Lining structure of rotary kiln for calcining acidic materials

Abstract

The utility model relates to the technical field of rotary kilns, in particular to a lining structure of a rotary kiln for calcining acidic materials. The barrel is sequentially divided into a feeding section, a reducing section, a main body section and a discharging section from the feeding end to the discharging end; a lining is arranged on the inner wall of the cylinder body and consists of different functional layers, and the functional layers are sequentially an anti-erosion acid-resistant composite brick layer, a high-wear-resistant acid-resistant anti-stripping composite brick layer, an andalusite composite brick layer and a mullite castable layer from the feeding end to the discharging end. According to the utility model, the linings with different characteristics are arranged in the rotary kiln in sections, so that the damage of calcined acidic materials to the linings is reduced, the service life of the rotary kiln is prolonged, and the maintenance period is prolonged; the stability of the lining is improved through the arrangement of the brick blocking ring, the retention time of materials in the rotary kiln is prolonged through the arrangement of the material blocking ring, and the calcination effect is improved; all the structures are matched with one another, the overall performance of the rotary kiln is improved, and production is facilitated.

Description

Technical Field

[0001] The utility model belongs to the technical field of rotary kilns, and in particular relates to a lining structure of a rotary kiln for calcining acidic materials. Background Art

[0002] Currently, acidic materials are calcined using three main methods: indirect calcination, direct calcination, or a combination of indirect and direct calcination. The material undergoes a rotating, forward motion within the kiln. Because acidic materials are extremely corrosive to the kiln material during calcination, and require high wear resistance from the kiln walls, conventional rotary kilns cannot meet these requirements. This results in frequent maintenance and poor calcination results, hindering production. Therefore, a lining structure for rotary kilns used to calcine acidic materials is needed to address these technical issues. Utility Model Content

[0003] To address the above-mentioned defects in the prior art, the present invention provides a rotary kiln lining structure for calcining acidic materials, comprising a rotary kiln cylinder; the cylinder is divided into a feed section, a diameter-changing section, a main section, and a discharge section in sequence from the feed end to the discharge end;

[0004] The inner wall of the cylinder is provided with an inner lining, which is composed of composite refractory bricks with different functions. The composite refractory bricks are erosion-resistant and acid-resistant composite bricks, high-wear-resistant and acid-resistant and spalling-resistant composite bricks, andalusite composite bricks and mullite castables in order from the feed end to the discharge end; the linings of the feed section, the reducing section and the end of the main section close to the reducing section are all erosion-resistant and acid-resistant composite bricks, the lining of the middle part of the main section is high-wear-resistant and acid-resistant and spalling-resistant composite bricks, and the linings of the remaining main sections are andalusite composite bricks. The inner lining of each section is a mullite castable layer; the erosion-resistant and acid-resistant composite bricks are acid-resistant and erosion-resistant; the highly wear-resistant and acid-resistant spalling-resistant composite bricks are acid-resistant, wear-resistant and slag-resistant; the andalusite composite bricks are high-temperature-resistant, wear-resistant and corrosion-resistant; the mullite castables are wear-resistant and have good thermal shock resistance. Different linings are set in different working sections of the rotary kiln to reduce the damage of the calcined acidic materials to the lining, thereby increasing the service life of the rotary kiln, extending the maintenance cycle, and improving the calcination effect.

[0005] The main section is provided with a plurality of retaining brick rings, the outer ring surface of which contacts the inner wall of the cylinder. Since the rotary kiln has a certain slope when installed, several retaining brick rings are provided on the entire cylinder to make the lining more stable and strong; the main section is provided with a circle of raised retaining rings at one end close to the discharge section, which can increase the time the material stays in the cylinder and improve the calcination effect.

[0006] Preferably, the linings of the feed section, the variable diameter section and the main section near the end of the variable diameter section are all made of corrosion-resistant and acid-resistant composite bricks, the lining of the middle part of the main section is made of highly wear-resistant, acid-resistant and spalling-resistant composite bricks, the linings of the remaining main sections are made of andalusite composite bricks, and the lining of the discharge section is made of mullite castable material;

[0007] Preferably, the composite refractory bricks between two adjacent retaining brick rings, excluding the retaining ring, contain an insulating layer. The insulating layer prevents heat dissipation, and the strength of composite refractory bricks without an insulating layer is higher than that of composite refractory bricks with an insulating layer. Therefore, the composite refractory bricks used in the retaining ring, retaining brick ring, and reducing section do not contain an insulating layer, which can reduce heat dissipation in the rotary kiln while maintaining the required strength of the lining.

[0008] Preferably, the cross section of the retaining ring is conical, which allows the retaining ring to have a certain retaining effect without affecting the discharge of the material.

