Energy-saving and heat-insulating structure of rotary kiln

Abstract

The utility model relates to the technical field of rotary kilns, in particular to an energy-saving heat preservation structure of a rotary kiln. Comprising a rotary kiln cylinder and a refractory lining arranged in the rotary kiln cylinder, a composite heat preservation layer is arranged between the inner wall of the rotary kiln cylinder and the refractory lining, the composite heat preservation layer comprises a heat insulation plate and a heat insulation bonding coating arranged between the heat insulation plate and the inner wall of the rotary kiln cylinder, and the heat insulation bonding coating is used for heat insulation and used for bonding and fixing the heat insulation plate. And one surface of the heat insulation plate is coated with a heat insulation bonding coating. The heat insulation bonding coatings on the inner wall of the rotary kiln cylinder and the surface of the heat insulation plate are combined with the multi-structure staggered arrangement design, and the heat insulation efficiency, the structural reliability and the economical efficiency are remarkably improved through the synergistic effect of three mechanisms of heat resistance superposition, stress buffering and construction optimization.

Description

Technical Field

[0001] The utility model relates to the technical field of rotary kilns, in particular to an energy-saving and heat-insulating structure of a rotary kiln. Background Art

[0002] In industrial production, rotary kilns are an important type of thermal equipment and are widely used in cement, metallurgy, chemical industry and other fields. However, during the operation of the rotary kiln, a large amount of heat is lost due to the heat conduction between the high-temperature flue gas and the cylinder, which not only reduces the thermal efficiency and increases energy consumption, but also makes the temperature of the outer wall of the cylinder too high, posing a safety hazard and possibly causing thermal pollution to the surrounding environment. Traditional rotary kiln insulation structures mostly use a single refractory material layer for insulation, but this structure often fails to achieve the ideal insulation effect. On the one hand, the thermal resistance of a single refractory material layer is limited, and it is difficult to effectively block the heat conduction of high-temperature flue gas; on the other hand, the refractory material layer is prone to aging, cracking and other problems under long-term high-temperature conditions, further reducing the insulation performance and service life.

[0003] In the prior art, the patent document with the authorization announcement number CN220829070U discloses an energy-saving masonry structure of a rotary kiln, including a rotary kiln cylinder, the inner wall of which is provided with a refractory lining formed by refractory brick masonry, and an insulating layer is built between the inner wall surface of the rotary kiln cylinder and the outer wall surface of the refractory lining, the insulating layer is composed of a plurality of insulating plates, the plurality of insulating plates are attached to the inner wall surface of the rotary kiln cylinder through a fire mud bonding layer, and the refractory lining is attached to the inner surface of the insulating layer through a fire mud bonding layer. This structural design enhances the thermal insulation performance of the rotary kiln to a certain extent and reduces heat loss, but the heat flux density at the masonry joint of the structure is high, which will form a significant heat loss channel. In addition, the structural strength is low and the thermal shock stability is poor. Utility Model Content

[0004] The utility model provides a rotary kiln energy-saving and heat-insulating structure to solve the technical problems of low thermal efficiency, short service life and poor anti-seismic performance of the rotary kiln heat-insulating structure in the prior art.

[0005] In order to solve the above problems, the utility model provides a rotary kiln energy-saving and heat-insulating structure adopts the following technical solutions:

[0006] The invention comprises a rotary kiln cylinder and a refractory lining arranged inside the rotary kiln cylinder, a composite thermal insulation layer is arranged between the inner wall of the rotary kiln cylinder and the refractory lining, the composite thermal insulation layer comprises a thermal insulation board and a thermal insulation bonding coating arranged between the thermal insulation board and the inner wall of the rotary kiln cylinder, the thermal insulation bonding coating is used for thermal insulation and for bonding and fixing the thermal insulation board, and the surface of the thermal insulation board close to the inner wall of the rotary kiln cylinder is coated with the thermal insulation bonding coating;

[0007] The heat insulation panels are arranged in a staggered array.

[0008] Further, the heat insulation plates are arranged in several groups closely along the axial direction of the rotary kiln cylinder body, each group of heat insulation plates is arranged closely along the circumferential direction of the inner wall of the rotary kiln cylinder body, and the heat insulation plates of adjacent groups are arranged staggeredly.

[0009] Further, the dislocation amount between adjacent groups of heat insulation plates is 1 / 3 - 1 / 2 of the width of the heat insulation plate.

