Method of laying the inner ring of a c-type twin chamber kiln

Abstract

The application discloses a kind of C-type double hearth kiln inner ring masonry structure's masonry method, it is related to steel manufacturing equipment masonry field, steps include first in double hearth kiln inner ring steel structure bottom masonry ring beam structure, again pad fiber felt on the ring beam structure top, while every interval a distance is built a formwork on inner ring structure, install heat insulation plate along furnace shell direction, and in turn masonry insulating brick, along the direction of inner ring arc length, masonry profiled refractory brick is attached to the formwork two sides in the side of insulating brick, profiled refractory brick upper layer is misaligned and is masonry, the bottom surface groove of upper layer refractory brick is buckled on the top surface convex rib of lower layer refractory brick, the side convex rib of left side refractory brick is inserted into the side groove of right side refractory brick, and a layer of fiber cotton is laid between the formwork and the adjacent refractory brick layer surface layer, compared with prior art, the present masonry method realizes the sealing of brick up and down and left and right, avoids the problem that brick joint becomes larger during expansion, high-temperature airflow from kiln into insulation layer, burns and loses insulation layer.

Description

Technical Field

[0001] This invention relates to the field of steel manufacturing and equipment technology, and in particular to a method for constructing the inner ring masonry structure of a C-type double-chamber kiln. Background Technology

[0002] Double-chamber kilns offer advantages such as low energy consumption and superior product quality. A typical double-chamber kiln consists of two mirror-image semi-circular furnace chambers with a central passage. The outer C-lining is called the outer C-lining, and the lining of the central passage is called the inner C-lining. The inner end of the outer C-lining connects directly to the inner C-lining, forming a ring of bricks. Eight vertically erected cooling supports are evenly distributed at the connection between the outer and inner C-linings and around the inner C-lining, generally referred to as a "double-C structure." The double-chamber kiln lining structure, from bottom to top, is divided into a cooling zone, a calcination zone, and a preheating zone. It is constructed of insulating bricks made of high-temperature resistant, wear-resistant, and heat-insulating refractory materials, forming a "double-C structure"—multiple horizontal rings of bricks between the inner and outer C-linings. The outer ring of bricks consists of 194 layers, counted sequentially from the bottom of the kiln chamber.

[0003] The cooling zone and the bottom of the steel structure were leveled using low-cement castable before the cooling zone was constructed. From layers 1 to 40, starting from the steel shell structure outwards, the structure was constructed sequentially using a coating material, two layers of fiberboard, horizontally arranged insulating bricks, and high-strength clay bricks. The fiberboard was 30mm thick, the insulating bricks were 230mm thick, and the high-strength clay insulating bricks were 260mm thick. Expansion joints were pre-installed at regular intervals within the circular ring of the kiln's brick layer during each layer's construction. From layers 41 to 82, as the kiln height gradually approaches the calcination zone and the working temperature increases accordingly, the working layer bricks were replaced with non-standard refractory bricks. A fire-dispensing door was installed in the central passageway for observing and cleaning the kiln's operation and ash accumulation during kiln shutdowns; formwork was required during the construction of this door. The combustion zone temperature can reach up to 1100℃. Considering the calcination characteristics and temperature, the working layer bricks in the 83rd to 161st rings of the kiln's outer ring structure are constructed using mullite bricks. From the steel shell structure outwards, the layers are successively coated with mortar, two layers of fiberboard, insulating bricks, and then mullite bricks. Anchors and mortar are welded to the bottom of the steel structure inside the kiln and on the support structures to protect the steel structure. Thermocouples are also evenly distributed in the inner and outer ring areas of each kiln chamber to monitor the calcination process. Layers 162 to 194 use high-strength clay bricks as the working layer, serving as part of the preheating zone.

[0004] The entire kiln structure should be strictly symmetrical. To ensure the construction period, the construction of the two kiln chambers can be carried out simultaneously. During the construction process, overlapping of brick joints between adjacent brick layers should be avoided as much as possible, and sufficient and even mortar should be applied.

