Circulating fluidized bed of boiler

Abstract

The utility model discloses a boiler circulating fluidized bed which comprises a combustion furnace, a separator and a return feeder, and the combustion furnace is used for suspension combustion of solid fuel particles; the separator is connected to the combustion furnace and used for receiving smoke generated by the combustion furnace and conducting gas-solid separation, the separator is provided with a gas conveying pipe and an ash outlet channel, and the separator is connected with a post-treatment structure through the gas conveying pipe; one end of the material returning device is connected with the ash discharging channel, the other end of the material returning device is communicated with the combustion furnace, the material returning device is provided with an air chamber, the air chamber is used for air inlet, the bottom of the air chamber is communicated with an ash discharging chamber, the ash discharging chamber is connected with an ash discharging pipe, and ash blowing assemblies are arranged on the circumferential side of the ash discharging chamber in a circumferential array mode. And an air outlet of the ash blowing assembly faces the ash discharging pipe. The soot blowing assembly is arranged on the peripheral side of the ash discharging chamber below the material returning device of the boiler circulating fluidized bed, so that accumulated soot in the ash discharging chamber can be conveniently and irregularly discharged, and blockage caused by the accumulated soot is avoided.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the technical field of boiler, especially relates to a boiler circulating fluidized bed. BACKGROUND

[0002] The circulating fluidized bed boiler is widely applied in the power station boiler in China, adopts the fluidization combustion technology, and the core structure includes a combustion chamber and a circulating loop. In the combustion process, the unburned fly ash is separated through a cyclone separator, is returned to the combustion furnace through a return feeder for secondary combustion, and the thermal efficiency of the boiler is improved.

[0003] Part of the fly ash falls in the ash discharge chamber and is collected, and is discharged through an ash discharge pipe connected to the ash discharge chamber after a period of time. Due to the shape of the ash discharge chamber and long-term accumulation, part of the fly ash adheres or agglomerates, is not easy to fall off or block from the inner wall of the ash discharge chamber, and long-term affects the ash discharge effect. UTILITY MODEL CONTENT

[0004] In order to solve the above problems, the utility model provides a boiler circulating fluidized bed, which can set the ash blowing assembly to blow the accumulated ash adhered to the ash discharge chamber, so as to achieve the purpose of loosening, facilitate the periodic removal of the ash discharge chamber, and avoid the blockage caused by long-term incomplete removal.

[0005] In order to achieve the above purpose, the utility model adopts the technical scheme that:

[0006] A boiler circulating fluidized bed, comprising:

[0007] A combustion furnace for performing suspended combustion of solid fuel particles;

[0008] A separator connected to the combustion furnace for receiving flue gas generated by the combustion furnace and performing gas-solid separation, the separator having a gas conveying pipe and an ash discharge passage, the separator being connected with a post-processing structure through the gas conveying pipe; and

[0009] A return feeder, one end of which is connected with the ash discharge passage and the other end of which is communicated with the combustion furnace, the return feeder having an air chamber for air inlet, the bottom of the air chamber being provided with an ash discharge chamber in communication, the ash discharge chamber being connected with an ash discharge pipe, the ash discharge chamber being provided with ash blowing assemblies in a circumferential array on the side, and the air outlet of the ash blowing assembly being arranged towards the ash discharge pipe.

[0010] Preferably, the ash blowing assembly comprises a compressed air fan, an air pipe and a spray head, one end of the spray head being provided through the cavity wall of the ash discharge chamber, and the other end of the spray head being connected with the compressed air fan through the air pipe.

[0011] Preferably, the ash discharging chamber is provided with a limiting hole, and a sealing member is arranged on the hole wall of the limiting hole, and the nozzle is installed in the ash discharging chamber through the limiting hole and the sealing member.

[0012] Preferably, each nozzle is provided with an electric control assembly, the electric control assembly comprises a main controller and an electric control valve, the electric control valve is arranged at one end of the nozzle connected to the air pipe and is electrically connected with the main controller, and the main controller controls the electric control valve to be sequentially opened and closed.

