A plasma melting furnace

Abstract

The present invention belongs to the technical field of waste treatment and discloses a plasma melting furnace, which includes an upper furnace structure, a lower furnace structure and a driving device. A negative pressure furnace chamber is formed between the upper furnace structure and the lower furnace structure, and the lower furnace structure can be driven by the driving device to rotate relative to the upper furnace structure; the upper furnace structure is provided with a feed port communicating with the negative pressure furnace chamber, a flue gas outlet and a plasma torch passing through the upper furnace structure; the lower furnace structure is provided with a slag discharge port communicating with the negative pressure furnace chamber. By setting the lower furnace structure to be rotatable relative to the upper furnace structure, the waste materials entering the negative pressure furnace chamber through the feed port can be evenly distributed at the bottom of the negative pressure furnace chamber. At the same time, the plasma torch can be circulated and evenly sprayed on the waste materials at the bottom of the negative pressure furnace chamber, and the waste materials and the heat of the plasma torch can be evenly distributed, improving the energy utilization rate and the processing capacity of the plasma melting furnace, and further increasing the processing volume of the plasma melting furnace.

Description

Technical Field

[0001] The present invention relates to the technical field of waste disposal, and particularly to a plasma melting furnace. Background Art

[0002] With the increasing number of waste incineration power plants, the output of incineration fly ash is also increasing. At present, the main treatment methods are cement solidification and reagent stabilization. After the solidified fly ash meets the requirements of the leaching toxicity standard, it can be landfilled as general waste. However, with the improvement of landfill standards, for fly ash with a chloride ion content exceeding 10%, pretreatment must be carried out when using the cement solidification method to reduce problems such as the mechanical properties of the cured blocks and the leaching of heavy metal ions in the later stage. This greatly improves the requirements for the construction and operation of fly ash disposal sites, resulting in increased costs and limiting the application of this method. Therefore, plasma melting technology has been developed. Using plasma melting technology, the vitreous product has an extremely low permeability and a significant reduction in volume. The vitreous body that meets the requirements can be used as building materials such as concrete aggregates and subgrade materials. However, the existing technology uses a plasma melting furnace with a fixed structure to melt waste, resulting in uneven distribution of waste materials and heat, leading to low energy utilization rate, low throughput, and low melting efficiency. Summary of the Invention

[0003] The purpose of the present invention is to provide a plasma melting furnace to solve the problem of uneven distribution of waste materials and heat, resulting in low energy utilization rate and low throughput.

[0004] To achieve this purpose, the present invention adopts the following technical solutions:

[0005] A plasma melting furnace includes an upper furnace structure, a lower furnace structure, and a driving device. A negative pressure furnace chamber is formed between the upper furnace structure and the lower furnace structure, and the lower furnace structure can be driven by the driving device to rotate relative to the upper furnace structure; the upper furnace structure is provided with a feed port communicating with the negative pressure furnace chamber, a flue gas outlet, and a plasma torch passing through the upper furnace structure; the lower furnace structure is provided with a slag discharge port communicating with the negative pressure furnace chamber.

[0006] Preferably, the upper furnace structure includes an upper furnace body and a furnace cover. The upper furnace body is sealed and rotatably connected to the lower furnace structure, and the furnace cover is sealed and covers the upper part of the upper furnace body.

[0007] Preferably, the plasma torch includes a first plasma torch, and the first plasma torch passes through the center of the furnace cover.

[0008] Preferably, the plasma torch further includes a second plasma torch, which is disposed at a non - central position of the furnace cover, and the second plasma torch and the feed inlet are located on the same circumference, and the center of the circumference coincides with the center of the furnace cover.

[0009] Preferably, when there are multiple second plasma torches and multiple feed inlets, the multiple second plasma torches and the multiple feed inlets are located on the same circumference, and the second plasma torches and the feed inlets are alternately and evenly arranged;

[0010] Alternatively, the multiple second plasma torches are respectively located on different circumferences with the same center, and each second plasma torch is set in a group with one feed inlet and is located on the same circumference;

[0011] Alternatively, the multiple second plasma torches are respectively located on different circumferences with the same center, and each second plasma torch is set in a group with multiple feed inlets and is evenly arranged on the same circumference.

[0012] Preferably, the included angle formed by the connection lines between the centers of the second plasma torches on adjacent circumferences and the center of the circle is 180°.

[0013] Preferably, the included angle formed by the connection lines between the center of each second plasma torch and the center of one feed inlet set in a group on the same circumference and the center of the circle is 90°.

