RU75586U1 - GAS CLEANING FILTER WITH PULSE REGENERATION - Google Patents

Abstract

The device is intended for regeneration systems of filtering filter elements operated in dust and aerosol systems for cleaning gas-air-dust flows.

The objective of the proposed solution is to develop a system for the regeneration of filtering filter elements with the following qualities: does not complicate the installation of the filtering elements themselves; does not increase aerodynamic resistance of the outlet of purified air from the sleeves; minimizes the consumption of compressed air for regeneration; provides supersonic air velocity from the nozzle; has a high pulse energy; does not lead to strong stretching of the material of the filter element.

The task is achieved in that in a filter for gas purification with pulse regeneration, containing several filter modules, including several filter elements, a dust hopper and a dust discharge device, a line for supplying dust-saturated gases with nozzles for supplying to each module, and a line for removing purified gases with branch pipes for exhausting of each module, the filter has a system of regeneration of filter elements using pulses of compressed air, including a receiver of compressed air connected through valves to dispensing pipes equipped with nozzles located above the outlet of each filter element, each nozzle being made in the form of a “Laval nozzle”.

Description

The device is intended for regeneration systems of filtering filter elements operated in systems for cleaning gas and air-dust flows from dust and aerosols.

From the sources of scientific, technical and patent information, a large number of various designs of regeneration systems of filtering filter elements are known, in which the so-called "Venturi pipe" is used, which is described in various sources as an ejection nozzle or diffuser. It is used in pulsed regeneration systems of filter elements. Cleaning occurs due to the kinetic energy of a short-term pulse of compressed air or gas into the internal cavity of the filter element.

The energy of a short pulse of compressed air or gas is determined by the formula:

wherein M _WHO - body weight, generating a pulse in this case the air flow from the nozzle;

w is the speed of the body, in our case, the rate of air flow from the nozzle.

A bag filter is known comprising a housing with symmetrically filtering sections located in it, between which a dusty gas collector runs horizontally in the lower part and a purified gas collector in the upper part. Each of the filter sections includes a dusty gas chamber with a set of vertically oriented filter bags with a purified gas chamber located on top and a dust collection bin located on top of it, which communicates with the dusty gas collector through the slotted passage located between them. In addition, there is a regeneration system for filter bags. In this case, the side walls between the dust collector collector and dusty gas chambers are perforated to enter the last parts of the dusty gas, bypassing the hopper. The ratio of the orifice of the holes (perforations) in the walls of the dust collector to the section of the slot passage in the hopper in each filter section is approximately 1: 1. The filter bag regeneration system includes at least one compressed air receiver connected through at least one electrically actuated diaphragm valve with purge pipes containing nozzles, each of which is directed to the open end part of the filter bag from the side of the cleaned manifold gas. Each filter section is equipped with a pneumatic actuator kinematically connected with

shut-off rotary damper, to isolate the purified gas chamber from the purified gas manifold during the regeneration of filter bags (see RF patent No. 2179879, IPC B01D 46/02).

This design has a serious drawback: during operation of bag filters, its regeneration is deteriorated due to the weak ejection effect when a stream of compressed air from the nozzle of the distribution pipe enters the openings of the sleeve.

A known filter comprising a housing with a grill separating it into dusty and purified gas chambers, filter bags, frames with ejecting nozzles and a regenerating device. Thin plates are installed inside the ejection nozzles perpendicular to the flow of compressed air (see RF patent No. 2276618, IPC B01D 46/02).

This filter contains ejection nozzles, but the pulse energy is spent on oscillating perpendicularly mounted plates and, accordingly, the regeneration from the pulsed discharge goes into the discharge of mechanical regeneration with all its disadvantages.

