Air distribution system of biomass boiler

Abstract

An air distribution system of a biomass boiler comprises a draught fan and an air pipe which are arranged outside the biomass boiler, secondary air inlets are formed in the two opposite sides of the biomass boiler, air distribution units corresponding to the secondary air inlets are arranged in the biomass boiler, the air distribution units are communicated with the draught fan through the air pipe, and the end, close to the air distribution units, of the air pipe is a bent pipe section. The air distribution unit comprises an air distributor, an air distribution plate arranged in the air distributor and an air guide connecting plate, the air distributor is installed on the inner wall of the biomass boiler in the horizontal direction, the air distribution plate is arranged in the middle of the air distributor in the horizontal direction, and an air blowing hole set is formed in the side, away from the inner wall of the biomass boiler, of the air distributor. The fan conveys gas for sufficient combustion of fuel to the air distributor of the air distribution unit, the joint of the air distributor and the air pipe is of a bent pipe section structure, and compared with a right-angle pipe, the bent pipe section can relieve impact of air generated by the fan on the joint of the air pipe and the air distributor, so that air flow is smoother, and turbulent flow and pressure drop are reduced.

Description

Technical Field

[0001] This utility model relates to the field of biomass boiler technology, specifically to an air distribution system for a biomass boiler. Background Technology

[0002] Modern biomass boilers generally use bottom air supply to provide oxygen for the combustion of biomass fuel on the grate, promoting stable combustion on the grate. In order to further provide sufficient oxygen to biomass fuel, a "bottom + side" coordinated air distribution mode is adopted to provide sufficient oxygen to biomass fuel combustion from multiple directions and optimize the combustion zone.

[0003] Existing biomass boiler air distribution devices generally include air ducts installed outside the biomass filter and air distributors installed inside the biomass boiler. The air distributors are detachably connected to the air ducts via pins, facilitating future replacement. The pins are vertically inserted through the air distributors and air ducts. However, vibration of the air ducts and air distributors during operation is unavoidable. The air distributors and air ducts cause the pins to vibrate. Over long-term use, the pins may detach from the connection points of the air distributors and air ducts, affecting the stable connection between them. Furthermore, the connection between the air ducts and air distributors in existing technologies is at a right angle. After the airflow impacts the duct wall, its kinetic energy is converted into turbulence, resulting in pressure loss and affecting the blowing effect. Utility Model Content

[0004] To address the technical problems existing in the background art, this utility model provides an air distribution system for a biomass boiler.

[0005] The technical solution of this utility model is as follows:

[0006] An air distribution system for a biomass boiler includes a fan and an air duct installed outside the biomass boiler. The biomass boiler has secondary air inlets on opposite sides. An air distribution unit corresponding to the secondary air inlets is installed inside the biomass boiler. The air distribution unit is connected to the fan through an air duct. The end of the air duct near the air distribution unit is a bend.

[0007] The air distribution unit includes an air distributor, an air distribution plate installed inside the air distributor, and an air guide connecting plate. The air distributor is installed horizontally on the inner wall of the biomass boiler, and the air distribution plate is installed horizontally in the middle of the air distributor. An air blowing hole group is provided on the inner wall side of the air distributor away from the biomass boiler.

[0008] The air distributor has an air inlet on one side that is compatible with the secondary air inlet. One end of the air guide plate is connected to the air distribution plate, and the other end is detachably connected to the bend section.

[0009] Preferably, the inner wall of the bend section is provided with an arc-shaped slot in the horizontal direction, the air guide connecting plate is adapted to the arc-shaped slot on the side near the bend section, the air guide connecting plate is inserted into the arc-shaped slot and connected by a connector.

[0010] Furthermore, the axis of the connector is horizontal, and the connector passes through the bend section, the arc-shaped slot and connects to the air guide plate in sequence.

[0011] The structure that allows the air guide connecting plate and the connector to be stably connected without occupying the internal space of the air duct is as follows: the air guide connecting plate has a threaded hole in the middle of the horizontal direction that is compatible with the connector. The connector can be connected in the middle of the air guide connecting plate without occupying the internal space of the air duct or affecting the flow rate of the air inside the air duct.

[0012] Furthermore, the arc-shaped slot is located in the middle of the bend section.

[0013] The specific structure of the air blower group is as follows: the air blower group includes an upper air blower group located above the air distribution plate and a lower air blower group located below the air distribution plate.

[0014] Furthermore, the upper air blowing hole group includes multiple upper air blowing holes, and the lower air blowing hole group includes multiple lower air blowing holes, with the diameter of the upper air blowing holes being smaller than the diameter of the lower air blowing holes.

[0015] To facilitate the stable installation of the air distributor inside the biomass boiler with the connecting parts, a support is provided below the air distributor. The support is connected to the inner wall of the biomass boiler and provides support for the air distributor.

