Metal smelting furnace

Abstract

A metal smelting furnace comprises a furnace body, the furnace body is provided with a crucible and a combustion chamber used for heating the crucible, the furnace body is further provided with a heat exchange device, a containing cavity is formed in the heat exchange device, an exhaust port of the combustion chamber is communicated with the containing cavity, and the exhaust direction of the containing cavity faces an opening of the crucible. Multiple cyclic utilization of discharged flue gas is achieved, the flue gas heat recovery efficiency is improved, and the use cost is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of metal melting furnaces, in particular to a metal melting furnace. Background Art

[0002] At present, metal melting furnaces on the market can be divided into electric furnaces and flame furnaces according to different heating energy sources. Those using electricity as the energy source are collectively called electric furnaces, and electric furnaces can be further divided into resistance reverberatory furnaces and induction furnaces. Using an electric furnace has the advantages of small burning loss, small pollution, and good working environment. However, its disadvantages such as high equipment investment, large power consumption, and slow heating rate make it not suitable for large-scale melting. Furnaces that use diesel, coal, liquefied gas, natural gas, etc. as fuel for combustion heating are collectively called flame furnaces. Flame furnaces have the advantages of fast melting speed, high output, and low cost. Therefore, flame furnaces occupy a dominant position in the melting furnace market in China.

[0003] However, at present, the smoke exhaust method of flame furnaces on the market is mainly direct smoke exhaust, and there are certain problems with this smoke exhaust method. During the melting stage of the metal, the temperature in the furnace is usually controlled at 1100°C - 1200°C. At this time, the temperature of the exhausted flue gas is the heating temperature in the furnace, and the heat carried away by the flue gas accounts for about 60% of the furnace heat load. If this part of the waste heat is not fully utilized, it will cause a certain amount of heat energy loss. Summary of the Utility Model

[0004] Aiming at the deficiencies in the background art, the purpose of the utility model is to provide a metal melting furnace.

[0005] To achieve the above purpose, the utility model provides the following technical solutions:

[0006] A metal melting furnace, including a furnace body, the furnace body is provided with a crucible and a combustion chamber for heating the crucible, the furnace body is further equipped with a heat exchange device, the heat exchange device is provided with a placement cavity, the exhaust port of the combustion chamber is communicated with the placement cavity, and the exhaust direction of the placement cavity faces the opening of the crucible.

[0007] Further, it also includes a first connecting pipe, and the exhaust port of the combustion chamber is communicated with the placement cavity through the first connecting pipe.

[0008] Further, the heat exchange device is provided with at least one door body for opening and closing the placement cavity.

[0009] Further, the heat exchange device is provided with a driving device for automatically opening and closing the door body.

[0010] Further, it also includes an exhaust pipe, one end of the exhaust pipe is communicated with the placement cavity, and the other end of the exhaust pipe faces the opening of the crucible.

[0011] Further, pulleys for facilitating the movement of the furnace body are installed at the bottom of the furnace body.

[0012] Furthermore, the furnace body is provided with an installation groove for installing the crucible, and the furnace body is also provided with a liquid leakage port communicating with the installation groove, and the liquid leakage port is used for discharging the molten metal leaked due to the breakage of the crucible.

[0013] Furthermore, a heat insulation and anti-scalding layer is provided on the inner wall or outer wall of the combustion chamber and the heat exchange device.

[0014] The beneficial effects of the present utility model are as follows:

[0015] 1. A metal melting furnace proposed by the present utility model includes a furnace body. The furnace body is provided with a crucible and a combustion chamber for heating the crucible. The furnace body is also equipped with a heat exchange device. A placement cavity is provided in the heat exchange device. The exhaust port of the combustion chamber communicates with the placement cavity, and the exhaust direction of the placement cavity faces the opening of the crucible. This metal melting furnace is highly efficient and energy-saving, realizing multiple recycling of the discharged flue gas, improving the heat recovery efficiency of the flue gas, and reducing the use cost.

