A high efficiency waste gas combustion furnace device

Abstract

The present invention discloses a high-efficiency waste gas combustion furnace device, which belongs to the technical field of combustion furnace devices. A high-efficiency waste gas combustion furnace device comprises an outer shell, the top and bottom ends of the outer shell are respectively connected to an upper cone and a lower cone, the top end of the upper cone is connected to an air intake pipe, the inner part of the outer shell is installed with an internal upper shell body and an internal lower shell body connected up and down, a cleaning component is installed inside the internal upper shell body, and a retention component is installed inside the internal upper shell body. The present invention prolongs the residence time in the combustion furnace, ensures its full combustion, improves the combustion efficiency, and at the same time uses the cleaning component to clean the solid impurities such as coal ash formed by the combustion inside the internal upper shell body, ensures the normal use of the internal structure of the internal upper shell body, so as to improve the combustion efficiency, and at the same time, the heat-insulating cavity can be used to recycle the waste heat.

Description

Technical Field

[0001] The invention relates to the technical field of combustion furnace devices, and in particular to a high-efficiency waste gas combustion furnace device. Background Art

[0002] In the field of waste heat recovery of combustible exhaust gas in industries such as fertilizers and chemicals, a frequently used equipment is the exhaust gas combustion furnace device, which is usually divided into "direct combustion type" and "heat storage type". The two types of exhaust gas combustion furnaces have different functions. The "direct combustion type" exhaust gas combustion furnace refers to an exhaust gas combustion furnace that only burns the exhaust gas and does not recover the heat. The "heat storage type" exhaust gas combustion furnace is an exhaust gas combustion furnace that not only burns the exhaust gas but also recovers the heat.

[0003] However, it still has many shortcomings in actual use, such as the unreasonable arrangement of the burner in the combustion furnace currently used, and the arrangement of the heat storage bricks in the heat storage layer in the furnace adopts the Siemens checker brick type. After the combustible waste gas enters the furnace through the burner nozzle, it stays in the furnace for a short time, the mixing is uneven, and the combustion is not complete. To this end, we proposed a high-efficiency waste gas combustion furnace device to solve the above problems. Summary of the invention

[0004] In order to overcome the above defects of the prior art, the present invention provides a high-efficiency waste gas combustion furnace device to solve the problems raised in the above background technology.

[0005] In order to achieve the above-mentioned purpose, the present invention adopts the following technical scheme: a high-efficiency waste gas combustion furnace device, comprising an outer shell, the top and bottom ends of the outer shell are respectively connected to an upper cone and a lower cone, the top end of the upper cone is connected to an air intake pipe, the upper cone is provided with an upper cone cavity inside, the lower cone is provided with a lower cone cavity inside, an inner upper shell and an inner lower shell connected up and down are installed inside the outer shell, a high calorific value burner is installed on one side of the outer shell, a low calorific value burner is installed on the other side of the outer shell, an ash discharge port is installed on one end of the inner lower shell, a cleaning component is installed inside the inner upper shell, and a retention component is installed inside the inner upper shell;

[0006] The cleaning component includes turbines installed in the middle of the top wall and the middle of the bottom wall of the internal upper shell, a connecting shaft is connected between the two turbines, and the outer sleeve of the connecting shaft is provided with a plurality of groups of connecting plates, each group of connecting plates is divided into an upper and an lower connecting plate, the two side walls of the upper connecting plate are connected to the first cleaning plate, and the two side walls of the lower connecting plate are connected to the second cleaning plate.

[0007] In a preferred embodiment, a first opening is formed on a side of the outer shell close to the high calorific value burner, and an end of the high calorific value burner passes through the first opening and extends to the interior of the upper end of the inner upper shell. A second opening is formed on a side of the outer shell close to the low calorific value burner, and an end of the low calorific value burner passes through the second opening and extends to the interior of the upper end of the inner upper shell. The high calorific value burner and the low calorific value burner are respectively located on both sides of the outer shell.

[0008] In a preferred embodiment, a sealed heat-insulating cavity is formed between the outer shell and the inner upper shell, and the top and bottom ends of the heat-insulating cavity are both connected to a guide tube.

