A special electrostatic precipitator for sintering machine head converted into a bag filter

Abstract

This invention relates to the field of industrial dust removal technology, and in particular to a special electrostatic precipitator converted to a bag filter for sintering machine heads. It includes a collector for capturing sparks and large particles, an inlet connected to a dust collector inlet duct, and an outlet connected to a middle chamber with an internal flue gas filtration structure. The collector contains a labyrinth-type airflow distribution device, a dust hopper at the bottom of the collector, a dust hopper at the bottom of the middle chamber, and an upper chamber at the top of the middle chamber. The upper chamber is connected to a clean air emission system and a backflushing system. This special electrostatic precipitator for sintering machine heads features spark and large particle capture, preventing filter bag burning; anti-condensation function to prevent equipment corrosion; high dust removal efficiency and strong operational stability; space-saving design; wider applicability; shorter construction period; lower investment; higher cost-effectiveness; and low operating and maintenance costs. It is suitable for various flue gas environments and can be used in new or retrofit projects.

Description

Technical Field

[0001] This invention relates to the field of industrial dust removal technology, and in particular to a special electrostatic precipitator converted into a bag filter for sintering machine heads. Background Technology

[0002] Currently, due to early technological path dependence, most steel companies primarily use electrostatic precipitators (ESPs) for flue gas treatment at the sintering machine head. While traditional ESPs have certain advantages in handling large-volume, high-concentration flue gas, their dust removal efficiency is greatly affected by operating conditions such as dust resistivity, flue gas temperature, and humidity. This results in numerous drawbacks, including unstable dust removal efficiency, insufficient fine particulate matter removal capacity, high investment and operating costs, and poor adaptability due to large footprint requirements. These limitations are becoming increasingly apparent when facing increasingly stringent emission requirements, especially for high-resistivity dust and fine particulate matter generated by sintering machine heads and coal-fired boilers. ESPs struggle to consistently meet ultra-low emission requirements, placing significant environmental pressure and pollution costs on companies.

[0003] Because baghouse dust collectors have advantages over electrostatic precipitators in terms of dust removal efficiency, emission concentration, and construction investment, replacing electrostatic precipitators with baghouse dust collectors is an inevitable trend. However, conventional baghouse dust collectors cannot avoid the risk of large dust particles containing sparks in the flue gas burning the filter bags. In order to better meet production needs, and considering the characteristics of the flue gas at the sintering machine head, there is an urgent need for a new type of dust collector that can replace electrostatic precipitators. Summary of the Invention

[0004] This invention provides a special electrostatic precipitator for sintering machine head, designed to remove sparks and large particles from the flue gas at the sintering machine head and effectively filter the flue gas to meet stringent ultra-low emission requirements.

[0005] The present invention provides a special electrostatic precipitator for sintering machine head converted to a bag filter, which adopts the following technical solution: A special electrostatic precipitator for sintering machine head, comprising a collector for capturing sparks and large particles, an inlet duct for the collector connected to the dust collector, an outlet connected to a middle chamber with an internal flue gas filtration structure, a labyrinth-type airflow distribution device inside the collector, a dust hopper at the bottom of the collector, a dust hopper at the bottom of the middle chamber, an upper chamber at the top of the middle chamber, and a clean air emission system and a backflushing system connected to the upper chamber.

[0006] Optionally, the clean gas emission system includes a clean gas branch pipe connected to the central housing, a clean gas branch pipe valve installed on the clean gas branch pipe, and if the clean gas branch pipe is connected to a clean gas main pipe, the clean gas main pipe is connected to a fan motor unit, and the fan motor unit is connected to a chimney through a chimney inlet pipe.

[0007] Optionally, the backflushing system includes a backflushing main pipe, one end of which is connected to a clean gas branch pipe via a backflushing branch pipe, with the connection point located at the inlet side of the clean gas branch pipe valve. The other end of the backflushing main pipe is connected to the chimney inlet pipe. A backflushing main pipe valve is installed on the backflushing main pipe, and a backflushing branch pipe valve is installed on the backflushing branch pipe.

[0008] Optionally, the collector also includes a collector flare, the inlet of which is connected to the dust collector's air inlet duct, the outlet of which is connected to the collector housing, a labyrinth-type airflow distribution device inside the collector flare, an anti-condensation device inside the collector housing, and a collector ash hopper located below the collector housing.

[0009] Optionally, the middle box contains a flue body, and a lower conical hopper is provided at the bottom of the flue body along its length. The bottom of the lower conical hopper is connected to the ash hopper through an air inlet pipe.

