CN201105920Y - A dust removal system of a pneumatic ash conveying device - Google Patents

Abstract

The utility model discloses a dust removal system of a pneumatic ash conveying device, which mainly comprises: a dust removal fan, a dust collector connected with the dust removal fan, a pneumatic ash conveying device located below the dust collector, an ash storehouse connected with the pneumatic ash conveying device, and The main feature is that there is an exhaust gas collection port on the ash storage, which communicates with the dust collector through an exhaust gas conveying pipe, and sends the exhaust gas in the ash bin to the dust collector, and a deflector is also arranged in the exhaust gas collection port. The utility model makes the dust gas in the ash silo directly enter the dust collector for purification through the closed-loop connection established between the ash silo and the dust collector, and does not need to install additional dust removal devices on the upper part of the ash silo to purify the dust, thereby saving production. It reduces the cost, improves the dust removal efficiency of the ash silo, and prevents the secondary dust of the ash silo, which has a good use effect.

Description

A dust removal system of a pneumatic ash conveying device

technical field

The utility model relates to environmental protection equipment, in particular to an ash conveying and dust removal system.

Background technique

In the process of industrial production, a large amount of dust gas containing toxic and harmful substances will be produced. These dust gases must be purified by the dust removal system before being discharged to the atmosphere, and the dust deposited in the dust removal room will be sent to the ash storage through the dust removal and ash delivery system. After being accumulated in the ash storage, it is transported to the dust treatment point by the ash pumping truck for the next step of treatment.

Common dust collectors in the prior art mainly include bag filter and electric dust collector, etc., and ash conveying devices mainly include chain scraper machine, bucket elevator, pneumatic conveying device, etc. Among them, the pneumatic conveying device is the most advanced way of conveying ash, especially the positive pressure dense phase pneumatic conveying device. According to the advanced solid-gas two-phase flow pneumatic conveying principle, the device comprehensively utilizes the static pressure and dynamic pressure of compressed air , Conveying materials with high concentration and high efficiency. The whole system of the positive pressure pneumatic ash conveying device is composed of five parts: gas source part, conveying part, pipeline part, ash storage part and control part, the core of which is the warehouse pump. Every time a pump of dust is transported, it is a working cycle, and each cycle is divided into four stages: feeding, fluidization, conveying, and purging. In the last three stages of each cycle, a certain amount of gas (such as nitrogen, compressed air, etc.) needs to be consumed, and these gases will eventually enter the ash storage together with the dust. In order to prevent secondary dust raising, the ash storage is a sealed container, so the exhaust gas entering the ash storage from the pneumatic ash conveying device must be purified and discharged through a certain device. In the prior art, the tail gas of the ash silo is processed by installing a small dust collector on the top of the ash silo.

In the prior art, the structural characteristics of the dust removal system adopting the positive pressure pneumatic ash conveying method are mainly composed of the following parts as shown in Figure 1: dust removal fan 1, dust removal main pipe, dust collector 2, positive pressure pneumatic ash conveying device 20. Ash silo 8, ash silo tail gas dust collector 14 and corresponding dust removal device 16, control unit 19 and safety valve 15. When working, the dust gas from each dust suction port is evenly distributed into each dust collector 2 through the dust removal main pipe, and purified and separated in the dust collector 2: the clean air is discharged to the atmosphere through the dust removal fan 1; The dust on the filter element is accumulated at the bottom of the dust collector under the action of the dust removal device, and is sent to the ash storehouse 8 through the positive pressure pneumatic ash conveying system device 20, and the dust gas generated by the positive pressure pneumatic conveying is dedusted by the ash storehouse The purification of the dust collector 14 is exhausted to the atmosphere, and the dust accumulated in the dust collector 14 falls into the bottom of the ash storehouse 8 under the action of the dust removal device 16 and the control unit 19 . It can be seen that the ash storage of the existing dust removal system has a relatively complicated tail gas dust removal and discharge system.