[0013] Preferably, the return device further comprises a U-shaped return chamber, a return leg and a vertical pipe, one end of the vertical pipe is connected to the ash discharging passage, the other end of the vertical pipe is communicated with the return leg through the U-shaped return chamber, and the U-shaped return chamber is arranged below the air chamber.

[0014] Preferably, the U-shaped return chamber is provided with a wind distribution plate and a wind cap, the wind distribution plate is connected to the air chamber, and the wind cap is arranged on the surface of the wind distribution plate away from the air chamber.

[0015] Preferably, the air chamber is provided with two air chambers, and the two air chambers are arranged below the U-shaped return chamber in parallel to form independent air inlet spaces.

[0016] Preferably, the ash discharging pipe is provided with an ash discharging valve for controlling the opening and closing of the ash discharging pipe.

[0017] Compared with the prior art, the ash discharging chamber of the present application has the following beneficial effects:

[0018] The blowing assembly is arranged on the side of the ash discharging chamber below the return device of the boiler circulating fluidized bed, the air outlet of the nozzle is arranged towards the ash discharging pipe, the electric control assembly controls the nozzle to blow the cavity wall of the ash discharging chamber according to a set sequence, and the accumulated ash adhered to the ash discharging chamber is loosened, so that the accumulated ash in the ash discharging chamber can be conveniently and irregularly removed, and the blockage caused by the accumulated ash is avoided. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 is a structural schematic view of the boiler circulating fluidized bed of the present application;

[0020] Figure 2 is a sectional view of the return device in the boiler circulating fluidized bed of the present application;

[0021] Figure 3 is Figure 2 is an enlarged view of A in FIG.

[0022] In the drawings, 1 is a combustion furnace, 2 is a separator, 21 is a gas conveying pipe, 22 is an ash outlet, 3 is a return feeder, 31 is a wind chamber, 32 is an ash discharging chamber, 321 is an ash discharging pipe, 322 is a limiting hole, 33 is a soot blowing assembly, 331 is a compressed air fan, 332 is an air pipe, 333 is a nozzle, 334 is an electric control valve, 34 is a sealing element, 35 is a U-shaped return chamber, 351 is a wind distribution plate, 352 is a wind cap, 353 is a dilute phase zone, 354 is a dense phase zone, 36 is a return leg, 37 is a standpipe, 4 is a post-treatment structure, and 5 is an ash discharging valve. DETAILED DESCRIPTION

[0023] To make the objectives, technical solutions and advantages of the present application clearer, the following further describes the embodiments of the present application in conjunction with the drawings.

[0024] The following description of the example embodiments refers to the accompanying drawings, wherein like numbers refer to like or similar elements throughout. The following description of the example embodiments is not representative of all possible embodiments consistent with the present application. Rather, it is merely intended to describe some embodiments consistent with the present application in further detail as detailed in the claims.

[0025] In the description of the present application, it should be understood that the terms "first", "second", etc. are used only for the purpose of description, and should not be understood as indicating or implying relative importance. For those skilled in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances. In addition, in the description of the present application, "a plurality of" means two or more, unless otherwise specified. "And / or", which describes the relationship between the associated objects, means that there can be three relationships, for example, A and / or B can mean that there are three cases of A alone, A and B together, and B alone. The character " / " generally represents an "or" relationship between the associated objects.

[0026] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs. The terms used in the specification of the present application are only for the purpose of describing the specific embodiments, and are not intended to limit the present application. The term "and / or" used herein includes any and all combinations of one or more associated listed items.

