Press system and automatic control method of press system

Abstract

The application provides a kind of pressing system and the automatic control method of pressing system, belong to filter press control technical field.System includes: hopper, for storing material to be pressed;Filter press is connected hopper by material conveying mechanism, for material is pressed;Conveyor is arranged below the discharge port of filter press, for conveying the material after pressing, weighing mechanism is provided on the conveyor, for obtaining the quality of material after pressing on the conveyor;Data acquisition sensor group is used to collect the hopper liquid level of hopper, and collect the feed concentration, feed flow, feed pressure, filtrate water flow of filter press;Controller is used to control the start-stop of material conveying mechanism, filter press and conveyor based on hopper liquid level, feed concentration, feed flow, feed pressure, filtrate water flow and the quality of material after pressing.The application realizes automatic control of pressing by obtaining process parameters of pressing system, the control method is simple, and reduces the cost of pressing.

Description

Technical Field

[0001] This invention relates to the field of filter press control technology, and more specifically to a pressing system and an automatic control method for the pressing system. Background Technology

[0002] A filter press is a filtration device used to separate solids and liquids from materials. Currently, filter presses used in coal preparation plants are primarily single-unit automated equipment, with their process flow mainly divided into three stages: feeding, pressing, and discharging. Process control and the interlocking control of upstream and downstream equipment typically require on-site operation by a worker, as detailed below: The feeding process requires the operator to determine when to start and stop the feeding pump based on the liquid level in the feeding tank, and to manually set the feeding time based on the feeding pressure and the condition of the filtrate water.

[0003] The pressing process requires the operator to manually set the pressing time based on the filtrate water content.

[0004] The unloading process requires operators to manually start and stop the conveyor downstream of the filter press and monitor the adhesion of the filter cloth in real time.

[0005] Therefore, the control of filter presses has the following disadvantages: the manual control method results in low control efficiency, high labor costs, and a large amount of on-site work. Summary of the Invention

[0006] The purpose of this invention is to provide a pressing system and an automatic control method for the pressing system, so as to solve the problems of low control efficiency, high labor costs, and large workload of manual control methods.

[0007] To achieve the above objectives, embodiments of the present invention provide a pressing system, the system comprising: A material hopper is used to store materials to be pressed. A filter press, wherein the feed inlet of the filter press is connected to the material barrel through a material conveying mechanism, and the filter press is used to press materials; A conveyor is installed below the discharge port of the filter press for conveying the pressed material. The conveyor is equipped with a weighing mechanism to obtain the mass of the pressed material. The data acquisition sensor group is used to collect the liquid level in the material tank, as well as the feed concentration, feed flow rate, feed pressure, and filtrate flow rate of the filter press. The controller, connected to the data acquisition sensor group, the weighing mechanism, the material conveying mechanism, and the filter press, is used to control the start and stop of the material conveying mechanism, the filter press, and the conveyor based on the liquid level in the hopper, the feed concentration, the feed flow rate, the feed pressure, the filtrate flow rate, and the mass of the pressed material.

[0008] Optionally, the material conveying mechanism is a feed pump; The weighing mechanism is a belt scale.

[0009] Optionally, the data acquisition sensor group includes: A level gauge is installed on the material tank to detect the liquid level in the tank. A feed flow meter is installed at the feed inlet of the filter press to detect the feed flow rate of the filter press. A feed concentration meter is installed at the feed inlet of the filter press to detect the feed concentration of the filter press. A feed pressure gauge is installed at the feed inlet of the filter press to detect the feed pressure of the filter press. A filtrate flow meter is installed at the outlet of the filter press to detect the filtrate flow rate of the filter press.

[0010] Optionally, the controller is a DCS controller; The system also includes: An industrial computer and a mobile control terminal are respectively connected to the controller. The industrial computer and the mobile control terminal are used to generate corresponding control commands based on external input signals and send them to the controller. The controller is also used to control the start and stop of the material conveying mechanism, the filter press and the conveyor based on the control commands.

