Fully automatic graphene composite material preparation device

Abstract

The application discloses a full-automatic graphene composite material preparation device, which comprises a feeding device, a pretreater and a reactor, the discharge end of the feeding device is connected with the feeding end of a conveying device, the input end of the pretreater is connected with the output end of the conveying device, the feeding end of the reactor is communicated with the discharge end of another conveying device, the feeding end of the other conveying device is connected with the discharge end of the pretreater, the power ends of the two conveying devices are connected with the power output ends of reducers, the feeding device comprises two feeding pipes and a hopper, the hopper is installed at the feeding end of one feeding pipe, the discharge end of the one feeding pipe is communicated with the feeding end of the other feeding pipe through a tee joint, the discharge end of the other feeding pipe is communicated with the corresponding conveying device, a stepping motor is installed on one side of each feeding pipe, and the output end of the stepping motor is connected with a valve core in the feeding pipe. The application can prepare finished products without additional chemical treatment, has good continuity, and does not generate waste liquid and waste residue in the preparation process.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of composite material preparation, and in particular to a full-automatic graphene composite material preparation device. BACKGROUND

[0002] Graphene is a carbon material with a single-atom two-dimensional honeycomb lattice structure. Due to its ultra-thin, two-dimensional (2D) properties and its unprecedented performance, graphene has become the most popular nanomaterial. Its ultra-high specific surface area (the theoretical calculation of the specific surface area of single-layer graphene is 2620 m / g), excellent electron mobility (200000 cm / (V·s)), high thermal conductivity (thermal conductivity is as high as 5300 W / m·k), ultra-strong mechanical properties and good biocompatibility.

[0003] The existing graphene composite material production process has the following problems:

[0004] 1. Price cost problem. The current industrial production technology for preparing graphene composite materials is a chemical method, which has a high total preparation cost. Due to the high cost, the finished product price is high, which is not conducive to industrial production.

[0005] 2. Environmental problem. The use of chemical methods for preparation can cause environmental pollution, and the generated waste gas (acidic) and waste liquid (acidic) can cause huge waste water and waste gas, which makes the production unable to develop in a way that is conducive to environmental protection.

[0006] 3. Stability problem. Currently, almost 100% of the finished products are prepared by chemical methods, which results in a low yield. If the details are not controlled well during production, the entire reaction batch of products will be unqualified, causing huge production waste. Since the chemical method is not a continuous production process, the use of reaction batches may result in the entire reaction batch being scrapped, and the stability is extremely poor.

[0007] 4. Complex process problem. The chemical production process is complex, which results in poor stability.

[0008] Therefore, the full-automatic graphene composite material preparation device is provided by the person skilled in the art to solve the problems in the above background. SUMMARY

[0009] The present application provides a full-automatic graphene composite material preparation device that does not require additional chemical treatment, has good continuity, and does not produce waste liquid and waste residue during preparation.

[0010] In order to achieve the above-mentioned purpose, the present application provides the following technical solutions:

[0011] The full-automatic graphene composite material preparation device of the application comprises:

[0012] The feeding device is connected with the feeding end of a conveying device;

[0013] The pretreater is connected with the output end of the conveying device;

[0014] The reactor is communicated with the feeding end of another conveying device, and the feeding end of the other conveying device is connected with the output end of the pretreater;

[0015] The power ends of the two conveying devices are connected with the power output end of the speed reducer;

[0016] The feeding device comprises two feeding pipes and a hopper, the hopper is installed at the feeding end of one of the feeding pipes, the output end of one of the feeding pipes is communicated with the feeding end of the other feeding pipe through a tee joint, the output end of the other feeding pipe is communicated with the corresponding conveying device, one side of each of the feeding pipes is installed with a stepping motor, the output end of the stepping motor is connected with a valve core in the feeding pipe, a plurality of grooves are uniformly arranged on the outer periphery of the valve core, the third interface of the tee joint is communicated with a front vacuum pipe, and a filter element is arranged at the connection position of the tee joint and the front vacuum pipe.

[0017] Further, the conveying device comprises a conveying pipe, a screw rod is arranged in the conveying pipe, the screw rod is arranged along the length direction of the conveying pipe, helical blades are arranged on the screw rod, and one end of the screw rod is connected with the output end of the speed reducer.

