A stacked fluidized bed

Abstract

The present invention discloses a laminated fluidized bed, which comprises a furnace body. A feed inlet is arranged at the top of the furnace chamber, and a slag discharge port is arranged at the bottom. A plurality of fluidized beds are arranged vertically in the furnace chamber. Each fluidized bed includes a positive conical gas collecting pipe cover arranged at the center of the furnace chamber and an inverted conical fluidized bed body installed on the inner wall of the furnace chamber. Coal particles flow from the upper inverted conical fluidized bed body to the side wall of the lower positive conical gas collecting pipe cover. Air ducts are annularly distributed on the inner wall of the furnace chamber corresponding to each fluidized bed. The upper and lower adjacent air ducts are not connected. Each air duct is connected with a blowing device. A blowing nozzle is arranged below each inverted conical fluidized bed body corresponding to the same layer of air duct. The air ejected from the blowing nozzle enters the adjacent gas collecting pipe cover through the interval between the upper and lower inverted conical fluidized bed bodies and the interval between the upper and lower gas collecting pipe covers. In the present invention, the coal bed thickness is relatively uniform, which is convenient for accurately controlling the combustion state and working temperature of each layer. The coal particles are in a flowing combustion state, which is beneficial to the redox reaction of all coal particles and improves the combustion efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of combustion furnaces, and particularly relates to a laminated fluidized bed. Background Art

[0002] For stoker boilers, in order to improve the combustion power, reduce the blast air pressure and power consumption, it is usually necessary to increase the effective area of the coal bed; since the bed adopts a mechanical transmission moving mode, the coal layer is basically in a fixed combustion state, which is not conducive to redox reactions; as the advancing coal layer continues to burn, the thickness of the coal layer will become thinner and thinner. Therefore, it is difficult to accurately control the air pressure at each combustion stage, and the excess air coefficient is difficult to accurately control, resulting in fluctuations in combustion efficiency and the generation of NOx. Summary of the Invention

[0003] In view of the deficiencies in the prior art, the present invention provides a laminated fluidized bed.

[0004] The present invention discloses a laminated fluidized bed, including a furnace body,

[0005] The top of the furnace chamber of the furnace body is provided with a feed inlet, the bottom of the furnace chamber is provided with a slag discharge port, and a plurality of fluidized beds are arranged at intervals in the vertical direction inside the furnace chamber;

[0006] Each layer of the fluidized bed includes a positive conical gas collecting pipe cover arranged at the center of the furnace chamber and an inverted conical fluidized bed body installed on the inner wall of the furnace chamber. The inverted conical fluidized bed body is composed of grates that are annularly arranged on the inner wall of the furnace chamber and slope downward; coal particles flow from the upper inverted conical fluidized bed body to the side wall of the lower positive conical gas collecting pipe cover;

[0007] Air ducts are annularly arranged on the inner wall of the furnace chamber corresponding to each layer of the fluidized bed. The upper and lower adjacent air ducts are not connected, and each layer of air duct is connected with a blast device;

[0008] A blast nozzle is provided below each layer of the air duct corresponding to the same layer of the inverted conical fluidized bed body. The air ejected from the blast nozzle enters the upper and lower positive conical gas collecting pipe covers through the grate, the interval between the upper and lower inverted conical fluidized bed bodies, and the interval between the upper and lower positive conical gas collecting pipe covers.

[0009] As a further improvement of the present invention, the upper and lower multiple positive conical gas collecting pipe covers are coaxially arranged, and exhaust holes are provided at the top of each layer of the positive conical gas collecting pipe cover.

[0010] As a further improvement of the present invention,

[0011] It further includes a material leveling cone;

[0012] The material leveling cone is arranged inside the furnace chamber corresponding to the position of the feed inlet, and the bottom of the material leveling cone is connected to the flue gas exhaust hood. Exhaust ports are annularly distributed around the flue gas exhaust hood.

[0013] The exhaust holes of the uppermost positive conical gas collecting pipe hood communicate with the flue gas exhaust hood.

