Brick laying structure at the end of the combustion chamber of a chamber furnace type coke oven

Abstract

To provide brick masonry structure of a combustion chamber end part of a chamber-type coke oven, that suppresses narrowing of a kiln mouth of the coke oven.SOLUTION: A first masonry brick 1A has: side wall bricks 30 that configure a side wall of a furnace length direction X end of a combustion chamber 103; and a laufer end brick 31 that is a partition wall between a combustion chamber end flue 3a on an endmost in the furnace length direction of the combustion chamber and a coke oven chamber 102. Side wall bricks are formed with shoulder parts T for receiving a built-in part 31b that is one end side of the laufer end brick. The laufer end brick has a bending point Q at which inclination changes discontinuously in a substantially central portion of a combustion chamber end flue-side side surface, and an extended part 31y formed so as to protrude inward from the combustion chamber end flue toward the side wall brick side from the bending point, in a planar view viewed from a furnace top side. The laufer end brick has an extended joint surface v where the extended part joins the combustion chamber end flue-side side surface in addition to a built-in joint surface t where a built-in part joins the shoulder parts when combined with the side wall brick, and a surface of the built-in joint surface perpendicular to a furnace length direction is closer to a chamber end side than the extended joint surface.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present invention relates to a brick laying structure at the end of a combustion chamber of a chamber-type coke oven.

Background Art

[0002] In a coke oven, raw coal is carbonized to produce coke. The supply of raw coal, heating for coal carbonization, and extraction of coke after coal carbonization are repeated. The furnace body of the coke oven may be deformed due to thermal stress caused by temperature changes, coal expansion pressure during coal carbonization, side pressure during coke extrusion, etc., and the airtightness required for carbonization may not be maintained. Here, first, the structure of the chamber-type coke oven will be described, and then the furnace body deformation will be explained.

[0003] FIG. 1 is a schematic diagram for explaining an example of a chamber-type coke oven, where (A) is a partial side view, (B) is a partial plan view, and (C) is a partial front view (extruder side). In FIG. 1, X indicates the furnace length direction, Y indicates the furnace group length direction, and Z indicates the furnace height direction.

[0004] As shown in FIG. 1, in the upper part of the furnace body 101 of the chamber-type coke oven 100 (hereinafter simply referred to as "coke oven"), a plurality of elongated carbonization chambers 102 and combustion chambers 103 are alternately arranged in the furnace group length direction Y. A regenerator 104 is provided in the lower part. A plurality of charging ports 105 are provided on the top side of the carbonization chamber 102. Raw coal is supplied into the carbonization chamber 102 from these charging ports 105, and is indirectly heated and carbonized by the combustion heat of combustion gas in the adjacent combustion chamber 103 to produce coke.

[0005] On both sides of the carbonization chamber 102 in the furnace length direction X, there are coke ports 109 for taking out the produced coke. During the dry distillation process of coal, in order to seal the carbonization chamber 102, a furnace lid (not shown) is attached to the furnace frame 2 (see Fig. 2) to block the coke port 109. After dry distillation, the furnace lid is removed, an extruder (not shown) is arranged on one side of the coke port 109, and its extrusion ram is inserted into the carbonization chamber 102 to extrude the coke in the carbonization chamber 102, and it is recovered by a guide car arranged on the other side of the coke port 109. Although not shown here, in the combustion chamber 103, there are a plurality of combustion chamber flues 3 (such as the first flue 3a and the second flue 3b in Fig. 3) partitioned by a partition wall (the brick wall of the binder part 15 in Fig. 3) extending in the furnace group length direction Y.

[0006] The furnace body 101 is a brick-built structure of brick masonry. To prevent loosening due to repeated expansion and contraction, a tightening force (furnace tightening force) is applied to the furnace body 101 by the furnace tightening hardware and restrained. As shown in Fig. 1, outside the furnace of each combustion chamber 103 of the furnace body 101, at approximately the center in the furnace group length direction Y of each combustion chamber 103, a pair of backstays 106 (the backstay 106a on the extruder side and the backstay 106b on the guide car side) stand upright in the furnace height direction Z and are installed so as to face each other in the furnace length direction X. The backstay 106 is a highly rigid H-shaped steel, and to each of the backstays 106a and 106b, steel bars called cross tie rods 107, two each, are connected vertically in the furnace height direction Z, and springs 108 are attached. The furnace tightening force is due to the elastic force (restoring force) of this spring 108. The furnace tightening force of the spring 108 is transmitted to the backstay 106, and the furnace body 101 is tightened inward in the furnace length direction X. Hereinafter, the brick structure of the furnace body 101 and its tightening will be described with reference to the drawings.

[0007] The furnace body 101 of the coke oven 100 is constructed by alternately stacking two types of single-stage brick masonry structures (hereinafter referred to as "assembled bricks"), which are in a state where a plurality of bricks are assembled in a planar shape, in the furnace height direction. In order to avoid the vertical joints being continuous in the furnace height direction Z when constructed, two assembled bricks with different brick shapes and brick assembly methods are alternately stacked, so that the vertical joints (hereinafter simply referred to as "joints") are alternately offset for each stage.

[0008] Figure 2 is a partial cross-sectional view showing an outline of the configuration at the end of the coke oven 100 in the furnace length direction X. In Figure 2, (A) shows the brick structure of one of the two types of brick assemblies (hereinafter referred to as the first brick assembly 101A), and (B) shows the brick structure of the other of the two types of brick assemblies (hereinafter referred to as the second brick assembly 101B). Here, the description will be made only about the brick structure on the side where the extruder side backstay 106a is arranged, and the description of the guide car side backstay 106b side is omitted because it is substantially the same as that of the extruder side backstay 106a side.

[0009] As shown in Figure 2, a distance piece 4 and a protective plate 5 are arranged between the extruder side backstay 106a (hereinafter simply referred to as the backstay 106a) and the furnace wall of the combustion chamber 103 of the furnace body 101. The furnace tightening force transmitted to the backstay 106a is transmitted to the furnace body 101, which is a brick structure, through the distance piece 4 and the protective plate 5.

