Fully-closed tail gas recovery fixed type silicon carbide smelting furnace

Abstract

The utility model discloses a fully-closed tail gas recovery fixed type silicon carbide smelting furnace which comprises an end wall, a side wall and a furnace hearth, an electrode is embedded in the end wall, and the end wall embedded with the electrode is connected with the fixed type side wall and the furnace hearth to form a fully-closed groove-shaped furnace body with an open upper opening; the groove-shaped furnace body is filled with furnace materials, a film pad is laid on the material face of the furnace materials, the film pad is integrally covered with an airtight film cover, a circle of closed annular sealing belt is arranged in the length direction of the top of the side wall and the length direction of the waist portion of the outer side of the end wall, and the four edges of the film cover extend to the annular sealing belt and are tightly connected with the annular sealing belt in an airtight mode. The fixed silicon carbide smelting furnace is totally closed, valuable tail gas containing carbon monoxide and the like is collected, the problem that smelting tail gas emission in the silicon carbide industry does not reach the standard is solved, and the collected tail gas is used for comprehensive utilization of gas power generation, coal chemical industry rear sections and the like.

Description

TECHNICAL FIELD

[0001] The utility model relates to the production technical field of silicon carbide industry, concretely is a kind of full-closed tail gas recovery fixed silicon carbide smelting furnace. BACKGROUND

[0002] The traditional fixed silicon carbide smelting furnace is like a rectangular groove in shape, which is a surrounding body composed of two fixed end walls respectively inlaid with positive and negative electrodes and two groups of detachable gas-permeable side walls, and the bottom of the surrounding body is a hearth built with refractory bricks. Two groups of graphite electrodes penetrate the end walls and go deep into the hearth, and a special graphite powder core body is only provided between the electrodes to provide an electrically conductive path, which generates a lot of heat when powered on. The surrounding body is filled with a mixture of silica raw materials, petroleum coke, anthracite and other materials around the core body, and the outside of the mixture is heat preservation material. During silicon carbide smelting, the resistance furnace is powered, the core body temperature rises, and after reaching a certain high temperature, heat is transferred to the surrounding mixture through the surface of the core body, causing a reaction to generate silicon carbide, and the tail gas containing carbon monoxide, hydrogen and other components is overflowed and burned on the surface of the furnace. The existing silicon carbide smelting process adopts an environmental protection mode of "furnace surface igniting tail gas-gas collection hood collecting high-temperature flue gas-flue gas purification system dust removal and desulfurization-organized external discharge", which is a semi-closed smelting method. The gas leakage points of the gas collection hood are many, and according to the atmospheric pollutant emission standard of the silicon carbide industry, the actual oxygen content in the flue gas is very high, and it is difficult to meet the emission standard of the benchmark oxygen content. Therefore, the defects of the traditional fixed silicon carbide smelting furnace are not environmentally friendly and high energy consumption.

[0003] In this regard, Chinese patent application No. CN201810986151.7 discloses an "environment-friendly and energy-saving mountain-shaped silicon carbide smelting tail gas recovery device and recovery method, characterized in that: 1. The device has two end walls, the outer side end face of the end wall is attached with a gas-impermeable layer, and a first sealing groove is arranged at the top of the end wall; 2. A plurality of partitions are arranged in the gas collection chamber along the length direction thereof to separate the gas collection chamber into a plurality of independent gas collection cavities; 3. A gas-permeable layer is also attached to the side wall of the gas collection wall in contact with the reaction body to cover the end face of the gas-permeable hole; 4. A gas-impermeable film is covered on the outer surface of the reaction body, the front and rear ends of the gas-impermeable film are embedded in the first sealing groove, and the left and right ends of the gas-impermeable film are embedded in the second sealing groove." In view of the features of the patent, the following shortcomings exist: 1. A first sealing groove is arranged at the top of the end wall. Since the end wall is higher than the side wall, and the top of the end wall is mostly arc-shaped or trapezoidal, it is difficult to seal the film and the end wall, especially the sealing at the junction of the end wall and the side wall, which is prone to gas leakage; 2. The gas collection chamber is divided into a plurality of independent gas collection cavities, which is prone to uneven pressure between the gas collection cavities and the film covering the furnace surface, and the places with large pressure difference are prone to gas leakage; 3. A gas-permeable layer is also attached to the side wall of the gas collection wall in contact with the reaction body. In actual production, the gas-permeable layer is directly in contact with the material and is prone to damage; 4. A gas-impermeable film is covered on the outer surface of the reaction body, which directly contacts the film and the material. On the one hand, the film is prone to being punctured by sharp objects of the material, and on the other hand, the film is prone to being burned through by high-temperature tail gas escaping from the furnace. Silicon carbide smelting furnaces can be divided into fixed furnaces, movable furnaces, U-shaped furnaces, and mountain-shaped furnaces according to their structural forms. Patent No. CN201810986151.7 only discloses an "environment-friendly and energy-saving mountain-shaped silicon carbide smelting tail gas recovery device and recovery method" for mountain-shaped furnaces.

