the purging operation, the cleaning nozzle taps the inner wall of the gas downcomer.

[0021] Secondly, a blast furnace top gas downcomer cleaning device is provided, applied to the above-mentioned blast furnace top gas downcomer cleaning method, including a cleaning nozzle and a high-pressure pump. The cleaning nozzle includes a first pipe body and a second pipe body. The first pipe body is a rigid pipe, and the second pipe body is a flexible pipe. The second pipe body is connected to the high-pressure pump, which is used to deliver high-pressure gas to the cleaning nozzle. At least two sets of jet hole groups are provided on the side of the first pipe body. All the jet hole groups are spaced apart along the length direction of the first pipe body. Each jet hole group includes multiple jet through holes, which are arranged in a ring around the central axis of the first pipe body. The jet through holes on adjacent sets of jet hole groups are staggered.

[0022] The beneficial effects of this invention are as follows: By introducing dry gas into the gas downcomer, the adhesive material inside the downcomer can be dried, thereby reducing the stickiness of the adhesive material and facilitating subsequent purging operations; by setting cleaning through holes, the insertion of cleaning nozzles can be facilitated; since high-pressure gas needs to be introduced into the gas downcomer during purging, closing the valve on the gravity dust collector before the purging operation begins can prevent the blown-off adhesive material from entering the bag filter system of the blast furnace through the gravity dust collector. At the same time, it can also reduce the inflow of high-pressure gas into the gravity dust collector, so that a pressure difference can be formed between the gravity dust collector and the gas downcomer. When the valve on the gravity dust collector is opened, the adhesive material accumulated in the gas downcomer can fall to the bottom of the gravity dust collector under the combined action of pressure and gravity, reducing the probability of the adhesive material entering the bag filter system and preventing the adhesive material from scattering everywhere. Attached Figure Description

[0023] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0024] Fig. 1 This is a schematic diagram of the blast furnace described in an embodiment of the present invention.

[0025] Fig. 2 This is a schematic diagram showing the connection of the gas downcomer, gravity dust collector, and bag filter system according to an embodiment of the present invention.

[0026] Fig. 3 This is a schematic diagram of the first tube body in an embodiment of the present invention.

[0027] In the picture:

[0028] 100. Blast furnace;

[0029] 1. Gas downcomer; 2. Connecting pipe; 3. Vent valve; 4. Gravity dust collector; 5. Valve; 6. Bag filter system; 7. First pipe body; 71. Jet nozzle group; 711. Jet through-hole; 8. Cleaning through-hole. Detailed Implementation

[0030] To make the technical problems solved by the present invention, the technical solutions adopted, and the technical effects achieved clearer, the technical solutions of the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0032] like Figs. 1 to 3 As shown, the present invention provides a method for cleaning the gas downcomer at the top of a blast furnace, comprising the following steps:

[0033] Step 100: During the shutdown of blast furnace 100, open the vent valve 3 on the top of blast furnace 100 and the valve 5 on the gravity dust collector 4 to introduce dry gas into the gas downcomer 1.

[0034] Step 200: Open a cleaning through hole 8 on the connecting pipe 2 that connects the vent valve 3 and the gas downcomer 1;

[0035] Step 300: Close valve 5 on gravity dust collector 4 and stop supplying dry gas into gas downcomer 1. Then, insert the cleaning nozzle of the cleaning device into gas downcomer 1 through cleaning through hole 8 and spray high-pressure gas onto the inner wall of gas downcomer 1 for purging.

[0036] Step 400: Stop the purging operation and open valve 5 on gravity dust collector 4. The adhesive material blown off the inner wall of the gas downcomer 1 falls into gravity dust collector 4.

[0037] By introducing dry gas into the gas downcomer 1, the adhering material inside the downcomer 1 can be dried, thereby reducing the stickiness of the adhering material and facilitating subsequent purging operations. The cleaning through-hole 8 facilitates the insertion of the cleaning nozzle. Since high-pressure gas needs to be introduced into the gas downcomer 1 during purging, closing the valve 5 on the gravity dust collector 4 before the purging operation begins can prevent the blown-off adhering material from entering the bag filter system 6 of the blast furnace 100 through the gravity dust collector 4. At the same time, it can also reduce the inflow of high-pressure gas into the gravity dust collector 4, so that a pressure difference can be formed between the gravity dust collector 4 and the gas downcomer 1. When the valve 5 on the gravity dust collector 4 is opened, the adhering material accumulated in the gas downcomer 1 can fall to the bottom of the gravity dust collector 4 under the combined action of pressure and gravity, reducing the probability of the adhering material entering the bag filter system 6 and preventing the adhering material from scattering everywhere.

