Channel dusting prevention for increasing ventilation in a double chamber kiln

Abstract

The utility model relates to double hearth kiln technical field especially is concerned about a kind of prevent passage dust accumulation increase ventilation double hearth kiln, including outer ring wall, arch bridge, annular passage and several corbels, the outer ring wall is kiln body inside annular wall body structure, the arch bridge is straddled on outer ring wall top and is fixedly connected with outer ring wall, the corbel is set to outer ring wall inboard and top and arch bridge bottom abuts to realize support, the annular passage is formed in the annular space surrounded by corbel, outer ring wall and arch bridge, the corbel is evenly distributed along the circumference of outer ring wall, the corbel has the corbel top of oblique arrangement, the corbel uses custom-made refractory brick masonry, effectively solve the passage dust accumulation in prior art easy to cause blockage and the problem that cleaning maintenance is difficult after blockage.

Description

Technical Field

[0001] This utility model relates to the field of double-chamber kiln technology, and in particular to a double-chamber kiln that prevents ash accumulation in the passageway and increases ventilation. Background Technology

[0002] The double-chamber kiln, also known as a double-chamber parallel-flow regenerative lime kiln, has a core advantage in its unique thermal characteristics: fuel enters the kiln from the calcination zone through a spray gun and flows parallel to the raw material, allowing the raw material to fully absorb the heat released by the fuel, and the average temperature of the calcination zone remains stable at 950℃; at the same time, the double-chamber kiln utilizes the principle of heat storage to preheat the combustion air, and the combination of parallel-flow calcination and counter-flow heat storage makes its thermal efficiency significantly higher than other types of lime kilns such as rotary kilns and sleeve kilns, with lower heat energy consumption, and it is widely used in the lime production field.

[0003] Existing double-chamber vertical kilns in China are mainly divided into two types: suspended cylinder type and corbel type. Among them, the corbel type double-chamber kiln, due to structural stability requirements, typically uses a large number of corbels to support the internal structure of the kiln. However, this structure has significant drawbacks: 1. Dust accumulation and blockage in the channel: Excessive brackets result in a narrow cross-section of the annular channel, and the connection between the brackets and the channel wall easily forms a dead corner for dust accumulation. During the production process, dust tends to accumulate on the upper part of the brackets, which can easily cause blockage of the annular channel in the long run, seriously affecting ventilation efficiency, and thus leading to uneven calcination temperature and reduced calcination quality of raw materials.

[0004] 2. Difficult to clean and maintain: After the passage is blocked, operators need to clean it frequently, which not only increases the labor intensity of personnel, but also requires the kiln to be shut down and production to be stopped during the cleaning process, which directly leads to a decrease in output, resulting in idle equipment losses and increased production costs. Utility Model Content

[0005] This invention addresses the shortcomings of existing technologies by providing a method to prevent dust accumulation in the ventilation channels of a double-chamber kiln, effectively solving the problems of dust accumulation in the channels leading to blockages and the difficulty of cleaning and maintenance after blockage.

[0006] The technical solution adopted by this utility model to solve the above problems is as follows: A double-chamber kiln designed to prevent ash accumulation in the passageway and increase ventilation includes an outer ring wall, an arch bridge, an annular passageway, and several corbels. The outer ring wall is an internal annular wall structure of the kiln body. The arch bridge spans the top of the outer ring wall and is fixedly connected to it. The corbels are located on the inner side of the outer ring wall, with their tops abutting against the bottom of the arch bridge for support. The annular passageway is formed within the annular space enclosed by the corbels, the outer ring wall, and the arch bridge. The corbels are evenly distributed along the circumference of the outer ring wall, and each corbel has an inclined top. The corbels are constructed using custom-made refractory bricks.

[0007] Preferably, the top of the cow leg is set at an angle to the horizontal direction.

