Rapid waste plastic pyrolysis-catalysis device and test method

Abstract

The invention provides a rapid waste plastic pyrolysis-catalysis device and a test method, and belongs to the field of waste plastic utilization. The problems that a traditional waste plastic pyrolysis-catalytic reaction device is uneven in heating and low in pyrolysis rate in the pyrolysis process are solved. A rapid pyrolysis-catalytic reaction device for waste plastics comprises a pyrolysis device, a catalytic reaction device and a catalytic reaction device, the pyrolysis device comprises a pyrolysis container, a heat-carrying medium and a heating device, the heat-carrying medium is filled in the pyrolysis container and is in a liquid state at a high temperature, and the heating device is arranged on the wall of the pyrolysis container; the catalytic cracking device comprises a reducer pipe, an electromagnetic induction heating device and a catalytic reaction core, the catalytic reaction core is arranged on the upper half section of the reducer pipe, and a coil of the electromagnetic induction heating device is arranged outside the catalytic reaction core. The device is mainly used for pyrolyzing plastics.

Description

Technical Field

[0001] The invention belongs to the field of waste plastic utilization, and in particular relates to a waste plastic rapid pyrolysis-catalysis device and a test method. Background Art

[0002] The widespread use of plastic products is accompanied by the generation of a large amount of waste plastics. The global annual waste plastics generation can reach nearly 350 million tons, accounting for about 70-85% of the annual plastic production. At present, the common waste plastics treatment and utilization technologies include landfill and incineration. Nearly 12% of waste plastics are incinerated, nearly 79% of waste plastics are landfilled, and the recycling rate is only 9%.

[0003] Due to the continued potential harm of waste plastic landfill to the atmosphere, soil and water, this treatment method is increasingly restricted. At the same time, the incineration of waste plastics is often accompanied by the production of toxic gases such as polycyclic aromatic hydrocarbons, which can easily cause secondary pollution to the environment. In addition, waste plastics are materials containing a large amount of energy and organic polymers. Polyolefins in waste plastics, such as polyethylene (PE), polypropylene (PP) and polystyrene (PS), account for more than half of all waste plastic components. They have high calorific value and can be used as renewable resources. Direct burial or disposal is a waste of resources and does not conform to the concept of sustainable development. At present, pyrolysis catalysis of waste plastics to generate important carbon materials carbon nanotubes (CNTs) and clean energy hydrogen is an important way to utilize waste plastics at high value.

[0004] The traditional waste plastic pyrolysis-catalytic device is usually a two-stage pyrolysis-catalytic reaction system. The reaction device is divided into two parts, the first part is the pyrolysis section, and the second part is the catalytic cracking section. The waste plastic is first heated and pyrolyzed into volatiles in the pyrolysis section, and then the volatiles flow through the catalytic cracking section for further catalytic cracking to obtain the desired products of carbon nanotubes and hydrogen. However, this traditional waste plastic pyrolysis-catalytic device has obvious disadvantages: the waste plastic is heated unevenly during the pyrolysis stage, and there is a large temperature gradient, resulting in low pyrolysis efficiency. In addition, a large number of studies have shown that the rapid pyrolysis of waste plastics is conducive to the generation of gas components, and the gas components are more easily catalytically cracked into the desired carbon nanotubes and hydrogen in the catalytic cracking section. Therefore, the rapid pyrolysis of waste plastics can greatly improve the yield of the product. Therefore, it is very necessary to improve the traditional waste plastic pyrolysis-catalytic device to solve the problems of uneven heating in the pyrolysis section and slow pyrolysis rate. Summary of the invention

[0005] In view of this, the present invention aims to propose a waste plastic rapid pyrolysis-catalytic device and an experimental method, which connects the heat carrier with the traditional two-stage pyrolysis-catalytic device to solve the problems of uneven heating and slow pyrolysis rate in the traditional waste plastic pyrolysis-catalytic reaction device during the pyrolysis process, thereby improving the pyrolysis efficiency and increasing the product yield.