[0038] In this embodiment, both the gravity dust collector 4 and the valve 5 on the gravity dust collector 4 are existing technologies. The valve 5 on the gravity dust collector 4 is not a completely sealed structure. The valve 5 is a plate-shaped structure. The upper end of the gravity dust collector 4 is a conical tube. The plate-shaped valve 5 is set inside the conical tube. The shape of the valve 5 is consistent with the cross-sectional shape of the conical tube, which can be circular or square. By moving the position of the valve 5 up and down, the distance between the periphery of the valve 5 and the inner wall of the conical tube can be adjusted. When the valve 5 moves up to abut against the inner wall of the conical tube, the valve 5 is in a closed state. However, there is still a gap between the valve 5 and the inner wall of the conical tube. Some gas can flow into the gravity dust collector 4 through this gap (and the pressure in the gas downcomer 1 is relatively large. The pressure difference can further push the gas to flow into the gravity dust collector 4, preventing the gas from flowing out of the cleaning through hole 8 in the opposite direction). The size of the adhesive is large and cannot enter the gravity dust collector 4 through this gap.

[0039] The baghouse system 6 refers to the baghouse dust collector for the blast furnace. This baghouse dust collector is an existing piece of equipment. The blast furnace baghouse dust collector is a new type of high-efficiency baghouse dust collector improved upon the experience of various non-standard baghouse dust collectors used in blast furnace gas purification in China. It can also be used in dust removal and purification systems for other positive-pressure operating flammable and explosive gases. The baghouse dust collector has a welded integral structure, integrating the housing, inlet and outlet ducts, ash hopper, and vent pipe. This integral design ensures good airtightness, prevents leaks, and guarantees safety and reliability, thus protecting the atmospheric environment and the personal safety of personnel. All equipment undergoes rigorous pressure and airtightness tests before leaving the factory and is equipped with explosion-proof valves and vent pipes. After preliminary separation (coarse purification), the blast furnace gas enters the housing through the lower inlet. Larger dust particles fall naturally into the ash hopper due to gravity, while smaller particles disperse in the gaps between the filter bags in the filter chamber and are trapped on the surface of the filter bags. The filtered clean gas is then delivered to users through the pipeline network. As the filtration process continues, more dust adheres to the surface of the bag filter, gradually increasing the filter bag resistance. When the filter bag resistance reaches its upper limit, the system automatically opens the clean gas backflushing valve, sending clean gas into the static pressure box to backflush the filter bags. This causes the filter bags to expand from a collapsed state, shaking off the dust adsorbed on the outer surface of the filter bags into the ash hopper at the bottom of the box. The dust in the ash hopper is then discharged through the ash discharge valve. When the filter bag resistance reaches its lower limit, the control system automatically closes the clean gas backflushing valve, stopping the backflushing cleaning, and the dust collector resumes its purification and filtration operation.

[0040] Furthermore, before inserting the cleaning nozzle into the cleaning through-hole 8, the method further includes: detecting the gas concentration in the gas downcomer 1; opening the valve 5 on the gravity dust collector 4 when the gas concentration in the gas downcomer 1 is higher than or equal to a first preset value; and closing the valve 5 on the gravity dust collector 4 when the gas concentration in the gas downcomer 1 is lower than the first preset value. By detecting the gas concentration in the gas downcomer 1, the safety of the purging operation under the current conditions can be determined. In this embodiment, the gravity dust collector 4 is connected to the gas downcomer 1 and is connected to the outside. When the gas concentration in the gas downcomer 1 is higher than or equal to the first preset value, opening the valve 5 on the gravity dust collector 4 allows for internal gas exchange between the gravity dust collector 4 and the gas downcomer 1, reducing the gas concentration in the gas downcomer 1 and thus improving the safety of the purging operation. In this embodiment, the first preset value is 30 ppm.

