Bag type dust collector for steel-making converter gas purification

Abstract

The utility model discloses a bag type dust collector for gas purification of a steelmaking converter. The ash bucket is of a double-layer ash bucket structure with an inner ash bucket (4) and an outer ash bucket (3); an ash bucket partition plate (5) is arranged between the inner ash bucket (4) and the outer ash bucket (3); an inlet of the air inlet pipe (1) is formed in the lower part of the middle box body (8) or the side surface of the upper part of the outer ash bucket (3); an inner ash bucket ring beam (6) is arranged in a cavity between the lower part of the filter element (9) in the middle box body (8) and the upper part of the outer ash bucket (3) and the air inlet pipe (1); and a passageway partition plate (7) is arranged in an arch-shaped cavity between the upper part of the inner ash bucket ring beam (6) opposite to the air inlet pipe (1), the outside of a filtering area in the middle box body (8) and a wall plate of the middle box body (8). According to the utility model, not only can the scouring of airflow to the filter bag be reduced, but also coal gas or oxygen-containing flue gas remained in the dust remover can be driven in real time, the contact and mixing probability of the coal gas and oxygen is effectively reduced, the occurrence of burning and explosion accidents is avoided, and the safety of equipment is obviously improved. The device is safe, efficient, energy-saving and economical.

Description

Technical Field

[0001] This utility model belongs to the field of converter gas purification technology, specifically relating to a bag filter for purifying converter gas in steelmaking. Background Technology

[0002] The primary flue gas of steelmaking converter has the characteristics of high flue gas temperature, high CO content, and great value for coal gas and waste heat recovery and utilization. However, the dust concentration in the flue gas is as high as 80~150g / m³. In particular, the alternation of coal gas and oxygen-containing flue gas during the smelting process poses a high safety risk.

[0003] Currently, the two main purification processes used are OG (wet process) and LT (dry process).

[0004] OG wet scrubbing has low purification efficiency, can cause water pollution and corrosion, and has relatively high energy consumption.

[0005] The core of LT dry process technology is the use of a plunger-type electrostatic precipitator to capture and remove particulate matter from flue gas, achieving dry purification and recovery of coal gas. This type of electrostatic precipitator effectively prevents direct contact between coal gas and air, greatly reducing the risk of serious combustion and explosion accidents. However, due to the low and unstable dust removal efficiency of the electrostatic precipitator itself, coupled with the sparks generated by corona discharge during operation, combustion and explosion problems still frequently occur. At best, this causes deformation and twisting of the internal electrode plates and wires, resulting in a significant reduction in dust removal efficiency and a significant increase in outlet particulate matter emissions (above 30 mg / m³), thus greatly reducing the quality of recovered coal gas and preventing the flue gas vent from meeting ultra-low emission requirements. At worst, it can cause equipment combustion or even highly destructive explosions, leading to serious safety accidents.

[0006] Baghouse dust collectors are the mainstream technology for the efficient capture of particulate matter in industrial flue gas and the achievement of ultra-low emissions. To achieve ultra-low emissions and improve gas quality, some research institutions and enterprises in China have carried out research and development on the application of baghouse dust collection technology for converter gas. However, the structure of baghouse dust collectors for converter gas, a key core piece of equipment, is basically the same as that for blast furnace gas. These technologies and equipment have two shortcomings: First, the dust collectors do not have specific preventive measures and structural designs for the alternating occurrence of gas and oxygen-containing flue gas in the converter smelting process. They do not have the function of preventing gas and oxygen from coming into contact and mixing, and cannot effectively avoid explosion accidents in the dust collectors, so the safety hazards and risks are still relatively high. Second, the baghouse dust collectors adopt a bottom-inlet method, where the flue gas flows from bottom to top after entering the dust collector, which is opposite to the direction of dust settling. This results in high filtration resistance and high energy consumption during the operation of the dust collector. Summary of the Invention

[0007] This utility model addresses the shortcomings of existing technologies by providing a bag filter for purifying converter gas in steelmaking. It effectively avoids the problem of excessive emissions from LT electrostatic precipitators and the explosion safety hazards of existing conventional bag filters, achieving safe, stable, reliable, and ultra-low emissions for dry purification of converter gas. It can also efficiently and effectively recover and utilize gas and waste heat, thus saving energy resources.