[0011] A second aspect of the present invention also provides an automatic control method for a pressing system, applied to the above-described pressing system, the method comprising: Obtain the liquid level and feed pressure in the material tank; If the liquid level in the hopper is greater than the preset liquid level threshold and the feeding pressure is within the preset range, then the material conveying mechanism is controlled to start working. During the operation of the material conveying mechanism, the feed concentration, feed flow rate, filtrate water flow rate, and feed time are obtained; based on the feed concentration, feed flow rate, and feed time, the feed quality is determined. If the feed mass is greater than the preset material quantity and the filtrate water flow rate is less than the first preset flow rate threshold, then the material conveying mechanism is controlled to stop working and the filter press is controlled to start working. If the flow rate of the filtrate is less than the second preset flow rate threshold for a number of consecutive preset sampling times starting from the start of the filter press, then the filter press will be controlled to stop pressing and start unloading, and the conveyor will be controlled to start working.

[0012] Optionally, the method further includes: To obtain the quality of the pressed material; An alarm is generated if the difference between the feed quality and the quality of the pressed material is greater than a preset difference.

[0013] Optionally, feed quality can be determined based on feed concentration, feed flow rate, and feed time, including: The feed mass is calculated using the following formula: ; in, For the quality of the feed material; This refers to the feed concentration. This refers to the feed flow rate; This refers to the feeding time.

[0014] Optionally, during the operation of the material conveying mechanism: If the liquid level in the hopper is less than or equal to a preset liquid level threshold and / or the feeding pressure is not within a preset range, the material conveying mechanism will be stopped and an alarm will be generated.

[0015] Optionally, the method further includes: Obtain the actual pressing time of the filter press; By inputting the feeding time, feeding concentration, and filtrate flow rate into the working time prediction model, the theoretical pressing time of the filter press can be obtained. If the difference between the theoretical pressing time and the actual pressing time is greater than a preset fluctuation threshold, an alarm will be generated. The working time prediction model is obtained by training a neural network model using a training dataset, which includes: historical feed time, historical feed concentration, historical filtrate flow rate, and historical pressing time.

[0016] On the other hand, the present invention provides an electronic device including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the above-described automatic control method for the pressing system.

[0017] This technical solution achieves automatic control of the pressing system based on the collected liquid level in the material tank, as well as the feed concentration, feed flow rate, feed pressure, filtrate flow rate, and material quality after pressing. The control method is simple, precise, stable, and efficient, effectively reducing pressing costs.

[0018] Other features and advantages of the embodiments of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0019] The accompanying drawings are provided to further illustrate embodiments of the present invention and form part of the specification. They are used together with the following detailed description to explain the embodiments of the present invention, but do not constitute a limitation thereof. In the drawings: Figure 1This is a schematic diagram of the structure of the first pressing system provided by the present invention; Figure 2 This is a schematic diagram of the structure of the second pressing system provided by the present invention; Figure 3 This is a flowchart of the automatic control method for the pressing system provided by the present invention; Figure 4 This is a structural example diagram of the neural network model provided by the present invention; Figure 5 This is a control block diagram of the pressing system in the embodiments provided by the present invention; Figure 6 This is a flowchart of the intelligent control process for the feeding procedure in the embodiments provided by the present invention; Figure 7 This is a flowchart of the intelligent control process of the pressing process in the embodiments provided by the present invention; Figure 8 This is a flowchart of the intelligent control process for the unloading procedure in the embodiments provided by the present invention.

[0020] Explanation of reference numerals in the attached figures 1-Materials hopper; 2-Filter press; 3-Material conveying mechanism; 4-Conveyor; 5-Data acquisition sensor group; 6-Controller; 7-Industrial control computer; 8-Mobile control terminal; 41-Weighing mechanism; 51-Level gauge; 52-Infeed flow meter; 53-Infeed concentration meter; 54 - Feed pressure gauge; 55 - Filtrate flow meter; 81 - Wireless base station. Detailed Implementation

[0021] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the scope of the present invention.

[0022] In the embodiments of the present invention, unless otherwise stated, directional terms such as "up," "down," "left," and "right" generally refer to the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of the invention is usually placed when in use.

[0023] The terms “first,” “second,” “third,” etc., are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.

[0024] The terms "parallel" and "perpendicular" do not mean that the components must be absolutely parallel or perpendicular, but rather that they can be slightly tilted. For example, "parallel" simply means that its direction is more parallel than "perpendicular," not that the structure must be completely parallel, but that it can be slightly tilted.

