The central structure of a high-capacity vertical kiln

Abstract

The invention relates to a central structure of a high-capacity vertical kiln, which is arranged at the center of the vertical kiln; the structure comprises a central cylinder, an upper support assembly, a distributor and an annular discharging device; the central cylinder is composed of a main steel pipe, a cooling air duct, a swirl sheet and a refractory protective layer; the main steel pipe, the cooling air duct, the distributor and the annular discharging device are all coaxially arranged with the vertical kiln; the cooling air duct is arranged inside the main steel pipe, and a swirl sheet is arranged in the annular space between the cooling air duct and the main steel pipe; the invention arranges a central cylinder in the kiln chamber, so that the heating of the material in the kiln is more uniform; the central cylinder is cooled by cooling wind, a refractory protective layer is arranged on the outer side of the central cylinder, the upper end is supported by an upper support assembly, and a matching distributor is arranged, which can effectively prevent the impact of the material entering the kiln and the erosion of the high temperature in the kiln, and the overall structure is more stable.

Description

Technical Field

[0001] The invention relates to the technical field of vertical kilns, and in particular to a central structure of a vertical kiln with large output. Background Art

[0002] At present, industrial kilns are gradually developing in the direction of large-scale. With the continuous increase in the size of kilns, the design and use of vertical kilns with larger diameter circular kiln chambers have encountered some new problems and challenges. Since the internal space of the kiln chamber of the vertical kiln is large, when air is introduced along the circumference of the kiln, the distribution of air along the cross-section direction of the material in the kiln is very uneven. The fuel combustion in the center of the kiln and the heat exchange intensity between the gas and the material are worse than those near the kiln wall, resulting in uneven calcination of the raw materials, high fuel consumption and increased air consumption coefficient of the exhaust gas.

[0003] In order to reduce the deviation of airflow inside the kiln chamber of the vertical kiln, people try to set a cylinder in the center of the kiln chamber to occupy the material space. However, setting a cylinder in the center of the kiln chamber requires solving the following problems:

[0004] 1) Using only steel pipes as the support for the central cylinder is difficult to resist the high temperature at the center of the kiln chamber (the steel pipe is prone to softening and deformation);

[0005] 2) The vertical kiln unloads materials from the top of the kiln chamber. The materials falling from above will impact the central cylinder and its supporting structure. Long-term hard collision will eventually lead to the destruction of the central cylinder and its supporting structure;

[0006] 3) The height-to-diameter ratio of the central cylinder is above 12:1. If the upper and lower ends are not fixed properly, it is very easy to cause deviation or tilt problems.

[0007] The present invention focuses on solving the above problems, breaking through the bottleneck encountered in the process of vertical kiln development towards large-scale, and taking the design of large-diameter circular kiln chamber vertical kiln to a new level. Summary of the invention

[0008] The present invention provides a central structure of a high-capacity vertical kiln, in which a central cylinder is arranged in the kiln chamber, so that the materials in the kiln are heated more evenly; the central cylinder is cooled by cooling air, a refractory protective layer is arranged on the outer side of the central cylinder, the upper end is supported by an upper supporting assembly, and a matching material distributor is arranged, which can effectively prevent the impact of materials entering the kiln and the erosion of high temperature in the kiln, and the overall structure is more stable.

[0009] In order to achieve the above object, the present invention adopts the following technical solutions:

[0010] The central structure of a high-capacity vertical kiln is arranged at the center of the vertical kiln; it comprises a central cylinder, an upper support assembly, a distributor and an annular discharging device; the central cylinder consists of a main steel pipe, a cooling air duct, a swirl plate and a refractory protective layer; the main steel pipe, the cooling air duct, the distributor and the annular discharging device are all arranged coaxially with the vertical kiln; the cooling air duct is arranged inside the main steel pipe, and a swirl plate is arranged in the annular space between the cooling air duct and the main steel pipe; the upper end of the main steel pipe extends to the top of the cooling air duct, and a baffle is arranged above the cooling air duct in the main steel pipe; the lower end of the cooling air duct extends to the bottom of the main steel pipe; the top end of the main steel pipe is connected to the inner wall of the vertical kiln through the upper support assembly, the distributor is arranged above the upper support assembly, and the bottom of the main steel pipe is provided with an annular discharging device; a cooling air inlet is arranged at the bottom end of the cooling air duct; and a refractory protective layer is arranged outside the main steel pipe.

[0011] The main steel pipe and the cooling air duct are both made of corrosion-resistant seamless steel pipes.