The treatment method for the tail gas of the dust storage system in the prior art is shown in Figure 2. For the tail gas generated in the dust storage by pneumatic conveying, it is processed by installing a small dust collector on the top of the dust storage. Take the dedusting system of 3# molten iron pretreatment in Baosteel Co., Ltd. steelmaking plant as an example: molten iron pretreatment is the pre-process of converter smelting, mainly performing operations such as desulfurization and dephosphorization of molten iron. Its dust removal system mainly includes dust removal fan 1, dust collector 2, dust collector ash hopper 3, warehouse pump 4, ash conveying pipeline 7, ash storage 8, etc. The tail gas treatment system of the ash store mainly includes a dust collector 14 for the plastic plate ash store, a pulse cleaning device 16, a pulse control unit 19, and a pulse gas source 18. Nitrogen 5, 6 interacts with dust in the pump chamber 4 to form a solid-gas two-phase flow, and enters the ash storage 8 through the ash delivery pipeline 7. After the gas and dust are initially separated in the ash storage 8 by its own weight, the gas still contains a large amount of dust. After being purified and filtered by the dust collector 14 of the plastic plate ash store, it is discharged to the atmosphere through the exhaust port 17. The dust accumulated on the outer surface of the plastic plate falls into the ash store 8 under the action of the pulse cleaning device 16 , and the action of the pulse cleaning device 16 is realized by the pulse control unit 19 .

In the above dust removal system, the tail gas treatment method of the ash store has the following disadvantages:

1. Large investment: The small dust removal device generally needs to include dust collector, dust removal device, control unit and other components, and the one-time investment cost ranges from 40,000 to 100,000 yuan;

2. High maintenance requirements: common dust removal devices include rapping devices and pulse blowback devices, among which the rapping actuators and backflush control components need frequent maintenance and replacement; and the execution of the dust removal action also involves PLC Control, need to master the corresponding PLC control principle;

3. Frequent faults: Once the filter element is clogged, the tail gas of the ash storage will not be discharged in time, which will cause the back pressure of the ash storage to be too high, resulting in frequent action of the safety valve, resulting in secondary dust, and seriously polluting the environment.

Contents of the invention

The purpose of this utility model is to provide a dust removal system of a pneumatic ash conveying device to solve the problems of complex structure, high investment cost, large maintenance amount and frequent failures in the exhaust gas discharge device of the ash store in the prior art.

Inventive idea: the utility model avoids setting up a dust removal device above the ash storehouse, and adopts a circular dust removal fan-dust collector-positive pressure pneumatic ash conveying device-ash storehouse-dust collector-dust remover fan. Closed-loop design method, by establishing a connection between the ash store and the dust collector, the dust gas conveyed by the positive pressure pneumatic ash conveying device in the ash store is sent to the dust collector, and after being filtered by the dust collector, it is discharged to the atmosphere through the dust removal fan , so that the purification and discharge of the tail gas of the ash store can be solved without any additional dust removal device.

The technical solution of the utility model is: a dust removal system of a pneumatic ash conveying device, comprising: a dust removal fan, a dust collector connected with the dust removal fan, a pneumatic ash conveying device located below the dust collector, and an ash store connected with the pneumatic ash conveying device , the safety valve installed on the ash silo has an exhaust gas collection port on the ash silo, which communicates with the dust collector through an exhaust gas conveying pipe, and sends the exhaust gas in the ash bin to the dust collector. There is also a guide in the exhaust gas collection port. Flow board.

Connect the ash storehouse to the dust collector by using the tail gas collection port and the tail gas conveying pipe, send the dust gas transported by the pneumatic conveying device in the ash store into the dust collector of the dust removal system, and use the dust collector to purify and discharge the tail gas of the ash storehouse. Thereby avoiding another dust removal device on the ash storehouse for dust removal.

Preferably, a cut-off valve is provided on the exhaust gas delivery pipe. When the ash in the ash silo accumulates to a certain level, it needs to be taken out by the ash pumping truck. In order to ensure the normal operation of the ash truck when pumping ash, and prevent the dust removal fan from forming a negative pressure in the ash silo, which hinders the normal ash pumping, the exhaust gas There is a pneumatic shut-off valve (normally open) on the delivery pipeline.