[0025] The terms "horizontal," "vertical," and "sag" do not imply that a component must be absolutely horizontal, vertical, or sagging, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," not that the structure must be completely horizontal, but can be slightly tilted.

[0026] Furthermore, terms like "roughly" and "basically" are used to indicate that the content does not require absolute precision, but rather allows for a certain degree of deviation. For example, "roughly equal" does not simply mean absolute equality; in actual production and operation, achieving absolute "equality" is difficult, and a certain degree of deviation is generally present. Therefore, besides absolute equality, "roughly equal to" also includes the aforementioned situation where a certain degree of deviation exists. Using this as an example, in other cases, unless otherwise specified, terms like "roughly" and "basically" have similar meanings.

[0027] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0028] Figure 1 This is a schematic diagram of the structure of the first pressing system provided by the present invention; Figure 2 This is a schematic diagram of the structure of the second pressing system provided by the present invention; Figure 3 This is a flowchart of the automatic control method for the pressing system provided by the present invention; Figure 4 This is a structural example diagram of the neural network model provided by the present invention; Figure 5 This is a control block diagram of the pressing system in the embodiments provided by the present invention; Figure 6 This is a flowchart of the intelligent control process for the feeding procedure in the embodiments provided by the present invention; Figure 7 This is a flowchart of the intelligent control process of the pressing process in the embodiments provided by the present invention; Figure 8 This is a flowchart of the intelligent control process for the unloading procedure in the embodiments provided by the present invention.

[0029] like Figure 1-2 As shown, this embodiment provides a pressing system, the system comprising: Material hopper 1 is used to store the material to be pressed; The filter press 2 has its feed inlet connected to the material barrel 1 via a material conveying mechanism 3. The filter press 2 is used to press the material. Conveyor 4 is located below the discharge port of filter press 2 and is used to transport the pressed material. The conveyor 4 is equipped with a weighing mechanism 41 to obtain the mass of the pressed material. The data acquisition sensor group 5 is used to collect the liquid level in the material tank 1, as well as the feed concentration, feed flow rate, feed pressure and filtrate flow rate of the filter press 2. The controller 6 is connected to the data acquisition sensor group 5, the weighing mechanism 41, the material conveying mechanism 3 and the filter press 2, and is used to control the start and stop of the material conveying mechanism 3, the filter press 2 and the conveyor 4 based on the liquid level in the material tank, the feed concentration, the feed flow rate, the feed pressure, the filtrate water flow rate and the mass of the pressed material.

[0030] Specifically, in this embodiment, the controller 6 can automatically control the start and stop of the material conveying mechanism 3, the filter press 2 and the conveyor 4 based on the collected parameters. The control method is simple, precise, stable and efficient. By replacing manual control of the machine with automatic control, the manpower can be effectively reduced, thereby reducing the pressing cost.

[0031] Furthermore, the material conveying mechanism 3 is a feed pump; The weighing mechanism 41 is a belt scale.

[0032] Specifically, since the material to be pressed is usually a solid-liquid mixture, it is in the form of a slurry. Therefore, by using a feed pump to transport the material, a stable transport of the material can be ensured, and blockages can be effectively avoided.

[0033] The weighing mechanism 41 is set as a belt scale, which has high detection accuracy and is easy to use. It can both transport materials and collect the weight of the materials. Specifically, the material walks on the belt of the belt scale, and the weight of the material acts on the pressure sensor through the metering support frame. The pressure sensor outputs a weight signal. At the same time, a speed sensor measures the speed signal of the belt. By calculating these two signals, the weight of the material is obtained. Then, based on the comparison between the weight of the material and a given quantity, the speed of the motor is adjusted by the frequency converter to control the material speed.

[0034] Furthermore, such as Figure 1-2 As shown, the data acquisition sensor group 5 includes: A level gauge 51 is installed on the material tank 1 to detect the liquid level in the material tank 1; A feed flow meter 52 is installed at the feed inlet of the filter press 2 to detect the feed flow rate of the filter press 2; A feed concentration meter 53 is installed at the feed inlet of the filter press 2 to detect the feed concentration of the filter press 2. A feed pressure gauge 54 is installed at the feed inlet of the filter press 2 to detect the feed pressure of the filter press 2; A filtrate flow meter 55 is installed at the outlet of the filter press 2 to detect the filtrate flow rate of the filter press 2.

