Composite melting furnace

Abstract

The utility model relates to a combined type melting furnace, which comprises a melting furnace and a material inlet, and the material inlet is positioned on a furnace cover of the melting furnace. The device further comprises a fuel spray gun and a plasma generator which share an insertion opening, and the insertion opening is located in the melting furnace cover and adjacent to the material inlet. The uptake flue is located on the melting furnace cover, forms an included angle with the melting furnace cover and is adjacent to the material inlet or the insertion opening. The socket can be shared by a fuel spray gun and a plasma generator, a standby socket can be started under special conditions, and the fuel spray gun and the plasma generator can be used at the same time. The advantages of a combustion type melting furnace can be embodied, on the premise that valuable metal does not need to be refined, large-batch production is achieved, the advantages of a plasma melting furnace can be embodied, high-temperature melting is conducted, and valuable metal refining is achieved. The pressure transmitter and the lifting system form a control loop to adjust the depth of the fuel spray gun or the plasma generator inserted into the hearth.

Description

Technical Field

[0001] The utility model relates to the technical field of hazardous waste disposal, in particular to a composite melting furnace. Background Art

[0002] Solid wastes such as slag and hazardous wastes generated by the incineration of hazardous wastes, hazardous wastes generated by the incineration of domestic waste and municipal sludge, electroplating sludge and copper-containing sludge are hazardous wastes because they contain toxic pollutants such as heavy metals and dioxins. Their safe disposal is related to environmental safety. Improper disposal will cause secondary environmental pollution and pose potential risks to human health. Melt solidification technology uses heat to melt solid pollutants into glass or glass-ceramic substances at high temperatures, and ensures the permanent stability of the solidified body with the help of the dense crystalline structure of the glass. After the pollutants undergo vitrification, the organic pollutants will be destroyed by pyrolysis or converted into gas to escape, while the radioactive elements and heavy metal elements will be firmly bound in the solidified glass.

[0003] Patent application number: 202021574534.2, application date: August 3, 2020, utility model name: A multi-mode oxygen supply melting furnace system, including a melting furnace, a flue gas purification unit, an oxygen production unit, a mixer, a flue gas unit and an oxygen supply unit; the melting furnace is provided with a feed port, a plurality of oxygen supply lances, a slag discharge port, a liquid metal discharge port and a flue gas discharge port; the flue gas discharge port is connected to the flue gas purification unit through a flue gas discharge pipe; the oxygen production unit includes an oxygen generator and an oxygen production pipeline, one end of the oxygen production pipeline is connected to the oxygen generator, and the other end is connected to the mixer; the flue gas unit includes a bypass flue, one end of the bypass flue is connected to the flue gas purification unit, and the other end is connected to the mixer; the oxygen supply unit includes an oxygen supply pipeline, one end of the oxygen supply pipeline is connected to the mixer, and the other end is connected to a plurality of oxygen supply lances. It has the advantages of low energy consumption and high efficiency.

[0004] The existing technology also uses the melting solidification technology. The melting furnace uses a side-blowing spray gun, that is, a hole is opened on the furnace wall to insert the spray gun, and the fuel enters the molten pool from the side. The side-blowing type generally requires the insertion of multiple spray guns, and the depth of the spray gun inserted into the molten pool cannot be adjusted. In the event of a dead furnace, there is no good solution, and opening more holes in the furnace wall increases the risk of charge leakage.

[0005] In addition, the existing fuel-fired melting furnace technology is characterized by a simple structure, but is not sophisticated enough for the smelting of valuable metals, and a relatively high ascending flue needs to be set up on the top of the melting furnace, which places relatively high requirements on the furnace structure and factory building. Utility Model Content

[0006] In view of the defects of existing fuel-type melting furnace technology, such as the inability to carry out fine smelting of valuable metals, the need to set up a higher ascending flue, the inability to adjust the depth of the spray gun inserted into the molten pool and the increased risk of charge leakage, as well as the high energy consumption of plasma melting technology and the high frequency of furnace cover maintenance, the utility model provides a composite melting furnace.

[0007] The technical solution provided by the utility model is:

[0008] A composite melting furnace comprises a melting furnace and a material inlet; the material inlet is located on a furnace cover of the melting furnace; and further comprises a fuel spray gun and a plasma generator, the fuel spray gun and the plasma generator share a socket; the socket is located on the furnace cover of the melting furnace and is adjacent to the material inlet;

[0009] An ascending flue is located at the furnace cover of the melting furnace and forms an angle with the furnace cover of the melting furnace; the angle range is 50° to 70°; the ascending flue is adjacent to the material inlet or socket.

[0010] Preferably, it also includes a pressure control system and a lifting system; the pressure control system is used to drive the lifting system to drive the spray gun or plasma generator to rise and fall.