[0027] To solve the above problems, please refer to Figures 1 to 3The utility model provides a kind of boiler circulating fluidized bed, including combustion furnace 1, separator 2 and return feeder 3, the combustion furnace 1 is used to carry out the suspension combustion of solid fuel particles;The separator 2 is connected to the combustion furnace 1, for receiving the flue gas generated by the combustion furnace 1 and carrying out gas-solid separation, the separator 2 has gas pipe 21 and ash outlet channel 22, the separator 2 is connected with post-processing structure 4 by gas pipe 21;The return feeder 3 is connected with the ash outlet channel 22 in one end, and the other end is communicated with the combustion furnace 1, the return feeder 3 has a wind chamber 31, and the wind chamber 31 is used for air intake, and the bottom of the wind chamber 31 is connected with ash removal chamber 32, and the ash removal chamber 32 is connected with ash removal pipe 321, and the periphery of the ash removal chamber 32 is circumferentially arranged with ash blowing assembly 33, and the air outlet of the ash blowing assembly 33 is arranged towards the ash removal pipe 321.

[0028] The separator 2 is a spiral separator 2, which is an equipment for separating particles of different densities by centrifugal force and gravity. It is widely used in mining, chemical industry, environmental protection and other fields. The flue gas generated by the combustion furnace 1 enters the spiral separator 2, and the high-speed centrifugal force makes the fly ash be thrown to the outer wall and fall along the wall, while the hot air is discharged to the next process through the gas pipe 21. The main function of the combustion furnace 1 is to provide a combustion space, transfer heat, discharge flue gas, maintain stable combustion, protect the furnace wall and collect ash, to ensure efficient and safe operation of the boiler. Further, a cold slag machine and an ignition device are arranged below the combustion furnace 1. The cold slag machine is used to cool the solid fuel particle slag, and the ignition device is used to provide a fire source. The post-processing structure 4 includes a superheater, an economizer, an air preheater and a dust collector. The main function of the return feeder 3 is to send the unburned fly ash back to the combustion furnace 1 to improve the combustion efficiency and reduce emissions.

[0029] In an optional embodiment, as Figure 2As shown, the soot blowing assembly 33 includes a compressed air blower 331, an air pipe 332, and a spray head 333, one end of the spray head 333 is provided in the cavity wall of the soot discharging chamber 32, and the other end is connected with the compressed air blower 331 through the air pipe 332; the soot discharging chamber 32 is provided with a limiting hole 322, and the hole wall of the limiting hole 322 is provided with a sealing element 34, and the spray head 333 is installed in the soot discharging chamber 32 through the limiting hole 322 and the sealing element 34. The compressed air blower 331 provides the required pressure and flow by compressing air or other gas to cooperate with the spray head 333 to blow and loosen the accumulated ash; wherein the number, air volume and air speed and other parameters of the spray head 333 are selected or adjusted according to the scale of the boiler, in this embodiment, the spray head 333 is provided with three and is circumferentially arrayed in the soot discharging chamber 32, specifically, a plurality of limiting holes 322 are provided on the side of the soot discharging chamber 32, and the sealing elements 34 are welded and connected at the limiting holes 322, the surface of the sealing elements 34 towards the center thereof is provided with a sealing rubber strip, the spray head 333 is provided in the limiting hole 322, and cooperates with the sealing rubber strip to stably and sealingly set the spray head 333, thereby improving the sealing performance of the air chamber 31; meanwhile, the spray head 333 includes a main body and a nozzle, both the main body and the nozzle are hollow structures, one end of the main body is communicated with the air pipe 332, and the other end is communicated with the nozzle, the nozzle and the main body are arranged at an included angle, and the air outlet of the nozzle is towards the center periphery of the soot discharging pipe 321, and blows and loosens the accumulated ash on the side of the end portion of the soot discharging pipe 321 connected with the soot discharging chamber 32.