[0018] Further, a protective gas conveying pipe is arranged on the conveying pipe close to the feeding end, the gas inlet end of the protective gas conveying pipe is communicated with a gas source, and the gas outlet end of the protective gas conveying pipe is communicated with the inner cavity of the conveying pipe.

[0019] Further, a second necking mechanism is arranged in the pretreater, the screw rod extends into the second necking mechanism, and the diameter of one end of the second necking mechanism close to the screw rod is greater than the diameter of the other end of the second necking mechanism.

[0020] Further, the second necking mechanism comprises a second necking body, the two end faces of the second necking body are respectively inwardly recessed to form a first circular hole and a second circular hole, the first circular hole and the second circular hole are communicated, the hole diameters of the connection positions of the first circular hole and the second circular hole are the same, the hole diameter of the first circular hole away from the second circular hole is greater than the hole diameter of the first circular hole close to the second circular hole, the hole diameter of the second circular hole close to the first circular hole is greater than the hole diameter of the second circular hole away from the first circular hole, and the end portion of the second circular hole away from the first circular hole is communicated with the output end of the pretreater.

[0021] Further, a heating pipe is arranged in the second circular hole, the heating pipe is communicated with the first circular hole, and the top end and the bottom end of the heating pipe are connected with electrodes respectively.

[0022] Further, a first necking mechanism is arranged in the reactor, the screw rod extends into the first necking mechanism, and the diameter of the first necking mechanism near one end of the screw rod is larger than the diameter of the other end of the first necking mechanism.

[0023] Further, the first necking mechanism comprises a first necking body, the two end faces of the first necking body are inwardly recessed to form a third circular hole and a fourth circular hole respectively, the third circular hole and the fourth circular hole are communicated, the hole diameter of the connection part of the third circular hole and the fourth circular hole is the same, the hole diameter of the third circular hole away from the fourth circular hole is larger than the hole diameter of the third circular hole close to the fourth circular hole, the hole diameter of the fourth circular hole close to the third circular hole is larger than the hole diameter of the fourth circular hole away from the third circular hole, and the end of the fourth circular hole away from the third circular hole is communicated with the discharge end of the reactor.

[0024] Further, a discharge pipe is arranged in the fourth circular hole, the discharge pipe is communicated with the third circular hole, and the top end and the bottom end of the discharge pipe are connected with electrodes respectively.

[0025] Further, the conveying pipe between the pretreater and the other conveying device is communicated through a pipeline, and the pipeline is communicated with the waste gas vacuum pipe through the gas outlet pipe.

[0026] In the above technical solution, the full-automatic graphene composite material preparation device provided by the application has the following beneficial effects:

[0027] 1. The front vacuum pipe is used to form a vacuum section at the positions of the two feeding pipes and between the two stepping motors, so as to remove air in the powder; the rotary scraper arranged in the tee joint is used to scrape off the powder grinding material on the filter core, so as to ensure the accuracy of the powder grinding material entering the next process. The two feeding pipes are sealingly connected with the two stepping motors and the tee joint.

[0028] 2. The powder grinding material enters the corresponding conveying pipe through the two valve cores, and the powder grinding material enters the extrusion cavity of the conveying pipe under the action of gravity. The inert gas can be sent into the conveying pipe through the protective gas conveying pipe. Due to the existence of the inert gas (protective gas), the extrusion cavity in the conveying pipe forms a certain degree of positive pressure, so that the cavity is always in the protective atmosphere of the protective gas, which can protect the powder grinding material from air pollution.

[0029] 3. The cooperation of the speed reducer and the screw rod can make the powder always advance forward, so that the overall feeding speed and the extrusion speed can be adjusted, thereby accurate matching can be realized. The screw rod drives the rotating blades to push and turn, so that the powder grinding material and the protective gas are fully mixed.

[0030] 4、First necking mechanism and second locking mechanism are for sample to reach a certain degree of extrusion, extrusion density not only relates to the conductivity of the material, but also relates to the degree of micro explosion, the volume is reduced by necking, and a certain extrusion is formed, the power is derived from the screw and the rotating blade conveying, the feeding speed can be controlled by accurately controlling the rotation of the screw, and the proportion of the raw material compression can be accurately controlled by matching the reduction ratio of the necking, so that the stability of preparation can be accurately controlled. BRIEF DESCRIPTION OF DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments described in the present application, and other drawings can also be obtained by those skilled in the art according to these drawings.