[0041] Furthermore, the thickness of the adhesive material inside the gas downcomer 1 is first detected. When the thickness of the adhesive material exceeds a second preset value, the gas concentration inside the gas downcomer 1 is then detected. By setting the system to first detect the thickness of the adhesive material inside the gas downcomer 1, and then detect the gas concentration when the thickness exceeds the second preset value, it is possible to determine whether purging is necessary based on the thickness of the adhesive material. If the adhesive material is small, it can be cleaned after a period of time, thus reducing the workload. The second preset value is 10mm. The thickness of the adhesive material inside the gas downcomer 1 can be detected as either the overall thickness of the adhesive material or the thickness of a specific area of ​​the adhesive material.

[0042] Furthermore, during the purging operation, the cleaning nozzle gradually moves upward from the bottom of the gas downpipe 1. In this embodiment, the cleaning nozzle is first extended to the bottom of the gas downpipe 1, and then the purging operation is performed. During the purging operation, the cleaning nozzle is continuously pulled upward so that it can reach various parts of the inner wall of the gas downpipe 1. It is understood that the blown-off adhesive material will accumulate at the bottom of the gas downpipe 1 under the action of gravity. By setting the cleaning nozzle to gradually move upward from the bottom of the gas downpipe 1 during the purging operation, it is possible to prevent the cleaning nozzle from blowing up the blown-off adhesive material again, reduce the impact of the blown-off adhesive material on the high-pressure gas flow path, and thus enable the high-pressure gas to continuously blow off the adhesive material attached to the inner wall of the gas downpipe 1.

[0043] In this embodiment, the distance between the cleaning nozzle and the cleaning through-hole 8 is L, and the pressure of the high-pressure gas is P. When L is less than or equal to a third preset value, P gradually decreases with L, and when L = 0, P = 0. That is, when the cleaning nozzle is near the cleaning through-hole 8, the pressure of the high-pressure gas is reduced. When the cleaning nozzle moves to the cleaning through-hole 8, the high-pressure gas is shut off. This reduces the splashing of adhesive material at the cleaning through-hole 8, allowing the adhesive material to fall and accumulate at the bottom of the gas downcomer 1. After the valve 5 on the gravity dust collector 4 is opened, the material falls into the gravity dust collector 4 for centralized treatment. In this embodiment, the third preset value is 500 mm. In this embodiment, the moving speed of the cleaning nozzle during purging is 1 meter / minute. When L is greater than the third preset value, the pressure of the high-pressure gas is greater than 1.0 MPa.

[0044] Furthermore, the cleaning through-hole 8 is located in the connection area between the connecting pipe 2 and the gas downcomer 1, and the opening of the cleaning through-hole 8 faces upward. In this embodiment, there are two connecting pipes 2, forming a T-junction between the gas downcomer 1 and the two connecting pipes 2. The cleaning through-hole 8 is located in the forked area of ​​the T-junction, which facilitates the insertion of the cleaning nozzle into the interior of the gas downcomer 1. By setting the opening of the cleaning through-hole 8 to face upward, on the one hand, it can prevent the adhesive material in the vicinity of the cleaning through-hole 8 from splashing out from the cleaning through-hole 8, and on the other hand, it can reduce the difficulty of the purging operation. In this embodiment, the cleaning through-hole 8 is a square hole, which facilitates the opening of the cleaning through-hole 8. For example, the side length of the cleaning through-hole 8 is 200mm.

[0045] Further, step 200 specifically involves opening the cleaning through hole 8 only after the gas in the gas downcomer 1 has been emptied and the temperature of the connecting pipe 2 is below a fourth preset value. In this embodiment, both the gas downcomer 1 and the connecting pipe 2 are metal pipes. When cutting the pipes to open the cleaning through hole 8, sparks are inevitable. Setting the cleaning through hole 8 to be opened only after the gas in the gas downcomer 1 has been emptied and the temperature of the connecting pipe 2 is below the fourth preset value can improve the safety of the operation and prevent explosions. Opening the cleaning through hole 8 only after the temperature of the connecting pipe 2 is below the fourth preset value can reduce the probability of workers being burned during the operation. For example, the fourth preset value is 50°C. In this embodiment, since the end of the gas downcomer 1 is connected to the gravity dust collector 4, the gas content in the gas downcomer 1 can be preliminarily determined by detecting the gas concentration in the gravity dust collector 4, thereby controlling the opening time of the cleaning through hole 8. If the gas concentration detected in the gravity dust collector 4 is too high, then dry gas should continue to be introduced until the gas concentration reaches a safe value, so as to avoid an explosion when opening the cleaning through hole 8 and improve the safety of the operation.