[0014] As a further improvement of the present invention, a plurality of strip-shaped ventilation grooves are provided on the grate.

[0015] As a further improvement of the present invention, the inclination angle of the grate downward is not less than 30 degrees and not more than 70 degrees.

[0016] As a further improvement of the present invention, a blast inlet connected to the blast device is provided on the outer wall of each layer of the air duct, and a plurality of blast nozzles are annularly distributed below the inverted conical fluidized bed body of the same layer corresponding to the inner wall of each layer of the air duct.

[0017] As a further improvement of the present invention, the blast device includes, but is not limited to, a blower and a damper.

[0018] As a further improvement of the present invention, the bottom of the furnace chamber has a conical structure, and a slag discharge port is provided at the bottom of the conical structure.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0020] By arranging multiple fluidized beds in the furnace chamber, the present invention can achieve a large effective area of the bed with a small floor area, thereby improving the combustion power.

[0021] In the present invention, the coal bed thicknesses of each layer of the fluidized bed can be the same, which is beneficial to balancing the penetration pressure of the blast for each coal bed. Moreover, the "zigzag" coal particle flow passage formed by the multiple fluidized beds enables the coal particles to flow naturally under the action of gravity without mechanical drive, with a simple structure, low failure rate and no drive power consumption. Since the coal particles are always in a flowing combustion state, it is beneficial to the oxidation-reduction reaction of all coal particles.

[0022] In the present invention, different air ducts are provided for each layer of the fluidized bed, and each air duct is provided with devices such as blast and dampers. By adjusting the blast volume of each layer, precise control of the combustion state and working temperature of the coal particles in each layer can be achieved, effectively avoiding the generation of NOx. Description of the Drawings

[0023] Figure 1 It is a side sectional view of the structure of a laminated fluidized bed disclosed in an embodiment of the present invention.

[0024] In the figure:

[0025] 1. Furnace; 11. Feed inlet; 12. Slag discharge port; 2. Material leveling cone; 31. Positive conical gas collecting pipe cover; 32. Inverted conical fluidized bed body; 4. Air duct; 41. Blowing nozzle; 42. Blowing inlet; 5. Flue gas exhaust hood; 61. First support; 62. Second support. Detailed implementation mode

[0026] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some but not all of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0027] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be construed as a limitation of the present invention. In addition, the terms "first", "second", and "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0028] In the description of the present invention, it should also be noted that unless otherwise clearly specified and limited, the terms "installation", "connection", and "connection" 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 direct mechanical connection, or an indirect connection through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0029] The following will further describe the present invention in detail with reference to the accompanying drawings:

[0030] As Figure 1 shown, the present invention provides a laminated fluidized bed, including a furnace body 1. A feed inlet 11 is provided at the top of the furnace chamber 1 of the furnace body 1, and a slag discharge port 12 is provided at the bottom of the furnace chamber 1. A plurality of layers of fluidized beds are arranged at intervals in the vertical direction inside the furnace chamber 1; each layer of fluidized bed includes a positive conical gas collecting pipe cover 31 provided at the center of the furnace body and an inverted conical fluidized bed body 32 installed on the inner wall of the furnace chamber 1. The inverted conical fluidized bed body 32 is composed of grates that are annularly arranged on the inner wall of the furnace body and inclined downward; a plurality of strip-shaped ventilation grooves are provided on the grates, and coal particles flow from the upper inverted conical fluidized bed body 32 to the side wall of the lower positive conical gas collecting pipe cover 31;

[0031] On the inner wall of the furnace chamber 1, air ducts 4 are annularly arranged corresponding to each fluidized bed layer. The upper and lower adjacent air ducts 4 are not connected, and each air duct 4 is connected with a blower device; below each air duct 4 corresponding to the inverted conical fluidized bed body 32 of the same layer, there is an air injection nozzle 41. The air ejected from the air injection nozzle 41 enters the upper and lower positive conical gas collecting hoods 31 through the ventilation slots on the grate, the interval between the upper and lower two-layer inverted conical discharge hoppers 32, and the interval between the upper and lower two-layer positive conical gas collecting hoods 31.