[0006] To achieve the above object, according to one aspect of the present invention, there is provided a waste plastic rapid pyrolysis-catalytic reaction device, comprising: A pyrolysis device, comprising a pyrolysis container, a heat carrier medium and a heating device, wherein the heat carrier medium is filled in the pyrolysis container and is liquid at high temperature, and the heating device is provided on the wall of the pyrolysis container; The catalytic cracking device comprises a reducer, an electromagnetic induction heating device and a catalytic reaction core. The catalytic reaction core is arranged in the upper half of the reducer, and the coil of the electromagnetic induction heating device is arranged outside the catalytic reaction core.

[0007] Furthermore, a flange is provided at the upper end of the pyrolysis container to ensure the airtightness of the pyrolysis process, and the flange includes: a feed channel, an air inlet channel, an air outlet channel, and a plurality of first temperature monitoring components; Furthermore, the catalytic cracking device is provided with an upper flange and a lower flange at the upper and lower ends respectively to ensure the airtightness of the catalytic cracking process, the upper flange includes: an air inlet channel and a plurality of second temperature monitoring components, and the lower flange is provided with a discharge channel.

[0008] Furthermore, the air inlet passage is connected to an inert gas supply assembly for conveying inert gas into the pyrolysis container and the reducer.

[0009] Furthermore, the feed channel is connected to a continuous feeding device for continuously conveying waste plastic particles into the pyrolysis container.

[0010] Furthermore, the air outlet channel is connected to the air inlet channel through a pipeline, so as to introduce the volatiles obtained by pyrolysis of waste plastics from the pyrolysis device into the catalytic cracking device.

[0011] Furthermore, the pyrolysis container is a silicon carbide container.

[0012] Furthermore, a metal porous catalyst is arranged in the catalytic reaction core.

[0013] Furthermore, the multiple first temperature monitoring components of the flange can be used to monitor the temperature of different positions of the heat carrier medium; the multiple second temperature monitoring components of the upper flange can be used to monitor the temperature of different positions of the catalytic reaction core, and the temperature monitoring components are all thermocouples.

[0014] According to another aspect of the present invention, there is provided a test method using the waste plastic rapid pyrolysis-catalytic device, comprising the following steps: S1. Exhaust the air in the pyrolysis unit and the catalytic cracking unit through the inert gas supply assembly, and install a gas sampling bag at the outlet end of the gas outlet channel; S2, respectively monitoring the temperature of the heat carrier medium and the temperature of the metal porous catalyst in the catalytic reaction core through the first temperature monitoring component and the second temperature monitoring component, and when the heat carrier medium and the porous catalyst both reach the target temperature and maintain it for a certain period of time, transporting the waste plastic particles into the feed channel; S3. After the waste plastic particles are in contact with the heat carrier medium and pyrolyzed by heat, volatiles are formed. The volatiles are transported from the outlet channel of the pyrolysis device to the inlet channel of the catalytic cracking device, and then flow through the metal porous catalyst in the catalytic reaction core to be further catalytically cracked. Finally, the gas is discharged from the outlet channel into the gas sampling bag; S4. After the reaction is completed, stop conveying the waste plastic particles and wait until all the waste plastics in the reactor device have reacted completely, turn off the heating device and the electromagnetic induction heating device, remove the gas sampling bag, and the test is over.

[0015] Compared with the prior art, the present invention has the following beneficial effects: 1. The reactor device is simpler in structure and low in cost, which can increase the cost control advantage; 2. The reactor device is provided with a pyrolysis device and a catalytic cracking device, which can form an ex situ catalytic cracking and perform a two-step reaction, thereby preventing the pyrolysis residue of the sample from poisoning the porous catalyst; 3. This reactor device can effectively solve the problem of uneven heating of waste plastics in the pyrolysis stage by introducing a heat carrier into the pyrolysis device, avoid incomplete pyrolysis of waste plastics, and improve pyrolysis efficiency; 4. This reactor device can achieve rapid pyrolysis of waste plastics by introducing a heat carrier into the pyrolysis device, resulting in a significant increase in the gas components in the volatiles, which is beneficial to the catalytic cracking of the volatiles and can significantly increase the yield of the final product. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings: Figure 1 This is a schematic structural diagram of a waste plastic rapid pyrolysis-catalytic cracking reaction device according to the present invention; Figure 2 The present invention provides a flow chart of an experimental method using a waste plastic rapid pyrolysis-catalytic cracking reaction device.