[0046] In one embodiment, there is a lot of adhesive residue inside the gas downpipe 1, which is difficult to clean completely in one purging. Therefore, steps 300 and 400 need to be repeated until the adhesive residue inside the gas downpipe 1 is completely removed.

[0047] Furthermore, after cleaning is completed, the cleaning nozzle is removed, and the cleaning through hole 8 is sealed with a cover plate cast with refractory mortar. Then, the gap between the cover plate and the wall of the cleaning through hole 8 is filled with refractory mortar, and the outside is welded and sealed.

[0048] In this embodiment, the drying gas is nitrogen. It is understood that nitrogen is the most abundant gas in the air, and using nitrogen as the drying gas can reduce operational costs. In this embodiment, the high-pressure gas is high-pressure air.

[0049] In this embodiment, during the purging operation, the cleaning nozzle taps the inner wall of the gas downpipe 1. By setting the cleaning nozzle to tap the inner wall of the gas downpipe 1, it is beneficial to peel off the adhesive from the inner wall of the gas downpipe 1, thereby improving the cleaning effect.

[0050] This embodiment also provides a blast furnace top gas downcomer cleaning device, applied to the blast furnace top gas downcomer cleaning method in any of the above embodiments. It includes a cleaning nozzle and a high-pressure pump. The cleaning nozzle includes a first pipe body 7 and a second pipe body. The first pipe body 7 is a rigid pipe, and the second pipe body is a flexible pipe. The second pipe body is connected to the high-pressure pump, which is used to deliver high-pressure gas to the cleaning nozzle. At least two sets of jet hole groups 71 are provided on the side of the first pipe body 7. All jet hole groups 71 are spaced apart along the length direction of the first pipe body 7. The jet hole group 71 includes multiple jet through holes 711. The multiple jet through holes 711 are arranged in a ring around the central axis of the first pipe body 7. The jet through holes 711 on adjacent sets of jet hole groups 71 are staggered. By setting the first tube 7 as a rigid tube, the cleaning nozzle can be easily inserted into the bottom of the gas downpipe 1; by setting the second tube as a flexible tube, when the high-pressure gas ejected from the jet through hole 711 blows towards the inner wall of the gas downpipe 1, a recoil force will be generated. The recoil force can lift the first tube 7, thereby driving the first tube 7 and the second tube to make irregular movements, thus improving the purging effect.

[0051] In this embodiment, the first tube 7 is a steel pipe with a wall thickness of 2mm, and the second tube is a rubber tube. The first tube 7 and the second tube are sealed together. The first tube 7 is a blind end away from the second tube, meaning that the end of the first tube 7 away from the second tube is sealed. The length of the first tube 7 is 200mm, and the outer diameter is 30-50mm. A first set of air jet holes 71 is provided at a distance of 180mm from the second tube on the first tube 7. The first set of air jet holes 71 includes four air jet through holes 711, which are evenly arranged around the central axis of the first tube 7. A second set of air jet holes 711 is provided at a distance of 120mm from the second tube on the first tube 7. The first group of air vents 71 includes a second group of air vents 711, comprising four air vents 711 evenly arranged around the central axis of the first pipe body 7. The air vents 711 of the second group are staggered from those of the first group. A third group of air vents 71 is located 60mm from the second pipe body on the first pipe body 7. This third group also comprises four air vents 711 evenly arranged around the central axis of the first pipe body 7, and the air vents 711 of the third group are aligned with those of the first group. In this embodiment, the diameter of the air vents 711 is 1-2mm. The diameter of the air vents 711 in each group of air vents 71 can be the same or different. The length of the second pipe body can be adjusted according to the length of the gas downcomer 1.