[0032] Figure 1 A perspective view of the full-automatic graphene composite material preparation device provided by the embodiment of the present application;

[0033] Figure 2 A front view of Figure 1 ;

[0034] Figure 3 A top view of Figure 1 ;

[0035] Figure 4 A side view of A-A in Figure 2 ;

[0036] Figure 5 A side view of B-B in Figure 2 ;

[0037] Figure 6 A side view of C-C in Figure 2 ;

[0038] Figure 7 A side view of D-D in Figure 3 .

[0039] Explanation of reference signs:

[0040] 10, feeding device; 11, feeding pipe; 12, hopper; 13, tee; 14, stepping motor; 15, valve core; 16, groove; 17, pre-vacuum pipe; 18, filter element;

[0041] 20, conveying device; 21, conveying pipe; 22, screw; 23, helical blade; 24, protective gas conveying pipe;

[0042] 30, pretreater; 31, second necked body; 32, first circular hole; 33, second circular hole; 34, heating tube;

[0043] 40, reactor; 41, first necked body; 42, third circular hole; 43, fourth circular hole; 44, discharge tube;

[0044] 50, speed reducer;

[0045] 60, pipeline; 61, gas outlet pipe; 62, exhaust vacuum pipe. DETAILED DESCRIPTION

[0046] In order to make the technical personnel in the art better understand the technical solutions of the present application, the present application will be further described in detail below in conjunction with the drawings.

[0047] Referring to Figures 1-7 as shown;

[0048] The full-automatic graphene composite material preparation device described in the embodiment of the present application comprises:

[0049] The feeding device 10 is connected with the feeding end of a conveying device 20;

[0050] The pretreater 30 is connected with the output end of the conveying device 20;

[0051] The reactor 40 is communicated with the discharging end of another conveying device 20, and the feeding end of the other conveying device 20 is connected with the discharging end of the pretreater 30;

[0052] The power ends of the two conveying devices 20 are connected with the power output end of the speed reducer 50;

[0053] The feeding device 10 comprises two feeding pipes 11 and a hopper 12, the hopper 12 serving as a storage device for filling raw materials; the hopper 12 is installed at the feeding end of one of the feeding pipes 11, the discharging end of one of the feeding pipes 11 is communicated with the feeding end of the other feeding pipe 11 through a tee joint 13, the discharging end of the other feeding pipe 11 is communicated with the corresponding conveying device 20, one side of each of the feeding pipes 11 is installed with a stepping motor 14, the output end of the stepping motor 14 is connected with a valve core 15 in the feeding pipe 11, the speed of the stepping motor 14 is controlled to realize deoxidization and speed-controllable feeding, a plurality of grooves 16 are uniformly arranged on the outer circumference of the valve core 15, the third interface of the tee joint 13 is communicated with a pre-vacuum pipe 17, and a filter element 18 is arranged at the connection position of the tee joint 13 and the pre-vacuum pipe 17.

[0054] The front vacuum tube 17 is a copper tube and is communicated with a vacuum pump, which is used to form a vacuum section at the position between the two inlet pipes 11 and the two stepping motors 14, so as to remove the air, mainly oxygen, in the powder material; the rotary scraper arranged in the three-way pipe 13 is used to scrape the powder material on the filter core 18, so as to ensure the accuracy of the amount of powder material entering the next process. The two inlet pipes 11 are sealingly connected with the two stepping motors 14 and the three-way pipe 13.

[0055] The six grooves 16 on each valve core 15 can bring a certain amount of powder material, which passes through the vacuum section of the pipe section between the two valve cores 15, so as to achieve the purpose of deoxidizing the powder material.

[0056] During operation, the gas can pass through the filter core 18, while the powder material cannot pass through the filter core 18. Under the condition of long-time operation, the end surface of the filter core 18 close to the vacuum tube 17 will accumulate powder material. The rotary scraper driven by the stepping motor continuously scrapes the end surface of the filter core 18, so as to remove the powder material remaining on the surface. The filter core 18 is a ceramic filter core, which can pass through water molecules and air molecules, but cannot pass through powder material, so that the filtering effect is achieved, and thus the powder material is not taken away.