[0016] The beneficial effects of this utility model are as follows:

[0017] The biomass boiler has two symmetrical air distribution units on both sides. The two air distribution units are connected to the external fan through air ducts. The fan delivers gas to the air distributor of the air distribution unit to ensure complete combustion of fuel. The connection between the air distributor and the air duct is a bend. Compared with a right-angle pipe, the bend can reduce the impact of the air generated by the fan on the connection between the air duct and the air distributor, making the air flow smoother and reducing turbulence and pressure drop.

[0018] The air distributor can be stably connected to the air duct through the air guide connecting plate, and together with the support components, it plays the role of stably supporting the air distributor inside the biomass boiler.

[0019] The air guide plate is set horizontally, and the air guide plate and the air distribution plate are on the same horizontal plane, which greatly reduces the obstruction of air flow by the air guide plate in the air duct. In addition, the air guide plate and the air distribution plate can distribute the air delivered by the air duct to the upper and lower directions of the air distributor, increasing the blowing range of the air distributor's blowing holes.

[0020] The diameter of the upper air blowing hole is smaller than that of the lower air blowing hole, which can deliver air flow from bottom to top and from large to small into the biomass boiler. The lower air blowing hole has a larger diameter and a larger air volume, which meets the oxygen demand of the fuel drying and thermal decomposition stages.

[0021] The connector is located on the outside of the biomass boiler and can pass through the air duct to connect with the air guide plate, making it easy to disassemble the connector from the outside for replacing the air distributor. Attached Figure Description

[0022] In the attached diagram:

[0023] Figure 1 This is a partial top-view structural diagram;

[0024] Figure 2 This is a schematic diagram of a partial sectional view of the structure;

[0025] Figure 3 for Figure 2 Enlarged structural diagram at point A in the middle;

[0026] Figure 4 This is a schematic diagram of the first structure of the air distributor;

[0027] Figure 5 This is a schematic diagram of the second structure of the air distributor;

[0028] Figure 6 This is a schematic diagram of the bend section and the air guide connecting plate.

[0029] Figure 7 for Figure 6 Enlarged structural diagram at point B;

[0030] Figure 8 A schematic diagram of the internal structure of a biomass boiler;

[0031] The components represented by the various reference numerals in the diagram are:

[0032] 1. Biomass boiler; 101. Secondary air inlet; 2. Air duct; 201. Bend section; 2011. Arc-shaped slot; 3. Fan; 4. Air distributor; 5. Air distribution plate; 6. Air guide connecting plate; 601. Threaded hole; 7. Connector; 8. Upper air blowing hole; 9. Lower air blowing hole; 10. Support component. Detailed Implementation

[0033] See Figure 1 , Figure 2 and Figure 8 As shown, a biomass boiler air distribution system includes a fan 3 and an air duct 2 installed outside the biomass boiler 1. The bottom of the biomass boiler 1 is provided with a primary air inlet for supplying air at the bottom, which is the prior art. In this embodiment, a secondary air inlet 101 is provided on opposite sides of the biomass boiler 1, and an air distribution unit corresponding to the secondary air inlet 101 is provided inside the biomass boiler 1.

[0034] Both air distribution units are connected to the external fan 3 through duct 2. The end of duct 2 near the air distribution unit is a bend section 201, which is connected to the air inlet of the air distributor 4. Compared with a right-angle pipe, the bend section 201 can mitigate the impact of the air generated by the fan 3 on the connection between duct 2 and air distributor 4, making the air flow smoother and reducing turbulence and pressure drop.

[0035] See Figure 3 , Figure 4 , Figure 5 and Figure 6 As shown, the air distribution unit includes an air distributor 4, an air distribution plate 5 disposed within the air distributor 4, and an air guide connecting plate 6. The air distributor 4 is installed horizontally on the inner wall of the biomass boiler 1. The air distribution plate 5 is disposed horizontally in the middle of the air distributor 4. An air blowing hole group is provided on the inner wall side of the air distributor 4 away from the biomass boiler 1. An air inlet adapted to the secondary air inlet 101 is provided on one side of the air distributor 4. One end of the air guide connecting plate 6 is connected to the air distribution plate 5, and the other end is detachably connected to the bend section 201.

[0036] See Figure 6 and Figure 7 As shown, in this embodiment, the inner wall of the bend section 201 is provided with an arc-shaped slot 2011 along the horizontal direction, and the arc-shaped slot 2011 is located in the middle of the bend section 201. The air guide connecting plate 6 is adapted to the arc-shaped slot 2011 on the side near the bend section 201. The side of the air guide connecting plate 6 near the bend section 201 has an arc-shaped structure, which facilitates the insertion of the air guide connecting plate 6 into the arc-shaped slot 2011, and the connection is achieved by the connector 7, realizing the positioning and connection of the air guide connecting plate 6. The axis of the connector 7 is in the horizontal direction, and the connector 7 passes through the bend section 201 and the arc-shaped slot 2011 in sequence to connect with the air guide connecting plate 6.