[0004] In addition, the Chinese patent application No. CN201811257006.1 discloses "a silicon carbide smelting furnace for collecting tail gas, which provides a silicon carbide smelting furnace for collecting tail gas. The smelting furnace is composed of an end wall, a side wall and a furnace bottom. The end wall, the side wall and the furnace bottom form a sealed box body without a cover, which is used to load the smelting silicon carbide furnace charge. The upper part of the furnace charge is sealed by a plastic cloth, and the plastic cloth is sealed on the upper edge of the box body to seal the furnace body. An exhaust pipe is arranged on the smelting furnace, and a fan is used to exhaust the gas in the furnace to achieve tail gas collection. The side wall is a whole fixed body fixed on the smelting furnace, instead of the traditional scattered movable body. The side wall is air-tight". According to the patent features, the following disadvantages exist: 1. The plastic cloth is sealed on the upper edge of the box body to seal the furnace body. The upper edge of the box body refers to the top of the end wall and the side wall connecting body. Since the end wall is higher than the side wall, and the top of the end wall is mostly arc or trapezoidal, it is difficult to seal the end wall with the plastic cloth, especially the sealing of the joint between the end wall and the side wall, which is prone to air leakage; 2. The exhaust pipe is arranged on the smelting furnace, and the exhaust pipe penetrates the furnace. This method is easy to make the material in the furnace enter the exhaust pipe and block the exhaust pipe. The pressure of the tail gas overflowing from the furnace charge to the exhaust pipe port is not uniform. When the exhaust pipe is connected to the main pipe, the exhaust pipe close to the induced draft fan has a larger negative pressure than the exhaust pipe connected to the main pipe at the end, causing uneven pressure in the whole furnace body, affecting production and causing air leakage; 3. The plastic cloth is sealed on the upper part of the furnace charge by closely adhering to the furnace charge, so that the plastic cloth and the material are in direct contact. The plastic cloth is easily pierced by sharp objects, and the plastic cloth is easily burned by the high-temperature tail gas flowing out of the furnace. Practical new type content

[0005] Therefore, the purpose of the present application is to provide a full-closed tail gas recovery fixed type silicon carbide smelting furnace, which collects valuable tail gas containing carbon monoxide by making the fixed type silicon carbide smelting furnace fully closed. The problem of substandard tail gas emission in the silicon carbide industry is solved, and the collected tail gas is used for comprehensive utilization such as gas power generation and coal chemical industry.

[0006] To solve the above technical problems, according to one aspect of the present application, the present application provides the following technical scheme: a full-closed tail gas recovery fixed type silicon carbide smelting furnace, which comprises an end wall, a side wall and a hearth. The end wall is inlaid with electrodes, and the end wall inlaid with electrodes is connected with the fixed side wall and the hearth to form a full-closed slot type furnace body with an open upper mouth.

[0007] The groove type furnace body is filled with furnace charge, and a film pad is laid on the charge surface of the furnace charge, the film pad is entirely covered with an air-tight film cover, a closed annular sealing band is arranged along the length direction of the top of the side wall and the length direction of the waist of the outer side wall of the end wall, the annular sealing band is seamlessly connected with the end wall and the side wall, the film cover extends to the annular sealing band at four edges, and is air-tightly and closely connected with the annular sealing band, and the film cover is in full air-tight connection with the end wall and the side wall of the groove type furnace body through the annular sealing band.

[0008] A plurality of air guide pipes are arranged along the side wall, and the ends of the plurality of air guide pipes are communicated with the tail gas main pipe.

[0009] As a preferred scheme of the full-closed tail gas recovery fixed type silicon carbide smelting furnace, the side wall is composed of a structure sealing layer, a pressure regulating cavity layer and a gas permeable dust separation layer from outside to inside, and the annular sealing band and the operation platform are arranged at the top of the side wall, the pressure regulating cavity layer penetrates along the length direction of the side wall, the pressure of the tail gas collected to the cavity layer is balanced, the pressure of the furnace surface film cover and the atmosphere is kept balanced, and thus the tail gas pressure in the furnace body is facilitated to be controlled, and the air leakage phenomenon caused by uneven furnace surface pressure is prevented.