[0030] In optional embodiments, as shown in Figure 3 each spray head 333 is provided with an electric control assembly, the electric control assembly includes a main controller and an electric control valve 334, the electric control valve 334 is arranged at one end of the spray head 333 connected with the air pipe 332, and is electrically connected with the main controller, and the main controller controls the electric control valve 334 to be sequentially opened and closed. The main controller is an automatic system such as PLC, DCS, microcontroller, etc., automatically sends an electric signal to the electric control valve 334 according to the sensor feedback to control the operation of the electric control valve 334, edits the running time of the main controller and the time point of opening of the electric control valve 334, so that the spray head 333 sprays in sequence, avoids the offset of the opposite spray, improves the blowing and loosening of the accumulated ash on the end portion of the soot discharging pipe 321 by the nozzle, and makes the accumulated ash discharged through the soot discharging pipe 321.

[0031] In optional embodiments, as shown in Figure 2As shown, the returner 3 further comprises a U-shaped return chamber 35, a return leg 36, and a vertical pipe 37, one end of the vertical pipe 37 is connected with the ash outlet channel 22, the other end is communicated with the return leg 36 through the U-shaped return chamber 35, the U-shaped return chamber 35 is provided below the air chamber 31, the U-shaped return chamber 35 is provided with an air distribution plate 351 and a wind cap 352, the air distribution plate 351 is connected with the air chamber 31, and the wind cap 352 is arranged on the surface of the air distribution plate 351 away from the air chamber 31. The U-shaped return chamber 35 is formed into a U-shaped channel by arranging a baffle, after the fly ash enters the returner 3 through the separator 2, the fly ash falls due to gravity, the wind cap 352 blows upward, and the small particles which are not fully combusted are lifted to be suspended, in order to form a sparse phase area 353 and a dense phase area 354, the wind cap 352 on the air distribution plate 351 is gradually densified from the material inlet to the return port, the wind cap 352 comprises a small-hole wind cap and a large-hole wind cap, the small-hole wind cap is located in the sparse phase area 353, the large-hole wind cap is located in the dense phase area 354, the number of the wind cap 352 is gradually increased from the sparse phase area 353 to the dense phase area 354, the suspended fly ash flows from the sparse phase area 353 to the dense phase area 354 under the action of negative pressure, and enters the inlet of the return leg 36 upward under the pushing of the large-hole wind cap, due to the action of gravity, the fly ash gradually falls, the return leg 36 is designed to be downwardly inclined, so that the material is smoothly returned into the combustion furnace 1 to form a circulating loop, and the fly ash which is not fully combusted continues to be combusted.

[0032] In optional embodiments, as shown in Figure 2 As shown, the air chamber 31 is provided with two air chambers 31 which are arranged side by side below the U-shaped return chamber to form independent air inlet spaces. Specifically, the two air chambers 31 correspond to the sparse phase area 353 and the dense phase area 354 respectively, and provide independent air inlet spaces for the wind caps 352 corresponding to the sparse phase area 353 and the dense phase area 354 respectively to meet the air volume demand of the corresponding areas.

[0033] In optional embodiments, as shown in Figure 2 As shown, the ash discharge pipe 321 is provided with an ash discharge valve 5 for controlling the opening and closing of the ash discharge pipe 321. The ash discharge valve 5 is automatically opened or manually opened, when the ash discharge valve 5 is closed, the fly ash which is not circulated into the combustion furnace 1 falls and accumulates in the ash discharge chamber 32, after a certain degree of accumulation or a period of time, the ash discharge valve 5 is manually or automatically opened to discharge the accumulated ash in the ash discharge chamber 32.

[0034] The flue gas enters the separator 2 to separate fly ash and hot gas, the hot gas is transported from the gas conveying pipe 21 to the post-processing structure 4, the fly ash falls into the returner 3 through the ash outlet channel 22, part of the fly ash enters the return leg 36 through the U-shaped channel and then is circulated back to the combustion furnace 1, and part of the fly ash falls in the ash discharge chamber 32 and accumulates, after a certain degree of accumulation or a period of time, the ash discharge valve 5 is manually or automatically opened to discharge the accumulated ash in the ash discharge chamber 32, and the fly ash attached to the inner wall of the ash discharge chamber 32 is blown off by cooperating with the spray head 333.