[0052] The complete workflow of this embodiment is as follows:

[0053] The first step is to fabricate the cleaning nozzle. Weld and seal one end of a 200mm long steel pipe with an outer diameter of 30-50mm. The pipe wall thickness is 2mm. Drill four holes at a 90-degree angle around the outer wall of the steel pipe at a point 180mm long. These holes are the first group. Drill a second group of holes at a point 120mm long, offset from the first group at a 45-degree angle (the first group is in the southeast, northeast, southwest, and northwest directions, the second group is in the southeast, northeast, southwest, and northwest directions), with a diameter of 1-2mm. Drill a third group of holes at a point 60mm long, perpendicular to the first group, with a diameter of 1-2mm. All holes should be of the same size; the higher the compressed air pressure, the larger the hole diameter. Connect the perforated steel pipe to the rubber hose according to the total length of the gas downcomer pipe 1, ensuring a tight seal to prevent air leakage.

[0054] The second step involves cleaning the deposits on the gas downcomer 1. During the blast furnace shutdown (100°C), no steam is introduced into the furnace top; only nitrogen is introduced (to prevent the deposits from becoming damp and reducing the purging effect). After the shutdown, the furnace top vent valve 3 is fully opened, the furnace top manhole is opened, and the gravity dust collector 4 is opened to depressurize and cool the furnace top. After the gas replacement inside the gas downcomer 1 is complete, and the temperature at the furnace top connecting pipe 2 is below 50°C, a square hole with a side length of 200mm is opened at the intersection of the two connecting pipes 2, i.e., a cleaning through hole 8 (the square hole facilitates subsequent sealing). The thickness of the deposits on the inner wall of the gas downcomer 1 is checked through the square hole. When the deposit thickness exceeds 10mm, or when a localized deposit thickness exceeding 10mm is detected, the deposits are cleaned.

[0055] If the thickness of the adhesive is greater than 10mm, the gas concentration inside the gas downcomer 1 needs to be checked. If the gas concentration is greater than 30ppm, open valve 5 of gravity dust collector 4 to allow the pressurized nitrogen inside gravity dust collector 4 to enter the gas downcomer 1 for purging and replacement until the gas content inside the gas downcomer 1 is less than 30ppm. Then close valve 5 of gravity dust collector 4.

[0056] The purging process is as follows: Connect the prepared rubber hose to the pre-drilled steel pipe purging head. Based on the total length of the gas downpipe 1, insert the rubber hose and steel pipe (i.e., the cleaning nozzle) into the gas downpipe 1 until they reach the bottom. Introduce high-pressure compressed air to the opening and connect it to the rubber hose; the compressed air pressure should be greater than 1.0 MPa. The high-pressure compressed air is blown out from the jet nozzle 711 on the steel pipe. The compressed air generates a huge recoil force against the inner wall of the gas downpipe 1, causing the steel pipe to bounce up and the rubber hose to move randomly. The high-pressure compressed air blown out from the jet nozzle 711 purifies the deposits adhering to the inner wall of the gas downpipe 1. During the purging process, continuously raise the rubber hose, controlling the raising speed at 1 meter per minute. When the rubber hose is raised to 500 mm from the cleaning nozzle 8, slowly reduce the compressed air pressure and flow rate until it reaches the cleaning nozzle 8, then shut off the compressed air. After the purging stops, open valve 5 of gravity dust collector 4 to allow the cleaned adhesive to fall to the bottom of gravity dust collector 4. At the same time, pressurized nitrogen gas introduced into gravity dust collector 4 enters gas downcomer 1 to purge the adhesive loosened by the first purging.

[0057] Before the second purging, close valve 5 of the gravity dust collector and follow the same steps as the first cleaning. Repeat this process several times (e.g., 3 times) until the internal ash is basically cleaned. If the blast furnace has not undergone cleaning of adhering materials for over 100 years, multiple cleaning cycles can be performed.

[0058] Normally, cleaning is carried out annually during wind closures, and repeating the cleaning operation three times a year is sufficient to completely remove the adhesive residue.

[0059] After the cleaning process is completed, a cover plate of the same area is cast using refractory mortar. The cover plate is then installed at the cleaning through hole 8, and the gaps are filled with refractory mortar. The exterior is then welded and sealed. The cleaning operation is now complete.