[0014] Preferably, the lower end of the upper furnace structure is sleeved outside the upper end of the lower furnace structure;

[0015] Alternatively, the upper end of the lower furnace structure is sleeved outside the lower end of the upper furnace structure.

[0016] Preferably, the slag discharge port is vertically opened at the center of the bottom surface of the lower furnace structure.

[0017] Preferably, the lower furnace structure is fixedly provided with a first runner, the output end of the driving device is connected with a second runner, and the first runner meshes with the second runner.

[0018] Advantages of the present invention: The plasma melting furnace provided by the present invention has an upper furnace structure provided with a feed port communicating with a negative pressure furnace chamber, a flue gas outlet, and a plasma torch passing through the upper furnace structure. The lower furnace structure is provided with a slag discharge port communicating with the negative pressure furnace chamber. The lower furnace structure can be driven by a driving device to rotate relative to the upper furnace structure. By setting the lower furnace structure to be rotatable relative to the upper furnace structure, when treating waste materials, the driving device drives the lower furnace structure to rotate, and the waste materials entering the negative pressure furnace chamber through the feed port of the upper furnace structure can be evenly distributed at the bottom of the negative pressure furnace chamber. At the same time, the plasma torch on the upper furnace structure can be sprayed cyclically and evenly on the waste materials at the bottom of the negative pressure furnace chamber. The heat of the waste materials and the plasma torch can be evenly distributed, improving the energy utilization rate and the processing capacity of the plasma melting furnace, thereby increasing the processing volume of the plasma melting furnace and enhancing the melting efficiency. Description of the Drawings

[0019] Figure 1 is a schematic diagram of the plasma melting furnace provided by the present invention;

[0020] Figure 2 is the first layout diagram of the plasma torch and the feed port in the plasma melting furnace provided by the present invention;

[0021] Figure 3 is the second layout diagram of the plasma torch and the feed port in the plasma melting furnace provided by the present invention;

[0022] Figure 4 is the third layout diagram of the plasma torch and the feed port in the plasma melting furnace provided by the present invention;

[0023] Figure 5 is the fourth layout diagram of the plasma torch and the feed port in the plasma melting furnace provided by the present invention;

[0024] Figure 6 is the fifth layout diagram of the plasma torch and the feed port in the plasma melting furnace provided by the present invention.

[0025] In the figure:

[0026] 100, upper furnace structure; 101, feed port; 102, flue gas outlet; 103, plasma torch; 1031, first plasma torch; 1032, second plasma torch; 104, upper furnace body; 105, furnace cover; 200, lower furnace structure; 201, slag discharge port; 202, first runner; 300, driving device; 301, second runner; 400, negative pressure furnace chamber; 500, sealing device. Detailed Embodiments

[0027] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It can be understood that the specific embodiments described herein are only for explaining the present invention, rather than limiting the present invention. Additionally, it should be noted that for the convenience of description, only the parts related to the present invention rather than all the structures are shown in the drawings.

[0028] In the description of the present invention, unless otherwise clearly defined and limited, the terms "connected", "connected to", and "fixed" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0029] In the present invention, unless otherwise clearly defined and limited, the first feature being "above" or "below" the second feature may include the direct contact between the first and second features, or may include the situation where the first and second features are not in direct contact but in contact through other features therebetween. Moreover, the first feature being "above", "over", and "on top of" the second feature includes that the first feature is directly above and obliquely above the second feature, or merely indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature being "below", "beneath", and "under" the second feature includes that the first feature is directly below and obliquely below the second feature, or merely indicates that the horizontal height of the first feature is lower than that of the second feature.

[0030] In the description of this embodiment, the orientation or positional relationships such as "above", "below", "left", and "right" are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of description and simplifying the operation, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present invention. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.

