Overload protection mechanism and material separation device

Abstract

The utility model provides an overload protection mechanism and a material separation device. The overload protection mechanism comprises a PLC; the horizontal screw centrifuge is electrically connected with the PLC; the PLC comprises a measuring module and a comparator, the measuring module is used for collecting the running current of the horizontal screw centrifuge, and the comparator is used for comparing the running current with a current threshold value and outputting a level signal used for reducing the rotating speed of the feeding pump when the running current reaches the current threshold value. Serious potential safety hazards caused by heating of slurry due to blockage when the horizontal screw centrifuge rotates at a high speed can be avoided to the maximum extent. And continuous production and safe operation are ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of chemical engineering, and in particular, to an overload protection mechanism and a horizontal screw centrifuge assembly. Background Art

[0002] Chemical enterprises widely use horizontal screw centrifuges and feed pump devices for material separation work. The material and alcohol are separated by the horizontal screw centrifuge under high-speed rotation. The material is dried and pulverized to obtain the corresponding product, and the alcohol is evaporated and condensed for reuse. The feed pump is used to transport the material to be separated to the horizontal screw centrifuge.

[0003] Currently, a sequential control start interlock control method of a horizontal screw centrifuge (star-delta control) and a feed pump (direct control) is adopted. In the actual use process, due to different materials or blockage of the horizontal screw centrifuge, the operating current of the horizontal screw centrifuge changes greatly, and overload (current) situations often occur, resulting in equipment overload protection, damage, and material blockage. At the same time, when the horizontal screw centrifuge is running at high speed, blockage causes the material to heat up, and equipment damage and sparking may cause alcohol combustion and explosion, which has serious safety hazards and also affects the safe, stable, and continuous operation of the device. Summary of the Invention

[0004] In view of this, the purpose of the embodiments of the present application is to provide an overload protection mechanism that can solve the problem of safety hazards of the horizontal screw centrifuge.

[0005] To achieve the above technical purpose, the technical solution adopted in the present application is as follows:

[0006] In a first aspect, an overload protection mechanism provided by an embodiment of the present application includes:

[0007] PLC;

[0008] A horizontal screw centrifuge electrically connected to the PLC;

[0009] The PLC includes a measurement module and a comparator. The measurement module is used to collect the operating current of the horizontal screw centrifuge, and the comparator is used to compare the operating current with a current threshold and output a level signal for reducing the rotation speed of the feed pump when the operating current reaches the current threshold.

[0010] Further, it further includes a first frequency converter electrically connected to both the PLC and the horizontal screw centrifuge, which is used to emit a first analog current after receiving the level signal;

[0011] The PLC is used to control the feed pump to reduce the rotation speed after receiving the first analog current.

[0012] Further, the PLC further includes a PID controller, which is configured to adjust the first analog current to a second analog current after receiving the first analog current;

[0013] The overload protection mechanism further includes a second frequency converter, which is electrically connected to both the PLC and the feed pump, and is configured to reduce the input current of the feed pump and decrease the rotational speed of the feed pump after receiving the second analog current.

[0014] Further, the measurement module is a sampling circuit.

[0015] Further, an alarm is further included, which is electrically connected to the PLC and is configured to give an alarm after receiving the level signal.

[0016] In a second aspect, an embodiment of the present application further provides a material separation device, which includes a horizontal screw centrifuge and a feed pump, and further includes the above-mentioned overload protection mechanism.

[0017] The invention adopting the above technical solution has the following advantages:

[0018] In the technical solution provided by the present application, when the operating current of the horizontal screw centrifuge reaches the current threshold, a level signal for reducing the rotational speed of the feed pump is output, the rotational speed of the feed pump is reduced, the feed rate of the feed pump is controlled, effectively avoiding the blockage of the horizontal screw centrifuge caused by the inability to automatically control the feed rate, reducing the load of the horizontal screw centrifuge, thereby maximizing the elimination of serious safety hazards caused by the slurry heating due to blockage during the high-speed rotation of the horizontal screw centrifuge, and ensuring continuous and safe production operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The present application can be further illustrated by the non-limiting embodiments given in the drawings. It should be understood that the following drawings only show some embodiments of the present application, and thus should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0020] Figure 1 Structural diagram of the overload protection mechanism provided for Embodiment 1.

[0021] Figure 2 Schematic diagram of the connection manner of the PLC, the first frequency converter and the second frequency converter provided for Embodiment 1.

[0022] Figure 3 Structural diagram of the overload protection mechanism provided for Embodiment 2.

[0023] Reference numerals: 1 - PLC; 11 - PID controller; 12 - measurement module; 13 - comparator; 2 - first frequency converter; 3 - horizontal screw centrifuge; 4 - second frequency converter; 5 - horizontal screw centrifuge; 6 - alarm. Specific Embodiments

[0024] The following will describe the present application in detail with reference to the accompanying drawings and specific embodiments. It should be noted that in the description of the drawings or the specification, similar or identical parts are denoted by the same reference numerals, and the implementation manners not shown or described in the drawings are forms known to those of ordinary skill in the art. In the description of the present application, the terms "first", "second", etc. are only used for distinguishing descriptions and cannot be construed as indicating or implying relative importance.

