Sampling system and sampling method for molten material of vacuum reactor

Abstract

The invention discloses a sampling system and a sampling method for a molten material of a vacuum reactor. The sampling system for the molten material of the vacuum reactor comprises a jacket sampling valve, a sampling container and a sampling discharging pipeline, one end of the jacket sampling valve is connected with a process pipeline, the other end of the jacket sampling valve is connected with the sampling discharging pipeline, the sampling container is provided with a container opening and a vacuumizing connector, and the sampling discharging pipeline is detachably connected with the container opening of the sampling container. A vacuumizing connector of the sampling container is detachably connected with a vacuum system, a heating medium is introduced into a jacket of the jacket sampling valve, and the temperature of the heating medium is higher than the melting point of materials in the process pipeline. According to the invention, the molten material can enter the sampling container through the suction of the vacuum system, and meanwhile, the heating medium is introduced into the jacket of the jacket sampling valve, and the temperature of the heating medium is higher than the melting point of the material in the process pipeline, so that the molten material is prevented from solidifying to block the jacket sampling valve, and the molten material is sampled in a vacuum environment.

Description

Technical Field

[0001] The invention relates to the technical field of chemical industry, in particular to a sampling system and a sampling method for molten materials in a vacuum reactor. Background Art

[0002] Polymer materials have a wide range of applications and a wide variety of types. Their production process is also relatively complex. In order to improve reaction efficiency and obtain target products, some processes require timely removal of reaction by-products under vacuum to ensure that the reaction proceeds in the positive direction and improve the reaction conversion rate. Since polymers have a high melting point and viscosity, in order to maintain good flow properties, the material temperature in some systems should be higher than its melting point and heated evenly to ensure that the material is in a molten state.

[0003] In the chemical production process, in order to understand the reaction of materials and optimize process parameters, the production equipment needs to conduct sampling and analysis, and adjust the operation plan in time according to the analysis results of the samples to ensure the safe and stable operation of the equipment. According to the differences in the process route, product plan, operating conditions, etc. of the production equipment, the requirements for sampling are different, and the difficulty of sampling is also different. The sampling system of the prior art transports the medium to the sampling container through the pressure or gravity in the system, but for the molten material in the vacuum system, since the polymer molten material itself has the characteristics of poor fluidity, in the vacuum system, the molten material cannot enter the sampling container by gravity. At the same time, the molten material is easily affected by the ambient temperature and is easy to solidify when it is cold. Therefore, the sampled sample is easy to accumulate at the entrance of the sampler, causing the molten material to solidify and block. Summary of the invention

[0004] Based on this, it is necessary to provide a sampling system and a sampling method for molten materials in a vacuum reactor in order to address the technical problem that the prior art cannot achieve sampling of molten materials in a vacuum system.

[0005] The present invention provides a sampling system for molten materials in a vacuum reactor. The vacuum reactor comprises an upstream device, a downstream device, and a process pipeline. The process pipeline connects the upstream device and the downstream device. The upstream device and the downstream device are respectively connected to a vacuum system. The sampling system comprises: a jacketed sampling valve, a sampling container, and a sampling discharge pipeline. One end of the jacketed sampling valve is connected to the process pipeline, and the other end is connected to the sampling discharge pipeline. The sampling container is provided with a container port and a vacuum extraction interface. The sampling discharge pipeline is detachably connected to the container port of the sampling container. The vacuum extraction interface of the sampling container is detachably connected to the vacuum system. A heat medium is introduced into the jacket of the jacketed sampling valve, and the temperature of the heat medium is higher than the melting point of the material in the process pipeline.

[0006] Furthermore, it also includes: a nitrogen valve, one end of which is connected to the sampling and discharging pipeline, and the other end of which is connected to an external nitrogen supply device.

[0007] Furthermore, it also includes: a joint, the vacuum interface of the sampling container is connected to the joint, and the joint is detachably connected to the vacuum system.

[0008] Furthermore, it also includes: a vacuum system valve, the vacuum system valve is fixedly connected to the vacuum system, and the connector is detachably connected to the vacuum system valve.

[0009] Furthermore, the container opening of the sampling container is arranged at the top, and the bottom of the sampling container is provided with a discharge port, and the discharge port is detachably connected to the bottom cover of the sampling container.

[0010] Furthermore, the side wall of the sampling container is fixedly connected to the handle.

[0011] The present invention provides a sampling method of the sampling system for molten materials in a vacuum reactor as described above, comprising:

[0012] Connecting the sampling container to the sampling discharge pipeline;

[0013] connecting the sampling container to the vacuum system;

[0014] Perform sampling operations;

[0015] After the sampling operation is completed, disconnecting the sampling container from the vacuum system;

[0016] Disconnect the sampling container from the sampling discharge pipeline and take the sampling container away;

[0017] The sampling container is placed in an electric heating jacket, and the electric heating jacket is turned on for heating. After the material is melted, it is poured out from the container opening of the sampling container for analysis.