[0010] Optionally, an airflow distribution plate is installed inside the ash hopper.

[0011] Optionally, the middle chamber is equipped with a perforated plate assembly, filter bags, and bag cages.

[0012] Optionally, the labyrinth-style airflow distribution device includes several profiles arranged in multiple layers in an alternating manner, with the profiles forming a labyrinth-shaped channel.

[0013] Optionally, the anti-condensation device for the trap is equipped with a temperature sensing element and a heating element.

[0014] Optionally, the clean air main pipe is segmented with an increased diameter along the flue gas flow direction.

[0015] In summary, the present invention has at least one of the following beneficial technical effects: 1. It has the function of collecting sparks and large particles to prevent the filter bags from being burned; it has the function of preventing condensation to prevent the equipment from being corroded; it has high dust removal efficiency and strong operational stability. 2. Saves land, has greater applicability, shorter construction period, lower investment, higher cost performance, and lower operation and maintenance costs; 3. Suitable for various flue gas environments, it can be used for both new and renovation projects. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall structure of the sintering machine head-specific electric-to-bag dust collector according to an embodiment of the present invention.

[0017] Figure 2 yes Figure 1 Sectional view along the AA direction.

[0018] Figure 3 This is a schematic diagram of the structure of the labyrinth-type airflow distribution device according to an embodiment of the present invention.

[0019] Explanation of reference numerals in the attached drawings: 1. Steel frame; 2. Dust collector; 201. Dust collector flare; 202. Labyrinth-type airflow distribution device; 203. Dust collector shell; 204. Dust collector hopper; 205. Dust collector anti-condensation device; 3. Dust collector inlet duct; 4. Dust hopper; 401. Dust hopper airflow distribution plate; 5. Middle box; 501. Main flue; 502. Lower conical hopper; 503. Inlet pipe; 6. Tube plate assembly; 7. Filter bag; 8. Bag cage; 9. Upper box; 10. Clean air branch pipe; 101. Clean air branch pipe valve; 11. Clean air main pipe; 12. Backflush main pipe; 121. Backflush main pipe valve; 13. Backflush branch pipe; 131. Backflush branch pipe valve; 14. Fan motor unit; 15. Chimney inlet pipe; 16. Chimney. Detailed Implementation

[0020] The following combination Figures 1-3 The present invention will be described in further detail below.

[0021] This invention discloses a special electrostatic precipitator for sintering machine head, comprising a steel frame 1, a collector 2, a dust collector inlet duct 3, a dust hopper 4, a middle box 5, a tube sheet assembly 6, filter bags 7, bag cages 8, an upper box 9, clean air branch pipes 10, clean air main pipe 11, backflush main pipe 12, backflush branch pipes 13, a fan motor unit 14, a chimney inlet duct 15, and a chimney 16.

[0022] The steel frame 1 provides the installation and support foundation for the main structure of the dust collector. The collector 2 includes a collector bell mouth 201, a labyrinth-type airflow distribution device 202, a collector housing 203, a collector ash hopper 204, and a collector anti-condensation device 205. The inlet end of the collector bell mouth 201 is connected to the dust collector inlet duct 3; the labyrinth-type airflow distribution device 202 is installed inside the collector bell mouth 201. The labyrinth-type airflow distribution device 202 is composed of several profiles arranged in multiple layers in an alternating manner to form a labyrinth-shaped channel. The profiles can be fixed by welding or by detachable connection, such as bolt connection.

[0023] The ash hopper 204 of the collector is located below the collector housing 203; the anti-condensation device 205 of the collector is located inside the collector housing 203. The anti-condensation device 205 is equipped with a temperature detection element and a heating element. When the equipment is restarted after being shut down or when the flue gas temperature is abnormal, the temperature detection element detects that the flue gas temperature inside the collector 2 is lower than the normal operating range. The heating element is activated to heat the collector 2 so that the internal flue gas temperature reaches the normal operating range, preventing the flue gas from condensing inside the collector 2 and corroding the housing. When the internal flue gas temperature of the collector 2 reaches the normal operating range, the heating element is turned off.

[0024] The middle box 5 is connected to the collector housing 203. The middle box 5 is equipped with a flue body 501. Multiple lower conical hoppers 502 are arranged along the length of the bottom of the flue body 501. The bottom of the lower conical hoppers 502 is connected to an air inlet pipe 503. The air inlet pipe 503 is connected to the corresponding ash hopper 4 below. The ash hopper 4 is equipped with an ash hopper airflow distribution plate 401.

