System for unpowered separation of unfired coal particles from coal cinder of CFB (circulating fluidized bed) boiler

Abstract

The utility model provides a CFB (circulating fluidized bed) boiler coal cinder unpowered unfired coal particle separation system, which relates to the technical field of unpowered unfired coal particle separation, and comprises a cinder bin, a bucket elevator, a fine ash separation part, a secondary separation part and a tertiary separation part, the third-time separation part is used for carrying out third-time separation on the coal slag which passes through the second-time separation part but is not conveyed into the slag bin, the third-time separation part is used for separating gangue particles with relatively large volume and density and conveying the gangue particles into the slag bin, and the remaining coal slag / raw coal with high calorific value is conveyed into the boiler; the device can separate out unburnt raw coal particles in slag and return the unburnt raw coal particles to the furnace for re-burning, so that the problems that the raw coal is mixed with gangue, the crushing does not reach the standard and the coal particles are too large, and a special design structure for feeding coal falling, fluidization, material returning circulation and slag discharging in the hearth is adopted are reduced; and therefore, the waste of raw coal energy sources is reduced, and the waste of the raw coal energy sources is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of unpowered separation of unburned coal particles, in particular to an unpowered separation system of unburned coal particles of a CFB boiler coal ash. Background Art

[0002] The slag of a circulating fluidized bed boiler is usually caused by the raw coal being mixed with gangue, the crushing not meeting the standards, the coal particles being too large, and the special design structure of the feeding, fluidization, return circulation and slag discharge in the furnace. As a result, some of the raw coal particles are not completely burned or even completely large. The combustion is terminated when the boiler is running and the slag is discharged from the furnace along with the coal. This causes a large amount of raw coal energy to be wasted and the cost of boiler steam production to be increased. Utility Model Content

[0003] The utility model aims to provide a CFB boiler ash unpowered separation system for unburned coal particles, aiming to solve the problems mentioned in the above background technology.

[0004] To achieve the above purpose, the utility model adopts the following technical solution: the CFB boiler slag unpowered separation system for unburned coal particles includes a slag bin, a bucket elevator, and also includes:

[0005] A fine ash separation unit, which is used to separate fine ash-like coal slag particles from coal slag and transport the fine ash-like coal slag particles to a slag bin;

[0006] A secondary separation unit, which can perform secondary separation on the coal slag that has not been transported to the slag bin, and separate the gangue particles in the coal slag and transport them to the slag bin;

[0007] The tertiary separation section is used to perform a tertiary separation on the coal slag that has passed through the secondary separation section but has not been transported to the slag bin. The tertiary separation section is used to separate the gangue particles and transport them to the slag bin, and the remaining coal slag / raw coal with high calorific value is transported to the boiler.

[0008] Preferably, the fine ash separation part includes a fine ash separation pipe, the bucket elevator has a slag outlet, the fine ash separation pipe is installed at the slag outlet of the bucket elevator, the fine ash separation pipe is arranged obliquely downward, a fine ash sieve plate is arranged at the inner bottom of the fine ash separation pipe, the coal ash passing through the slag outlet enters the upper surface of the fine ash sieve plate, a fine ash collecting plate is arranged on the lower surface of the fine ash separation pipe, the outer surface of the lower end of the fine ash separation pipe is through-connected with a fine ash collecting bin, the fine ash in the coal ash passes through the fine ash sieve plate and enters the fine ash collecting plate, and slides into the fine ash collecting bin under the action of gravity, a fine ash slag dropping pipe is arranged at the lower end of the fine ash collecting bin, a first gravity-type flap air lock is arranged between the fine ash collecting bin and the fine ash slag dropping pipe, and the lower end of the fine ash slag dropping pipe is through-connected with the slag bin.

[0009] Preferably, the secondary separation part includes a gravity separation ejection bin which is connected to the fine ash separation pipe, a first separation baffle is arranged inside the gravity separation ejection bin, a coarse slag collecting bucket is arranged at the lower end of the gravity separation ejection bin, a coarse slag dropping pipe is connected to the lower end of the coarse slag collecting bucket, a second gravity flap air lock is arranged between the coarse slag collecting bucket and the coarse slag dropping pipe, and the lower end of the coarse slag dropping pipe is connected to the slag bin.