[0009] In a preferred embodiment, a connection port is provided on one side wall of the outer shell, and the structure of the connection port is adapted to the structure of the ash discharge port, when one end of the ash discharge port passes through the connection port and is connected to the inner lower shell.

[0010] In a preferred embodiment, the retention assembly includes a first folding retention plate and a second folding retention plate arranged up and down, the first folding retention plate is arranged obliquely inside the internal upper shell, the upper surface of the first folding retention plate is provided with a plurality of T-shaped retention grooves, and the lower surface of the first folding retention plate is provided with a plurality of arc-shaped retention grooves.

[0011] In a preferred embodiment, the first folding retention plate and the second folding retention plate are arranged in at least one group, each group of the first folding retention plates is arranged in at least two, and the two first folding retention plates are arranged symmetrically, each group of the second folding retention plates is arranged in at least two, and the two second folding retention plates are arranged symmetrically, and each group of the first folding retention plates and each group of the second folding retention plates are vertically arranged on the same vertical plane.

[0012] In a preferred embodiment, the number of the cleaning components is set to twice the number of groups of the first folding retention plates and the second folding retention plates, and a group of cleaning components is installed outside each group of first folding retention plates and each group of second folding retention plates.

[0013] In a preferred embodiment, the first cleaning plate of the cleaning assembly is arranged in parallel with the first folding retention plate, and a T-shaped cleaning block is connected to the position of the lower surface of the first cleaning plate corresponding to the T-shaped retention groove, and the T-shaped cleaning block structure is adapted to the structure of the T-shaped retention groove.

[0014] In a preferred embodiment, the first cleaning plate of the cleaning assembly is arranged in parallel with the second folding retention plate, a circular cleaning block is connected to the upper surface of the first cleaning plate at the position corresponding to the arc retention groove, the circular cleaning block structure is adapted to the structure of the arc retention groove, and the upper surface of the second cleaning plate is provided with guide grooves at the positions on both sides of the circular cleaning block.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] 1. Compared with the prior art, the overall structure designed by the present invention can fully mix high calorific value exhaust gas and low calorific value exhaust gas inside the internal upper shell, and use the retention component to realize the gas reversal and remixing, so that it can be fully mixed and evenly mixed, and at the same time extend its residence time in the combustion furnace to ensure its full combustion and improve combustion efficiency. At the same time, the cleaning component is used to clean the solid impurities such as coal ash formed by the combustion inside the internal upper shell to ensure the normal use of the internal structure of the internal upper shell, so as to improve the combustion efficiency. At the same time, the heat-insulating cavity can be used to recycle the waste heat.

[0017] 2. By setting up a retention component, compared with the prior art, the mixed gas forms two vortices on the surfaces of the first bend retention plate and the second bend retention plate, and the T-shaped retention groove and the arc retention groove are used to further enhance the residence time of the mixed gas on the surfaces of the first bend retention plate and the second bend retention plate. Under the triple effect, the residence time of the mixed gas on the surfaces of the first bend retention plate and the second bend retention plate is greatly increased, so that the reaction degree of the mixed gas is higher and the reaction is more sufficient, and at the same time, the mixing degree of the mixed gas is further improved.

[0018] 3. By setting up a cleaning component, compared with the prior art, there is no need for an external power mechanism. The flow of gas is used to rotate the cleaning component, and the rotating cleaning component is used to stir the three gases, so that the mixed gas is more mixed. At the same time, the cleaning component is used to clean the surface of the retention component, so that the mechanism of the retention component can function normally, thereby indirectly improving the reaction efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of the overall structure of a high-efficiency waste gas combustion furnace device proposed by the present invention.

[0020] Figure 2 This is a schematic structural diagram of a high-efficiency waste gas combustion furnace device proposed by the present invention with the outer shell removed.

[0021] Figure 3 This is a schematic structural diagram of the outer shell proposed by the present invention.

[0022] Figure 4Internal sectional view of the internal upper shell proposed by the present invention

[0023] Figure 5 This is a partial structural schematic diagram of a high-efficiency waste gas combustion furnace device proposed by the present invention.

[0024] Figure 6 This is a partial structural cross-sectional view of a high-efficiency waste gas combustion furnace device proposed by the present invention.

[0025] Figure 7 For the present invention Figure 6 A is an enlarged view of the structure.

