Novel strong penetration jet flow structure secondary air burner suitable for circulating fluidized bed boiler

Abstract

The invention relates to the field of circulating fluidized bed boilers, and discloses a novel strong-penetration jet flow structure secondary air burner suitable for a circulating fluidized bed boiler, which comprises a secondary air pipe, an auxiliary air pipe is fixedly arranged in the secondary air pipe, and one end of the secondary air pipe and one end of the auxiliary air pipe are fixedly connected with one end of the inner wall of the boiler respectively. A plurality of adjusting assemblies are fixedly installed on the outer side of the secondary air pipe, a partition assembly is fixedly installed in an annular area defined by the inner side of the secondary air pipe and the outer side of the auxiliary air pipe, an inner movable plate is rotationally connected into the auxiliary air pipe, and an inclined adjusting assembly fixedly connected with one end of the inner movable plate is fixedly installed on the outer wall of the secondary air pipe. The device can be continuously put into use when the boiler runs in an ultra-low load mode, the normal function of a secondary air combustor can be achieved, the burn-off rate is increased, the combustion stability of the boiler is guaranteed, the effects of secondary air disturbance strengthening and burnout assisting under the low-load working condition of the boiler are achieved, the generation amount of NOx in the boiler is reduced to the maximum extent, and the environmental protection index requirement is met.

Description

Technical Field

[0001] The invention relates to the field of circulating fluidized bed boilers, in particular to a novel secondary air burner with a strong penetrating flow structure suitable for circulating fluidized bed boilers. Background Art

[0002] With the large-scale and high-parameterization of circulating fluidized bed (CFB) boilers, the furnace height continues to increase, which brings problems to the boiler foundation, structural layout and manufacturing cost. Reasonable setting of the boiler furnace heating surface after the large-scale CFB boiler is a problem that must be solved. On the other hand, since the jet momentum of the secondary air of the CFB boiler is smaller than the fluidization momentum of the bed material in the dense phase area, the secondary air of the CFB boiler with an increasing furnace cross-sectional area is difficult to reach the center of the furnace, causing the center of the furnace to be in an oxygen-deficient state. Experiments have shown that oxygen deficiency in the center of the furnace is common in large-scale circulating fluidized bed boilers, resulting in incomplete fuel combustion, especially high combustibles in the boiler fly ash, which reduces the combustion efficiency of the CFB boiler. Therefore, the problem of insufficient secondary air penetration after the large-scale CFB boiler also needs to be solved.

[0003] For a circulating fluidized bed boiler, in order to ensure the fluidization effect of the furnace bed when the boiler is running at ultra-low load, the primary air volume at the furnace bottom must be higher than the minimum air volume required for fluidization. This results in the primary air volume at the furnace bottom being much larger than the primary air volume required for combustion when the boiler is running at ultra-low load, which also results in a reduction in the secondary air volume when the boiler is running at ultra-low load. As a result, the secondary air rate and wind speed are difficult to meet the combustion design requirements, and the effect of the secondary air cannot be fully realized, which directly affects the ultra-low load flexibility of the circulating fluidized bed boiler. To this end, the present invention proposes a new type of strong penetrating flow structure secondary air burner suitable for circulating fluidized bed boilers to solve the above problems. Summary of the invention

[0004] The object of the present invention is to provide a new type of secondary air burner with strong penetrating flow structure suitable for a circulating fluidized bed boiler, so as to solve the problems raised in the above background technology.

[0005] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a new type of strong penetrating permeation structure secondary air burner suitable for a circulating fluidized bed boiler, comprising a secondary air duct, an auxiliary air duct is fixedly arranged inside the secondary air duct, and one end of the secondary air duct and the auxiliary air duct are respectively fixedly connected to one end of the inner wall of the boiler, a plurality of adjustment components are fixedly installed on the outside of the secondary air duct, and a partition component is fixedly installed in the annular area surrounded by the inner side of the secondary air duct and the outer side of the auxiliary air duct, an inner movable plate is rotatably connected inside the auxiliary air duct, and an oblique adjustment component fixedly connected to one end of the inner movable plate is fixedly installed on the outer wall of the secondary air duct; the partition component comprises a fixed partition plate arranged between the secondary air duct and the auxiliary air duct, and the fixed partition plate is an annular structure, the outer side and the inner side of the fixed partition plate are respectively fixedly connected to the inner wall of the secondary air duct and the outer side of the auxiliary air duct, and a plurality of through grooves are opened on the surface of the fixed partition plate; each through groove of the fixed partition plate is respectively provided with an outer movable partition plate matching the shape thereof, and each outer movable partition plate is respectively in smooth contact with the inner wall of the through groove corresponding to the fixed partition plate.