[0010] Preferably, the tertiary separation part includes a negative pressure separation bin that is through-connected with the gravity separation ejection bin, and also includes a negative pressure pipe, the negative pressure pipe is through-connected with the negative pressure separation bin, an air inlet is provided on one side of the negative pressure separation bin, and the coal slag that has not entered the coarse slag collecting bucket enters the negative pressure separation bin after passing through the first separation baffle, the lower end of the negative pressure separation bin is provided with a first discharge port and a second discharge port, a second separation baffle is provided inside the negative pressure separation bin, the second separation baffle is used to transport the coal slag to the first discharge port and the second discharge port respectively, a first discharge pipe is provided at the lower end of the first discharge port, a third gravity flap air lock is provided between the first discharge port and the first discharge pipe, the lower end of the first discharge pipe is through-connected with the feed port of the coal feeder, a second discharge pipe is provided at the lower end of the second discharge port, a fourth gravity flap air lock is provided at the lower end of the second discharge port and the second discharge pipe, and the lower end of the second discharge pipe is through-connected with the slag bin.

[0011] Preferably, a blocking plate is provided at the lower end of the gravity separation ejection bin.

[0012] The beneficial effects of the utility model are:

[0013] The device can separate the unburned raw coal particles in the slag and return them to the furnace for re-combustion, thereby reducing the situation where the slag contains some unburned or even completely large raw coal particles due to the raw coal being mixed with gangue, substandard crushing, excessively large coal particles, and the special design structure of feeding, fluidization, return circulation and slag discharge in the furnace, thereby reducing the waste of raw coal energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of a specific embodiment of the utility model.

[0015] Figure 2 yes Figure 1 A partial enlarged view of point A in the middle.

[0016] In the figure: 1. slag bin; 2. bucket elevator; 3. fine ash separation pipe; 4. fine ash sieve plate; 5. fine ash collecting plate; 6. fine ash collecting bin; 7. fine ash dropping pipe; 8. first gravity flap air lock; 9. gravity separation ejection bin; 10. first separation baffle; 11. coarse slag collection bucket; 12. coarse slag dropping pipe; 13. second gravity flap air lock; 14. negative pressure separation bin; 15. negative pressure pipe; 16. air inlet; 17. first discharge port; 18. second discharge port; 19. second separation baffle; 20. first discharge pipe; 21. second discharge pipe; 22. third gravity flap air lock; 23. fourth gravity flap air lock; 24. blocking plate; 25. coal feeder. DETAILED DESCRIPTION

[0017] The specific implementation of the utility model is further described below in conjunction with the accompanying drawings.

[0018] like Figure 1-2 As shown, a CFB boiler slag unpowered separation system for unburned coal particles includes a slag bin 1, a bucket elevator 2, and also includes:

[0019] The fine ash separation section is used to separate the fine ash-like coal slag particles from the coal slag and transport the fine ash-like coal slag particles to the slag bin 1; the fine ash-like coal slag particles can be regarded as round, and the fine ash separation section mainly separates the fine ash-like coal slag particles with a diameter less than 3 mm from the coal slag. The fine ash-like coal slag particles separated in this part have no value for reuse and can be directly transported to the slag bin 1.

[0020] Specifically, the fine ash separation part includes a fine ash separation pipe 3, the bucket elevator 2 has a slag outlet, the fine ash separation pipe 3 is installed at the slag outlet of the bucket elevator 2, the fine ash separation pipe 3 is arranged obliquely downward, a fine ash sieve plate 4 is arranged at the inner bottom of the fine ash separation pipe 3, the coal slag passing through the slag outlet enters the upper surface of the fine ash sieve plate 4, a fine ash collecting plate 5 is arranged on the lower surface of the fine ash separation pipe 3, and a fine ash collecting bin 6 is connected to the outer surface of the lower end of the fine ash separation pipe 3, the fine ash in the coal slag passes through the fine ash sieve plate 4 and enters the fine ash collecting plate 5, and slides down into the fine ash collecting bin 6 under the action of gravity, a fine ash slag dropping pipe 7 is arranged at the lower end of the fine ash collecting bin 6, and a first gravity feeder is arranged between the fine ash collecting bin 6 and the fine ash slag dropping pipe 7 The lower end of the fine ash slag dropping pipe 7 is connected with the slag bin 1, and the coal ash discharged from the boiler combustion is transported to a high place through the bucket elevator 2, and then the coal ash enters the fine ash separation pipe 3. Under the action of gravitational potential energy, the coal ash rolls downward along the inclined fine ash separation pipe 3, and some fine ash coal ash particles with a diameter less than 3 mm pass through the fine ash sieve plate 4 and fall to the bottom of the fine ash sieve plate 4, some fine ash particles fall onto the fine ash collecting plate 5, and slide into the fine ash collecting bin 6 under the action of gravitational potential energy, and some fine ash particles directly fall into the fine ash collecting bin 6, and the fine ash particles in the fine ash collecting bin 6 are transported to the slag bin 1 through the first gravity-type flap air lock 8 and the fine ash slag dropping pipe 7.

[0021] The gravity flap air lock is also called the heavy hammer flap valve. It can use the weight of the material to automatically unload the ash. It can both unload the material and lock the air. Since it is an existing technology, it will not be described here.

