Blast furnace coal injection system capable of preventing material blockage

Abstract

The utility model discloses a blast furnace coal injection system capable of preventing material blockage, which comprises an injection tank, a filter and a coal injection distributor, wherein the discharge port end of the coal injection distributor is connected with a coal injection gun through each branch coal injection duct; the injection tank is connected with the filter through a first pipeline, and the filter is connected with the coal injection distributor through a second pipeline; a first three-way valve is arranged on the second pipeline, one end of the first three-way valve is connected with a blowback pipeline, and the blowback pipeline is connected with an air source; a second three-way valve is arranged on the first pipeline, and one end of the second three-way valve is connected with a collecting bag through a collecting pipeline. The utility model has the characteristics of automatic cleaning, low possibility of blockage, safety and reliability.

Description

Technical Field

[0001] The utility model relates to the technical field of blast furnace coal injection, in particular to a blast furnace coal injection system capable of preventing material blockage. Background Art

[0002] Blast furnace coal injection (BFI) is a new technology widely adopted in modern blast furnace ironmaking and an essential tool for regulating furnace conditions. During the blast furnace smelting process, injecting pulverized coal into the blast furnace reduces coke usage, thereby alleviating pollution caused by coking. In actual production, impurities in pulverized coal can sometimes cause blockage in the pulverized coal injection system. Once blocked, the pipes and filters must be cleaned. Existing cleaning methods rely primarily on manual cleaning, which presents the following problems: First, the pipeline must be depressurized before cleaning, and then the filter must be manually opened to manually clean any debris clogged on the filter screen. This cleaning operation is complex, time-consuming, and labor-intensive. Furthermore, this cleaning method only cleans the filter screen, leaving debris in the pipes unremoved. Second, most filters use flat screens, which not only have a small pulverized coal filtration area, but also directly impact the filter screen, where debris easily clogs the mesh. Frequent cleaning is required, and if not done promptly, this can affect the pulverized coal injection process and even damage the equipment. Utility Model Content

[0003] The purpose of the present invention is to provide a blast furnace coal injection system that can prevent material blockage in order to solve the problems mentioned in the background art.

[0004] The problem described in this utility model is solved by the following technical solutions:

[0005] A blast furnace coal injection system capable of preventing material blockage comprises a blowing tank, a filter, and a coal injection distributor, wherein a discharge port end of the coal injection distributor is connected to a coal injection gun via branch coal injection pipes; the blowing tank and the filter are connected via a first pipe, and the filter and the coal injection distributor are connected via a second pipe; a first three-way valve is provided on the second pipe, one end of the first three-way valve is connected to a back-blowing pipe, and the back-blowing pipe is connected to an air source; a second three-way valve is provided on the first pipe, one end of the second three-way valve is connected to a collection bag via a collection pipe.

[0006] The above-mentioned blast furnace coal injection system that can prevent material blockage, the filter consists of a shell and a filter screen; the shell is a three-section structure, the middle section is a cylindrical structure, and the left and right sides are conical cylindrical structures, and the shell is provided with a feed port and a discharge port; the filter screen is a cylindrical structure, and its two ends are respectively connected to the shell, and the open end of the filter screen is facing the discharge port on the shell, forming a pre-filter cavity between the filter screen and the shell, and a post-filter cavity is formed between the inner cavity of the filter screen and the discharge port of the shell.

[0007] In the blast furnace coal injection system capable of preventing material blockage, the cylindrical structure of the filter screen has a taper, and the radius of the opening direction is larger than the radius of the bottom of the tube.

[0008] In the blast furnace coal injection system capable of preventing material blockage, the filter is provided with two feed ports, which are connected in parallel and then connected to the first pipeline.

[0009] The blast furnace coal injection system capable of preventing material blockage is provided with a pressure sensor and a back-blowing valve on the back-blowing pipeline.

[0010] The blast furnace coal injection system capable of preventing material blockage is provided with a temperature sensor on the second pipe.