[0031] This embodiment provides a plasma melting furnace, such as Figure 1As shown in the figure, it includes an upper furnace structure 100, a lower furnace structure 200, and a driving device 300. Among them, a negative-pressure furnace chamber 400 is formed between the upper furnace structure 100 and the lower furnace structure 200. (In a negative-pressure and oxygen-deficient environment, a high-temperature energy source is generated by a plasma torch, so that the organic components in the waste materials entering the negative-pressure furnace chamber 400 are cracked and gasified, converted into crude synthesis gas, and the inorganic components are melted to form harmless vitreous residues, realizing volume reduction, weight reduction, and harmlessness of the waste materials. At the same time, in the negative-pressure state, it can avoid the leakage of the flue gas in the negative-pressure furnace chamber 400.) The lower furnace structure 200 can be driven by the driving device 300 to rotate relative to the upper furnace structure 100. The upper furnace structure 100 can be arranged on a fixed bracket. The upper furnace structure 100 is provided with a feed port 101 communicating with the negative-pressure furnace chamber 400, a flue gas outlet 102 communicating with the negative-pressure furnace chamber 400, and a plasma torch 103 passing through the upper furnace structure 100. The lower furnace structure 200 is provided with a slag discharge port 201 communicating with the negative-pressure furnace chamber 400. When in use, the driving device 300 is started, and the driving device 300 drives the lower furnace structure 200 to rotate relative to the upper furnace structure 100. The feed port 101 conveys waste materials to the negative-pressure furnace chamber 400. As the lower furnace structure 200 rotates, the waste materials are evenly distributed at the bottom of the negative-pressure furnace chamber 400. At the same time, the plasma torch 103 can be sprayed cyclically and evenly on the waste materials at the bottom of the negative-pressure furnace chamber 400, and the waste materials are heated evenly. The waste materials are melted in the negative-pressure furnace chamber 400 to form a high-temperature molten liquid. The generated flue gas is led out through the flue gas outlet 102 and can be sent to the corresponding secondary combustion chamber and flue gas treatment system for flue gas treatment. The high-temperature molten liquid flows out through the slag discharge port 201, and the flowing high-temperature molten liquid can be cooled by a cooling medium (water or air) to form harmless vitreous bodies.

[0032] The plasma torch 103 in this embodiment is preferably a plasma torch device with a switchable mode. In the initial stage of ignition, the waste materials are not melted, and the plasma torch 103 operates in the non-transferred arc mode. When the waste materials are melted, the plasma torch 103 switches to the transferred arc mode. In order to increase the energy utilization efficiency, an electrode can be arranged at a position in the lower furnace structure 200 close to the negative-pressure furnace chamber 400. The plasma torch 103 forms an electrical circuit with the electrode in the transferred arc mode. The electrode can be, but is not limited to, a metal electrode or a graphite electrode.

[0033] The upper furnace structure 100 in this embodiment includes an upper furnace body 104 and a furnace cover 105. The upper furnace body 104 is rotationally and sealingly connected to the lower furnace structure 200. The furnace cover 105 is sealingly covered above the upper furnace body 104. When a failure occurs in the plasma melting furnace, the furnace cover 105 can be removed for repairing the plasma melting furnace, which is convenient for operation. Preferably, the upper furnace body 104 and the furnace cover 105 are connected by bolts, and the contact surface between the upper furnace body 104 and the furnace cover 105 is sealed with heat insulation felts and refractory mud.

[0034] Optionally, the plasma torch 103 includes a first plasma torch 1031 which is disposed through the center of the furnace cover 105, and the first plasma torch 1031 can inject waste materials in the negative-pressure furnace chamber 400. As a preferred technical solution, the first plasma torch 1031 is vertically disposed through the center of the furnace cover 105. By vertically disposing the first plasma torch 1031 relative to the furnace cover 105 and at the center of the furnace cover 105, the first plasma torch 1031 can inject towards the center of the waste materials in the negative-pressure furnace chamber 400, so that the waste materials in the negative-pressure furnace chamber 400 are heated simultaneously, enhancing the heating efficiency of the waste materials.

[0035] Further, the plasma torch 103 further includes a second plasma torch 1032 which is disposed through a non-center position of the furnace cover 105. The second plasma torch 1032 and the feed inlet 101 are located on the same circumference, and the center of the circumference coincides with the center of the furnace cover 105. By arranging the second plasma torch 1032 and the feed inlet 101 on the same circumference, the waste materials entering the negative-pressure furnace chamber 400 through the feed inlet 101 can be better and evenly distributed at the bottom of the negative-pressure furnace chamber 400, and the second plasma torch 1032 can heat the waste materials in the negative-pressure furnace chamber 400 in time, further improving the heating efficiency of the waste materials and at the same time improving the energy utilization rate. As a preferred technical solution, the second plasma torch 1032 is vertically disposed relative to the furnace cover 105.

[0036] Furthermore, a plurality of second plasma torches 1032 can be provided, and a plurality of feed inlets 101 can be provided. In one embodiment, when there are a plurality of second plasma torches 1032 and a plurality of feed inlets 101, as Figure 2 shown, the plurality of second plasma torches 1032 and the plurality of feed inlets 101 are located on the same circumference, and the second plasma torches 1032 and the feed inlets 101 are alternately and evenly arranged to simultaneously improve the feeding efficiency and heating efficiency of the plasma melting furnace.

