A double-layer electrostatic precipitator

Abstract

The present invention discloses a double-layer electrostatic precipitator, which comprises a housing, an air inlet, an air outlet and a plurality of electric fields. The air inlet and the air outlet are respectively arranged at the front and rear ends of the housing. A hopper corresponding to each electric field is arranged at the lower end of the housing. Electric fields are arranged in the housing from front to back in sequence. Each electric field includes two sets of anode systems and one set of cathode system arranged up and down. The two sets of anode systems share one set of cathode system. Compared with the prior art, it has good dust cleaning effect, improved adaptability and electrostatic precipitation performance.

Description

Technical Field

[0001] The present invention relates to the technical field of flue gas pollutant treatment, particularly to the technical field of a double-layer electrostatic precipitator.

Background Art

[0002] An electrostatic precipitator utilizes the adsorption effect of a high-voltage electric field on charged dust to separate the dust from the dust-containing gas. It has the advantages of high dust removal efficiency, low pressure loss, low operating cost, and wide application range. However, conventional electrostatic precipitators have technical bottlenecks such as secondary dust re-entrainment and the inability to stably achieve a discharge of 10 mg / m3 at the outlet for a long time.

[0003] With the implementation of the "dual carbon" requirements, there are more and more projects based on the co-firing of biomass such as sludge, garbage, and straw. Especially for large coal-fired units around big cities such as Shanghai, Beijing, and Shenzhen, different proportions of sludge and garbage co-firing are required. After the co-firing of sludge or garbage, the moisture content of the flue gas increases, and the dust adhesion significantly improves. Currently, in conventional electrostatic precipitators, serious ash accumulation on the anode plates occurs and effective ash cleaning cannot be achieved.

[0004] The Russian double-layer electrostatic precipitator adopts a simple way of stacking two electrostatic precipitators vertically. There were also several application performances in China in the early years. It is equipped with upper and lower ash hoppers. Although it can save the planar square space, due to the overall vertical stacking, it has disadvantages such as large steel consumption, complex system, high cost, and is not suitable for the transformation of existing units.

[0005] Currently, electrostatic precipitators include W-type, 480C-type, etc. Due to limitations such as processing technology and anode plate precision, the height of the anode plate is generally below 15 meters. On the other hand, in the working condition of high-adhesion dust and when the anode plate height is higher than 15 meters, the rapping effect is significantly limited. Due to these two reasons, due to the limitation of the anode plate height, the effective height of the electric field of existing electrostatic precipitators is generally below 15 meters, and the electric field height is limited.

[0006] The higher the anode plate height, the greater the processing difficulty and the lower the precision, which affects the precision of the internal electrode spacing of the electrostatic precipitator. The electrode spacing directly affects the electric field current-voltage characteristics, thereby affecting the electrostatic precipitation performance.

[0007] Therefore, a double-layer electrostatic precipitator with good ash cleaning effect, improved adaptability, and electrostatic precipitation performance is needed.

Summary of the Invention

[0008] The purpose of the present invention is to solve the problems in the prior art and propose a double-layer electrostatic precipitator with good ash cleaning effect, improved adaptability, and electrostatic precipitation performance.

[0009] To achieve the above object, the present invention provides a double-layer electrostatic precipitator, comprising a housing, an air inlet, an air outlet and a plurality of electric fields. The air inlet and the air outlet are respectively arranged at the front and rear ends of the housing. A hopper corresponding to each electric field is arranged at the lower end of the housing. Electric fields are arranged in the housing from front to back in sequence. Each electric field includes two sets of upper and lower anode systems and one set of cathode system, and the two sets of anode systems share one set of cathode system.

[0010] Preferably, the anode system includes a plurality of anode plates arranged in parallel at intervals and an anode rapping device for rapping the anode plates.

[0011] Preferably, the anode rapping device includes a reduction motor, a transmission shaft and a plurality of rapping hammers. The reduction motor drives the transmission shaft to rotate, and the rapping hammers are arranged in a staggered manner on the transmission shaft.

[0012] Preferably, the upper end of the anode plate is hinged to a corresponding hanging beam, a reinforcing beam is arranged at the lower end of each anode plate, and an anode rapping head is arranged at one end of the reinforcing beam.

[0013] Preferably, the cathode system includes a plurality of cathode wires arranged in parallel at intervals and a cathode rapping device for rapping the cathode wires and located above them. The cathode wires and the anode plates are arranged alternately, and cathode rapping heads are arranged at the upper ends of the cathode wires.

[0014] Preferably, the cathode rapping device has the same structure as the anode rapping device.

[0015] Preferably, a main beam for installing the cathode wires and the upper anode plates is arranged at the upper end of the housing, and the cathode wires are arranged on the main beam through a plurality of insulating seats.

[0016] Preferably, two support beams are arranged below the upper and lower sets of anode systems in the housing, and limit grooves corresponding to the reinforcing beams are arranged on the support beams.

[0017] Preferably, an installation beam for installing the lower anode plates is arranged in the housing, and flow guide plates are arranged at the front ends of the installation beams.

