A mica slurry online concentration control system and method

Abstract

The present invention belongs to the technical field of slurry concentration detection in papermaking production, and specifically provides a mica slurry online concentration control system and method, including a mica slurry pool, which is provided with a slurry feed port and a slurry discharge port, and also includes a concentration detection module, a concentration adjustment module and a central controller. The concentration detection module takes out part of the sample from the mica slurry pool for weighing detection to obtain the slurry concentration; the central controller sends a feedback signal to the concentration adjustment module in real time according to the slurry concentration; the concentration adjustment module injects clean water into the mica slurry pool according to the feedback signal to adjust the slurry concentration. The system is simple and easy to operate, with low equipment loss and low cost. After using this system solution, the concentration control effect is stable and reliable; the equipment can maintain normal operation for a long time; and the quality of mica paper products is greatly improved.

Description

Technical Field

[0001] The invention belongs to the technical field of slurry concentration detection in papermaking production, and in particular relates to an online concentration control system and method for mica slurry. Background Art

[0002] Pulp is a fibrous material made from plant fiber through different processing methods. It can be divided into mechanical pulp, chemical pulp and chemical mechanical pulp according to the processing method; it can also be divided into wood pulp, straw pulp, hemp pulp, reed pulp, sugarcane pulp, bamboo pulp, rag pulp, etc. according to the fiber raw materials used. It can also be divided into refined pulp, bleached pulp, unbleached pulp, high-yield pulp, semi-chemical pulp, etc. according to different purities. It is generally used to make paper and cardboard. Pulp concentration is one of the important standards for verifying paper quality. Pulp concentration is affected by water flow, raw material flow or manual operation, resulting in unstable pulp concentration, which in turn affects the quality of the product. The existing pulp concentration detection accuracy is low, and it is impossible to make further improvement measures on the pulp concentration, resulting in varying degrees of impact on the quality of the finished paper.

[0003] The current detection technology is to add optical or other principle probes to the pipeline to detect the concentration of the solution in real time. It can reflect the actual situation when the suspended particles are regular and uniform. However, the suspended matter in the mica slurry is ore scales, which have a poor refraction effect on light and cannot meet the requirements of stable concentration measurement; secondly, the scales will cause damage to the detection probe when they are washed, and the damage rate of the equipment placed in it is very high. Based on the above situation, the online closed-loop control of mica slurry concentration in the mica industry mostly does not meet the requirements of industrial applications. Summary of the invention

[0004] The purpose of the present invention is to overcome the problems of low efficiency and high cost in the prior art for detecting the concentration of mica slurry.

[0005] To this end, the present invention provides a mica slurry online concentration control system, including a mica slurry pool, the mica slurry pool is provided with a slurry feed port and a slurry discharge port, and also includes a concentration detection module, a concentration adjustment module and a central controller;

[0006] The concentration detection module includes a weighing mechanism for sampling and weighing, the weighing mechanism is connected to the mica slurry pool through a sampling pipeline, and the weighing mechanism is electrically connected to the central controller;

[0007] The concentration adjustment module is used to adjust the slurry concentration of the mica slurry pool;

[0008] The central controller is used to receive the concentration detection signal of the weighing mechanism and feedback control the concentration adjustment module.

[0009] Preferably, a sampling valve is provided on the sampling pipeline, the weighing mechanism comprises a sample outlet, a sample outlet is provided on the sample outlet, and the sampling valve and the sample outlet are both electrically connected to the central controller.

[0010] Preferably, the inlet end of the sampling pipeline is connected to the mica slurry pool, and the outlet end is connected to the weighing mechanism, and the height of the inlet end is higher than the height of the outlet end.

[0011] Preferably, the sampling pipeline includes a first sampling pipeline, a second sampling pipeline and a sampling collection pipeline, and the height of the inlet end of the first sampling pipeline is higher than the height of the inlet end of the second sampling pipeline.

[0012] Preferably, the diameter of the sampling collection pipeline is larger than the sum of the diameters of the first sampling pipeline and the second sampling pipeline.

[0013] Preferably, the concentration detection module includes a concentration regulating water inlet, one end of which is connected to external clean water, and the other end is connected to the search mica slurry pool. A concentration regulating valve is provided on the concentration regulating water inlet, and the concentration regulating valve is electrically connected to the central controller.