[0010] Further, the refractory lining is composed of several refractory bricks, and the boundary formed between adjacent refractory bricks does not correspond to the boundary formed between two adjacent heat insulation plates in the same group of heat insulation plates.

[0011] Further, the refractory brick is pressed on the boundary formed between adjacent groups of heat insulation plates.

[0012] Further, the thickness of the heat insulation plate is less than the thickness of the refractory brick.

[0013] Further, the thickness of the heat insulation bonding coating is 0.5mm - 5mm.

[0014] The beneficial effects of an energy-saving and heat-insulating structure of a rotary kiln provided by the utility model are as follows:

[0015] 1. The utility model realizes high-efficient heat insulation performance. The heat insulation bonding coating between the heat insulation plate and the inner wall of the rotary kiln cylinder body, that is, the heat insulation bonding coating here is directly coated on the inner wall of the rotary kiln cylinder body to form an effective heat insulation layer, blocking the direct heat conduction of high-temperature flue gas to the cylinder body. The surface heat insulation bonding coating of the heat insulation plate forms another heat insulation barrier, weakening the residual heat transfer through the micropores or joints of the heat insulation plate.

[0016] A series of coating effects are formed between the heat insulation plate and the inner wall of the rotary kiln cylinder body, significantly reducing the outer wall temperature of the rotary kiln cylinder body.

[0017] 2. The utility model realizes enhancing the overall structural strength. Through the staggered arrangement of the heat insulation plates and the misalignment design of the boundaries between the refractory bricks and the heat insulation plates, the thermal stress is effectively dispersed, reducing the stress concentration caused by the difference in thermal expansion, and reducing the risk of cracking or deformation of the composite heat insulation layer. In addition, the surface of the heat insulation plate is flat and smooth, reducing the gap when cooperating with the refractory brick, improving the overall structural stability, and avoiding the stress concentration phenomenon caused by local protrusions or depressions.

[0018] 3. The utility model realizes optimizing the construction process and improving the construction efficiency. The staggered arrangement design allows a certain construction error (such as ±2mm), reducing the rework caused by the alignment of the boundaries and improving the construction efficiency. Description of the Drawings

[0019] By reading the following detailed description with reference to the accompanying drawings, the above and other objects, features, and advantages of the exemplary embodiments of the present utility model will become readily understandable. In the drawings, several embodiments of the present utility model are shown in an exemplary rather than restrictive manner, and the same or corresponding reference numerals represent the same or corresponding parts, wherein:

[0020] Figure 1 is a schematic structural view of the energy-saving and heat-insulating structure of the rotary kiln of the present utility model;

[0021] Figure 2 is a cross-sectional view of the energy-saving and heat-insulating structure of the rotary kiln of the present utility model;

[0022] Figure 3 is Figure 2 a partial enlarged view of area A in

[0023] Explanation of reference numerals:

[0024] 1, rotary kiln cylinder; 2, refractory lining; 21, refractory brick; 3, composite heat-insulating layer; 31, heat-insulating board; 32, heat-insulating bonding coating. Specific embodiments

[0025] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present utility model. Those skilled in the art should know that the embodiments described below are a part of the embodiments of the present disclosure, rather than all of the embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without making creative efforts belong to the scope of protection of the present utility model.

[0026] The number of any element in the drawings is for illustration rather than limitation, and any naming is only for distinction and does not have any limiting meaning.

[0027] Next, with reference to several representative embodiments of the present utility model, the principles and spirits of the present utility model will be elaborated in detail.

[0028] An embodiment of an energy-saving and heat-insulating structure of a rotary kiln provided by the present utility model:

[0029] As Figures 1 to 3 shown, wherein Figure 1 in order to show the arrangement structure of the heat-insulating board 31, only one circle of the port of the refractory lining 2 is shown.

[0030] It includes a rotary kiln cylinder 1 and a refractory lining 2 disposed inside the rotary kiln cylinder 1. A composite insulation layer 3 is provided between the inner wall of the rotary kiln cylinder 1 and the refractory lining 2. The composite insulation layer 3 includes a heat insulation board 31 and a heat insulation bonding coating 32 disposed between the heat insulation board 31 and the inner wall of the rotary kiln cylinder 1. The heat insulation bonding coating 32 is used for heat insulation and for bonding and fixing the heat insulation board 31. The surface of the heat insulation board 31 close to the inner wall of the rotary kiln cylinder 1 is coated with the heat insulation bonding coating 32.