[0017] Pyrolysis device 1; pyrolysis container 1-1; heat carrier medium 1-2; heating device 1-3; waste plastic particles 1-4; flange 2; air inlet channel 2-1; feed channel 2-2; air outlet channel 2-3; first temperature monitoring component 3; first thermocouple 3-1; second thermocouple 3-2; pipeline 4; upper flange 5; air inlet channel 5-1; catalytic cracking device 6; reducer 6-1; electromagnetic induction heating device 6-2; catalytic reaction core 6-3; lower flange 7; outlet channel 7-1; second temperature monitoring component 8; DETAILED DESCRIPTION The following will be combined with the drawings in the embodiments of the present invention to clearly and completely explain the technical solutions in the embodiments of the present invention. It should be noted that the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict, and the described embodiments are only part of the embodiments of the present invention, not all of the embodiments.

[0018] It should be noted that the descriptions of the present invention regarding directions such as "left", "right", "left side", "right side", "upper", "lower", "top", "bottom", etc. are all defined based on the relationship between the orientations or positions shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the structure described must be constructed and operated in a specific orientation, and therefore, cannot be understood as a limitation on the present invention. In the description of the present invention, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0019] In the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0020] Referring to the accompanying drawings, this embodiment is described. According to one aspect of the present invention, there is provided a waste plastic pyrolysis-catalytic cracking reaction device, comprising: The pyrolysis device 1 comprises a pyrolysis container 1-1, a heat carrier 1-2 and a heating device 1-3. The heat carrier 1-2 is filled in the pyrolysis container 1-1 and is liquid at high temperature. The specific temperature is the pyrolysis temperature of the waste plastic during the experiment, such as the common 350°C, 400°C, and 500°C. The heating device 1-3 is provided on the wall of the pyrolysis container 1-1; Specifically, the lower end of the pyrolysis container 1-1 in the present application is sealed, and the size of the pyrolysis container 1-1 is related to the rate of continuous feeding, and can be designed according to actual conditions. The heat carrier 1-2 in the present application is molten salt, because molten salt has a lot of heat storage and is in a liquid state at high temperatures, and can be in direct contact with the waste plastic particles 1-4 to achieve uniform heat transfer. The heat carrier 1-2 accounts for approximately 2 / 3 of the volume of the pyrolysis container 1-1. The heating device 1-3 in the present application is a resistance wire heating coil, and the heating device 1-3 is close to the outer wall of the pyrolysis container 1-1. At the same time, an insulation layer is provided on the outer wall of the pyrolysis container 1-1 to prevent heat loss. The heating device 1-3 transfers heat to the pyrolysis container 1-1 through contact heat conduction, and then transfers the heat to the heat carrier 1-2.

[0021] The catalytic cracking device 6 includes a reducer 6-1, an electromagnetic induction heating device 6-2 and a catalytic reaction core 6-3, wherein the catalytic reaction core 6-3 is arranged in the upper half of the reducer 6-1, and the coil of the electromagnetic induction heating device 6-2 is arranged outside the catalytic reaction core 6-3; the radius of the upper part of the reducer 6-1 is slightly larger than the lower part, and this design can ensure that the porous catalyst in the catalytic reaction core 6-3 will not fall off. In addition, the height of the upper part is also much greater than the lower part. The upper part of the reducer 6-1 is almost the catalytic reaction core 6-3, leaving only a small area for caching gas flow, and the catalytic reaction core 6-3 is placed with a metal porous catalyst. The electromagnetic induction heating device 6-2 transmits high-frequency alternating current to the coil to generate a high-frequency alternating magnetic field, and the metal porous catalyst placed in the alternating magnetic field will generate eddy currents, thereby generating heat energy. The metal porous catalyst in the catalytic reaction core 6-3 is both a high-density heat source and a catalyst.