[0037] In the above structure, the structure in which the air guide connecting plate 6 and the connector 7 can be stably connected without occupying the internal space of the air duct 2 is as follows: the air guide connecting plate 6 has a threaded hole 601 in the middle of the horizontal direction that is compatible with the connector 7. The connector 7 can be connected in the middle position of the air guide connecting plate 6, without occupying the internal space of the air duct 2, and without affecting the flow rate of the air flowing inside the air duct 2.

[0038] The air guide plate 6 is set horizontally, and the air guide plate 6 and the air distribution plate 5 are on the same horizontal plane, which greatly reduces the obstruction of air flow by the air guide plate 6 in the air duct 2. In addition, the air guide plate 6, together with the air distribution plate 5, can distribute the air delivered by the air duct 2 to the air distributor 4 in both the upper and lower directions, increasing the blowing range of the air distributor 4's blowing holes.

[0039] See Figure 4As shown, the specific structure of the air blowing hole group is as follows: the air blowing hole group includes an upper air blowing hole group 8 located above the air distribution plate 5 and a lower air blowing hole group 9 located below the air distribution plate 5. The upper air blowing hole group 8 includes multiple upper air blowing holes 8, which are arranged in a matrix along the length direction of the air distributor 4. The lower air blowing hole group 9 includes multiple lower air blowing holes 9, which are also arranged in a matrix along the length direction of the air distributor 4. The diameter of the upper air blowing holes 8 is smaller than that of the lower air blowing holes 9, which can deliver airflow from bottom to top, from the largest to the smallest, into the biomass boiler 1. The lower air blowing holes have a larger diameter and a larger air volume, which meets the oxygen demand in the fuel drying and thermal decomposition stages. The upper air blowing holes 8 have a smaller diameter and a relatively smaller air volume, which can better control the oxygen concentration in the combustion zone above the fuel and reduce the increase in nitrogen oxide content caused by excessive combustion.

[0040] To facilitate the stable installation of the air distributor 4 inside the biomass boiler 1 with the connector 7, a support 10 is provided below the air distributor 4. The support 10 is connected to the inner wall of the biomass boiler 1 and provides support for the air distributor 4. It is used in conjunction with the air guide plate 6.

Claims

1. An air distribution system for a biomass boiler, characterized in that The application relates to a biomass boiler (1) provided with a fan (3) and an air pipe (2) outside the biomass boiler (1), two secondary air inlets (101) are arranged on opposite sides of the biomass boiler (1), a wind distribution unit corresponding to the secondary air inlets (101) is arranged in the biomass boiler (1), the wind distribution unit is communicated with the fan (3) through the air pipe (2), and one end of the air pipe (2) close to the wind distribution unit is a bent pipe section (201). The wind distribution unit comprises a wind distributor (4), a wind distribution plate (5) arranged in the wind distributor (4) and a wind guide connecting plate (6), the wind distributor (4) is arranged on the inner wall of the biomass boiler (1) in the horizontal direction, the wind distribution plate (5) is arranged in the middle of the wind distributor (4) in the horizontal direction, and a plurality of air blowing holes are arranged on the side of the wind distributor (4) away from the inner wall of the biomass boiler (1). One side of the wind distributor (4) is provided with an air inlet matched with the secondary air inlet (101), one end of the wind guide connecting plate (6) is connected with the wind distribution plate (5), and the other end is detachably connected with the bent pipe section (201).

2. The air distribution system of a biomass boiler according to claim 1, characterized in that, An arc-shaped slot (2011) is arranged on the inner wall of the bent pipe section (201) in the horizontal direction, the side of the wind guide connecting plate (6) close to the bent pipe section (201) is matched with the arc-shaped slot (2011), the wind guide connecting plate (6) is inserted into the arc-shaped slot (2011) and is connected through a connecting piece (7).

3. The air distribution system of a biomass boiler according to claim 2, characterized in that The axis of the connecting piece (7) is in the horizontal direction, and the connecting piece (7) is connected with the wind guide connecting plate (6) in sequence through the bent pipe section (201) and the arc-shaped slot (2011).

4. The air distribution system of a biomass boiler according to claim 3, characterized in that A threaded hole (601) matched with the connecting piece (7) is arranged in the middle of the wind guide connecting plate (6) in the horizontal direction.

5. The air distribution system of a biomass boiler according to claim 3, characterized in that, The arc-shaped slot (2011) is located in the middle of the bent pipe section (201).

6. The air distribution system of a biomass boiler according to claim 1, characterized in that, The air blowing hole group comprises an upper air blowing hole (8) group located above the wind distribution plate (5) and a lower air blowing hole (9) group located below the wind distribution plate (5).

7. A biomass boiler air distribution system according to claim 6, wherein, The upper air blowing hole (8) group comprises a plurality of upper air blowing holes (8), the lower air blowing hole (9) group comprises a plurality of lower air blowing holes (9), and the aperture of the upper air blowing hole (8) is smaller than that of the lower air blowing hole (9).

8. The air distribution system of a biomass boiler according to claim 1, characterized in that, A supporting piece (10) is arranged below the wind distributor (4) and connected with the inner wall of the biomass boiler (1).

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