[0008] Preferably, the customized refractory brick includes an arc-shaped support part that fits into the bottom of the arch bridge and a right-angle connecting part that is fixed to the inner side of the outer ring wall. The curvature of the arc-shaped support part matches the curvature of the bottom of the arch bridge, and the right-angle connecting part is fixed to the refractory brick layer on the inner side of the outer ring wall by a masonry method.

[0009] Preferably, the mortar joint of the custom refractory bricks is 3mm.

[0010] Preferably, the connection points between the corbel and the outer ring wall and the arch bridge are seamlessly transitioned using custom-made refractory bricks.

[0011] Compared with the prior art, this utility model has the following advantages: The top of the corbel forms a 60° angle with the horizontal direction. When dust particles carried by the airflow come into contact with the top of the corbel, they slide down the slope to the bottom of the annular channel under the action of gravity because there are no dead corners on the inclined surface. This avoids the formation of a dust accumulation layer on the top of the corbel. The connection between the corbel and the outer ring wall and the arch bridge is seamlessly transitioned by custom-made refractory bricks. There are no protrusions, depressions or wide gaps in traditional structures, which prevents dust from accumulating in the dead corners of the connection. At the same time, the 3mm masonry gap creates capillary resistance, reducing the amount of dust actively embedded in the gap. Even if a small amount of dust adheres, it can be quickly removed by airflow, ensuring that the effective cross-sectional area of ​​the annular channel remains stable at all times. Attached Figure Description

[0012] Figure 1 This is a top view of the annular channel of a double-chamber kiln that increases ventilation by preventing ash accumulation in the channel according to the present invention; Figure 2 This is a cross-sectional view of the outer ring wall of a double-chamber kiln that increases ventilation by preventing dust accumulation in the passageway, according to the present invention. Figure 3 This is a schematic diagram of the external flame-spraying pipe of a double-chamber kiln that increases ventilation by preventing ash accumulation in the passageway according to this utility model. The numbers in the diagram are: 1-bracket, 2-bracket top, 3-circular channel, 4-outer ring wall, 5-arch bridge, 6-fuel spray gun, 7-external flamethrower pipe, 8-arc support, 9-right angle connection. Detailed Implementation

[0013] The following are specific embodiments of the present invention, and the technical solution of the present invention will be further described in conjunction with the accompanying drawings. However, the present invention is not limited to these embodiments.

[0014] like Figure 1-3As shown, a double-chamber kiln designed to prevent ash accumulation in the passageway and increase ventilation includes an outer ring wall 4, an arch bridge 5, an annular passage 3, and several corbels 1. The outer ring wall 4 is an internal annular wall structure of the kiln body. The arch bridge 5 spans the top of the outer ring wall 4 and is fixedly connected to the outer ring wall 4. The corbels 1 are located on the inner side of the outer ring wall 4, with their tops abutting against the bottom of the arch bridge 5 for support. The annular passage 3 is formed within the annular space enclosed by the corbels 1, the outer ring wall 4, and the arch bridge 5. The corbels 1 are evenly distributed around the circumference of the outer ring wall 4. Each corbel 1 has an inclined corbel top 2 and is constructed using custom-made refractory bricks.

[0015] The top 2 of the cow leg is set at an angle to the horizontal direction.

[0016] like Figure 1 and 2 As shown, the angle between the top 2 of the cow leg and the horizontal direction is set to 60°, which is larger than the traditional angle of 45° between the top 2 of the cow leg and the horizontal direction. By increasing the tilt angle, the dust can slide down the top 2 of the cow leg into the annular channel 3 under the action of gravity, thus avoiding the formation of a dust accumulation layer on the top 2 of the cow leg.

[0017] The customized refractory bricks include an arc-shaped support part 8 that fits into the bottom of the arch bridge 5 and a right-angle connecting part 9 that is fixed to the inner side of the outer ring wall 4. The curvature of the arc-shaped support part 8 matches the curvature of the bottom of the arch bridge 5, and the right-angle connecting part 9 is fixed to the refractory brick layer on the inner side of the outer ring wall 4 by masonry.

[0018] The connection points between the corbel 1 and the outer ring wall 4 and the arch bridge 5 are all seamlessly transitioned using custom-made refractory bricks.