[0035] Specifically, in this embodiment, the level gauge 51 is installed inside the material tank 1; the feed inlet of the filter press 2 is connected to the material tank 1 through the material conveying mechanism 3, and the feed inlet of the filter press 2 and the material conveying mechanism 3 can be connected by a pipeline to realize the material conveying, so the feed flow meter 52, the feed concentration meter 53 and the feed pressure meter 54 can be installed on the pipeline; the filtrate water flow meter 55 is installed at an appropriate position in the filtrate water tank of the filter press 2.

[0036] Furthermore, such as Figure 2 As shown, controller 6 is a DCS controller; The system also includes: The industrial computer 7 and the mobile control terminal 8 are respectively connected to the controller 6. The industrial computer 7 and the mobile control terminal 8 are used to generate corresponding control commands based on external input signals and send them to the controller 6. The controller 6 is also used to control the start and stop of the material conveying mechanism 3, the filter press 2 and the conveyor 4 based on the control commands.

[0037] Specifically, in this embodiment, the controller 6 adopts a DCS controller, which has the advantages of high reliability, good openness, high flexibility and stable operation, and can realize automatic control of the material conveying mechanism 3, the filter press 2 and the conveyor 4.

[0038] In addition to automatically controlling the start and stop of the material conveying mechanism 3, filter press 2, and conveyor 4 using controller 6 based on collected data such as tank liquid level, feed concentration, feed flow rate, feed pressure, filtrate flow rate, and pressed material quality, manual control of the material conveying mechanism 3, filter press 2, and conveyor 4 can be achieved by setting up an industrial control computer 7 in the monitoring room or production site. The industrial control computer 7 can be connected to controller 6 via a data cable. Secondly, to increase its practicality, a mobile control terminal 8 is set up to achieve manual control of the start and stop of the material conveying mechanism 3, filter press 2, and conveyor 4. The mobile control terminal 8 can be a mobile phone, tablet, etc. The mobile control terminal 8 connects to controller 6 through a wireless base station 81 deployed in the plant area. At the same time, when controller 6 generates an alarm, it will send an alarm signal to industrial control computer 7 and mobile control terminal 8 to ensure that maintenance personnel can receive the alarm signal in a timely manner, grasp the overall operating status, and carry out maintenance promptly.

[0039] like Figure 3As shown, this embodiment provides an automatic control method for a pressing system, applied to the aforementioned pressing system. The method includes: Obtain the liquid level and feed pressure in the material tank; If the liquid level in the hopper is greater than the preset liquid level threshold and the feeding pressure is within the preset range, then the material conveying mechanism is controlled to start working. During the operation of the material conveying mechanism, the feed concentration, feed flow rate, filtrate water flow rate, and feed time are obtained; The feed quality is determined based on the feed concentration, feed flow rate, and feed time. If the feed mass is greater than the preset material quantity and the filtrate water flow rate is less than the first preset flow rate threshold, then the material conveying mechanism is controlled to stop working and the filter press is controlled to start working. If the flow rate of the filtrate is less than the second preset flow rate threshold for a number of consecutive preset sampling times starting from the start of the filter press, then the filter press will be controlled to stop pressing and start unloading, and the conveyor will be controlled to start working.

[0040] Specifically, in this embodiment, the above-described scheme is used to achieve automatic control of the start and stop of the material conveying mechanism 3, the filter press 2, and the conveyor 4. Multiple process parameters, such as feed concentration, feed flow rate, filtrate water flow rate, and feed time, are employed to ensure the stability and accuracy of control, effectively avoid miscontrol, and improve operational safety. The number of continuous sampling moments can be set to 5 seconds, which can be adjusted according to actual needs.

[0041] Furthermore, the method also includes: To obtain the quality of the pressed material; An alarm is generated if the difference between the feed quality and the quality of the pressed material is greater than a preset difference.

[0042] Specifically, in this embodiment, after the material is pressed by the filter press, the filter press discharges the material to the conveyor 4. However, during the pressing process, the material may stick to the filter cloth of the filter press. Therefore, the quality of the pressed material discharged does not match the feed quality estimated by the parameters. Therefore, if the difference between the feed quality and the quality of the pressed material is greater than the preset difference, an alarm is generated to notify the maintenance personnel to carry out maintenance in order to avoid reducing the subsequent pressing efficiency and control errors, as well as causing damage to the equipment.