[0008] The technical solution of this utility model is: a bag filter for purifying converter gas in steelmaking, comprising an inlet pipe, a support frame, an ash hopper, a middle box, filter elements, a tube sheet, a clean air chamber, a manhole, a dust removal device, an explosion venting device, an outlet pipe, and a vent pipe. The middle box is welded to the bottom support frame, and a tube sheet is welded to the top. Removable filter elements are sealed and installed on the holes of the tube sheet. The clean air chamber is welded to the top of the tube sheet. Dust removal devices are installed inside and outside the clean air chamber. An outlet pipe and a vent pipe are installed on the top of the clean air chamber. The ash hopper is a double-layer structure with an inner and outer ash hopper. The middle box is a cylindrical structure. A space is provided between the inner and outer ash hoppers. The ash hopper partition has the air inlet pipe located on the side wall between the inner and outer ash hoppers, at the lower part of the middle housing or the upper side of the outer ash hopper. The inner ash hopper has an opening on its windward side. The ash hopper partition is spatially perpendicular to the air inlet pipe and is installed on the longitudinal section at the center of both sides between the inner and outer ash hoppers. An inner ash hopper ring beam is installed in the cavity between the filter element below the middle housing and the outer ash hopper and the air inlet pipe. The inner ash hopper with the opening on its windward side is welded to the lower part of the inner ash hopper ring beam. A channel partition is installed in the arc-shaped cavity between the inner ash hopper ring beam opposite the air inlet pipe and the outer filtration area of ​​the middle housing and the middle housing wall.

[0009] Furthermore, the ash hopper partition has an upper and lower opening structure, with the installation height extending from the lower part of the inner ash hopper ring beam to the inner ash hopper outlet, and the opening rate is 20%~80%.

[0010] Furthermore, the inner ash hopper has a structure with openings at the top and bottom of the windward side wall, with an opening rate of 10% to 60%.

[0011] Furthermore, the clean air chamber is a cylindrical structure with a sealed end cap.

[0012] Furthermore, the clearance between the inner ash hopper ring beam and the bottom outer wall of the filter element is ≥50mm.

[0013] Furthermore, the clearance between the baffle plate and the outer wall of the nearest filter element is ≥50mm.

[0014] Furthermore, the manhole doors are welded to the lower side of the middle housing and the clean air chamber, respectively; the explosion relief device is installed on the upper side of the middle housing and the top of the clean air chamber.

[0015] Furthermore, the explosion relief device can be a diaphragm type, a counterweight type, or a spring type.

[0016] Furthermore, the dust removal device employs pulse jet cleaning and sonic cleaning methods, with inert gas as the air source for pulse jet cleaning.

[0017] Furthermore, the filter element is made of filter material containing ceramic and metal materials according to the flue gas temperature, and its temperature resistance range is 150℃~500℃. It adopts a circular filter bag or filter cartridge structure.

[0018] The main features of this utility model bag filter are: a double-layer ash hopper structure with an inner and outer ash hopper; an open plate on the windward side of the inner ash hopper; and an open baffle between the inner and outer ash hoppers. After the airflow enters the dust collector through the inlet duct, it passes through the inner and outer double-layer ash hoppers, the open baffle, and the open inner ash hopper, allowing the airflow to enter the filtration area from three paths: the bottom of the outer ash hopper, the bottom of the inner ash hopper, and through the baffle. This reduces "dead zones" and effectively removes residual coal gas, preventing combustion and explosion accidents caused by the mixing of coal gas and oxygen-containing flue gas. It also disperses the airflow, preventing excessive downward-flowing dust-laden air from scouring the filter bags and avoiding premature filter bag failure.

[0019] This invention uses the arc-shaped space opposite the air inlet pipe as an airflow rising channel (clamp) to reduce the rising speed of the airflow at the bottom of the dust collector, avoid the airflow from scouring the filter element and reduce resistance.

[0020] The working principle of this utility model is as follows: The primary flue gas (coal gas) of the converter enters the dust collector through the side air inlet pipe and is divided into three parts by the inner and outer double-layer ash hoppers, the perforated ash hopper baffles and the perforated inner ash hopper. One part flows through the lower channel of the outer ash hopper (the channel between the inner ash hopper discharge port and the outer ash hopper discharge port) and enters the opposite channel to drive away the coal gas or oxygen-containing flue gas accumulated at the bottom of the outer ash hopper. At the same time, another part passes through the holes of the baffles on both sides of the ash hopper and also gathers into the channel, then rises along the channel and enters the filtration area for filtration. Another part enters the inner ash hopper from the inner ash hopper discharge port or through the holes of the inner ash hopper, drives away the coal gas or oxygen-containing flue gas accumulated in the inner ash hopper and rises into the filtration area for filtration. After efficiently removing particulate matter, it enters the clean gas chamber, and the purified clean gas is discharged from the top air outlet pipe. When the dust collected on the surface of the filter element reaches a certain thickness or the pressure difference reaches a set value, the dust removal device is automatically activated to remove the dust. The removed dust falls into the inner ash hopper, then into the outer ash hopper through the ash outlet at the bottom of the inner ash hopper, and finally is discharged from the ash discharge port at the bottom of the outer ash hopper.