[0032] By arranging multiple fluidized bed layers in the furnace chamber 1 of the present invention, a large effective area of the bed body can be achieved with a smaller floor area, thereby improving the combustion power;

[0033] In the present invention, the coal bed thicknesses of each fluidized bed layer can be the same, which is beneficial to balancing the penetration pressure of the air blast for each coal bed. Moreover, the "zigzag" coal particle flow passage formed by the multiple fluidized bed layers enables the coal particles to flow naturally under the action of gravity without mechanical drive, with a simple structure, low failure rate and no drive power consumption. Since the coal particles are always in a flowing combustion state, it is beneficial to the redox reaction of all coal particles.

[0034] In the present invention, different air ducts 4 are arranged for each fluidized bed layer, and each air duct 4 is provided with a blower device. By adjusting the air blast volume of each layer, precise control of the combustion state and working temperature of each layer of coal particles can be achieved, effectively avoiding the generation of NOx.

[0035] Specifically:

[0036] As Figure 1 shown, in the present invention, the upper and lower multiple positive conical gas collecting hoods 31 are coaxially arranged, and exhaust holes are provided at the top of each positive conical gas collecting hood 31.

[0037] Furthermore, the present invention further includes a material leveling cone 2; the material leveling cone 2 is arranged inside the furnace chamber 1 corresponding to the position of the feed inlet 11, and the bottom of the material leveling cone 2 is connected with the flue gas exhaust hood 5. Exhaust ports are annularly arranged around the flue gas exhaust hood 5; the exhaust ports in the present invention face the inside of the furnace chamber 1, and the exhaust holes of the uppermost positive conical gas collecting hood 31 are communicated with the flue gas exhaust hood 5. After the flue gas generated by the combustion of coal particles inside the furnace chamber 1 passes through the positive conical gas collecting hood 31 in sequence, it enters the flue gas exhaust hood 5 and is sprayed into the furnace chamber 1 through the exhaust ports around the flue gas exhaust hood 5. The arrangement of the material leveling cone 2 can make the coal particles entering the furnace chamber 1 through the feed inlet 11 be evenly dispersed and fall on the fluidized bed body.

[0038] Furthermore, in the present invention, the upper positive conical gas collecting hood 31 is fixedly installed on the lower positive conical gas collecting hood 31 through a second support 62, and the lowermost positive conical gas collecting hood 31 is fixedly connected to the inner wall of the bottom of the furnace chamber 1 through a first support 61. The fixed connection in the present invention includes welding.

[0039] Further, in the present invention, a zigzag coal particle flow passage for the flow of coal particles is formed between the positive conical gas collecting pipe cover 31 and the inverted conical fluidized bed body 32 in the multi-layer fluidized bed, so as to realize the natural downward flow of coal particles. During actual operation, the coal particles entering the interior of the furnace 1 pass through the material leveling cone 2 and are evenly scattered on the inverted conical fluidized bed body 32 of the first-layer fluidized bed, and then slide down from the inverted conical fluidized bed body 32 of the first-layer fluidized bed to the side wall of the positive conical gas collecting pipe cover 31 of the second layer. After being blocked by the side wall of the positive conical gas collecting pipe cover 31 of the second layer, they slide down to the inverted conical fluidized bed body 32 of the second-layer fluidized bed. Repeat the above steps until they slide to the bottom of the furnace 1, and the burned slag is discharged from the slag discharge port 12 at the bottom of the furnace 1.

[0040] Further, in the present invention, the downward inclination angle of the grate is not less than 30 degrees and not more than 70 degrees.

[0041] Further, a blast inlet 42 connected to the blast device is provided on the outer wall of each layer of air duct 4 in the present invention, and a plurality of blast nozzles 41 are annularly arranged on the inner wall of each layer of air duct 4 corresponding to the lower part of the inverted conical fluidized bed body 32 of the same layer.