[0025] The tube sheet assembly 6 is located inside the middle chamber 5. Filter bags 7 and bag cages 8 are evenly arranged on the tube sheet assembly 6. The filter bags 7 can be fiber filter bags, metal filter bags, or filter cartridges. The upper chamber 9 is installed on top of the middle chamber 5 and is divided into several compartments. Clean air branch pipes 10 correspond one-to-one with the compartments and are connected to the upper chamber 9. The connection points can be on the top or side of the compartment. Clean air branch pipe valves 101 are installed on the clean air branch pipes 10. The clean air branch pipe valves 101 can be electric, pneumatic, hydraulic, etc. The top ends of multiple clean air branch pipes 10 are connected to the clean air main pipe 11. The clean air main pipe 11 is connected to the fan motor unit 14. The fan motor unit 14 is connected to the chimney 16 through the chimney inlet pipe 15. The clean air branch pipes 10, clean air branch pipe valves 101, clean air main pipe 11, fan motor unit 14, chimney inlet pipe 15, and chimney 16 constitute the clean air emission system.

[0026] One end of the backflush main pipe 12 is connected to the chimney inlet pipe 15, and the other end is connected to the backflush branch pipe 13. A backflush main pipe valve 121 is installed on the backflush main pipe 12, which can be manual, electric, pneumatic, hydraulic, or other types. The backflush branch pipe 13 is connected to the clean gas branch pipe 10, and the connection point is located below the clean gas branch pipe valve 101. A backflush branch pipe valve 131 is installed on the backflush branch pipe 13, which can be electric, pneumatic, hydraulic, or other types. The backflush main pipe 12, the backflush main pipe valve 121, the backflush branch pipe 13, and the backflush branch pipe valve 131 constitute the backflush system.

[0027] The implementation principle of the sintering machine head-specific electrostatic precipitator modified into a bag filter according to this invention is as follows: The flue gas path is as follows: flue gas containing sparks and large particles first enters the trap horn 201 for deceleration, and then passes through the labyrinth-type airflow distribution device 202 for multi-stage interception, deflection and deceleration, so that sparks and large particles are effectively captured. Before entering the flue body 501 of the middle box 5, most of the sparks and large particles are left in the ash hopper 204 of the trap.

[0028] Secondary dust inside the collector housing 203 enters the flue body 501 of the middle chamber 5, and then passes through the lower conical hopper 502 and the air inlet pipe 503 in sequence, entering the ash hopper 4 from the top for thorough settling. The settled secondary flue gas is then evenly distributed into each chamber of the middle chamber 5 through the ash hopper airflow distribution plate 401, ensuring thorough filtration. The ash-free diversion flue, composed of the flue body 501, the lower conical hopper 502, and the air inlet pipe 503, not only evenly distributes the flue gas to each chamber but also prevents ash accumulation in the flue, enabling the dust collector to operate stably for a long time.

[0029] The clean air, filtered by the filter bag 7, sequentially enters each compartment of the upper housing 9, the clean air branch pipe 10, the clean air main pipe 11, the fan motor unit 14, the chimney inlet pipe 15, and finally connects to the chimney 16. During normal operation of the dust collector, the clean air branch pipe valve 101 is in the normally open state, and the air volume of each housing can also be adjusted through the clean air branch pipe valve 101.

[0030] The backflushing gas runs along the following route: starting from the inlet pipe 15 of the chimney, it passes through the backflushing main pipe 12 and the backflushing branch pipe 13 in sequence, connecting to the clean gas branch pipe 10, and then enters the upper casing 9.

[0031] The dust collector can perform backflushing cleaning in either timed or pressure-controlled modes, and the backflushing system can be automatically controlled. During normal operation, the main backflushing valve 121 can remain open, while the branch backflushing valve 131 remains closed. When cleaning is required, simply close the clean air branch valve 101, disconnecting the corresponding compartment of the upper housing 9, and open the backflushing branch valve 131. This allows clean air from the chimney inlet pipe 15 to flow back into the corresponding compartment of the upper housing 9. The instantaneous positive pressure airflow fills the compartment, shaking off any agglomerated or accumulated dust from the outer wall of the filter bags 7 into the ash hopper 4, restoring the filter bags 7 to their normal working state. This backflushing method effectively cleans the filter bags 7 while protecting the ash film on their surface, extending their service life.