[0012] The swirl sheet is composed of a plurality of spiral blades which are spirally arranged along the axial direction of the cooling air duct.

[0013] The upper support assembly consists of an annular support seat, a support beam and a support seat; the annular support seat is arranged on the outside of the main steel pipe, and multiple support seats are evenly arranged circumferentially at corresponding heights on the inner wall of the vertical kiln, and each support seat is connected to the annular support seat through a corresponding support beam; each support beam is arranged along the radial direction of the main steel pipe.

[0014] The distributor is a frustum-shaped distributor; it consists of a distributor body and a plurality of shock-absorbing rings; the distributor body is a frustum-shaped structure consisting of a conical cylinder and a top plate, and the bottom diameter of the conical cylinder is larger than the top diameter; a plurality of shock-absorbing rings are arranged on the outside of the conical cylinder along the height direction; the shock-absorbing ring is made of annular steel plate, which is arranged vertically, and the bottom end of the annular steel plate is fixedly connected to the outer wall of the conical cylinder, and a plurality of reinforcing rib plates are arranged between the inner side of the annular steel plate and the outer wall of the conical cylinder.

[0015] The annular discharging device consists of an annular bottom plate and an annular enclosure; the annular bottom plate is fixedly connected to the bottom end of the main steel pipe, and multiple layers of trumpet-shaped annular enclosures are arranged on the outer side of the annular bottom plate, and exhaust ports are arranged between each layer of the annular enclosures.

[0016] The refractory protective layer is built with refractory bricks, and the refractory bricks are built in at least three layers from the inside to the outside, and the refractory bricks in the outermost layer have an interlocking structure.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] 1) The materials inside the kiln chamber are distributed between the outer wall of the central cylinder and the inner wall of the kiln chamber, so that the materials in the kiln chamber can be evenly heated along the cross-sectional direction, which greatly reduces the raw burning rate and over-burning rate of the finished product and improves the product quality;

[0019] 2) The central cylinder uses the main steel pipe as the main support, and the outside of the central cylinder is provided with a refractory protective layer. Its weight is mainly concentrated in the center of the kiln chamber of the vertical kiln. Large vertical kilns are mostly slender and tall. This structure is conducive to a more stable center of gravity of the vertical kiln;

[0020] 3) The upper end of the central cylinder is supported by an upper support assembly, and a new type of distributor is installed on the upper end, which can effectively reduce the impact on the upper support part and the central cylinder and extend the service life of the central cylinder;

[0021] 4) The central cylinder adopts an air-cooling structure to prevent the main steel pipe from softening and deforming under the high temperature in the kiln; the cooling air after heat exchange with the main steel pipe can enter the kiln from the bottom of the kiln chamber as combustion air to participate in the combustion in the kiln, thereby increasing the temperature of the combustion air in the kiln and thus playing a role in energy saving. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the central structure of a high-capacity vertical kiln described in the present invention.

[0023] Figure 2 It is a partial enlarged view of the central structure of a high-capacity vertical kiln described in the present invention.

[0024] Figure 3 It is a schematic diagram (partial) of the arrangement of the swirl blades described in the embodiment of the present invention.

[0025] In the figure: 1. Main steel pipe 2. Cooling air duct 3. Swirl sheet 4. Refractory protective layer 5. Annular support seat 6. Support beam 7. Support seat 8. Distributor 9. Vertical kiln 10. Annular discharge device DETAILED DESCRIPTION

[0026] The specific implementation of the present invention will be further described below in conjunction with the accompanying drawings:

[0027] like Figure 1 , Figure 2As shown, the central structure of a high-capacity vertical kiln described in the present invention is arranged at the center of the vertical kiln; it includes a central cylinder, an upper support assembly, a distributor 8 and an annular discharging device 10; the central cylinder is composed of a main steel pipe 1, a cooling air duct 2, a swirl sheet 3 and a refractory protective layer 4; the main steel pipe 1, the cooling air duct 2, the distributor 8 and the annular discharging device 10 are all arranged coaxially with the vertical kiln 9; the cooling air duct 2 is arranged inside the main steel pipe 1, and the annular space between the cooling air duct 2 and the main steel pipe 1 A swirl sheet 3 is arranged in the space; the upper end of the main steel pipe 1 extends to the top of the cooling air duct 2, and a baffle is arranged above the cooling air duct 2 in the main steel pipe 1; the lower end of the cooling air duct 2 extends to the bottom of the main steel pipe 1; the top of the main steel pipe 1 is connected to the inner wall of the vertical kiln 9 through the upper support assembly, the distributor 8 is arranged above the upper support assembly, and the bottom of the main steel pipe 1 is provided with an annular discharging device 10; the bottom end of the cooling air duct 2 is provided with a cooling air inlet; the outside of the main steel pipe 1 is provided with a refractory protective layer 4.