[0016] 2. A metal melting furnace proposed by the present utility model has pulleys installed at the bottom of the furnace body, facilitating the movement of the entire melting furnace; the furnace body is provided with an installation groove for installing the crucible, and the furnace body is also provided with a liquid leakage port communicating with the installation groove, and the liquid leakage port is used for discharging the molten metal leaked due to the breakage of the crucible.

[0017] 3. A metal melting furnace proposed by the present utility model has a heat insulation and anti-scalding layer provided on the inner wall or outer wall of the combustion chamber and the heat exchange device, providing good heat insulation, reducing energy loss, and also avoiding scalding caused by accidental human contact. Description of the Drawings

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the utility model or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the utility model. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0019] Figure 1 It is a schematic diagram of a metal melting furnace of the present utility model;

[0020] Figure 2 It is the front view of a metal melting furnace of the present utility model;

[0021] Figure 3 It is the left view of a metal melting furnace of the present utility model;

[0022] Figure 4 It is a schematic diagram of the furnace body;

[0023] Figure 5 It is a schematic diagram of the heat exchange device;

[0024] In the figure, 10 is the furnace body; 101 is the crucible; 102 is the combustion chamber; 20 is the air suction device; 30 is the heat exchange device; 301 is the placement cavity; 302 is the heat exchange part; 303 is the door body; 304 is the driving device; 401 is the first connecting pipe; 402 is the exhaust pipe; 501 is the pulley; 502 is the installation groove; 503 is the liquid leakage port; 504 is the placement table; 60 is the heat preservation and anti-scalding layer. Specific embodiments

[0025] The following is combined with Figures 1-5 to describe the present utility model in detail.

[0026] A metal melting furnace includes a furnace body 10. The furnace body 10 is provided with a crucible 101 and a combustion chamber 102 located below the crucible 101. The furnace body 10 is further installed with a heat exchange device 30. A placement cavity 301 is provided inside the heat exchange device 30. The exhaust port of the combustion chamber 102 is communicated with the placement cavity 301, and the exhaust direction of the placement cavity 301 faces the opening of the crucible 101. This metal melting furnace is highly efficient and energy-saving, realizing multiple recycling of the discharged flue gas, improving the heat recovery efficiency of the flue gas, and reducing the use cost.

[0027] Specifically, the furnace body 10 is made of carbon steel plate; the crucible 101 is a component for loading the metal to be melted. The crucible 101 is made of refractory material, which can resist high temperature, prevent the metal from reacting chemically with the furnace wall, and during the melting process, can help the metal separate its impurities, making the melted metal purer; when natural gas is used as fuel in the combustion chamber 102, the fuel cost is lower than the costs of electricity, liquefied gas and diesel; the heat exchange device 30 is installed on the outer side wall of the furnace body 10.

[0028] Furthermore, the furnace body 10 is further installed with an air suction device 20. The air suction port of the air suction device 20 is communicated with the external atmospheric environment. A heat exchange part 302 is provided inside the placement cavity 301. The exhaust port of the combustion chamber 102 and the air outlet of the air suction device 20 are respectively communicated with the placement cavity 301. A positive and negative rotation fan is provided inside the combustion chamber 102 or at the connection between the exhaust port of the combustion chamber 102 and the placement cavity 301, and the positive and negative rotation fan faces the exhaust direction of the combustion chamber 102. The air suction device 20 is used to suck in the external cold air to make it exchange heat with the heat exchange part 302, and the hot air after heat exchange is sucked back into the combustion chamber 102 by the positive and negative rotation fan to assist combustion, thereby realizing one more recycling of the discharged flue gas, further improving the heat recovery efficiency of the flue gas, and reducing the use cost.

[0029] The air intake device 20 is a high-pressure blower. A high-pressure blower is a mechanical device that, through physical principles, uses power to suck in gas and then compresses and transports the gas through processes such as compression to achieve the purpose of pressurization. It is mainly used in important industrial fields such as combustion, heat exchange, papermaking, and smelting. In the combustion field, the high-pressure blower can provide the air required for combustion, control the oxygen content, and at the same time provide the required pressure through the pressurization effect to ensure the stability and reliability of the combustion process. In the heat exchange field, the high-pressure blower can be used as an air supply blower to send the required air into the heat exchange device 30, control the air pressure, and promote the good operation of the heat exchange device 30.

