Automatic particle sampling and detecting device, electrolytic aluminum system and control method of electrolytic aluminum system

Abstract

The invention belongs to the technical field of particle detection devices, and particularly relates to an automatic particle sampling and detecting device, an electrolytic aluminum system and a control method of the electrolytic aluminum system. Information about the number of particles and the volume of each particle may be obtained. According to the device, the stirring device is arranged in the detection pool, and the stirring device is used for uniformly distributing sample particles in the electrolyte, so that the detection deviation caused by non-uniform particle distribution is prevented. The automatic particle sampling and detecting device is integrated and installed on the fluorine-loaded aluminum oxide conveying pipeline, the working parameters of the discharging system and the electrolytic cell can be regulated and controlled in real time according to particle size information, the discharging time, the discharging amount and the parameters of the electrolytic cell can be adjusted in time according to information such as the particle size of materials, faults of the electrolytic cell can be avoided, and the service life of the electrolytic cell is prolonged. The production efficiency can be effectively improved, and the energy consumption is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of particle detection devices, and particularly relates to a particle automatic sampling and detection device, an electrolytic aluminum system and a control method thereof. Background Art

[0002] In the actual production process, during the production stage of alumina, the control of its fineness is unstable. At the same time, for different batches of alumina, during the entire transportation process, due to differences in their abrasion indices, the fineness of the finally fluorine-loaded alumina will also vary. This will result in a large deviation in the fineness value of different batches of alumina when they finally enter the electrolytic cell. When the fineness of alumina changes significantly, it will cause a decrease or increase in the feeding amount of the constant-volume feeder, and it will also affect the solubility of alumina in the electrolyte. If process parameters such as the feeding interval and the feeding connection time are not adjusted in time, the electrolytic cell may have a problem of too low alumina concentration, which may further lead to a large-area anode effect or cause precipitation, thus affecting normal production. Therefore, during the production process, it is necessary to detect the fineness of different batches of alumina before it enters the constant-volume feeder and adjust process parameters such as the feeding interval and the feeding connection time in a timely manner according to the detected fineness of the alumina.

[0003] Currently, the detection of the particle size of fluorine-loaded alumina still uses the traditional screening method, which has drawbacks such as inability to ensure the representativeness of the analyzed samples, systematic errors in detection, and large human interference factors. Moreover, the number of samples analyzed is too small, the detection cycle is long, and it cannot effectively reflect the change of the particle size of fluorine-loaded alumina in the production process in a timely manner, and cannot play an auxiliary decision-making role in production in a timely manner. Summary of the Invention

[0004] Aiming at the problems existing in the prior art, the present invention provides a particle automatic sampling and detection device, an electrolytic aluminum system and a control method thereof, which can automatically sample, automatically detect the particle size of particles during transportation, and can output the detection results in real time, and feedback the detection results to the total control system of the electrolytic aluminum system. The total control system can adjust the feeding time and feeding amount of the electrolytic cell in a timely manner according to the particle size results detected in real time, solving the problems of poor sampling representativeness, long detection cycle, and inability to output detection results in real time in the prior art. The specific contents of the present invention are as follows:

[0005] The first aspect of the present invention protects a particle automatic sampling and detection device, including a sampling device, a pneumatic conveying system, a particle size detection system, and a sub-control system.

[0006] The sampling device includes a sampling pipe, a sampling control mechanism, and a sample delivery pipe. A sampling port is provided on the side wall of the sampling pipe, and the input end of the sample delivery pipe is externally connected to the sampling port. The sampling control mechanism is arranged on the sampling pipe. The function of the sampling pipe is to be installed on the particle delivery pipeline and take samples when needed. Preferably, the sampling pipe is installed vertically on the vertical section of the particle delivery pipeline. The sampling control mechanism can be a valve or other mechanism. During sampling, the sampling control mechanism connects the particle delivery path to the sampling port, enabling the particle sample to enter the sample delivery pipe through the sampling port.

[0007] The pneumatic conveying system is connected to the sample delivery pipe. The function of the pneumatic conveying system is to provide high-pressure gas for the sample delivery pipe. The high-pressure gas blows from the feed end to the discharge end of the sample delivery pipe, causing the sample particles to be conveyed along the sample delivery pipe to the target position under the action of the high-pressure air flow.

[0008] The particle size detection system includes a mixing device, a sample bin, a return pipeline, a detection sampling pipe, and a particle size detection device.

[0009] The feed port of the mixing device is connected to the output end of the sample delivery pipe. The function of the mixing device is to mix the particle samples obtained by the sampling pipe evenly.