[0037] In another embodiment, when there are a plurality of second plasma torches 1032 and a plurality of feed inlets 101, as Figure 3 shown, the plurality of second plasma torches 1032 are respectively located on different circumferences with the same center. Each second plasma torch 1032 and a feed inlet 101 are set in a group and the second plasma torch 1032 and the feed inlet 101 are located on the same circumference, enhancing the feeding effect while increasing the heating area and further improving the feeding efficiency and heating efficiency.

[0038] In another embodiment, when there are a plurality of second plasma torches 1032 and a plurality of feed inlets 101, as Figure 4As shown, multiple second plasma torches 1032 are respectively located on different circumferences with the same center. Each second plasma torch 1032 is evenly arranged in groups with multiple feed ports 101 and is located on the same circumference. By arranging them in groups with multiple feed ports 101, while ensuring the heating efficiency, the feeding efficiency is further improved to enhance the processing capacity of the waste materials in the plasma melting furnace.

[0039] As a preferred technical solution, as Figure 5 and Figure 6 shown, when each second plasma torch 1032 is located on different circumferences with the same center, the angle formed by the connection lines between the centers of the second plasma torches 1032 on two adjacent circumferences and the center of the circle is 180°. The number of second plasma torches 1032 can be controlled while maintaining the heating efficiency, avoiding the situation of waste of some heat caused by too many second plasma torches 1032, and at the same time saving the production cost of the plasma melting furnace. Further, the angle formed by the connection lines between the center of each second plasma torch 1032 and the center of a feed port 101 arranged in groups on the same circumference and the center of the circle is 90°, so as to achieve the balance between meeting the requirements of material feeding efficiency and heating efficiency and controlling the cost. Further, as Figure 5 shown, when the lower furnace structure 200 rotates counterclockwise, the second plasma torches 1032 on the same circumference are arranged at the counterclockwise position close to the feed port 101 on the circumference; on the contrary, as Figure 6 shown, when the lower furnace structure 200 rotates clockwise, the second plasma torches 1032 on the same circumference are arranged at the clockwise position close to the feed port 101 on the circumference, so that the waste materials entering from the feed port 101 are heated by the second plasma torches 1032 immediately after entering the negative pressure furnace chamber 400, further enhancing the heating effect.

[0040] The lower end of the upper furnace structure 100 in this embodiment can be sleeved outside the upper end of the lower furnace structure 200, or the upper end of the lower furnace structure 200 can be sleeved outside the lower end of the upper furnace structure 100; the diameter of the upper part in the negative pressure furnace chamber 400 can be the same as that of the lower part. At this time, the negative pressure furnace chamber 400 is in a shape similar to a "cylinder", or the diameter of the upper part in the negative pressure furnace chamber 400 is smaller than that of the lower part. At this time, the negative pressure furnace chamber 400 is in a shape similar to a "frustum of a cone", or the diameter of the upper part in the negative pressure furnace chamber 400 is larger than that of the lower part, forming a shape similar to an "inverted frustum of a cone". When the negative pressure furnace chamber 400 is in a shape similar to an "inverted frustum of a cone", it is convenient for the high-temperature molten liquid to flow out through the slag discharge port 201. In order to improve the discharge efficiency of the slag discharge port 201, the slag discharge port 201 is vertically opened at the center of the bottom surface of the lower furnace structure 200, and the slag discharge port 201 located at the center of the bottom surface of the lower furnace structure 200 can improve the discharge effect, avoid the situation that part of the high-temperature molten liquid cannot flow out smoothly, and ensure the smoothness of the discharge of the slag discharge port 201. In order to better seal between the upper furnace structure 100 and the lower furnace structure 200, a sealing device 500 is provided at the position where the upper furnace structure 100 and the lower furnace structure 200 are in rotational contact. The sealing device 500 can be, but is not limited to, a spring lever combination seal, a graphite block seal or a fish scale seal.

[0041] Optionally, the lower furnace structure 200 is fixedly provided with a first runner 202, the output end of the driving device 300 is connected with a second runner 301, the first runner 202 meshes with the second runner 301, the output end of the driving device 300 drives the second runner 301 to rotate, when the second runner 301 rotates, it drives the first runner 202 meshing with it to rotate, and when the first runner 202 rotates, it drives the lower furnace structure 200 fixedly provided with it to rotate, so as to ensure that the driving device 300 can stably drive the lower furnace structure 200 to rotate. As a preferred technical solution, the first runner 202 can be fixedly provided on the side wall of the lower furnace structure 200, or can be fixedly provided at the bottom end of the lower furnace structure 200. When the first runner 202 is provided at the bottom end of the lower furnace structure 200, the first runner 202 is provided with a through hole communicating with the slag discharge port 201 to facilitate the discharge of the high-temperature molten liquid.