[0011] Preferably, the lifting system is connected to the fuel spray gun; the pressure control system is oxygen-enriched air pressure control; the oxygen-enriched air pressure control is used to drive the lifting system to drive the fuel spray gun to lift and lower.

[0012] Preferably, the lifting system is connected to the plasma generator; the pressure control system is electrode carrier gas pressure control; the electrode carrier gas pressure control is used to drive the lifting system to drive the plasma generator to lift and lower.

[0013] Preferably, it also includes a temperature detection system and a power control system; the power control system is connected to the fuel spray gun or the plasma generator; the temperature detection system is used to detect the temperature in the furnace of the melting furnace, and the power control system adjusts the fuel delivery rate in the fuel spray gun or the input power of the plasma generator according to the detected temperature.

[0014] Preferably, the ascending flue is connected to an external pipe; at least one induced draft fan is connected to the pipe; at least one flue gas pressure detector is arranged between the ascending flue and the induced draft fan; the flue gas pressure detector is used to detect the pressure at the top of the melting furnace, and the induced draft fan adjusts its own power according to the detected pressure.

[0015] Preferably, the inner wall of the melting furnace is in an inverted trapezoidal shape, and the cross section is waist-shaped.

[0016] Preferably, the melting furnace cover is also provided with a spare socket; the socket and the spare socket are used together to enable the fuel spray gun and the plasma generator to work simultaneously.

[0017] Preferably, the fuel spray gun is a concentric sleeve structure, in which a gas pipeline, an oxygen-enriched pipeline and an air pipeline are sequentially sleeved from the inside to the outside.

[0018] Preferably, the socket and the spare socket are both connected to a nitrogen pipeline; and the side walls of the socket and the spare socket are provided with gas sealing holes for releasing nitrogen.

[0019] Compared with the prior art, the technical solution provided by the utility model has the following beneficial effects:

[0020] The utility model discloses a composite melting furnace, which adopts top blowing to introduce fuel or inserts a plasma generator at the top of the melting furnace, so that the fuel spray gun and the plasma generator can be shared. In special cases, the spare socket is activated to use the fuel spray gun and the plasma generator at the same time. It can not only reflect the advantages of the combustion melting furnace, but also realize mass production without the need to refine the valuable metals; it can also reflect the advantages of the plasma melting furnace, perform high-temperature melting, and realize the refining of the valuable metals.

[0021] In addition, the pressure transmitter and the lifting system form a control loop to adjust the depth of the fuel spray gun or plasma generator inserted into the furnace. The inclined rising flue greatly reduces the height of the flue and reduces the pressure drop of the flue. At the same time, the smoke generated during the melting process sinks into the molten pool in the rising flue; the combustible gas can also be burned in the rising flue, which also has the function of a secondary combustion chamber.

[0022] The inner wall of the melting furnace is in an inverted trapezoidal shape with a waist-shaped cross-section, which can improve the uniform distribution of the temperature field in the furnace and is more conducive to the melting of hazardous waste. The slag splashes onto the inner wall of the furnace with an inverted trapezoidal structure and then flows down, which can more easily form slag protection for the refractory material and reduce the formation of secondary fly ash; the enlarged volume of the upper gas phase space can reduce the thermal intensity of the top and reduce the frequency of furnace cover maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic diagram of the overall structure of a composite melting furnace using a fuel spray gun in one embodiment of the present application;

[0024] Figure 2 This is a front view of a composite melting furnace cover in one embodiment of the present application;

[0025] Figure 3 This is a top view of a composite melting furnace cover in one embodiment of the present application;

[0026] Figure 4 This is a schematic diagram of the overall structure of a lifting system when a composite melting furnace uses a plasma generator in an embodiment of the present application;

[0027] Figure 5 It is a schematic diagram of the concentric sleeve structure of a fuel spray gun in one embodiment of the present application.

[0028] Explanation of the symbols in the schematic diagram:

[0029] Material inlet 1; fuel spray gun 2, gas pipeline 21, oxygen-enriched pipeline 22, air pipeline 23; plasma generator 3; socket 4; ascending flue 5; lifting system 6, clamping device 61; oxygen-enriched air pressure control 7; electrode carrier gas pressure control 8; temperature detection system 9; power control system 10; flue gas pressure detector 11; induced draft fan 12; spare socket 13; gas sealing hole 14. DETAILED DESCRIPTION

[0030] In order to further understand the content of the utility model, the utility model is described in detail in conjunction with the drawings and embodiments.

[0031] The structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the present invention, so they have no substantial technical significance. Any modification of the structure, change of the proportion relationship or adjustment of the size, without affecting the effects and purposes that can be achieved by the present invention, should still fall within the scope of the technical content disclosed by the present utility model. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and so on quoted in this specification are only for the convenience of description, and are not used to limit the scope of implementation. The change or adjustment of their relative relationship should also be regarded as the scope of implementation of the present invention without substantially changing the technical content.