[0031] It should be noted that the material of the heat insulation bonding coating 32 in this embodiment is but not limited to a high-temperature resistant binder disclosed in the invention patent with the application number CN201710183845.2.

[0032] Among them, the thickness of the heat insulation bonding coating 32 is 1 mm.

[0033] Specifically, the composite insulation layer 3 is located between the inner wall of the rotary kiln cylinder 1 and the refractory lining 2. Its main function is to reduce the heat transfer from the refractory lining 2 to the rotary kiln cylinder 1, improve the thermal efficiency of the rotary kiln, and reduce energy consumption.

[0034] The heat insulation bonding coating 32 between the heat insulation board 31 and the inner wall of the rotary kiln cylinder 1, that is, the heat insulation bonding coating 32 here is directly coated on the inner wall of the rotary kiln cylinder 1 to form an effective heat insulation layer to block the direct heat conduction of high-temperature flue gas to the cylinder.

[0035] The heat insulation bonding coating 32 on the surface of the heat insulation board 31 forms another heat insulation barrier to weaken the residual heat transfer through the micropores or joints of the heat insulation board 31.

[0036] A series connection coating effect is formed between the heat insulation board 31 and the inner wall of the rotary kiln cylinder 1, which increases the total thermal resistance by 30%-50% and significantly reduces the outer wall temperature of the rotary kiln cylinder 1.

[0037] The heat insulation bonding coating 32 on the inner wall of the rotary kiln cylinder 1 and the surface of the heat insulation board 31 significantly improves the heat insulation efficiency, structural reliability and economy through the synergistic effect of three major mechanisms: thermal resistance superposition, stress buffering and construction optimization.

[0038] It should be noted that during the coating process of the heat insulation bonding coating 32, due to its leveling property, it automatically fills the tiny unevenness on the surface of the heat insulation board 31. After curing, a uniform and dense coating is formed, making the surface of the heat insulation board 31 reach a smooth and flat effect.

[0039] The smooth surface of the heat insulation board 31 can reduce the gaps caused by surface unevenness, improve the fitting accuracy, and enhance the overall structural stability.

[0040] In addition, a flat surface can avoid stress concentration caused by local protrusions or depressions, reducing the risk of damage to the heat insulation board 31 during use due to thermal stress or mechanical stress. This extends the service life of the heat insulation board 31 and the entire composite thermal insulation layer 3, and reduces the maintenance cost.

[0041] In this embodiment, the heat insulation boards 31 are arranged in several groups closely along the axial direction of the rotary kiln shell 1. Each group of heat insulation boards 31 is arranged closely along the circumferential direction of the inner wall of the rotary kiln shell 1, and the heat insulation boards 31 of adjacent groups are arranged staggeredly.

[0042] Among them, the staggering amount between adjacent groups of heat insulation boards 31 is 1 / 2 of the width of the heat insulation board 31.

[0043] The arrangement method between adjacent groups of heat insulation boards 31 is a staggering amount design. The staggered arrangement makes the heat insulation boards 31 more evenly distributed in the circumferential and axial directions. Overall, it helps to disperse thermal stress, reduce stress concentration caused by thermal expansion differences, and reduce the risk of cracking or deformation of the composite thermal insulation layer 3.

[0044] In this embodiment, the refractory lining 2 is composed of several refractory bricks 21. The boundary formed between adjacent refractory bricks 21 does not correspond to the boundary formed between two adjacent heat insulation boards 31 in the same group of heat insulation boards 31.

[0045] Among them, the refractory brick 21 is pressed on the boundary formed between adjacent groups of heat insulation boards 31.

[0046] Among them, the thickness of the heat insulation board 31 is less than the thickness of the refractory brick 21.

[0047] Specifically, the boundaries of the refractory bricks 21 and the heat insulation boards 31 are staggered to avoid direct heat transfer along a linear path. The staggered arrangement can reduce heat loss caused by the heat bridge effect by 40% - 60%, significantly improving the heat insulation efficiency. In addition, the staggered arrangement enables the thermal stress to be dispersed and transferred between the refractory bricks 21 and the heat insulation boards 31, reducing local stress concentration and the risk of cracking.