[0005] like Figure 1The double-chamber kiln calcining zone shown is constructed with a steel structure and an inner ring of refractory bricks. The bottom of the inner ring steel structure features a ring beam structure composed of anchors and castable refractory. On this ring beam structure, from the kiln exterior to the center, anchor hooks are first welded, then a coating is evenly applied, followed by two layers of thick alumina fiberboard for sealing, then two layers of lightweight clay insulating bricks, and finally, shaped refractory bricks are used for the working layer area of ​​the calcining zone. These shaped refractory bricks are made of... Figure 2 and Figure 3 The refractory bricks shown have an upward-protruding boss at the top center and an inwardly recessed platform-shaped notch at the bottom center corresponding to the boss. During construction, the boss is inserted into the platform-shaped notch, forming a vertical lock. During high-temperature firing, the refractory bricks in the inner ring of the kiln expand, causing irregularly shaped refractory bricks to expand and move to the left and right, resulting in larger brick joints. Hot air from the kiln can then penetrate into the insulation layer with lower refractoriness through the brick joints, burning the insulation bricks and coating material. Therefore, the construction structure must be modified to overcome the burning damage to the insulation bricks in the inner ring caused by the high-temperature airflow in the kiln. Summary of the Invention

[0006] The problem to be solved by the present invention is to provide a method for constructing the inner ring masonry structure of a C-type double-chamber kiln, so as to solve the problem of the expansion of brick joints due to thermal expansion of refractory materials in double-chamber kilns and the burning of the insulation bricks in the inner ring part by the high-temperature airflow in the kiln.

[0007] To solve the above problems, the technical solution of the present invention is as follows: The construction method of the inner ring masonry structure of the C-type double-chamber kiln includes the inner ring masonry structure of the C-type double-chamber kiln, which has two relatively mirrored semi-circular outer C-linings and inner C-linings in the middle channel. The two ends of the semi-circular outer C-lining are connected to the inner C-lining in a straight line to form a ring brick layer. The inner C-lining is characterized in that: the lower part of the inner C-lining is a ring beam structure composed of anchors and mullite castable. Fiber felt is laid on top of the ring beam structure, and heat insulation board is installed along the direction of the furnace shell. Then, heat-insulating bricks and shaped refractory bricks are laid in sequence. The top of the shaped refractory bricks... Both the end face and the bottom face are regularly inclined and concave towards the middle from both sides, and a top surface rib protruding upward along the length direction is provided in the middle of the top surface, and a bottom surface groove that is concave into the brick is provided at the position corresponding to the top surface rib on the bottom surface; one side of the shaped refractory brick has an outwardly protruding side rib in the middle, and the other side of the shaped refractory brick has a side groove that is concave into the brick at the position corresponding to the side rib; the front and back of the shaped refractory brick are set with an arc structure in the same direction, and the arc segment of the back is shorter than the arc segment of the front.

[0008] Its masonry methods include:

[0009] A. Weld anchors to the bottom of the inner ring steel structure of the double-chamber kiln, and pour mullite castable in sections. Use a combination of anchors and mullite castable to build the castable at the bottom of the double-chamber kiln to form a ring beam structure.

[0010] B. Lay fiber felt on top of the ring beam structure, and at the same time build a template at intervals on the inner ring structure. Weld one end of the anchor of the template to the furnace shell steel plate, and extend the other end of the anchor inward. Then pour mullite castable on the template, install the heat insulation board along the direction of the furnace shell, and build two layers of heat insulation bricks in sequence.

[0011] C. Along the inner ring arc length direction, irregular refractory bricks are laid on both sides of the template with the side of the insulation brick attached. The bottom groove of the bottom end of the irregular refractory brick in the upper layer is fastened to the top surface protrusion of the top surface of the irregular refractory brick in the lower layer. The irregular refractory brick in the upper layer and the irregular refractory brick in the lower layer are staggered and fastened. The side protrusion of the irregular refractory brick on the left side is inserted into the side groove of the irregular refractory brick on the right side, and so on.

[0012] D. Lay a layer of fiber cotton on the surface between the template and the adjacent shaped refractory brick layer. This helps to eliminate the expansion of the castable and the refractory brick. Use mullite castable to grout the shaped refractory brick and template so that the space between the brick layers is filled with castable.

[0013] E. After the brick layer has hardened, level the brick layer and lay a layer of fiber felt.

[0014] F. Repeat the masonry work according to steps BE.

[0015] A more specific embodiment of the above technical solution could be that the thickness of the fiber felt laid flat is 10 mm.

[0016] Furthermore: each layer of the template is at the same height as the brick segment layer of the shaped refractory brick, with a height of 2m-3m; a fiber felt with a thickness of 10mm is laid between the upper and lower layers of each brick segment layer; a fiber felt with a thickness of 10mm is laid between the upper and lower layers of each template.