[0032] Example 1

[0033] In this embodiment, the present application proposes a composite melting furnace, including a melting furnace, a material inlet 1, a fuel spray gun 2, a plasma generator 3, a socket 4, an ascending flue 5, and a lifting system 6. Among them, the material inlet 1, the socket 4, and the ascending flue 5 are located on the furnace cover of the melting furnace, and are opened at the top of the melting furnace, and the insertion depth of the fuel spray gun 2 or the plasma generator 3 can be adjusted to make the material melting process smoother.

[0034] The fuel spray gun 2 and the plasma generator 3 share the socket 4 and the lifting system 6, which can not only reflect the advantages of the combustion melting furnace and realize mass production without the need to refine the valuable metals, but also reflect the advantages of the plasma melting furnace and perform high-temperature melting to realize the refining of valuable metals.

[0035] Generally, a top-blown fuel melting furnace needs to be equipped with a relatively high ascending flue to promptly discharge smoke and combustible gases in the furnace. The present application provides an ascending flue 5, which forms an angle with the furnace cover of the melting furnace, and the angle range is 50° to 70°. Preferably, an angle of 60° is optimal. The smoke generated during the melting process gradually sinks into the molten pool in the ascending flue 5, and the combustible gases can also be burned out in the ascending flue 5, which has the function of a secondary combustion chamber. The ascending flue 5 reduces the resistance of the smoke flowing through the flue and effectively reduces the height of the equipment.

[0036] The fuel spray gun 2 is provided with an oxygen-enriched air pipeline, and there are at least three of these pipelines, which respectively introduce air, oxygen-enriched air and fuel gas. The fuel spray gun 2 is a concentric sleeve structure, and the fuel gas pipeline 21, the oxygen-enriched pipeline 22 and the air pipeline 23 are sequentially sleeved from the inside to the outside. The oxygen-enriched air pressure control 7 is arranged between the oxygen-enriched air pipeline and the lifting system 6, and is used to drive the lifting system 6 to drive the fuel spray gun 2 to rise and fall.

[0037] The plasma generator 3 includes a graphite electrode and a bottom electrode, and is externally connected to a short network. The plasma generator 3 is provided with an electrode carrier gas pipeline corresponding to the electrode carrier gas, and the electrode carrier gas is introduced into the plasma generator 3 through the pipeline. The electrode carrier gas pressure control 8 is provided between the electrode carrier gas pipeline and the lifting system 6, and is used to drive the lifting system 6 to drive the plasma generator 3 to rise and fall.

[0038] In addition, a nitrogen pipeline is also provided, and both the socket 4 and the socket 13 are connected to the nitrogen pipeline. When the melting furnace is started, nitrogen is continuously introduced. The side walls of the socket 4 and the socket 13 are provided with gas sealing holes 14 for releasing nitrogen. The nitrogen pipeline and the gas sealing holes 14 are used to seal the socket 4 and the spare socket 13 with nitrogen.

[0039] The temperature detection system 9 is used to detect the temperature in the furnace of the melting furnace and feed back the detected temperature to the power control system 10. The power control system 10 is connected to the fuel spray gun 2 or the plasma generator 3. The power control system 10 adjusts the fuel delivery rate in the fuel spray gun 2 or the input power of the plasma generator 3 according to the detected temperature.

[0040] The ascending flue 5 is connected to an external pipeline; at least one induced draft fan 12 is connected to the pipeline, and the flue gas discharged from the ascending flue 5 is further purified by the waste heat recovery and flue gas purification system, and then discharged through the chimney through the induced draft fan 12. At least one flue gas pressure detector 11 is arranged between the ascending flue 5 and the induced draft fan 12, which is used to detect the pressure on the top of the melting furnace and feed the detected pressure back to the induced draft fan 12, and the induced draft fan 12 adjusts its own power according to the detected pressure.

[0041] In this embodiment, preferably, two induced draft fans 12 are arranged in parallel. In normal operation, the two induced draft fans 12 are opened at 50% each at the same low frequency; if one fails, the other is adjusted to a normal frequency and operates alone.

[0042] The inner wall of the melting furnace is set in an inverted trapezoidal shape. The molten slag splashes onto the inner wall of the trapezoidal structure and then flows down, which is easier to form slag protection for the refractory material. The cross section is waist-shaped, which can improve the uniform distribution of the temperature field in the furnace, reduce the frequency of furnace cover maintenance, and is more conducive to the melting process.

[0043] Example 2

[0044] In this embodiment, the basic structure is the same as that of the embodiment 1, except that the furnace cover of the melting furnace is further provided with a spare socket 13 and a spare lifting system. When the fuel spray gun 2 and the plasma generator 3 need to work simultaneously, the socket 4 and the spare socket 13 are respectively inserted into the fuel spray gun 2 and the plasma generator 3, and at the same time, the fuel spray gun 2 is connected to the lifting system 6, and the plasma generator 3 is connected to the spare lifting system. At this time, the fuel spray gun 2 and the plasma generator 3 melt the material simultaneously.