Closest to the claimed device is a bag filter including a filter sleeve, dispensing pipes with nozzles, means for attaching the sleeve to the sleeve plate, a diffuser and a sectional composite frame fitted with filter fabric. In order to increase the efficiency of the regeneration of the sleeves, increase the reliability of the filter and simplify the replacement of the sleeves, the upper section of the frame does not reach the sleeve plate by 50–300 mm, and the lower end of the last section is inserted into the glass with a wall height 10–100 mm greater than the total the gaps between the protrusions of the diffuser and the upper part of the first section and between the flange of the diffuser and the stop attached to the distribution pipe. A nozzle with a sharp edge connected to the nozzle of the distributing pipe is installed at the bottom of the glass in the center (see RF patent No. 2257941, IPC B01D 46/02).

However, the inventive device has the following disadvantages:

- complexity of installation - to install this type of sleeve, at least two people are needed, one installs a sleeve with a frame on top, the second - from the bottom, ensures that the center of the bottom of the sleeve hits the lower nozzle;

- low regeneration efficiency at two points of supply of compressed air, since the ejection gap at the diffuser is small and also limited by stops, and there is absolutely no in the lower part of the diffuser;

- increased consumption of compressed air for regeneration from two points;

- subsonic speed of air outflow from nozzles;

- increased consumption of compressed air from two points leads to a strong inflation of the sleeve, which in turn leads to stretching of the filter material and, accordingly, reducing the service life of the filter element;

- high aerodynamic resistance of the cleaned air leaving the sleeve due to the pinch of the diffuser and stops.

The objective of the proposed solution is to develop a system for the regeneration of filtering filter elements with the following qualities:

- does not complicate the installation of the filter elements themselves;

- does not increase the aerodynamic resistance of the outlet of purified air from the sleeves;

- minimizes the consumption of compressed air for regeneration;

- provides supersonic speed of air outflow from the nozzle;

- has a high pulse energy;

- does not lead to strong stretching of the material of the filter element.

The technical result consists in the ease of installation of the filter elements, in reducing the consumption of compressed air for regeneration during supersonic air outflow from the nozzle and the high energy of the regenerating pulse, while maintaining the material properties of the filter element.

The task is achieved in that in a filter for gas purification with pulse regeneration, containing several filter modules, including several filter elements, a dust hopper and a dust discharge device, a line for supplying dust-saturated gases with nozzles for supplying to each module, and a line for removing purified gases with branch pipes for exhausting of each module, the filter has a system of regeneration of filter elements using pulses of compressed air, including a receiver of compressed air connected through valves to dispensing pipes equipped with nozzles located above the outlet of each filter element, each nozzle being made in the form of a “Laval nozzle”.

The utility model is illustrated in the drawing, where:

1. filter housing;

2. panel mounting;

3. filter elements;

4. polluted air compartment;

5. compartment of purified air;

6. partition in the dirty compartment;

7. partition in a clean compartment;

8. filter modules;

9. a line for supplying dusty gas;

10. disconnecting device of the supply line;

11. The line of removal of purified gas;

12. disconnecting device of the branch line;

13. dust collecting bin;

14. dust collecting device;

15. distribution pipes of compressed air;

16. outlet pipe of the filter element;

17. nozzle in the form of a "Laval nozzle";

18. receiver of compressed air;

19. electromagnetic or pneumatic valve;

20. control device;

21. drive disconnecting devices;

22. gas supply pipes;

23. gas outlet pipes.

The device contains a filter housing 1, which is divided by a panel 2 of the filter elements 3 into a compartment of polluted air ("dirty") 4 and a compartment of purified air ("clean") 5. In addition, the partitions located in the dirty 6 and clean 7 compartments of the filter divided into several (at least two) filter modules 8 in which several filter elements 3 are located. Each filter module with a “dirty” compartment 4 is connected to the supply line 9 of dust-saturated gas through a gas supply pipe 22 with a disconnecting device 10 and a clean ”compartment 5 to the outlet line 11 of the cleaned gas, also through the outlet pipe 23 with the disconnecting device 12. The“ dirty ”compartments 4 of the filter modules 8 at the bottom end with the dust hopper 13 and the dust-discharge device 14. The“ clean ”compartments 5 of the filter modules 8 are equipped with dispensers pipes 15 of compressed air, in which opposite each outlet pipe 16 of the filter element 3 is a nozzle 17 for the flow of compressed air. Compressed air for the regeneration of the filter elements is fed into the transfer pipe from the compressed air receiver 18 using an electromagnetic or pneumatic valve 19 opened by the filter regeneration control device 20, the disconnecting devices 10 and 12 are equipped with a drive 21.