[0032] The clean air pipeline consisting of clean air branch pipe 10, clean air branch pipe valve 101, and clean air main pipe 11 can be set with different pipe diameters according to actual needs to adapt to the needs of different boxes. In particular, the clean air main pipe 11 can be expanded in sections to better match the air volume required by each box. Moreover, the clean air branch pipe valve 101 can be used as a regulating valve to adjust the flow of each clean air branch pipe 10, so as to realize dynamic control of the entire pipeline network.

[0033] The coarse dust particles inside the ash hopper 204 of the collector can be returned to the sintering batching system for batching or transported for sale. The fine dust particles inside the ash hopper 4 can be used as fuel supplement for sintering or transported for sale, both of which can create certain economic benefits.

[0034] The sintering machine head-specific electrostatic precipitator of this invention features spark and large particle capture functions to prevent filter bags from being burned; it also has anti-condensation function to prevent equipment corrosion; it has high dust removal efficiency and strong operational stability; it saves space, has wider applicability, shorter construction period, lower investment, higher cost performance, and lower operating and maintenance costs; it is suitable for various flue gas environments and can be used in new projects as well as renovation projects.

[0035] The above are all preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Therefore, all equivalent changes made in accordance with the structure, shape and principle of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A special electric bag type dust collector for a sintering machine head, characterized in that: Includes a collector (2) for capturing sparks and large particles. The inlet of the collector (2) is connected to a dust collector air inlet pipe (3). The outlet of the collector (2) is connected to a middle box (5) with an internal flue gas filtration structure. The inside of the collector (2) is equipped with a labyrinth-type airflow distribution device (202). The bottom of the collector (2) is equipped with a collector ash hopper (204). The bottom of the middle box (5) is equipped with an ash hopper (4). The top of the middle box (5) is equipped with an upper box (9). The upper box (9) is connected to a clean gas emission system and a backflushing system.

2. The special electrostatic precipitator for sintering machine head as described in claim 1, characterized in that: The clean gas emission system includes a clean gas branch pipe (10) connected to the middle box (5), a clean gas branch pipe valve (101) installed on the clean gas branch pipe (10), a clean gas main pipe (11) connected to the clean gas branch pipe (10), a fan motor unit (14) connected to the clean gas main pipe (11), and a fan motor unit (14) connected to the chimney (16) through the chimney inlet pipe (15).

3. The special electrostatic precipitator for sintering machine head as described in claim 2, characterized in that: The backflush system includes a backflush main pipe (12), one end of which is connected to the clean gas branch pipe (10) via a backflush branch pipe (13). The connection point is located on the inlet side of the clean gas branch pipe valve (101). The other end of the backflush main pipe (12) is connected to the chimney inlet pipe (15). A backflush main pipe valve (121) is installed on the backflush main pipe (12), and a backflush branch pipe valve (131) is installed on the backflush branch pipe (13).

4. The special electrostatic precipitator for sintering machine head as described in claim 1, characterized in that: The trap (2) also includes a trap horn (201), the inlet of which is connected to the dust collector air inlet pipe (3), the outlet of which is connected to the trap housing (203), a labyrinth-type airflow distribution device (202) is installed inside the trap horn (201), a trap anti-condensation device (205) is installed inside the trap housing (203), and a trap ash hopper (204) is installed below the trap housing (203).

5. The special electrostatic precipitator for sintering machine head as described in claim 1, characterized in that: The middle box (5) is equipped with a flue body (501), and a lower conical hopper (502) is provided at the bottom of the flue body (501) along the length direction. The bottom of the lower conical hopper (502) is connected to the ash hopper (4) through an air inlet pipe (503).

6. The sintering machine head-specific electrostatic precipitator converted to a bag filter according to claim 1 or 5, characterized in that: The ash hopper (4) is equipped with an airflow distribution plate (401).

7. The special electrostatic precipitator for sintering machine head as described in claim 1, characterized in that: The middle box (5) is equipped with a tube sheet assembly (6), filter bags (7) and bag cages (8).

8. The special electrostatic precipitator for sintering machine head as described in claim 1, characterized in that: The labyrinth-type airflow distribution device (202) includes several profiles arranged in multiple layers, forming a labyrinth-shaped channel between the profiles.

9. The special electrostatic precipitator for sintering machine head as described in claim 4, characterized in that: The anti-condensation device (205) of the trap is equipped with a temperature detection element and a heating element.

10. The special electrostatic precipitator for sintering machine head as described in claim 2, characterized in that: The main clean air pipe (11) is segmented and widened along the flue gas flow direction.

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