[0022] In this embodiment, a flange 2 is provided at the upper end of the pyrolysis container 1-1 to ensure the airtightness of the pyrolysis process, and the flange 2 includes: a feed channel 2-2, an air inlet channel 2-1, an air outlet channel 2-3, and a plurality of first temperature monitoring components 3; specifically, the feed channel 2-2 is a threaded pipe arranged at the center of the flange 2, and the height and inner diameter of the threaded pipe are related to the continuous feed rate and can be designed according to actual needs.

[0023] In this embodiment, the upper and lower ends of the catalytic cracking device 6 are respectively provided with an upper flange 5 and a lower flange 7 to ensure the airtightness of the catalytic cracking process. The upper flange 5 includes: an air inlet channel 5-1 and a plurality of second temperature monitoring components 8. The lower flange 7 is provided with a discharge channel 7-1. In this embodiment, the air inlet channel 2-1 is connected to an inert gas supply assembly for conveying inert gas into the pyrolysis container 1-1 and the reducer 6-1.

[0024] Specifically, the inert gas supply component can choose the method of a gas cylinder gas pump, and cooperate with a flow meter to deliver inert gas to the pyrolysis container 1-1 and the reducer 6-1. The inert gas can choose a gas source such as nitrogen. As for the specific connection method, the output end of the gas pump can be connected to the air inlet channel 2-1, and the air in the pyrolysis container 1-1 and the reducer 6-1 is emptied through the air inlet channel 2-1 to create an oxygen-free environment. It should be emphasized here that for the manufacture of an oxygen-free environment, the joints of each part of the present application should ensure airtightness to prevent leakage from occurring, which may cause the oxygen-free environment to be unable to be guaranteed.

[0025] In this embodiment, the feed channel 2-2 is connected to a continuous feeding device for continuously conveying waste plastics 1-4 into the pyrolysis container 1-1. For the purpose of this application, waste plastics are pyrolyzed and catalyzed to obtain important clean energy hydrogen and important carbon material carbon nanotubes, so it is necessary to avoid using high-grade electrical energy to prevent energy waste. As for the feeding method of waste plastics, a silo plus a screw conveyor can be used for transportation.

[0026] Specifically, the conveying pipeline of the screw conveying device can be connected to the discharge port of the silo, and then the waste plastic in the conveying pipeline can be driven to move by rotating the conveying screw shaft, and the discharge port of the conveying pipeline is connected to the inlet end of the feed channel 2-2 through a silicone tube, so that the material can smoothly enter the feed channel 2-2. The screw conveyor is driven by a stepper motor. By giving the stepper motor a very small frequency pulse, the stepper motor can be made to work approximately in a uniform rotation gear, and the speed is slow, and finally the plastic feeding rate is matched with the reactor size and the energy input in the reactor. In this embodiment, the stepper motor is adjusted to the lowest speed, and the final plastic particle feeding rate is about 30g / h.

[0027] In this embodiment, the outlet channel 2-3 is connected to the inlet channel 5-1 through a pipe 4, which is used to introduce the volatiles obtained by pyrolysis of waste plastics from the pyrolysis device 1 into the catalytic cracking device 6. Specifically, the pipe 4 needs to be insulated to prevent the volatiles from condensing in the pipe.

[0028] Specifically, the waste plastic particles 1-4 are heated by the heat carrier medium 1-2 to undergo a pyrolysis reaction to become volatiles. Due to rapid pyrolysis, most of the components of the volatiles are gas components below C6. The volatiles flow out of the gas outlet channel 2-3 along the pipeline 4 into the gas inlet channel 5-1, and then flow through the catalytic reaction core 6-3, and are further catalytically cracked in this area.

[0029] In this embodiment, the pyrolysis container 1-1 is a silicon carbide container. Silicon carbide has very good thermal conductivity and can meet the use conditions of this application.

[0030] In this embodiment, a metal porous catalyst is arranged in the catalytic reaction core 6-3. The porous catalyst here can catalyze the pyrolysis of waste plastics. Existing technology is used and will not be described here. The catalytic reaction core 6-3 as a whole can adopt a hollow or porous structure to carry the porous catalyst, so there is no specific limitation on the structural form. Any structure that can fix the metal porous catalyst and facilitate the reaction without affecting the passage of gas can be used in this application.