[0022] The secondary separation part can perform secondary separation on the coal slag that has not been transported to the slag bin 1, separate the volume of the coal slag from the gangue particles with relatively large density and transport them to the slag bin 1;

[0023] Specifically, the secondary separation part includes a gravity separation ejection bin 9 which is connected to the fine ash separation pipe 3, a first separation baffle 10 is arranged inside the gravity separation ejection bin 9, a coarse slag collecting bucket 11 is arranged at the lower end of the gravity separation ejection bin 9, a coarse slag collecting bucket 11 is connected to the lower end of the coarse slag collecting bucket 11 through a coarse slag dropping pipe 12, a second gravity flap air lock 13 is arranged between the coarse slag collecting bucket 11 and the coarse slag dropping pipe 12, and the lower end of the coarse slag dropping pipe 12 is connected to the slag bin 1.

[0024] After removing the fine ash particles with a diameter of less than 3 mm, the remaining coal slag uses the height potential energy and the inertia formed by the acceleration of sliding downward obliquely to directly pass the gangue particles with relatively large volume and density through the gravity separation ejection bin 9 and enter the coarse slag collecting bucket 11 during the sliding process. The gangue particles in the coarse slag collecting bucket 11 are transported to the slag bin 1 through the second gravity flap air lock 13 and the coarse slag dropping pipe 12. The coal slag with relatively small remaining gravity potential energy that cannot directly enter the coarse slag collecting bucket 11 enters the tertiary separation section for the third treatment.

[0025] The tertiary separation section is used to perform a tertiary separation on the coal slag that has passed through the secondary separation section but has not been transported to the slag bin 1. The tertiary separation section is used to separate the gangue particles with relatively large volume and density and transport them to the slag bin 1, and the remaining coal slag / raw coal with high calorific value is transported to the boiler.

[0026] Specifically, the three separation parts include a negative pressure separation chamber 14 connected to the gravity separation ejection chamber 9, and also include a negative pressure pipe 15, the negative pressure pipe 15 is connected to the negative pressure separation chamber 14, and an air inlet 16 is provided on one side of the negative pressure separation chamber 14. The coal slag that has not entered the coarse slag collection bucket 11 enters the negative pressure separation chamber 14 after passing through the first separation partition 10. The lower end of the negative pressure separation chamber 14 is provided with a first discharge port 17 and a second discharge port 18. The interior of the negative pressure separation chamber 14 is provided with a second separation partition 19, and the second separation partition 19 is used to In order to transport the coal slag to the first discharge port 17 and the second discharge port 18 respectively, a first discharge pipe 20 is arranged at the lower end of the first discharge port 17, a third gravity flap air lock 22 is arranged between the first discharge port 17 and the first discharge pipe 20, the lower end of the first discharge pipe 20 is through-connected with the feed port of the coal feeder 25, a second discharge pipe 21 is arranged at the lower end of the second discharge port 18, a fourth gravity flap air lock 23 is arranged between the second discharge port 18 and the lower end of the second discharge pipe 21, and the lower end of the second discharge pipe 21 is through-connected with the slag bin 1.

[0027] The negative pressure pipe 15 uses the suction device to suck and pull the coal slag that has not entered the coarse slag collecting bucket 11. This part of the coal slag includes a mixture of coal particles and slag particles with a diameter of more than 3 mm. Since the density of raw coal is less than half of that of gangue, the raw coal is lighter at the same volume. By utilizing the height potential energy and the inertia of acceleration, the remaining larger gangue particles can directly enter the slag bin 1 through the second discharge port 18, the fourth gravity flap air lock 23 and the second discharge pipe 21. The remaining lighter raw coal particles are sucked and pulled to the upper side of the second separation partition 19, and are transported to the coal feeder 25 through the first discharge port 17, the third gravity flap air lock 22 and the first discharge pipe 20. These raw coal particles are reused by the coal feeder 25 to achieve recycling and re-combustion.

[0028] Furthermore, a blocking plate 24 is provided at the lower end of the gravity separation ejection bin 9. The blocking plate 24 is made of a non-transparent material, which can facilitate observation of the situation inside the gravity separation ejection bin 9. At the same time, the blocking plate 24 and the gravity separation ejection bin 9 are detachably connected by sliding connection or bolt connection, which is convenient for inspection and maintenance.

[0029] Through the fine ash separation part, about 40-50% of the total fine ash can be separated and directly fall into the slag bin 1;

[0030] Through the secondary separation part, about 10-20% of the total high-density gangue particles can be separated and directly fall into the slag bin 1;

[0031] Through the three separation parts, 20-30% of the total high-density gangue particles can be separated and directly dropped into the slag bin 1, and the remaining high-calorific value coal slag or raw coal mixture, which accounts for about 5-10% of the total slag discharge, is returned to the furnace for re-combustion.

