A monitor for monitoring static electricity of powder in a horizontal pipe.

Abstract

This invention provides a monitor for monitoring the static electricity of powder in a horizontal pipe, comprising a cylindrical body with an inner cavity connected to the horizontal pipe. The cylindrical body includes an outer cylinder and an inner cylinder made of metal and nested together, and an insulating cylinder disposed between the outer and inner cylinders. An opening communicating with the inner cavity is provided on the outer wall of the pipe; a piston disposed in a sealed manner within the inner cavity; a motion generating device connected to the piston, the motion generating device being able to control the movement of the piston to open or close the opening; and a measuring device for detecting the potential difference between the outer and inner cylinders. The powder in the horizontal pipe falls into the inner cavity under the action of gravity when the piston is in a first position, thereby generating a potential difference between the outer and inner cylinders that can be detected by the measuring device. The monitor for monitoring the static electricity of powder in a horizontal pipe of this invention has a simple structure, small error, and is applicable to horizontal pipes.

Description

Technical Field

[0001] This invention relates to a monitor for monitoring the static electricity of powder in a horizontal pipe. Background Technology

[0002] In industrial production processes, polymer powders such as polyolefins, polyesters, and polyvinyl alcohol are typically transported, mixed, and packaged using pneumatic conveying systems. However, these powders are prone to friction with the pipelines during transport, leading to electrical discharges. Furthermore, since many of these powders are flammable, they can easily cause flash explosions when exposed to electrical discharges. Therefore, ion wind electrostatic eliminators should be used during powder transport to prevent cone-shaped discharges on the surface of the material pile or lightning-shaped discharges from dust clouds and metal protrusions.

[0003] However, during the conveying of powder and granular materials, extremely fine dust particles inevitably carry a charge. Research shows that the polarity of the charge on the granules during powder conveying is related to the particle size; even materials with the same composition will carry charges of different polarities due to differences in particle size. Therefore, when using ion wind eliminators to eliminate static electricity in materials, a bipolar static eliminator capable of simultaneously generating positive and negative ion winds must be used to neutralize and eliminate the static electricity.

[0004] Currently, DC-type ion-wind electrostatic eliminators are commonly used to eliminate static electricity in powder within pneumatic conveying pipelines. When using an electrostatic eliminator in a silo device, the ion wind generates corona discharge through a discharge needle connected to a high-voltage generator module, ionizing air molecules. The positive and negative ions are then blown into the pipeline by the air supply system, thus eliminating the static charge on the powder. However, DC-type ion-wind electrostatic eliminators require predicting the charge and polarity of the particles within the pipeline and adjusting the voltage and polarity of the high-voltage generator module accordingly to prevent "reverse charging" of the particles. Therefore, ion-wind electrostatic eliminators need to use an electrostatic monitor to detect the charge and polarity of the powder within the pipeline in real time.

[0005] When pneumatically conveying chemical materials, the charge on the material is affected by the mass flow rate and the pneumatic conveying velocity; the charge varies at different mass flow rates. Furthermore, the particle concentration distribution within the pipeline during pneumatic conveying makes it difficult to directly measure the charge or charge-to-mass ratio parameters using induction methods. Additionally, current ion-wind electrostatic eliminators for silos are mainly installed at the silo inlet, requiring a certain height in the inlet pipe to accommodate the eliminator. However, in chemical material production plants, silo inlet pipes are often horizontal or very short vertical pipes. Existing powder electrostatic monitoring devices require the sampler to be inserted deep into the pipe to collect samples. Therefore, existing monitors can only be installed in vertical pipe sections and are not suitable for horizontal pipes. Summary of the Invention

[0006] To address the technical problems described above, this invention aims to provide a monitor for monitoring the static electricity of powder in a horizontal pipe. The monitor of this invention has a simple structure, small detection error, and is applicable to horizontal pipes.

[0007] According to the present invention, a monitor for monitoring the static electricity of powder in a horizontal pipe is provided, comprising: a cylindrical body with an inner cavity connected to the horizontal pipe, the cylindrical body comprising an outer cylinder and an inner cylinder made of metal and sleeved together, and an insulating cylinder disposed between the outer cylinder and the inner cylinder, the inner cavity being connected to the pipe through an opening disposed on the outer wall of the pipe; a piston disposed in a sealed manner within the inner cavity; a motion generating device connected to the piston, the motion generating device being capable of controlling the movement of the piston such that the piston has a first position of opening the opening to allow powder in the horizontal pipe to enter the inner cavity, and a second position of closing the opening; and a measuring device for detecting the potential difference between the outer cylinder and the inner cylinder.

[0008] The cylinder is positioned radially below the horizontal pipe, and the powder inside the horizontal pipe can fall into the inner cavity under gravity when the piston is in the first position, thereby generating a potential difference between the outer and inner cylinders that can be detected by a measuring device.