[0019] like Figure 2 and 3As shown, the curvature of the arc-shaped support 8 matches the curvature of the bottom of the arch bridge 5, which allows the custom-made refractory bricks to fit tightly against the bottom of the arch bridge 5. During the operation of the double-chamber kiln, the kiln is in a high-temperature environment, and the arch bridge 5 needs to withstand the weight of the materials above and its own structure. The tightly fitted arc-shaped support 8 can evenly distribute the pressure transmitted from the arch bridge 5, avoiding the loosening and damage of the refractory bricks due to uneven local stress, thereby ensuring the reliability of the corbel 1 in supporting the arch bridge 5 and maintaining the stability of the entire kiln structure; the right-angle connection 9 and the outer ring wall 4 The inner refractory brick layer is fixed by masonry, which strengthens the connection between the corbel 1 and the outer ring wall 4. Under the influence of thermal expansion and contraction at high temperatures in the kiln and the forces generated by material movement, the firm connection can prevent gaps or separation between the corbel 1 and the outer ring wall 4, ensuring that the corbel 1 stably supports the arch bridge and that the kiln structure can maintain its overall integrity under complex working conditions. The arc-shaped support part 8 and the right-angle connection part 9 of the custom refractory bricks can achieve a seamless transition between the corbel 1 and the arch bridge 5 and the outer ring wall 4, avoiding gaps, protrusions or depressions that may occur in traditional connection methods. These parts are often dead corners for ash accumulation in traditional double-chamber kilns, which can easily lead to dust accumulation. The design of the custom refractory bricks reduces the possibility of ash accumulation, helps to maintain smooth ventilation in the annular channel 3, and reduces the adverse effects on the calcination process caused by ash clogging the annular channel 3. The corbel 1 is evenly distributed around the outer ring wall 4, which optimizes the structure of the annular channel 3, making the gas flow more smoothly in the channel, reducing ventilation resistance, and significantly improving ventilation efficiency.

[0020] The mortar joints of the custom-made refractory bricks are 3mm.

[0021] like Figure 1 As shown, the refractory brickwork gaps in traditional corbel-type double-chamber kilns are typically 5-8mm. Wider gaps easily become dead zones for dust accumulation. During production, dust inside the kiln embeds itself into these gaps with the airflow. Long-term accumulation not only makes cleaning difficult but also gradually extends outwards, reducing the effective cross-sectional area of ​​the annular channel 3 and even causing localized blockages. A narrow 3mm gap significantly reduces the likelihood of dust embedding. Firstly, the gap width is smaller than the diameter of most dust particles. The particle size of calcined dust inside the kiln is mostly 5-20μm. Although a 3mm gap is much larger than the particles, the capillary resistance created by the narrow gap reduces the amount of dust actively embedding. Secondly, even if a small amount of dust adheres, the narrow gap prevents the formation of deep ash accumulation, which can be removed by subsequent airflow sweeping or light cleaning. Combined with the self-sliding design of the inclined corbel top 2, the core hidden danger of ash accumulation and blockage can be eliminated from a structural perspective.

[0022] The working process of this utility model is as follows: After being screened, the limestone raw material is evenly fed into the kiln through the feeding device at the top of the kiln body. The raw material initially accumulates in the kiln cavity area above the arch bridge 5. Relying on its own gravity, the raw material slowly moves downward along the inner wall of the kiln cavity. During the process, it initially contacts the high temperature environment inside the kiln and completes the preheating and temperature rise. The arch bridge 5 bears the weight load of the raw material above. Its bottom is closely fitted with the bracket 1 through the arc-shaped support part 8 of the customized refractory brick. The curvature of the arc-shaped support part 8 is completely matched with the curvature of the bottom of the arch bridge 5, which can evenly transfer the gravity to the bracket 1. Then, the bracket 1 transfers the gravity to the outer ring wall 4 through the right-angle connection part 9, avoiding deformation of the arch bridge 5 due to uneven local stress and ensuring the structural stability during the raw material transportation process.