[0057] The above process is continuous, so as to improve the simplicity and continuity of the preparation process.

[0058] The conveying device 20 comprises a conveying pipe 21, a screw rod 22 is arranged in the conveying pipe 21, the screw rod 22 is arranged along the length direction of the conveying pipe 21, helical blades 23 are arranged on the screw rod 22, and one end of the screw rod 22 is connected with the output end of the corresponding speed reducer 50. A protective gas conveying pipe 24 is arranged on the conveying pipe 21 close to the inlet end, the gas inlet end of the protective gas conveying pipe 24 is communicated with a gas source, and the gas outlet end of the protective gas conveying pipe 24 is communicated with the inner cavity of the conveying pipe 21.

[0059] The powder material enters the corresponding conveying pipe 21 through the two valve cores 15, and the powder material enters the extrusion cavity of the conveying pipe 21 under the action of gravity. The inert gas can be sent into the conveying pipe 21 through the protective gas conveying pipe 24. Due to the existence of the inert gas (protective gas), the extrusion cavity in the conveying pipe 21 forms a certain degree of positive pressure, so that the cavity is always in the protective atmosphere of the protective gas, which can protect the powder material from air pollution.

[0060] The cooperation of the stepping motor 14 and the screw rod 22 can adjust the tightness of the extrusion, that is, the cooperation of the feeding speed and the extrusion speed can control the tightness of the rear end of this part.

[0061] The cooperation of the reducer 50 and the screw 22 can make the powder always move forward. The reducer 50 is controlled in a closed loop to accurately control the amount of the powder reaching the preprocessor 30. The overall feeding speed and the extrusion speed can be adjusted to accurately match and reach the ideal powder pressure to make the powder pass through the preprocessor 30 under the appropriate pressure. The screw 22 drives the rotating blade 12 to push and turn to make the powder and the protective gas fully mix.

[0062] The preprocessor 30 is provided with a second necking mechanism, the screw 22 can extend into the corresponding second necking mechanism, and the diameter of one end of the second necking mechanism close to the screw 22 is greater than the diameter of the other end of the second necking mechanism.

[0063] The second necking mechanism includes a second necking body 31, the two end faces of the second necking body 31 are respectively inwardly recessed to form a first circular hole 32 and a second circular hole 33, the first circular hole 32 and the second circular hole 33 are communicated, the hole diameters of the connection part of the first circular hole 32 and the second circular hole 33 are the same, the hole diameter of the first circular hole 32 away from the second circular hole 33 is greater than the hole diameter of the first circular hole 32 close to the second circular hole 33, the hole diameter of the second circular hole 33 close to the first circular hole 32 is greater than the hole diameter of the second circular hole 33 away from the first circular hole 32, and the end of the second circular hole 33 away from the first circular hole 32 is communicated with the discharge end of the preprocessor 30.

[0064] The second circular hole 33 is provided with a heating pipe 34, the heating pipe 34 is communicated with the first circular hole 32, the top end and the bottom end of the heating pipe 34 are respectively connected with electrodes, the electrode connected with the top end of the heating pipe 34 is a pre-processing anode, and the electrode connected with the bottom end of the heating pipe 34 is a pre-processing cathode.

[0065] The preprocessor 30 is controlled by the controller to apply a positive voltage with a large enough current, and the powder is pre-processed under the action of the current.

[0066] After the powder passes through the preprocessor 30, the temperature of the powder is higher than 120 degrees Celsius due to the heating effect of the preprocessor 30 releasing electric energy, and the moisture and impurities are removed here. The release of electric energy and the interval frequency can be accurately controlled to control this part.

[0067] The reactor 40 is provided with a first necking mechanism, the screw 22 extends into the corresponding first necking mechanism, and the diameter of one end of the first necking mechanism close to the screw is greater than the diameter of the other end of the first necking mechanism.

[0068] The first necking mechanism comprises a first necking body 41, two end faces of the first necking body 41 are respectively inwardly recessed to form a third circular hole 42 and a fourth circular hole 43, the third circular hole 42 and the fourth circular hole 43 are communicated, and the hole diameters at the connecting positions of the third circular hole 42 and the fourth circular hole 43 are the same, the hole diameter of the third circular hole 42 away from the fourth circular hole 43 is larger than the hole diameter of the third circular hole 42 close to the fourth circular hole 43, the hole diameter of the fourth circular hole 43 close to the third circular hole 42 is larger than the hole diameter of the fourth circular hole 43 away from the third circular hole 42, and the end of the fourth circular hole 43 away from the third circular hole 42 is communicated with the discharge end of the reactor 40.