[0045] Example 3

[0046] A composite melting furnace operation steps are as follows:

[0047] Step 1: Put a proper amount of metal and slag-forming agent into the melting furnace, fix the fuel spray gun 2 with the clamping device 61 configured by the lifting system 6, insert it from the socket 4 and start working, first melt to form a molten pool.

[0048] Step 2: When plasma refining is required, the clamping device 61 moves upward along the lifting system 6 to lift the fuel spray gun 2. After the clamping device 61 fixes the plasma generator 3, it moves downward along the lifting system to insert the plasma generator 3 into the socket 4, and then plasma melting is carried out in the melting furnace, thereby eliminating the need for depletion equipment such as the electric heating front bed.

[0049] Step 3: During the replacement of the plasma generator 3, the fuel spray gun 2 can be used to supplement the furnace to maintain the temperature in the furnace.

[0050] Step 4: In the melting furnace, slag and metal are separated into layers due to density differences. Slag with low density is discharged from the slag outlet at the bottom of the furnace, quenched in a water pool to become glass slag and collected, and metal with high density is discharged from the metal outlet at the bottom of the furnace.

[0051] The above schematically describes the present invention and its implementation methods, which are not restrictive. The drawings show only one implementation method of the present invention, and the actual structure is not limited thereto. Therefore, if ordinary technicians in this field are inspired by it and design structural methods and embodiments similar to the technical solution without creativity without departing from the purpose of the present invention, they should all fall within the protection scope of the present invention.

Claims

1. A composite melting furnace, comprising a melting furnace and a material inlet (1); the material inlet (1) is located on a furnace cover of the melting furnace; Features: Also includes, A fuel spray gun (2) and a plasma generator (3), wherein the fuel spray gun (2) and the plasma generator (3) share a common socket (4); the socket (4) is located on the furnace cover of the melting furnace, adjacent to the material inlet (1); An ascending flue (5), the ascending flue (5) is located on the furnace cover of the melting furnace and forms an angle with the furnace cover of the melting furnace; the angle range is 50° to 70°; the ascending flue (5) is adjacent to the material inlet (1) or the socket (4).

2. A composite melting furnace according to claim 1, Features: It also includes a pressure control system and a lifting system (6); the pressure control system is used to drive the lifting system (6) to drive the spray gun (2) or the plasma generator (3) to move up and down.

3. A composite melting furnace according to claim 2, Features: The lifting system (6) is connected to the fuel spray gun (2); the pressure control system is an oxygen-enriched air pressure control (7); the oxygen-enriched air pressure control (7) is used to drive the lifting system (6) to drive the fuel spray gun (2) to move up and down.

4. A composite melting furnace according to claim 2, Features: The lifting system (6) is connected to the plasma generator (3); the pressure control system is an electrode carrier gas pressure control (8); the electrode carrier gas pressure control (8) is used to drive the lifting system (6) to drive the plasma generator (3) to move up and down.

5. A composite melting furnace according to claim 1, Features: It also includes a temperature detection system (9) and a power control system (10); the power control system (10) is connected to the fuel spray gun (2) or the plasma generator (3); the temperature detection system (9) is used to detect the temperature in the furnace of the melting furnace, and the power control system (10) adjusts the injection rate of the fuel in the fuel spray gun (2) or the input power of the plasma generator (3) according to the detected temperature.

6. A composite melting furnace according to claim 1, Features: The ascending flue (5) is connected to an external pipeline; the pipeline is connected to at least one induced draft fan (12); at least one flue gas pressure detector (11) is arranged between the ascending flue (5) and the induced draft fan (12); the flue gas pressure detector (11) is used to detect the pressure at the top of the melting furnace, and the induced draft fan (12) adjusts its own power according to the detected pressure.

7. The composite melting furnace according to claim 1, Features: The inner wall of the melting furnace is in an inverted trapezoidal shape, and the cross section is in a waist shape.

8. The composite melting furnace according to claim 1, Features: The furnace cover of the melting furnace is also provided with a spare socket (13); the socket (4) and the spare socket (13) enable the fuel spray gun (2) and the plasma generator (3) to work simultaneously.

9. The composite melting furnace according to claim 1, Features: The fuel spray gun (2) is a concentric sleeve structure, with a gas pipeline (21), an oxygen-enriched pipeline (22) and an air pipeline (23) being sequentially sleeved from the inside to the outside.

10. The composite melting furnace according to claim 8, Features: The socket (4) and the spare socket (13) are both connected to a nitrogen pipeline; and a gas sealing hole (14) for releasing nitrogen is provided on the side walls of the socket (4) and the spare socket (13).

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