[0030] The heat exchange part 302 is a number of finned tubes. Specifically, 20 finned tubes are provided at the top inside the placement cavity 301. The finned tubes are of the prior art and will not be elaborated here.

[0031] The forward and reverse blower can rotate forward or reverse according to needs. As Figure 2 shown, when in the first stage and the hot gas in the combustion chamber 102 needs to flow into the placement cavity 301 through the first connecting pipe 401, the forward and reverse blower starts to rotate forward, thereby generating a wind force to the right, generating a wind adsorption at the left side of the exhaust port of the combustion chamber 102, so as to assist the hot gas in the combustion chamber 102 to flow into the placement cavity 301 through the first connecting pipe 401; when in the second stage and the air after heat exchange in the placement cavity 301 needs to return to the combustion chamber 102 through the first connecting pipe 401 to be mixed with the fuel, the forward and reverse blower is started at this time, so that the forward and reverse blower rotates in reverse, generating a wind adsorption at the right side of the exhaust port of the combustion chamber 102, and then sucking the air after heat exchange in the placement cavity 301 back into the combustion chamber 102. The forward and reverse blower uses a high-temperature resistant forward and reverse blower.

[0032] In this embodiment, it further includes a first connecting pipe 401 and a second connecting pipe. The exhaust port of the combustion chamber 102 is connected to the placement cavity 301 through the first connecting pipe 401, and the air outlet of the high-pressure blower is connected to the placement cavity 301 through the second connecting pipe. As Figure 2 shown, the second connecting pipe is located behind the first connecting pipe 401.

[0033] In this embodiment, the heat exchange device 30 is provided with at least one door body 303 that can open and close the placement cavity 301. Further, the heat exchange device 30 is provided with a driving device 304 for automatically opening and closing the door body 303. Specifically, the driving device 304 is a cylinder provided on the outer wall of the heat exchange device 30, and the automatic opening and closing of the door body 303 is realized by controlling the cylinder through a button; the driving device 304 can also be other devices of the prior art as long as it can perform the function of automatically opening and closing the door body 303.

[0034] In this embodiment, an exhaust pipe 402 is further included. One end of the exhaust pipe 402 communicates with the placement cavity 301, and the other end of the exhaust pipe 402 opens towards the crucible 101. A cover body (not shown in the figure) may be provided at the opening of the crucible 101. The cover body is provided with a discharge hole. The other end of the exhaust pipe 402 communicates with the inside of the cover body. The setting of the cover body enables the hot air of the exhaust pipe 402 to heat the metal in the crucible 101 to a greater extent.

[0035] In this embodiment, pulleys 501 for facilitating the movement of the furnace body 10 are installed at the bottom of the furnace body 10. Since the suction device 20 and the heat exchange device 30 are installed on the outer side wall of the furnace body 10, moving the furnace body 10 means moving the entire metal melting furnace; further, the furnace body 10 is provided with an installation groove 502 for installing the crucible 101, and the furnace body 10 is further provided with a liquid leakage port 503 communicating with the notch of the installation groove 502. The liquid leakage port 503 is used to discharge the metal liquid leaked due to the breakage of the crucible 101; further, the furnace body 10 is provided with a placement table 504, which can be used to temporarily place the metal just taken out of the placement cavity 301 or place other items; the combustion chamber 102 is further provided with a temperature control device, and the temperature control device specifically refers to the prior art.

[0036] In this embodiment, a heat preservation and anti-scalding layer 60 is provided on the inner wall or outer wall of the combustion chamber 102 and the heat exchange device 30. While the heat preservation and anti-scalding layer 60 provides good heat preservation and reduces energy loss, it can also prevent scalding caused by accidental contact by the human body; specifically, the heat preservation and anti-scalding layer 60 of the combustion chamber 102 is made of refractory bricks or refractory cotton, and the heat preservation and anti-scalding layer 60 of the heat exchange device 30 is made of aluminosilicate heat preservation cotton with a thickness of 90 mm.

