JP5570012B2 - Thermal expansion absorption structure of the furnace wall - Google Patents

Description

  The present invention relates to a thermal expansion absorption structure for a furnace wall in a cylindrical furnace.

  When absorbing the thermal expansion of iron shell or refractory in a vertical cylindrical furnace lined with a refractory on the inner surface of the iron skin, an expansion allowance is usually provided according to the expected expansion amount, but thermal expansion is high in the cylindrical furnace. It may occur not only in the horizontal direction but also in the horizontal direction.

  For example, FIG. 6 shows a case where the connecting pipe 5 is connected to the outlet side of the cylindrical furnace 1. The cylindrical furnace 1 and the connecting pipe 5 are formed by lining a furnace wall refractory 2 on the inner surface of the iron shell 3. In this case, in order to absorb the thermal expansion in the height direction of the cylindrical furnace 1 and the thermal expansion in the horizontal direction of the connecting pipe 5, the thermal expansion absorption part 4 is provided.

  FIG. 4 shows a conventional example of the thermal expansion absorber 4. Clearances A are provided as expansion allowances in the height direction and B are provided as expansion allowances in the horizontal direction, and these gaps are filled with a contractible refractory wool 4b. In addition, the upper and lower iron skins 3 are connected to each other by the heat-resistant cloth 4c at the outer portion of the iron skin 3, and gas sealing is performed while allowing free movement relative to the relative movement of the upper and lower iron skins 3.

  However, in this conventional thermal expansion absorption structure, because the expansion allowance A is communicated to the inside of the furnace, especially in a furnace that handles high-temperature gas with a lot of dust, dust enters the same part and is compressed when the furnace is shut down. The expansion and contraction function gradually disappears, and a large expansion force acts on the iron skin and the refractory. This expansion force leads to refractory damage and iron skin deformation. For this reason, it is necessary to periodically clean the expansion allowance from the furnace.

  On the other hand, there is a structure in which the upper and lower portions are overlapped as shown in FIG. 5 in order to avoid the expansion allowance portion from reaching the inside of the furnace, but in this structure, the expansion absorption in the horizontal direction cannot be performed only by the expansion absorption in the height direction. .

  Further, Patent Document 1 discloses a structure in which upper and lower furnace walls are joined with a step, but this structure cannot absorb expansion in the horizontal direction only by absorbing expansion in the height direction.

JP 2002-162169 A

  The problem to be solved by the present invention is to provide a thermal expansion absorption structure for a furnace wall that does not allow expansion allowance to the inside of the furnace and can absorb not only the height direction but also the horizontal thermal expansion. .

Thermal expansion absorbing structure of the furnace wall present invention, the thermal expansion absorbing portion of the furnace wall in a cylindrical furnace, the lower surface is supported by a horizontal plane formed by the lower furnace wall, the back was contact with the inner surface of the upper furnace wall portion A refractory block that is made to slide is arranged in the circumferential direction, an expansion allowance in the height direction filled with refractory wool is provided on the back of the refractory block, and the iron skin side is gas-sealed with a heat-resistant cloth.

  Thus, in the present invention, in order to prevent the thermal expansion absorption part provided between the upper furnace wall and the lower furnace wall from communicating with the furnace, the fire expansion block is arranged in the circumferential direction in the thermal expansion absorption part, The lower surface of this refractory block is supported by a horizontal plane formed by the lower furnace wall, and the rear surface is in contact with the inner surface of the upper furnace wall, so that the thermal expansion in the height direction is the expansion allowance provided on the rear surface of the refractory block. Absorb in part. That is, since the rear surface of the refractory block is in contact with the inner surface of the upper furnace wall, the thermal expansion in the height direction can be absorbed by sliding of the contacted portion. Moreover, since this expansion | swelling allowance part exists in the back surface of a refractory block and is not open | released in the furnace, it can prevent a dust intrusion. On the other hand, thermal expansion in the horizontal direction can be absorbed by sliding with the lower furnace wall supporting the lower surface of the refractory block.

  In the thermal expansion absorption structure of the present invention, since the thermal expansion absorption part (expansion allowance part) does not lead to the inside of the furnace, it is possible to prevent a decrease in the expansion absorption capacity due to dust intrusion, and damage to the refractory and iron skin due to the expansion reaction force Can be prevented.

  Further, the thermal expansion absorption structure of the present invention can absorb not only the height direction but also the horizontal thermal expansion while exhibiting the above effects.