[0023] When the raw materials move down to the calcination zone, fuels such as coal gas and natural gas are transported through external pipelines into the externally distributed flame-spraying pipes 7 around the kiln body, and then evenly sprayed into the calcination zone area through each fuel spray gun 6.

[0024] Because the fuel spray guns 6 are evenly arranged around the circumference of the kiln, and with the smooth airflow of the annular channel 3, the high-temperature airflow generated by combustion can form a uniform annular flame field in the kiln, avoiding the problem of local overheating or local oxygen deficiency caused by uneven fuel distribution in traditional double-chamber kilns, ensuring improved combustion efficiency, and reducing dust and impurities generated by incomplete combustion.

[0025] The carbon dioxide gas and unburned dust generated during calcination flow towards the annular channel 3 with the airflow inside the kiln. The top 2 of the corbel forms a 60° angle with the horizontal direction. When the dust particles carried by the airflow come into contact with the top 2 of the corbel, they slide down the inclined surface to the bottom of the annular channel 3 under the action of gravity because there are no dead corners. This avoids the formation of a dust accumulation layer on the top 2 of the corbel. The connection between the corbel 1 and the outer ring wall 4 and the arch bridge 5 is seamlessly transitioned by custom-made refractory bricks. There are no protrusions, depressions or wide gaps in the traditional structure, which prevents dust from accumulating in the dead corners of the connection. At the same time, the 3mm masonry gap creates capillary resistance, reducing the amount of dust actively embedded in the gap. Even if a small amount of dust is attached, it can be quickly removed by airflow, ensuring that the effective cross-sectional area of ​​the annular channel 3 remains stable.

[0026] The specific embodiments described herein are merely illustrative examples illustrating the spirit of this utility model. Those skilled in the art to which this utility model pertains may make various modifications or additions to the described specific embodiments or use similar methods to replace them, without departing from the spirit of this utility model or exceeding the scope defined by the appended claims.

Claims

1. A double-chamber kiln for preventing ash accumulation in the passageway and increasing ventilation, comprising an outer ring wall (4), an arch bridge (5), an annular passage (3), and several corbels (1), wherein the outer ring wall (4) is an internal annular wall structure of the kiln body, the arch bridge (5) spans the top of the outer ring wall (4) and is fixedly connected to the outer ring wall (4), the corbels (1) are arranged on the inner side of the outer ring wall (4) and their tops abut against the bottom of the arch bridge (5) for support, and the annular passage (3) is formed within the annular space enclosed by the corbels (1), the outer ring wall (4), and the arch bridge (5), characterized in that: The corbels (1) are evenly distributed around the outer ring wall (4), and the corbels (1) have a corbel top (2) set at an incline. The corbels (1) are constructed using custom-made fire-resistant bricks.

2. The double-chamber kiln for preventing ash accumulation in the passageway and increasing ventilation as described in claim 1, characterized in that: The top of the cow leg (2) is set at an angle to the horizontal direction.

3. The double-chamber kiln for preventing ash accumulation in the passageway and increasing ventilation as described in claim 1, characterized in that: The customized refractory bricks include an arc-shaped support (8) that fits into the bottom of the arch bridge (5) and a right-angle connecting part (9) that is fixed to the inner side of the outer ring wall (4). The curvature of the arc-shaped support (8) matches the curvature of the bottom of the arch bridge (5), and the right-angle connecting part (9) is fixed to the refractory brick layer on the inner side of the outer ring wall (4) by masonry.

4. The double-chamber kiln for preventing ash accumulation in the passageway and increasing ventilation as described in claim 1, characterized in that: The mortar joints of the custom-made refractory bricks are 3mm.

5. The double-chamber kiln for preventing ash accumulation in the passageway and increasing ventilation as described in claim 1, characterized in that: The connection between the corbel (1) and the outer ring wall (4) and the arch bridge (5) is seamlessly transitioned by custom-made refractory bricks.

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