[0011] The blast furnace coal injection system capable of preventing material blockage is provided with a collecting valve on the collecting pipe. Beneficial effects

[0012] Compared with the existing technology, the present invention has the following advantages: First, the backflush pipe is connected to the air source through the first three-way valve on the second pipe; and the collection pipe and the collection bag are connected to the first pipe through the second three-way valve. When the filter screen or the pipe is blocked, the air source can be connected for backflush. Compared with first releasing the pressure and then opening the filter for manual cleaning, the operation is simple and the cleaning is fast. The debris in the pipe can be backflushed and cleaned. Second, the filter housing adopts a three-section structure and is matched with a cylindrical filter screen. Under the condition of a certain housing space, the filter screen area is larger than that of a flat filter screen. The coal powder injection does not directly hit the filter screen vertically. When impurities are encountered, they can be disturbed in the annular pre-filter cavity, and the probability of blockage is reduced compared with a flat filter screen. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The present invention will be further described below in conjunction with the accompanying drawings.

[0014] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0015] Figure 2 It is another structural schematic diagram of the utility model.

[0016] The numbers in the figure represent: 1. injection tank, 2. filter, 3. coal injection distributor, 4. first pipeline, 5. second pipeline, 6. first three-way valve, 7. back-blowing pipeline, 8. gas source, 9. second three-way valve, 10. collection bag, 11. collection pipeline, 2-1. shell, 2-2. filter, 5-1. temperature sensor, 7-1. pressure sensor, 7-2. back-blowing valve, 11-1. collection valve. DETAILED DESCRIPTION

[0017] The technical solution of the present utility model is described in further detail below with reference to the accompanying drawings.

[0018] See Figures 1 to 2 The utility model includes a blasting tank 1, a filter 2, and a coal injection distributor 3. The outlet end of the coal injection distributor 3 is connected to the coal injection gun via various branch coal injection pipes. The blasting tank 1 and the filter 2 are connected via a first pipe 4, the filter 2 and the feed end of the coal injection distributor 3 are connected via a second pipe 5, and the outlet end of the coal injection distributor 3 is connected to the coal injection gun via various branch coal injection pipes. A first three-way valve 6 is provided on the second pipe 5, one end of which is connected to a backflush pipe 7, which is connected to an air source 8. A second three-way valve 9 is provided on the first pipe 4, one end of which is connected to a collection bag 10 via a collection pipe 11. The first three-way valve 6 and the second three-way valve 9 can be power valves. Two of the three ports of the first three-way valve 6 are connected to the second pipe 5, and the other port is connected to the backflush pipe 7. The collection bag 10 can be a bag filter. The air source 8 can be high-pressure nitrogen. The outlet end of the coal injection distributor 3 is connected to the coal injection gun through each branch coal injection pipe. This is the existing technology and will not be described in detail.

[0019] In order to solve the problem that the pulverized coal filtering area is small and the pulverized coal is directly sprayed toward the filter screen, the filter 2 can adopt the following design scheme: the filter 2 is composed of a shell 2-1 and a filter screen 2-2; the shell 2-1 is a three-section structure, the middle section is a cylindrical structure, and the left and right sides are conical cylindrical structures, and a feed port and a discharge port are provided on the shell 2-1; the filter screen 2 is a cylindrical structure, and its two ends are respectively connected to the shell 2-1, and the open end of the filter screen 2 is directed toward the discharge port on the shell 2-1, and a pre-filter cavity 2-3 is formed between the filter screen 2 and the shell 2-1, and a post-filter cavity 2-4 is formed between the inner cavity of the filter screen 2 and the discharge port of the shell 2-1. The pre-filter cavity 2-3 formed by this structure is an annular structure. The coal powder is not directly sprayed vertically toward the filter screen. When encountering impurities, it can be disturbed in the annular pre-filter cavity 2-3. Only when there are enough impurities will the filter screen 2 be seriously blocked. In addition, when the space of the shell 2-1 is certain, the area of ​​the filter screen 2 is larger than that of the flat filter screen, and the post-filter cavity 2-4 is also large, which is conducive to the discharge of coal powder.

[0020] The cylindrical structure of filter screen 2 can be designed as follows: it has a tapered shape, with the radius of its opening greater than the radius of its base. This tapered shape facilitates the ejection of pulverized coal from the discharge port of housing 2-1. The bottom of filter screen 2 can be connected to one end of the housing or positioned at a distance from the housing. The bottom can be closed or have mesh.