[0009] Preferably, the contact surface of the composite refractory brick with the inner wall of the cylinder is arc surface 1, and the surface away from the inner wall is arc surface 2. The arc length of arc surface 1 of the composite refractory brick is greater than the arc length of arc surface 2, and the line connecting the center of arc surface 1 and the center of arc surface 2 lies on a radius of the cylinder. The inner lining is composed of spliced composite refractory bricks. This arrangement ensures the stability of the inner lining and prevents the composite refractory bricks located above the rotary kiln from falling.

[0010] The present invention also includes other components that enable the normal use of the lining structure of a rotary kiln for calcining acidic materials, all of which are conventional technical means in the field. In addition, devices or components not limited in the present invention all adopt conventional technical means and conventional equipment in the field.

[0011] The beneficial effects of the utility model are as follows: composite refractory brick linings with different characteristics are arranged in sections in the rotary kiln, which reduces the damage of the calcined acidic materials to the lining, increases the service life of the rotary kiln, and prolongs the maintenance cycle; the arrangement of the brick retaining ring improves the stability of the lining, and the arrangement of the material retaining ring increases the residence time of the material in the rotary kiln, thereby improving the calcination effect; the various structures cooperate with each other, improve the overall performance of the rotary kiln, and are beneficial to production. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0013] Figure 1 This is a schematic structural diagram of a rotary kiln lining structure for calcining acidic materials in an embodiment of the present utility model;

[0014] Figure 2 for Figure 1 A magnified view of the inner lining with thermal insulation at point A;

[0015] Figure 3 for Figure 1 A magnified view of the inner lining without insulation at B in the middle;

[0016] Figure 4 for Figure 1 View from CC in the middle.

[0017] In the figure: 1. Cylinder; 2. Feed section; 3. Lining; 4. Feed end; 5. Discharge end; 6. Baffle ring; 7. Corrosion-resistant and acid-resistant composite bricks; 8. Highly wear-resistant, acid-resistant and spalling-resistant composite bricks; 9. Andalusite composite bricks; 10. Mullite castable; 11. Brick baffle ring; 12. Variable diameter section; 13. Insulation layer. DETAILED DESCRIPTION

[0018] The present invention is described below in conjunction with the accompanying drawings and specific embodiments of the present invention. The description herein is intended only to explain the present invention and is not intended to limit the present invention. Based on the embodiments of the present invention, any modifications, equivalent substitutions, improvements, etc. made by those skilled in the art without creative work to all other embodiments obtained based on the embodiments of the present invention shall be included within the scope of protection of the present invention.

[0019] Example

[0020] like Figure 1-4 As shown, the utility model provides a rotary kiln lining structure for calcining acidic materials, comprising a rotary kiln cylinder 1; the cylinder 1 is divided into a feed section 2, a diameter-reducing section 12, a main section and a discharge section along the feed end 4 to the discharge end 5;

[0021] The inner wall of the cylinder 1 is provided with an inner lining 3, which is composed of composite refractory bricks with different functions. The composite refractory bricks are erosion-resistant and acid-resistant composite bricks, high-wear-resistant and acid-resistant and spalling-resistant composite bricks, andalusite composite bricks and mullite castables in order from the feed end to the discharge end; the inner lining 3 of the feed section 2, the variable diameter section 12 and the end of the main section close to the variable diameter section 12 are all erosion-resistant and acid-resistant composite bricks 7, the inner lining 3 of the middle part of the main section is high-wear-resistant and acid-resistant and spalling-resistant composite bricks 8, and the inner lining 3 of the remaining main sections is andalusite composite bricks 9, and the discharge end is provided with an inner lining 3 of the feed section 2, the variable diameter section 12 and the end of the main section close to the variable diameter section 12. The inner lining 3 of the material section is a mullite castable 10; the erosion-resistant and acid-resistant composite brick 7 has the characteristics of acid resistance and erosion resistance, the highly wear-resistant and acid-resistant spalling-resistant composite brick 8 has the characteristics of acid resistance, wear resistance and slag resistance, the andalusite composite brick 9 has the characteristics of high temperature resistance, wear resistance and corrosion resistance, and the mullite castable layer 10 has the characteristics of wear resistance and good thermal shock resistance. Different inner liners 3 are set in different working sections of the rotary kiln to reduce the damage of the calcined acidic materials to the inner lining 3, thereby increasing the service life of the rotary kiln, extending the maintenance cycle, and improving the calcination effect.

[0022] The main section is provided with a plurality of retaining brick rings 11, the outer ring surface of the retaining brick ring 11 contacts the inner wall of the cylinder 1. Since the rotary kiln has a certain slope when installed, a plurality of retaining brick rings 11 are provided on the entire cylinder 1 to make the lining 3 more stable and strong; a circle of raised retaining rings 6 is provided at one end of the main section close to the discharge section, which can increase the time the material stays in the cylinder 1 and improve the calcination effect.