[0010] The protective plate 5 is a high-rigidity plate-shaped material that covers the outer surface of the furnace wall at the end in the furnace length direction X of the combustion chamber 103 and presses the entire side wall surface. The distance piece 4 is a rod-shaped steel material and is inserted substantially horizontally into the gap formed between the backstay 106a and the protective plate 5. The backstay 106a is bent with forces applied only at two locations, the upper end and the lower end, by the spring 108 (see Figure 1), and a gap is generated in the central portion thereof. Therefore, a plurality of distance pieces 4 having a thickness corresponding to the size of the gap are inserted in the furnace height direction. The contact area between the backstay 106a and the protective plate 5 is ensured to transmit a sufficient furnace tightening force to the side wall of the furnace body, and the furnace tightening force acts perpendicularly to the side wall. In the following description, the method of applying the furnace tightening force to the central portion in the furnace length direction of the combustion chamber of the coke oven using the distance piece 4 (DP) is referred to as the DP method.

[0011] Here, regarding the names of the respective parts of the furnace body 101 used in the following description, it will be described with reference to FIG. 3. As shown in FIG. 3(A), the outer wall side surface portion at the X-end in the furnace length direction of the combustion chamber 103 is called the side wall portion 10, and the bricks disposed in this portion are called side wall bricks 20, 30 (see FIGS. 2, 5, etc.). The partition wall portion separating the carbonization chamber 102 and the combustion chamber flue rows (combustion chamber flues 3a, 3b, …) is called the roof portion 12, and the bricks disposed in this portion are called roof bricks 22 (see FIG. 2, etc.). Also, the partition wall portion separating the combustion chamber flues 3 from each other is called the binder portion 15, and the bricks disposed in this portion are called binder bricks 25, 35 (see FIGS. 2, 5, etc.). Among the combustion chamber flues 3 (hereinafter simply referred to as flue 3), the one located at the outermost end (the outermost end in the furnace length direction) with the side wall portion 10 as the side wall is called the first flue 3a (or end flue 3a), and the one adjacent to it is called the second flue 3b. In this description, the side wall brick 20 refers to the bricks disposed in the side wall portion 10 that are joined to the roof portion 12 and face the end flue 3a.

[0012] Regarding the roof portion 12, as shown in FIG. 3(B), the portion K where the end flue 3a (the first flue) and the carbonization chamber 102 face each other is called the roof end portion 11, and the bricks disposed in this portion are called roof end bricks 21, 31 (see FIGS. 2, 5, etc.). Furthermore, in the roof portion 12, the portion within the extension line range S of the binder portion 15 is called the intersection portion 14.

[0013] Returning to FIG. 2, the structures of the first set of bricks 101A and the second set of bricks 101B of the furnace body 101 will be described. The first set of bricks 101A and the second set of bricks 101B that make up the furnace body 101 are each composed of a plurality of bricks assembled with a key-shaped joint surface, and the two sets of bricks 101A and 101B are configured such that they are inverted with respect to the central axis extending in the furnace length direction X. For the side wall portion 10, which is the side wall at the X end in the furnace length direction of the combustion chamber 103, one insulating brick 6 and four side wall bricks 20 (both ends are clay bricks and the two in between are silica bricks) are used. For the roof part 12 (including the roof end part 11) and the binder part 15, a plurality of silica bricks are used as the roof bricks 22 (including the roof end bricks 21) and the binder bricks 25.

[0014] The problems of the conventional furnace body 101 described above will be explained below. FIG. 4 is an explanatory diagram showing the secular deformation of the brick structure (state before operation start) of the first set of bricks 101A shown in FIG. 2(A). (A) shows a state where cracks have occurred at two locations of the roof end part 11, and (B) shows a state where the deformation has progressed due to the cracks and the furnace mouth 109 of the carbonization chamber 102 has narrowed. Note that since the secular deformation of the second set of bricks 101B, which has a configuration in which the first set of bricks 101A is inverted, is substantially the same as that of the first set of bricks 101A, the description thereof is omitted.

[0015] First, the generation of cracks will be described. As shown in Fig. 4(A), two longitudinal through-cracks C penetrating in the longitudinal direction (furnace height direction) occur at the roof end 11 of the furnace body 101 of the coke oven 100. The position of the longitudinal through-crack C is the position of the dotted line shown in Fig. 2. As shown in Fig. 2, it is the joint position of one of the first set of bricks 101A and the second set of bricks 101B at the joint of the roof end bricks 21, and the joint between the bricks causes joint opening due to a sudden temperature change during operation. Also, at the other roof end brick 21 of the first set of bricks 101A and the second set of bricks 101B, although it is a location deviated from the joint position, it is located directly above and below the opening of one of the roof end bricks 21. Therefore, due to the joint opening of one of the roof end bricks 21, a large shear force is applied to the other roof end brick 21, and longitudinal cracks are generated due to the shear stress. Finally, joints opening in the furnace height direction Z and longitudinal cracks continuously occur alternately and penetrate to form the longitudinal through-crack C.

[0016] Next, the narrowing of the kiln mouth will be described. As shown in Fig. 4(B), the acting point of the furnace clamping force by the backstay 106a is the center of the furnace circumference direction Y of the protective plate 5 of the coke oven 100. Therefore, the protective plate 5 is bent by being pushed inward only at the central part, and the furnace clamping force mainly acts on the central part of the side wall part 10 of the combustion chamber 103, and the four side wall bricks 20 joined by dovetail joints in the furnace circumference direction Y are pushed apart (black arrows). Also, as described above, the roof end brick 21 joined to the side wall brick 20 is divided by the longitudinal through-crack C and the restraining force in the furnace length direction X is reduced. Therefore, the side wall bricks 20 of the side wall part 10 assembled at the dovetail joint surface are forced outward by the furnace clamping force acting in the direction of rotation and protrude toward the adjacent carbonization chamber 102 side, and the roof end brick 21 in a divided state follows and also rotates and protrudes toward the carbonization chamber 102 side (white arrows). Due to the protrusion of the side wall bricks 20 and the roof end bricks 21, the kiln mouth 109 (see Fig. 1) of the carbonization chamber 102 provided between the two combustion chambers 103 is narrowed.