[0031] In this embodiment, the multiple first temperature monitoring components 3 on the flange 2 can be used to monitor the temperature of different positions of the heat carrier 1-2; this device diagram only lists the symmetrically arranged first thermocouples 3-1 and second thermocouples 3-2. Specifically, the number and position of thermocouples can be designed according to actual needs and device size. This setting is to solve the problem of uneven heating of waste plastics in the pyrolysis section. Therefore, it is necessary to ensure that the temperature of different positions of the heat carrier 1-2 is almost the same during the whole process, so multiple thermocouples are used for measurement. The multiple second temperature monitoring components of the upper flange 5 can be used to monitor the temperature of different positions of the catalytic reaction core. This device diagram only lists thermocouples 8. Specifically, the number and position of thermocouples can be designed according to actual needs and device size. This setting is to achieve precise temperature control of the catalytic reaction core temperature.

[0032] In this embodiment, the first temperature monitoring component 3 and the second temperature monitoring component 8 are both thermocouples, specifically K-type thermocouples. The thermocouples can be connected to a data acquisition system, and the data acquisition system can be based on existing technology, which will not be described in detail here.

[0033] According to another aspect of the present invention, there is provided a test method using the above-mentioned solar reactor device, comprising the following steps: S1. Exhaust the air in the pyrolysis unit and the catalytic cracking unit through the inert gas supply assembly, and install a gas sampling bag at the outlet end of the gas outlet channel; S2, respectively monitoring the temperature of the heat carrier medium and the temperature of the metal porous catalyst in the catalytic reaction core through two sets of temperature monitoring components. When the heat carrier medium and the porous catalyst reach the target temperature and maintain for 5 minutes, the waste plastic particles are transported into the feed channel and transported by a screw conveyor. The speed of the stepper motor of the screw conveyor is set to 1 revolution / min. S3. After the waste plastic particles are in contact with the heat carrier medium and pyrolyzed by heat, volatiles are formed. The volatiles are transported from the outlet channel of the pyrolysis device to the inlet channel of the catalytic cracking device, and then flow through the metal porous catalyst in the catalytic reaction core to be further catalytically cracked. Finally, the gas is discharged from the outlet channel into the gas sampling bag; S4. After the reaction is completed, stop conveying the waste plastic particles and wait until all the waste plastics in the reactor device have reacted completely, turn off the heating device and the electromagnetic induction heating device, remove the gas sampling bag, and the test is over.

[0034] Specifically, in order to ensure that the pyrolysis temperature is around 500°C, which is the most suitable temperature for plastic pyrolysis, the temperature cannot be too high or too low, and the uniformity of the temperature of the waste plastic at different points must be ensured. Therefore, in this embodiment, the thermocouple is connected to the temperature controller, and precise temperature control is achieved through the temperature controller. According to experimental measurements, the temperature of the heat medium at three different points can be stabilized at 500°C, with an error within 3°C, which meets the experimental requirements.

[0035] Specifically, the central temperature of the catalytic reaction core is taken as the catalytic cracking temperature. According to experimental measurements, the electromagnetic induction heating device can quickly reach 900°C in 5 minutes, and the heating rate is in line with the expectations of this device.

[0036] In order to meet the requirements of the pyrolysis device to adapt to the height of the electromagnetic induction device, the device is first placed on a scissor lift, which is fixed on a mobile platform. During the experiment, the forward, backward, left and right movement of the reactor can be directly achieved through the mobile platform; the up and down movement of the device is achieved by operating the scissor lift.

[0037] In the above introduction, the heating device, controller, sensor and control program that may be involved are all existing technologies and will not be elaborated here.

[0038] The embodiments of the present invention disclosed above are only used to help illustrate the present invention. The embodiments do not describe all the details in detail, nor do they limit the invention to the specific implementation methods described. According to the content of this specification, many modifications and changes can be made. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well.

