Heat preservation stock bin for submerged arc furnace

Abstract

The utility model relates to a heat preservation stock bin for a submerged arc furnace in the field of iron alloy smelting equipment. The storage bin is mainly composed of a metal wall plate (1), a reinforcing piece (2), an outlet connecting pipe (3), slag hanging nails (4), a nanometer high-temperature heat insulation plate (5) and a fire-resistant knotting material (6). A stock bin shell is formed by welding a plurality of metal wall plates (1), reinforcing pieces (2) are welded to the outer surfaces of the metal wall plates (1), a plurality of outlet connecting pipes (3) are further welded to the metal wall plates (1) at the bottom of the stock bin, and a plurality of slag hanging nails (4) are welded to the inner surfaces of the metal wall plates (1). The nanometer high-temperature heat insulation plate (5) is pasted on the inner surface of the metal wall plate (1), and the fireproof knotting material (6) covers the nanometer high-temperature heat insulation plate (5) and the slag hanging nails (4). According to the technical scheme, the problems that an existing stock bin is high in manufacturing and maintaining cost and large in heat loss are solved, the effect of reducing smelting energy consumption is obvious, and positive significance is achieved for energy conservation and efficiency improvement of smelting enterprises.

Description

Technical Field

[0001] The utility model relates to the field of ferroalloy smelting equipment, in particular to a heat-insulating silo for a submerged arc furnace. Background Art

[0002] Submerged arc furnace is an important equipment for producing ferroalloys. It is mainly composed of furnace body, electrode holding system, hydraulic system, charging system, cooling system, iron tapping system, slag tapping system, flue gas collection and dust removal system, etc. The silo is installed on the top of the furnace and is an important component in the charging system. In the ferroalloy production process, the high-temperature materials that have been preheated or (and) pre-reduced are first added to the silo, and then added to the furnace at a fixed time and quantity according to the process requirements. Therefore, the insulation effect of the silo has a direct impact on the energy consumption of the smelting process. Reasonable material selection and insulation structure can effectively reduce heat loss, reduce energy consumption, improve production efficiency, and reduce manufacturing and maintenance costs. The existing silo of submerged arc furnace generally adopts a structure of high-temperature refractory materials knotted on the inner surface of the metal wall plate and insulation materials such as rock wool, glass fiber or aluminum silicate fiber felt added to the outer surface. Since heat-resistant stainless steel and other materials are used to make silo wall panels and other components, the manufacturing cost of the silo is high; the silo using the above-mentioned insulation materials reduces heat loss to a certain extent, but since these insulation materials have a large thermal conductivity at high temperatures, in order to achieve a better insulation purpose, the thickness of the insulation materials has to be greatly increased, which results in the silo's outer dimensions being larger and the overall weight being larger, which not only occupies more space on the top of the furnace, but also brings some other problems. In addition, some silos use heat-resistant stainless steel and other materials as wall panels and tie high-temperature refractory materials on the inner surface of the wall panels, which has more prominent problems in terms of heat loss and silo life, especially in the production of some ferroalloys. For example, in the RK-EF process for smelting nickel iron in laterite nickel ore, the temperature of the pre-reduced high-temperature hot roasted sand added to the silo from the rotary kiln is nearly 850°C. With the existing silo, the outer wall temperature is nearly 360°C, which causes a lot of heat loss, adversely affects the equipment around the silo, and reduces the service life of the silo wall panels, increasing maintenance costs. Summary of the invention

[0003] In order to solve the above problems, the utility model proposes an insulation silo for a submerged arc furnace, which adopts the relatively low-priced Q355B material to make the metal wall plate of the silo, welds a certain number of slag nails on the inner wall and sticks a certain thickness of nano high-temperature insulation board, and then covers the outside of the nano high-temperature insulation board and the slag nails with refractory knotting material.

[0004] The utility model adopts the following technical solution to solve the technical problem: a heat-insulating silo for an electric arc furnace mainly comprises a metal wall plate (1), a reinforcement member (2), an outlet pipe (3), a slag nail (4), a nanometer high-temperature insulation board (5) and a refractory knotting material (6); the silo shell is welded by a plurality of metal wall plates (1); a reinforcement member (2) is welded on the outer surface of the metal wall plate (1); a plurality of outlet pipes (3) are welded on the metal wall plate (1) at the bottom of the silo; and a plurality of slag nails (4) are welded on the inner surface of the metal wall plate (1); the nanometer high-temperature insulation board (5) is adhered to the inner surface of the metal wall plate (1); and the refractory knotting material (6) covers the outside of the nanometer high-temperature insulation board (5) and the slag nail (4).