[0009] In a preferred embodiment, the piston has the same curvature as the pipe and the same shape as the opening, such that when the piston is in the second position, powder on the piston can be fed into the horizontal pipe.

[0010] In a preferred embodiment, the piston has the same size as the opening, such that when the piston is in the second position, it fits exactly inside the opening.

[0011] In a preferred embodiment, a bottom plate is provided at the bottom of the cylinder, and an insulating layer is also provided on the side of the bottom plate near the inner cavity.

[0012] In a preferred embodiment, the insulating layer and the insulating cylinder are made of polytetrafluoroethylene, the wall thickness of the insulating cylinder is set to 3mm-4mm, and the thickness of the insulating layer is set to 6mm-7mm.

[0013] In a preferred embodiment, a through hole communicating with the inner cavity is provided on the base plate, and the motion generating device is connected to the piston through a connecting rod passing through the through hole.

[0014] In a preferred embodiment, the potential difference measuring device includes a signal acquisition processor connected to the cylinder and a remote data processor connected to the signal acquisition processor.

[0015] In a preferred embodiment, the signal acquisition processor is connected to the inner cylinder via the first core of a double-core shielded wire, and the second core of the double-core shielded wire is connected to the outer cylinder.

[0016] In a preferred embodiment, the piston is made of an antistatic material, and the motion generating device is a direct-acting cylinder.

[0017] In a preferred embodiment, the monitor for monitoring the static electricity of powder in a horizontal pipe further includes a separate tube with the same diameter as the pipe, the tube being connected to the pipe through an opening, and the tube being horizontally connected to the pipe in a detachable manner. Attached Figure Description

[0018] The present invention will now be described with reference to the accompanying drawings.

[0019] Figure 1 A schematic diagram of a monitor for monitoring static electricity of powder in a horizontal pipe according to an embodiment of the present invention is shown.

[0020] In this application, all drawings are schematic and are used only to illustrate the principles of the invention, and are not drawn to scale. Detailed Implementation

[0021] The invention will now be described with reference to the accompanying drawings.

[0022] Figure 1 A monitor 100 for monitoring static electricity of powder in a horizontal pipe, according to an embodiment of the present invention, is shown. Figure 1 As shown, the monitor 100 includes a cylindrical body 10. The cylindrical body 10 includes an outer cylindrical body 12 and an inner cylindrical body 14, both made of metal. The outer cylindrical body 12 and the inner cylindrical body 14 are constructed as concentric cylindrical or concentric square tubes nested together. An inner cavity 20 is defined within the cylindrical body 10. An insulating cylinder 16, made of insulating material, is also disposed between the outer cylindrical body 12 and the inner cylindrical body 14, effectively isolating them. The outer cylindrical body 12 is grounded via a wire, thus forming a Faraday cylinder with the cylindrical body 10.

[0023] like Figure 1As shown, the cylindrical body 10 is connected to the horizontal pipe 30. Specifically, an opening 32 penetrating the outer wall of the horizontal pipe 30 is provided on any section of the pipe body in the axial middle of the horizontal pipe 30. The cylindrical body 10 is fixed at the opening 32, and the inner cavity 20 is connected to the transport channel 35 inside the horizontal pipe 30. At the same time, the cylindrical body 10 is connected to the lower axial direction of the horizontal pipe 30. Thus, when the powder in the transport channel 35 passes through the opening 32, it will fall into the inner cavity 20 by gravity through the opening 32.

[0024] Meanwhile, a piston 25 and a motion generating device 26 connected to the piston 25 are also provided inside the inner cavity 20. The piston 25 can move vertically between the horizontal pipe 30 and the bottom plate 18 of the cylinder 10 within the inner cavity 20 under the action of the motion generating device 26. Furthermore, during the movement of the piston 25, when the piston 25 is in the first position abutting against the horizontal pipe 30, the piston 25 can cover and block the opening 32, cutting off the connection between the transport channel 35 and the inner cavity 20. When the piston 25 is in the second position abutting against the bottom plate 18 of the cylinder, the transport channel 35 remains connected to the inner cavity 20.

[0025] Therefore, when the piston 25 is in the second position, the charged powder passing through the opening 32 will fall into the inner cavity 20 under the action of gravity until it fills the entire inner cavity 20, generating a potential difference U between the outer cylinder 12 and the inner cylinder 14. It is easy to understand that those skilled in the art can use the potential difference U and well-known simple calculations to determine the amount of charge and the charge-to-mass ratio of the powder in the inner cavity 20, i.e., the electrostatic charge of the powder.

[0026] In a preferred embodiment, the piston 25 is made of an antistatic material. This arrangement prevents the piston 25 from generating static electricity or from becoming electrically charged through friction with the cylinder 10 during movement, thus avoiding interference with the measurement of the potential difference U.