[0017] By adopting the above technical solution, the present invention has the following advantages compared with the prior art:

[0018] Because the irregularly shaped refractory bricks used in the construction method of this invention have an arc-shaped structure on the front and back, they can fit well with the arc-shaped structure of the inner ring of the double-chamber kiln. In addition, the irregularly shaped refractory bricks have corresponding top surface ribs and bottom surface grooves on the top and bottom surfaces, and corresponding side surface ribs and side surface grooves on the sides, which achieves sealing of the bricks from top to bottom and left to right. This avoids the problem of the brick joints widening during expansion, allowing high-temperature airflow to penetrate into the insulation layer from inside the kiln and burn the insulation layer. Attached Figure Description

[0019] Figure 1 This is a layer structure diagram of the refractory material structure for the inner ring of the original C-type double-chamber kiln.

[0020] Figure 2 This is the front view of the original technology for irregularly shaped refractory bricks;

[0021] Figure 3 yes Figure 2 A bottom view;

[0022] Figure 4 This is a top view of the inner ring structure of the C-type double-chamber kiln according to an embodiment of the present invention;

[0023] Figure 5 This is a side view of the template portion of an embodiment of the present invention;

[0024] Figure 6 This is a structural diagram of the side of the C-type double-chamber kiln according to an embodiment of the present invention;

[0025] Figure 7 This is a front view of the irregularly shaped refractory brick of the present invention;

[0026] Figure 8 yes Figure 7 The left view;

[0027] Figure 9 yes Figure 7 Top view;

[0028] Figure 10 yes Figure 7 A bottom view.

[0029] Explanation of serial numbers:

[0030] 1. Ring beam structure; 2. Fiber felt; 3. Insulation board; 4. Insulating brick; 5. Shaped refractory brick; 5. Top surface rib; 5-1. Bottom surface groove; 5-2. Side surface rib; 5-3. Side surface groove; 5-4. Template; 6. Anchor; 7. Fiber cotton layer; 8. Anchor; 9. Detailed Implementation

[0031] The embodiments of the present invention will be further described in detail below with reference to the accompanying drawings:

[0032] like Figure 4 and Figure 5 The method for constructing the inner ring structure of a C-type double-chamber kiln shown includes two relatively mirrored semi-circular outer and inner C-linings with a central channel. The two ends of the semi-circular outer C-lining are connected to the inner C-lining in straight lines, forming a ring brick layer. The bottom of the inner C-lining B is a ring beam structure 1 composed of anchors 7 and mullite castable. Fiber felt 2 is laid on top of this ring beam structure, and heat insulation board 3 is installed along the direction of the furnace shell. Then, two layers of insulating bricks 4 and shaped refractory bricks 5 are laid in sequence. Figures 7-10As shown, the top and bottom surfaces of the shaped refractory brick 5 are both regularly inclined and concave towards the center from both sides. A raised top rib 5-1 is provided along the length direction in the center of the top surface, and a recessed bottom groove 5-2 is provided in the brick at a position corresponding to the top rib on the bottom surface. A raised side rib 5-3 is provided in the center of one side of the shaped refractory brick 5, and a recessed side groove is provided in the brick at a position corresponding to the side rib 5-3 on the other side of the shaped refractory brick 5. 5-4 achieves sealing of the irregularly shaped refractory brick 5 from top to bottom and left to right, preventing the brick joints from widening during expansion and allowing high-temperature airflow to penetrate the insulation layer from inside the kiln, thus burning it. The front and back of the irregularly shaped refractory brick 5 are designed with an arc structure in the same direction, and the arc segment on the back is shorter than that on the front, allowing the irregularly shaped refractory brick 5 to fit better into the arc structure of the inner ring of the double-chamber kiln. The top rib 5-1 is connected to the adjacent ends of the side rib 5-3, and the bottom groove 5-2 is connected to the adjacent ends of the side groove 5-4. Figure 1 , Figure 5 and Figure 6 As shown, at least two templates 6 are erected at intervals between the 5 layers of shaped refractory bricks along the inner arc length direction of the inner C-lining. Each template includes an anchor 7 with one end welded to the furnace shell steel plate. The other end of the anchor extends inward and mullite castable is poured onto the anchor to form a casting layer. A layer of fiber cotton 8 is laid on the surface between the template 6 and the adjacent layers of shaped refractory bricks 5. The template 6 is at the same height as the brick segment layer of shaped refractory bricks 5, with a height of 2m-3m. Fiber felt 2 is laid between the upper and lower layers of each brick segment layer, with a fiber felt thickness of 10mm. Fiber felt 2 is also laid between the upper and lower layers of each template, with a fiber felt thickness of 10mm.

[0033] The steps of this C-type double-chamber kiln inner ring masonry construction method include:

[0034] A. Weld anchors to the bottom of the inner ring steel structure of the double-chamber kiln, and pour mullite castable in sections. Use a combination of anchors and mullite castable to build the castable at the bottom of the double-chamber kiln to form a ring beam structure.