[0026] Figure 8 This is a schematic diagram of the structure of the cleaning component and the retention component proposed in the present invention when they are installed.

[0027] Fig. 9 This is a schematic structural diagram of the connecting plate, the first cleaning plate and the second cleaning plate proposed in the present invention when they are installed.

[0028] In the figure: 1. outer shell; 2. upper cone; 3. lower cone; 4. air inlet pipe; 5. inner upper shell; 6. inner lower shell; 7. high calorific value burner; 8. low calorific value burner; 9. ash discharge port; 10. connecting port; 11. first through port; 12. second through port; 13. first folding retention plate; 14. second folding retention plate; 15. heat insulation cavity; 16. upper cone cavity; 17. lower cone cavity; 18. connecting shaft; 19. turbine; 20. connecting plate; 21. first cleaning plate; 22. T-shaped cleaning block; 23. second cleaning plate; 24. circular cleaning block; 25. guide groove; 26. T-shaped retention groove; 27. arc retention groove. DETAILED DESCRIPTION

[0029] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0030] Example 1

[0031] As attached Figure 1-9The high-efficiency waste gas combustion furnace device shown comprises an outer shell 1, the top and bottom ends of the outer shell 1 are respectively connected to an upper cone 2 and a lower cone 3, the top end of the upper cone 2 is connected to an air inlet pipe 4, the upper cone 2 is provided with an upper cone cavity 16, the lower cone 3 is provided with a lower cone cavity 17, the outer shell 1 is provided with an upper shell 5 and an inner lower shell 6 connected up and down, a high calorific value burner 7 is installed on one side of the outer shell 1, a low calorific value burner 8 is installed on the other side of the outer shell 1, an ash discharge port 9 is installed on one end of the inner lower shell 6, a cleaning component is installed in the inner upper shell 5, and a retention component is installed in the inner upper shell 5, the combustible gas enters the upper cone 2 through the air inlet pipe 4, and the cleaning component is driven to rotate by the flow of the combustible gas, so as to clean the retention component, and the retention component decelerates the combustible gas in the inner upper shell 5, so that the residence time is longer, and further makes the reaction more sufficient;

[0032] The cleaning component includes a turbine 19 installed in the middle of the top wall and the middle of the bottom wall of the internal upper shell 5, a connecting shaft 18 is connected between the two turbines 19, and a plurality of groups of connecting plates 20 are sleeved on the outside of the connecting shaft 18. Each group of connecting plates 20 is divided into two upper and lower connecting plates 20. The two side walls of the upper connecting plate 20 are connected to the first cleaning plate 21, and the two side walls of the lower connecting plate 20 are connected to the second cleaning plate 23. When the combustible gas enters the internal upper shell 5 from the upper cone 2, the turbine 19 drives the connecting shaft 18 to rotate, so that the connecting shaft 18 drives the first cleaning plate 21 and the second cleaning plate 23 to rotate through the connecting plate 20, thereby achieving a cleaning effect.

[0033] Specifically, a first opening 11 is provided on one side of the outer shell 1 close to the high calorific value burner 7, and an end of the high calorific value burner 7 passes through the first opening 11 and extends to the interior of the upper end of the inner upper shell 5. A second opening 12 is provided on one side of the outer shell 1 close to the low calorific value burner 8, and an end of the low calorific value burner 8 passes through the second opening 12 and extends to the interior of the upper end of the inner upper shell 5. The high calorific value burner 7 and the low calorific value burner 8 are respectively located on both sides of the outer shell 1. High calorific value combustible exhaust gas is transported to the interior of the inner upper shell 5 through the high calorific value burner 7, and low calorific value combustible exhaust gas is transported to the interior of the inner upper shell 5 through the low calorific value burner 8, and is mixed with the combustible gas transported from the upper cone 2 inside the inner upper shell 5, so that the combustion effect is better and the combustion is more complete.

[0034] Furthermore, a sealed insulating cavity 15 is formed between the outer shell 1 and the inner upper shell 5. The top and bottom ends of the insulating cavity 15 are interconnected with a guide tube. The guide tube is a prior art, i.e., a steel tube with a valve. The insulating cavity 15 is used for insulation, and the high heat conducted from the inner upper shell 5 is transported to the outside through the guide tube, thereby keeping the outer shell 1 at a lower temperature and reducing accidents caused by high temperature.