[0035] In summary, the soot blowing assembly 33 is arranged on the side of the ash discharge chamber 32 below the return feeder 3 of the boiler circulating fluidized bed, the air outlet of the nozzle is arranged towards the ash discharge pipe 321, and the electric control assembly controls the nozzle to blow the cavity wall of the ash discharge chamber 32 according to a set order, so that the accumulated ash adhered to the ash discharge chamber 32 is loosened, the accumulated ash in the ash discharge chamber 32 is conveniently removed at irregular intervals, and blockage caused by the accumulated ash is avoided.

[0036] The same or similar reference numerals in the drawings of the embodiments correspond to the same or similar components; in the description of the utility model, it is understood that if the orientations or position relationships indicated by the terms "upper", "lower", "left", "right" and the like are based on the orientations or position relationships shown in the drawings, they are only for the convenience of describing the utility model and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, therefore, the terms describing the position relationship in the drawings are only used for exemplary illustration, and cannot be understood as a limitation on the utility model, for ordinary skilled persons in the art, the specific meanings of the above terms can be understood according to the specific circumstances.

[0037] The above is only a preferred embodiment of the utility model, and does not limit the utility model, any modification, equivalent replacement and improvement made within the spirit and principle of the utility model should be included in the protection scope of the utility model.

Claims

1. A boiler circulating fluidized bed, characterized in that, include: A combustion furnace, wherein the combustion furnace is used for the suspension combustion of solid fuel particles; A separator, connected to the combustion furnace, for receiving flue gas generated by the combustion furnace and performing gas-solid separation, the separator having a gas delivery pipe and an ash discharge channel, and the separator being connected to a post-treatment structure via the gas delivery pipe; and... The return feeder has one end connected to the ash discharge channel and the other end connected to the combustion furnace. The return feeder has an air chamber for air intake. An ash discharge chamber is connected to the bottom of the air chamber. An ash discharge pipe is connected to the ash discharge chamber. A soot blowing assembly is arranged in a circumferential array on the periphery of the ash discharge chamber. The air outlet of the soot blowing assembly is oriented towards the ash discharge pipe.

2. The boiler circulating fluidized bed according to claim 1, characterized in that, The soot blowing assembly includes a compressed blower, an air duct, and a nozzle. One end of the nozzle is inserted through the cavity wall of the ash discharge chamber, and the other end is connected to the compressed blower through the air duct.

3. The boiler circulating fluidized bed according to claim 2, characterized in that, The ash discharge chamber has a limiting hole, and the wall of the limiting hole is provided with a sealing element. The nozzle is installed in the ash discharge chamber through the limiting hole and the sealing element.

4. The boiler circulating fluidized bed according to claim 2 or 3, characterized in that, Each of the nozzles is equipped with an electronic control component, which includes a main controller and an electronic control valve. The electronic control valve is located at one end of the nozzle connected to the air duct and is electrically connected to the main controller. The main controller controls the electronic control valve to open and close sequentially.

5. The boiler circulating fluidized bed according to claim 1, characterized in that, The return feeder also includes a U-shaped return chamber, a return leg, and a riser. One end of the riser is connected to the ash discharge channel, and the other end is connected to the return leg through the U-shaped return chamber. The air chamber is provided below the U-shaped return chamber.

6. The boiler circulating fluidized bed according to claim 5, characterized in that, The U-shaped return chamber is equipped with an air distribution plate and an air cap. The air distribution plate is connected to the air chamber, and the air cap is disposed on the surface of the air distribution plate opposite to the air chamber.

7. The boiler circulating fluidized bed according to claim 6, characterized in that, There are two air chambers, which are arranged side by side below the U-shaped return material chamber to form an independent air intake space.

8. The boiler circulating fluidized bed according to claim 1, characterized in that, The ash discharge pipe is equipped with an ash discharge valve to control the opening and closing of the ash discharge pipe.

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