[0021] In order to facilitate the uniform filtration of pulverized coal from the filter screen 2-2 and ensure that debris can be quickly cleaned during backflushing: two feed ports are provided on the filter 2, such as Figure 2As shown, the two feed ports are connected in parallel and connected to the first pipe 4. During feeding, the pulverized coal can enter the post-filter cavity 2-4 evenly from the filter screen 2-2 in the circumferential direction; at the same time, during backflushing, two feed ports are more conducive to the discharge of debris than one feed port.

[0022] In order to facilitate the control of the back-blowing force, the following solution can be adopted: a pressure sensor 7-1 and a back-blowing valve 7-2 are provided on the back-blowing pipe 7. A collection valve 11-1 can be provided on the collection pipe 11.

[0023] To facilitate monitoring of filter and pipeline blockage, a temperature sensor 5-1 can be installed on the second pipeline 5. Since pulverized coal generates heat due to friction with the pipeline when flowing through the second pipeline 5, the amount of pulverized coal flowing through per unit time will affect the pipeline temperature. When blockage occurs, the pulverized coal flow rate decreases, and the pipeline temperature drops, thereby controlling backflushing. The above backflushing can be controlled by the CPU and control circuit. The signal output of the temperature sensor 5-1 is connected to the signal input terminal of the CPU, and the signal output of the pressure sensor 7-1 can also be connected to the input terminal of the CPU. The signal output of the CPU is connected to control the first three-way valve 6, the second three-way valve 9, the backflush valve 7, and the collection valve 11-1 respectively. All of the above valves use power valves, and the CPU can use the C8051F340 series chip.

Claims

1. A blast furnace coal injection system capable of preventing material blockage, characterized in that: The invention comprises a blowing tank (1), a filter (2), and a coal injection distributor (3), wherein the discharge port end of the coal injection distributor (3) is connected to the coal injection gun through each branch coal injection pipe; the blowing tank (1) and the filter (2) are connected through a first pipe (4), and the filter (2) and the coal injection distributor (3) are connected through a second pipe (5); a first three-way valve (6) is provided on the second pipe (5), one end of the first three-way valve (6) is connected to a back-blowing pipe (7), and the back-blowing pipe (7) is connected to an air source (8); a second three-way valve (9) is provided on the first pipe (4), and one end of the second three-way valve (9) is connected to a collecting bag (10) through a collecting pipe (11).

2. The blast furnace coal injection system capable of preventing material blockage according to claim 1, characterized in that: The filter (2) is composed of a shell (2-1) and a filter screen (2-2); the shell (2-1) is a three-section structure, the middle section is a cylindrical structure, and the left and right sides are conical cylindrical structures. The shell (2-1) is provided with a feed port and a discharge port; the filter screen (2-2) is a cylindrical structure, and its two ends are respectively connected to the shell (2-1), the open end of the filter screen (2-2) faces the discharge port on the shell (2-1), a pre-filter cavity (2-3) is formed between the filter screen (2-2) and the shell (2-1), and a post-filter cavity (2-4) is formed between the inner cavity of the filter screen (2-2) and the discharge port of the shell (2-1).

3. The blast furnace coal injection system capable of preventing material blockage according to claim 2, characterized in that: The cylindrical structure of the filter screen (2-2) has a taper, and the radius of the opening direction is larger than the radius of the bottom of the cylinder.

4. The blast furnace coal injection system capable of preventing material blockage according to claim 1, characterized in that: The filter (2) is provided with two feed ports, which are connected in parallel and then connected to the first pipeline (4).

5. The blast furnace coal injection system capable of preventing material blockage according to claim 1, characterized in that: A pressure sensor (7-1) and a backflush valve (7-2) are provided on the backflush pipe (7).

6. The blast furnace coal injection system capable of preventing material blockage according to claim 1, characterized in that: A temperature sensor (5-1) is provided on the second pipe (5).

7. The blast furnace coal injection system capable of preventing material blockage according to claim 1, characterized in that: A collecting valve (11-1) is provided on the collecting pipe (11).

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