[0060] In the description herein, it should be understood that the terms "upper," "lower," "left," "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings, and are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. Furthermore, the terms "first" and "second" are used merely for descriptive distinction and have no special meaning.

[0061] In the description of this specification, references to terms such as "an embodiment," "example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example.

[0062] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style of the specification is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

[0063] The technical principles of the present invention have been described above with reference to specific embodiments. These descriptions are merely for explaining the principles of the invention and should not be construed as limiting the scope of protection of the invention in any way. Based on this explanation, those skilled in the art can readily conceive of other specific embodiments of the invention without inventive effort, and these embodiments will all fall within the scope of protection of the present invention.

Claims

1. A method of cleaning a blast furnace top gas downcomer, characterized in that, The method comprises the following steps: Step 100, during the blast furnace blowing down, opening the diffuser valve of the blast furnace top and the valve on the gravity dust collector, and introducing dry gas into the gas downcomer; Step 200, opening a cleaning through hole on the communication pipe connecting the diffuser valve and the gas downcomer; Step 300, closing the valve on the gravity dust collector, stopping the introduction of dry gas into the gas downcomer, and then extending the cleaning nozzle of the cleaning device into the gas downcomer through the cleaning through hole, and the cleaning nozzle sprays high-pressure gas to the inner wall of the gas downcomer for blowing operation; Step 400, stopping the blowing operation, opening the valve on the gravity dust collector, and the adhering material blown off from the inner wall of the gas downcomer falls into the gravity dust collector; During the blowing operation, the cleaning nozzle gradually moves upward from the bottom of the gas downcomer; The distance between the cleaning nozzle and the cleaning through hole is L, and the pressure of the high-pressure gas is P, when L is less than or equal to the third preset value, P gradually decreases with the decrease of L, and when L=0, P=0.

2. The blast furnace top gas downcomer cleaning method according to claim 1, characterized in that, Before extending the cleaning nozzle into the cleaning through hole, further comprising: Detecting the concentration of gas in the gas downcomer, when the concentration of gas in the gas downcomer is higher than or equal to the first preset value, opening the valve on the gravity dust collector, and when the concentration of gas in the gas downcomer is lower than the first preset value, closing the valve on the gravity dust collector.

3. The blast furnace top gas downcomer cleaning method according to claim 2, characterized in that, First detecting the thickness of the adhering material in the gas downcomer, and then detecting the concentration of gas in the gas downcomer when the thickness of the adhering material is greater than the second preset value.

4. The blast furnace top gas downcomer cleaning method according to any one of claims 1 to 3, characterized in that, The cleaning through hole is arranged in the connection area between the communication pipe and the gas downcomer, and the opening of the cleaning through hole is arranged upward.

5. The blast furnace top gas downcomer cleaning method according to any one of claims 1 to 3, characterized in that, The step 200 specifically comprises: opening the cleaning through hole when the gas in the gas downcomer is exhausted and the temperature of the communication pipe is lower than the fourth preset value.

6. A blast furnace top gas downcomer cleaning method according to any one of claims 1 to 3, characterized in that, Repeating the step 300 and the step 400 until the adhering material in the gas downcomer is completely removed.

7. A blast furnace top gas downcomer cleaning method according to any one of claims 1 to 3, characterized in that, During the blowing operation, the cleaning nozzle knocks the inner wall of the gas downcomer.

8. A blast furnace top gas downcomer cleaning device characterized by, The application is applied to the blast furnace top gas downcomer cleaning method in any one of claims 1-7, comprising a cleaning nozzle and a high-pressure pump, the cleaning nozzle comprises a first pipe body and a second pipe body, the first pipe body is a hard pipe, the second pipe body is a flexible pipe, the second pipe body is connected to the high-pressure pump, the high-pressure pump is used for conveying high-pressure gas to the cleaning nozzle, at least two groups of jet hole groups are arranged on the side surface of the first pipe body, all the jet hole groups are arranged at intervals along the length direction of the first pipe body, the jet hole group comprises a plurality of jet through holes, the plurality of jet through holes are annularly arranged around the central axis of the first pipe body, and the jet through holes on adjacent two groups of jet hole groups are arranged in a staggered manner.

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