[0069] The fourth circular hole 43 is provided with a discharge tube 44, the discharge tube 44 is communicated with the third circular hole 42, the top end and the bottom end of the discharge tube 44 are respectively connected with electrodes, the electrode connected with the top end of the discharge tube 44 is a reaction anode, and the electrode connected with the bottom end of the discharge tube 44 is a reaction anode.

[0070] The pretreater 30 and the conveying pipe 21 of the other conveying device are communicated through a pipeline 60, the pipeline 60 is communicated with a waste gas vacuum pipe 62 through a gas outlet pipe 61, and a ceramic filter element can be arranged at the connecting position of the waste gas vacuum pipe 62 and the gas outlet pipe 61, so as to avoid that the ground material is discharged through the waste gas vacuum pipe.

[0071] The second necking mechanism extrudes the entering ground material, and the ground material is pretreated under the action of the electrode to remove VOCs. The volatilized VOCs are effectively removed through the pipeline 60, the gas outlet pipe 61 and the waste gas vacuum pipe 62. The ground material enters the next process, that is, the extrusion chamber of the conveying pipe 20 before reaction, under the action of gravity.

[0072] The pipeline 60, the gas outlet pipe 61, the waste gas vacuum pipe 62 and the protective gas conveying pipe 24 on the reactor 20 constitute a secondary vacuum system, which is used for removing water vapor and volatile organic compounds generated in the pretreatment process in the pretreater 30. The ground material is transmitted downward under the action of gravity, and other generated waste gas components are discharged in the negative pressure interval formed here.

[0073] The protective gas is inert gas, so that the water vapor and organic oxides generated in the pretreatment process can be diluted in the pretreatment stage at the beginning of the preparation process, and are carried away by the negative pressure device under the driving of the protective gas. Since the whole process is continuous, the raw materials treated in this way can basically remove the water and other volatile organic compounds.

[0074] The first necking mechanism and the second locking mechanism are used to make the sample reach a certain degree of extrusion, and the extrusion density is related to not only the conductivity of the material, but also the degree of micro-explosion. The volume is reduced by the necking, and a certain extrusion is formed. The power is derived from the conveying of the screw 22 and the rotating blade 23. By accurately controlling the rotation of the screw, the feeding speed can be controlled, and by matching the reduction ratio of the necking, the compression ratio of the raw material can be accurately controlled, so that the stability of the preparation can be accurately controlled.

[0075] The device is controlled by a controller, the controller is provided with a numerical control card, the peripheral interface of the numerical control card is connected with various action components and execution mechanism movements and actions, the control of the power output part is also completed by the control card, in addition, the power component is connected with the power source to obtain output power, and the overall function of the mechanism is controlled by software. The inert gas is provided by a high-pressure gas cylinder to ensure sufficient pressure, and then is divided into multiple paths by a multi-path. The control card is controlled by computer software, and the negative pressure device is also controlled by the computer. That is, the entire production process is accurately controlled, the entire production process is controllable, adjustable and reproducible after the raw material enters the hopper, and the repeatability is high.

[0076] The above only describes some exemplary embodiments of the application by way of illustration, and it is needless to say that those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the application. Therefore, the above drawings and descriptions are illustrative in nature and should not be understood as limiting the scope of protection of the claims of the application.