[0035] It is worth mentioning that a connecting port 10 is provided on one side wall of the outer shell 1, and the structure of the connecting port 10 is compatible with the structure of the ash discharge port 9. When one end of the ash discharge port 9 passes through the connecting port 10 and is connected to the internal lower shell 6, the ash discharge port 9 is supported by the connecting port 10. When the combustible gas, high calorific value combustible gas and low calorific value combustible gas are fully reacted inside the internal upper shell 5, they will flow into the internal lower shell 6, and the generated flue gas, coal ash and other solid impurities will also accumulate inside the internal lower shell 6. Through the connecting port 10, a valve is provided on the surface of the connecting port 10, which can remove the solid impurities inside the internal lower shell 6.

[0036] It is worth noting that the retention assembly includes a first folding retention plate 13 and a second folding retention plate 14 arranged up and down. The first folding retention plate 13 is arranged obliquely inside the internal upper shell 5. The upper surface of the first folding retention plate 13 is provided with a plurality of T-shaped retention grooves 26, and the lower surface of the first folding retention plate 13 is provided with a plurality of arc-shaped retention grooves 27. When the combustible gas, the high calorific value combustible gas and the low calorific value combustible gas are mixed into a mixed gas inside the internal upper shell 5, they will continue to be transported downward. However, during the transportation process, the mixed gas hits the first folding retention plate 13. The mixed gas flows toward the surface of the first deflection retention plate 13 and the second deflection retention plate 14, thereby being blocked and colliding with the transported gas to form convection, thereby generating a vortex phenomenon, causing the mixed gas to stay longer on the surface of the first deflection retention plate 13 and the second deflection retention plate 14, thereby lengthening the residence time of the mixed gas inside the internal upper shell 5, and the reaction is more complete, and the mixed gas forming the vortex will further stay in the T-shaped retention groove 26 and the arc-shaped retention groove 27, resulting in a further increase in the residence time of the mixed gas, more complete combustion, and better combustion effect.

[0037] In addition, the first folding retention plate 13 and the second folding retention plate 14 are arranged in at least one group, each group of the first folding retention plates 13 is arranged in at least two, the two first folding retention plates 13 are symmetrically arranged, each group of the second folding retention plates 14 is arranged in at least two, the two second folding retention plates 14 are symmetrically arranged, each group of the first folding retention plates 13 and each group of the second folding retention plates 14 are vertically arranged on the same vertical plane, when the mixed gas hits the surface of the first folding retention plate 13, a vortex will be formed on the surface of the first folding retention plate 13, and a part of the gas in the vortex will enter the surface of the second folding retention plate 14 along the gap between the two first folding retention plates 13, and the mixed gas can further form a vortex on the surface of the second folding retention plate 14 through the cross-arranged first folding retention plates 13 and the second folding retention plates 14, thereby greatly increasing the retention time of the mixed gas in the internal upper shell 5.

[0038] It must be said that the number of cleaning components is set to twice the number of groups of the first folding retention plates 13 and the second folding retention plates 14, and a group of cleaning components is installed on the outside of each group of first folding retention plates 13 and each group of second folding retention plates 14, and the cleaning components are used to clean the upper and lower surfaces of the first folding retention plates 13 and the second folding retention plates 14.

[0039] Furthermore, the first cleaning plate 21 of the cleaning assembly is arranged in parallel with the first folding retention plate 13, and a T-shaped cleaning block 22 is connected to the position of the lower surface of the first cleaning plate 21 corresponding to the T-shaped retention groove 26. The structure of the T-shaped cleaning block 22 is adapted to the structure of the T-shaped retention groove 26. When the connecting shaft 18 rotates, the first cleaning plate 21 also rotates therewith, so that the T-shaped cleaning block 22 slides inside the T-shaped retention groove 26, and then the T-shaped cleaning block 22 cleans the inside of the T-shaped retention groove 26, cleans the solid impurities such as coal ash generated by the mixed gas reaction, and the cleaned impurities fall downward and finally fall into the internal lower shell 6.