[0043] Furthermore, based on the feed concentration, feed flow rate, and feed time, the feed quality is determined, including: The feed mass is calculated using the following formula: ; in, For the quality of the feed material; This refers to the feed concentration. This refers to the feed flow rate; This refers to the feeding time.

[0044] Specifically, in this embodiment, the 0- is calculated based on the feed concentration, feed flow rate, and feed time using the above calculation formula. T The quality of the feed material within a given time period ensures the accuracy of the calculation results.

[0045] Furthermore, during the operation of the material conveying mechanism: If the liquid level in the hopper is less than or equal to a preset liquid level threshold and / or the feeding pressure is not within a preset range, the material conveying mechanism will be stopped and an alarm will be generated.

[0046] Specifically, in this embodiment, as the pressing proceeds, the amount of material in the barrel will gradually decrease. When the liquid level in the barrel is less than or equal to the preset liquid level threshold and / or the feed pressure is not within the preset range, it indicates that the amount of material in the barrel is too small, resulting in a low feed pressure on the press, making it impossible to provide stable material supply. Alternatively, the feed inlet of the filter press may be blocked, causing the feed pressure to be too high and not within the preset range. In this case, the material conveying mechanism will be controlled to stop working and an alarm will be generated to remind the staff to carry out maintenance and avoid damage to the equipment.

[0047] Furthermore, the method also includes: Obtain the actual pressing time of the filter press; By inputting the feeding time, feeding concentration, and filtrate flow rate into the working time prediction model, the theoretical pressing time of the filter press can be obtained. If the difference between the theoretical pressing time and the actual pressing time is greater than a preset fluctuation threshold, an alarm will be generated. The working time prediction model is obtained by training a neural network model using a training dataset, which includes: historical feed time, historical feed concentration, historical filtrate flow rate, and historical pressing time.

[0048] Specifically, in this embodiment, in order to fully understand the operating status of the filter press, the feeding time, feeding concentration, and filtrate flow rate are used as inputs to the working time prediction model. This allows the theoretical pressing time of the filter press to be obtained. Furthermore, the predicted theoretical pressing time is compared with the actual pressing time of the filter press. If the difference between the theoretical and actual pressing times is less than or equal to a preset fluctuation threshold, it indicates that the two times are relatively close, proving that the filter press is operating stably and meets expectations. If the difference between the theoretical and actual pressing times is greater than or equal to the preset fluctuation threshold, it indicates that the two times differ significantly, proving that the filter press is operating unstable and may have certain operational abnormalities. Therefore, an alarm is generated to remind the staff to carry out maintenance and avoid damage to the equipment.

[0049] More specifically, if no abnormal operation of the equipment is found after maintenance by the staff, it indicates that the prediction results of the working time prediction model are inaccurate. The working time prediction model should be corrected by using the actual pressing time, the corresponding feeding time, the feeding concentration, and the filtrate flow rate to improve the accuracy of the model.

[0050] More specifically, the training dataset includes: historical feed time, historical feed concentration, historical filtrate flow rate, and historical pressing time; the historical feed time, historical feed concentration, and historical feed filtrate flow rate are used as inputs to the neural network model, and the historical pressing time is used as the output of the neural network model to train the neural network model and obtain the working time prediction model.

[0051] like Figure 4 As shown, the process of building and training the working time prediction model is as follows: The neural network model consists of an input layer, an output layer, and two intermediate layers. Each layer's output generates a set of activation functions that process the results. The final result of these activation functions is then used as the output of the output layer.

[0052] The input layer has three neurons, a1, a2, and a3, and the first intermediate layer has two neurons, b1 and b2. Therefore, the activation function of the first layer is: b1 = a1*m1,1 + a2*m2,1 + a3*m3,1; b2 = a2*m1,2 + a2*m2,2 + a3*m3,2; Where m1,1,m1,2,m2,1 and m2,2 are the weights of the activation function.