[0018] Further, the performing of the sampling operation includes:

[0019] Controlling the vacuum system to evacuate the sampling container;

[0020] detecting a first pressure of a vacuum interface of the sampling container and a second pressure of the upstream device,

[0021] If the pressure reduction rate of the first pressure is lower than a set value, terminating sampling;

[0022] When the absolute value of the difference between the first pressure and the second pressure is less than a preset difference threshold, a heat medium is introduced into the jacket of the jacket sampling valve, and the jacket sampling valve is opened, wherein the temperature of the heat medium is higher than the melting point of the material in the process pipeline;

[0023] After a preset first time, the jacket sampling valve is closed;

[0024] The vacuum system is controlled to stop evacuating the sampling container.

[0025] Furthermore, the controlling the vacuum system to stop evacuating the sampling container comprises:

[0026] Nitrogen is introduced into the sampling and discharging pipeline, and after a preset second time, the vacuum system is controlled to stop evacuating the sampling container;

[0027] After the first pressure reaches a preset pressure threshold, the nitrogen is stopped from being supplied to the sampling and discharging pipeline.

[0028] Furthermore, the container opening of the sampling container is arranged at the top, the bottom of the sampling container is provided with a discharge port, and the discharge port is detachably connected to the bottom cover of the sampling container, and the sampling method further comprises:

[0029] Unscrew the bottom cover of the sampling container and clean the sampling container.

[0030] The present invention connects the jacket sampling valve with the process pipeline to take samples from the process pipeline, and simultaneously connects the sampling container with the vacuum system of the upstream and downstream equipment, so that the sampling container and the upstream and downstream equipment maintain the same vacuum environment, so that the molten material can enter the sampling container through the suction of the vacuum system, and at the same time, since the heat medium is introduced into the jacket of the jacket sampling valve, the temperature of the heat medium is higher than the melting point of the material in the process pipeline, thereby preventing the molten material from solidifying and clogging the jacket sampling valve, and realizing the sampling of the molten material under the vacuum environment. The sampling process of the present invention is airtight, which can ensure the smooth sampling of the molten material in the vacuum system, and at the same time ensure the personal safety of the operator. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is a system principle diagram of a sampling system for molten materials in a vacuum reactor according to an embodiment of the present invention;

[0032] Figure 2 This is a schematic diagram of heating a sampling container according to another embodiment of the present invention;

[0033] Figure 3 This is a working flow chart of a sampling method of a sampling system for molten materials in a vacuum reactor as described above according to the present invention;

[0034] Figure 4The following is a working flow chart of a sampling method of a sampling system for molten materials in a vacuum reactor as described above in a preferred embodiment of the present invention;

[0035] Figure 5 FIG. 1 is a flowchart of the sampling procedure of the best embodiment of the present invention.

[0036] Marking Description

[0037] 1. Upstream equipment; 2. Downstream equipment; 3. Process pipeline; 4. Vacuum system; 5. Jacketed sampling valve; 6. Sampling container; 7. Sampling discharge pipeline; 8. Nitrogen valve; 9. Connector; 10. Vacuum system valve; 11. Sampling container bottom cover; 12. Handle; 13. Buckle; 14. Electric heating jacket; 15. First pressure gauge; 16. Second pressure gauge. DETAILED DESCRIPTION

[0038] The specific embodiments of the present invention are further described below in conjunction with the accompanying drawings. The same components are represented by the same reference numerals. It should be noted that the words "front", "rear", "left", "right", "upper" and "lower" used in the following description refer to directions in the accompanying drawings, and the words "inner" and "outer" refer to directions toward or away from the geometric center of a specific component, respectively.

[0039] like Figure 1 The system schematic diagram of a sampling system for molten materials in a vacuum reactor according to an embodiment of the present invention is shown. The vacuum reactor comprises an upstream device 1, a downstream device 2, and a process pipeline 3. The process pipeline 3 connects the upstream device 1 and the downstream device 2. The upstream device 1 and the downstream device 2 are respectively connected to a vacuum system 4. The sampling system comprises: a jacketed sampling valve 5, a sampling container 6, and a sampling discharge pipeline 7. One end of the jacketed sampling valve 5 is connected to the process pipeline 3, and the other end is connected to the sampling discharge pipeline 7. The sampling container 6 is provided with a container port and a vacuum extraction interface. The sampling discharge pipeline 7 is detachably connected to the container port of the sampling container 6. The vacuum extraction interface of the sampling container 6 is detachably connected to the vacuum system 4. A heat medium is introduced into the jacket of the jacketed sampling valve 5.