[0040] It must be said that the first cleaning plate 21 of the cleaning assembly is arranged in parallel with the second folding retention plate 14, and a circular cleaning block 24 is connected to the position of the arc retention groove 27 on the upper surface of the first cleaning plate 21, and the structure of the circular cleaning block 24 is adapted to the structure of the arc retention groove 27. The upper surface of the second cleaning plate 23 is provided with guide grooves 25 at the positions on both sides of the circular cleaning block 24. When the connecting shaft 18 rotates, the first cleaning plate 21 also rotates therewith, so that the circular cleaning block 24 slides inside the arc retention groove 27, and then the circular cleaning block 24 cleans the inside of the arc retention groove 27, and cleans the solid impurities such as coal ash generated by the mixed gas reaction. The cleaned impurities fall downward and slide into the guide groove 25, and slide to the bottom of the internal upper shell 5 through the guide groove 25, but finally fall into the internal lower shell 6.

[0041] Working principle of the present invention: refer to the attached manual Figure 1-9 , a combustible gas such as hydrogen is introduced into the upper cone 2 through the air inlet pipe 4, and the hydrogen in the upper cone 2 moves into the inner upper shell 5 and drives the turbine 19 to rotate, thereby causing the cleaning component to rotate. When the hydrogen enters the inner upper shell 5, the high calorific value combustible gas is delivered from the high calorific value burner 7, and the low calorific value combustible gas is delivered from the low calorific value burner 8, so that the three gases are mixed into a mixed gas and a combustion reaction is carried out in the inner upper shell 5;

[0042] The mixed gas flows downward in the internal upper shell 5 and hits the retention component. The mixed gas is first blocked by the first bend retention plate 13, thereby forming a vortex on the surface of the first bend retention plate 13, prolonging the residence time of the mixed gas inside the internal upper shell 5, thereby improving the reaction effect. Thereafter, the gas flowing out of the first bend retention plate 13 continues to hit the second bend retention plate 14, thereby forming another vortex, further prolonging the residence time of the mixed gas inside the internal upper shell 5, and improving the reaction effect for the second time. In addition, the T-shaped retention grooves 26 and arc-shaped retention grooves 27 provided on the upper and lower surfaces of the first bend retention plate 13 can further increase the residence time of the vortex-shaped mixed gas on the surface of the first bend retention plate 13, and improve the reaction effect for the third time. With the three-pronged approach, the reaction effect is greatly improved, thereby enhancing the reaction efficiency and achieving the effect of efficient combustion of exhaust gas. The working state of the second bend retention plate 14 is the same as that of the first bend retention plate 13.

[0043] When the connecting shaft 18 in the cleaning component rotates, the first cleaning plate 21 can be driven to rotate on the upper and lower surfaces of the first folding retention plate 13 and the second folding retention plate 14, so that the T-shaped cleaning block 22 matched with the T-shaped retention groove 26 slides in the T-shaped retention groove 26, and then the solid impurities such as coal ash in the T-shaped retention groove 26 are removed. The matched circular cleaning block 24 slides in the arc-shaped retention groove 27 to remove the solid impurities such as coal ash in the arc-shaped retention groove 27, so that the cleaning effect is greatly improved, and no additional power mechanism is required. In addition, the rotating cleaning component further makes the three gases more evenly mixed and the mixing effect is better.

[0044] Finally, a few points should be explained: First, in the description of this application, it should be noted that, unless otherwise specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, which may refer to mechanical connection or electrical connection, or internal communication between two components, or direct connection. "upper", "lower", "left", "right", etc. are only used to indicate relative positional relationships. When the absolute position of the object being described changes, the relative positional relationship may change;

[0045] Secondly: In the drawings of the embodiments disclosed in the present invention, only the structures related to the embodiments disclosed in the present invention are involved, and other structures can refer to the general design. In the absence of conflict, the same embodiment and different embodiments of the present invention can be combined with each other;