[0048] Furthermore, the staggered arrangement allows for construction errors (such as ±2 mm), reducing rework caused by boundary alignment.

[0049] When the energy-saving and thermal insulation structure of the rotary kiln in this embodiment is specifically applied to a Φ4.8×74 m rotary kiln, the size of the heat insulation board 31 is an axial length of 300 mm × a circumferential width of 150 mm × a thickness of 20 mm. It is arranged closely along the axial direction, and each group is closely spliced along the circumferential direction of the inner wall of the cylinder. Adjacent groups are arranged staggeredly, and the staggering amount is 75 mm. The boundaries of adjacent refractory bricks 21 are staggered from the boundaries of the heat insulation boards 31 and cover the joints of adjacent groups of heat insulation boards 31.

[0050] In the thermal performance test, compared with not setting the composite insulation layer 3, the average outer wall temperature of the rotary kiln cylinder 1 drops by 108 °C, the thermal efficiency increases by 42%, and the energy consumption reduction is 21.3%.

[0051] After 10 rapid cooling and heating cycles, there is no cracking or peeling. Stress distribution: The analysis shows that the interfacial stress between the heat insulation board 31 and the refractory brick 21 is reduced by 65%.

[0052] Based on the above description of this specification, those skilled in the art can also understand the following terms used, such as terms indicating orientation or positional relationship like "upper", "lower", "front", "rear", "left", "right", "width", "horizontal", "top", "bottom", "inner", "outer", etc. These terms are based on the orientation or positional relationship shown in the drawings of this specification. They are only for the purpose of facilitating the description of the solution of the present invention and simplifying the description, rather than explicitly or implicitly indicating that the devices or elements involved must have the specific orientation, be constructed and operated in the specific orientation. Therefore, the above terms indicating orientation or positional relationship cannot be understood or interpreted as a limitation to the solution of the present invention.

[0053] In addition, in the description of this specification, the meaning of "a plurality of" is at least two, such as two, three or more, etc., unless otherwise specifically and clearly defined.

Claims

1. A rotary kiln energy-saving and heat-insulating structure, comprising a rotary kiln cylinder body (1) and a refractory lining (2) arranged inside the rotary kiln cylinder body (1), characterized in that, A composite insulation layer (3) is provided between the inner wall of the rotary kiln cylinder body (1) and the refractory lining (2). The composite insulation layer (3) includes heat insulation boards (31) and a heat insulation bonding coating (32) provided between the heat insulation boards (31) and the inner wall of the rotary kiln cylinder body (1). The heat insulation bonding coating (32) is used for heat insulation and for bonding and fixing the heat insulation boards (31). The surface of the heat insulation board (31) close to the inner wall of the rotary kiln cylinder body (1) is coated with the heat insulation bonding coating (32). The heat insulation boards (31) are arranged in a staggered array.

2. The energy-saving and heat-insulating structure of the rotary kiln according to claim 1, wherein The heat insulation boards (31) are provided in several groups arranged closely along the axial direction of the rotary kiln cylinder body (1). Each group of heat insulation boards (31) is arranged closely along the circumferential direction of the inner wall of the rotary kiln cylinder body (1). The heat insulation boards (31) of adjacent groups are arranged in a staggered manner.

3. The energy-saving and heat-insulating structure of the rotary kiln according to claim 2, characterized in that, The dislocation amount between adjacent groups of heat insulation boards (31) is 1 / 3 - 1 / 2 of the width of the heat insulation board (31).

4. The energy-saving and heat-insulating structure of the rotary kiln according to claim 2, characterized in that, The refractory lining (2) is composed of several refractory bricks (21). The boundary formed between adjacent refractory bricks (21) does not correspond to the boundary formed between two adjacent heat insulation boards (31) in the same group of heat insulation boards (31).

5. The energy-saving and heat-insulating structure of the rotary kiln according to claim 4, characterized in that, The refractory bricks (21) are pressed on the boundary formed between adjacent groups of heat insulation boards (31).

6. The energy-saving and heat-insulating structure of the rotary kiln according to claim 4, characterized in that, The thickness of the heat insulation board (31) is less than the thickness of the refractory brick (21).

7. The energy-saving and heat-insulating structure of the rotary kiln according to claim 1, characterized in that, The thickness of the heat insulation bonding coating (32) is 0.5 mm - 5 mm.

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