[0042] Further, the blast device in the present invention includes but is not limited to a blower and a damper. The setting of the blower and the damper can realize the adjustment of the air volume and air pressure of each layer of air duct 4 at any time, so as to accurately control the combustion state and working temperature of the coal particles in each layer. During actual operation, the air sent by the blower and the damper passes through the corresponding air duct 4 and then enters the lower part of the same-layer fluidized bed inclined downward through the blast nozzles 41 on the inner wall of the air duct 4. Subsequently, the air passes through the burning coal layer and enters the positive conical gas collecting pipe covers 31 above and below. Finally, the flue gas after the redox reaction is collected in the uppermost positive conical gas collecting pipe cover 31 and is sprayed into the furnace 1 through the exhaust port of the flue gas exhaust hood 5 below the material leveling cone 2.

[0043] Further, the bottom of the furnace 1 in the present invention has a conical structure, and a slag discharge port 12 is provided at the bottom of the conical structure.

[0044] Further, the number of layers of the fluidized bed provided inside the furnace 1 in the present invention is 3 layers, and the number of layers of the fluidized bed provided in the present invention can also be increased or decreased according to the actual working conditions.

[0045] Further, the laminated fluidized bed disclosed in the present invention can be used in various fields such as pyrolysis, combustion, and drying of solid materials.

[0046] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A stacked fluidized bed, comprising a furnace body, characterized in that, The furnace top of the furnace body is provided with a feed inlet, the bottom of the furnace chamber is provided with a slag discharge port, and a plurality of fluidized beds are arranged at intervals along the vertical direction inside the furnace chamber; Each layer of the fluidized bed includes a positive conical gas collecting pipe cover arranged at the center of the furnace chamber and an inverted conical fluidized bed body installed on the inner wall of the furnace chamber. The inverted conical fluidized bed body is composed of a grate that is circumferentially arranged on the inner wall of the furnace chamber and slopes downward; coal particles flow from the upper layer of the inverted conical fluidized bed body to the side wall of the lower layer of the positive conical gas collecting pipe cover; Air ducts are circumferentially arranged on the inner wall of the furnace chamber corresponding to each layer of the fluidized bed. The upper and lower adjacent air ducts are not connected, and each layer of the air duct is connected with a blowing device; A blowing nozzle is provided below each layer of the air duct corresponding to the same layer of the inverted conical fluidized bed body. The air ejected from the blowing nozzle enters the upper and lower layers of the positive conical gas collecting pipe covers through the grate, the space between the upper and lower layers of the inverted conical fluidized bed bodies, and the space between the upper and lower layers of the positive conical gas collecting pipe covers.

2. The stacked fluidized bed according to claim 1, characterized in that, The upper and lower multiple layers of the positive conical gas collecting pipe covers are coaxially arranged, and exhaust holes are provided at the top of each layer of the positive conical gas collecting pipe cover.

3. The stacked fluidized bed according to claim 1, characterized in that, It also includes a material leveling cone; The material leveling cone is arranged inside the furnace chamber corresponding to the position of the feed inlet, and the bottom of the material leveling cone is connected with a flue gas exhaust hood. Exhaust ports are circumferentially arranged around the flue gas exhaust hood; The exhaust holes of the topmost layer of the positive conical gas collecting pipe cover are communicated with the flue gas exhaust hood.

4. The stacked fluidized bed according to claim 1, wherein A plurality of strip-shaped ventilation grooves are provided on the grate.

5. The stacked fluidized bed according to claim 1, wherein The downward inclination angle of the grate is not less than 30 degrees and not more than 70 degrees.

6. The stacked fluidized bed according to claim 1, characterized in that, A blowing inlet connected with the blowing device is provided on the outer wall of each layer of the air duct, and a plurality of the blowing nozzles are circumferentially arranged on the inner wall of each layer of the air duct corresponding to the lower part of the same layer of the inverted conical fluidized bed body.

7. The stacked fluidized bed according to claim 6, characterized in that, The blowing device includes a blower and a throttle valve.

8. The stacked fluidized bed according to claim 1, characterized in that, The bottom of the furnace chamber is of a conical structure, and the slag discharge port is provided at the bottom of the conical structure.

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