[0010] As a preferred scheme of the full-closed tail gas recovery fixed type silicon carbide smelting furnace, the air guide pipe is communicated with the pressure regulating cavity layer, the gas permeable dust separation layer allows the tail gas overflowing from the furnace charge to permeate into the pressure regulating cavity layer, and the plurality of air guide pipes introduce the tail gas collected from the pressure regulating cavity layer into the tail gas main pipe outside the structure sealing layer. The regulating valve and the pressure gauge are installed on the air guide pipe to assist in regulating the pressure balance between the air guide pipes.

[0011] As a preferred scheme of the full-closed tail gas recovery fixed type silicon carbide smelting furnace, the end wall is composed of an end wall heat preservation layer, an end wall structure layer and an end wall refractory layer, and the end wall separates the inner space of the groove type furnace body from the outer space. The end wall heat preservation layer is used for protecting the film cover,

[0012] As a preferred scheme of the full-closed tail gas recovery fixed type silicon carbide smelting furnace, the end wall comprises but is not limited to refractory bricks, or the refractory bricks are inlaid with steel reinforced concrete columns and foundation bottom plates resisting the pressure of the furnace charge.

[0013] As a preferred scheme of the full-closed tail gas recovery fixed type silicon carbide smelting furnace, the top surface of the end wall is provided in a double slope or isosceles trapezoidal type according to the angle of repose of the furnace charge, the slope surface can be provided with steps, and the exposed corners of the end wall, the film pad and the film cover can be rounded to protect the film pad and the film cover.

[0014] As a preferred scheme of the full-closed tail gas recovery fixed type silicon carbide smelting furnace, the annular sealing belt is arranged in a groove shape at the top of the side wall, and the annular sealing belt at the waist region of the end wall is also arranged in a groove shape; the groove-shaped sealing belts of the two end walls and the two side walls are connected with each other, forming a horizontal annular groove-shaped sealing belt around the groove-shaped furnace body; water is filled in the groove-shaped sealing belt; and the membrane cover extends to the water in the groove-shaped sealing belt, so as to form the sealing of the membrane cover by water.

[0015] As a preferred scheme of the full-closed tail gas recovery fixed type silicon carbide smelting furnace, the annular sealing belt is arranged in a groove shape at the top of the side wall, and the annular sealing belt at the waist region of the end wall is also arranged in a groove shape; the groove-shaped sealing belts of the two end walls and the two side walls are connected with each other, forming a horizontal annular groove-shaped sealing belt around the groove-shaped furnace body; water is filled in the groove-shaped sealing belt; and the membrane cover extends to the water in the groove-shaped sealing belt, so as to form the sealing of the membrane cover by water.

[0016] As a preferred scheme of the full-closed tail gas recovery fixed type silicon carbide smelting furnace, the annular sealing belt is arranged in a groove shape at the top of the side wall, and the annular sealing belt at the waist region of the end wall is also arranged in a groove shape; the groove-shaped sealing belts of the two end walls and the two side walls are connected with each other, forming a horizontal annular groove-shaped sealing belt around the groove-shaped furnace body; water is filled in the groove-shaped sealing belt; and the membrane cover extends to the water in the groove-shaped sealing belt, so as to form the sealing of the membrane cover by water.

[0017] The air-permeable dust isolation layer includes but is not limited to masonry with porous bricks, air-permeable bricks or water-permeable bricks; if the masonry with porous bricks is adopted, the air-permeable layer is clamped between two layers of porous brick walls to prevent dust from entering the pressure regulating cavity layer; the holes of the porous bricks are arranged horizontally, and the tail gas is introduced into the pressure regulating cavity layer through the holes and the air-permeable layer.

[0018] As a preferred scheme of the full-closed tail gas recovery fixed type silicon carbide smelting furnace, according to process requirements, a furnace door can be arranged at the side wall, so as to facilitate the entry and exit of equipment such as a furnace discharge machine; a door frame is pre-buried at the position of the side wall; a furnace door sealing belt is arranged at the position of the furnace door; a door frame sealing belt is arranged at the position of the door frame; a furnace door groove-shaped sealing belt is arranged on the door body at the position of the furnace door; a groove-shaped sealing gasket is arranged at the port of the groove-shaped sealing belt; the port of the groove-shaped sealing belt on the side wall is pressed and sealed correspondingly; and the door body at the position of the furnace door is locked and sealed with the side wall through a locking nut.