[0006] Preferably, the oblique adjustment assembly and each adjustment assembly include an adjustment block fixedly connected to one end of the outer side of the secondary air duct, and the adjustment block is provided with a chamber.

[0007] Preferably, the adjusting block is rotatably connected with a rotating shaft along its center position, and a positioning block is fixedly connected in the adjusting block chamber, and the rotating shaft is rotatably connected with the center position of the positioning block.

[0008] Preferably, the rotating shaft of each adjusting assembly penetrates into the secondary air duct, passes through the fixed partition, extends into the corresponding fixed partition slot, and is plugged and fixed with the corresponding external movable partition.

[0009] Preferably: several adjustment blocks of the adjustment components are distributed in a ring along the outer side of the secondary air duct, and the adjustment block of the oblique adjustment component is fixedly installed on the outer side of the secondary air duct between the adjustment blocks of two adjacent adjustment components, the rotating shaft of the oblique adjustment component passes through the secondary air duct, the fixed partition plate, and the auxiliary air duct rotation setting in sequence, and the rotating shaft of the oblique adjustment component is plugged and fixed to the inner movable plate at one end away from its adjustment block.

[0010] Preferably: the oblique adjustment assembly and the adjustment block of each adjustment assembly are respectively fixedly connected with four mutually perpendicular positioning cross bars on the outside of one end away from the secondary air duct, and each rotating shaft extends to the outside of the adjustment block away from one end of the secondary air duct and is fixedly connected with a bottom block.

[0011] Preferably, one end of each bottom block is fixedly connected to an adjustment rod arranged parallel to each positioning cross rod.

[0012] Preferably: each of the adjusting rods and each positioning cross bar is respectively provided with a fixing screw hole which cooperates with the thread of the limiting screw, and each adjusting rod is fixedly connected with a shift block at one end away from the bottom block, the secondary air blade angle of the burner is 0-45°, and each limiting screw is respectively arranged perpendicular to the positioning cross bar.

[0013] Compared with the prior art, the present invention has the following beneficial effects:

[0014] When the boiler of the present invention is running at ultra-low load, the staff can turn the dial block of the adjustment assembly to rotate the adjustment rod and drive the bottom block to rotate, so that the rotating shaft can rotate, and further the outer movable partition can rotate, and two of the positioning cross bars arranged opposite to each other are arranged to be perpendicular to the fixed partition, so that when the adjustment rod rotates with the bottom block to the bottom end of the positioning cross bar perpendicular to the fixed partition, the adjustment rod is fixed to the corresponding positioning cross bar by the limit screw, and the outer movable partition is perpendicular to the fixed partition, and then the rotating shaft of the oblique adjustment assembly is driven by the same operation process to set the inner movable plate parallel to the fixed partition, so that the inner side of the auxiliary air duct is a closed structure, and the secondary air can only be blown into the furnace from the area between the secondary air duct and the auxiliary air duct, so as to ensure that the secondary air burner can be used when the boiler is running at ultra-low load. If it continues to be put into use, it can play the normal role of the secondary air burner, improve the burnout rate, and ensure the combustion stability of the boiler. Conversely, with the same operation, the outer movable partition and the fixed partition are adjusted to be parallel to each other by rotating the rotating shaft of the adjusting component, and the inner movable plate is driven by the rotating shaft of the inclined adjusting component to rotate the vertical position of the fixed partition. Then, the area between the secondary air duct and the auxiliary air duct is a closed structure, and the secondary air can only be blown into the furnace from the inside of the auxiliary air duct; when the load is medium and high, the outer movable partition and the fixed partition are adjusted to be perpendicular to each other by rotating the rotating shaft of the adjusting component, and the inner movable plate is driven by the rotating shaft of the inclined adjusting component to rotate to a vertical position with the fixed partition. Then, the secondary air can be blown into the furnace from the inside of the auxiliary air duct and the area between the secondary air duct and the auxiliary air duct at the same time, without affecting the use effect of the secondary air at medium and high loads. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a structural schematic diagram of the present invention;

[0016] Figure 2 This is an enlarged schematic diagram of the structure at A of the present invention;

[0017] Figure 3 It is a side view structural schematic diagram of the present invention;

[0018] Figure 4 This is a schematic diagram of the structure of Example 2;

[0019] Figure 5 This is a structural schematic diagram of Example 3;

[0020] Figure 6This is a schematic diagram of the structure of Example 4;

[0021] Figure 7 This is a schematic diagram of the structure of Example 5;

[0022] Figure 8 This is a structural schematic diagram of Example 6.