[0046] Finally: The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A high-efficiency waste gas combustion furnace device, comprising an outer shell (1), characterized in that: The top and bottom ends of the outer shell (1) are respectively connected to an upper cone (2) and a lower cone (3); the top end of the upper cone (2) is connected to an air intake pipe (4); an upper cone cavity (16) is provided inside the upper cone (2); a lower cone cavity (17) is provided inside the lower cone (3); an upper shell (5) and an lower shell (6) connected up and down are installed inside the outer shell (1); a high calorific value burner (7) is installed on one side of the outer shell (1); a low calorific value burner (8) is installed on the other side of the outer shell (1); an ash discharge port (9) is installed on one end of the inner lower shell (6); a cleaning component is installed inside the inner upper shell (5); and a retention component is installed inside the inner upper shell (5); The retention assembly comprises a first folding retention plate (13) and a second folding retention plate (14) which are arranged in an upper and lower manner, wherein the first folding retention plate (13) is arranged obliquely inside the internal upper shell (5), and a plurality of T-shaped retention grooves (26) are provided on the upper surface of the first folding retention plate (13), and a plurality of arc-shaped retention grooves (27) are provided on the lower surface of the first folding retention plate (13); The cleaning assembly comprises turbines (19) mounted at the middle of the top wall and the middle of the bottom wall of the internal upper shell (5), a connecting shaft (18) being connected between the two turbines (19), a plurality of groups of connecting plates (20) being sleeved on the outside of the connecting shaft (18), each group of connecting plates (20) being divided into two upper and lower connecting plates (20), the two side walls of the upper connecting plate (20) being connected to the first cleaning plates (21), and the two side walls of the lower connecting plate (20) being connected to the second cleaning plates (23); A first opening (11) is provided on a side of the outer shell (1) close to the high calorific value burner (7), and an end of the high calorific value burner (7) passes through the first opening (11) and extends to the interior of the upper end of the inner upper shell (5). A second opening (12) is provided on a side of the outer shell (1) close to the low calorific value burner (8), and an end of the low calorific value burner (8) passes through the second opening (12) and extends to the interior of the upper end of the inner upper shell (5). The high calorific value burner (7) and the low calorific value burner (8) are respectively located on two sides of the outer shell (1).

2. A high-efficiency waste gas combustion furnace device according to claim 1, characterized in that: A sealed heat-insulating cavity (15) is formed between the outer shell (1) and the inner upper shell (5), and the top and bottom ends of the heat-insulating cavity (15) are both communicated and connected with a guide tube.

3. The high-efficiency waste gas combustion furnace device according to claim 1 is characterized in that: A connecting port (10) is provided on one side wall of the outer shell (1), and the structure of the connecting port (10) is compatible with the structure of the ash discharge port (9). When one end of the ash discharge port (9) passes through the connecting port (10) and is connected to the inner lower shell (6), 4. The high-efficiency waste gas combustion furnace device according to claim 1, characterized in that: The first folding retention plate (13) and the second folding retention plate (14) are arranged in at least one group, each group of the first folding retention plates (13) is arranged in at least two, the two first folding retention plates (13) are arranged symmetrically, each group of the second folding retention plates (14) is arranged in at least two, the two second folding retention plates (14) are arranged symmetrically, and each group of the first folding retention plates (13) and each group of the second folding retention plates (14) are arranged vertically on the same vertical plane.

5. The high-efficiency waste gas combustion furnace device according to claim 1, characterized in that: The number of the cleaning components is set to be twice the number of groups of the first folding retention plates (13) and the second folding retention plates (14), and a group of cleaning components is installed outside each group of the first folding retention plates (13) and each group of the second folding retention plates (14).

6. The high-efficiency waste gas combustion furnace device according to claim 1, characterized in that: The first cleaning plate (21) of the cleaning assembly is arranged in parallel with the first folding retention plate (13); a T-shaped cleaning block (22) is connected to the lower surface of the first cleaning plate (21) at a position corresponding to the T-shaped retention groove (26); the structure of the T-shaped cleaning block (22) is compatible with the structure of the T-shaped retention groove (26).

7. The high-efficiency waste gas combustion furnace device according to claim 6, characterized in that: The first cleaning plate (21) of the cleaning assembly is arranged in parallel with the second folding retention plate (14); a circular cleaning block (24) is connected to the upper surface of the first cleaning plate (21) at a position corresponding to the arc-shaped retention groove (27); the structure of the circular cleaning block (24) is compatible with the structure of the arc-shaped retention groove (27); and guide grooves (25) are provided on the upper surface of the second cleaning plate (23) at positions on both sides of the circular cleaning block (24).

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