[0010] The sample bin is connected to the discharge port of the mixing device. The sample bin is provided with a discharge port, and the discharge port of the sample bin is respectively connected to the return pipeline and the detection sampling pipe. A first control valve and a second control valve are respectively arranged on the return pipeline and the detection sampling pipe. The function of the sample bin is to receive the mixed particle samples. The function of the detection sampling pipe is to conduct secondary sampling from the mixed particle samples and convey the samples to the particle size detection device for particle size detection. The function of the return pipeline is to return the remaining sample particles after secondary sampling to the production system for continued production. In the device of the present invention, by arranging a mixing device and a detection sampling pipe in the particle size detection system, secondary mixing and secondary sampling can be performed on the samples taken by the sampling pipe, which can further ensure the randomness and reliability of sampling and improve the accuracy of detection. By arranging a return pipeline behind the sample bin in the present invention, the remaining materials after sampling can be recycled into the production system for the second time, avoiding waste of raw materials.

[0011] The particle size detection device includes a detection pool, a circulation pipe, a circulation pump, an electrode system, a sensing device and a computing device. The detection pool is connected to the discharge end of the detection sampling pipe; the circulation pipe includes a first end and a second end, the end of the first end of the circulation pipe is closed and arranged in the detection pool, a detection port is opened on the side wall of the first end of the circulation pipe, and a first electrode inlet is also arranged on the circulation pipe; the second end of the circulation pipe is connected to the detection pool; the circulation pump is arranged on the circulation pipe; the electrode system includes a first electrode and a second electrode, the first electrode extends from the first electrode inlet into the circulation pipe and is arranged at the first end of the circulation pipe; the second electrode is arranged in the detection pool; the first electrode and the second electrode are located at different heights in the detection pool The sensing device includes an input end and an output end, wherein the input end of the sensing device is connected to the first electrode and the second electrode, and the output end of the sensing device is connected to the computing device; the particle size detection device of the present invention is a particle size detection device designed based on the online Coulter principle, wherein the detection port on the side wall of the first end of the circulation tube allows the liquid inside and outside the first end of the circulation tube to communicate, and an electric field is established in the electrolyte through a first electrode and a second electrode, one in the hole and the other outside the hole, respectively. Current passes through the detection port, and an "induction zone" is generated near the detection port. During detection, the circulation pump on the circulation tube is turned on, so that the particles to be tested suspended in the electrolyte pass through the induction zone, and the immersed volume of the particles replaces the electrolyte of the same volume, causing a short-term change in the resistance of the induction zone. This resistance change results in the generation of corresponding current pulses or voltage pulses. By measuring the number of electric pulses and their amplitudes, and calculating by the computing device, information about the number of particles and the volume of each particle can be obtained;

[0012] The sub-control system is connected with the sampling control mechanism, the pneumatic conveying system, the first control valve, the second control valve, and the computing device. The sub-control system is used to control the actions of the sampling control mechanism, the pneumatic conveying system, the first control valve, and the second control valve, and to receive and transmit the detection results obtained by the computing device.

[0013] Furthermore, the particle size detection device also includes a stirring device, which is arranged in the detection pool and connected to the sub-control system. The function of the stirring device is to make the sample particles evenly distributed in the electrolyte to prevent detection deviation caused by uneven particle distribution.

[0014] Further, the particle size detection device further includes a liquid inlet pipe and a liquid outlet pipe respectively connected to the detection cell. An inlet pump and an inlet valve are provided on the liquid inlet pipe; an outlet pump and an outlet valve are provided on the liquid outlet pipe; the inlet pump, the outlet pump, the inlet valve, and the outlet valve are respectively connected to the sub-control system. The detection cell of this device is connected to the liquid inlet pipe and the liquid outlet pipe, and electrolyte can be added to the detection cell after sampling. With the agitation of the agitation device, a suspension with uniform particle distribution can be obtained for particle size detection. After the detection is completed, the liquid and particles in the detection cell can be discharged through the liquid outlet pipe. When needed, the detection cell can be cleaned by feeding liquid through the liquid inlet pipe for the next detection. The particle size detection device disclosed in the present invention, in cooperation with devices such as the sub-control system, can achieve multiple consecutive detections and real-time output of detection results.

[0015] Further, the sensing device is a pulse resistance sensing device and / or a pulse current sensing device.

[0016] Further, a flap connection port is provided on the side of the sampling pipe opposite to the side where the sampling port is located. The distance between the side where the sampling port of the sampling pipe is located and the side where the flap connection port is located is D;