[0023] In the figure: 1. secondary air duct; 2. auxiliary air duct; 3. adjustment assembly; 4. partition assembly; 5. inner movable plate; 6. oblique adjustment assembly; 31. adjustment block; 32. rotating shaft; 33. positioning block; 34. bottom block; 35. adjustment rod; 36. shift block; 37. positioning cross bar; 38. limiting screw; 41. fixed partition; 42. outer movable partition. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] Example 1

[0026] See also Figure 1-Figure 3 The figure shows a new type of strong penetrating flow structure secondary air burner suitable for a circulating fluidized bed boiler, including a secondary air duct 1, an auxiliary air duct 2 is fixedly arranged inside the secondary air duct 1, and one end of the secondary air duct 1 and the auxiliary air duct 2 are respectively fixedly connected to one end of the inner wall of the boiler, an adjustment component 3 is fixedly installed on the outside of the secondary air duct 1, and a partition component 4 is fixedly installed in the annular area surrounded by the inner side of the secondary air duct 1 and the outer side of the auxiliary air duct 2, an inner movable plate 5 is rotatably connected inside the auxiliary air duct 2, and an oblique adjustment component 6 fixedly connected to one end of the inner movable plate 5 is fixedly installed on the outer wall of the secondary air duct 1.

[0027] In this embodiment, the oblique adjustment component 6 and the adjustment component 3 both include an adjustment block 31 fixedly connected to one end of the outer side of the secondary air duct 1, and the adjustment block 31 has a chamber, and the adjustment block 31 is rotatably connected along its center position with a rotating shaft 32, and a positioning block 33 is fixedly connected in the chamber of the adjustment block 31, and the rotating shaft 32 is rotatably connected with the center position of the positioning block 33; the partition component 4 includes a fixed partition plate 41 arranged between the secondary air duct 1 and the auxiliary air duct 2, and the fixed partition plate 41 is an annular structure, the outer and inner sides of the fixed partition plate 41 are respectively fixedly connected to the inner wall of the secondary air duct 1 and the outer side of the auxiliary air duct 2, and the surface of the fixed partition plate 41 is provided with a through groove, and the through groove of the fixed partition plate 41 is provided with an external movable partition plate 42 whose shape is adapted thereto, and the external movable partition plate 42 is in smooth contact with the inner wall of the through groove corresponding to the fixed partition plate 41.

[0028] Furthermore, the rotating shaft 32 of the adjusting assembly 3 penetrates into the secondary air duct 1, passes through the fixed partition 41, extends into the corresponding through groove of the fixed partition 41, and is plugged and fixed with the corresponding outer movable partition 42; wherein the rotating shaft 32 can rotate freely;

[0029] The adjusting block 31 of the adjusting assembly 3 is fixedly mounted on the outside of the air duct 1, and the adjusting block 31 of the oblique adjusting assembly 6 is fixedly mounted on the outside of the secondary air duct 1 on one side of the adjusting block 31 of the adjusting assembly 3, and the rotating shaft 32 of the oblique adjusting assembly 6 passes through the secondary air duct 1, the fixed partition plate 41 and the auxiliary air duct 2 in sequence for rotation, and the rotating shaft 32 of the oblique adjusting assembly 6 is plugged and fixed to the inner movable plate 5 at one end away from its adjusting block 31.

[0030] Furthermore, the outer side of the adjusting block 31 of the oblique adjustment component 6 and the adjustment component 3 is respectively fixedly connected with four mutually perpendicular positioning cross bars 37, and the rotating shaft 32 extends to the outer side of the adjusting block 31 away from the end of the secondary air duct 1 and is fixedly connected with the bottom block 34, one end of the bottom block 34 is fixedly connected with an adjusting rod 35 arranged parallel to the positioning cross bar 37, the adjusting rod 35 and the positioning cross bar 37 are respectively provided with fixing screw holes threadedly matched with the limiting screw 38, and the adjusting rod 35 is fixedly connected with a shift block 36 at one end away from the bottom block 34, and the limiting screws 38 are respectively arranged perpendicular to the positioning cross bar 37. At this time, the outer movable partition 42 and the inner movable plate 5 are both in a closed state.

