CN103333983A - Converter primary flue gas dry dedusting and cinder pneumatic transmission system - Google Patents

Abstract

The invention relates to a coarse ash pneumatic conveying system for primary flue gas dry dedusting of a converter, which includes an evaporative cooling tower (1), an ash discharge pipe (4), a warehouse pump (10), a pneumatic conveying pipe (17) and a coarse ash that are connected in sequence. Ash bin (18); rapping device (2) and material level gauge (3) are installed in the evaporative cooling tower (1); the pneumatic conveying pipe (17) is connected to the air storage tank (14), and the air storage tank (14) The inlet of the first nitrogen pipe (13) is connected to the first nitrogen pipe (13), and the inlet of the first nitrogen pipe (13) is connected to the nitrogen main pipe; the bin pump (10) and the coarse ash bin (18) are connected through the pneumatic conveying pipe (17). The present invention can use ordinary ash trucks to transport ash, which greatly reduces investment and saves costs. At the same time, the invention reduces the number of equipment and equipment maintenance, and solves the problem of limited height of the evaporative cooling tower in the transformation of dry dedusting. It is especially suitable for the project of converter primary flue gas wet dedusting to dry dedusting, and has broad application prospects.

Description

A Pneumatic Conveying System for Coarse Ash Pneumatic Conveying System for Primary Flue Gas Dry Dedusting of Converter

technical field

The invention relates to the field of environmental protection equipment, in particular to a coarse ash pneumatic conveying system for primary flue gas dry dedusting of a converter.

Background technique

With the continuous strengthening of environmental protection awareness, most of the primary flue gas of newly built and rebuilt converters adopts dry dust removal. The coarse ash collected by the banana bend under the evaporative cooling tower is sent to the coarse ash bin in the main workshop of the converter under the action of gravity through the built-in chain conveyor, pneumatic flap valve and pneumatic double flap valve, and the coarse ash is directly discharged by the vacuum suction tanker Comprehensive utilization of Sinotrans.

The main problems of the existing converter primary flue gas dry dedusting coarse ash conveying system are as follows: first, the built-in chain conveyor has a high failure rate and often gets stuck, which seriously affects the normal production of the converter; second, the coarse ash bin is located in the main workshop of the converter In the interior, it is often restricted by the layout conditions of the steelmaking process. It is necessary to consider the ash transportation channel for cars to enter and exit, which takes up a lot of indoor space; the third is that the price of each vacuum suction tanker is about 1 million yuan, and the investment is relatively high.

Contents of the invention

The technical problem to be solved by the present invention is to provide a coarse ash pneumatic conveying system for primary flue gas dry dedusting of the converter in view of the above-mentioned defects of the prior art.

The technical solution adopted by the present invention to solve the technical problem is: to construct a coarse ash pneumatic conveying system for primary flue gas dry dedusting of the converter, including an evaporative cooling tower, ash unloading pipe, warehouse pump, pneumatic conveying pipe and coarse ash which are connected in sequence warehouse;

The lower cone bucket at the bottom of the evaporative cooling tower is used to catch the coarse ash in the raw gas. The evaporative cooling tower is equipped with a vibrating device and a level gauge; the warehouse pump is installed below the evaporative cooling tower. The ash unloading port of the lower cone bucket of the evaporative cooling tower is connected to the inlet of the warehouse pump through the ash unloading pipe, and the ash unloading pipe is provided with a pneumatic slide valve and a first pneumatic double gate valve; the top of the warehouse pump A first vacuum pressure release valve is provided;

The pneumatic conveying pipe is connected to the gas storage tank, the inlet of the gas storage tank is connected to the first nitrogen pipe, and the inlet of the first nitrogen pipe is connected to the nitrogen main pipe; the bin pump and the coarse ash bin are connected through the pneumatic conveying pipe The pneumatic conveying pipe is provided with a second pneumatic double gate valve, and the bottom of the warehouse pump is provided with a first fluidization device;

The nitrogen pipe at the outlet of the gas storage tank is divided into two paths, one path is connected with the first fluidization device, and the other path is connected with the pneumatic conveying pipe, and a pneumatic ball valve is arranged between the gas storage tank and the warehouse pump;

The top of the coarse ash bin is provided with a bag filter and a second vacuum pressure release valve, and the lower cone of the coarse ash bin is provided with a second fluidization device, and the ash discharge port of the lower cone at the bottom of the coarse ash bin and The inlet of the second manual flapper valve is connected, and the outlet of the second manual flapper valve is connected with the inlet of the dust humidification mixer; the outlet of the dust humidification mixer is connected with the inlet of the canvas hose through the ash discharge pipe;

The nitrogen main pipe is also connected to the inlet of the second nitrogen pipe, and the outlet of the second nitrogen pipe is divided into two paths, one path is connected to the second fluidization device, and the other path is connected to the bag filter on the top of the warehouse;

A pressure regulating valve and an electromagnetic valve are arranged between the second nitrogen pipe and the second fluidization device.