The device operates as follows. The flow of dust-saturated gas from the supply line 9 through the gas supply pipe 22 with a disconnecting device 10 is supplied to

“Dirty” compartment 4 of one or more filter modules. One filter module at this time is disconnected both on the supply and on the gas outlet.

Part of the dust, due to the top, relative to the filter elements, supply of dust-saturated gas is naturally deposited on the bottom of the hopper 13, and the main part, entrained by the gas, falls on the outer surface of the filter elements 3. Passing through the filter material of the filter elements 3, the dust-saturated gas is cleaned of dust, enters the "clean" compartment 5 and through the outlet pipe 23 with the open disconnecting device 12 and the exhaust gas outlet line 11 leaves the filter. With an increase in the thickness of the dust layer captured by the filtering elements 3, the aerodynamic resistance of the filter increases and when it reaches a certain maximum working value set in the filter regeneration control device 20, this device sends signals “to close” to the drive 21 of the switching device 10 and 12 of the filter module , which is in operation and signals “to open” to the drive 21, disconnecting devices 10 and 12 of the filter module, which are previously being regenerated. After the shut-off devices 10 and 12 of the filter module are closed, the filter regeneration control device 20 sends sequential signals to briefly open the electromagnetic or pneumatic valves 19 to supply a pulse of compressed air through the transfer pipes 15 and nozzles 17 to the outlet pipes 16 of the filter elements 3. Compressed pulse energy air is determined in this case, the rate of flow of compressed air from the nozzle. In aerodynamics, only one nozzle is known, which makes it possible to create a velocity of air outflow exceeding the speed of sound propagation in a given medium, i.e. in the air. This is the so-called "Laval nozzle." Its design characteristics determine how much the speed of air outflow from the nozzle exceeds the speed of sound. The ratio of the velocity of air to the speed of sound is called the Mach number.

For example, to obtain the pulse energy twice as high as what is set in the prototype at the sound velocity of the air flowing out of the nozzle, it is necessary to double the air flow rate, while maintaining the air flow rate in the inventive device, it is necessary to increase its flow rate by only 1.4 times, i.e. so that the "Mach number" is 1.4. When increasing the pulse energy by 4 times in the prototype, it is necessary to increase air consumption by 4 times, and in the inventive device to bring the value of the "Mach number" to 2 with the same air flow.

In addition, this device does not stretch the material of the filter element, since it does not inflate it, but creates a “standing pressure wave” inside the element,

which moves along the entire length of the element and through the porous structure of the filter material acts on the outer layer of dust and dumps it from the surface of the filter element.

There may be several regeneration cycles. In addition, there is a pause during which the shaken dust settles into the dust collector 13 for subsequent removal by the dust-collecting device 14, which is turned on only when the filter module is turned off for regeneration.

The proposed device of the regeneration system allows for the ease of installation of the filter elements, low consumption of compressed air to effectively regenerate the material of the filter elements, while not violating its properties, thereby allowing to extend their service life and increase the efficiency of the filter as a whole.

Claims (1)

A filter for gas purification with pulse regeneration, characterized in that it contains several filter modules, including several filter elements, a dust collector and a dust discharge device, a line for supplying dust-saturated gases with nozzles for supplying to each module, and a line for removing purified gases with branch pipes for exhausting from each module , the filter has a system for regenerating filter elements using pulses of compressed air, including a receiver of compressed air connected through valves to the dispensing pipe s equipped with nozzles arranged over the outlet of each filter element, wherein each nozzle is configured as a "Laval nozzle".