[0019] Compared with the prior art, the full-closed tail gas recovery fixed type silicon carbide smelting furnace has the following advantages:

[0020] On the basis of traditional fixed type silicon carbide smelting furnace, two groups of detachable gas permeable side walls are improved into fixed type side walls, and two fixed end walls respectively inlaid with positive and negative electrodes, the improved two groups of fixed side walls and the hearth are connected into a full closed type slot type furnace body with open top. The slot type furnace body can be built into ground type, semi-underground type or full-underground type. The end walls, the side walls and the bottom of the hearth are connected with each other by using gas impermeable materials. The length and height of the end walls and the side walls of the slot type furnace body are determined according to the silicon carbide closed furnace process parameters and the loading amount during the whole cycle smelting. After the slot type furnace body is filled with various raw materials according to the silicon carbide smelting process requirements, a film mat is laid on the material surface of the slot type furnace body, and a gas impermeable film cover is integrally covered on the film mat. A closed ring-shaped sealing belt is arranged along the length direction of the top of the side wall and the length direction of the waist of the outer side of the end wall. The ring-shaped sealing belt is seamlessly connected with the end wall and the side wall. The four edges of the film cover extend to the ring-shaped sealing belt and are tightly connected with the ring-shaped sealing belt in a gas impermeable manner. The film cover is fully closed with the end wall and the side wall around the slot type furnace body through the ring-shaped sealing belt, so as to form the full closed smelting production condition of the fixed type silicon carbide smelting furnace, to prevent the explosion hidden danger caused by the external air entering the slot type furnace body, and to convey the tail gas generated during smelting to the rear end processing process through the fan after the tail gas is collected into the main tail gas pipe through the multiple gas guide pipes extending from the side wall. BRIEF DESCRIPTION OF DRAWINGS

[0021] In order to more clearly illustrate the technical scheme of the embodiments of the present application, the present application will be described in detail below with reference to the drawings and detailed embodiments. Obviously, the drawings described below are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor. Among them:

[0022] Figure 1 It is a plan view of the present application;

[0023] Figure 2 It is a schematic view of the Figure 1 A-A section in the present application, showing a closed type between the side walls of the semi-underground slot type furnace body;

[0024] Figure 3 It is a schematic view of the Figure 1 B-B section in the present application, showing a closed type of the end wall of the slot type furnace body;

[0025] Figure 4 It is a schematic view of the Figure 2 structure at D in the present application, showing a closed type of the ring-shaped sealing belt of the side wall and the film cover;

[0026] Figure 5 It is a schematic view of the Figure 2Structure schematic view at middle D, showing a sealing type of the annular sealing band of the side wall and the film cover and the film pad;

[0027] Figure 6 For the Figure 2 Structure schematic view at middle C, showing a combination type of the side wall;

[0028] Figure 7 For the Figure 2 Structure schematic view at middle C, showing another combination type of the side wall;

[0029] Figure 8 Position structure view of the furnace door of the utility model;

[0030] Figure 9 Position structure view of the sealing band of the furnace door of the utility model.

[0031] In the figure: 1, end wall; 2, side wall; 3, hearth; 4, annular sealing band; 5, operation platform; 6, film cover; 7, film pad; 8, furnace charge; 9, electrode; 10, slot type furnace body; 11, end wall insulation layer; 12, end wall structure layer; 13, end wall refractory layer; 21, structure sealing layer; 22, pressure regulating cavity layer; 23, air permeable dust separation layer; 24, air guide pipe; 25, tail gas main pipe; 27, air permeable layer; 61, movable pressing bag; 26, furnace door; 261, furnace door sealing band; 262, door frame sealing band; 263, locking nut; 264, furnace discharge machine; 265, door frame; 266, slot type sealing band of the furnace door. DETAILED DESCRIPTION

[0032] In order to make the above-mentioned purposes, features and advantages of the utility model more apparent, obvious and understandable, the specific embodiments of the utility model will be described in detail below with reference to the drawings.

[0033] In the following description, a lot of specific details are set forth in order to fully understand the utility model, but the utility model can also be implemented in other ways different from the description herein, and persons skilled in the art can make similar generalization without departing from the connotation of the utility model, so the utility model is not limited by the specific embodiments disclosed below.

[0034] Secondly, the utility model is described in detail in combination with the schematic view, and in the detailed description of the embodiments of the utility model, for the convenience of description, the sectional view showing the structure of the device will be partially enlarged without the general proportion, and the schematic view is only an example, which should not limit the scope of protection of the utility model herein. In addition, the three-dimensional spatial dimensions of length, width and depth should be included in actual manufacture.

[0035] In order to make the purposes, technical schemes and advantages of the utility model more clear, the embodiments of the utility model will be described in further detail below in combination with the drawings. In the following description, a lot of specific details are set forth in order to fully understand the utility model, but the utility model can also be implemented in other ways different from the description herein, and persons skilled in the art can make similar generalization without departing from the connotation of the utility model, so the utility model is not limited by the specific embodiments disclosed below.

