A furnace bottom structure for a rectangular furnace

Abstract

The application relates to a rectangular furnace bottom structure in the technical field of pyrometallurgical furnace equipment, and in particular to a rectangular furnace bottom structure. The rectangular furnace bottom structure comprises, from bottom to top, a heat preservation layer, a ramming layer, a safety layer and a working layer in sequence. The lower half of the heat preservation layer is filled horizontally, the upper half of the heat preservation layer is a structure symmetrically retreating to both sides, forming an arc-shaped surface, an arc-shaped ramming layer with a high middle and a low both ends is filled above the heat preservation layer, the safety layer and the working layer are sequentially built on the ramming layer, the upper surface of the working layer is arc-shaped with a high middle and a low both ends, a molten metal copper jacket is arranged on the adjacent furnace wall of the safety layer and the working layer, and a molten metal outlet is arranged in the molten metal copper jacket. The straight surface of the furnace bottom structure is changed into an arc surface, the structural strength and stability are high, the heat preservation layer and the working layer are closely contacted, the molten body leakage is prevented, the brick body expansion can be absorbed, the construction is convenient, the cost is low, and the rectangular furnace bottom structure is suitable for furnaces of different sizes.

Description

Technical Field

[0001] This utility model relates to the technical field of pyrometallurgical furnace equipment, specifically to a furnace bottom structure for a rectangular furnace. Background Technology

[0002] In the field of heavy metal smelting, the furnace bottom structure of rectangular furnaces (including blast furnaces, reverberatory furnaces, electric furnaces, flash furnaces, side-blown furnaces, and multi-lance top-blown furnaces) is a structural component that affects the operational safety and service life of the furnace. Traditional technologies commonly employ a flat furnace bottom structure with refractory bricks laid flat. However, this structure has revealed certain defects during long-term high-temperature smelting operations: due to the difference in the linear expansion coefficients of the refractory materials at high temperatures, the flat-laid refractory bricks undergo irreversible upward arching deformation under thermal stress. This structural deformation not only causes the overall furnace bottom to rise but also leads to compression cracking between adjacent refractory bricks, forming through-cracks. Especially when handling molten metal or highly corrosive melts, leaked liquid substances can erode the furnace bottom foundation layer along the cracks, and in severe cases, even penetrate the furnace bottom, causing production accidents. Although existing technologies attempt to alleviate expansion stress by thickening the refractory layer or adding compensating joints, the stress concentration characteristics of planar structures still cannot effectively solve the dual hidden dangers of refractory brick misalignment and cracking and melt penetration, resulting in a shortened furnace operation cycle and increased maintenance costs.

[0003] Therefore, it is necessary to design a safe and stable furnace bottom structure to improve the strength of the furnace bottom structure. Utility Model Content

[0004] To address the problems of existing technologies, this utility model proposes a furnace bottom structure for a rectangular furnace, the specific solution of which is as follows:

[0005] A rectangular furnace bottom structure includes: an insulation layer, a rammed layer, a safety layer, and a working layer. The insulation layer is built on top of the furnace bottom, with its lower half horizontally filled and its upper half symmetrically stepped back to both sides, the thickness of which still exceeds the wall thickness at the thickest point of the sidewall. A rammed layer is placed above the insulation layer, its upper surface being an arc shape with higher ends and a lower middle. A safety layer and a working layer are sequentially built on the rammed layer, the upper surface of which is also an arc shape with higher ends and a lower middle. The bricks used in each of the insulation, safety, and working layers are of equal size. A copper water jacket for molten metal is installed on the furnace wall adjacent to the safety and working layers. The lowest point of the upper surface of the working layer is horizontally lower than the molten metal outlet, and the highest point is horizontally higher than the molten metal outlet. A channel for molten metal passes through the copper water jacket and the working layer, connecting the interior and exterior of the furnace, with the port connecting to the exterior serving as the molten metal outlet.

[0006] Furthermore, the bricks used in the insulation layer, safety layer, and working layer are refractory bricks.

[0007] Furthermore, the material of the ramming layer is refractory ramming mix.

[0008] Furthermore, the bricks used in each layer are of different specifications: the brick height of the working layer is greater than that of the safety layer, and the brick height of the safety layer is greater than that of the insulation layer.

