A device and method for optimizing the operational performance of a baghouse

Abstract

The application discloses a device and method for optimizing operation performance of a bag-type dust collector, and belongs to the technical field of environmental protection engineering. Dust-containing airflow is introduced into the dust collector through an air inlet, and the airflow is uniformly organized by a guide plate, and contacts the surface of filter bags in the upper box of the dust collector to realize interception of dust. When the surface of the filter bag is covered with too thick dust, and the resistance of the filter bag is too large, the nozzle of a blowing pipe is controlled by a pulse valve to blow high-pressure compressed air to clean the dust. The dust falls to a dust storage hopper under the action of gravity, is discharged through a star-shaped dust discharge valve, and is discharged to a spiral dust conveying device. The dust is discharged outside by power-law spiral blades in the spiral dust conveying device. The application can be widely used in dust-containing air purification treatment in the mining and metal smelting industries, greatly improves the effective filtering area of the filter bag, reduces the wear of the filter bag, uniformly distributes the airflow, relieves the dust accumulation and blockage at the dust discharge port of the dust storage bin, realizes stable, continuous and uniform discharge, and further reduces the operation cost of the equipment.

Description

Technical Field

[0001] This invention relates to the field of baghouse dust collector technology, specifically to a device and method for optimizing the operating performance of a baghouse dust collector. Background Technology

[0002] Baghouse dust collectors are currently the most commonly used dry dust collection equipment, characterized by high dust removal efficiency (99.5%-99.95%), wide applicability, stable operation, compact structure, and low cost. The filter bags are made of woven felt fabric. When dust-laden air passes through the filter bags, dust accumulates on the surface due to a combination of inertial collisions and filtration interception. The purified air is then drawn into the atmosphere by a fan.

[0003] Existing conventional bag filters have the following problems:

[0004] 1. The effective filtration area utilization rate of the filter bags is low, only 60-70% of the structural area. On the one hand, the filtration area on the leeward side of the filter bags is not effectively utilized when the dust-laden airflow is turbulent; on the other hand, when too much dust accumulates and the resistance is too high in the front row of filter bags, the airflow of dust-laden air at the rear row of filter bags is insufficient, resulting in the filtration area of ​​the filter bags at this location also not being effectively utilized.

[0005] 2. Uneven airflow organization inside the chamber; the filter bags near the air intake duct experience high airflow speed, high pressure, and severe wear.

[0006] 3. Dust easily accumulates and bridges at the ash discharge port of the ash storage silo, causing material blockage. This is especially noticeable when the dust particle size is too small or the moisture content is too high.

[0007] 4. The screw conveyor blades are of uniform size and feed material at a constant volume. As the dust is continuously compressed, it is easy to cause caking and blockage.

[0008] 5. The existing blowpipes have uniform nozzle diameters, resulting in low airflow at the front end and high airflow at the rear end, leading to uneven airflow distribution. As a result, the front end is not thoroughly cleaned and the rear filter bags are severely damaged. Summary of the Invention

[0009] The purpose of this invention is to provide a device and method for optimizing the operating performance of a bag filter, which has the advantages of high dust removal efficiency, stable operation, and simple maintenance, so as to solve the problems mentioned in the background art.

[0010] To achieve the above objectives, the present invention provides the following technical solution:

[0011] A device for optimizing the operating performance of a baghouse dust collector includes an air inlet duct, an upper housing of the dust collector, and a dust collection hopper. The air inlet duct is located in the middle of the upper housing of the dust collector, and guide plates are provided on both sides of the air inlet duct. The guide plates are connected to the interior of the upper housing of the dust collector. Filter bags are installed inside the upper housing of the dust collector, and the surface of the filter bags is in contact with the guide plates. A blowpipe is provided above the filter bags and is installed at the upper end of the upper housing of the dust collector. Nozzles are spaced apart on the blowpipe and face the filter bags. The end of the blowpipe is connected to an air tank. The air bag is located on one side of the upper housing of the dust collector, and a pulse valve for controlling the operation of the air bag is also installed on the blowpipe; the ash hopper is located below the upper housing of the dust collector for temporary dust storage; the lower end of the ash hopper is provided with a compressed air port for connecting to a compressed air pipeline, and a star-shaped ash discharge valve is installed at the discharge port of the ash hopper to control the dust inside the ash hopper to be discharged into the screw conveyor; the screw conveyor is connected to the discharge port of the ash hopper, and the screw conveyor is provided with blades for discharging dust.