[0040] Specifically, the sampling system for molten materials in a vacuum reactor of the present invention is used to collect polymer molten materials from pipelines of an upstream device 1 and a downstream device 2 of a vacuum reactor, and the entire system is used for sampling under a vacuum state.

[0041] The polymer melt is sent from the upstream device 1 to the downstream device 2 via the process pipeline 3 , and the jacketed sampling valve 5 is arranged on the process pipeline 3 and connected to the process pipeline 3 .

[0042] A heat medium may be introduced into the jacket of the jacket sampling valve 5 , and the temperature of the heat medium is higher than the melting point of the material in the process pipeline 3 , thereby ensuring that the temperature of the valve body is always higher than the melting point of the molten material.

[0043] In the prior art of molten material sampling, the sample is easily accumulated at the entrance of the sampler, that is, at the sampling valve of the sampler. However, since a heat medium with a temperature higher than the melting point of the material is introduced into the jacket sampling valve of the present invention, the molten material can be prevented from solidifying and clogging the jacket sampling valve.

[0044] In some embodiments, the jacket sampling valve 5 is a plunger jacket sampling valve, that is, a plunger-shaped jacket sampling valve.

[0045] The plunger jacket sampling valve has a valve core that is flush with the inner wall of the process pipeline 3 when the valve is closed, thereby avoiding blockage caused by condensation after material accumulation.

[0046] One end of the jacketed sampling valve 5 is connected to the process pipeline 3, and the other end is connected to the sampling discharge pipeline 7. The sampling container 6 is provided with a container port and a vacuum interface, and the sampling discharge pipeline 7 is detachably connected to the container port of the sampling container 6. When the sampling discharge pipeline 7 is connected to the container port of the sampling container 6, the molten material can be taken out from the process pipeline 3 into the sampling container 6 as a sample by opening the jacketed sampling valve 5. When the sampling is completed, the jacketed sampling valve 5 is closed. The vacuum interface of the sampling container 6 is detachably connected to the vacuum system 4. When the sampling container 6 is connected to the vacuum system 4, the vacuum system 4 evacuates the sampling container 6 so that the vacuum degree of the sampling container 6 is consistent with the vacuum degree of the upstream device 1, so that the molten material can enter the sampling container 6 through the suction of the vacuum system 4.

[0047] The present invention connects the jacket sampling valve with the process pipeline to take samples from the process pipeline, and simultaneously connects the sampling container with the vacuum system of the upstream and downstream equipment, so that the sampling container and the upstream and downstream equipment maintain the same vacuum environment, so that the molten material can enter the sampling container through the suction of the vacuum system, and at the same time, since the heat medium is introduced into the jacket of the jacket sampling valve, the temperature of the heat medium is higher than the melting point of the material in the process pipeline, thereby preventing the molten material from solidifying and clogging the jacket sampling valve, and realizing the sampling of the molten material under the vacuum environment. The sampling process of the present invention is airtight, which can ensure the smooth sampling of the molten material in the vacuum system, and at the same time ensure the personal safety of the operator.

[0048] like Figure 1As shown, a system schematic diagram of a sampling system for molten materials in a vacuum reactor according to another embodiment of the present invention, the vacuum reactor comprises an upstream device 1, a downstream device 2, and a process pipeline 3, the process pipeline 3 connects the upstream device 1 and the downstream device 2, the upstream device 1 and the downstream device 2 are respectively connected to a vacuum system 4, the sampling system comprises: a jacketed sampling valve 5, a sampling container 6, a sampling discharge pipeline 7, a nitrogen valve 8, a joint 9, a vacuum system valve 10, a sampling container bottom cover 11 and a handle 12, one end of the jacketed sampling valve 5 is connected to the process pipeline 3, and the other end is connected to the sampling discharge pipeline 7, the sampling container 6 is provided with a container port and a vacuum extraction interface, the sampling discharge pipeline 7 is detachably connected to the container port of the sampling container 6, the vacuum extraction interface of the sampling container 6 is detachably connected to the vacuum system 4, and a heat medium is introduced into the jacket of the jacketed sampling valve 5;

[0049] One end of the nitrogen valve 8 is connected to the sampling and discharging pipeline 7, and the other end is connected to an external nitrogen supply device.

[0050] The vacuum interface of the sampling container 6 is connected to the joint 9, and the joint 9 is detachably connected to the vacuum system 4. Specifically, the vacuum system valve 10 is fixedly connected to the vacuum system 4, and the joint 9 is detachably connected to the vacuum system valve 10;

[0051] The container opening of the sampling container 6 is arranged at the top, and the bottom of the sampling container 6 is provided with a discharge port, and the discharge port is detachably connected to the bottom cover 11 of the sampling container;

[0052] The side wall of the sampling container 6 is fixedly connected to the handle 12 .