[0031] Example 2

[0032] See also Figure 4 In this embodiment, the number of adjustment components 3 and external movable partitions 42 is two, and they are symmetrically distributed along the two sides of the secondary air duct 1. By providing two adjustment components 3 and external movable partitions 42, the problem of being unable to adjust when one of the external movable partitions 42 fails can be avoided. At the same time, providing two external movable partitions 42 can also increase the adjustment range of the air volume. Figure 4 It is shown that at this time, the outer movable partition 42 and the inner movable panel 5 are both in a closed state.

[0033] Example 3

[0034] See also Figure 5 In this embodiment, the number of the adjustment components 3 and the outer movable partition 42 is set to four, and they are distributed in a ring shape along the outer side of the secondary air duct 1. By providing four adjustment components 3 and the outer movable partition 42, the adjustment range of the secondary air volume is further increased, so that the operation of the adjustment process has more options. Figure 5 It is shown that at this time, the outer movable partition 42 and the inner movable panel 5 are both in a closed state.

[0035] Example 4

[0036] See also Figure 6 In this embodiment, the shift block 36 of the oblique adjustment component 6 drives the adjustment rod 35 to rotate 90°. At this time, each outer movable partition 42 is still in a closed state, while the inner movable plate 5 is in an open state. When the boiler is running at ultra-low load, the outer movable partition 42 is adjusted by rotating the rotating shaft 32 of the adjustment component 3 to close the through groove on the fixed partition 41, and the rotating shaft 32 of the oblique adjustment component 6 drives the inner movable plate 5 to rotate to a vertical position with the fixed partition 41, then the area between the secondary air duct 1 and the auxiliary air duct 2 is a closed structure, and the secondary air can only be blown into the furnace from the inside of the auxiliary air duct 2.

[0037] Example 5

[0038] See also Figure 7 The staff member turns the dial block 36 of each adjustment component 3 to rotate the adjustment rod 35 and drive the bottom block 34 to rotate, so that the rotating shaft 32 can rotate, and further the outer movable partition 42 can rotate, and the two oppositely arranged positioning cross bars 37 are set to be perpendicular to each other with the fixed partition 41, so that when the adjustment rod 35 rotates with the bottom block 34 to the bottom end of the positioning cross bar 37 perpendicular to the fixed partition 41, the adjustment rod 35 is fixed to the corresponding positioning cross bar 37 by the limit screw 38. At this time, the outer movable partition 42 is perpendicular to the fixed partition 41, and then the rotating shaft 32 of the inclined adjustment component 6 drives the inner movable plate 5 to be set parallel to the fixed partition 41 in the same operation process, then the inner side of the auxiliary air duct 2 is a closed structure, and the secondary air can only be blown into the furnace from the area between the secondary air duct 1 and the auxiliary air duct 2, ensuring that the secondary air burner can continue to be used when the boiler is running at ultra-low load, which can play the normal role of the secondary air burner, improve the burnout rate, and ensure the combustion stability of the boiler.

[0039] Example 6

[0040] See also Figure 8 In this embodiment, when the load is medium or high, the outer movable partition 42 and the fixed partition 41 are adjusted to be perpendicular to each other by rotating the rotating shaft 32 of the adjusting component 3, and the rotating shaft 32 of the inclined adjusting component 6 is adjusted to drive the inner movable plate 5 to rotate to a perpendicular position with the fixed partition 41, so that the secondary air can be blown into the furnace from the inside of the auxiliary air duct 2 and the area between the secondary air duct 1 and the auxiliary air duct 2 at the same time, without affecting the use effect of the secondary air at medium or high loads.

[0041] Furthermore, for inferior coal with Vdaf≤15%, the coal is not easy to burn, and the required secondary air stiffness is relatively large. The secondary air blade angle is set to 0-25°, the secondary air flow area is small, and the secondary air speed is high, thereby ensuring the penetration ability of the secondary air; for sub-bituminous coal with 16%≤Vdaf≤26%, the coal quality burns poorly, and the secondary air blade angle is set to 25-30°, ensuring a small secondary air flow area, thereby ensuring the penetration ability of the secondary air; for bituminous coal with 27%≤Vdaf≤40%, the coal quality is easier to burn, the secondary air speed is appropriately reduced, a larger secondary air flow area can be appropriately retained, and the secondary air blade angle is set to 30-40°; for lignite with Vdaf≥40%, the coal quality is easy to burn, the secondary air speed requirement is low, and the secondary air blade angle is set to 40-45°, which can achieve the secondary air meeting the stable operation requirements when operating at ultra-low load when burning different coal qualities.