[0012] Furthermore, the guide plate is made of 5mm thick wear-resistant steel plate and is obliquely distributed on both sides of the air inlet duct, with one plate spaced 400-600mm apart. The horizontal installation angle of the upper steel plate is between 40° and 60°, and the horizontal installation angle of the lower plate is between 15° and 40°.

[0013] Furthermore, the filter bags adopt a perforated arrangement, with the pore diameter of the filter bags on both sides increasing from small to large, and the pore diameter of the middle filter bag decreasing from large to small, and the pore diameter grade difference of the filter bags controlled at 50mm-80mm. The outer spacing of the filter bags is 24%-32%Фb mm, where Фb is the larger pore diameter of the filter bag.

[0014] Furthermore, the dust collector is also equipped with a lifting valve for lifting the filter bags on the upper housing.

[0015] Furthermore, the diameter Φ of the spray pipe is 80-120mm, and the openings are on a horizontal line; the diameter of the front end orifice of the nozzle is large, Φ is 10-14mm, and the diameter of the rear end orifice is small, Φ is 6-10mm; the distance between the nozzle and the perforated plate is 250mm-320mm; the nozzle length is 50-60mm; and the spraying pressure is 0.4-0.6MPa.

[0016] Furthermore, the ash hopper is connected to a high-pressure air tank through an external air compression hole with a working pressure of 0.3MPa-0.5MPa, a hole diameter of Ф6-Ф10mm, a vertical installation angle of 10°-15° with the side plate of the ash hopper, and an insertion length of 3-6mm into the ash hopper.

[0017] Furthermore, the spiral ash conveyor is U-shaped with a cover plate on top; its internal blades are power-law spirals, with the front blades having a smaller diameter and the rear blades having a larger diameter.

[0018] Furthermore, the design method of the blade is as follows:

[0019] Step 1: Let the volume of the i-th spiral groove be: Where ν is the axial velocity in m / s; L is the circumferential area of ​​the blade in m². 2 ;t i The transit time (s) for this section of the spiral groove;

[0020] Step 2: Obtain the discharge capacity of the spiral discharge device: Where D is the helix diameter in m; N is the rotational speed in r / min; The filling rate is 0.75-0.90, and ρ is the powder density in kg / m³. 3 C is the tilt coefficient, which ranges from 0.82 to 0.92.

[0021] This invention provides another technical solution: a method for optimizing the operating performance of a bag filter, implemented based on a device for optimizing the operating performance of a bag filter, comprising the following steps:

[0022] Step 1: The dust-laden airflow enters the dust collector through the air inlet duct. The airflow is organized evenly by the guide plate and comes into contact with the surface of the filter bags inside the upper chamber of the dust collector to intercept dust.

[0023] Step 2: When the dust accumulation on the filter bag surface is too thick and the filter bag resistance is too high, the pulse valve controls the nozzle of the blowpipe to blow high-pressure compressed air to clean the dust.

[0024] Step 3: The dust falls into the ash hopper under the action of gravity, and is discharged through the star-shaped ash discharge valve to the screw conveyor, where it is discharged by the power-law spiral blades.

[0025] Compared with the prior art, the beneficial effects of the present invention are:

[0026] The present invention provides an apparatus and method for optimizing the operating performance of a bag filter, which can significantly increase the effective filtration area of ​​the filter bag, reduce filter bag wear, ensure uniform airflow distribution, alleviate dust accumulation and blockage at the ash discharge port of the ash storage hopper, achieve stable, continuous and uniform discharge, and thus reduce equipment operating costs. Attached Figure Description

[0027] Figure 1 This is a front view of the overall structure of the present invention;

[0028] Figure 2 This is a side view of the overall structure of the present invention;

[0029] Figure 3 This is a structural diagram of the perforated filter bag arrangement of the present invention;

[0030] Figure 4This is a diagram showing the airflow organization distribution of the perforated filter bag of the present invention;

[0031] Figure 5 This is a structural diagram of the jet pipe of the present invention.

[0032] In the diagram: 1. Air inlet duct; 2. Guide plate; 3. Upper housing of dust collector; 4. Filter bag; 5. Pulse pipe; 6. Nozzle; 7. Pulse valve; 8. Air tank; 9. Lifting valve; 10. Ash hopper; 11. Compressed air port; 12. Rotary rotary valve; 13. Screw conveyor; 14. Blades. Detailed Implementation

[0033] The technical solutions of the embodiments of the present invention will be clearly and completely described 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.