[0017] The sampling control mechanism includes a flap mechanism. The flap mechanism includes a first flap, a second flap, a flap connection mechanism, and a flap driving device. The first flap is arranged inside the sampling pipe, and the length of the first flap is L; the second flap is arranged outside the sampling pipe; the flap connection mechanism is arranged at the flap connection port and is rotatably connected to the sampling pipe wall. The upper ends of the first flap and the second flap are connected through the flap connection mechanism; the included angle between the first flap and the second flap is α, and L≥D / sinα; the flap driving device is connected to the second flap. Preferably, the flap driving device is a cylinder. When sampling is required, the second flap is driven by the cylinder to approach the outer wall of the sampling pipe. The second flap drives the bottom end of the first flap to approach the other side of the sampling pipe through the flap connection mechanism. At this time, the second flap blocks the conveyance of particles in the particle conveyance system path. The particles are guided by the second flap and enter the sampling port on the side wall of the sampling pipe and then enter the sample conveyance pipe to complete the sampling. It should be noted that when the first flap contacts the inner wall of the sampling pipe on the side opposite to the side where the flap connection port is located under the drive of the second flap, it is necessary to ensure that the contact point between the first flap and the inner wall of the sampling pipe is downstream of the sampling port (here, downstream is relative to the particle conveyance direction in the production system). Most preferably, the sampling port is adjacent to the contact point between the first flap and the inner wall of the sampling pipe, so as to ensure that the particles can enter the sampling port under the guidance of the first flap during sampling.

[0018] Further, the flap connection mechanism includes a connecting shaft disposed within the flap connection port and rotatably connected to the sampling tube at both ends; the upper ends of the first flap and the second flap are respectively fixedly connected to the connecting shaft.

[0019] Further, the pneumatic conveying system includes a high-pressure gas system, a high-pressure gas pipe connected to the high-pressure gas system, and a third control valve disposed on the high-pressure gas pipe; an air inlet is provided on the side wall of the input end of the sample conveying pipe, and the outlet end of the high-pressure gas pipe is inclinedly connected to the air inlet on the sample conveying pipe towards the middle section of the sample conveying pipe, so as to ensure that the high-pressure gas blows from the input end of the sample conveying pipe to the output end of the sample conveying pipe, thereby realizing the pneumatic conveying of the granular sample; the third control valve is connected to the sub-control system.

[0020] In the second aspect of the present invention, an electrolytic aluminum system with the described automatic granular sampling and detection device is protected, including a fluorine-bearing alumina conveying pipeline, a feeding system, an electrolytic cell, and a master control system. The discharging end of the fluorine-bearing alumina conveying pipeline is connected to the feeding system, the feeding system is connected to the electrolytic cell, the master control system is respectively connected to the feeding system and the electrolytic cell. The sampling tube divides the fluorine-bearing alumina conveying pipeline into two sections, and both ends of the sampling tube are respectively connected to the fluorine-bearing alumina conveying pipelines at its two ends; the discharging end of the return pipeline is connected to the fluorine-bearing alumina conveying pipeline; the diameter of the detection port is larger than the particle size of the fluorine-bearing alumina and smaller than twice the particle size of the fluorine-bearing alumina; an electrolyte is carried in the detection pool, and both the first electrode and the second electrode are immersed in the electrolyte; the sub-control system is connected to the master control system for transmitting the particle size detection result to the master control system.

[0021] In the third aspect of the present invention, a control method for the described electrolytic aluminum system is protected, including:

[0022] S1, primary sampling: The sub-control system sends a sampling instruction to the sampling control mechanism, and the sampling control mechanism controls to intercept part of the fluorine-bearing alumina particles in the fluorine-bearing alumina conveying pipeline and enter the sample conveying pipe; meanwhile, the sub-control system controls to turn on the pneumatic conveying system, and under the action of high-pressure gas, the fluorine-bearing alumina particles that have entered the sample conveying pipe are conveyed to the mixing device, and the pneumatic conveying system is turned off after sampling ends;

[0023] S2, mixing: The sub-control system controls the mixing device to mix the fluorine-bearing alumina particles. After mixing ends, the sub-control system controls the mixing device to discharge materials to the sample bin;

[0024] S3. Secondary Sampling and Return Feeding: The sub-control system controls the pneumatic conveying system to start, and at the same time, the first control valve and the second control valve are opened, so that part of the fluorine-bearing alumina particles return from the return pipeline to the fluorine-bearing alumina conveying pipeline, and the other part of the fluorine-bearing alumina particles enter the detection cell from the detection sampling pipe;

[0025] S4. Particle Size Detection: The sub-control system controls the circulation pump to start, so that the electrolyte containing fluorine-bearing alumina particles enters the circulation pipe from the detection port of the circulation pipe. When the fluorine-bearing alumina particles pass through the detection port, a potential pulse is generated between the first electrode and the second electrode. The induction device transmits the potential pulse signal to the calculation device, and the calculation device calculates the particle size information of the fluorine-bearing alumina particles and transmits the particle size information to the master control device in real time;

[0026] S5. Feeding Control and Electrolytic Cell Parameter Regulation: The master control system adjusts the working parameters of the feeding system and the electrolytic cell in real time according to the particle size information of the fluorine-bearing alumina particles.

[0027] Further, after the particle size detection is completed, the sub-control system controls the discharge of the electrolyte containing fluorine-bearing alumina particles in the detection cell, and then controls the injection of new electrolyte into the detection cell.