[0017] The occurrence of the above two cracks and the narrowing of the kiln mouth have the following problems. The part that protrudes into the carbonization chamber 102 due to the narrowing of the kiln mouth becomes the extrusion resistance of the extrusion ram when performing the coke extrusion operation. If the extrusion operation is forced, the lateral pressure applied to the furnace wall increases and causes collapse, so it is cut as an emergency measure. However, since the furnace wall becomes thinner due to cutting, there is a problem that the furnace wall strength decreases and the kiln mouth life becomes shorter. In addition, the part (hereinafter referred to as the divided brick) separated by the two cracks of the LOFFER end brick 21 has a weakened restraint force due to the division. Therefore, when a force is applied in the Y direction of the furnace group length from the carbonization chamber side due to coal expansion during carbonization or coke extrusion operation, there is a risk of falling off to the end flue 3a.

[0018] Here, the following technologies are disclosed as means for solving the problems of cracks and deformation of the coke oven body. Patent Document 1 discloses a technology related to the brick laying structure of the furnace wall bricks of the carbonization chamber and the combustion chamber flue for preventing thermal cracks, suppressing deformation, and realizing the long life of the furnace wall. This technology is in the brick laying structure of the furnace wall bricks of a coke oven having a LOFFER brick 22 which is a partition wall between the carbonization chamber and the combustion chamber and a binder brick 25 which is a partition wall between the combustion chamber flues. The end of the binder brick 25 in the furnace length direction sandwiching the combustion chamber flue is integrated with the LOFFER brick 22, and the brick is further installed in a point-symmetrical relationship also in the part facing the carbonization chamber on the opposite side. A brick in a form connecting the bricks is arranged in the binder part, and a ring-shaped brick unit is constituted by the respective bricks. The brick unit is installed every other flue of the combustion chamber, and the space therebetween is connected by a rectangular parallelepiped LOFFER brick 22. And the LOFFER brick 22 has a joint which is a vertical joint surface only within the extension line of the binder brick 25.

[0019] In addition, Patent Document 2 discloses a technology related to a tightening method that focuses on the point of action of the furnace tightening force by the backstay and can uniformly transmit the tightening force of the furnace body in a coke oven of the chamber furnace type in the height direction of the combustion chamber. This technology is arranged outside the furnace at both ends in the furnace length direction of each combustion chamber of the coke oven and is connected by cross tie rods installed at two locations close to the upper and lower ends in the height direction of the coke oven. A plurality of stages in the height direction and two pieces each in the furnace group direction of furnace tightening hardware are installed at the part of the combustion chamber side of the backstay that faces the combustion chamber. The furnace tightening force obtained by the furnace tightening springs provided at both ends of the cross tie rods is applied in the furnace length direction of the combustion chamber through the furnace tightening hardware, the door frames (furnace frames) arranged at both ends in the furnace length direction of the combustion chamber, and the protective plates. In the method for tightening the furnace body of the coke oven, the furnace tightening transmission device penetrates an opening provided between the door frame and the furnace tightening hardware of the backstay, and the furnace tightening force is transmitted from the furnace tightening hardware to the door frame through the furnace tightening transmission device.

Prior Art Documents

Patent Documents

[0020]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0021] The technology described in Patent Document 1 relates to the partition walls between the carbonization chamber and the combustion chamber and between the combustion chamber flues, and does not examine the brickwork structure at both ends in the furnace length direction of the combustion chamber (hereinafter also referred to as the end brickwork structure), and does not solve the problem of the narrowing of the port of the carbonization chamber due to the phenomenon of the bricks protruding.

[0022] In the technology described in Patent Document 2, a furnace tightening transmission device is used to transmit the furnace tightening force to both ends of the protection plate in the longitudinal direction of the furnace group. However, since the structure is complex and the number of parts is large, it is costly, and there is a problem that the workload of adjusting the spring for maintaining an appropriate furnace tightening force is large. Furthermore, in the case of an existing coke oven, there may be a situation where a space for arranging the furnace tightening transmission device cannot be secured due to the positional relationship with the rails of the moving machine (pusher and guide car). Also, even when rebuilding a coke oven, in order to provide a space for arranging the furnace tightening transmission device, it is necessary to relocate the moving machine rails. However, since the operation continues while continuously using a shared moving machine in coke ovens other than the one to be rebuilt in order not to stop the supply of coke to the blast furnace, the relocation is not easy and sharing the moving machine becomes impossible. Additionally, it is conceivable to reduce the coke oven volume for equipment installation, but the production volume of coke will decrease.

[0023] An object of the present invention is to provide a bricklaying structure at the end of the combustion chamber of a chamber-type coke oven that can suppress narrowing of the furnace mouth of the coke oven regardless of the transmission position of the furnace tightening force.

Means for Solving the Problems

[0024] That is, the gist of the present invention is as follows. (1) It includes a first set of bricks and a second set of bricks formed by arranging a plurality of bricks in a planar shape, The first set of bricks includes sidewall bricks that form the sidewall at the end of the furnace length direction of the combustion chamber, and Löffer end bricks that are partition walls between the combustion chamber end flue at the extreme end of the furnace length direction of the combustion chamber and the carbonization chamber, On the sidewall bricks, a shoulder for receiving an incorporated part, which is one end side of the Löffer end bricks, is formed (at the carbonization chamber side end of the side surface on the combustion chamber end flue side), The Löffer end bricks have a bending point where the inclination changes discontinuously at approximately the center of the side surface on the combustion chamber end flue side in a plan view seen from the furnace top side, and an extension part formed to protrude inward of the combustion chamber end flue from the bending point toward the sidewall brick side, When the Loewen end brick is combined with the side wall brick, in addition to the built-in joint surface where the built-in part joins the shoulder, the extension part has an extension joint surface that joins the side surface on the flue side of the combustion chamber end, The surface perpendicular to the furnace length direction of the built-in joint surface is on the furnace end side in the furnace length direction rather than the extension joint surface, and is the brick laying structure at the end of the combustion chamber of a chamber furnace type coke oven. (2) The Loewen end brick is formed such that the width in the furnace group length direction in plan view becomes wider as it goes from the bending point toward the extension joint surface, and is the brick laying structure at the end of the combustion chamber of the chamber furnace type coke oven according to (1). (3) The extension joint surface is located substantially on the same straight line in plan view as the side surface on the flue side of the combustion chamber end of the side wall brick, and is the brick laying structure at the end of the combustion chamber of the chamber furnace type coke oven according to (1) or (2). (4) The bending point of the first assembled brick is at a position that substantially overlaps with the joint of the second assembled brick in the furnace height direction, and is the brick laying structure at the end of the combustion chamber of any one of the chamber furnace type coke ovens according to (1) to (3). (5) In the first assembled brick, the side wall at the furnace length direction end of the combustion chamber is composed of two side wall bricks divided in the furnace group length direction, The joint surface of the two side wall bricks has a concavo-convex fitting part, The joint surface of the two side wall bricks is substantially planar except for the concavo-convex fitting part, and is the brick laying structure at the end of the combustion chamber of any one of the chamber furnace type coke ovens according to (1) to (4).