[0025] Embodiment 1

[0026] This embodiment provides an overload protection mechanism for solving the problems raised in the background art. As Figure 1 and Figure 2 shown, it includes a PLC 1, where the horizontal screw centrifuge 3 and the feed pump 5 are both electrically connected to the PLC 1. The PLC 1 includes a measurement module 12 and a comparator 13. The measurement module 12 is used to collect the operating current of the horizontal screw centrifuge, and the comparator 13 is used to compare the operating current with the current threshold, and when the operating current reaches the current threshold, output a level signal for reducing the rotational speed of the feed pump 5.

[0027] By comparing the horizontal screw centrifuge 3 with the current threshold, when the operating current reaches the current threshold, it indicates that the load of the horizontal screw centrifuge 3 is relatively large. The comparator 13 outputs a level signal, and the staff can reduce the rotational speed of the feed pump 5 according to the reminder of the level signal.

[0028] This embodiment further includes a first frequency converter 2 and a second frequency converter 4. The first frequency converter 2 is electrically connected to the horizontal screw centrifuge 3 for controlling the current value input to the horizontal screw centrifuge 3. The second frequency converter 4 is electrically connected to the feed pump 5 for controlling the current value of the horizontal screw centrifuge 5, and further controlling the rotational speed of the feed pump 3.

[0029] The first frequency converter 2 is configured to emit a first analog current after receiving the level signal. After the PLC 1 receives the first analog current, it controls the feed pump to reduce the rotational speed and reduce the feeding amount of the feed pump 3.

[0030] The PLC 1 includes a PID controller 11 for adjusting the first analog current to a second analog current after receiving the first analog current.

[0031] The overload protection mechanism further includes a second frequency converter 4, which is electrically connected to both the PLC 1 and the feed pump 4, and is used to reduce the input current of the feed pump and reduce the rotational speed of the feed pump after receiving the second analog current.

[0032] In this embodiment, the measurement module 12 is a sampling circuit.

[0033] The implementation manner of the overload protection mechanism is as follows: The measurement module 12 collects the operating current of the horizontal scroll centrifuge 5 in real time. After the collection, the comparator 13 compares the operating current with the current threshold. When the operating current reaches the preset current threshold (the current threshold can be set to the maximum safe current of the horizontal scroll centrifuge), the comparator 13 sends out a level signal. After receiving the level signal, the first frequency converter 2 generates a first analog current and transmits it to the PLC 1. The PID controller 11 adjusts the first analog current to a second analog current, and then transmits the second analog current to the second frequency converter 4. After receiving the second analog current, the second frequency converter 4 adjusts the current input to the feed pump 5, reduces the rotational speed of the feed pump 5, and decreases the feeding amount of the feed pump 5 to the horizontal scroll centrifuge 3 until the operating current does not reach the current threshold.

[0034] In this embodiment, both the first analog current and the second analog current are 20 mA.

[0035] Embodiment 2

[0036] This embodiment includes the PLC 1. As Figure 3 shown, the horizontal scroll centrifuge 3 is electrically connected to the PLC 1. The PLC 1 includes a measurement module 12 and a comparator 13. The measurement module 12 is used to collect the operating current of the horizontal scroll centrifuge 3, and the comparator 13 is used to compare the operating current with the current threshold. When the operating current reaches the current threshold, it sends out a level signal. The alarm 6 is electrically connected to the PLC 1 and is used to give an alarm when receiving the level signal. The alarm method is not limited to sound, flashing, etc.

[0037] Embodiment 3

[0038] This embodiment provides a material separation device, which includes a horizontal scroll centrifuge 5 and a feed pump 3, and also includes the overload protection mechanism described in Embodiment 1 or 2.

[0039] The above are only the embodiments of the present application and are not used to limit the protection scope of the present application. For those skilled in the art, various changes and modifications can be made to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An overload protection mechanism, characterized in that: include: PLC; A decanter centrifuge electrically connected to the PLC; The PLC includes a measuring module and a comparator. The measuring module is used to collect the operating current of the horizontal screw centrifuge. The comparator is used to compare the operating current with a current threshold and output a level signal for reducing the rotation speed of a feed pump when the operating current reaches the current threshold.

2. The overload protection mechanism according to claim 1, characterized in that: It also includes a first frequency converter electrically connected to the PLC and the horizontal screw centrifuge, and is used to send a first analog current after receiving the level signal; The PLC is used to control the feed pump to reduce the rotation speed after receiving the first analog current.

3. The overload protection mechanism according to claim 2, characterized in that: The PLC further comprises a PID controller, which is used to adjust the first analog current to a second analog current after receiving the first analog current; The overload protection mechanism also includes a second frequency converter, which is electrically connected to the PLC and the feeding pump, and is used to reduce the input current of the feeding pump and the rotation speed of the feeding pump after receiving the second analog current.

4. The overload protection mechanism according to claim 1, characterized in that: The measuring module is a sampling circuit.

5. The overload protection mechanism according to claim 1, characterized in that: It also includes an alarm, which is electrically connected to the PLC and is used to issue an alarm after receiving the level signal.

6. A material separation device, comprising a horizontal screw centrifuge and a feed pump, characterized in that: It also includes the overload protection mechanism described in any one of claims 1-5.

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