[0053] The first intermediate layer has two neurons, c1 and c2. Therefore, the activation function for the second layer is: c1 = b1 * n1,1 + b2 * n2,1; c2 = b1*n1,2 + b2*n2,2; Where n1,1,n1,2,n2,1 and n2,2 are the weights of the activation function.

[0054] The output layer has only one neuron, z1; Therefore, the activation function for the third layer is: z1 = c1 * g1 + c2 * g2; Where g1 and g2 are the weights of the activation function.

[0055] The final functions of input layer neurons a1, a2, and a3 and output layer neuron z1 are: z1=[(a1*m1,1+a2*m2,1+a3*m3,1)*n1,1+(a2*m1,2+a2*m2,2+a3*m3,2)*n2,1]*g 1+[a1*m1,1+a2*m2,1+a3*m3,1)*n1,2+(a2*m1,2+a2*m2,2+a3*m3,2)*n2,2]*g2; The DCS uses the historical data of each pressing, including feed time, feed concentration, and feed filtrate flow rate, as input layer neurons a1, a2, and a3 of the neural network model. The final pressing time of that pressing is used as the output layer result z1 to train the neural network model.

[0056] This embodiment also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the above-described automatic control method for the pressing system.

[0057] Example: In this embodiment, as Figure 5 As shown, the controller uses a DCS system for automatic control, which integrates intelligent control algorithms S1 for the feeding process, S2 for the pressing process, and S3 for the unloading process, thereby achieving intelligent automatic control of the feeding, pressing, and unloading processes. like Figure 6 As shown, the intelligent control S1 of the feeding process includes: start feeding control S101, process feeding control S102 and stop feeding control S103.

[0058] The implementation scheme for the start-up feed control S101 is as follows: In process a1, the DCS obtains the feed pipeline pressure through the feed pressure gauge 54. When the feed pressure meets the upper and lower limits of the feed (within the preset range), it determines that the feed start-up condition 1 is met. The upper and lower limits of the feed pressure are determined based on the filter press parameters and the on-site process parameters, and are not used as process control indicators.

[0059] In process a2, the DCS obtains the liquid level of the feed tank 1 through the level gauge 51. When the current liquid level of the feed tank 1 meets the feeding limit (greater than the preset liquid level threshold), it is determined that the feeding start condition 2 is met. The feeding tank liquid level limit is determined based on the filter press parameters and the on-site process parameters, and is not used as an indicator of process control.

[0060] In process a3, after the DCS simultaneously meets feeding condition 1 and feeding condition 2, it starts the feeding pump and begins feeding.

[0061] The implementation scheme for process feed control S102 is as follows: In process a4, if the liquid level in tank 1 suddenly drops to the pump stop level limit during the feeding process, the feed pump will be stopped. The pump stop level limit is determined based on the filter press parameters and on-site process parameters and is not used as a process control indicator.

[0062] In process a5, after the feed pump stops in process a4, if the liquid level in tank 1 is sufficient to complete the feeding, the feed pump is restarted. The conditions sufficient to complete the feeding can be determined by level gauge 51 and are not used as process control indicators.

[0063] In process a6, the feed pressure gauge 54 is monitored. When the pressure exceeds the upper limit, an alarm message is sent to the industrial control computer 7 and the mobile control terminal 8. Operators of the industrial control computer 7 and the mobile control terminal 8 can manually or automatically start or stop the feed pump using the DCS. The upper limit pressure value is set by process parameters and is not used as a process control indicator.

[0064] The implementation scheme for the stop-feed control S103 is as follows: In process a7, the DCS obtains the feed concentration C and feed flow rate Q1 through the feed flow meter 52 and feed concentration meter 53, and calculates the feed mass M. When the feed mass M reaches the filter press's processing capacity Mset, and M ≥ Mset, process a8 is executed.

[0065] In process a8, the DCS obtains the filtrate flow rate Q2 during the feeding process through the filtrate flow meter 55. When Q2 is 0, the feed pump is stopped, and process a9 is executed.

[0066] In process a9, the feed pump is stopped. The intelligent control algorithm S1 for the feed process ends, and the intelligent control algorithm S2 for the pressing process is executed.