[0053] Specifically, for molten materials in vacuum systems, the sampling process is difficult, which is reflected in the following aspects:

[0054] (1) The polymer molten material itself has the characteristic of poor fluidity. In the vacuum system, the molten material cannot enter the sampling container by gravity;

[0055] (2) Molten materials are easily affected by the ambient temperature and tend to solidify when cooled. If the sampling pipeline is long, it is easy to cause the sampling valve and pipeline to be blocked;

[0056] (3) Since the temperature of the molten material in the production system is relatively high, the process of disassembling and assembling the sampling container can easily cause burns to personnel, posing a greater safety risk.

[0057] In this embodiment, a vacuum sampling container is used to collect samples. After sampling, nitrogen is introduced to release the vacuum state. The pipeline is designed to be as short as possible so that the sample can represent the actual state inside the device and be more representative. At the same time, the molten material remaining in the replacement pipeline is prevented from being affected by the ambient temperature and causing blockage of the sampling valve and pipeline.

[0058] Specifically, the sampling system for molten materials in a vacuum reactor of the present invention is used to collect polymer molten materials from pipelines of an upstream device 1 and a downstream device 2 of a vacuum reactor, and the entire system is used for sampling under a vacuum state.

[0059] The polymer melt is sent from the upstream device 1 to the downstream device 2 via the process pipeline 3 , and the jacketed sampling valve 5 is arranged on the process pipeline 3 and connected to the process pipeline 3 .

[0060] A heat medium can be introduced into the jacket of the jacket sampling valve 5 , and the temperature of the heat medium is higher than the melting point of the material in the process pipeline 3 , thereby ensuring that the temperature of the valve body is always higher than the melting point of the molten material.

[0061] In some embodiments, the jacketed sampling valve 5 is a plunger jacketed sampling valve, that is, a plunger-shaped sampling valve body is covered with a jacket.

[0062] In some embodiments, when the jacketed sampling valve 5 is closed, the valve core is flush with the inner wall of the process pipeline 3 to avoid blockage caused by condensation after material accumulation.

[0063] One end of the jacket sampling valve 5 is connected to the process pipeline 3, and the other end is connected to the sampling discharge pipeline 7. The sampling container 6 is provided with a container port and a vacuum interface. The sampling discharge pipeline 7 is detachably connected to the container port of the sampling container 6. When the sampling discharge pipeline 7 is connected to the container port of the sampling container 6, the molten material can be taken out from the process pipeline 3 into the sampling container 6 as a sample by opening the jacket sampling valve 5. When the sampling is completed, the jacket sampling valve 5 is closed.

[0064] At the same time, a nitrogen line is set at the outlet of the plunger jacket sampling valve 5, one end of the nitrogen valve 8 is connected to the sampling discharge pipeline 7, and the other end is connected to an external nitrogen supply device. After sampling is completed, the nitrogen valve 8 is opened to feed nitrogen into the sampling discharge pipeline 7 to break the vacuum and purge the sampling discharge pipeline 7.

[0065] The outlet of the sampling discharge pipeline 7 is connected to the sampling container 6, and the sampling container 6 is also provided with a vacuum extraction interface, which is connected to the inlet of the vacuum system 4 of the downstream device 2 through a joint 9. Preferably, the sampling container 6 is made of stainless steel.

[0066] The vacuum system valve 10 is fixedly connected to the vacuum system 4, and the connector 9 is fixedly connected to the sampling container 6 and detachably connected to the vacuum system valve 10. In some embodiments, the connector 9 is a quick connector, so that the pipeline of the connector 9 and the vacuum system valve 10 can be quickly connected or disconnected.

[0067] In some embodiments, the vacuum system 4 is a vacuum pump, and the sampling container 6 is a sampling bottle.

[0068] In some embodiments, a buckle 13 is also included. The buckle 13 is installed at the container mouth of the sampling container 6. The outlet of the sampling discharge pipeline 7 is connected to the sampling container 6 through the buckle 13, which not only ensures the sealing of the sampling process, but also enables the easy disassembly of the sampling container 6 after sampling.

[0069] In some embodiments, the buckle 13 is a quick connector.

[0070] like Figure 2 As shown, a heating device is provided outside the sampling container 6, and the sample can be heated after being taken back to the laboratory to prevent the molten material from condensing in the sampling container 6 and affecting the reuse of the sampling container 6. The heating device can be an electric heating jacket 14, which is powered by a power supply so that the electric heating jacket 14 provides heat.

[0071] At the same time, in combination with the physical properties of the molten material, an arrangement port and a sampling container bottom cover 11 detachably connected to the discharge port are provided at the bottom of the sampling container 6. In special circumstances, such as when the material cannot be poured out through the sampling port, the sampling container bottom cover 11 can be opened to pour out the molten material, making it easy to thoroughly clean the sampling container 6 and realize the reuse of the sampling container 6.