[0014] Preferably, a stirrer for rotating the slurry needle is provided in the mica slurry pool, and the inlet of the sampling pipeline is located in the rotating slurry.

[0015] The present invention also provides a mica slurry online concentration control method, comprising:

[0016] The concentration detection module takes out some samples from the mica slurry pool for weighing and detection to obtain the slurry concentration;

[0017] The central controller sends a feedback signal to the concentration adjustment module in real time according to the slurry concentration;

[0018] The concentration regulating module injects clean water into the mica slurry pool according to the feedback signal to adjust the slurry concentration.

[0019] Preferably, the concentration regulating module comprises a concentration regulating valve, and the concentration regulating valve controls the valve opening in real time through a PID control algorithm.

[0020] Preferably, the concentration detection module comprises a weighing mechanism, the mass of the weighing mechanism filled with pure water is m1, the mass of the weighing mechanism filled with sample slurry is m2, and the slurry concentration is λ1=(m2-m1)*100% / m2.

[0021] Beneficial effects of the present invention: The mica slurry online concentration control system and method provided by the present invention comprises a mica slurry pool, which is provided with a slurry feed port and a slurry discharge port, and also comprises a concentration detection module, a concentration adjustment module and a central controller. The concentration detection module takes out part of the sample from the mica slurry pool for weighing detection to obtain the slurry concentration; the central controller sends a feedback signal to the concentration adjustment module in real time according to the slurry concentration; the concentration adjustment module injects clean water into the mica slurry pool according to the feedback signal to adjust the slurry concentration. The system is simple and easy to operate, with low equipment loss and low cost. After using this system solution, the concentration control effect is stable and reliable; the equipment can maintain normal operation for a long time; and the quality of mica paper products is greatly improved.

[0022] The present invention will be further described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a functional module schematic diagram of the mica slurry online concentration control system and method of the present invention;

[0024] Figure 2 It is a structural block diagram of the mica slurry online concentration control system and method of the present invention;

[0025] Figure 3 It is a physical diagram of the mica slurry online concentration control system and method of the present invention;

[0026] Figure 4 It is a schematic diagram of the pipeline structure of the concentration detection module of the mica slurry online concentration control system and method of the present invention.

[0027] Description of reference numerals: feed valve 1, discharge valve 2, concentration regulating valve 3, first sampling valve 4, second sampling valve 5, sampling summary valve 6, mica slurry pool 7, weighing mechanism 8, sample discharge valve 9;

[0028] Slurry feed port A, concentration adjustment water inlet B, slurry discharge port C, first sampling pipeline E, second sampling pipeline F, sampling summary pipeline G, sample discharge port J. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] In the description of the present invention, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention 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 understood as a limitation on the present invention.

[0031] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features; in the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0032] The embodiment of the present invention provides a mica slurry online concentration control system, such as Figure 1 As shown, it includes a mica slurry pool 7, which is provided with a slurry feed port A and a slurry discharge port C, and also includes a concentration detection module, a concentration adjustment module and a central controller; the concentration detection module includes a weighing mechanism 8 for sampling and weighing, the weighing mechanism 8 is connected to the mica slurry pool 7 through a sampling pipeline, and the weighing mechanism 8 is electrically connected to the central controller; the concentration adjustment module is used to adjust the slurry concentration of the mica slurry pool 7; the central controller is used to receive the concentration detection signal of the weighing mechanism 8 and feedback control the concentration adjustment module.

[0033] First, the slurry is input into the mica slurry pool 7 through the slurry feed port A. Specifically, the opening can be controlled by the feed valve 1 on the slurry feed port A. When the slurry volume reaches a certain level, the feed valve 1 is closed or the opening of the feed valve 1 is reduced, and then the concentration detection module is turned on. First, the ideal value of the slurry concentration in the mica slurry pool 7 is set to λ, and the allowable floating value deviation D is set. The slurry concentration in the mica slurry pool 7 is detected by the concentration detection module, and the current concentration value λ0 is obtained by the sampling weighing comparison method. The specific weighing method will be further described in detail later. Then the central controller calculates the concentration adjustment value through the PID algorithm, that is, the proportion, differential and integral. The concentration adjustment value is transmitted to the concentration adjustment module as a feedback signal, and the concentration adjustment module then adjusts the slurry concentration in the mica slurry pool 7 in real time. After the adjustment is completed, the ideal slurry is discharged through the slurry outlet. Among them, a discharge valve 2 is provided on the slurry outlet, and the discharge and detection of the slurry are coordinated by opening and closing the discharge valve 2.