[0037] The working principle of a metal melting furnace proposed by the present utility model is as follows:

[0038] The first step: Natural gas burns in the combustion chamber 102. At the beginning, the metal to be melted is not put into the crucible 101 first. Instead, the door body 303 of the heat exchange device 30 is opened and put into the placement cavity 301. When the high-temperature flue gas flows in the combustion chamber 102, it transfers heat to the bottom of the crucible 101 located above the combustion chamber 102 while the flue gas flows into the placement cavity 301 through the first connecting pipe 401. At this time, the flue gas preheats the metal in the placement cavity 301; when the liquid level in the crucible 101 drops, it means that the crucible 101 is preheated, and then the heated metal is put into the crucible 101.

[0039] The second stage: In the first stage, the flue gas also heats the finned tubes in the placement cavity 301. Therefore, the finned tubes are hot in the second stage. The high-pressure blower draws in cold air from the outside and transports it into the placement cavity 301 through the second connecting pipe. The air converges from one side of the finned tubes to the other side. After two returns, the air exchanges heat with the finned tubes and is heated. Then, the heated air returns to the combustion chamber 102 through the first connecting pipe 401 under the action of the forward and reverse blower and mixes with the fuel, which not only increases the flame temperature but also has an energy-saving effect.

[0040] The third stage: The flue gas is discharged through the exhaust pipe 402, and during the discharge, it further heats the metal in the crucible 101.

[0041] In the first stage, the flue gas flows into the placement cavity 301 through the first connecting pipe 401, is then discharged through the exhaust pipe 402, and also preheats the crucible 101. A switching valve can also be set in the exhaust pipe 402 so that the flue gas in the first stage does not discharge after flowing into the placement cavity 301 through the first connecting pipe 401, but only flows between the combustion chamber 102 and the placement cavity 301 and within them. This can better heat the metal and finned tubes in the placement cavity 301. In the second stage, the power of the forward and reverse blower needs to be adjusted so that it does not suck the cold air outside the exhaust pipe 402 into the combustion chamber 102 due to excessive power, or the switching valve in the exhaust pipe 402 is closed when the forward and reverse blower rotates in reverse.

[0042] The above embodiments are only used to illustrate the technical concept and features of the present invention. Their purpose is to enable those skilled in the art to understand the content of the present invention and implement it, but it cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit and essence of the present invention should be covered within the protection scope of the present invention.

Claims

1. A metal smelting furnace, characterized in that: The invention comprises a furnace body, wherein the furnace body is provided with a crucible and a combustion chamber for heating the crucible. The furnace body is also equipped with a heat exchange device, wherein a placement cavity is provided in the heat exchange device, an exhaust port of the combustion chamber is connected to the placement cavity, and an exhaust direction of the placement cavity is toward the crucible opening.

2. A metal smelting furnace as claimed in claim 1, characterized in that: It also includes a first connecting pipe, through which the exhaust port of the combustion chamber is connected to the placement cavity.

3. A metal smelting furnace as claimed in claim 1, characterized in that: The heat exchange device is provided with at least one door body capable of opening and closing the placement cavity.

4. A metal smelting furnace as claimed in claim 3, characterized in that: The heat exchange device is provided with a driving device for driving the door body to automatically open and close.

5. A metal smelting furnace as claimed in claim 1, characterized in that: It also includes an exhaust pipe, one end of which is connected to the placement cavity, and the other end of which opens toward the crucible.

6. A metal smelting furnace as claimed in claim 1, characterized in that: The bottom of the furnace body is provided with a pulley for facilitating the movement of the furnace body.

7. A metal smelting furnace as claimed in claim 1, characterized in that: The furnace body is provided with a mounting groove for mounting the crucible, and the furnace body is also provided with a liquid leakage port connected with the mounting groove, and the liquid leakage port is used to discharge the metal liquid leaked due to the breakage of the crucible.

8. A metal smelting furnace as claimed in claim 1, characterized in that: The inner wall or outer wall of the combustion chamber and the heat exchange device is provided with a heat-insulating and scalding-proof layer.

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