In the coarse ash pneumatic conveying system for converter primary flue gas dry dust removal according to the present invention, the first emergency ash discharge pipe is provided on the lower cone bucket of the evaporative cooling tower, and the first accident ash discharge pipe is provided with a first emergency ash discharge pipe. Manual flapper valve.

In the coarse ash pneumatic conveying system for converter primary flue gas dry dedusting described in the present invention, a connecting pipe is provided between the ash unloading pipe and the first accident ash unloading pipe.

In the coarse ash pneumatic conveying system for primary dry dust removal of converter flue gas according to the present invention, the second emergency ash discharge pipe is provided on the lower cone bucket of the coarse ash bin, and the second accident ash discharge pipe is provided with a second emergency ash discharge pipe. Three manual flapper valves.

In the coarse ash pneumatic conveying system for converter primary flue gas dry dedusting described in the present invention, the evaporative cooling tower is provided with manholes.

In the coarse ash pneumatic conveying system for converter primary flue gas dry dedusting described in the present invention, a drain pipe is provided at the bottom of the warehouse pump.

Implementing the converter primary flue gas dry dedusting coarse ash pneumatic conveying system of the present invention has the following beneficial effects:

1. Reduce the number of equipment and equipment maintenance. The removable set of banana bends and the built-in chain conveyor solve the problem of dust stuck in the built-in chain conveyor, reduce the failure rate of equipment, and ensure the normal production of the converter.

2. The coarse ash bin can be placed inside or outside the main converter building. Ash storage and transportation are not limited by site and distance.

3. After the dust humidification mixer is used in the present invention, the ash can be transported by an ordinary ash truck, which greatly reduces investment and saves costs.

4. The invention solves the problem that the height of the evaporative cooling tower is limited during the transformation of dry dust removal, and is especially suitable for the project of converter primary flue gas wet dust removal to dry dust removal project, and has broad application prospects.

Description of drawings

The present invention will be further described below in conjunction with accompanying drawing and embodiment, in the accompanying drawing:

Fig. 1 is a structural schematic diagram of the coarse ash pneumatic conveying system for converter primary flue gas dry dedusting of the present invention.

Detailed ways

In order to have a clearer understanding of the technical features, purposes and effects of the present invention, the specific implementation manners of the present invention will now be described in detail with reference to the accompanying drawings.

As shown in FIG. 1 , the coarse ash pneumatic conveying system for converter primary flue gas dry dedusting of the present invention includes an evaporative cooling tower 1 , an ash discharge pipe 4 , a bin pump 10 , a pneumatic conveying pipe 17 and a coarse ash bin 18 connected in sequence.

The lower cone bucket of the evaporative cooling tower 1 is used to capture the coarse ash in the raw gas, and the evaporative cooling tower 1 is equipped with a material level gauge 3 and a rapping device 2 . The amount of coarse ash in the evaporative cooling tower 1 can be detected by the level gauge 3, and the rapping device 2 can ensure that the coarse ash can smoothly fall into the ash discharge pipe 4 to prevent blockage. The warehouse pump 10 is installed below the evaporative cooling tower 1, and the ash discharge port of the lower cone of the evaporative cooling tower 1 is connected to the inlet of the warehouse pump 10 through the ash discharge pipe 4. The ash discharge pipe 4 is provided with a pneumatic slide valve 5 and a second A pneumatic double gate valve 6. When the pneumatic flapper valve 5 and the first pneumatic double gate valve 6 are opened, the coarse ash inside the evaporative cooling tower 1 falls into the bin pump 10 through the ash discharge pipe 4 . The top of the warehouse pump 10 is provided with a first vacuum pressure release valve 12 to prevent the internal pressure of the warehouse pump 10 from being too high.