[0034] In a preferred solution, a sampling valve is provided on the sampling pipeline, the weighing mechanism 8 includes a sample outlet J, a sample outlet valve 9 is provided on the sample outlet J, and the sampling valve and the sample outlet valve 9 are both electrically connected to the central controller. Figure 2 As shown, the sampling valve is opened, and the slurry sample enters the weighing mechanism 8 from the sampling pipe for weighing. Assuming that the internal volume of the weighing mechanism 8 is V, the mass of the volume V filled with pure water is m1, and the mass obtained after the actual sampling and filling with slurry is m2, then the current slurry concentration λ0 is approximately:

[0035] λ0=(m2-m1)*100% / m2

[0036] To ensure the representativeness of the effect, multiple concentration detection modules can be arranged on the mica slurry pool 7, and the weighing mechanism 8 in each concentration detection module is used to perform weighing detection sampling, and the average value is taken after the sample is collected and tested. Assuming there are n concentration detection modules, the current slurry concentration finally obtained is:

[0037] λ0=(λ1+λ2……+λ n ) / n

[0038] In a preferred solution, the inlet end of the sampling pipeline is connected to the mica slurry pool 7, and the outlet end is connected to the weighing mechanism 8, and the height of the inlet end is higher than the height of the outlet end. The height difference facilitates the slurry to automatically flow into the weighing mechanism 8, which can save unnecessary extraction pumps and save costs.

[0039] In a preferred embodiment, the sampling pipeline includes a first sampling pipeline E, a second sampling pipeline F and a sampling collection pipeline G, and the height of the inlet end of the first sampling pipeline E is higher than the height of the inlet end of the second sampling pipeline F. Figures 2 to 4 As shown, the first sampling pipeline E and the second sampling pipeline F are both connected to the mica slurry pool 7, on which the first sampling valve 4 and the second sampling valve 5 are respectively provided, and all valves are controlled by a central controller. The two sampling valves are connected to the sampling summary pipeline G after being combined, and a sampling summary valve 6 is provided at the connection. During sampling, the sampling summary valve 6 is closed, and the first sampling valve 4 and the second sampling valve 5 are opened first, and the first sampling valve 4 and the second sampling valve 5 are closed after a certain period of time. At this time, the volume of slurry in the pipeline is constant. By designing the size and length of the pipeline, the volume of slurry in the pipeline can be made just equal to the volume V of the weighing mechanism 8. Then open the sampling main valve to allow all the sampled slurry in the pipeline to flow into the weighing mechanism 8 for weighing.

[0040] Among them, the height of the first sampling pipe E is higher than the height of the second sampling pipe F. The pressure difference between the two places is used to ensure that the pipe is filled with liquid during the opening process, that is, the sampling volume can be guaranteed to be stable and consistent. In addition, all pipes in each concentration detection module have a certain slope to ensure that the slurry discharged from the sample can be smoothly discharged into the weighing mechanism 8 for weighing, thereby reducing the deviation caused by the residue in the pipe and improving the concentration detection accuracy.

[0041] In a preferred solution, the diameter of the sampling collection pipe G is larger than the sum of the diameters of the first sampling pipe E and the second sampling pipe F. This is beneficial for rapid discharge of slurry and prevents blockage.

[0042] In a preferred solution, the concentration detection module includes a concentration regulating water inlet B, one end of which is connected to the external clean water, and the other end is connected to the search mica slurry pool 7. The concentration regulating water inlet B is provided with a concentration regulating valve 3, and the concentration regulating valve 3 is electrically connected to the central controller. Figure 1 As shown, when a change in the current slurry concentration is detected, the opening of the concentration regulating valve 3 is adjusted in real time according to the sampled concentration value, and the concentration of the slurry can be adjusted by injecting clean water.