[0027] like Figure 1 As shown, the monitor 100 for monitoring the static electricity of powder in a horizontal pipe also includes a measuring device 40 for detecting the potential difference between the outer and inner cylinders. The measuring device 40 can be, for example, an electrometer, which is simple in structure and easy to operate. The electrometer can be used to determine the potential difference U between the outer cylinder 12 and the inner cylinder 14. Since the capacitance C of the electrometer is known, the total charge of the powder in the inner cavity 20 is Q = U·C. When the powder fills the entire inner cavity 20, the volume of the powder is equal to the volume V of the inner cavity 20. Simultaneously, the bulk density ρ of the powder is an inherent property, so the mass of the powder in the inner cavity 20 is m = ρ·V. Therefore, the charge-to-mass ratio of the powder is R = Q / m.

[0028] In a preferred embodiment, to improve the accuracy of the measuring device 40, the measuring device 40 can be configured as a signal acquisition processor 42, which may be, for example, a charge transmitter. Measuring the total charge Q of the powder within the inner cavity 20 using the charge transmitter can further reduce errors caused by manual measurement. Furthermore, a remote data processor (not shown) is also connected to the signal acquisition processor 42. The remote data processor may be, for example, a petrochemical pneumatic conveying PLC system cabinet. The remote data processor can transmit the measured data to a computer terminal in the form of digital signals, thereby obtaining more accurate measurement data.

[0029] In a preferred embodiment, the signal acquisition processor 42 is connected to the cylinder 10 via a dual-core shielded cable. Specifically, the first core of the dual-core shielded cable connects the inner cylinder 14 and the signal acquisition processor 42, while the second core is directly and fixedly connected to the outer cylinder 12 and grounded through the outer cylinder 12. The dual-core shielded cable is used to shield against electromagnetic interference during data acquisition and processing, further improving the accuracy of data acquisition.

[0030] like Figure 1 As shown, the piston 25 is configured to have the same curvature as the horizontal pipe 30 and the same shape as the opening 32. Thus, when the piston 25 is in the second position, it can feed the powder on its surface into the transport channel 35 for continued transport, avoiding resource waste caused by inspection.

[0031] Meanwhile, the piston 25 has the same dimensions as the opening 32, so that when the piston 25 is in the second position, it fits perfectly inside the opening 32. This arrangement ensures that the piston 25 can properly close the opening 32 while allowing the powder on the piston 25 to completely enter the transport channel 35. This ensures that the inner cavity 20 remains empty after testing, preventing powder residue from affecting subsequent tests and guaranteeing the accuracy of multiple test results.

[0032] like Figure 1 As shown, in a preferred embodiment, the motion generating device 26 is configured as a direct-acting cylinder. The direct-acting cylinder can perform cyclical motion within its stroke range, thereby controlling the piston to perform cyclical motion within the inner cavity 20, thus enabling multiple measurements. The detection frequency of the monitor 100 can be controlled by adjusting the motion frequency of the direct-acting cylinder. Simultaneously, the direct-acting cylinder allows for convenient adjustment of its stroke, making it suitable for cylinders 10 of different heights.

[0033] like Figure 1As shown, a base plate 18 is also connected to the bottom of the cylinder 10. An insulating layer 50 is also provided on the side of the base plate 18 near the inner cavity 20. The insulating layer 50 is used to further improve the sealing level of the cylinder 10 and prevent charge leakage from affecting the detection structure.

[0034] Furthermore, both the insulating layer 50 and the insulating cylinder 16 are made of tetrafluoroethylene, which has high insulating properties. The thickness of the insulating layer 50 is set to 6mm-7mm, and the wall thickness of the insulating cylinder 16 is set to 3mm-4mm. This ensures that the insulating layer 50 and the insulating cylinder 16 have good charge-impeding effects, improving the detection accuracy of the monitor 100.

[0035] like Figure 1 As shown, the motion generating device 26 is located on the side of the base plate 18 away from the inner cavity 20. A through hole 19 is provided on the base plate 18 of the cylinder 10, and the motion generating device 26 is connected to the piston 25 through a connecting rod 28 passing through the through hole 19.

[0036] In a preferred embodiment, the monitor 100 for monitoring the static electricity of powder in the horizontal pipe further includes a separate tube (not shown) with the same diameter as the horizontal pipe 30, and the cylindrical body 10 is connected to the tube. The tube is detachably connected to the horizontal pipe 30, for example, by a flange connection or a coupling connection, so that the powder in the horizontal pipe 30 can pass through the tube with the same motion state.

[0037] It is easy to understand that the mass-to-charge ratio of the powder inside the tube can be indirectly determined by measuring the mass-to-charge ratio of the powder passing through the horizontal pipe 30. This design avoids openings in the horizontal pipe 30, preventing damage to it. Furthermore, the tube can be freely connected to any position within the horizontal pipe 30 as needed, improving the flexibility of the inspection.