[0034] Please see Figure 1-5 This invention provides a device for optimizing the operating performance of a baghouse dust collector, comprising an air inlet duct 1, an upper housing 3 of the dust collector, and a dust collection hopper 10. The air inlet duct 1 is located in the middle of the upper housing 3 of the dust collector. Guide plates 2 are provided on both sides of the air inlet duct 1, and the guide plates 2 communicate with the interior of the upper housing 3. Filter bags 4 are provided inside the upper housing 3, and the surface of the filter bags 4 contacts the guide plates 2. A blowpipe 5 is provided above the filter bags 4, and the blowpipe 5 is installed at the upper end of the upper housing 3 of the dust collector. Nozzles 6 are spaced apart on the blowpipe 5, facing the filter bags 4. An air tank 8 is connected to the end of the blowpipe 5, and the air tank 8 is located on one side of the upper housing 3 of the dust collector, mainly for pressure stabilization. The blowpipe 5 is also equipped with… A pulse valve 7 is provided to control the operation of the air tank 8; the ash hopper 10 is located below the upper housing 3 of the dust collector for temporary dust storage; the lower end of the ash hopper 10 is provided with a compressed air port 11 for connecting to a compressed air pipeline, and a star-shaped ash discharge valve 12 is installed at the discharge port of the ash hopper 10 to control the dust inside the ash hopper 10 to be discharged into the spiral ash conveying device 13; the spiral ash conveying device 13 is connected to the discharge port of the ash hopper 10, and the spiral ash conveying device 13 is provided with blades 14 for discharging dust; wherein, the compressed air port 11 sprays air in reverse when dust accumulates and bridges at the discharge port, so that the accumulated dust is loosened and easy to discharge, and the power-law spiral blades 14 achieve stable and continuous discharge.

[0035] In the above embodiment, the guide plate 2 is made of 5mm thick wear-resistant steel plate and is obliquely distributed on both sides of the air inlet duct 1, with one plate spaced 400-600mm apart. The upper steel plate has a larger horizontal installation angle (between 40° and 60°) and the lower plate has a smaller horizontal installation angle (between 15° and 40°), which can reduce the direct impact of high-speed airflow on the surface of the filter bag 4 and reduce damage to the filter bag 4. Under the action of the guide plate 2, the dust-laden airflow can be sprayed into the ash storage bin area, increasing the cross-section and reducing the flow velocity. In addition, it can increase the filtration area of ​​the lower part of the filter bag 4 and improve the effective filtration area of ​​the filter bag 4.

[0036] The filter bags 4 are arranged in a tube sheet configuration to increase the contact area between the dust-laden airflow and the filter bags 4. Numerical simulation results show that the contact area generated by the airflow around the leeward side in a parallel arrangement is only 25%-35% (the higher the wind speed, the smaller the value). The tube sheet arrangement can increase the contact area on the leeward side by 20%-40%, thus increasing the effective filtration area of ​​the filter bags 4 by 15%-22%. The pore diameter of the filter bags 4 on both sides increases from small to large perpendicular to the air inlet direction, while the pore diameter of the middle filter bags 4 decreases from large to small. This reduces the airflow impact on adjacent filter bags 4, reduces the resistance of the front row of filter bags 4, and increases the amount of dust-laden air handled by the rear row of filter bags 4. The pore diameter grade difference of the filter bags 4 is controlled between 50mm and 80mm. The spacing between the outer sides of the filter bags 4 is 24%-32%Фb mm (Фb is the larger pore diameter of the filter bag 4). A lifting valve 9 is also provided on the upper housing 3 of the dust collector for lifting the filter bags 4; the lifting valve 9 is used for compartment cleaning.

[0037] In the above embodiment, the diameter Φ of the blowpipe 5 is 80-120mm, and the openings are on a horizontal line; the diameter of the front orifice of the nozzle 6 is large, Φ is 10-14mm, and the diameter of the rear orifice is small, Φ is 6-10mm. The optimal effect is achieved when the distance between the nozzle 6 and the perforated plate is 250mm-320mm, the length of the nozzle 6 is 50-60mm, and the blowing pressure is 0.4-0.6MPa. This is because the front flow velocity is high and the pressure is low, requiring a larger opening area to force in more compressed air.