[0072] Finally, the side wall of the sampling container 6 is fixedly connected to the handle 12, so that the sampling container 6 can be taken away conveniently through the handle 12, thereby avoiding burns to personnel and reducing safety risks.

[0073] This embodiment can effectively solve the problems existing in the sampling of polymer molten materials in a vacuum system. The sampling line is short and there is no need to replace the sampling system. It not only ensures the representativeness of the sample, but also effectively prevents the blockage of the jacket sampling valve and the sampling discharge line by heating the jacket sampling valve. This embodiment adds a nitrogen valve to break the vacuum and purge the sampling discharge line by introducing nitrogen. This embodiment provides a removable bottom cover at the bottom of the sampling container. In special cases, it is easy to thoroughly clean the sampling bottle, meet the requirements of reuse, and reduce operating costs. At the same time, by adding a handle, burns to personnel are avoided and safety risks are reduced.

[0074] like Figure 3 The flowchart of the sampling method of the sampling system of the molten material in the vacuum reactor as described above is shown in the present invention, comprising:

[0075] Step S301, connecting the sampling container 6 to the sampling discharge pipeline 7;

[0076] Step S302, connecting the sampling container 6 to the vacuum system 4;

[0077] Step S303, performing a sampling operation;

[0078] Step S304, after the sampling operation is completed, disconnecting the sampling container 6 from the vacuum system 4;

[0079] Step S305, disconnecting the sampling container 6 from the sampling discharge pipeline 7, and taking the sampling container 6 away;

[0080] Step S306, placing the sampling container 6 in the electric heating jacket 14, turning on the electric heating jacket 14 for heating, and pouring the material out from the container opening of the sampling container 6 for analysis after the material is melted.

[0081] Specifically, the sampling system operates as follows:

[0082] First, execute step S301 to connect the sampling container 6 to the sampling discharge pipeline 7;

[0083] Specifically, the sampling container 6 is connected to the sampling discharge pipeline 7 .

[0084] In some embodiments, a buckle 13 is further included, and the buckle 13 is installed at the container opening of the sampling container 6. The outlet of the sampling discharge pipeline 7 is connected to the sampling container 6 through the buckle 13. The connection of the sampling container 6 with the sampling discharge pipeline 7 includes:

[0085] The buckle 13 is rotated to ensure that the buckle 13 is rotated and tightened to ensure the sealing effect.

[0086] Then, step S302 is performed to connect the sampling container 6 to the vacuum system 4 .

[0087] Specifically, the sampling container 6 is connected to the vacuum system 4 via a hose through the connector 9 , wherein the hose of the vacuum system 4 is connected to the vacuum system valve 10 , and the connector 9 is connected to the vacuum system valve 10 .

[0088] Then, step S303 is executed to perform a sampling operation.

[0089] Specifically, the sampling operation can be performed by a sequence controller, and the sampling operation is performed by starting a sampling program of the sequence controller.

[0090] After the sampling operation is completed, step S304 is executed to disconnect the sampling container 6 from the vacuum system 4 .

[0091] Specifically, after the sampling program is completed, the connection between the joint 9 and the vacuum system valve 10 is disconnected, and the sampling container 6 is disconnected from the vacuum system 4.

[0092] Then, step S305 is executed to disconnect the sampling container 6 from the sampling discharge pipeline 7 and take the sampling container 6 away.

[0093] Specifically, the sampling container 6 is disconnected from the sampling discharge pipeline 7 , and the sampling container 6 is taken away through the handle 12 .

[0094] In some embodiments, the buckle 13 is rotated to disconnect the sampling container 6 from the sampling discharge pipeline 7 .

[0095] Finally, step S306 is performed to place the sampling container 6 in the electric heating jacket 14, turn on the electric heating jacket 14 for heating, and pour the material out from the container opening of the sampling container 6 for analysis after the material is melted.

[0096] Specifically, after the sampling container 6 is brought back to the laboratory, it is heated by the electric heating jacket 14, and the material is melted and poured out through the container mouth for analysis.

[0097] Among them, the jacket sampling valve 5 ensures that after sampling is completed, the sample will not accumulate at the inlet of the jacket sampling valve 5 to avoid solidification and blockage of the molten material; the sampling container 6 is connected to the existing vacuum system 4 through the joint 9 to ensure that the sample can smoothly enter the sampling container 6.