Claims

1. A waste plastic rapid pyrolysis-catalysis device, characterized in that: include: A pyrolysis device (1) comprises a pyrolysis container (1-1), a heat carrier medium (1-2) and a heating device (1-3), wherein the heat carrier medium (1-2) is filled in the pyrolysis container (1-1) and is in a liquid state at high temperature, and the heating device (1-3) is arranged on the wall of the pyrolysis container (1-1); The catalytic cracking device (6) comprises a reducer (6-1), an electromagnetic induction heating device (6-2) and a catalytic reaction core (6-3), wherein the catalytic reaction core (6-3) is arranged in the upper half of the reducer (6-1), and the coil of the electromagnetic induction heating device (6-2) is arranged outside the catalytic reaction core (6-3).

2. A waste plastic rapid pyrolysis-catalysis device according to claim 1, characterized in that: The upper end of the pyrolysis container (1-1) is provided with a flange (2) for ensuring the airtightness of the pyrolysis process, and the flange (2) comprises: a feed channel (2-2), an air inlet channel (2-1), an air outlet channel (2-3) and a plurality of first temperature monitoring components (3).

3. A waste plastic rapid pyrolysis-catalysis device according to claim 2, characterized in that: The catalytic cracking device (6) is provided with an upper flange (5) and a lower flange (7) at the upper and lower ends respectively for ensuring the air tightness of the catalytic cracking process. The upper flange (5) comprises: an air inlet channel (5-1) and a plurality of second temperature monitoring components (8), and the lower flange (7) is provided with a discharge channel (7-1).

4. A waste plastic rapid pyrolysis-catalysis device according to claim 2, characterized in that: The air inlet channel (2-1) is connected to an inert gas supply assembly and is used to transport inert gas into the pyrolysis container (1-1) and the reducer (6-1).

5. The waste plastic rapid pyrolysis-catalysis device according to claim 2, characterized in that: The feed channel (2-2) is connected to a continuous feed device and is used to continuously transport waste plastic particles (1-4) into the pyrolysis container (1-1).

6. A waste plastic rapid pyrolysis-catalysis device according to claim 3, characterized in that: The gas outlet channel (2-3) is connected to the gas inlet channel (5-1) via a pipeline (4) and is used to introduce volatiles obtained by pyrolysis of waste plastics from the pyrolysis device (1) into the catalytic cracking device (6).

7. The waste plastic rapid pyrolysis-catalysis device according to claim 1, characterized in that: The pyrolysis container (1-1) is a silicon carbide container.

8. The waste plastic rapid pyrolysis-catalysis device according to claim 1, characterized in that: A metal porous catalyst is arranged in the catalytic reaction core (6-3).

9. The waste plastic rapid pyrolysis-catalysis device according to claim 3, characterized in that: The multiple first temperature monitoring components (3) of the flange (2) are used to monitor the temperature of different positions of the heat-carrying medium (1-2); the multiple second temperature monitoring components (8) of the upper flange (5) are used to monitor the temperature of different positions of the catalytic reaction core (6-3), and the first temperature monitoring components (3) and the second temperature monitoring components (8) are both thermocouples.

10. A test method using a waste plastic rapid pyrolysis-catalytic device as claimed in any one of claims 1 to 9, characterized in that: The following steps are involved: S1. exhausting the air in the pyrolysis device (1) and the catalytic cracking device (6) through an inert gas supply assembly, and installing a gas sampling bag at the outlet end of the gas outlet channel (7-1); S2, respectively monitoring the temperature of the heat medium (1-2) and the temperature of the metal porous catalyst in the catalytic reaction core (6-3) through the first temperature monitoring component (3) and the second temperature monitoring component (8), and when the heat medium (1-2) and the metal porous catalyst both reach the target temperature and maintain it for a certain period of time, transporting the waste plastic particles (1-4) into the feed channel (2-2); S3, the waste plastic particles (1-4) contact the heat carrier medium (1-2) and are pyrolyzed to form volatiles, which are transported from the outlet channel (2-3) to the inlet channel (5-1), and then flow through the catalytic reaction core (6-3) to be further catalytically cracked, and finally the gas is discharged from the outlet channel into the gas sampling bag; S4. After the reaction is completed, stop conveying the waste plastic particles (1-4) and wait until all the waste plastics in the reactor device have reacted, then turn off the heating device (1-3) and the electromagnetic induction heating device (6-2), remove the gas sampling bag, and the test is completed.

Images