[0021] The beneficial technical effects of this utility model are: it can drive away the coal gas or oxygen-containing flue gas remaining inside the dust collector in real time, effectively reducing the probability of coal gas and oxygen contact and mixing, avoiding combustion and explosion accidents, and significantly improving the safety of the equipment; at the same time, it reduces the amount of dust-laden airflow scouring the filter bag and causing it to fail prematurely, extending the filter bag life, and also helps to reduce operating resistance and energy consumption, so as to achieve safe, efficient, energy-saving and economical operation of the converter gas bag dust collector. Attached Figure Description

[0022] Figure 1 This is a structural diagram of a bag filter for purifying converter gas in steelmaking.

[0023] Figure 2 yes Figure 1 AA section view.

[0024] Figure 3 yes Figure 1 View B in the diagram.

[0025] In the diagram: 1-Inlet duct; 2-Support frame; 3-Outer ash hopper; 4-Inner ash hopper; 5-Ash hopper partition; 6-Inner ash hopper ring beam; 7-Channel partition; 8-Middle box; 9-Filter element; 10-Tube plate; 11-Clean air chamber; 12-Manhole; 13-Dust removal device; 14-Explosion relief device; 15-Outlet duct; 16-Ventilation pipe. Detailed Implementation

[0026] The specific embodiments of this utility model are further described below with reference to the accompanying drawings. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of protection of this utility model. Furthermore, it should be understood that after reading the teachings of this utility model, those skilled in the art can make various alterations or modifications to this utility model, and these equivalent forms also fall within the scope defined by the appended claims.

[0027] like Figure 1 , Figure 2 , Figure 3 A bag filter for purifying converter gas in steelmaking includes an inlet pipe 1, a support frame 2, an outer ash hopper 3, an inner ash hopper 4, an ash hopper partition 5, an inner ash hopper ring beam 6, a channel partition 7, a middle box 8, a filter element 9, a tube sheet 10, a clean air chamber 11, a manhole 12, a dust removal device 13, an explosion relief device 14, an outlet pipe 15, and a vent pipe 16.

[0028] The middle box 8 is welded to the bottom support frame 2. An outer ash hopper 3 is installed at the bottom of the middle box 8, and a tube sheet 10 is welded to the top of the tube sheet 8. A detachable filter element 9 is sealed and installed in the tube sheet hole on the tube sheet 8. A clean air chamber 11 is welded to the top of the tube sheet 8. A dust removal device 13 is installed inside and outside the clean air chamber 8. An air outlet duct 15 and a vent pipe 16 are installed on the top of the clean air chamber 8. The air inlet duct 1 is located on the lower side of the middle housing 8, between the inner ash hopper 4 and the outer ash hopper 3. The inner ash hopper ring beam 6 is located in the cavity between the filter element 9 inside the middle housing 8 and the air inlet duct 1 of the outer ash hopper 3, with the inner ash hopper 4, which has an opening on the windward side, welded to its lower part. The ash hopper partition 5 is spatially perpendicular to the air inlet duct 1 and is installed on the longitudinal section of the center on both sides between the inner ash hopper 4 and the outer ash hopper 3. The channel partition 7 is installed on the upper part of the inner ash hopper ring beam 6 opposite to the air inlet duct 1, and is located in the arc-shaped cavity between the filter area inside the middle housing 8 and the wall panel of the middle housing 8. The manhole door 12 is welded to the lower side of the middle housing 8 and the clean air chamber 11, respectively. The explosion relief device 14 is installed on the upper side of the middle housing 8 and the top of the clean air chamber 11.

[0029] Device installation: The middle box 8 is welded to the support frame 2, and the outer ash hopper 3 is installed at the bottom of it. The air inlet pipe 1 is welded to the lower side. The inner ash hopper ring beam 6 is welded and installed in the cavity between the upper part of the air inlet pipe 1 and the lower part of the filter element 9 inside the middle box 8. The inner ash hopper 4 is welded and installed at the lower part of the inner ash hopper ring beam 6. Two ash hopper partition plates 5 are welded on the longitudinal section of the center on both sides between the inner ash hopper 4 and the outer ash hopper 3 and in a spatially perpendicular manner to the air inlet pipe 1. The channel partition plate 7 is welded and installed above the inner ash hopper ring beam 6 opposite to the air inlet pipe 1.