[0042] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0043] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A novel strong penetrating flow structure secondary air burner suitable for a circulating fluidized bed boiler, comprising a secondary air duct (1), characterized in that: An auxiliary air duct (2) is fixedly arranged inside the secondary air duct (1), and one end of the secondary air duct (1) and the auxiliary air duct (2) are respectively fixedly connected to one end of the inner wall of the boiler, a plurality of adjustment components (3) are fixedly installed on the outer side of the secondary air duct (1), and a partition component (4) is fixedly installed in the annular area surrounded by the inner side of the secondary air duct (1) and the outer side of the auxiliary air duct (2), an inner movable plate (5) is rotatably connected inside the auxiliary air duct (2), and an oblique adjustment component (6) fixedly connected to one end of the inner movable plate (5) is fixedly installed on the outer wall of the secondary air duct (1); The partition assembly (4) comprises a fixed partition (41) arranged between the secondary air duct (1) and the auxiliary air duct (2), and the fixed partition (41) is an annular structure, the outer side and the inner side of the fixed partition (41) are respectively fixedly connected to the inner wall of the secondary air duct (1) and the outer side of the auxiliary air duct (2), and a plurality of through grooves are formed on the surface of the fixed partition (41); Each through slot of the fixed partition (41) is provided with an outer movable partition (42) whose shape matches that of the fixed partition, and each outer movable partition (42) is in smooth contact with the inner wall of the through slot corresponding to the fixed partition (41).

2. According to claim 1, a novel strong penetrating flow structure secondary air burner suitable for a circulating fluidized bed boiler is characterized by: The oblique adjustment component (6) and each adjustment component (3) comprise an adjustment block (31) fixedly connected to one end of the outer side of the secondary air duct (1), and the adjustment block (31) is provided with a chamber.

3. According to claim 2, a novel strong penetrating flow structure secondary air burner suitable for a circulating fluidized bed boiler is characterized by: The adjusting block (31) is rotatably connected to a rotating shaft (32) along its center position, and a positioning block (33) is fixedly connected in the chamber of the adjusting block (31), and the rotating shaft (32) is rotatably connected to the center position of the positioning block (33).

4. The novel strong penetrating flow structure secondary air burner suitable for circulating fluidized bed boiler according to claim 3 is characterized by: The rotating shaft (32) of each adjusting assembly (3) penetrates into the secondary air duct (1), passes through the fixed partition (41), extends into the corresponding through groove of the fixed partition (41), and is plugged and fixed to the corresponding outer movable partition (42).

5. The novel strong penetrating flow structure secondary air burner suitable for circulating fluidized bed boiler according to claim 4 is characterized in that: The adjusting blocks (31) of the plurality of adjusting assemblies (3) are distributed in a ring shape along the outer side of the secondary air duct (1), and the adjusting block (31) of the oblique adjusting assembly (6) is fixedly mounted on the outer side of the secondary air duct (1) between the adjusting blocks (31) of two adjacent adjusting assemblies (3). The rotating shaft (32) of the oblique adjusting assembly (6) sequentially penetrates the secondary air duct (1), the fixed partition plate (41), and the auxiliary air duct (2) for rotation, and the rotating shaft (32) of the oblique adjusting assembly (6) is plugged and fixed to the inner movable plate (5) at one end away from the adjusting block (31).

6. The novel strong penetrating flow structure secondary air burner suitable for circulating fluidized bed boiler according to claim 5 is characterized by: The oblique adjustment component (6) and the adjustment block (31) of each adjustment component (3) are respectively fixedly connected to four mutually perpendicular positioning cross bars (37) at the outer side of one end away from the secondary air duct (1), and each rotating shaft (32) extends to the outer side of the adjustment block (31) at one end away from the secondary air duct (1) and is fixedly connected to a bottom block (34).

7. The novel strong penetrating flow structure secondary air burner suitable for circulating fluidized bed boiler according to claim 6 is characterized by: One end of each bottom block (34) is fixedly connected to an adjustment rod (35) arranged parallel to each positioning cross rod (37).

8. The novel strong penetrating flow structure secondary air burner suitable for circulating fluidized bed boiler according to claim 7 is characterized by: Each of the adjusting rods (35) and each of the positioning cross bars (37) is provided with a fixing screw hole threadedly matched with a limiting screw (38), and one end of each adjusting rod (35) away from the bottom block (34) is fixedly connected to a shifting block (36), the secondary air blade angle of the burner is 0-45°, and each limiting screw (38) is vertically arranged with respect to the positioning cross bar (37).

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