[0035] B. Lay a 10mm thick fiber felt on top of the ring beam structure, and at the same time, build a template at intervals on the inner ring structure. The template includes an anchor welded to the furnace shell steel plate at one end, and the other end of the anchor extends inward and mullite castable is poured on the anchor. Install the heat insulation board along the direction of the furnace shell, and build two layers of heat insulation bricks in sequence.

[0036] C. Along the inner ring arc length direction, irregular refractory bricks are laid on both sides of the template with the side of the insulation brick attached. The bottom groove of the bottom end of the irregular refractory brick in the upper layer is fastened to the top surface protrusion of the top surface of the irregular refractory brick in the lower layer. The irregular refractory brick in the upper layer and the irregular refractory brick in the lower layer are staggered and fastened. The side protrusion of the irregular refractory brick on the left side is inserted into the side groove of the irregular refractory brick on the right side, and so on.

[0037] D. Lay a layer of fiber cotton on the surface between the template and the adjacent shaped refractory brick layer. This helps to eliminate the expansion of the castable and the refractory brick. Use mullite castable to grout the shaped refractory brick and template so that the space between the brick layers is filled with castable.

[0038] E. After the brick layer has hardened, level the brick layer and lay a 10mm thick layer of fiber felt.

[0039] F. Repeat the masonry work according to steps BE.

Claims

1. A method for constructing a C-shaped double-chamber kiln inner ring masonry structure, comprising a C-shaped double-chamber kiln inner ring masonry structure, the structure having two relatively mirrored semicircular outer C-linings and inner C-linings with a central channel, wherein the two ends of the semicircular outer C-lining are connected to the inner C-lining by straight lines to form a ring brick layer, characterized in that: The inner C-shaped substrate is a ring beam structure composed of anchors and mullite castable. Fiber felt is laid on top of the ring beam structure, and a heat insulation board is installed along the direction of the furnace shell. Then, heat-insulating bricks and shaped refractory bricks are laid in sequence. The top and bottom surfaces of the shaped refractory bricks are regularly inclined and concave towards the middle from both sides. A top surface rib is provided along the length direction in the middle of the top surface, and a bottom surface groove is provided inward on the bottom surface at the position corresponding to the top surface rib. A side rib is provided inward in the middle of one side of the shaped refractory brick, and a side groove is provided inward on the other side of the shaped refractory brick at the position corresponding to the side rib. The front and back sides of the shaped refractory brick are set with arc structures in the same direction, and the arc segment on the back side is shorter than the arc segment on the front side. Its masonry methods include: A. Weld anchors to the bottom of the inner ring steel structure of the double-chamber kiln, and pour mullite castable in sections. Use a combination of anchors and mullite castable to build the castable at the bottom of the double-chamber kiln to form a ring beam structure. B. Lay fiber felt on top of the ring beam structure, and at the same time build a template at intervals on the inner ring structure. Weld one end of the anchor of the template to the furnace shell steel plate, and extend the other end of the anchor inward. Install the heat insulation board along the direction of the furnace shell, and build two layers of heat insulation bricks in sequence. C. Along the inner ring arc length direction, irregular refractory bricks are laid on both sides of the template with the side of the insulation brick attached. The bottom groove of the bottom end of the irregular refractory brick in the upper layer is fastened to the top surface protrusion of the top surface of the irregular refractory brick in the lower layer. The irregular refractory brick in the upper layer and the irregular refractory brick in the lower layer are staggered and fastened. The side protrusion of the irregular refractory brick on the left side is inserted into the side groove of the irregular refractory brick on the right side, and so on. D. Lay a layer of fiber cotton on the surface between the template and the adjacent shaped refractory brick layer. This helps to eliminate the expansion of the castable and the refractory brick. Use mullite castable to grout the shaped refractory brick and template so that the space between the brick layers is filled with castable. E. After the brick layer has hardened, level the brick layer and lay a layer of fiber felt. F. Repeat the masonry work according to steps BE.

2. The construction method of the inner ring masonry structure of the C-type double-chamber kiln according to claim 1, characterized in that: The thickness of the fiber felt when laid flat is 10 mm.

3. The method for constructing the inner ring masonry structure of a C-type double-chamber kiln according to claim 1 or 2, characterized in that: Each layer of the template is at the same height as the brick segment layer of the shaped refractory brick, with a height of 2m-3m. Fiber felt with a thickness of 10mm is laid between the upper and lower layers of each brick segment layer; fiber felt with a thickness of 10mm is also laid between the upper and lower layers of each template.

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