[0028] Advantages of the present invention:

[0029] (1) The automatic particle sampling and detection device disclosed by the present invention is provided with a mixing device and a detection sampling pipe in the particle size detection system, which can perform secondary mixing and secondary sampling on the samples taken by the sampling pipe, further ensuring the randomness and reliability of sampling and improving the accuracy of detection. The present invention is provided with a return pipeline behind the sample bin, which can recycle the remaining sampled materials into the production system for the second time, avoiding waste of raw materials.

[0030] (2) The particle size detection device of the present invention is a particle size detection device designed based on the online Coulter principle. The detection port on the side wall of the first end of the circulation pipe makes the liquid inside and outside the first end of the circulation pipe communicate, and an electric field is established in the electrolyte through the first electrode and the second electrode, one inside the hole and the other outside the hole. There is current passing through the detection port, generating an "induction zone" near the detection port. During detection, the circulation pump on the circulation pipe is started, so that the particles to be measured suspended in the electrolyte pass through the induction zone. The immersed volume of the particles replaces the electrolyte of the same volume, causing a short-term change in the resistance of the induction zone. This resistance change causes corresponding current pulses or voltage pulses to be generated. By measuring the number and amplitude of the electrical pulses and calculating through the calculation device, information about the number of particles and the volume of each particle can be obtained. A stirring device is provided in the detection cell of this device, and the function of the stirring device is to make the sample particles evenly distributed in the electrolyte, preventing detection deviation caused by uneven particle distribution.

[0031] (3) The particle automatic sampling and detection device disclosed by the present invention is provided with a sub-control system, and the sub-control system is connected to the sampling control mechanism, the pneumatic conveying system, the first control valve, the second control valve, and the computing device. The actions of the sampling control mechanism, the pneumatic conveying system, the first control valve, and the second control valve can be automatically controlled through the sub-control system, and the detection results obtained by the computing device can be received and transmitted.

[0032] (4) For the aluminum electrolysis system with the particle automatic sampling and detection device disclosed by the present invention, the particle automatic sampling and detection device is integrated and installed on the carrier alumina fluoride conveying pipeline of the aluminum electrolysis system, and the sub-control system is connected to the main control system of the aluminum electrolysis system. The particle size detection results can be transmitted to the main control system in real time. The main control system can adjust the working parameters of the feeding system and the electrolytic cell in real time according to the particle size information, so that the feeding time, the feeding amount, and the electrolytic cell parameters can be adjusted in time according to information such as the particle size of the material, which can avoid the occurrence of electrolytic cell failures and effectively improve production efficiency and save energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a schematic structural diagram of the aluminum electrolysis system with the particle automatic sampling and detection device disclosed by the present invention;

[0034] Figure 2 It is a schematic structural diagram of the sampling device in the particle automatic sampling and detection device disclosed by the present invention;

[0035] Figure 3 It is a schematic structural diagram of the particle size detection device in the particle automatic sampling and detection device disclosed by the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0036] The present invention will be described in detail below in conjunction with the drawings and specific embodiments. The following embodiments do not limit the content of the invention described in the claims in any way. In addition, all the contents shown in the following embodiments are not limited to those necessary for the solution of the invention described in the claims.