The pneumatic conveying pipe 17 is connected with the gas storage tank 14, the inlet of the gas storage tank 14 is connected with the first nitrogen pipe 13, and the inlet of the first nitrogen pipe 13 is connected with the nitrogen main pipe. The bin pump 10 and the coarse ash bin 18 are connected through a pneumatic conveying pipe 17, on which a second pneumatic double gate valve 16 is arranged, and a first fluidization device is arranged at the bottom of the bin pump 10.

The nitrogen pipe at the outlet of the gas storage tank 14 is divided into two paths, one is connected with the first fluidization device, and the other is connected with the pneumatic conveying pipe 17, and a pneumatic ball valve 15 is arranged between the gas storage tank 14 and the warehouse pump 10.

The top of the coarse ash bin 18 is provided with a bin top bag filter 19 and a second vacuum pressure release valve 20 . The top bag filter 19 is used to collect the dust on the top of the coarse ash bin 18 . The second vacuum pressure relief valve 20 is used to prevent excessive pressure inside the coarse ash bin 18 . A second fluidization device 30 is provided in the lower cone of the coarse ash bin 18, the ash discharge port of the lower cone of the coarse ash bin 18 is connected to the inlet of the second manual flapper valve 21, and the outlet of the second manual flapper valve 21 is connected to the The inlet of the dust humidifying mixer 22 is connected, and the outlet of the dust humidifying mixer 22 is connected with the inlet of the canvas hose 24 through the ash discharge pipe 23 .

The nitrogen main pipe is also connected with the second nitrogen pipe 27 inlet, and the second nitrogen pipe 27 outlet is divided into two paths, one path is connected with the second fluidization device 30, and the other path is connected with the bag filter 19 on the warehouse top. A pressure regulating valve 28 and a solenoid valve 29 are provided between the second nitrogen pipe 27 and the second fluidization device 30 .

The process flow of the coarse ash pneumatic conveying system for primary flue gas dry dedusting of the intermediate converter of the present invention is as follows:

Evaporative cooling tower 1 lower cone bucket ash discharge port → ash discharge pipe 4 → pneumatic slide valve 5 → first pneumatic double gate valve 6 → warehouse pump 10 → second pneumatic double gate valve 16 → pneumatic conveying pipe 17 → coarse Ash bin 18→second manual flapper valve 21→dust humidification mixer 22→ash discharge pipe 23→canvas hose 24.

When the dust-laden raw gas passes through the lower cone of the evaporative cooling tower, due to the change of the flow direction by more than 90°, under the action of gravity and centrifugal force, 25% to 35% of the coarse particle dust, generally 30%, is captured at the lower cone collection; the temperature of coarse particle dust is 200-300°C, generally 250°C; the bulk density of coarse particle dust is 1.8-2.6t/m ³ ; the moisture content of coarse particle dust is 3%-5%.

When the material level gauge 3 detects that the coarse ash in the lower cone bucket of the evaporative cooling tower 1 reaches the upper limit, it sends out a signal, and starts to unload the ash to the warehouse pump 10, and the rapping device 2 starts to work at the same time. Coarse ash enters the warehouse pump 10 through the ash discharge port of the lower cone bucket of the evaporative cooling tower 1, the ash discharge pipe 4, the pneumatic slide valve 5 and the first pneumatic double gate valve 6. After the storage pump 10 is full, it passes through the first fluidization device After fluidization, it is sent to the coarse ash bin 18 through the pneumatic conveying pipe 17 . A level gauge may also be provided in the warehouse pump 10 to detect the amount of coarse ash in the warehouse pump 10 through the material level gauge. When the solenoid valve 29 is opened, the second fluidizing device 30 sprays low-pressure nitrogen gas, which can reduce the temperature of the coarse ash in the coarse ash bin 18, and also fluidize the coarse ash to facilitate ash unloading. The coarse ash collected by the bag filter 19 on the top of the warehouse is transported to the bottom of the coarse ash bin 18 through the second nitrogen pipe 27, so as to ensure that the coarse ash in the coarse ash bin 18 can be quickly and fully unloaded and the residue is reduced. The feed rate of nitrogen can be adjusted by the pressure regulating valve 28 . Common ash trucks are used for ash unloading, and the coarse ash is added to the ash truck through the ash discharge pipe 23 and canvas hose 24 after being humidified by the dust humidification mixer 22 .

When the material level gauge 3 in the evaporative cooling tower 1 detects that the coarse ash in the lower cone bucket of the evaporative cooling tower 1 is unloaded to the lower limit, it sends out a signal, stops discharging ash to the bin pump 10, and simultaneously the vibrating device 2 stops working. The ash seal in the lower cone of the evaporative cooling tower can prevent gas from overflowing, and the ash seal height is 800-1000mm.