[0030] A manhole door 12 is welded to the lower side of the middle chamber 8, and an explosion venting device 14 is welded to the upper side. A tube sheet 10 is welded to the upper part of the middle chamber 8. Filter elements 9 are installed on the holes of the tube sheet, and a clean air chamber 11 is welded to the upper part of the tube sheet 10. A pulse jet cleaning device 13 is installed inside and outside the clean air chamber 11. A manhole door 12 is welded to the lower side, and an exhaust pipe 15, an explosion venting device 14, and a vent pipe 16 are welded to the top. After the above installation is completed, a complete bag filter for converter gas purification is formed.

Claims

1. A baghouse dust collector for purifying converter gas in steelmaking, comprising an inlet pipe (1), a support frame (2), an ash hopper, a middle box (8), a filter element (9), a tube sheet (10), a clean gas chamber (11), a manhole (12), a dust removal device (13), an explosion relief device (14), an outlet pipe (15), and a vent pipe (16), wherein the middle box (8) is welded to the support frame (2) at the bottom, and a tube sheet (10) is welded to the top, with a detachable filter element (9) sealed on the holes of the tube sheet, and a clean gas chamber (11) is welded to the top of the tube sheet (10), with a dust removal device (13) installed inside and outside the clean gas chamber (11), and an outlet pipe (15) and a vent pipe (16) installed on the top of the clean gas chamber (11), characterized in that... The ash hopper is a double-layer structure consisting of an inner ash hopper (4) and an outer ash hopper (3). The middle box (8) is a cylindrical structure. An ash hopper partition (5) is provided between the inner ash hopper (4) and the outer ash hopper (3). The inlet of the air inlet pipe (1) is located on the lower part of the middle box (8) or the upper side of the outer ash hopper (3), and is located on the side wall between the inner ash hopper (4) and the outer ash hopper (3). The inner ash hopper (4) has an opening on the windward side. The ash hopper partition (5) and the air inlet pipe (1) are spatially perpendicular and are separately installed. On the longitudinal cross-section of the center on both sides between the inner ash hopper (4) and the outer ash hopper (3); an inner ash hopper ring beam (6) is set in the cavity between the filter element (9) in the middle box (8) and the air inlet pipe (1) of the outer ash hopper (3); an inner ash hopper (4) with an opening on the windward side is welded and installed at the lower part of the inner ash hopper ring beam (6); a baffle plate (7) is installed in the arc-shaped cavity between the inner ash hopper ring beam (6) opposite to the air inlet pipe (1) and the outer filtration area of ​​the middle box (8) and the wall panel of the middle box (8).

2. A bag filter for cleaning the gas from a steelmaking converter, according to claim 1, characterized in that The ash hopper partition (5) has an upper and lower opening structure, and the installation height extends from the lower part of the inner ash hopper ring beam (6) to the outlet of the inner ash hopper (4), with an opening rate of 20%~80%.

3. A bag filter for cleaning the gas from a steelmaking converter, according to claim 1, characterized in that The inner ash hopper (4) has a structure with openings at the top and bottom of the windward side wall, with an opening rate of 10% to 60%.

4. A bag filter for cleaning the gas from a steelmaking converter, according to claim 1, characterized in that The clean air chamber (11) is a cylindrical structure with a cap.

5. A bag filter for cleaning of converter gas in steelmaking according to claim 1, characterized in that: The clearance between the inner ash hopper ring beam (6) and the bottom outer wall of the filter element (9) is ≥50mm.

6. A bag filter for cleaning the gas from a steelmaking converter, according to claim 1, characterized in that The clearance between the baffle plate (7) and the outer wall of the nearest filter element (9) is ≥50mm.

7. A bag filter for cleaning the gas from a steelmaking converter, according to claim 1, characterized in that The manhole door (12) is welded to the lower side of the middle box (8) and the clean air chamber (11); the explosion relief device (14) is installed on the upper side of the middle box (8) and the top of the clean air chamber (11).

8. A bag filter for cleaning the gas from a steelmaking converter, according to claim 1, characterized in that The explosion relief device (14) is of the diaphragm type, the hammer type, or the spring type.

9. A bag filter for cleaning the gas from a steelmaking converter, according to claim 1, characterized in that The dust removal device (13) uses pulse jet cleaning and sonic cleaning as its cleaning methods, and the air source for pulse jet cleaning is inert gas.

10. A bag filter for cleaning the gas from a steelmaking converter, according to claim 1, characterized in that The filter element (9) is made of filter material containing ceramic and metal materials according to the flue gas temperature. Its temperature resistance range is 150℃~500℃, and it adopts a circular filter bag or filter cylinder structure.

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