[0037] Refer to the attached Figures 1 - 3, the arrows in the figure indicate the material flow direction. An automatic particle sampling and detection device includes a sampling device 1, a pneumatic conveying system 2, a particle size detection system, and a sub-control system. The sampling device 1 includes a sampling pipe 9, a sampling control mechanism, and a sample delivery pipe 10. A sampling port is provided on the side wall of the sampling pipe 9, and the input end of the sample delivery pipe 10 is externally connected to the sampling port. The sampling control mechanism is arranged on the sampling pipe 9. The function of the sampling pipe 9 is to be installed on the particle conveying pipeline 8 to take samples when needed. Preferably, the sampling pipe 9 is installed vertically on the vertical section of the particle conveying pipeline 8. The sampling control mechanism can be a valve or other mechanism. During sampling, the sampling control mechanism connects the particle conveying path to the sampling port, enabling the particle sample to enter the sample delivery pipe 10 from the sampling port. The pneumatic conveying system 2 is connected to the sample delivery pipe 10. The function of the pneumatic conveying system 2 is to provide high-pressure gas for the sample delivery pipe 10. The high-pressure gas blows from the feed end to the discharge end of the sample delivery pipe 10, causing the sample particles to be conveyed along the sample delivery pipe 10 to the target position under the action of the high-pressure air flow. The particle size detection system includes a mixing device 3, a sample bin 4, a return pipeline 5, a detection sampling pipe 6, and a particle size detection device 7. The feed inlet of the mixing device 3 is connected to the output end of the sample delivery pipe 10. The function of the mixing device 3 is to mix the particle samples obtained by the sampling pipe 9 evenly. The sample bin 4 is connected to the discharge outlet of the mixing device 3. The sample bin 4 is provided with a discharge outlet, and the discharge outlet of the sample bin 4 is respectively connected to the return pipeline 5 and the detection sampling pipe 6. A first control valve and a second control valve are respectively arranged on the return pipeline 5 and the detection sampling pipe 6. The function of the sample bin 4 is to receive the mixed particle samples. The function of the detection sampling pipe 6 is to conduct secondary sampling from the mixed particle samples and deliver the samples to the particle size detection device 7 for particle size detection. The function of the return pipeline 5 is to return the sample particles remaining after secondary sampling to the production system for continued production. In the device of the present invention, by arranging the mixing device 3 and the detection sampling pipe 6 in the particle size detection system, the samples taken by the sampling pipe 9 can be mixed and sampled twice, which can further ensure the randomness and reliability of sampling and improve the accuracy of detection. By arranging the return pipeline 5 behind the sample bin 4 in the present invention, the remaining materials after sampling can be recycled into the production system twice, which can avoid waste of raw materials.The particle size detection device 7 includes a detection pool 17, a circulation pipe 18, a circulation pump 19, an electrode system, a sensing device 22 and a computing device. The detection pool 17 is connected to the discharge end of the detection sampling tube 6; the circulation pipe 18 includes a first end and a second end, the end of the first end of the circulation pipe 18 is closed and arranged in the detection pool 17, a detection port is provided on the side wall of the first end of the circulation pipe 18, and a first electrode 20 inlet is also provided on the circulation pipe 18; the second end of the circulation pipe 18 is connected to the detection pool 17; the circulation pump 19 is arranged on the circulation pipe 18; the electrode system includes a first electrode 20 and a second electrode 21, the first electrode 20 extends from the first electrode 20 inlet into the circulation pipe 18 and is arranged at the first end of the circulation pipe 18; the second electrode 21 is arranged in the detection pool 17; the first electrode 20 and the second electrode The electrodes 21 are located at different heights in the detection pool 17; the induction device 22 includes an input end and an output end, the input end of the induction device 22 is connected to the first electrode 20 and the second electrode 21, and the output end of the induction device 22 is connected to the computing device; the particle size detection device 7 of the present invention is a particle size detection device 7 designed based on the online Coulter principle, the detection port on the side wall of the first end of the circulation tube 18 allows the liquid inside and outside the first end of the circulation tube 18 to communicate, and an electric field is established in the electrolyte through the first electrode 20 and the second electrode 21, one in the hole and the other outside the hole, and a current passes through the detection port, and a "sensing area" is generated near the detection port. During detection, the circulation pump 19 on the circulation tube 18 is turned on, so that the particles to be tested suspended in the electrolyte pass through the sensing area, and the immersed volume of the particles replaces the electrolyte of the same volume, so that the resistance of the sensing area changes temporarily. This resistance change leads to the generation of corresponding current pulses or voltage pulses. By measuring the number and amplitude of the electric pulses and calculating by the computing device, information about the number of particles and the volume of each particle can be obtained; the sub-control system is connected to the sampling control mechanism, the pneumatic conveying system 2, the first control valve, the second control valve, and the computing device. The function of the sub-control system is to control the actions of the sampling control mechanism, the pneumatic conveying system 2, the first control valve, and the second control valve, and to receive and transmit the detection results obtained by the computing device.

[0038] In some embodiments of the present invention, the particle size detection device 7 further includes a stirring device 23, which is disposed in the detection pool 17 and connected to the sub-control system. The function of the stirring device 23 is to make the sample particles evenly distributed in the electrolyte to prevent detection deviation caused by uneven particle distribution.

[0039] In some embodiments of the present invention, the particle size detection device 7 further includes a liquid inlet pipe 24 and a liquid outlet pipe 25 respectively connected to the detection cell 17. A liquid inlet pump and a liquid inlet valve are provided on the liquid inlet pipe 24; a liquid outlet pump and a liquid outlet valve are provided on the liquid outlet pipe 25; the liquid inlet pump, the liquid outlet pump, the liquid inlet valve, and the liquid outlet valve are respectively connected to the sub-control system. The detection cell 17 of this device is connected to the liquid inlet pipe 24 and the liquid outlet pipe 25, and electrolyte can be added to the detection cell 17 after sampling. With the stirring of the stirring device 23, a suspension with uniform particle distribution can be obtained for particle size detection. After the detection, the liquid and particles in the detection cell 17 can be discharged through the liquid outlet pipe 25. When needed, the detection cell 17 can be cleaned by feeding liquid through the liquid inlet pipe 24 for the next detection. The particle size detection device 7 disclosed in the present invention, in cooperation with devices such as the sub-control system, can achieve multiple consecutive detections and real-time output of detection results.