Advantages of the Invention

[0025] In the present invention, by forming an extension part on the Loewen end brick 21 of the first assembled brick, it is configured such that there is only one crack entering the Loewen end part, and narrowing of the kiln mouth is suppressed.

Brief Description of the Drawings

[0026]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

MODE FOR CARRYING OUT THE INVENTION

[0027] The present inventors have earnestly studied through structural analysis and actual machine verification, and consider that the phenomenon of the narrowing of the coke oven mouth occurs due to the combined action of the furnace tightening force acting on the center of the side wall of the combustion chamber by the DP method and the occurrence of two cracks in the furnace body (brick structure). And, as a measure for improving the narrowing of the coke oven mouth, considering the case where it is difficult to change the structure of the side (hardware) that applies the furnace tightening force to the furnace body due to space constraints, the structure on the furnace body side was studied. The present invention suppresses the occurrence of segmental bricks that may cause narrowing of the coke oven mouth, sinking or falling off to the combustion chamber flue side by changing the brick stacking structure.

[0028] The inventors found that the problem with the conventional brick stacking structure shown in FIG. 2 is a two-crack structure with two cracks entering the Loifer end 11. This two-crack structure is due to the fact that the side wall portion 10 (excluding the heat insulating bricks 6) of the combustion chamber 103 is divided into four parts (composed of four bricks), resulting in a large number of joints and low rigidity, and because the joint division is of the key type, it is easy to promote the rotation of the side wall brick 20. Therefore, as countermeasures, it was decided to reduce the number of joints by increasing the size of the side wall brick 20 and improve the rotational rigidity by changing the joint shape. Furthermore, by changing the shape of the Loifer end brick 21, the cracks generated at the Loifer end 11 are made into one (single-crack structure), and by increasing the furnace tightening force transmission efficiency by widening the side wall portion side, it was considered to suppress the narrowing of the kiln mouth. Although it is ideal that no cracks occur in the furnace body 101, relatively low-temperature coal is charged into the carbonization chamber 102 after coke production, and stress due to thermal shrinkage is applied to the furnace body 101. Therefore, it is difficult to completely prevent the occurrence of cracks in the furnace body 101 during operation.

[0029] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In this specification and the drawings, for components having substantially the same functional configuration, the same name or reference numeral will be appropriately given to omit duplicate explanations.

[0030] 〔Brick Stacking Structure at the Combustion Chamber End: Embodiment 1〕 As an example of the present invention, the bricklaying structure at the combustion chamber end of the furnace body 101 of the chamber furnace type coke oven 1 includes two types of single-layer bricklaying structures (the first assembled bricks 1A and the second assembled bricks 1B) formed by arranging a plurality of bricks in a planar manner, and these are alternately stacked in the furnace height direction Z. The first assembled bricks 1A include the sidewall bricks 30 that form the sidewall of the combustion chamber 103 at the longitudinal end in the furnace length direction, the Loeffler end bricks 31 that are the partition wall between the combustion chamber end flue 3a at the outermost end in the furnace length direction X of the combustion chamber 103 and the carbonization chamber 102, and the connecting bricks 36 that are the partition wall between the combustion chamber end flue 3a, the adjacent combustion chamber flue 3b, and the carbonization chamber 102. The sidewall bricks 30 and the connecting bricks 36 each have a shoulder T that receives one end side and the other end side of the Loeffler end bricks 31, respectively. The side surface of the Loeffler end bricks 31 on the combustion chamber end flue side has a bending point Q where the inclination discontinuously changes at a substantially central portion in plan view as viewed from the furnace top side, and the Loeffler end bricks 31 are formed such that, in plan view, the width in the furnace length direction Y (the length of h in FIG. 5 in Embodiment 1) at the position of the bending point Q (hereinafter also referred to as the boundary Q) is smaller than the width in the furnace length direction Y (the lengths of v and w in FIG. 5 in Embodiment 1) at the position of the joint surface (the extended joint surface v described later) with the side surface of the sidewall bricks 30 on the combustion chamber end flue side. Here, the combustion chamber end means the group of bricks that form the peripheral wall of the end flue 3a of the combustion chamber 103.

[0031] FIG. 5 shows the bricklaying structure at the combustion chamber end of the chamber furnace type coke oven 1 according to Embodiment 1 which is an example of the present invention. FIG. 5(B) is a schematic diagram showing the configuration of one type of assembled bricks (hereinafter referred to as the first assembled bricks 1A), and FIG. 5(C) is a schematic diagram showing the configuration of the other type of assembled bricks (hereinafter referred to as the second assembled bricks 1B). Also, FIG. 5(A) is an explanatory diagram for explaining the shapes of the three bricks 30, 31, and 36 located on the upper side of the paper surface among the first assembled bricks 1A shown in FIG. 5(B). Note that FIG. 5 shows the state (planar view shape) as viewed from the furnace top side, and the planar view shape and the cross-sectional shape of each brick are substantially the same. Also, for the sake of convenience in explanation, the side on which the traveling machine rails are arranged in the furnace length direction X (the left side in FIG. 5) is defined as the outer side, and the central side of the combustion chamber on the opposite side (the right side in FIG. 5) is defined as the inner side.