[0038] In the above embodiment, the ash hopper 10 is connected to a high-pressure air tank through the outer air compression hole 11. The working pressure is 0.3MPa-0.5MPa, the hole diameter is Ф6-Ф10mm, the vertical installation angle with the side plate of the ash hopper 10 is 10°-15°, and the length of the air hopper extending into the ash hopper 10 is 3-6mm. When the dust accumulates and bridges at the ash discharge port, the compressed powder layer is loosened by spraying a reverse high-pressure airflow, which reduces the density of the pile and facilitates smooth material discharge.

[0039] The spiral ash conveyor 13 in this embodiment of the invention adopts a U-shape with a cover plate on the top. Its internal blades 14 are power-law spirals, with the front blades 14 having a smaller diameter and the rear blades 14 having a larger diameter. This prevents dust from accumulating excessively at the rear of the spiral ash conveyor 13, causing excessive torque on the rotating shaft and potentially burning out the motor. Simultaneously, it effectively ensures uniform and stable unloading and conveying. Based on the aforementioned spiral ash conveyor 13, the blades 14 of this invention can be designed according to the following formula:

[0040] Step 1: Let the volume of the i-th spiral groove be: Where ν is the axial velocity in m / s; L is the circumferential area of ​​the blade in m². 2 ;t i The transit time (s) for this section of the spiral groove;

[0041] Step 2: Obtain the discharge capacity of the spiral discharge device: Where D is the helix diameter in m; N is the rotational speed in r / min; The filling rate is 0.75-0.90, and ρ is the powder density in kg / m³. 3 C is the tilt coefficient, which ranges from 0.82 to 0.92.

[0042] To further explain the embodiments of the present invention, a method for optimizing the operating performance of a bag filter is also provided, which is implemented based on a device for optimizing the operating performance of a bag filter, and includes the following steps:

[0043] Step 1: The dust-laden airflow enters the dust collector through the air inlet duct 1. The airflow is organized evenly by the guide plate 2 and comes into contact with the surface of the filter bag 4 inside the upper chamber 3 of the dust collector to intercept dust.

[0044] Step 2: When the dust accumulation on the surface of filter bag 4 is too thick and the resistance of filter bag 4 is too high, the pulse valve 7 controls the nozzle 6 of the blow pipe 5 to blow high-pressure compressed air to clean the dust; among them, the lifting valve 9 is for compartment cleaning, and the air tank 8 is mainly for stabilizing the pressure.

[0045] Step 3: The dust falls into the ash storage hopper 10 under the action of gravity, and is discharged through the star-shaped ash discharge valve 12 to the screw conveyor 13, where it is discharged by the power-law spiral blades 14.

[0046] Numerical simulation and industrial testing have demonstrated that the device and method for optimizing the operating performance of a bag filter provided by this invention have the following advantages:

[0047] (1) The service life of filter bag 4 is significantly increased, the wear of filter bag 4 is reduced, and the filtration area of ​​filter bag 4 on the leeward side and side wall of the box is effectively utilized.

[0048] (2) The blowing effect of the blowpipe 5 is improved, the air flow distribution is more uniform, and the dust removal effect is more obvious;

[0049] (3) The dust accumulation and blockage at the ash discharge port of the ash storage hopper 10 are relieved, and the star-shaped ash discharge valve 12 at the bottom no longer needs to operate continuously to discharge material, especially when the dust is too wet;

[0050] (4) By combining the power-law spiral blade 14 with the spiral ash conveying device 13, stable, uniform and continuous material discharge was achieved, and the motor burnout phenomenon no longer occurred.