[0098] In this embodiment, a jacketed sampling valve is connected to a process pipeline to sample from the process pipeline, and at the same time, the sampling container is connected to the vacuum system of the upstream and downstream equipment, so that the sampling container and the upstream and downstream equipment maintain the same vacuum environment, so that the molten material can enter the sampling container through the suction of the vacuum system. At the same time, since a heat medium is introduced into the jacket of the jacketed sampling valve, the temperature of the heat medium is higher than the melting point of the material in the process pipeline, thereby preventing the molten material from solidifying and blocking the jacketed sampling valve, and realizing the sampling of the molten material under a vacuum environment. The sampling process of this embodiment is airtight, which can ensure the smooth sampling of the molten material in the vacuum system and the personal safety of the operator. At the same time, in the prior art, when the sampling container is taken back to the laboratory for analysis, the molten material is easy to condense into a solid, and it cannot be taken out of the sampling container for analysis. At the same time, the sampling container is not easy to clean, which affects the reuse of the sampling container. In this embodiment, a heatable electric heating sleeve is set outside the sampling container to prevent the sample from being unable to be taken out due to the condensation of the molten material, thereby realizing the reuse of the sampling container.

[0099] In one embodiment, performing the sampling operation includes:

[0100] Controlling the vacuum system 4 to evacuate the sampling container 6;

[0101] Detecting a first pressure of the vacuum interface of the sampling container 6 and a second pressure of the upstream device 1,

[0102] If the pressure reduction rate of the first pressure is lower than a set value, terminating sampling;

[0103] When the absolute value of the difference between the first pressure and the second pressure is less than a preset difference threshold, opening the jacket sampling valve 5;

[0104] After a preset first time, close the jacket sampling valve 5;

[0105] The vacuum system 4 is controlled to stop evacuating the sampling container 6 .

[0106] Specifically, the sampling operation can be performed by controlling multiple elements through a sequence controller.

[0107] First, the vacuum system 4 is controlled to evacuate the sampling container 6 .

[0108] Specifically, the vacuum system valve 10 is opened, so that the vacuum system 4 evacuates the sampling container 6 .

[0109] Then, the first pressure of the vacuum interface of the sampling container 6 and the second pressure of the upstream device 1 are detected.

[0110] Specifically, the first pressure PT-01 of the vacuum interface of the sampling container 6 is detected by the first pressure gauge 15 , and the second pressure PT-02 of the upstream device 1 is detected by the second pressure gauge 16 .

[0111] At this time, the first pressure PT-01 decreases at the set rate. If the pressure reduction rate of the first pressure PT-01 is lower than the set value, it means that there is a leak in the system. Sampling is suspended, and the operator checks and handles the connection and re-samples;

[0112] If the first pressure PT-01 decreases normally, when the difference between the first pressure PT-01 and the second pressure PT-02 is less than the preset difference threshold, it is normal to establish a vacuum in the sampling container 6. The difference threshold is preferably 1 kPa.

[0113] At this time, the jacket sampling valve 5 is opened, and the jacket sampling valve 5 is closed after the first time. Preferably, the first time is 5-10s.

[0114] Then, the vacuum system 4 is controlled to stop evacuating the sampling container 6 .

[0115] Specifically, the vacuum system valve 10 is controlled to be closed, thereby stopping the vacuuming of the sampling container 6 .

[0116] This embodiment uses automatic system control to determine whether sampling conditions are met based on pressure. The entire sampling process is automatically controlled to ensure that the sampling process is safe and reliable.

[0117] In one embodiment, controlling the vacuum system 4 to stop evacuating the sampling container 6 includes:

[0118] Nitrogen is introduced into the sampling and discharging pipeline 7, and after a preset second time, the vacuum system 4 is controlled to stop evacuating the sampling container 6;

[0119] After the first pressure reaches a preset pressure threshold, the nitrogen is stopped from being supplied to the sampling and discharging pipeline 7 .

[0120] Specifically, after closing the jacket sampling valve 5 , nitrogen is introduced into the sampling discharge pipeline 7 , and after a preset second time, the vacuum system 4 is controlled to stop evacuating the sampling container 6 .

[0121] Specifically, the nitrogen valve 8 is opened, nitrogen is introduced to break the vacuum and purge the sampling and discharging pipeline 7, and the vacuum system valve 10 is closed after the second time has passed. Preferably, the second time is 3-5 seconds.

[0122] Then, after the first pressure reaches a preset pressure threshold, the nitrogen is stopped from being fed into the sampling and discharging pipeline 7 .

[0123] Specifically, after the first pressure PT-01 reaches normal pressure, the nitrogen valve 8 is closed and the sampling is completed.

[0124] In the prior art, the sampling operation process is manually controlled. Since the purge time and vacuum time are unstable during the operation by the operator, it is easy to cause pipeline blockage or sampling failure. In this embodiment, the nitrogen purge time is set by a sequence controller, and the purge time and vacuum time are stable, which avoids pipeline blockage and improves the sampling success rate.