[0036] This invention provides a fully enclosed, fixed silicon carbide smelting furnace with exhaust gas recovery. Based on a traditional fixed silicon carbide smelting furnace, the two sets of detachable, permeable sidewalls are improved into sealed, fixed sidewalls. Furthermore, the two fixed end walls, each embedded with positive and negative electrodes, the improved two sets of fixed sidewalls, and the furnace bed are interconnected to form a fully enclosed, open-top trough-shaped furnace body. The trough-shaped furnace body can be constructed above ground, semi-underground, or fully underground. The exterior of the end walls and side walls of the trough-shaped furnace body, as well as the bottom of the furnace bed, are connected using an airtight material. The length and height of the end walls and side walls of the trough-shaped furnace body are determined according to the process parameters of the closed silicon carbide furnace and the amount of material loaded during the entire smelting cycle. After the trough-shaped furnace body is filled with various raw materials according to the silicon carbide smelting process requirements, a membrane pad is laid on the material surface of the trough-shaped furnace body, and an airtight membrane cover is then placed over the membrane pad. A closed annular sealing strip is installed along the length of the top of the side wall and the length of the outer waist of the end wall. The annular sealing strip is seamlessly connected to the end wall and side wall. The membrane cover extends to the annular sealing strip on all four sides and is tightly connected to the annular sealing strip in an airtight manner. This allows the membrane cover to be fully sealed to the end wall and side wall of the trough furnace body through the annular sealing strip, forming a fully sealed smelting production condition for the fixed silicon carbide smelting furnace. This prevents the explosion hazard caused by external air entering the trough furnace body. The exhaust gas generated during smelting is collected into the exhaust gas main pipe through multiple gas inlet pipes extending from the side wall and then transported to the downstream processing stage by a blower.

[0037] Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 , Figure 8 and Figure 9 The diagram shown is an overall structural schematic of an embodiment of a fully enclosed, stationary silicon carbide smelting furnace with exhaust gas recovery according to this utility model. Please refer to [link / reference]. Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 , Figure 8 and Figure 9 The specific implementation principle is as follows;

[0038] Please refer to Figure 1The device is based on the traditional fixed type silicon carbide smelting furnace, two groups of detachable air-permeable side walls 2 are improved into fixed type side walls 2, and the two fixed end walls 1 respectively inlaid with positive and negative electrodes 9 are improved into two groups of fixed side walls 2 and the hearth 3, which are connected into a full-closed type slot furnace body 10 with an open top, the slot furnace body 10 can be built into an above-ground, semi-underground or fully-underground type, and the end walls 1, the side walls 2 and the bottom of the hearth 3 are connected with each other by using air-tight materials. The length and height of the end walls 1 and the side walls 2 of the slot furnace body 10 are determined according to the process parameters of the silicon carbide closed furnace and the charging amount during the full-cycle smelting, and after the slot furnace body 10 is filled with various furnace charges 8 according to the requirements of the silicon carbide smelting process, a film mat 7 is laid on the surface of the slot furnace body 10, and an air-tight film cover 6 is integrally covered on the film mat 7. A closed annular sealing strip 4 is arranged along the length direction of the top of the side wall 2 and the length direction of the waist of the outer side of the end wall 1, the annular sealing strip 4 is seamlessly connected with the end wall 1 and the side wall 2, the film cover 6 extends to the annular sealing strip 4 on four sides, and is tightly connected with the annular sealing strip 4 in an air-tight manner, so that the film cover 6 is fully closed with the end wall 1 and the side wall 2 around the slot furnace body 10 through the annular sealing strip 4, forming a full-closed smelting production condition of the fixed type silicon carbide smelting furnace, so as to prevent the explosion hidden danger caused by the external air entering the slot furnace body 10, and the tail gas generated during smelting is collected through multiple gas guide pipes 24 extending from the side wall 2 into a main tail gas pipe 25, and then is transported to the rear end processing process by using a fan.

[0039] Please refer to Figure 2 , Figure 2 is a cross-sectional type of semi-underground slot furnace body 10, and the two side walls 2, the hearth 3 and the film cover 6 form a closed space filled with furnace charges 8. The side wall 2 is composed of a structure closed layer 21, a pressure regulating cavity layer 22 and an air-permeable dust separation layer 23 from outside to inside. The annular sealing strip 4 and the operation platform 5 are arranged on the top of the side wall 2, the film mat 7 covering the top surface of the slot furnace body 10 filled with furnace charges 8, and the film cover 6 extending to the annular sealing strip 4 on the top surface of the two end side walls 2, wherein the film cover 6 is seamlessly connected with the annular sealing strip 4. Multiple gas guide pipes 24 are arranged along the length direction of the structure closed layer 21, and the gas guide pipes 24 are communicated with the pressure regulating cavity layer 22. The air-permeable dust separation layer 23 uniformly penetrates the tail gas overflowing from the furnace charges 8 into the pressure regulating cavity layer 22, and the multiple gas guide pipes 24 introduce the tail gas collected from the pressure regulating cavity layer 22 into the main tail gas pipe 25 outside the structure closed layer 21.