[0032] As shown in FIGS. 5(B) and 5(C), in the first set of bricks 1A and the second set of bricks 1B, the clay bricks 7 are arranged on both sides of the heat insulating bricks 6, and the furnace tightening force is transmitted to the side wall bricks 30 at the X-end in the furnace length direction of the combustion chamber 103 through the heat insulating bricks 6 and the clay bricks 7 which are heat insulating members. Silica bricks are used for the side wall bricks 30, 30Y, the roof end bricks 31, the binder bricks 35, the connecting bricks 36, and the corner bricks 37 that constitute the furnace body main body. This is because the temperature regions to which the bricks are exposed differ depending on the positions where they are arranged in the coke oven 1, and the characteristics of the bricks (such as the thermal expansion coefficient, the thermal conductivity, and the wear resistance) are considered. Also, by using the same silica bricks for the furnace body main body, the deformation of the furnace body main body due to the expansion difference of the bricks is reduced. Note that the furnace tightening force acts mainly on the central portion of the side wall portion 10 of the combustion chamber 103, as in the conventional example.

[0033] (Configuration of the first set of bricks) First, the configuration of the first set of bricks 1A will be described. As shown in FIGS. 5(A), (B) and FIG. 3, in the first set of bricks 1A, the side wall portion 10 of the combustion chamber 103 is composed of two side wall bricks 30 having different lengths assembled (divided in the furnace length direction Y) in the furnace length direction Y. At the joint portion, which is the joint surface of the two side wall bricks 30, there is an uneven fitting portion P (hereinafter simply referred to as the uneven fitting portion P), which is a portion where a concave groove extending in the furnace height direction Z and having a semi-circular shape in plan view and a convex strip are fitted together, formed at the central portion in the furnace length direction. The joint surface of the two side wall bricks 30 is substantially flat in portions other than this uneven fitting portion P, and the two side wall bricks 30 are combined by the uneven fitting portion P. Each side wall brick 30 is formed such that its outer side surface conforms to the shapes of the adjacent heat insulating bricks 6 and clay bricks 7, and is combined with the clay brick 7 by the uneven fitting portion P. Further, the inner side surface of the side wall brick 30 is substantially flat, and at the end portion on the coke oven chamber 102 side, a shoulder T (hereinafter simply referred to as the shoulder T), which is an L-shaped step portion formed by notching a substantially rectangular portion in plan view at the corner portion on the Löfgrens end brick 31 side, is formed to receive the incorporation portion 31b of the Löfgrens end brick 31. In the following description, the joint surface where the incorporation portion 31b of the Löfgrens end brick 31 joins the shoulder T is referred to as the incorporation joint surface t.

[0034] The two lower end bricks 11 each consist of one lower end brick 31. The lower end brick 31 comprises a main body part 31x having a substantially rectangular shape in plan view and an extended part 31y having a substantially right-angled triangular shape in plan view. The main body part 31x consists of built-in parts 31b which are both end parts in the furnace length direction X and a main body middle part 31a which is the part sandwiched between the two built-in parts 31b. Each built-in part 31b has substantially the same shape and is respectively received by the shoulder part T of the side wall brick 30 and the shoulder part T of the connecting brick 36, and is combined by the uneven fitting part P. The extended part 31y is formed on the side face of the end flue 3a side of the main body middle part 31a so as to project inward of the end flue 3a in the region on the side wall brick 30 side with the substantially center in the furnace length direction X as the boundary Q. The columnar extended part 31y having a substantially right-angled triangular cross section has the hypotenuse side face n facing the end flue 3a. Also, the side wall brick side side face v which is the short adjacent side part is located on substantially the same plane (substantially on the same straight line in plan view) as the side wall brick side side face w of the main body middle part 31a, and is a joint surface that abuts against the end flue 3a side side face u of the side wall brick 30 in a state where the lower end brick 31 is received by the side wall brick 30. In the following description, the joint surface where the extended part 31y of the lower end brick 31 abuts against the combustion chamber end flue side side face of the side wall brick 30 is referred to as the extended joint surface v.

[0035] Also, the end flue 3a side side face of the extended part 31y is substantially in a C-shape in plan view as viewed from the furnace top side, and the boundary Q at the substantially central part is a bending point where the inclination changes discontinuously. The width of the lower end brick 21 in the furnace circumferential length direction becomes wider toward the side wall brick side from the bending point, and the region on the side wall brick side (the hypotenuse side face n) with the bending point as the boundary is an inclined surface having a constant inclination angle with respect to the vertical plane in the furnace circumferential length direction Y. The width of the lower end brick 31 (excluding the built-in part 31b on the side wall part side) in the furnace circumferential length direction Y has a constant size for the inner part (right side part) with the substantially center in the furnace length direction of the main body middle part 31a as the boundary Q (crack initiation location), and the outer part (left side part) increases at a substantially constant rate toward the extended joint surface v which is the joint surface with the side wall brick 30.

[0036] Here, the surface of the built-in joint surface t perpendicular to the furnace length direction is located on the furnace end side in the furnace length direction X rather than the extended joint surface v. That is, the built-in part 31b, which is one end side of the main body part 31x of the Loifer end brick 31, is built in so as to enter the side wall brick 30 side (side wall part 10). The length e in the furnace length direction X of the shoulder T of the side wall brick 30 that receives the built-in part 31b of the Loifer end brick 31 (the combined length of the Loifer end brick 31 and the side wall brick 30) is preferably 20% or more and 40% or less of the width f (the length in the furnace length direction X) at the end in the furnace group length direction Y of the side wall brick 30 (the coke oven 102 side), and more preferably 25% or more and 35% or less. If it is less than 20%, the amount of combination of the built-in part 31b and the shoulder T becomes small, and it becomes difficult to hold the Loifer end brick 31 so as not to be pushed out. Also, if it is more than 40%, the width on the side wall brick 30 side becomes too small and the rigidity of the side wall brick 30 decreases.

[0037] Also, in the Loifer end brick 31, the maximum width g (the maximum length in the furnace group length direction Y) of the extended part 31y is preferably 35% or more and 65% or less of the width h (the length in the furnace group length direction Y) of the main body part 31x, and more preferably 40% or more and 60% or less. If it is less than 35%, the purpose of the furnace tightening force transmission effect from the side wall brick 30 to the Loifer end brick 31 cannot be achieved. Also, if it is more than 65%, the heat transfer amount at the end of the coke oven 102 decreases due to the increase in the thickness of the Loifer end brick 31, and there is a risk that the coke will be in an uncarbonized state.