[0125] In one embodiment, the container opening of the sampling container 6 is arranged at the top, and the bottom of the sampling container 6 is provided with a discharge port, and the discharge port is detachably connected to the bottom cover 11 of the sampling container, and the sampling method further comprises:

[0126] Unscrew the bottom cover 11 of the sampling container and clean the sampling container 6 .

[0127] Specifically, when necessary, unscrew the sampling container bottom cover 11 of the sampling container 4, clean the sampling container 6 and keep it ready for use.

[0128] In this embodiment, a detachable bottom cover is provided at the bottom of the sampling container. Under special circumstances, it is easy to thoroughly clean the sampling container, meet the requirement of repeated use, and reduce the operating cost.

[0129] like Figure 4 The flowchart of the sampling method of the sampling system of the molten material in the vacuum reactor as described above is shown as the best embodiment of the present invention, comprising:

[0130] Step S401, connecting the sampling container 6 to the sampling discharge pipeline 7;

[0131] Step S402, connecting the sampling container 6 to the vacuum system 4 through the connector 9 via a hose;

[0132] Step S403, starting the sampling program of the sequence controller;

[0133] Step S404, after the sampling procedure is completed, the joint 9 is disassembled to disconnect the sampling container 6 from the vacuum system 4;

[0134] Step S405, disconnect the sampling container 6 from the sampling discharge pipeline 7, and take the sampling container 6 away through the handle 12;

[0135] Step S406, after the sampling container 6 is brought back to the laboratory, it is heated by the electric heating jacket 14, and the material is melted and poured out through the container mouth for analysis.

[0136] If necessary, unscrew the bottom cover 11 of the sampling container, clean the sampling container 6 and keep it ready for use.

[0137] The plunger jacket sampling valve 5 ensures that after sampling is completed, the sample will not accumulate at the inlet of the jacket sampling valve 5 to avoid clogging by solidification of the molten material; the sampling container 6 is connected to the existing vacuum system 4 through the joint 9 to ensure that the sample can smoothly enter the sampling container.

[0138] After taking the sample, nitrogen is allowed to enter the sampling container 6 by controlling the nitrogen valve 8. On the one hand, the sample in the sampling discharge pipeline 7 can be purged clean to avoid blockage. On the other hand, the vacuum state of the sampling container 6 can be eliminated to facilitate the removal of the sampling container 6.

[0139] The sampling process of this embodiment is airtight, which can ensure smooth sampling of molten materials in the vacuum system while ensuring the personal safety of operators.

[0140] like Figure 5 Shown is a workflow diagram of the sampling procedure of the preferred embodiment of the present invention, comprising:

[0141] Step S501, open the vacuum system valve 10, and the first pressure PT-01 decreases at a set rate. If the pressure reduction rate of the first pressure PT-01 is lower than the set value, it means that there is a leak in the system, and sampling is stopped. The operator checks and handles the connection and then resamples;

[0142] Step S502, the first pressure PT-01 of the sampling container 6 is reduced normally. When the difference between the first pressure PT-01 and the second pressure PT-02 is less than 1 kPa, it is normal to establish a vacuum in the sampling container 6;

[0143] Step S503, opening the jacket sampling valve 5, and closing the jacket sampling valve 5 after 5-10 seconds;

[0144] Step S504, open the nitrogen valve 8, purge the sampling and discharging pipeline 7, and close the vacuum system valve 10 after 3-5 seconds;

[0145] Step S505: After the first pressure PT-01 reaches normal pressure, the nitrogen valve 8 is closed and the sampling is completed.

[0146] This embodiment can effectively solve the existing problems of sampling polymer molten materials in a vacuum system. The sampling pipeline is short and there is no need to replace the sampling system. It not only ensures the representativeness of the sample, but also effectively prevents the clogging of the sampling valve and pipeline. This embodiment sets a heating device outside the sampling container to prevent the sample from being unable to be taken out due to the condensation of the molten material, thereby realizing the reuse of the sampling container. At the same time, a detachable bottom cover is set at the bottom of the sampling container. In special cases, it is easy to thoroughly clean the sampling container, meet the requirements of reuse, and reduce operating costs. The entire sampling process is automatically controlled to ensure that the sampling process is safe and reliable.

[0147] Example of implementation method

[0148] Embodiment 1:

[0149] In the polyester reaction system, a vacuum sampling system is required for sampling between vacuum reactors. A sampling system is set between vacuum reactor 1 and vacuum reactor 2. A snap 13 and a connector 9 are provided on the sampling container 6 for connecting with the material system and the vacuum system 4. The connector 9 is preferably a quick connector.

[0150] Connect the connector 9 to the vacuum system 4 via a hose;

[0151] Start the sampling sequence program;

[0152] After the sampling container 6 is taken back to the laboratory, it is heated by the electric heating jacket 14, and the material is melted and then taken out through the container opening for analysis;

[0153] Unscrew the bottom cover 11 of the sampling container, clean the sampling container and set it aside.