[0040] Please refer to Figure 3 , Figure 3A kind of section type for end wall 1 of slot furnace body 10, end wall 1 in the figure is composed of end wall insulation layer 11, end wall structural layer 12, end wall refractory layer 13, positive and negative electrodes 9 are inlaid in end wall 1.End wall structural layer 12 can withstand the lateral pressure of the material in the furnace, end wall 1 insulates the space inside and outside the furnace, annular sealing band 4 and operation platform 5 are arranged along the length direction of the waist of the outside of end wall 1, annular sealing band 4 is arranged in the upper area of the positive and negative electrodes 9 inlaid in end wall 1, and is seamlessly connected with the annular sealing band 4 on the side wall 2 of both ends, end wall 1 can also be entirely built with refractory bricks, or the steel reinforced concrete column and base plate that can resist the pressure of furnace charge 8 are inlaid in refractory bricks.End wall 1 and side wall 2, hearth 3 are seamlessly connected, the top surface of end wall 1 can be set as double slope or isosceles trapezoidal type according to the angle of repose of furnace charge 8, the slope surface can be set with steps, facilitating up and down operation.The external corner of end wall 1 and membrane pad 7, membrane cover 6 contact is treated as inverted garden angle, to protect membrane pad 7 and membrane cover 6.Membrane pad 7, membrane cover 6 covering the top surface of slot furnace body 10 filled with furnace charge 8 extend to annular sealing band 4 of the top surface and the outside of end wall 1, wherein membrane cover 6 is seamlessly connected with annular sealing band 4.

[0041] Please refer to Figure 4 , Figure 4 A kind of sealing type for annular sealing band 4 of side wall 2 and membrane cover 6, annular sealing band 4 is set as slot shape in the figure, the annular sealing band 4 of end wall 1 area is also set as slot shape, the slot-shaped sealing bands of two end walls 1 and two side walls 2 are connected with each other, forming a horizontal annular slot-shaped sealing band around the slot furnace body 10, water is filled in the slot.Membrane cover 6 covering the top surface of slot furnace body 10 filled with furnace charge 8 extends to water in the slot-shaped sealing band, to form the sealing of membrane cover 6 by water.In order to prevent membrane cover 6 from being pulled out of water, movable pressing bag 61 is intermittently arranged on membrane cover 6 along the periphery of slot-shaped sealing band.The bottom end of slot-shaped sealing band is provided with drain pipe 41.Membrane pad 7 is lap joint connected and arranged above the material surface, to protect membrane cover 6.

[0042] Please refer to Figure 5 , Figure 5 A kind of sealing type for annular sealing band 4 of side wall 2 and membrane cover 6, annular sealing band 4 is set as U-shaped slot in the figure and Figure 4Similarly, the film cover 6 covering the top surface of the hearth 8 of the slot furnace 10 extends to the U-shaped sealing groove and tightly contacts the U-shaped groove, and then water is added into the film cover 6 in the U-shaped groove to tightly connect the U-shaped groove and the film cover 6 by water pressure, so as to form the sealing of the U-shaped groove to the film cover 6. The film mat 7 is laid on the material surface as a whole to protect the film cover 6. If the ring-shaped sealing band 4 attached to the local area of the end wall 1 is higher than the ring-shaped sealing band 4 of the side wall 2 due to the high setting of the electrode 9, and the water sealing condition is not met, the inflatable rubber band can be used to replace the water sealing film cover 6 in the U-shaped groove, the rubber band is inflated and expanded to press the film cover 6 in the U-shaped groove, so as to form the sealing of the U-shaped groove to the film cover 6.