[0018] Preferably, a gap is left between the anode plates of the upper anode system and the anode plates of the lower anode system, and the anode rapping devices of the upper and lower sets of anode systems do not operate simultaneously for rapping.

[0019] The beneficial effects of the present invention are as follows: 1. The upper and lower sets of anode systems share one set of cathode system, which reduces the overall length of a single anode plate, can effectively transmit the rapping acceleration, and has a good dust cleaning effect.

[0020] 2. The effective height of the electric field of the electrostatic precipitator can reach about 10 - 30 meters. When the electric field height increases under the condition of the same dust removal efficiency, the area of the equipment around can be reduced, the site usage area can be decreased, and the adaptability of the electrostatic precipitator can be improved. Especially, it is suitable for the situation where the site of the renovation project is limited, and the adaptability can be enhanced.

[0021] 3. The height of the anode plate is reduced, the processing difficulty is decreased, the precision is improved, and the change of the electrode spacing in the up - down direction caused by thermal expansion is reduced, which is beneficial to ensuring the electrode spacing precision inside the electrostatic precipitator, thereby improving the electric field current - voltage characteristics and the electrostatic precipitation performance.

[0022] 4. The secondary dust emission is small. The secondary dust emission caused by rapping can be reduced, and the fluctuation of the dust concentration at the outlet beyond the design requirements can be avoided. Because when the upper - layer anode plate is rapped, the lower - layer anode plate is not rapped, and the lower - layer anode plate can effectively absorb the secondary dust generated by the rapping of the upper - layer anode plate, thus reducing the amount of secondary dust emission.

[0023] 5. It has strong renovation adaptability. It can be renovated for the electrostatic precipitators on the current market, and the renovation is simple with low renovation cost.

[0024] 6. The upper and lower two - layer anode systems jointly adopt a set of cathode systems. It avoids the need to independently equip insulation devices, power supply systems and other equipment for two sets of cathode systems, and avoids the problems of complex layout and high cost.

[0025] 7. The cathode rapping device is arranged above the cathode wire, effectively utilizing the height space of the main beam.

[0026] 8. There is a gap between the upper anode plate and the lower anode plate, which is used to reserve the thermal expansion amount space formed by the high flue gas temperature of the upper - row anode plate. Advantages: First, when the electrode plate expands due to heat, it does not affect the electrode spacing; Second, during rapping, the attenuation of the rapping acceleration at the upper end is relatively small.

[0027] 9. The deflector plate avoids the flue gas vertically scouring the installation beam, resulting in the wear of the installation beam, and avoids the vertical blockage of the air flow by the installation beam, resulting in the chaos of the flow field.

[0028] The features and advantages of the present invention will be described in detail through embodiments in combination with the drawings.

Description of the Drawings

[0029] Figure 1 is the structural schematic diagram of a double - layer electrostatic precipitator of the present invention;

[0030] Figure 2 is Figure 1 the enlarged view of A in

[0031] Figure 3 the layout diagram of the anode plate and the cathode wire in the same electric field;

[0032] Figure 4 It is a structural schematic diagram of the anode rapping device.

[0033] In the figure: 1 - housing, 2 - air inlet, 3 - exhaust outlet, 4 - electric field, 5 - ash hopper, 6 - main beam, 7 - insulating seat, 8 - support beam, 9 - limit groove, 10 - mounting beam, 11 - gap, 12 - baffle plate, 41 - anode system, 42 - cathode system, 411 - anode plate, 412 - anode rapping device, 413 - hanging beam, 414 - strengthening beam, 415 - anode rapping head, 421 - cathode wire, 422 - cathode rapping device, 423 - cathode rapping head, 4121 - reduction motor, 4122 - transmission shaft, 4123 - rapping hammer.

Specific implementation manner

[0034] Refer to Figure 1 , Figure 2 , Figure 3 and Figure 4, a double-layer electrostatic precipitator of the present invention includes a housing 1, an air inlet 2, an exhaust outlet 3 and a plurality of electric fields 4. The air inlet 2 and the exhaust outlet 3 are respectively provided at the front and rear ends of the housing 1. A hopper 5 corresponding to the electric field 4 one by one is provided at the lower end of the housing 1. The electric fields 4 are arranged in the housing 1 in sequence from front to back. The electric field 4 includes two sets of anode systems 41 arranged up and down and one set of cathode system 42. The two sets of anode systems 41 share one set of cathode system 42. The anode system 41 includes a plurality of anode plates 411 arranged parallel to each other at intervals and an anode rapping device 412 for rapping the anode plates 411. The anode rapping device 412 includes a reduction motor 4121, a transmission shaft 4122 and a plurality of rapping hammers 4123. The reduction motor 4121 drives the transmission shaft 4122 to rotate. The rapping hammers 4123 are arranged staggeredly on the transmission shaft 4122. The upper end of the anode plate 411 is hinged to a corresponding hanging beam 413. A reinforcing beam 414 is provided at the lower end of each anode plate 411. An anode rapping head 415 is provided at one end of the reinforcing beam 414. The cathode system 42 includes a plurality of cathode wires 421 arranged parallel to each other at intervals and a cathode rapping device 422 for rapping the cathode wires 421 and located above them. The cathode wires 421 and the anode plates 411 are arranged alternately. The upper ends of the cathode wires 421 are all provided with cathode rapping heads 423. The structure of the cathode rapping device 422 is the same as that of the anode rapping device 412. A main beam 6 for installing the cathode wires 421 and the upper anode plates 411 is provided at the upper end of the housing 1. The cathode wires 421 are arranged on the main beam 6 through a plurality of insulating seats 7. Two support beams 8 are provided below the two sets of anode systems 41 in the housing 1. Limiting grooves 9 corresponding to the reinforcing beams 414 one by one are provided on the support beams 8. An installation beam 10 for installing the lower anode plates 411 is provided in the housing 1. Deflector plates 12 are provided at the front ends of the installation beams 10. A gap 11 is left between the anode plates 411 of the upper anode system 41 and the anode plates 411 of the lower anode system 41. The anode rapping devices 412 of the two sets of anode systems 41 do not perform rapping work simultaneously.