Further, the lower cone bucket of the evaporative cooling tower 1 is provided with a first emergency ash discharge pipe 7 , and a first manual slide valve 9 is provided on the first emergency ash discharge pipe 7 . When the warehouse pump 10 is overhauled, the coarse ash is discharged through the emergency ash discharge port of the lower cone bucket of the evaporative cooling tower 1, the first accident ash discharge pipe 7 and the first manual slide valve 9. A connecting pipe 8 is arranged between the ash unloading pipe 4 and the first accident ash unloading pipe 7, which is mainly used to get rid of the accidental accumulated water in the lower cone bucket of the evaporative cooling tower 1. A drain pipe 11 may also be provided at the bottom of the warehouse pump 10 to discharge accumulated water in the warehouse pump 10 .

Further, a second emergency ash discharge pipe 25 is provided on the lower cone of the coarse ash bin 18, and a third manual slide valve 26 is provided on the second accident ash discharge pipe 25. When the coarse ash bin 18 is overhauled, the coarse ash is discharged through the cone bucket accident ash discharge port of the coarse ash bin 18, the second accident ash discharge pipe 25 and the third manual slide valve 26.

Further, manholes are provided on the evaporative cooling tower 1 for easy maintenance.

Further, the material of the warehouse pump 10 is 16MnR or Q235B or ductile iron or stainless steel. The capacity of the warehouse pump 10: 1.0～10m ³ ; the quantity of the warehouse pump 10 is ≥1, and multiple combinations can be used. The pneumatic conveying pipe 17 is made of manganese-containing seamless steel pipe, and the elbow and tee are lined with wear-resistant ceramic materials. The bending radius of the pipe is ≥10 times the diameter of the pipe, and the pipe has an anti-blocking function.

The warehouse pump 10 adopts the method of discontinuous conveying, and every time the coarse ash is conveyed, it is a cycle process, and each cycle is divided into 4 steps:

1. Feed material: the pneumatic flapper valve 5 and the first pneumatic double gate valve 6 are in the open state, the pneumatic ball valve 15 and the second pneumatic double gate valve 16 are closed, the warehouse pump 10 is connected with the lower cone bucket of the evaporative cooling tower 1, The rapping device 2 works, and the coarse ash enters the warehouse pump 10 under the action of gravity. When the material level gauge 3 of the warehouse pump 10 detects that the material is full, it sends a signal and is controlled by the PLC program to automatically close the first pneumatic double ram. Valve 6, the feeding process ends, and the rapping device 2 stops working.

2. Fluidization: The pneumatic ball valve 15 is opened, nitrogen enters the first fluidization device in the warehouse pump 10 from the gas storage tank 14, the coarse ash in the warehouse pump 10 is fully fluidized, and the pressure continues to rise. When the pressure rises to the set working When the pressure is high, the second pneumatic double gate valve 16 at the discharge port on the side of the warehouse pump 10 is automatically opened through the PLC program control, and the fluidization process is completed and enters the conveying process.

3. Conveying: After the second pneumatic double gate valve 16 is opened, the uniformly fluidized gas-ash mixture is sent to the coarse ash bin 18 through the pneumatic conveying pipe 17, and the pressure in the bin pump 10 is kept stable at this time. After the air-ash mixture in the warehouse pump 10 is conveyed, the resistance of the pneumatic conveying pipe 17 decreases, and the pressure of the pneumatic conveying pipe 17 begins to decrease. When it drops to the set lower limit pressure, the conveying process ends and enters the purging process. At this moment, the pneumatic ball valve 15 and the second pneumatic double gate valve 16 are still kept in the open state.

4. Purging: Nitrogen continues to purge the warehouse pump 10 and the pneumatic conveying pipe 17. At this time, there is no fly ash in the warehouse pump 10, and the air-ash mixture in the pneumatic conveying pipe 17 gradually decreases, and finally almost all of them are nitrogen, and the system resistance continues to decrease After stabilizing for a period of time, the purging process ends, close the pneumatic ball valve 15 and the second pneumatic double gate valve 16, then open the first pneumatic double gate valve 6, and the warehouse pump 10 returns to the feeding state. At this point, a conveying cycle including steps ends, and the next cycle starts again.