[0028] The main steel pipe 1 and the cooling air duct 2 are both made of corrosion-resistant seamless steel pipes.

[0029] like Figure 3 As shown, the swirl plate 3 is composed of a plurality of spiral blades which are spirally arranged along the axial direction of the cooling air duct 2 .

[0030] like Figure 2 As shown, the upper support assembly consists of an annular support seat 5, a support beam 6 and a support seat 7; the annular support seat 5 is arranged on the outside of the main steel pipe 1, and multiple support seats 7 are evenly arranged on the inner wall of the vertical kiln 9 at corresponding heights along the circumferential direction, and each support seat 7 is connected to the annular support seat 5 through a corresponding support beam 6; each support beam 6 is arranged along the radial direction of the main steel pipe 1.

[0031] The distributor 8 is a truncated cone-shaped distributor; it is composed of a distributor body and a plurality of shock-absorbing rings; the distributor body is a truncated cone-shaped structure composed of a conical cylinder and a top plate, and the bottom diameter of the conical cylinder is larger than the top diameter; a plurality of shock-absorbing rings are arranged on the outside of the conical cylinder along the height direction; the shock-absorbing ring is made of annular steel plate, which is vertically arranged, and the bottom end of the annular steel plate is fixedly connected to the outer wall of the conical cylinder, and a plurality of reinforcing rib plates are arranged between the inner side of the annular steel plate and the outer wall of the conical cylinder.

[0032] The annular discharging device 10 is composed of an annular bottom plate and an annular enclosure; the annular bottom plate is fixedly connected to the bottom end of the main steel pipe 1, and multiple layers of trumpet-shaped annular enclosures are arranged on the outer side of the annular bottom plate, and exhaust ports are arranged between each layer of the annular enclosures.

[0033] The refractory protective layer 4 is built of refractory bricks, and the refractory bricks are built in at least three layers from the inside to the outside, and the refractory bricks of the outermost layer have an interlocking structure.

[0034] The following embodiments are implemented on the premise of the technical solution of the present invention, and provide detailed implementation methods and specific operation processes, but the protection scope of the present invention is not limited to the following embodiments.

[0035] [Example]

[0036] like Figure 1-Figure 3 As shown, in this embodiment, the central structure of the vertical kiln includes a main steel pipe 1, a cooling air duct 2, a swirl sheet 3, a refractory protective layer 4, an annular support seat 5, a support beam 6, a support seat 7, a distributor 8 and an annular discharge device 10.

[0037] The cooling air duct 2 is located at the innermost part of the central cylinder, and the main steel pipe 1 is sleeved on the outer side of the cooling air duct 2. Between the cooling air duct 2 and the main steel pipe 1, four swirl sheets 3 made of steel plates are welded from top to bottom along the spiral line direction.

[0038] The lower end of the main steel pipe 1 is welded and fixed to the annular discharging device 10, and an annular support 5 is arranged on the outer side of the upper end of the main steel pipe 1. The support beam 6 is composed of 8 H-shaped steels, and one end of the support beam 6 close to the kiln shell of the vertical kiln 9 is hinged and fixed to the support seat 7 on the inner wall of the kiln shell. When the support beam 6 made of H-shaped steel is installed, the notch on one side faces upward, and its purpose is to receive the material falling from the kiln top, so that part of the material is stored in the notch of the H-shaped steel to form a material cushion, so as to prevent the impact force of the falling material from directly acting on the support beam 6.

[0039] A truncated cone-shaped distributor 8 made of steel plate is installed above the upper support assembly. Three layers of shock-absorbing rings are welded on the outer circumference of the conical cylinder, and a small amount of material can be stored in the space between the shock-absorbing ring and the conical cylinder; when feeding from the kiln top, the falling material first contacts the material in the shock-absorbing ring to prevent the impact force of the falling material from directly acting on the distributor 8.

[0040] The central cylinder uses the main steel pipe 1 as the main support to ensure the strength of the overall structure. Three layers of refractory bricks are built on the outside of the main steel pipe 1 to protect the main steel pipe 1 from melting and deformation due to the high temperature inside the kiln chamber. The outermost layer of refractory bricks are built in a way that they interlock with each other to form an interlocking structure. After the masonry is completed, a stable overall structure is formed to prevent the refractory bricks from falling off due to factors such as material scouring.