[0035] Working process of the present invention:

[0036] During the working process of a double-layer electrostatic precipitator of the present invention, the flue gas enters from the air inlet 2, passes through the electric field 4 in sequence for dust removal, and finally discharges from the exhaust outlet 3. The anode rapping device 412 and the cathode rapping device 422 rap the anode plates 411 and the cathode wires 421 respectively for ash cleaning.

[0037] The rapping logic is as follows: for the upper and lower layers of anode plates 411 in the same electric field, the rapping and dust cleaning times of the upper anode plate 411 and the lower anode plate 411 are staggered. When the ash on the upper anode plate 411 falls under rapping, the ultrafine dust that is not easily adsorbed is likely to re-enter the flue gas during the falling process at a relatively high altitude due to the airflow (i.e., secondary dust emission). At this time, the lower anode plate is still in the electric field, and this part of the ultrafine dust can be captured again, thereby reducing the amount of secondary dust emission. In addition, when the front-end electric field is rapped, the downstream electric field is not rapped. The downstream electric field can capture the secondary dust emission from the upstream electric field again, and at the same time avoid the superposition of secondary dust emission caused by simultaneous rapping.

[0038] The above embodiments are illustrative of the present invention, not limiting of the present invention. Any solution obtained by simply transforming the present invention falls within the protection scope of the present invention.

Claims

1. A double-layer electrostatic precipitator, characterized in that: It includes a housing (1), an air inlet (2), an air outlet (3) and a number of electric fields (4). The air inlet (2) and the air outlet (3) are respectively provided at the front and rear ends of the housing (1). A hopper (5) corresponding to the electric field (4) one by one is provided at the lower end of the housing (1). Electric fields (4) are arranged in the housing (1) in sequence from front to back. The electric field (4) includes two sets of upper and lower anode systems (41) and one set of cathode system (42). The two sets of anode systems (41) share one set of cathode system (42). An installation beam (10) for installing the lower anode plate (411) is provided in the housing (1). Deflector plates (12) are provided at the front ends of the installation beams (10). A gap (11) is left between the anode plates (411) of the upper anode system (41) and the anode plates (411) of the lower anode system (41). The anode rapping devices (412) of the two sets of upper and lower anode systems (41) do not carry out rapping work simultaneously.

2. The double-layer electrostatic precipitator according to claim 1, characterized in that: The anode system (41) includes a number of anode plates (411) arranged parallel to and spaced from each other and an anode rapping device (412) for rapping the anode plates (411).

3. The double-layer electrostatic precipitator according to claim 2, characterized in that: The anode rapping device (412) includes a reduction motor (4121), a transmission shaft (4122) and a number of rapping hammers (4123). The reduction motor (4121) drives the transmission shaft (4122) to rotate. The rapping hammers (4123) are arranged in a staggered manner on the transmission shaft (4122).

4. The double-layer electrostatic precipitator according to claim 2, characterized in that: The upper end of the anode plate (411) is hingedly connected to a corresponding hanging beam (413). A reinforcing beam (414) is provided at the lower end of each anode plate (411). An anode rapping head (415) is provided at one end of the reinforcing beam (414).

5. The double-layer electrostatic precipitator according to claim 1, characterized in that: The cathode system (42) includes a number of cathode wires (421) arranged parallel to and spaced from each other and a cathode rapping device (422) for rapping the cathode wires (421) and located above them. The cathode wires (421) and the anode plates (411) are arranged alternately. Cathode rapping heads (423) are provided at the upper ends of the cathode wires (421).

6. The double-layer electrostatic precipitator according to claim 5, characterized in that: The structure of the cathode rapping device (422) is the same as that of the anode rapping device (412).

7. The double-layer electrostatic precipitator according to claim 1, characterized in that: A main beam (6) for installing the cathode wires (421) and the upper anode plates (411) is provided at the upper end of the housing (1). The cathode wires (421) are arranged on the main beam (6) through a number of insulating seats (7).

8. The double-layer electrostatic precipitator according to claim 1, characterized in that: Two support beams (8) are provided below the two sets of upper and lower anode systems (41) of the housing (1). Limiting grooves (9) corresponding to the reinforcing beams (414) one by one are provided on the support beams (8).

Images