[0051] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A device for optimizing the operating performance of a bag filter, characterized in that, The dust collector includes an air inlet duct (1), an upper housing (3) of the dust collector, and a dust collection hopper (10). The air inlet duct (1) is located in the middle of the upper housing (3) of the dust collector. Guide plates (2) are provided on both sides of the air inlet duct (1). The guide plates (2) are connected to the interior of the upper housing (3) of the dust collector. Filter bags (4) are provided inside the upper housing (3). The surface of the filter bags (4) is in contact with the guide plates (2). A blowpipe (5) is provided above the filter bags (4). The blowpipe (5) is installed at the upper end of the upper housing (3) of the dust collector. Nozzles (6) are provided at intervals on the blowpipe (5) facing the filter bags (4). The end of the blowpipe (5) is connected to an air tank (8). The air tank (8) is located in the dust collector. On one side of the upper housing (3) of the dust collector, a pulse valve (7) for controlling the operation of the air bag (8) is also installed on the blow pipe (5); the ash hopper (10) is located below the upper housing (3) of the dust collector for temporary dust storage; the lower end of the ash hopper (10) is provided with a compressed air hole (11) for connecting to the compressed air pipeline, and a star-shaped ash discharge valve (12) is installed at the discharge port of the ash hopper (10) to control the dust inside the ash hopper (10) to be discharged into the screw conveyor (13); the screw conveyor (13) is connected to the discharge port of the ash hopper (10), and the screw conveyor (13) is provided with blades (14) for discharging dust. The filter bags (4) are arranged in a perforated pattern. The pore size of the filter bags (4) on both sides perpendicular to the air intake direction increases from small to large, while the pore size of the middle filter bag (4) decreases from large to small. The pore size grade difference of the filter bags (4) is controlled between 50mm and 80mm. The outer spacing of the filter bags (4) is 24%-32% Фb mm, where Фb is the larger pore size of the filter bag.

2. The device for optimizing the operating performance of a bag filter as described in claim 1, characterized in that: The guide plate (2) is made of 5mm thick wear-resistant steel plate and is obliquely distributed on both sides of the air inlet duct (1), with one plate spaced 400-600mm apart. The installation horizontal angle of the upper steel plate is 40º-60º, and the installation horizontal angle of the lower plate is between 15º-40º.

3. The device for optimizing the operating performance of a bag filter as described in claim 1, characterized in that: The dust collector upper housing (3) is also equipped with a lifting valve (9) for lifting the filter bag (4).

4. The device for optimizing the operating performance of a bag filter as described in claim 1, characterized in that: The diameter Φ of the blowpipe (5) is 80-120mm, and the openings are on a horizontal line; the diameter of the front end orifice of the nozzle (6) is large, Φ is 10-14mm, and the diameter of the rear end orifice is small, Φ is 6-10mm. The distance between the nozzle (6) and the tube sheet is 250mm-320mm, the length of the nozzle (6) is 50-60mm, and the blowing pressure is 0.4-0.6MPa.

5. The device for optimizing the operating performance of a bag filter as described in claim 1, characterized in that: The ash hopper (10) is connected to the high-pressure air tank through the outer air compression hole (11). The working pressure is 0.3MPa-0.5MPa, the hole diameter is Ф6-Ф10mm, the vertical installation angle with the side plate of the ash hopper (10) is 10º-15º, and the length of the ash hopper (10) extending into the ash hopper (10) is 3-6mm.

6. The device for optimizing the operating performance of a bag filter as described in claim 1, characterized in that: The spiral ash conveying device (13) is U-shaped and has a cover plate on the top; its internal blades (14) are power-law spirals, with the front blades (14) having a smaller diameter and the rear blades (14) having a larger diameter.

7. The device for optimizing the operating performance of a bag filter as described in claim 6, characterized in that: The design method of the blade (14) is as follows: Step 1: Let the volume of the i-th spiral groove be: ;in L is the axial velocity (m / s); L is the circumferential area of ​​the blade (m²). 2 ); The passage time (s) of this spiral groove; Step 2: Obtain the discharge capacity of the spiral discharge device: Where D is the helix diameter (m); N is the rotational speed (r / min); The fill rate, ranging from 0.75 to 0.90, Powder density (kg / m³) 3 C is the tilt coefficient, which ranges from 0.82 to 0.

92.

8. A method for optimizing the operating performance of a bag filter, implemented based on the apparatus for optimizing the operating performance of a bag filter according to any one of claims 1-7, characterized in that, Includes the following steps: Step 1: The dust-laden airflow enters the dust collector through the air inlet duct (1), and the airflow is organized evenly by the guide plate (2), so that it comes into contact with the surface of the filter bag (4) inside the upper box (3) of the dust collector to intercept dust; Step 2: When the dust accumulation on the surface of the filter bag (4) is too thick and the resistance of the filter bag (4) is too high, the nozzle (6) of the blow pipe (5) is controlled by the pulse valve (7) to blow high-pressure compressed air to clean the dust. Step 3: The dust falls into the ash hopper (10) under the action of gravity, and is discharged to the screw conveyor (13) after being discharged through the star-shaped ash discharge valve (12). The dust is then discharged by the power-law spiral blades (14) inside the screw conveyor (13).

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