Preferably, the exhaust gas collection port is connected by a circle. Its shape is trumpet-shaped, the wide mouth is square, connected with the ash tank, and the narrow mouth is round, connected with one end of the exhaust gas delivery pipe. The other end of the tail gas delivery pipe is connected to the dust collector, thereby forming a closed-loop connection between the dust collector and the ash store.

Preferably, the inclination angle α of the deflector is 70-50 degrees. In order to minimize the dust content of the exhaust gas and prevent the dust in the ash storage from being sucked into the exhaust gas collection port, a deflector and its positioning parts are designed under the exhaust gas collection port, and the positioning parts are welded on the inner wall of the top cover of the ash storage. The deflector is mounted on the positioning piece. The number, size and inclination angle of the deflectors can be determined through calculation and empirical values in combination with factors such as the size of the ash store, the specific gravity of the dust, and the working pressure of the pneumatic ash conveying system.

Compared with the prior art, the present invention has the following beneficial effects:

1) The utility model does not require additional dust removal devices on the ash storehouse, thereby reducing the dust removal cost of the ash storehouse from 30,000 to 100,000 yuan in the prior art to several thousand yuan, saving production costs to a relatively high degree.

2) The utility model improves the dust removal efficiency of the ash silo, eliminates the secondary dust raising of the ash silo, and has a good use effect.

3) The utility model also has the advantages of strong adaptability, reliable operation, and maintenance-free, which can save a lot of spare parts material costs and maintenance costs.

Description of drawings

Fig. 1 is a schematic diagram of a pneumatic dust removal and ash conveying device in the prior art.

Fig. 2 is a schematic diagram of the working principle of the pneumatic dust removal and ash conveying device in the prior art.

Fig. 3 is a schematic diagram of an embodiment of the present invention.

Fig. 4 is a schematic diagram of the working principle of an embodiment of the present invention.

In the figure, 1 is the dust removal fan, 2 is the dust collector, 3 is the ash hopper of the dust collector, 4 is the warehouse pump, 5 is the nitrogen gas conveyed, 6 is the fluidized nitrogen gas, 7 is the ash conveying pipe, 8 is the ash storage, and 9 is the Ash inlet pipe, 10 is deflector and positioning piece, 11 is square connection, 12 is tail gas conveying pipe, 13 is pneumatic cut-off valve, 14 is dust collector of ash storehouse, 15 is safety valve, 16 is pulse cleaning device, 17 18 is a pulse gas source, 19 is a pulse control unit, 20 is a positive pressure pneumatic ash conveying device, and 21 is a dust conveying control switch.

Detailed ways

In one embodiment of the present utility model, as shown in Figure 3:

A dust removal system of a pneumatic ash conveying device, comprising: a dust removal fan 1, a dust collector 2 connected to the dust removal fan 1, a positive pressure pneumatic ash conveying device 20, an ash storehouse 8, an explosion-proof safety valve 15, a deflector and a positioning member 10, Fangyuan connection 11, exhaust gas delivery pipe 12, pneumatic shut-off valve 13. The dust collector 2 connected to the dust removal fan 1 is connected to one end of the positive pressure pneumatic ash conveying device 20, and the square circle connection 11 is arranged above the ash storehouse 8, and it communicates with the dust collector 2 through an exhaust gas conveying pipe 12, so as to discharge the dust The tail gas in the storehouse 8 is sent into the dust collector. The deflector is installed on the positioning part, and the deflector and the positioning part 10 are fixed on the inner wall of the ash storehouse 8 top cover. The pneumatic shut-off valve 13 is arranged on one end of the exhaust gas conveying pipe 12 close to the square-circle joint 11 . The explosion-proof safety valve 15 is arranged on the external top cover of the ash storehouse 8 .

The ash storehouse 8 is connected with the dust collector 2 through the radius connection 11 and the tail gas conveying pipe 12, so that the dust gas generated by the pneumatic conveying device 20 in the ash storehouse 8 is sent into the dust collector 2 of the dust removal system, and the dust collector 2 is used to The tail gas in the ash silo 8 is purified and discharged, thereby eliminating the need for an additional ash silo dedusting device.