[0154] Embodiment 2:

[0155] According to the blockage of the sampling pipeline and the different viscosity characteristics of the polyester samples, the nitrogen purge time was adjusted to 20s, which effectively avoided condensation and blockage.

[0156] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A sampling system for molten materials in a vacuum reactor, the vacuum reactor comprising an upstream device (1), a downstream device (2), and a process pipeline (3), the process pipeline (3) connecting the upstream device (1) and the downstream device (2), the upstream device (1) and the downstream device (2) being respectively connected to a vacuum system (4), characterized in that: The sampling system comprises: a jacketed sampling valve (5), a sampling container (6) and a sampling discharge pipeline (7); one end of the jacketed sampling valve (5) is connected to the process pipeline (3), and the other end is connected to the sampling discharge pipeline (7); the sampling container (6) is provided with a container port and a vacuum interface; the sampling discharge pipeline (7) is detachably connected to the container port of the sampling container (6); the vacuum interface of the sampling container (6) is detachably connected to the vacuum system (4); a heat medium is introduced into the jacket of the jacketed sampling valve (5); and the temperature of the heat medium is higher than the melting point of the material in the process pipeline (3).

2. The sampling system for molten materials in a vacuum reactor according to claim 1, characterized in that: Also includes: A nitrogen valve (8), one end of the nitrogen valve (8) is connected to the sampling and discharging pipeline (7), and the other end is connected to an external nitrogen supply device.

3. The sampling system for molten materials in a vacuum reactor according to claim 1, characterized in that: It also comprises a joint (9), the vacuum interface of the sampling container (6) is connected to the joint (9), and the joint (9) is detachably connected to the vacuum system (4).

4. The sampling system for molten materials in a vacuum reactor according to claim 3, characterized in that: It also comprises: a vacuum system valve (10), wherein the vacuum system valve (10) is fixedly connected to the vacuum system (4), and the connector (9) is detachably connected to the vacuum system valve (10).

5. The sampling system for molten materials in a vacuum reactor according to claim 1, characterized in that: The container opening of the sampling container (6) is arranged at the top, and the bottom of the sampling container (6) is provided with a discharge opening, and the discharge opening is detachably connected to the bottom cover (11) of the sampling container.

6. The sampling system for molten materials in a vacuum reactor according to claim 1, characterized in that: The side wall of the sampling container (6) is fixedly connected to the handle (12).

7. A sampling method for a molten material sampling system of a vacuum reactor according to any one of claims 1 to 6, characterized in that: include: Connecting the sampling container (6) to the sampling discharge pipeline (7); Connecting the sampling container (6) to the vacuum system (4); Perform sampling operations; After the sampling operation is completed, the sampling container (6) is disconnected from the vacuum system (4); Disconnect the sampling container (6) from the sampling discharge pipeline (7) and take the sampling container (6) away; The sampling container (6) is placed in an electric heating jacket (14), and the electric heating jacket (14) is turned on for heating. After the material is melted, it is poured out from the container opening of the sampling container (6) for analysis.

8. The sampling method of the sampling system for molten materials in a vacuum reactor according to claim 7, characterized in that: The performing of the sampling operation comprises: Controlling the vacuum system (4) to evacuate the sampling container (6); detecting a first pressure of the vacuum interface of the sampling container (6) and a second pressure of the upstream device (1), If the pressure reduction rate of the first pressure is lower than a set value, terminating sampling; When the absolute value of the difference between the first pressure and the second pressure is less than a preset difference threshold, a heat medium is introduced into the jacket of the jacket sampling valve (5), and the jacket sampling valve (5) is opened, wherein the temperature of the heat medium is higher than the melting point of the material in the process pipeline (3); After a preset first time, closing the jacket sampling valve (5); The vacuum system (4) is controlled to stop evacuating the sampling container (6).

9. The sampling method of the sampling system for molten materials in a vacuum reactor according to claim 8, characterized in that: The controlling the vacuum system (4) to stop evacuating the sampling container (6) comprises: Nitrogen is introduced into the sampling and discharging pipeline (7), and after a preset second time, the vacuum system (4) is controlled to stop evacuating the sampling container (6); After the first pressure reaches a preset pressure threshold, the nitrogen is stopped from being supplied to the sampling and discharging pipeline (7).

10. The sampling method of the sampling system for molten materials in a vacuum reactor according to claim 7, characterized in that: The container opening of the sampling container (6) is arranged at the top, and the bottom of the sampling container (6) is provided with a discharge port, and the discharge port is detachably connected to the bottom cover (11) of the sampling container. The sampling method further comprises: Unscrew the bottom cover (11) of the sampling container and clean the sampling container (6).

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