[0043] Please refer to Figure 6 , Figure 6 A combined type of the side wall 2 is shown in the figure, in which the side wall 2 is composed of a structure sealing layer 21, a pressure regulating cavity layer 22 and a gas permeable dust separation layer 23 from outside to inside. The structure sealing layer 21 is arranged with an air guide pipe 24, the air guide pipe 24 is communicated with the pressure regulating cavity layer 22, and the gas permeable dust separation layer 23 is built with porous bricks. Since the hole diameter of the porous bricks is relatively large, the dust in the tail gas is easy to enter the pressure regulating cavity layer 22 and the air guide pipe 24, and a gas permeable layer 27 is needed to be clamped between the two layers of porous brick walls to play a dust separation role. When the porous bricks are built, the holes of the porous bricks are horizontally arranged, and the tail gas is introduced into the pressure regulating cavity layer 22 through the holes of the porous bricks and the gas permeable layer 27. In order to transmit the material pressure in the furnace to the structure sealing layer 21, the gas permeable dust separation layer 23 is extended out of the bricks in the horizontal and vertical directions, and the top of the gas permeable dust separation layer 23 is supported on the inner wall of the structure sealing layer 21 in the pressure regulating cavity layer 22, so as to protect the structural stability of the gas permeable dust separation layer 23.

[0044] Please refer to Figure 7 , Figure 7 A combined type of the side wall 2 is shown in the figure, in which the side wall 2 is composed of a structure sealing layer 21, a pressure regulating cavity layer 22 and a gas permeable dust separation layer 23 from outside to inside. The structure sealing layer 21 is arranged with an air guide pipe 24, the air guide pipe 24 is communicated with the pressure regulating cavity layer 22, and the gas permeable dust separation layer 23 is built with porous bricks. Since the hole diameter of the porous bricks is relatively large, the dust in the tail gas is easy to enter the pressure regulating cavity layer 22 and the air guide pipe 24, and a gas permeable layer 27 is needed to be clamped between the two layers of porous brick walls to play a dust separation role. When the porous bricks are built, the holes of the porous bricks are horizontally arranged, and the tail gas is introduced into the pressure regulating cavity layer 22 through the holes of the porous bricks and the gas permeable layer 27. In order to transmit the material pressure in the furnace to the structure sealing layer 21, the gas permeable dust separation layer 23 is extended out of the bricks in the horizontal and vertical directions, and the top of the gas permeable dust separation layer 23 is supported on the inner wall of the structure sealing layer 21 in the pressure regulating cavity layer 22, so as to protect the structural stability of the gas permeable dust separation layer 23.

[0045] Please refer to Figure 8 and Figure 9, considering the operation requirements of the silicon carbide furnace matched with the furnace discharge machine and other equipment, a furnace door 26 is needed to be opened at the side wall 2 to facilitate the in-out of the furnace discharge machine and other equipment 264, the width of the furnace door 26 and the height of the door bottom are determined according to the outer shape size of the furnace discharge machine and other equipment 264, and the upper opening of the furnace door 26 is a U-shaped horn open type. The furnace door 26 is installed in an integral hoisting mode, the door frame 265 is embedded on the side wall, the door frame 265 is provided with a plurality of door frame sealing bands 262 corresponding to a plurality of furnace door sealing bands 261 on the door body, the two end faces of the groove-shaped sealing band on the door body are provided with rubber sealing bands corresponding to the rubber sealing bands provided on the end faces of the groove-shaped sealing band on the door frame, after the furnace door 26 is hoisted and reset, the door body and the side wall 2 are pressed and sealed by the locking nut 263 at the top, the groove-shaped sealing band on the door body and the groove-shaped sealing band on the top surface of the side wall 2 are in closed communication, and the furnace door 26 can be made of steel and the contact surface with the furnace charge is inlaid with refractory bricks for heat insulation and insulation treatment.

[0046] Although the utility model has been described above with reference to the embodiments, various improvements can be made and equivalent parts can be replaced without departing from the scope of the utility model. In particular, as long as there is no structural conflict, the features in the embodiments disclosed by the utility model can be combined in any way, and the combinations are not exhaustively described in the specification only for the consideration of omitting the length and saving resources. Therefore, the utility model is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

[0047] Without departing from the scope of the utility model, according to the requirements of the coal gas and other related safety and use specifications, the nitrogen protection, nitrogen replacement, valve group, control valve, explosion-proof valve, safety and detection instrument, water seal, drain trap, diffuser pipe, alarm device, gas online analysis, expansion joint, expansion joint and other facilities configured in the implementation process of the utility model belong to the conventional configuration, which does not exist structural conflict with the utility model, and does not exceed the protection scope of the utility model due to the above configuration.