[0042] The working process of the plasma melting furnace provided in this embodiment is as follows:

[0043] Start the driving device 300. The driving device 300 drives the lower furnace structure 200 to rotate relative to the upper furnace structure 100. The waste materials enter the negative pressure furnace chamber 400 through the feed inlet 101. As the lower furnace structure 200 rotates, the waste materials are evenly distributed at the bottom of the negative pressure furnace chamber 400. At the same time, the first plasma torch 1031 and the second plasma torch 1032 can be sprayed cyclically and evenly on the waste materials at the bottom of the negative pressure furnace chamber 400. The waste materials are evenly heated, and the waste materials undergo a melting reaction in the negative pressure furnace chamber 400 to form a high-temperature molten liquid. The generated flue gas is led out through the flue gas outlet 102. The led-out flue gas can be sent to the corresponding secondary combustion chamber and flue gas treatment system for flue gas treatment. The high-temperature molten liquid flows out through the slag discharge port 201. The flowing high-temperature molten liquid can be cooled by a cooling medium again. The cooled high-temperature molten liquid forms harmless glassy bodies.

[0044] Obviously, the above-mentioned embodiments of the present invention are merely examples for clearly explaining the present invention, rather than limitations on the implementation manners of the present invention. For those of ordinary skill in the art, various obvious changes, re-adjustments and substitutions can be made without departing from the protection scope of the present invention. It is not necessary and impossible to enumerate all the implementation manners here. Any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the claims of the present invention.

Claims

1. A plasma melting furnace, characterized in that, it includes an upper furnace structure (100), a lower furnace structure (200) and a driving device (300). A negative pressure furnace chamber (400) is formed between the upper furnace structure (100) and the lower furnace structure (200), and the lower furnace structure (200) can be driven by the driving device (300) to rotate relative to the upper furnace structure (100); the upper furnace structure (100) is provided with a feed inlet (101) communicating with the negative pressure furnace chamber (400), a flue gas outlet (102) and a plasma torch (103) passing through the upper furnace structure (100); the lower furnace structure (200) is provided with a slag discharge port (201) communicating with the negative pressure furnace chamber (400); the upper furnace structure (100) includes an upper furnace body (104) and a furnace cover (105). The upper furnace body (104) is sealingly and rotatably connected to the lower furnace structure (200), and the furnace cover (105) is sealingly covered above the upper furnace body (104); the plasma torch (103) includes a first plasma torch (1031), and the first plasma torch (1031) is arranged at the center of the furnace cover (105); the plasma torch (103) further includes a second plasma torch (1032). The second plasma torch (1032) is arranged at a non - central position of the furnace cover (105), and the second plasma torch (1032) and the feed inlet (101) are located on the same circumference, and the center of the circumference coincides with the center of the furnace cover (105).

2. The plasma melting furnace according to claim 1, characterized in that, when both the second plasma torch (1032) and the feed inlet (101) are multiple, the multiple second plasma torches (1032) and the multiple feed inlets (101) are located on the same circumference, and the second plasma torches (1032) and the feed inlets (101) are alternately and evenly arranged; or, the multiple second plasma torches (1032) are respectively located on different circumferences with the same center. Each second plasma torch (1032) is set in a group with one feed inlet (101) and is located on the same circumference; or, the multiple second plasma torches (1032) are respectively located on different circumferences with the same center. Each second plasma torch (1032) is set in a group with multiple feed inlets (101) and is evenly arranged on the same circumference.

3. The plasma melting furnace according to claim 2, characterized in that, the included angle formed by the connection lines between the centers of the second plasma torches (1032) on two adjacent circumferences and the center of the circle is 180°.

4. The plasma melting furnace according to claim 3, characterized in that, the included angle formed by the connection lines between the center of each second plasma torch (1032) and the center of one feed inlet (101) set in a group on the same circumference and the center of the circle is 90°.

5. The plasma melting furnace according to any one of claims 1 - 4, characterized in that, The lower end of the upper furnace structure (100) is sleeved outside the upper end of the lower furnace structure (200); Alternatively, the upper end of the lower furnace structure (200) is sleeved outside the lower end of the upper furnace structure (100).

6. The plasma melting furnace according to any one of claims 1-4, characterized in that, The slag discharge port (201) is vertically opened at the center of the bottom surface of the lower furnace structure (200).

7. The plasma melting furnace according to any one of claims 1-4, characterized in that, The lower furnace structure (200) is fixedly provided with a first runner (202), the output end of the driving device (300) is connected with a second runner (301), and the first runner (202) meshes with the second runner (301).

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