The converter in the converter primary flue gas dry dedusting coarse ash pneumatic conveying system of the present invention is defined as: a decarburization converter or a dephosphorization converter or a lava homogenizing furnace or a stainless steel converter. The pneumatic conveying system of the present invention is suitable for conveying coarse ash of primary flue gas dry dust removal of 80t-300t converters. Its conveying distance is about 300m, and its climbing height is about 30m. The conveying medium adopts low-pressure nitrogen, and the nitrogen pressure is ≥0.6MPa.

Embodiments of the present invention have been described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific implementations, and the above-mentioned specific implementations are only illustrative, rather than restrictive, and those of ordinary skill in the art will Under the enlightenment of the present invention, many forms can also be made without departing from the gist of the present invention and the protection scope of the claims, and these all belong to the protection of the present invention.

Claims (6)

1. A coarse ash pneumatic conveying system for converter primary flue gas dry dedusting, characterized in that it includes sequentially connected evaporative cooling tower (1), ash discharge pipe (4), warehouse pump (10), pneumatic conveying pipe (17 ) and coarse ash bin (18); The lower cone bucket at the bottom of the evaporative cooling tower (1) is used to capture the coarse ash in the raw gas, and the evaporative cooling tower (1) is equipped with a vibrating device (2) and a level gauge (3); The pump (10) is installed below the evaporative cooling tower (1), and the ash discharge port of the lower cone of the evaporative cooling tower (1) is connected to the inlet of the bin pump (10) through the ash discharge pipe (4) , the ash discharge pipe (4) is provided with a pneumatic gate valve (5) and a first pneumatic double gate valve (6); the top of the warehouse pump (10) is provided with a first vacuum pressure release valve (12) ; The pneumatic conveying pipe (17) is connected to the gas storage tank (14), the inlet of the gas storage tank (14) is connected to the first nitrogen pipe (13), and the inlet of the first nitrogen pipe (13) is connected to the nitrogen gas The main pipe is connected; the bin pump (10) and the coarse ash bin (18) are connected through a pneumatic conveying pipe (17), and a second pneumatic double gate valve (16) is provided on the pneumatic conveying pipe (17). There is a first fluidization device at the bottom of the warehouse pump (10); The nitrogen pipe at the outlet of the gas storage tank (14) is divided into two paths, one path is connected to the first fluidization device, and the other path is connected to the pneumatic conveying pipe (17). The gas storage tank (14) and the warehouse A pneumatic ball valve (15) is provided between the pumps (10); The top of the coarse ash bin (18) is equipped with a top bag filter (19) and a second vacuum pressure release valve (20), and the lower cone of the coarse ash bin (18) is equipped with a second fluidization device ( 30), the ash discharge port of the lower cone bucket at the bottom of the coarse ash bin (18) is connected to the inlet of the second manual flapper valve (21), and the outlet of the second manual flapper valve (21) is connected to the dust humidification The inlet of the mixer (22) is connected; the outlet of the dust humidification mixer (22) is connected with the inlet of the canvas hose (24) through the ash discharge pipe (23); The nitrogen main pipe is also connected to the inlet of the second nitrogen pipe (27), and the outlet of the second nitrogen pipe (27) is divided into two paths, one path is connected to the second fluidization device (30), and the other path is connected to the top bag dust collector Device (19) is connected; A pressure regulating valve (28) and a solenoid valve (29) are provided between the second nitrogen pipe (27) and the second fluidization device (30). 2. The coarse ash pneumatic conveying system according to claim 1, characterized in that, the lower cone of the evaporative cooling tower (1) is provided with a first emergency ash unloading pipe (7), The first emergency ash unloading pipe (7) is provided with a first manual flapper valve (9). 3. The coarse ash pneumatic conveying system according to claim 2, characterized in that a connecting pipe is provided between the ash discharge pipe (4) and the first accident ash discharge pipe (7) (8). 4. The coarse ash pneumatic conveying system according to claim 1, characterized in that the second emergency ash unloading pipe (25) is provided on the lower cone of the coarse ash bin (18), The second emergency ash discharge pipe (25) is provided with a third manual slide valve (26). 5. The pneumatic conveying system for primary dry dust removal of converter primary flue gas and coarse ash according to claim 1, characterized in that, the evaporative cooling tower (1) is provided with manholes. 6. The coarse ash pneumatic conveying system according to claim 1, characterized in that a drain pipe (11) is provided at the bottom of the warehouse pump (10).

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