[0005] Preferably, the metal wall plate (1), the reinforcement (2) and the outlet pipe (3) are all made of Q355B material, the welded joints between the metal wall plates (1) are all of the full penetration type, and a full penetration type welding structure is adopted between the metal wall plate (1) and the outlet pipe (3).

[0006] Preferably, the slag nail (4) is made of Q235B material, and the contact portion between the slag nail (4) and the metal wall plate (1) is welded in a double-sided continuous fillet weld type structure.

[0007] Preferably, the nano high temperature insulation board (5) has a thickness of 30 to 60 mm and is composed of one or more layers, and its operating temperature is not less than 900°C.

[0008] Preferably, the thickness of the refractory knotting material (6) is 150 to 200 mm, and its refractoriness is not less than 1600°C.

[0009] Preferably, the distance between adjacent slag nails (4) is 200 to 300 mm.

[0010] The beneficial effects of the utility model are: using the relatively low-priced Q355B material to make the silo wall panels, reinforcements and outlet pipes, and using the Q235B material to make the slag nails, which greatly reduces the manufacturing cost of the silo compared with using heat-resistant stainless steel and other materials; using the nano high-temperature insulation board with a very low high-temperature thermal conductivity as the insulation material, greatly reducing the outer wall temperature of the silo, and at the same time, reducing the silo's external dimensions and material consumption to a certain extent; using the slag nails to ensure that the refractory knotting material can be reliably covered on the outside of the nano high-temperature insulation board and the slag nails, protecting the nano high-temperature insulation board and other parts of the silo. The insulation silo of the utility model has a significant effect in reducing smelting energy consumption, greatly increases its service life, and significantly reduces maintenance costs, which has positive significance for energy saving and efficiency improvement of smelting enterprises. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The utility model is further described below in conjunction with the accompanying drawings and embodiments.

[0012] Figure 1 This is the front view (schematic diagram) of the thermal insulation silo of the utility model.

[0013] Figure 2 It is a side view (schematic diagram) of the thermal insulation silo of the utility model.

[0014] Figure 3 for Figure 2 Partial magnification Figure Ⅰ .

[0015] Figure 4 It is a side view of an existing silo (the inner surface of the silo wall panel is not pasted with nano high-temperature insulation board, and the outer surface is covered with aluminum silicate fiber felt; schematic diagram).

[0016] Figure 5 for Figure 4 Partial magnification Figure II .

[0017] Figure 6 It is a side view of the existing silo (the inner surface of the silo wall panel is not pasted with nano high-temperature insulation board, schematic diagram).

[0018] In the figure: 1. Metal wall panel, 2. Reinforcement member, 3. Outlet pipe, 4. Slag nail, 5. Nano high temperature insulation board, 6. Refractory knotting material, 7. Aluminum silicate fiber felt. DETAILED DESCRIPTION

[0019] Figure 1 , 23 show a preferred embodiment of the utility model. In this embodiment, the heat-insulating silo is mainly composed of a metal wall plate (1), a reinforcement (2), an outlet pipe (3), a slag nail (4), a nano-high-temperature insulation board (5) and a refractory knotting material (6). The silo shell is welded by several metal wall plates (1), and a reinforcement (2) is welded on the outer surface of the metal wall plate (1). A plurality of outlet pipes (3) are welded on the metal wall plate (1) at the bottom of the silo, and a plurality of slag nails (4) are welded on the inner surface of the metal wall plate (1). The nano-high-temperature insulation board (5) is attached to the inner surface of the metal wall plate (1), and the refractory knotting material (6) covers the outside of the nano-high-temperature insulation board (5) and the slag nail (4). The metal wall plate (1), the reinforcement (2) and the outlet pipe (3) are all made of Q355B material, which greatly reduces the manufacturing cost compared with using heat-resistant stainless steel and other materials. The welding joints between the metal wall plates (1) are all of full penetration type, and the metal wall plates (1) and the outlet pipe (3) adopt a full penetration type welding structure, which ensures the structural reliability of the silo. The slag nails (4) are made of Q235B material, which reduces the material cost; the contact part between them and the metal wall plates (1) adopts a double-sided continuous fillet weld type welding structure, which ensures that the connection with the silo wall plates is firm and reliable. The nano high temperature insulation board (5) has a thickness of 30 to 60 mm and is composed of one or more layers. Its use temperature is not less than 900°C; the nano high temperature insulation board (5) is used as a heat insulation material, which significantly reduces the temperature of the outer wall of the silo and also reduces the heat resistance requirements for the metal material of the silo wall plate. The refractory knotting material (6) has a thickness of 150 to 200 mm and a refractoriness of not less than 1600°C; the refractory knotting material (6) effectively protects the nano high temperature insulation board (5) and other parts of the silo, reducing the adverse effects of high temperature. The spacing between adjacent slag nails (4) is 200 to 300 mm, which is conducive to the refractory knotting material (6) being reliably coated on the outside of the nano high-temperature insulation board (5).