[0038] The following is a brief description of the operation of the monitor 100 for monitoring the static electricity of powder in a horizontal pipe according to the present invention.

[0039] The detector 100 of the present invention for monitoring static electricity of powder in a horizontal pipe is used to detect the charge of charged powder. During the detection process, the motion generating device 26 is first turned on, and the stroke and motion frequency of the motion generating device 26 are set according to the actual detection needs, so that the motion generating device 26 drives the piston 25 to perform periodic motion.

[0040] When the piston 25 moves to the second position where it abuts against the bottom plate 18 of the cylinder, the transport channel 35 remains connected to the inner cavity 20. Under the influence of gravity, the powder in the transport channel 35 falls into the inner cavity 20 through the opening 32, filling the entire inner cavity 20 and generating a potential difference U between the outer cylinder 12 and the inner cylinder 14 of the cylinder 10. At this time, the signal acquisition processor 42 can transmit the charge and potential difference data of the cylinder 10 to a remote data processor via wires, thereby obtaining real-time detection data.

[0041] When the piston 25 moves to the first position where it abuts against the horizontal pipe 30, all the powder inside the cylinder 10 is returned to the transport channel 35, and at this time, the potential difference U between the entire outer cylinder 12 and the inner cylinder 14 is zero. At this point, one detection cycle is completed.

[0042] The movement frequency of the piston 25 can be controlled by adjusting the movement frequency of the motion generating device 26, thereby adjusting the detection frequency of the monitor 100 according to actual needs.

[0043] Finally, it should be noted that the above description is merely a preferred embodiment of the present invention and does not constitute any limitation on the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A monitor (100) for monitoring electrostatics of a powder in a horizontal pipe, characterized in that, include: A cylindrical body (10) with an inner cavity (20) is connected to a horizontal pipe (30). The cylindrical body includes an outer cylinder (12) and an inner cylinder (14) made of metal and fitted together, and an insulating cylinder (16) disposed between the outer cylinder and the inner cylinder. The inner cavity is connected to the horizontal pipe through an opening (32) disposed on the outer wall of the horizontal pipe. A piston (25) is provided in a sealed manner within the inner cavity; A motion generating device (26) connected to the piston controls the piston's movement, allowing it to have a first position where the opening is open to allow powder from the horizontal pipe to enter the inner cavity, and a second position where the opening is closed. The piston has the same curvature as the horizontal pipe, and its size and shape are the same as the opening, so that when the piston is in the second position, it fits precisely within the opening, and when the piston reaches the second position, it can deliver the powder on the piston into the entire horizontal pipe, thereby keeping the inner cavity empty. A measuring device (40) for detecting the potential difference between the outer cylinder and the inner cylinder. The cylinder is positioned radially below the horizontal pipe, and the powder inside the horizontal pipe can fall into the inner cavity under gravity when the piston is in the first position, thereby generating a potential difference between the outer and inner cylinders that can be detected by a measuring device.

2. The monitor (100) for monitoring static electricity of powder in a horizontal pipe according to claim 1, characterized in that, A bottom plate (18) is provided at the bottom of the cylinder, and an insulating layer (50) is also provided on the side of the bottom plate near the inner cavity.

3. The monitor (100) for monitoring static electricity of powder in a horizontal pipe according to claim 2, characterized in that, Both the insulating layer and the insulating cylinder are made of polytetrafluoroethylene. The wall thickness of the insulating cylinder is set to 3mm-4mm, and the thickness of the insulating layer is set to 6mm-7mm.

4. The monitor (100) for monitoring static electricity of powder in a horizontal pipe according to claim 2, characterized in that, A through hole (19) communicating with the inner cavity is provided on the base plate. The motion generating device is located on the side of the base plate away from the inner cavity and is connected to the piston through a connecting rod (28) passing through the through hole.

5. The monitor (100) for monitoring static electricity of powder in a horizontal pipe according to claim 1, characterized in that, The measuring device includes a signal acquisition processor (42) connected to the cylinder, and a remote data processor connected to the signal acquisition processor.

6. The monitor (100) for monitoring static electricity of powder in a horizontal pipe according to claim 5, wherein the signal acquisition processor is connected to the inner cylinder via the first core of a double-core shielded wire. The second core of the dual-core shielded wire is connected to the outer cylinder.

7. The monitor (100) for monitoring static electricity of powder in a horizontal pipe according to claim 1, characterized in that, The piston is made of antistatic material, and the motion generating device is a direct-acting cylinder.

8. The monitor (100) for monitoring static electricity of powder in a horizontal pipe according to claim 1, characterized in that, It also includes a separate pipe body with the same diameter as the horizontal pipe, the cylindrical body being connected to the pipe body through an opening, and the pipe body being horizontally connected to the pipe body in a detachable manner.

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