[0067] like Figure 7 As shown, the implementation scheme of the intelligent control algorithm S2 for the pressing process is as follows: In process S201, the DCS performs mathematical modeling based on historically stored feed concentration, feed filtrate flow rate, and actual pressing time. It then automatically sets the pressing time t1 according to the current feed concentration C and feed filtrate flow rate Q1. Process S202 is then executed.

[0068] In process S202, the DCS acquires the filtrate water flow rate Q3 in the filtrate water tank during the pressing process. If the filtrate water flow rate Q3 in the filtrate water tank is continuously less than the flow rate limit (second preset flow rate threshold), the pressing is determined to be complete, and process S203 is executed. The flow rate limit mentioned above is determined by the filter press parameters and is not used as a process control indicator.

[0069] In process S203, the DCS performs mathematical modeling based on historically stored feed concentration, feed filtrate flow rate, and actual pressing time. It automatically sets the pressing time t1 based on the current feed concentration C and feed filtrate flow rate Q1. The DCS acquires the flow rate Q3 of the filtrate tank during pressing and determines that pressing is complete when Q3 is less than the set minimum pressing flow rate. The DCS memorizes the feed concentration C, the feed filtrate flow rate Q1, and the actual pressing time t2, and corrects the mathematical model for setting the pressing time. The minimum pressing flow rate is determined based on the filter press parameters and is not used as a process control indicator.

[0070] like Figure 8 As shown, the intelligent control S1 of the feeding process includes start unloading control S301, process unloading control S302 and stop unloading control S303.

[0071] The implementation plan for starting unloading control S301 is as follows: In process c1, the DCS controls the filter press 2 to perform a loosening operation, and then process c2 is executed.

[0072] In process c2, the DCS controls the downstream conveyor 4 of filter press 2 to start, thus executing process c3.

[0073] In process c3, after the DCS receives the operation feedback signal from the downstream conveyor 4, it starts the unloading process and executes the plate picking and pulling operations. The unloading start control S301 ends, and the unloading process control S302 begins.

[0074] The implementation plan for process unloading control S202 is as follows: In process c4, the DCS determines the required mass M1 of each plate based on the feed mass M and the process parameters of the filter press, and obtains the material mass M2 of each plate unloading from the filter press through a belt scale, and then executes process c5.

[0075] In process c5, the DCS calculates the difference between M1 and M2. If M1 - M2 ≥ n (n = 0.01t), it is determined that the material is adhering to the filter cloth. The DCS pushes an alarm message to the industrial control computer 7 and the mobile control terminal 8. The operators of the industrial control computer 7 and the mobile control terminal 8 can control the DCS to start and stop the filter press 2. The value of n can be adjusted based on the on-site process parameters and is not used as an indicator of process control. If M1 - M2 < n (n = 0.01t), the stop unloading control S303 is executed.

[0076] In process c6, the DCS remembers the number of times the plates are picked up and pulled. When the number of times remembered is the same as the number of plates in the filter press, process c7 is executed.

[0077] In process c7, the DCS stops conveyor 4, terminates unloading, ends the unloading process, and begins the feeding process.

[0078] The optional embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the embodiments of the present invention are not limited to the specific details in the above embodiments. Within the scope of the technical concept of the embodiments of the present invention, various simple modifications can be made to the technical solutions of the embodiments of the present invention, and these simple modifications all fall within the protection scope of the embodiments of the present invention.

[0079] Those skilled in the art will understand that all or part of the steps in the methods of the above embodiments can be implemented by a program instructing related hardware. This program is stored in a storage medium and includes several instructions to cause a microcontroller, chip, or processor to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as a USB flash drive, a portable hard drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0080] The optional embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the embodiments of the present invention are not limited to the specific details described above. Within the scope of the technical concept of the embodiments of the present invention, various simple modifications can be made to the technical solutions of the embodiments of the present invention, and these simple modifications all fall within the protection scope of the embodiments of the present invention. It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the embodiments of the present invention will not describe the various possible combinations separately. Furthermore, various different implementations of the present invention can be combined arbitrarily, as long as they do not violate the spirit of the present invention, they should also be regarded as the content disclosed in the present invention.