Claims

1. A fully automated apparatus for the preparation of graphene composites, characterized in that, The utility model relates to a kind of pre-treatment device for preparing graphene oxide, including: Feeding device (10), the discharge end of the feeding device (10) is connected with the feeding end of a conveying device; Preprocessor (30), the input end of the preprocessor (30) is connected with the output end of the conveying device; Reactor (40), the feeding end of the reactor (40) is communicated with the discharge end of another conveying device, and the feeding end of the another conveying device is connected with the discharge end of preprocessor (30); The power end of the two conveying devices is connected with the power output end of the speed reducer (50); The feeding device (10) includes two feeding pipes and hopper (12), the hopper (12) is installed at the feeding end of one of the feeding pipes, the discharge end of the one of the feeding pipes is communicated with the feeding end of another feeding pipe through a tee joint (13), the discharge end of the another feeding pipe is communicated with the corresponding conveying device, one side of each of the feeding pipes is provided with a stepper motor (14), the output end of the stepper motor (14) is connected with a valve core (15) in the feeding pipe, a plurality of grooves (16) are uniformly arranged on the outer circumference of the valve core (15), the third interface of the tee joint (13) is communicated with a pre-vacuum pipe (17), and a filter element (18) is arranged at the connection position of the tee joint (13) and the pre-vacuum pipe (17); The conveying device includes a conveying pipe, and a screw rod is arranged in the conveying pipe and arranged along the length direction of the conveying pipe; The preprocessor (30) is provided with a second necking mechanism, and the screw rod in the conveying device connected with the input end of the preprocessor (30) can extend into the corresponding second necking mechanism, and the diameter of one end of the second necking mechanism close to the screw rod is greater than the diameter of the other end of the second necking mechanism; The second necking mechanism includes a second necking body (31), and the two end faces of the second necking body (31) are respectively inwardly recessed to form a first circular tapered hole (32) and a second circular tapered hole (33), the first circular tapered hole (32) and the second circular tapered hole (33) are communicated, and the hole diameter of the connection position of the first circular tapered hole (32) and the second circular tapered hole (33) is the same, the hole diameter of the first circular tapered hole (32) away from the second circular tapered hole (33) is greater than the hole diameter of the first circular tapered hole (32) close to the second circular tapered hole (33), the hole diameter of the second circular tapered hole (33) close to the first circular tapered hole (32) is greater than the hole diameter of the second circular tapered hole (33) away from the first circular tapered hole (32), and the end of the second circular tapered hole (33) away from the first circular tapered hole (32) is communicated with the discharge end of the preprocessor (30); A heating pipe (34) is arranged in the second circular tapered hole (33), the heating pipe (34) is communicated with the first circular tapered hole (32), and the top end and the bottom end of the heating pipe (34) are respectively connected with electrodes; The reactor (40) is provided with a first necking mechanism, and the screw rod in the conveying device communicated with the feeding end of the reactor extends into the corresponding first necking mechanism, and the diameter of one end of the first necking mechanism close to the screw rod is greater than the diameter of the other end of the first necking mechanism. The first necking mechanism comprises a first necking body (41), two end faces of the first necking body (41) are respectively inwardly recessed to form a third circular tapered hole (42) and a fourth circular tapered hole (43), the third circular tapered hole (42) and the fourth circular tapered hole (43) are communicated, and the diameters of the third circular tapered hole (42) and the fourth circular tapered hole (43) at the connection position are the same, the diameter of the third circular tapered hole (42) away from the fourth circular tapered hole (43) is larger than the diameter of the third circular tapered hole (42) close to the fourth circular tapered hole (43), the diameter of the fourth circular tapered hole (43) close to the third circular tapered hole (42) is larger than the diameter of the fourth circular tapered hole (43) away from the third circular tapered hole (42), and the end of the fourth circular tapered hole (43) away from the third circular tapered hole (42) is communicated with the discharge end of the reactor (40). The fourth circular tapered hole (43) is provided with a discharge tube (44), the discharge tube (44) is communicated with the third circular tapered hole (42), and the top end and the bottom end of the discharge tube (44) are respectively connected with electrodes.

2. The fully automated graphene composite material preparation apparatus according to claim 1, characterized in that: The screw rod is provided with a helical blade, and one end of the screw rod is connected with the output end of the corresponding speed reducer (50).

3. The fully automated apparatus for preparing graphene composite material according to claim 2, characterized in that: The conveying pipe is provided with a protective gas conveying pipe (24) close to the inlet end, the gas inlet end of the protective gas conveying pipe (24) is communicated with a gas source, and the gas outlet end of the protective gas conveying pipe (24) is communicated with the inner cavity of the conveying pipe.

4. The fully automated apparatus for preparing graphene composite material according to claim 2, characterized in that: The pretreater (30) and the conveying pipe of the other conveying device are communicated through a pipeline (60), and the pipeline (60) is communicated with a waste gas vacuum pipe (62) through a gas outlet pipe (61).

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