[0009] Furthermore, the highest point of the working layer is lower than the slag outlet, and the slag outlet is surrounded by a slag copper water jacket.

[0010] A method for constructing the above-mentioned furnace bottom structure includes the following steps:

[0011] Step 1: Build an insulation layer at the bottom of the furnace. The lower half of the insulation layer is a multi-layered filled structure, and the upper half is a stepped structure on both sides. The upper surface of the insulation layer is close to an arc shape.

[0012] Step 2: Draw the arc-shaped control line on the upper surface of the ramming layer on the longitudinal end face of the rectangular furnace;

[0013] Step 3: After mixing the ramming material evenly, lay it on the insulation layer, and use an arc-shaped template to scrape out the approximate arc along the arc control line;

[0014] Step 4: Use a vibratory tamper to compact the ramming material, then use an arc template to refine the arc surface that matches the arc control line, and use the ramming material to repair any local depressions.

[0015] Step 5: Dry the rammed layer using a hot air blower or resistance wire;

[0016] Step 6: Construct the safety layer and working layer sequentially along the arc surface of the rammed layer to create a furnace bottom structure with an inwardly concave arc surface.

[0017] This invention features an inverted arched furnace bottom structure, which helps prevent damage to the refractory masonry caused by the upward expansion of the furnace bottom bricks at high temperatures. A rammed layer is placed between the insulation layer and the safety layer, transforming the straight surface into an arc surface, so that both the safety layer and the working layer become arc-shaped structures. The rammed layer, located between the insulation and safety layers, acts as a transition, ensuring tight contact between the various layers of the furnace bottom and preventing leakage. The safety layer and working layer are adjacent to the molten metal outlet channel and the copper water jacket for cooling. The copper water jacket cools the furnace wall bricks, thereby cooling the inverted arched safety and working layers, further protecting the furnace bottom structure from damage. This masonry structure boasts advantages such as high structural strength and stability, close contact with the insulation and working layers to prevent molten leakage, absorption of brick expansion, convenient construction, low cost, and applicability to furnaces of different sizes. This masonry structure provides strong support for heavy metal pyrometallurgical production, effectively improves the service life of the furnace bottom of rectangular furnaces, thereby improving the overall service life of the rectangular furnace lining and ultimately increasing the operating rate of the rectangular furnace. Attached Figure Description

[0018] The embodiments of this utility model will be further described below with reference to the accompanying drawings, wherein:

[0019] Figure 1 A cross-sectional view of a rectangular furnace in an embodiment of the present invention is shown. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the scope of the present utility model.

[0021] In one embodiment, the bottom structure of a rectangular kiln includes: an insulation layer 1, a rammed layer 2, a safety layer 3, and a working layer 4. The insulation layer 1 is built on top of the bottom of the kiln. The lower half of the insulation layer 1 is horizontally filled. The upper half of the insulation layer 1 has a symmetrical stepped structure that slopes back to both sides, and the thickness of the stepped structure still exceeds the wall thickness at the thickest point of the side wall. The upper and lower halves are not strictly half, but are divided into two parts: an upper part and a lower part. The specific ratio can be determined according to the actual situation. The stepped structure means that the upper layer has fewer bricks than the lower layer near the middle, and bricks are only symmetrically built at both ends, with the empty part in the middle becoming larger as it goes up. The rammed layer 2 is filled on top of the insulation layer 1. The upper surface of the rammed layer 2 is an arc shape that is high at both ends and low in the middle. The safety layer 3 and the working layer 4 are built on the rammed layer 2 in sequence. The upper surface of the working layer 4 is an arc shape that is high at both ends and low in the middle. The bricks used in each layer of the insulation layer 1, safety layer 3, and working layer 4 are of equal size. A copper water jacket 5 for molten metal is installed on the adjacent furnace wall of safety layer 3 and working layer 4. The lowest point of the upper surface of working layer 4 is lower than the molten metal outlet 7 in the horizontal direction, and the highest point is higher than the molten metal outlet 7 in the horizontal direction. The molten metal channel passes through the copper water jacket 5 and working layer 4 in sequence, connecting the inside and outside of the furnace. The port connecting to the outside is the molten metal outlet 7. The highest point of working layer 4 is lower than the slag outlet 8, and the slag outlet 8 is surrounded by the slag copper water jacket 6. The bricks of insulation layer 1, safety layer 3, and working layer 4 are refractory bricks. The material of rammed layer 2 is refractory ramming material, specifically magnesium oxide refractory ramming material. The brick specifications used in each layer are different: the brick height of working layer 1 is greater than that of safety layer 3, and the brick height of safety layer 3 is greater than that of insulation layer 4.