[0040] In some embodiments of the present invention, the induction device 22 is a pulse resistance induction device 22 and / or a pulse current induction device 22.

[0041] In some embodiments of the present invention, a flap connection port is provided on one side of the sampling tube 9 opposite to the side where the sampling port is located, and the distance between the side where the sampling port of the sampling tube 9 is located and the side where the flap connection port is located is D; the sampling control mechanism includes a flap mechanism, and the flap mechanism includes a first flap 11, a second flap 12, a flap connection mechanism 13, and a flap driving device 14. The first flap 11 is arranged inside the sampling tube 9, and the length of the first flap 11 is L; the second flap 12 is arranged outside the sampling tube 9; the flap connection mechanism 13 is arranged at the flap connection port and is rotatably connected to the wall of the sampling tube 9. The upper ends of the first flap 11 and the second flap 12 are connected by the flap connection mechanism 13; the included angle between the first flap 11 and the second flap 12 is α, and L≥D / sinα; the flap driving device 14 is connected to the second flap 12. Preferably, the flap driving device 14 is a cylinder. When sampling is required, the second flap 12 is driven by the cylinder to approach the outer wall of the sampling tube 9. The second flap 12 drives the bottom end of the first flap 11 to approach the other side of the sampling tube 9 through the flap connection mechanism 13. At this time, the second flap 12 blocks the conveyance of particles in the particle conveyance system path. The particles are guided by the second flap 12 and enter the sampling port on the side wall of the sampling tube 9, and then enter the sample conveyance tube 10 to complete the sampling. It should be noted that when the first flap 11 contacts the inner wall of the sampling tube 9 on the side opposite to the flap connection port under the drive of the second flap 12, it is necessary to ensure that the contact point of the first flap 11 with the inner wall of the sampling tube 9 is downstream of the sampling port (here, downstream is relative to the particle conveyance direction in the production system). Most preferably, the sampling port is adjacent to the contact point of the first flap 11 with the inner wall of the sampling tube 9, so as to ensure that the particles can enter the sampling port under the guidance of the first flap 11 during sampling.

[0042] In some embodiments of the present invention, the flap connection mechanism 13 includes a connection shaft. The connection shaft is arranged inside the flap connection port and is rotatably connected to the sampling tube 9 at both ends; the upper ends of the first flap 11 and the second flap 12 are respectively fixedly connected to the connection shaft.

[0043] In some embodiments of the present invention, the pneumatic conveying system 2 includes a high-pressure gas system, a high-pressure gas pipe 15 connected to the high-pressure gas system, and a third control valve 16 arranged on the high-pressure gas pipe 15; an air inlet is provided on the side wall of the input end of the sample conveyance tube 10. The outlet end of the high-pressure gas pipe 15 is inclinedly connected to the air inlet on the sample conveyance tube 10 towards the middle section of the sample conveyance tube 10, so as to ensure that the high-pressure gas blows from the input end of the sample conveyance tube 10 to the output end of the sample conveyance tube 10, thereby realizing the pneumatic conveying of the particle sample; the third control valve 16 is connected to the sub-control system.

[0044] An electrolytic aluminum system with the described automatic particle sampling and detection device, comprising a fluorine-bearing alumina particle conveying pipeline 8, a feeding system, an electrolytic cell, and a master control system. The discharging end of the fluorine-bearing alumina particle conveying pipeline 8 is connected to the feeding system, the feeding system is connected to the electrolytic cell, and the master control system is respectively connected to the feeding system and the electrolytic cell. The sampling pipe 9 divides the fluorine-bearing alumina particle conveying pipeline 8 into two sections, and both ends of the sampling pipe 9 are respectively connected to the fluorine-bearing alumina particle conveying pipeline 8 at its two ends; the discharging end of the return pipeline 5 is connected to the fluorine-bearing alumina particle conveying pipeline 8; the diameter of the detection port is larger than the particle size of the fluorine-bearing alumina and smaller than twice the particle size of the fluorine-bearing alumina; the detection pool 17 contains electrolyte, and both the first electrode 20 and the second electrode 21 are immersed in the electrolyte; the sub-control system is connected to the master control system for transmitting the particle size detection result to the master control system.