Claims

1. An automatic control method for a pressing system, characterized in that, The system includes: Material hopper (1), used to store materials to be pressed; A filter press (2) is provided, the feed inlet of which is connected to the material barrel (1) via a material conveying mechanism (3). The filter press (2) is used to press the material. A conveyor (4) is set below the outlet of the filter press (2) for conveying the pressed material. A weighing mechanism (41) is set on the conveyor (4) for obtaining the mass of the pressed material. The data acquisition sensor group (5) is used to collect the liquid level of the material tank (1), as well as the feed concentration, feed flow rate, feed pressure and filtrate flow rate of the filter press (2); The controller (6) is connected to the data acquisition sensor group (5), the weighing mechanism (41), the material conveying mechanism (3) and the filter press (2), and is used to control the start and stop of the material conveying mechanism (3), the filter press (2) and the conveyor (4) based on the liquid level in the material tank, the feed concentration, the feed flow rate, the feed pressure, the filtrate water flow rate and the mass of the material after pressing; The method includes: Obtain the liquid level and feed pressure in the material tank; If the liquid level in the hopper is greater than the preset liquid level threshold and the feeding pressure is within the preset range, then the material conveying mechanism is controlled to start working. During the operation of the material conveying mechanism, the feed concentration, feed flow rate, filtrate water flow rate, and feed time are obtained; based on the feed concentration, feed flow rate, and feed time, the feed quality is determined. If the feed mass is greater than the preset material quantity and the filtrate water flow rate is less than the first preset flow rate threshold, then the material conveying mechanism is controlled to stop working and the filter press is controlled to start working. If the flow rate of the filtrate is less than the second preset flow rate threshold for a number of consecutive preset sampling times starting from the start of the filter press, then the filter press will be controlled to stop pressing and start unloading, and the conveyor will be controlled to start working. The method further includes: To obtain the quality of the pressed material; An alarm is generated if the difference between the feed quality and the quality of the pressed material is greater than a preset difference.

2. The automatic control method for the pressing system according to claim 1, characterized in that, The material conveying mechanism (3) is a feed pump; The weighing mechanism (41) is a belt scale.

3. The automatic control method for the pressing system according to claim 1, characterized in that, The data acquisition sensor group (5) includes: A level gauge (51) is installed on the material tank (1) to detect the liquid level in the material tank (1); A feed flow meter (52) is installed at the feed inlet of the filter press (2) to detect the feed flow rate of the filter press (2); A feed concentration meter (53) is installed at the feed inlet of the filter press (2) to detect the feed concentration of the filter press (2); A feed pressure gauge (54) is installed at the feed inlet of the filter press (2) to detect the feed pressure of the filter press (2); A filtrate flow meter (55) is installed at the outlet of the filter press (2) to detect the filtrate flow rate of the filter press (2).

4. The automatic control method for the pressing system according to claim 1, characterized in that, The controller (6) is a DCS controller; The system also includes: The industrial computer (7) and the mobile control terminal (8) are respectively connected to the controller (6) for communication. The industrial computer (7) and the mobile control terminal (8) are used to generate corresponding control commands based on external input signals and send them to the controller (6). The controller (6) is also used to control the start and stop of the material conveying mechanism (3), the filter press (2) and the conveyor (4) based on control commands.

5. The automatic control method for the pressing system according to claim 1, characterized in that, The feed quality is determined based on feed concentration, feed flow rate, and feed time, including: The feed mass is calculated using the following formula: ； in, For the quality of the feed material; This refers to the feed concentration. This refers to the feed flow rate; This refers to the feeding time.

6. The automatic control method for the pressing system according to claim 1, characterized in that, During the operation of the material conveying mechanism: If the liquid level in the hopper is less than or equal to a preset liquid level threshold and / or the feeding pressure is not within a preset range, the material conveying mechanism will be stopped and an alarm will be generated.

7. The automatic control method for the pressing system according to claim 1, characterized in that, The method further includes: Obtain the actual pressing time of the filter press; By inputting the feeding time, feeding concentration, and filtrate flow rate into the working time prediction model, the theoretical pressing time of the filter press can be obtained. If the difference between the theoretical pressing time and the actual pressing time is greater than a preset fluctuation threshold, an alarm will be generated. The working time prediction model is obtained by training a neural network model using a training dataset, which includes: historical feed time, historical feed concentration, historical filtrate flow rate, and historical pressing time.

8. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the automatic control method of the pressing system according to any one of claims 1-7.

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