[0041] The interior of the central cylinder is prone to heat accumulation, causing the main steel pipe 1 to deform. In order to solve this problem, the present invention sets an air cooling structure inside the central cylinder. The cooling air passes through the cooling air duct 2 from bottom to top, and performs a heat exchange with the hot air inside the main steel pipe 1 during the movement. The heated cooling air enters the annular space between the cooling air duct 2 and the main steel pipe 1 from the outlet at the top of the cooling air duct 2 (a baffle is provided above the outlet to turn the airflow direction back downward). The cooling air is in direct contact with the inner wall of the main steel pipe 1, achieving secondary heat exchange with the inner wall of the main steel pipe 1; thereby achieving the purpose of cooling the central cylinder. The cooling air after heat exchange enters the kiln through the annular discharge device 10 at the bottom of the kiln chamber, and can be used as combustion-supporting air, participating in the combustion in the kiln, increasing the temperature of the combustion-supporting air in the kiln, and thus playing a role in energy saving.

[0042] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A central structure of a high-capacity vertical kiln, located at the center of the vertical kiln; characterized in that: The invention comprises a central cylinder, an upper support assembly, a distributor and an annular discharging device; the central cylinder is composed of a main steel pipe, a cooling air duct, a swirl plate and a refractory protective layer; the main steel pipe, the cooling air duct, the distributor and the annular discharging device are all arranged coaxially with the vertical kiln; an air cooling structure is arranged inside the central cylinder, and cooling air passes through the cooling air duct from bottom to top; the cooling air duct is arranged inside the main steel pipe, and a swirl plate is arranged in the annular space between the cooling air duct and the main steel pipe; the upper end of the main steel pipe extends to the top of the cooling air duct, and a baffle is arranged above the cooling air duct in the main steel pipe; the lower end of the cooling air duct extends to the bottom of the main steel pipe; the top of the main steel pipe passes through the upper support assembly. The support assembly is connected to the inner wall of the vertical kiln, and a distributor is arranged above the upper support assembly. The distributor is a truncated cone-shaped distributor; it is composed of a distributor body and a plurality of shock-absorbing rings; the distributor body is a truncated cone-shaped structure composed of a conical cylinder and a top plate, and the bottom diameter of the conical cylinder is larger than the top diameter; a plurality of shock-absorbing rings are arranged on the outside of the conical cylinder along the height direction; the shock-absorbing ring is made of annular steel plate, which is vertically arranged, and the bottom end of the annular steel plate is fixedly connected to the outer wall of the conical cylinder, and a plurality of reinforcing rib plates are arranged between the inner side of the annular steel plate and the outer wall of the conical cylinder; an annular discharge device is arranged at the bottom of the main steel pipe; a cooling air inlet is arranged at the bottom end of the cooling air duct; a refractory protective layer is arranged on the outside of the main steel pipe.

2. The central structure of a high-capacity vertical kiln according to claim 1, characterized in that: The main steel pipe and the cooling air duct are both made of corrosion-resistant seamless steel pipes.

3. The central structure of a high-capacity vertical kiln according to claim 1, characterized in that: The swirl sheet is composed of a plurality of spiral blades which are spirally arranged along the axial direction of the cooling air duct.

4. The central structure of a high-capacity vertical kiln according to claim 1, characterized in that: The upper support assembly consists of an annular support seat, a support beam and a support seat; the annular support seat is arranged on the outside of the main steel pipe, and multiple support seats are evenly arranged circumferentially at corresponding heights on the inner wall of the vertical kiln, and each support seat is connected to the annular support seat through a corresponding support beam; each support beam is arranged along the radial direction of the main steel pipe.

5. The central structure of a high-capacity vertical kiln according to claim 1, characterized in that: The annular discharging device consists of an annular bottom plate and an annular enclosure; the annular bottom plate is fixedly connected to the bottom end of the main steel pipe, and multiple layers of trumpet-shaped annular enclosures are arranged on the outer side of the annular bottom plate, and exhaust ports are arranged between each layer of the annular enclosures.

6. The central structure of a high-capacity vertical kiln according to claim 1, characterized in that: The refractory protective layer is built with refractory bricks, and the refractory bricks are built in at least three layers from the inside to the outside, and the refractory bricks in the outermost layer have an interlocking structure.

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