[0038] The binder part 15 is composed of a substantially inverted U-shaped built-up brick (hereinafter simply referred to as the U-shaped built-up brick 40X) in plan view, which consists of two connecting bricks 36 and a binder brick 35 sandwiched between both connecting bricks 36. The connecting brick 36 is substantially L-shaped in plan view and is an L-shaped brick that integrates a part of the binder part 15 and a part of the roof part 12. The connecting brick 36 includes the intersection part 14, a part of the binder part 15 that is in contact with the intersection part 14, and a part of the inner roof part 12 that is in contact with the intersection part 14, and is a partition wall that separates the end flue 3a (the first flue), the second flue 3b adjacent to this, and the carbonization chamber 102. At a position corresponding to the roof part 12 (corresponding to the intersection part 14) at the L-shaped corner of the connecting brick 36, a shoulder T is formed that can receive the built-in part 31b of the roof end brick 31. In addition, an R (radius) is formed at the inner corner of the L-shaped corner. By having the R part, stress concentration is alleviated and the rigidity against bending is also increased. In the two connecting bricks 36, the lengths in the furnace length direction X of the portions corresponding to the roof part 12 are the same, but the lengths in the furnace width direction Y of the portions corresponding to the binder part 15 are different. Therefore, the binder brick 35, which is substantially I-shaped in plan view and sandwiched between both connecting bricks 36, has its center at a position deviated from the center line of the combustion chamber 103.

[0039] (Configuration of the second built-up brick) Next, the configuration of the second built-up brick 1B will be described. As shown in Fig. 5(C), in the second set of bricks 1B, at the combustion chamber end (the group of bricks constituting the peripheral wall of the end flue 3a of the combustion chamber 103, i.e., the group of bricks located in the side wall portion 10, the roof end portion 11, the intersection portion 14, and the binder portion 15), it is configured by combining two substantially U-shaped bricks in plan view (U-shaped bricks 40X, Y) facing each other. Among the two U-shaped bricks 40X, Y, the one arranged on the inner side (the right side in the drawing) is the U-shaped brick 40X, and the U-shaped brick 40X of the first set of bricks 1A is arranged by rotating 180 degrees around the intersection of the center line of the combustion chamber 103 and the center line of the binder brick 35. The other U-shaped brick 40Y is composed of two corner bricks 37 and a side wall brick 30Y sandwiched between the two corner bricks 37. The corner brick 37 is substantially L-shaped in plan view and is an L-shaped brick integrating a part of the side wall portion 10 and a part of the roof portion 12. Also, an R (radius) is formed at the inner angle of the L-shaped corner. The side wall brick 30Y is substantially I-shaped in plan view and is combined with the two corner bricks 37 by the uneven fitting portion P. Also, the outer side (the left side in the drawing) side surface of the U-shaped brick 40Y is formed along the shapes of the adjacent heat insulating bricks 6 and clay bricks 7, and the corner brick 37 is combined with the clay brick 7 by the uneven fitting portion P. The U-shaped brick 40X and the U-shaped brick 40Y are combined by the uneven fitting portion P.

[0040] (Joint position of the first set of bricks and the second set of bricks) Next, the relationship of the joint positions when the first set of bricks 1A and the second set of bricks 1B are stacked will be described. Fig. 6 is a schematic view showing a state where the second set of bricks 1B is stacked on the first set of bricks 1A and viewed from the furnace top direction. The joint positions of the first set of bricks 1A are indicated by broken lines, and the visible parts of the first set of bricks are indicated by hatching. As shown in Fig. 6, at the combustion chamber end, the joints of the first set of bricks 1A and the joints of the second set of bricks 1B are configured not to overlap. Regarding the joint M, which is the joint surface between the U-shaped brick 40Y and the U-shaped brick 40X of the second set of bricks 1B, it is provided at a position overlapping the boundary Q (crack-inducing location) where the width in the furnace length direction Y of the roof end brick 31 of the first set of bricks 1A changes.

[0041] 〔Features and Effects of Brick Laying Structure〕 In the brick laying structure at the end of the combustion chamber of the chamber furnace type coke oven of the present invention, it includes a first set of bricks and a second set of bricks formed by arranging a plurality of bricks in a plane. The first set of bricks has a side wall brick that constitutes the side wall at the end in the furnace length direction of the combustion chamber, and a Löffer end brick that is a partition wall between the combustion chamber end flue at the outermost end in the furnace length direction of the combustion chamber and the carbonization chamber. On the side wall brick, (at the end of the carbonization chamber side on the side surface of the combustion chamber end flue side), a shoulder for receiving an incorporated part, which is one end side of the Löffer end brick, is formed. The Löffer end brick has, in a plan view as viewed from the furnace top side, a bending point where the inclination discontinuously changes at approximately the center of the side surface on the combustion chamber end flue side, and an extended part formed to protrude inward of the combustion chamber end flue from the bending point toward the side wall brick side. The Löffer end brick, when combined with the side wall brick, has an extended joint surface where the extended part joins the side surface on the combustion chamber end flue side, in addition to the incorporated joint surface where the incorporated part joins the shoulder. It is an essential configuration that the plane perpendicular to the furnace length direction of the incorporated joint surface is on the furnace end side in the furnace length direction rather than the extended joint surface. (Joint Quantity and Joint Shape) In the brick laying structure at the end of the combustion chamber of this embodiment, as described above, in the first set of bricks 1A, the side wall brick 30 used for the side wall part 10 is enlarged and composed of two side wall bricks 30. Thereby, the joint quantity of the side wall part 10 becomes one, so the rigidity is improved. Also, by changing the joint division of the two side wall bricks 30 from a key-type joint surface where rotational force is likely to be applied to a joint surface provided with a concave-convex fitting part P on a plane, the rigidity is further improved, and it suppresses the side wall brick 30 and the Löffer end brick 31 from rotating and causing a squeezing-out phenomenon.

[0042] (Single Crack Structure) In this embodiment, as a bricklaying structure, a single crack is configured to occur at approximately the center in the furnace length direction X at the Loever end portion 11 at the end of the combustion chamber. Specifically, in the first set of bricks 1A, a crack induction location is formed at the center of the Loever end brick 31, and both ends thereof are combined so as to bite into adjacent bricks to suppress the occurrence of cracks. Also, considering the crack induction location and the joint positions of the first set of bricks 1A, the shape and joint positions of the bricks of the second set of bricks 1B are determined.