[0032] The device can separate the unburned raw coal particles in the slag and return them to the furnace for re-combustion, thereby reducing the situation where the slag contains some unburned or even completely large raw coal particles due to the raw coal being mixed with gangue, substandard crushing, excessively large coal particles, and the special design structure of feeding, fluidization, return circulation and slag discharge in the furnace, thereby reducing the waste of raw coal energy.

[0033] In the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

Claims

1. A CFB boiler ash unpowered separation system for unburned coal particles, characterized in that: The invention comprises a slag bin (1), a bucket elevator (2), and also comprises: A fine ash separation section, the fine ash separation section is used to separate fine ash-like coal slag particles from coal slag, and transport the fine ash-like coal slag particles to a slag bin (1); A secondary separation section, which is capable of performing secondary separation on the coal slag that has not been transported to the slag bin (1), and separating the gangue particles in the coal slag and transporting them to the slag bin (1); The tertiary separation section is used to perform a tertiary separation on the coal slag that has passed through the secondary separation section but has not been transported to the slag bin (1). The tertiary separation section is used to separate the gangue particles and transport them to the slag bin (1), and the remaining coal slag / raw coal with a high calorific value is transported to the boiler.

2. The CFB boiler ash unpowered separation system for unburned coal particles according to claim 1 is characterized in that: The fine ash separation section comprises a fine ash separation pipe (3), the bucket elevator (2) has a slag outlet, the fine ash separation pipe (3) is installed at the slag outlet of the bucket elevator (2), the fine ash separation pipe (3) is arranged to be inclined downward, a fine ash sieve plate (4) is arranged at the inner bottom of the fine ash separation pipe (3), the coal slag passing through the slag outlet enters the upper surface of the fine ash sieve plate (4), the lower surface of the fine ash separation pipe (3) is provided with a fine ash collecting plate (5), and the fine ash separation pipe ( The outer surface of the lower end of the coal ash collecting bin (3) is connected to a fine ash collecting bin (6), the fine ash in the coal ash passes through the fine ash sieve plate (4) and enters the fine ash collecting plate (5), and slides down into the fine ash collecting bin (6) under the action of gravity, a fine ash dropping pipe (7) is arranged at the lower end of the fine ash collecting bin (6), a first gravity-type flap air lock (8) is arranged between the fine ash collecting bin (6) and the fine ash dropping pipe (7), and the lower end of the fine ash dropping pipe (7) is connected to the slag bin (1).

3. The CFB boiler ash unpowered separation system for unburned coal particles according to claim 2 is characterized in that: The secondary separation section comprises a gravity separation ejection bin (9) which is in communication with the fine ash separation pipe (3); a first separation baffle (10) is arranged inside the gravity separation ejection bin (9); a coarse slag collection bucket (11) is arranged at the lower end of the gravity separation ejection bin (9); a coarse slag falling pipe (12) is connected to the lower end of the coarse slag collection bucket (11); a second gravity flap air lock (13) is arranged between the coarse slag collection bucket (11) and the coarse slag falling pipe (12); and the lower end of the coarse slag falling pipe (12) is in communication with the slag bin (1).

4. The CFB boiler ash unpowered separation system for unburned coal particles according to claim 3 is characterized in that: The tertiary separation section comprises a negative pressure separation chamber (14) which is connected to the gravity separation ejection chamber (9), and also comprises a negative pressure pipe (15). The negative pressure pipe (15) is connected to the negative pressure separation chamber (14). One side of the negative pressure separation chamber (14) is provided with an air inlet (16). The coal slag that has not entered the coarse slag collection bucket (11) enters the negative pressure separation chamber (14) after passing through the first separation partition (10). The lower end of the negative pressure separation chamber (14) is provided with a first discharge port (17) and a second discharge port (18). The interior of the negative pressure separation chamber (14) is provided with a second separation partition (19). The second separation partition (19) is used to discharge the coal slag into the negative pressure separation chamber (14). The coal slag is transported to a first discharge port (17) and a second discharge port (18) respectively; a first discharge pipe (20) is provided at the lower end of the first discharge port (17); a third gravity-type flap air lock (22) is provided between the first discharge port (17) and the first discharge pipe (20); the lower end of the first discharge pipe (20) is connected to the feed port of a coal feeder (25); a second discharge pipe (21) is provided at the lower end of the second discharge port (18); a fourth gravity-type flap air lock (23) is provided between the second discharge port (18) and the lower end of the second discharge pipe (21); the lower end of the second discharge pipe (21) is connected to the slag bin (1).

5. The CFB boiler ash unpowered separation system for unburned coal particles according to claim 3 is characterized in that: A blocking plate (24) is provided at the lower end of the gravity separation ejection bin (9).

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