In order to ensure the safe operation of the ash silo 8 and prevent the ash silo 8 from exploding due to excessive positive pressure or being sucked flat due to excessive negative pressure, according to the working pressure of the ash conveying gas source and the working pressure of the dust removal fan, the A corresponding explosion-proof safety valve 15 integrating positive pressure explosion-proof and negative-pressure explosion-proof is provided, the positive pressure explosion-proof pressure is 12000pa, and the negative pressure explosion-proof pressure is 800pa.

The square circle connecting 11 that is arranged on the ash storehouse 8 tops is trumpet shape, and wide mouth is square, is connected with ash storehouse 8, and narrow mouth is circular, is connected with one end of tail gas conveying pipe 12. The other end of the tail gas conveying pipe 12 is connected with the dust collector, thereby forming a closed-loop connection between the dust collector 2 and the ash storehouse 8 .

The below of square circle connection 11 is provided with three deflectors and its positioning parts 10 that are changed from long to short, can minimize the dust content of tail gas, prevents the dust in ash storehouse 8 from inhaling square circle connection 11. The positioning piece is welded on the top cover inner wall of the ash storehouse 8, and the deflector is installed on the positioning piece, and its inclination angle α is 70 degrees.

When the ash in the ash silo 8 has accumulated to a certain extent, it needs to be drawn out by the ash pumping car, and the pneumatic shut-off valve 13 is arranged on the tail gas conveying pipe 12 to ensure the normal operation of the ash truck when the ash is pumped, and prevent the dust removal fan 1 from being damaged in the ash silo. Negative pressure is formed in 8, which hinders the normal progress of ash extraction, and the state of the pneumatic shut-off valve 13 is normally open.

The working principle of the utility model is shown in Figure 4: the ash conveying control switch 21 of the positive pressure pneumatic ash conveying device is installed in the control unit of the positive pressure pneumatic ash conveying system, and has the function of simultaneously controlling the start and the start of the pneumatic ash conveying device 20 The dual functions of stopping and opening and closing of the pneumatic shut-off valve 13: when the ash storage 8 needs to pump ash, by opening the ash transport control switch 21, the positive pressure pneumatic ash transport device 20 is temporarily closed, and the shut-off valve 13 is closed at the same time, thereby ensuring The ash truck can normally extract ash; when the ash storage 8 finishes, close the ash conveying control switch 21, start the pneumatic ash conveying device 20, open the shut-off valve 13 simultaneously, and carry out the ash conveying operation again. At this time, the tail gas treatment process in the ash conveying system is shown by the arrows in Figure 4: the nitrogen 5 and 6 used for fluidization and conveying interact with the dust in the bin pump 4 to form a solid-gas two-phase flow, and pass through the ash conveying pipeline 7. Enter the ash chamber 8 from the ash inlet pipe 9, and the dust gas is preliminarily separated from the gas and dust under the action of the deflector 10 and its own weight. After that, the gas still containing a certain amount of dust passes through the tail gas delivery pipe 12 from the square circle connection 11, Enter the ash hopper 3 of the dust collector 2, and then be filtered and purified by the dust collector 2, and then discharged to the atmosphere from the dust removal fan 1.

Claims (4)

1. the dust pelletizing system of a pneumatic ash conveying plant, comprise: dedusting fan, with dedusting fan bonded assembly dust exhaustor, be positioned at the pneumatic ash conveying plant of dust exhaustor below, the grey storehouse that links to each other with pneumatic ash conveying plant, be located at the safety valve on the grey storehouse, it is characterized in that grey storehouse is provided with an exhaust collection mouth, it is connected with dust exhaustor by an exhaust pipe, tail gas in the grey storehouse is sent into dust exhaustor, also be provided with deflecting plate in the exhaust collection mouth.

2. the dust pelletizing system of pneumatic ash conveying plant as claimed in claim 1 is characterized in that, exhaust pipe is provided with a shutoff valve.

3. the dust pelletizing system of pneumatic ash conveying plant as claimed in claim 1 or 2 is characterized in that, the exhaust collection mouth is that a circumference connects.

4. the dust pelletizing system of pneumatic ash conveying plant as claimed in claim 3 is characterized in that, the inclined angle alpha of described deflecting plate is 70～50 degree.

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