[0043] Hereinafter, the bricklaying structure with a single crack structure and its effects will be described in detail. The crack induction location at the Loever end portion 11 of the first set of bricks 1A is the boundary Q which is the start point of the width expansion in the furnace length direction Y formed at approximately the center in the furnace length direction of the Loever end brick 31 by the expansion portion 31y. By forming the side surface on the end flue 3a side of the Loever end brick 31 in a substantially U-shape in plan view, stress concentrates at the boundary Q which is the bending point, making it easier for cracks to occur.

[0044] On the other hand, one end side of the Loever end brick 31 of the first set of bricks 1A is configured to be received so that the built-in portion 31b bites into the shoulder T of the adjacent side wall brick 30. Also, the expansion portion 31y of the Loever end brick 31 is configured to abut against the side surface on the end flue 3a side of the side wall brick 30. By enlarging the side wall brick 30, a shoulder T of a size capable of receiving the entire one end portion side (built-in portion 31b) of the main body portion 31x of the Loever end brick 31 can be formed, and the Loever end brick 31 can be firmly held.

[0045] In addition, the roof-end brick 31 of the first brick group 1A is configured such that the width in the furnace length direction Y is not constant in a plan view and the side-wall-brick 30 side is widened so that the contact area with the side-wall brick 30 increases. By forming the extension part 31y on the main body part 31x, the contact area increases by the area of the extended joint surface v. By increasing the contact area of the roof-end brick 31 that contacts the side-wall brick 30, the transmission efficiency of the furnace clamping force acting on the side-wall brick 30 to the roof part 12 can be improved, and the restraining force of the bricks of the entire furnace body 101 can be strengthened. Note that the shape of the roof-end brick 31 is not limited to the above, and any configuration may be used as long as it has a bending point provided so that stress is concentrated and an extension part formed so that the contact area with the side-wall brick 30 increases.

[0046] The other end side of the roof-end brick 31 of the first brick group 1A is configured to be received so that the built-in part 31b bites into the shoulder T of the connecting brick 36 adjacent thereto. Since the connecting brick 36 is an L-shaped brick that integrates a part of the roof part 12 including the intersection part 14 and a part of the binder part 15, a shoulder T of a size that can receive the entire other end part side (built-in part 31b) of the main body part 31x of the roof-end brick 31 can be formed, and the roof-end brick 31 can be firmly held. In addition, the connecting brick 36, which is an L-shaped brick, is combined with the adjacent bricks at two positions at both ends thereof, and can support a large force applied from the roof-end brick 31 even at the shoulder T formed at the intersection part 14, which is a corner part.

[0047] In the brickwork structure, the crack initiation location of the roof-end brick 31 of the first set of bricks 1A overlaps with the joint between the connecting brick 36 and the corner brick 37 of the second set of bricks 1B (see the dashed line in FIGS. 5(B) and 5(C)). Therefore, longitudinal through-cracks that penetrate the first set of bricks 1A and the second set of bricks 1B in the furnace height direction Z are likely to occur at the crack initiation location of the first set of bricks 1A. Also, in the brickwork structure, the location that overlaps with the joint of the roof-end brick 31 of the first set of bricks 1A is the L-shaped corner part of the connecting brick 36 or the corner brick 37 in the second set of bricks 1B, and it is away from the joint position of the connecting brick 36 and the corner brick 37. Therefore, cracks are less likely to occur at the joint location of the roof-end brick 31 of the first set of bricks 1A.

[0048] With the brickwork structure of the first set of bricks 1A and the second set of bricks 1B and the bricklaying structure of the first set of bricks 1A and the second set of bricks 1B as described above, it is possible to prevent the occurrence of split bricks (a part of the roof-end brick 31) with the number of cracks being one, and suppress the narrowing of the kiln mouth. Also, by forming the expansion part 31y on the roof-end brick 31 of the first set of bricks 1A and expanding the joint area with the sidewall brick 30, the furnace clamping force acting on the sidewall brick 30 can be efficiently transmitted. The restraint force of the bricks arranged in the roof part 12 of the furnace body 101 can be increased, and the deformation of the furnace body 101 including the narrowing of the kiln mouth can be suppressed. The depression and falling off of the split bricks with weak restraint force can also be suppressed.

[0049] 〔Bricklaying Structure at the End of the Combustion Chamber: Modified Example〕 Next, the modified example will be described with reference to two drawings. FIG. 7 shows the bricklaying structure at the end of the combustion chamber of the chamber-type coke oven 1x, which is a modified example of Embodiment 1 that is an example of the present invention. (A) is an explanatory diagram for explaining the shapes of two bricks that constitute the first set of bricks, and (B) is a schematic diagram showing the configuration of the first set of bricks 1C. In FIG. 7, in order to show the changed parts from the configuration of the first set of bricks 1A in Embodiment 1, the configuration before the change (brick shape and joint position) is shown by a two-dot chain line. Also, since the configuration of the second set of bricks of the chamber-type coke oven 1x is the same as that of the second set of bricks 1B in Embodiment 1, the illustration and description are omitted, and only the configuration different from the first set of bricks 1A in Embodiment 1 will be described. FIG. 8 is a schematic diagram showing a state in which the second set of bricks 1B is stacked on the first set of bricks 1C and viewed from the furnace top direction for the chamber-type coke oven 1x which is a modified example. The hidden joint position of the first set of bricks 1A is shown by a dashed line, and the visible parts and joint positions of the first set of bricks are shown by hatching and solid lines.

[0050] As shown in Fig. 7, in the first set of bricks 1C of the modified example and the first set of bricks 1A of the first embodiment, the positions of the joint surfaces (built-in joint surface t and extended joint surface v) between the side wall bricks 30 and the roof end bricks 31 are different, and the first set of bricks 1C is configured such that the joint surface of the first set of bricks 1A is moved inward in the furnace length direction X. Specifically, in the first embodiment, the extended joint surface v was provided at the boundary between the side wall portion 10 and the roof end portion 11 (see Fig. 3(B)), but in the modified example, the extended joint surface v is provided at a position included in the roof end portion 11, and each side wall brick 30z arranged in the side wall portion 10 is a J-shaped brick composed of a part of the side wall portion 10 and a part protruding toward the roof end portion 11 side. The side surface on the end flange 3a side corresponding to the roof end portion 11 of the side wall brick 30z is located on the extension plane of the side surface on the end flange 3a side of the roof end brick 31, forming one inclined surface. In the modified example, although the positions of the joint surfaces between the side wall bricks 30 and the roof end bricks 31 are different, the basic structure is the same as that of the first embodiment 1, and the same operational effects as those of the first embodiment 1 can be achieved. An R (radius) is formed at the inner corner of the J-shaped corner of the side wall brick 30z. By forming the R portion, stress can be dispersed. Note that since the side wall brick 30 is provided such that the shoulder T is cut out at the joint portion with the roof end brick 31, the portion that abuts against the extended portion 31y (extended joint surface v) of the roof end brick 31 is a protrusion. In order to maintain rigidity, it is preferable to adjust the position of the joint surface and the inclination angle of the inclined surface so that the width of this protrusion is equal to or greater than a predetermined width.