[0045] A control method for the electrolytic aluminum system described above, comprising:

[0046] S1, primary sampling: The sub-control system sends a sampling instruction to the sampling control mechanism, and the sampling control mechanism controls to intercept part of the fluorine-bearing alumina particles in the fluorine-bearing alumina particle conveying pipeline 8 and enter the sample conveying pipe 10; meanwhile, the sub-control system controls to activate the pneumatic conveying system 2, and under the action of high-pressure gas, conveys the fluorine alumina particles that have entered the sample conveying pipe 10 to the mixing device 3, and closes the pneumatic conveying system 2 after sampling ends;

[0047] S2, mixing: The sub-control system controls the mixing device 3 to mix the fluorine alumina particles, and after mixing ends, the sub-control system controls the mixing device 3 to discharge materials to the sample bin 4;

[0048] S3, secondary sampling and return: The sub-control system controls to activate the pneumatic conveying system 2, and at the same time opens the first control valve and the second control valve, so that part of the fluorine-bearing alumina particles return from the return pipeline 5 to the fluorine-bearing alumina particle conveying pipeline 8, and another part of the fluorine-bearing alumina particles enter the detection pool 17 from the detection sampling pipe 6;

[0049] S4, particle size detection: The sub-control system controls to activate the circulation pump 19, so that the electrolyte containing fluorine alumina particles enters the circulation pipe 18 from the detection port of the circulation pipe 18. When the fluorine alumina particles pass through the detection port, a potential pulse is generated between the first electrode 20 and the second electrode 21, and the induction device 22 transmits the potential pulse signal to the calculation device. The calculation device calculates the particle size information of the fluorine alumina particles and transmits the particle size information to the master control device in real time;

[0050] S5, feeding control and electrolytic cell parameter regulation: The master control system adjusts the working parameters of the feeding system and the electrolytic cell in real time according to the particle size information of the fluorine alumina particles.

[0051] In some embodiments of the present invention, after the particle size detection is completed, the sub-control system controls the discharge of the electrolyte containing the fluorinated alumina particles in the detection cell 17, and then controls the injection of a new electrolyte into the detection cell 17.

[0052] In the particle automatic sampling and detection device disclosed by the present invention, a mixing device 3 and a detection sampling tube 6 are arranged in the particle size detection system, which can perform secondary mixing and secondary sampling on the samples taken by the sampling tube 9, further ensuring the randomness and reliability of sampling and improving the accuracy of detection. The present invention is provided with a return pipeline 5 behind the sample bin 4, which can recycle the remaining materials after sampling into the production system twice, avoiding waste of raw materials.

[0053] In the description of the present application, it should be noted that the orientation or positional relationship indicated by the terms "upper", "lower", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be construed as a limitation of the present application. In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0054] Unless otherwise clearly defined and limited, the terms "set" and "connect" 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 mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific situations.

[0055] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A particle automatic sampling and detection device, characterized in that: Including sampling device, pneumatic conveying system, particle size detection system, sub-control system, The sampling device comprises a sampling tube, a sampling control mechanism, and a sample delivery tube. The side wall of the sampling tube is provided with a sampling port, the sampling port is externally connected to the input end of the sample delivery tube, and the sampling control mechanism is arranged on the sampling tube; the pneumatic delivery system is connected to the sample delivery tube; The particle size detection system includes a mixing device, a sample bin, a return material pipeline, a detection sampling tube, and a particle size detection device. The feed inlet of the mixing device is connected to the output end of the sample delivery tube; the sample bin is connected to the discharge port of the mixing device, the sample bin is provided with a discharge port, the discharge port of the sample bin is respectively connected to the return pipe and the detection sampling tube, and the return pipe and the detection sampling tube are respectively provided with a first control valve and a second control valve; The particle size detection device comprises a detection pool, a circulation pipe, a circulation pump, an electrode system, a sensing device and a computing device, wherein the detection pool is connected to the discharge end of the detection sampling pipe; the circulation pipe comprises a first end and a second end, wherein the end of the first end of the circulation pipe is closed and arranged in the detection pool, a detection port is provided on the side wall of the first end of the circulation pipe, and a first electrode inlet is also provided on the circulation pipe; the second end of the circulation pipe is connected to the detection pool; the circulation pump is arranged on the circulation pipe; the electrode system comprises a first electrode and a second electrode, wherein the first electrode extends from the first electrode inlet into the circulation pipe and is arranged at the first end of the circulation pipe; the second electrode is arranged in the detection pool; the first electrode and the second electrode are located at different heights in the detection pool; the sensing device comprises an input end and an output end, wherein the input end of the sensing device is connected to the first electrode and the second electrode, and the output end of the sensing device is connected to the computing device; The sub-control system is connected with the sampling control mechanism, the pneumatic conveying system, the first control valve, the second control valve, and the computing device.

2. The automatic particle sampling and detection device according to claim 1, characterized in that: The particle size detection device further comprises a stirring device, which is arranged in the detection pool and connected to the sub-control system.

3. The automatic particle sampling and detection device according to claim 1, characterized in that: The particle size detection device also includes a liquid inlet pipe and a liquid outlet pipe respectively connected to the detection pool, the liquid inlet pipe is provided with a liquid inlet pump and a liquid inlet valve; the liquid outlet pipe is provided with a liquid outlet pump and a liquid outlet valve; the liquid inlet pump, liquid outlet pump, liquid inlet valve, and liquid outlet valve are respectively connected to the sub-control system.