[0022] The method for constructing the furnace bottom structure of a rectangular furnace includes the following steps:

[0023] Step 1: Build an insulation layer at the bottom of the furnace. The lower half of the insulation layer is a multi-layered filled structure, and the upper half is a stepped structure on both sides. The upper surface of the insulation layer is close to an arc shape.

[0024] Step 2: Draw the arc-shaped control line on the upper surface of the ramming layer on the longitudinal end face of the rectangular furnace;

[0025] Step 3: After mixing the ramming material evenly, lay it on the insulation layer, and use an arc-shaped template to scrape out the approximate arc along the arc control line;

[0026] Step 4: Use a vibratory tamper to compact the ramming material, then use an arc template to refine the arc surface that matches the arc control line, and use the ramming material to repair any local depressions.

[0027] Step 5: Dry the rammed layer using a hot air blower or resistance wire;

[0028] Step 6: Construct the safety layer and working layer sequentially along the arc surface of the rammed layer to create a furnace bottom structure with an inwardly concave arc surface.

[0029] The foregoing description describes some exemplary embodiments of this utility model. It is understood that the above embodiments are only used to explain this utility model and do not constitute a limitation on the scope of protection of this utility model. The features in these embodiments can be recombine in a suitable manner, and the resulting solutions are still within the scope of protection claimed by this utility model. Based on the above embodiments, all other embodiments obtained by those skilled in the art without inventive effort, that is, all modifications, equivalent substitutions, and improvements made within the spirit and principles of this application, fall within the scope of protection claimed by this utility model.

Claims

1. A furnace bottom structure for a rectangular kiln, characterized in that, include: The furnace consists of an insulation layer (1), a rammed layer (2), a safety layer (3), and a working layer (4). The insulation layer (1) is built above the furnace bottom. The lower half of the insulation layer (1) is horizontally filled. The upper half of the insulation layer (1) has a symmetrical stepped structure that extends to both sides, and the thickness of the stepped structure still exceeds the wall thickness at the thickest point of the side wall. The insulation layer (1) is filled with a rammed layer (2) above it. The upper surface of the rammed layer (2) is an arc shape with high ends and low middle. The safety layer (3) and the working layer (4) are built on the rammed layer (2) in sequence. The upper surface of the working layer (4) is an arc shape with high ends and low middle. The arc shape is high at both ends and low in the middle; the bricks used in the insulation layer (1), safety layer (3) and working layer (4) are of equal size; a copper water jacket (5) for molten metal is provided on the adjacent furnace wall of the safety layer (3) and working layer (4); the lowest point of the upper surface of the working layer (4) is lower than the molten metal outlet (7) in the horizontal direction, and the highest point is higher than the molten metal outlet (7) in the horizontal direction; the channel of molten metal passes through the copper water jacket (5) and working layer (4) in sequence to connect the inside and outside of the furnace, and the port connecting to the outside is the molten metal outlet (7).

2. The furnace bottom structure of a rectangular furnace according to claim 1, characterized in that, The bricks of the insulation layer (1), safety layer (3) and working layer (4) are refractory bricks.

3. The furnace bottom structure of a rectangular furnace according to claim 1, characterized in that, The material of the ramming layer (2) is refractory ramming material.

4. The furnace bottom structure of a rectangular furnace according to claim 1, characterized in that, The bricks used in each layer are of different specifications: the brick height of the working layer (4) is greater than that of the safety layer (3), and the brick height of the safety layer (3) is greater than that of the insulation layer (1).

5. The furnace bottom structure of a rectangular furnace according to claim 1, characterized in that, The highest point of the working layer (4) is lower than the slag outlet (8), which is surrounded by the slag copper water jacket (6).

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