[0051] [Verification by Structural Analysis] Regarding the brick structure of the first set of bricks, numerical structural analysis (2D FEM analysis) was performed using a 2D model to verify its effect. Regarding the set analysis conditions and boundary conditions, the consistency with the analysis results and actual phenomena in a 3D model was confirmed in advance. Analysis was performed on two cases, the first set of bricks 101A of the conventional example and the first set of bricks 1A of Embodiment 1. A furnace tightening force of 1 kgf / cm2 and a side pressure of 0.1 kgf / cm2 were applied to the combustion chamber 103, and the maximum tensile stress and the maximum joint opening amount at the joint portion between the side wall bricks 30 and the roof end bricks 31 were taken as the evaluation targets. As a result of the analysis, the maximum tensile stress of Embodiment 1 was 42% of that of the conventional example, and the maximum joint opening amount was 58% of that of the conventional example. It was verified that both values decreased significantly compared to the conventional example, and the effect of suppressing the narrowing of the kiln mouth could be expected.

[0052] As described above, the preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, but the present invention is not limited to such examples. It is obvious that those having ordinary knowledge in the technical field to which the present invention pertains can conceive of various modification examples or correction examples within the scope of the technical idea described in the claims, and it is naturally understood that these also belong to the technical scope of the present invention. In the above-described embodiment, the configuration in which a furnace tightening force acts on the central portion in the furnace length direction of the combustion chamber of the coke oven was exemplified, but the present invention is not limited to this, and it is also possible to apply it to a configuration in which a furnace tightening force acts on both end portions in the furnace length direction.

Explanation of reference numerals

[0053] 1,1x / 100… Coke oven, 101… Furnace body, 1a,1c / 101a… First set of bricks, 1b / 101b… Second set of bricks, 102… Carbonization chamber, 103… Combustion chamber, 104… Regenerator, 106… Backstay (106a Extruder side backstay, 106b Guide car side backstay), 107… Cross tie rod, 108… Spring, 3… Flue (3a First flue (end flue), 3b Second flue), 5… Protection plate, 6… Heat insulation brick, 7… Clay brick, 10… Side wall part, 11… Loifer end part, 12… Loifer part, 14… Intersection part, 15… Binder part, 20,30… Side wall bricks, 21,31… Loifer end bricks, 22… Loifer bricks, 25,35… Binder bricks, 31x… Main body part (31a Middle part of the main body, 31b Incorporation part), 31y… Expansion part, 36… Connecting brick, 37… Corner brick, 40X,40Y… U-shaped bricks, C… Longitudinal crack, M… Joint, P… Concave-convex fitting part, Q… Buckling point (boundary), T… Shoulder part, X… Furnace length direction, Y… Furnace width direction, Z… Furnace height direction

Claims

1. It includes a first set of bricks and a second set of bricks formed by arranging a plurality of bricks in a planar manner, The first set of bricks includes sidewall bricks that form the sidewalls at the ends of the combustion chamber in the furnace length direction, and Löfner end bricks that are partition walls between the combustion chamber end flue at the extreme end in the furnace length direction of the combustion chamber and the carbonization chamber, On the sidewall bricks, (at the end of the carbonization chamber side on the side surface of the combustion chamber end flue), a shoulder is formed to receive an incorporation part that is one end side of the Löfner end bricks, In a plan view as viewed from the furnace top side, the Löfner end bricks have a bending point where the inclination changes discontinuously at a substantially central portion of the side surface on the combustion chamber end flue side, and an extension part formed to project inward of the combustion chamber end flue from the bending point toward the sidewall bricks side, The Löfner end bricks have, at the combination part with the sidewall bricks, in addition to an incorporation joint surface where the incorporation part joins the shoulder, an extension joint surface where the extension part joins the side surface on the combustion chamber end flue side, The plane perpendicular to the furnace length direction of the incorporation joint surface is on the furnace end side in the furnace length direction compared to the extension joint surface, The second set of bricks arranges a U-shaped set of bricks (hereinafter referred to as "U-shaped assembled bricks") at the ends of the combustion chamber in the furnace length direction of the chamber furnace such that the tips of the U-shape face the inside of the furnace. The U-shaped assembled bricks have two corner bricks, and the corner bricks are substantially L-shaped in plan view, A brick assembly structure at the end of the combustion chamber of a chamber furnace type coke oven.

2. The Löfner end bricks are formed such that the width in the furnace length direction in plan view becomes wider as it goes from the bending point toward the extension joint surface. The brick assembly structure at the end of the combustion chamber of the chamber furnace type coke oven according to Claim 1.

3. The brick assembly structure at the end of the combustion chamber of the chamber furnace type coke oven according to Claim 1 or Claim 2, wherein the extension joint surface is located substantially on the same straight line in plan view as the side surface of the sidewall bricks on the combustion chamber end flue side.

4. The bending point of the first set of bricks is at a position that substantially overlaps with the joint of the second set of bricks in the furnace height direction. The brick assembly structure at the end of the combustion chamber of the chamber furnace type coke oven according to any one of Claims 1 to 3.

5. In the first set of bricks, the sidewalls at the ends of the combustion chamber in the furnace length direction are composed of two sidewall bricks divided in the furnace length direction, The joint surface of the two sidewall bricks has a concavo-convex fitting part, The joint surfaces of the two side wall bricks are substantially planar except for the concavo-convex fitting portions, and the brick laying structure at the end of the combustion chamber of the chamber furnace type coke oven according to any one of claims 1 to 4.

Images