Claims

1. A totally closed off tail gas recovery stationary type silicon carbide smelting furnace comprising an end wall (1), a side wall (2) and a hearth (3), characterized in that, The end wall (1) is inlaid with electrodes (9), and the end wall (1) inlaid with electrodes (9) and the fixed side wall (2) and hearth (3) are connected to form a full-closed open-top channel furnace body (10); The channel furnace body (10) is filled with furnace charge (8), and a film pad (7) is laid on the charge surface of the furnace charge (8), the film pad (7) is entirely covered with an air-tight film cover (6), a closed annular sealing band (4) is arranged along the length direction of the top of the side wall (2) and the length direction of the waist of the end wall (1), the annular sealing band (4) is seamlessly connected with the end wall (1) and the side wall (2), the film cover (6) extends to the annular sealing band (4) on four sides and is air-tightly and tightly connected with the annular sealing band (4), and the film cover (6) is full-closedly connected with the end wall (1) and the side wall (2) around the channel furnace body (10) through the annular sealing band (4). A plurality of air guide pipes (24) are arranged along the side wall (2), and the ends of the plurality of air guide pipes (24) are communicated with a tail gas main pipe (25).

2. The totally closed off off-gas recovery stationary type SiC smelting furnace according to claim 1, characterized in that, The side wall (2) is composed of a structure sealing layer (21), a pressure regulating cavity layer (22) and an air-permeable dust separation layer (23) from outside to inside, and an operation platform (5) is arranged on the top of the structure sealing layer (21).

3. The totally-closed off exhaust gas recovery stationary-type SiC smelting furnace according to claim 2, characterized by, The air guide pipes (24) are communicated with the pressure regulating cavity layer (22), the air-permeable dust separation layer (23) allows the tail gas overflowing from the furnace charge (8) to permeate into the pressure regulating cavity layer (22), and the plurality of air guide pipes (24) guide the tail gas collected from the pressure regulating cavity layer (22) into the tail gas main pipe (25) outside the structure sealing layer (21).

4. The totally-closed off-gas recovery stationary-type SiC smelting furnace according to claim 3, characterized in that, The end wall (1) is composed of an end wall heat preservation layer (11), an end wall structure layer (12) and an end wall refractory layer (13), and the end wall (1) separates the inner space of the channel furnace body (10) from the outer space.

5. The totally-closed off-gas recovery stationary-type SiC smelting furnace according to claim 4, characterized in that, The end wall (1) includes but is not limited to refractory brick masonry, or inlaid with reinforced concrete columns and base plates in the refractory bricks to resist the pressure of the furnace charge (8).

6. The totally-closed off exhaust gas recovery stationary-type SiC smelting furnace according to claim 5, characterized by: The top surface of the end wall (1) is set as a double slope or isosceles trapezoidal type according to the angle of repose of the furnace charge (8), and the slope surface is provided with steps to facilitate up and down operation, and the external corners of the end wall (1) in contact with the film pad (7) and the film cover (6) are rounded to protect the film pad (7) and the film cover (6).

7. The fixed type SiC smelting furnace of claim 6, wherein: The annular sealing band (4) is arranged in a groove shape on the top of the side wall (2), and the annular sealing band (4) in the waist region of the end wall (1) is also arranged in a groove shape, the groove-shaped sealing bands of the two end walls (1) and the two side walls (2) are connected with each other to form a horizontal annular groove-shaped sealing band around the channel furnace body (10), water is filled in the groove-shaped sealing band, and the film cover (6) extends to the water in the groove-shaped sealing band to form water sealing of the film cover (6).

8. The totally-closed off exhaust gas recovery stationary-type SiC smelting furnace according to claim 7, characterized by: A movable pressing bag (61) is intermittently arranged on the film cover (6) along the groove-shaped sealing band to prevent the film cover (6) from being pulled out of the water, and a drain pipe (41) is arranged at the bottom end of the groove-shaped sealing band.

9. A totally-closed off-gas recovery stationary-type SiC smelting furnace according to claim 8, characterized in that: The film pad (7) is connected in lap joint, and the film pad (7) is arranged on the charge surface of the furnace charge (8) to protect the film cover (6); The air-permeable dust prevention layer (23) includes but is not limited to the air-permeable brickwork, the air-permeable brickwork or the water-permeable brickwork, if the air-permeable brickwork is used, the air-permeable layer (27) is inserted between two layers of the air-permeable brickwork to prevent the dust from entering the pressure regulating cavity layer (22), the holes of the air-permeable brickwork are horizontally arranged, and the tail gas is introduced into the pressure regulating cavity layer (22) through the holes and the air-permeable layer (27).

10. The totally-closed off-gas recovery stationary-type SiC smelting furnace according to claim 9, characterized in that: The side wall (2) is provided with a furnace door (26), and a door frame (265) is pre-buried in the position of the side wall (2). The furnace door (26) is provided with a furnace door sealing strip (261). The door frame (265) is provided with a door frame sealing strip (262). The door body in the position of the furnace door (26) is provided with a furnace door groove-shaped sealing strip (266). The furnace door (26) is provided with an ejection machine (264), and the door body in the position of the furnace door (26) is locked and sealed with the side wall (2) through a locking nut (263).

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