[0023] The composite refractory bricks between two adjacent retaining brick rings 11, except for the retaining ring 6, contain an insulating layer 13. The provision of the insulating layer 13 prevents heat from dissipating, and the strength of composite refractory bricks without an insulating layer is higher than that of composite refractory bricks with an insulating layer. Therefore, the composite refractory bricks of the retaining ring 6, the retaining brick ring 11, and the reducing section 12 do not contain an insulating layer, which reduces heat dissipation in the rotary kiln while maintaining the required strength of the lining 3.

[0024] The cross section of the retaining ring 6 is tapered, which allows the retaining ring 6 to have a certain retaining effect without affecting the discharge of the material.

[0025] The contact surface between the composite refractory brick and the inner wall of the cylinder 1 is arc surface 1, and the surface of the composite refractory brick away from the inner wall of the cylinder 1 is arc surface 2. The arc length of arc surface 1 is greater than the arc length of arc surface 2, and the line connecting the center of arc surface 1 and the center of arc surface 2 is located on a radius of the cylinder 1. The lining 3 is spliced with composite refractory bricks. This arrangement ensures the stability of the lining 3 and prevents the composite refractory bricks located above the rotary kiln from falling.

[0026] Working principle: Anti-erosion and acid-resistant composite bricks are acid-resistant and erosion-resistant; highly wear-resistant and acid-resistant anti-stripping composite bricks are acid-resistant, wear-resistant and slag-resistant; andalusite composite bricks are high-temperature-resistant, wear-resistant and corrosion-resistant; mullite castable layer is wear-resistant and has good thermal shock resistance. Different linings are set in different working sections of the rotary kiln to reduce the damage of the calcined acidic materials to the lining, thereby increasing the service life of the rotary kiln, extending the maintenance cycle, and improving the calcination effect.

[0027] This embodiment reduces the damage of the calcined acidic materials to the lining by arranging composite refractory bricks with different characteristics in sections in the rotary kiln, thereby increasing the service life of the rotary kiln and extending the maintenance cycle; the arrangement of the brick retaining ring improves the stability of the lining, and the arrangement of the material retaining ring increases the residence time of the material in the rotary kiln, thereby improving the calcination effect; the various structures cooperate with each other to improve the overall performance of the rotary kiln and facilitate production.

[0028] The composite refractory bricks with an insulating layer, the composite refractory bricks without an insulating layer, the erosion-resistant and acid-resistant composite bricks, the highly wear-resistant, acid-resistant and spalling-resistant composite bricks, the andalusite composite bricks and the mullite castables in this embodiment are all prior art. This application does not make any improvements to them, but only utilizes their existing functions. For their specific structures and principles, please refer to the product manual or existing technical materials, which are all prior art.

[0029] While the embodiments of the present invention have been described above, the foregoing description is intended to be illustrative, non-exhaustive, and not limited to the disclosed embodiments. Numerous modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention are intended to be included within the scope of protection of the present invention.

Claims

1. A rotary kiln lining structure for calcining acidic materials, comprising a rotary kiln cylinder; characterized in that: The cylinder is divided into a feeding section, a diameter-changing section, a main section and a discharging section in sequence from the feeding end to the discharging end; The inner wall of the cylinder is provided with an inner lining, which is composed of composite refractory bricks with different functions. The composite refractory bricks are erosion-resistant and acid-resistant composite bricks, high-wear-resistant and acid-resistant and spalling-resistant composite bricks, andalusite composite bricks and mullite castables in order from the feed end to the discharge end. The main body section is provided with a plurality of brick retaining rings, the outer ring surfaces of the brick retaining rings are in contact with the inner wall of the cylinder, and one end of the main body section close to the discharge section is provided with a circle of raised retaining rings.

2. The lining structure of a rotary kiln for calcining acidic materials according to claim 1, characterized in that: A heat insulation layer is provided in the composite refractory bricks between two adjacent retaining brick rings except the retaining ring.

3. The lining structure of a rotary kiln for calcining acidic materials according to claim 1, characterized in that: The cross section of the retaining ring is conical.

4. The lining structure of a rotary kiln for calcining acidic materials according to claim 1, characterized in that: The contact surface between the composite refractory brick and the inner wall of the cylinder is arc surface 1, and the surface away from the inner wall of the cylinder is arc surface 2. The arc length of arc surface 1 of each composite refractory brick is greater than the arc length of arc surface 2, and the line connecting the center of arc surface 1 and the center of arc surface 2 is located on a radius of the cylinder.

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