4. The automatic particle sampling and detection device according to claim 1, characterized in that: The sensing device is a pulse resistance sensing device and / or a pulse current sensing device.

5. The automatic particle sampling and detection device according to claim 1, characterized in that: A flap connection port is provided on the sampling tube on a side opposite to the sampling port, and the distance between the sampling port side of the sampling tube and the flap connection port side is D; The sampling control mechanism includes a flap mechanism, which includes a first flap, a second flap, a flap connecting mechanism, and a flap driving device. The first flap is arranged inside the sampling tube, and the length of the first flap is L; the second flap is arranged outside the sampling tube; the flap connecting mechanism is arranged at the flap connecting port and is rotatably connected to the sampling tube wall, and the upper end of the first flap and the upper end of the second flap are connected through the flap connecting mechanism; the angle between the first flap and the second flap is α, L≥D / sinα; the flap driving device is connected to the second flap.

6. The automatic particle sampling and detection device according to claim 4, characterized in that: The flap connection mechanism comprises a connection shaft, which is arranged in the flap connection port and has two ends respectively connected to the sampling tube for rotation; the upper end of the first flap and the upper end of the second flap are respectively fixedly connected to the connection shaft.

7. The automatic particle sampling and detection device according to claim 1, characterized in that: The pneumatic conveying system includes a high-pressure gas system, a high-pressure gas pipe connected to the high-pressure gas system, and a third control valve arranged on the high-pressure gas pipe; an air inlet is arranged on the side wall of the input end of the sample delivery pipe, and the outlet end of the high-pressure gas pipe is inclined toward the middle section of the sample delivery pipe and is connected obliquely to the air inlet on the sample delivery pipe; the third control valve is connected to the sub-control system.

8. An electrolytic aluminum system with the automatic particle sampling and detection device according to any one of claims 1 to 6, comprising a fluorine-containing aluminum oxide conveying pipeline, a feeding system, an electrolytic cell, and a master control system, wherein the discharge end of the fluorine-containing aluminum oxide conveying pipeline is connected to the feeding system, the feeding system is connected to the electrolytic cell, and the master control system is connected to the feeding system and the electrolytic cell, respectively, characterized in that: The sampling tube divides the fluorine-carrying alumina conveying pipeline into two sections, and the two ends of the sampling tube are respectively connected to the fluorine-carrying alumina conveying pipelines located at the two ends thereof; The discharge end of the return pipe is connected to the fluorine-loaded alumina conveying pipeline; The diameter of the detection port is larger than the particle size of the fluorine-carrying aluminum oxide and smaller than 2 times the particle size of the fluorine-carrying aluminum oxide; the detection cell carries an electrolyte, and the first electrode and the second electrode are both immersed in the electrolyte; The sub-control system is connected to the main control system and is used to transmit the particle size detection result to the main control system.

9. A control method for an aluminum electrolysis system according to claim 8, characterized in that: include: S1, one-time sampling: the sub-control system sends a sampling instruction to the sampling control mechanism, and the sampling control mechanism controls the interception of part of the fluorine-carrying aluminum oxide particles in the fluorine-carrying aluminum oxide conveying pipeline to enter the sample conveying pipe; at the same time, the sub-control system controls the opening of the pneumatic conveying system, and under the action of high-pressure gas, the fluorine-carrying aluminum oxide particles entering the sample conveying pipe are conveyed to the mixing device, and the pneumatic conveying system is closed after the sampling is completed; S2, mixing: the sub-control system controls the mixing device to mix the aluminum oxyfluoride particles. After the mixing is completed, the sub-control system controls the mixing device to discharge the material into the sample bin; S3, secondary sampling and material return: the sub-control system controls the opening of the pneumatic conveying system, and simultaneously opens the first control valve and the second control valve, so that part of the fluorine-containing alumina particles return from the material return pipeline to the fluorine-containing alumina conveying pipeline, and another part of the fluorine-containing alumina particles enter the detection pool from the detection sampling tube; S4, particle size detection: the sub-control system controls to start the circulation pump, so that the electrolyte containing the fluorinated aluminum oxide particles enters the circulation pipe from the detection port of the circulation pipe, and when the fluorinated aluminum oxide particles pass through the detection port, a potential pulse is generated between the first electrode and the second electrode, and the sensing device transmits the potential pulse signal to the calculation device, and the calculation device calculates the particle size information of the fluorinated aluminum oxide particles and transmits the particle size information to the master control device in real time; S5, feeding control and electrolytic cell parameter regulation: the master control system regulates the working parameters of the feeding system and the electrolytic cell in real time according to the particle size information of the aluminum oxyfluoride particles.

10. The control method of an electrolytic aluminum system according to claim 9, characterized in that: After the particle size test is completed, the sub-control system controls the discharge of the electrolyte containing the fluorine-loaded aluminum oxide particles in the test pool, and then controls the injection of new electrolyte into the test pool.

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