It is a longitudinal cross-sectional view which shows the thermal expansion absorption structure of this invention. It is CC sectional drawing of FIG. It is a longitudinal cross-sectional view which shows the state thermally expanded from the initial state of FIG. It is a longitudinal cross-sectional view which shows the conventional thermal expansion absorption structure. It is a longitudinal cross-sectional view which shows the conventional thermal expansion absorption structure. It is a longitudinal cross-sectional view which shows the structure of a cylindrical furnace.

  Hereinafter, embodiments of the present invention will be described based on examples shown in the drawings.

  1 is a longitudinal sectional view showing a thermal expansion absorption structure of the present invention, and FIG. 2 is a sectional view taken along the line CC in FIG.

  A refractory block 4a is arranged in the thermal expansion absorption part 4 between the upper furnace wall 1a and the lower furnace wall 1b. As shown in FIG. 2, the refractory blocks 4a are radially divided at equal intervals and placed on the plane X formed by the lower furnace wall 1b in the circumferential direction. Further, the back surface of the refractory block 4a is in contact with the inner surface Z of the upper furnace wall 1a. Further, the back surface of the fireproof block 4a is filled with fireproof wool 4b to form an expansion allowance A in the height direction. For expansion in the height direction, the expansion allowance A portion is compressed.

  In the embodiment, the upper part on the back side of the refractory block 4a is cut out and brought into contact with the inner surface Z of the upper furnace wall 1a. However, this is because of the lower surface of the refractory block 4a placed on the plane X. This is to increase the area and improve the stability of the fireproof block 4a.

  The refractory block 4a cannot move by itself with the adjacent block to the inside of the furnace, and the back surface is stopped by the inner surface Z of the upper furnace wall 1a. Therefore, the refractory block 4a moves integrally with the upper furnace wall 1a in the horizontal direction. The relative movement of the upper and lower furnace walls is made possible by sliding the refractory block 4a moving in conjunction with the upper furnace wall 1a on the plane X.

  FIG. 3 shows a state of thermal expansion from the initial state of FIG. In the height direction, A in FIG. 1 is compressed to A ′, and in the horizontal direction, the refractory block 4a slides on the plane X and moves B ′. Thus, the refractory block 4a slides on the inner surface Z of the upper furnace wall 1a for the thermal expansion in the height direction, and the refractory block 4a slides on the plane X for the thermal expansion in the horizontal direction. The expansion allowance C portion on the back of the refractory block 4a is isolated from the furnace dust environment. Further, the upper and lower iron skins 3 are connected by a heat-resistant cloth 4c on the outer side of the iron skin, and are gas-sealed without resisting relative movement of the upper and lower iron skins 3. Since the heat-resistant cloth 4c is thermally insulated by the fireproof wool 4b, it is thermally protected from the high temperature atmosphere in the furnace.

  In the embodiment, the fireproof block 4a is radially divided in the circumferential direction. However, the fireproof block 4a may be a ring-shaped integrated body without being divided. However, since it is difficult to manufacture the integrated object and it may be damaged by thermal shock or the like, it is preferable to divide it radially in the circumferential direction as in the embodiment.

  The cross-sectional shape of the cylindrical furnace to which the present invention is applied is typically circular, but the present invention is applicable even if it is elliptical.

  The present invention can be used for a cylindrical furnace (including its flue pipe and communication pipe) lined with a refractory that requires thermal expansion absorption. For example, it is particularly effective for a waste combustion furnace containing a large amount of dust in a high-temperature gas.

DESCRIPTION OF SYMBOLS 1 Cylindrical furnace 1a Upper furnace wall 1b Lower furnace wall 2 Furnace wall refractory 3 Iron skin 4 Thermal expansion absorption part 4a Fireproof block 4b Heat-resistant wool 4c Heat-resistant cloth 5 Connecting pipe A Height expansion allowance A 'After height direction movement Dimension B Horizontal expansion allowance B 'Horizontal movement dimension X Plane formed by lower furnace wall 1b (horizontal sliding surface)
Z inner surface of upper furnace wall 1a (height sliding surface)

Claims (2)

The thermal expansion absorbing portion of the furnace wall in a cylindrical furnace, the lower surface is supported by a horizontal plane formed by the lower furnace walls, rear refractory blocks have inner surfaces with contact portions of the upper furnace walls so as to slide in the circumferential direction The thermal expansion absorption structure of the furnace wall is arranged and provided with an expansion allowance in the height direction filled with refractory wool on the back of the refractory block, and the iron skin side is gas-sealed with a heat-resistant cloth.   The said refractory block is a thermal expansion absorption structure of the furnace wall of Claim 1 divided | segmented radially by the circumferential direction.

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