[0020] In practical applications, when the material temperature in the silo is 850℃, the outer wall temperature of the silo is about 90℃ when the 30mm thick nano high temperature insulation board is used; the outer wall temperature of the silo is about 62℃ when the 60mm thick nano high temperature insulation board is used. Such low temperature is of great significance to the long-term reliable operation of the silo, and significantly reduces the smelting energy consumption. For example, for an effective volume of about 44m 3 For a silo (effective size is about 2.5m×2.5m×7.2m high), using a 30mm thick nano high-temperature insulation board, the heat loss is about 51kW▪h per hour, and the heat loss is about 1224kW▪h per day; using a 60mm thick nano high-temperature insulation board, the heat loss is about 28kW▪h per hour, and the heat loss is about 672kW▪h per day.

[0021] Figure 4 and Figure 5The figure shows a side view (schematic diagram) of an existing silo. In this comparative example, the inner surface of the silo wall is not pasted with nano high temperature insulation board, and the outer surface is covered with aluminum silicate fiber felt (7) with a thickness of 150mm; when the temperature of the material in the silo is 850℃, the temperature of the outer wall of the silo is about 83℃. For an effective volume of about 44m 3 For a silo with an effective size of approximately 2.5m×2.5m×7.2m in height), the additional weight is approximately 3500kg, the metal material temperature of the silo wall is approximately 765℃, the heat loss is approximately 68kW▪h per hour, and the heat loss is approximately 1632kW▪h per day.

[0022] Figure 6 The figure shows a side view (schematic diagram) of another type of existing silo. In this comparative example, the inner surface of the silo wall is not pasted with nano high temperature insulation board (5), and the outer surface is not covered with aluminum silicate fiber felt (7) or other insulation materials. When the material temperature in the silo is 850℃, the metal material temperature of the silo wall is about 360℃. For an effective volume of about 44m 3 For a silo (effective size is about 2.5m×2.5m×7.2m high), the heat loss per hour is about 430kW▪h, and the heat loss per day is about 10320kW▪h. A 48MVA nickel-iron submerged arc furnace has 8 silos, and the heat loss per day is about 82560 kW▪h.

[0023] The above description is only a preferred embodiment of the utility model and is not intended to limit the utility model. Although the utility model is described in detail with reference to the above embodiments and comparative examples, those skilled in the art can still modify the technical solutions recorded in the above preferred embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

Claims

1. A heat preservation silo for a submerged arc furnace, comprising a metal wall plate (1), a reinforcement member (2), an outlet pipe (3), a slag nail (4), a nano high temperature insulation board (5) and a refractory knotting material (6); characterized in that: The outer shell of the silo is welded by several metal wall plates (1), a reinforcement piece (2) is welded on the outer surface of the metal wall plates (1), a plurality of outlet pipes (3) are welded on the metal wall plates (1) at the bottom of the silo, and several slag nails (4) are welded on the inner surface of the metal wall plates (1); a nano high-temperature insulation board (5) is pasted on the inner surface of the metal wall plates (1), and a refractory knotting material (6) covers the outside of the nano high-temperature insulation board (5) and the slag nails (4).

2. The insulation silo for a submerged arc furnace according to claim 1, characterized in that: The metal wall plate (1), the reinforcement (2) and the outlet pipe (3) are all made of Q355B material. The welded joints between the metal wall plates (1) are all of the full penetration type. The metal wall plate (1) and the outlet pipe (3) have a full penetration type welding structure.

3. The insulation silo for a submerged arc furnace according to claim 1, characterized in that: The slag nail (4) is made of Q235B material, and the contact portion between the slag nail and the metal wall plate (1) adopts a double-sided continuous fillet weld type welding structure.

4. The insulation silo for a submerged arc furnace according to claim 1, characterized in that: The nano high temperature insulation board (5) has a thickness of 30 to 60 mm and is composed of one or more layers. Its use temperature is not less than 900°C.

5. The insulation silo for a submerged arc furnace according to claim 1, characterized in that: The thickness of the refractory knotting material (6) is 150-200 mm, and its refractoriness is not less than 1600°C.

6. The insulation silo for a submerged arc furnace according to claim 3, characterized in that: The spacing between adjacent slag nails (4) is 200 to 300 mm.

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