[0043] In a preferred solution, a stirrer for rotating the slurry needle is provided in the mica slurry pool 7, and the inlet of the sampling pipeline is located in the rotating slurry. The solution inside the mica slurry pool 7 swirls in a counterclockwise direction. When the first sampling valve 4 and the second sampling valve 5 are opened, the slurry in the mica slurry pool 7 will flush them, which can prevent valve blockage on the one hand, and ensure that no cavity will appear during the closing process of the sampling valve, thereby improving the final detection accuracy.

[0044] An embodiment of the present invention also provides an online concentration control method for mica slurry, comprising: a concentration detection module takes out part of the sample from the mica slurry pool 7 for weighing detection to obtain the slurry concentration; a central controller sends a feedback signal to the concentration adjustment module in real time according to the slurry concentration; the concentration adjustment module injects clean water into the mica slurry pool 7 according to the feedback signal to adjust the slurry concentration.

[0045] The specific sampling process is as follows: first open the sample discharge port J to drain the sample in the weighing mechanism 8, and then close it after draining. Close the sampling summary valve 6 on the sampling summary pipe G, and then open the first sampling valve 4. After a period of time, open the second sampling valve 5. After a certain period of time, first close the first sampling valve 4, and then close the second sampling valve 5. After both sampling valves are closed, it means that the sampling pipeline has been filled with sample slurry. At this time, open the sampling summary valve 6, and the sample slurry automatically flows into the weighing mechanism 8 for weighing to obtain the sampling weight. After calculation by the central controller, the PID algorithm is used to adjust the opening of the concentration regulating valve 3 to adjust the slurry concentration in the mica slurry pool 7. Repeat this process.

[0046] The concentration detection module uses three electric valves to control a pure pipe system, whose internal volume is V, the mass of pure water in this volume is m1, and the mass obtained by actual sampling is m2. The concentration λ0 of the solution is approximately:

[0047] λ0=(m2-m1)*100% / m2

[0048] In order to ensure the representativeness of the effect, n concentration detection modules can be evenly distributed outside the mica slurry pool 7, and the data can be collected at the same time to take the average value:

[0049] λ0=(λ1+λ2……+λ n ) / n

[0050] Sampling this value will be able to filter out individual deviations in the system and greatly improve the control stability of the system.

[0051] Beneficial effects of the present invention: The mica slurry online concentration control system and method provided by the present invention comprises a mica slurry pool, which is provided with a slurry feed port and a slurry discharge port, and also comprises a concentration detection module, a concentration adjustment module and a central controller. The concentration detection module takes out part of the sample from the mica slurry pool for weighing detection to obtain the slurry concentration; the central controller sends a feedback signal to the concentration adjustment module in real time according to the slurry concentration; the concentration adjustment module injects clean water into the mica slurry pool according to the feedback signal to adjust the slurry concentration. The system is simple and easy to operate, with low equipment loss and low cost. After using this system solution, the concentration control effect is stable and reliable; the equipment can maintain normal operation for a long time; and the quality of mica paper products is greatly improved.

[0052] The above examples are merely illustrative of the present invention and do not constitute a limitation on the protection scope of the present invention. All designs that are the same or similar to the present invention fall within the protection scope of the present invention.

Claims

1. A mica slurry online concentration control system, comprising a mica slurry pool, wherein the mica slurry pool is provided with a slurry feed port and a slurry discharge port, characterized in that: It also includes a concentration detection module, a concentration adjustment module and a central controller; The concentration detection module includes a weighing mechanism for sampling and weighing, the weighing mechanism is connected to the mica slurry pool through a sampling pipeline, and the weighing mechanism is electrically connected to the central controller; The concentration adjustment module is used to adjust the slurry concentration of the mica slurry pool; The central controller is used to receive the concentration detection signal of the weighing mechanism and feedback control the concentration adjustment module; The inlet end of the sampling pipeline is connected to the mica slurry pool, and the outlet end is connected to the weighing mechanism. The height of the inlet end is higher than the height of the outlet end. The sampling pipeline includes a first sampling pipeline, a second sampling pipeline and a sampling summary pipeline. The inlet ends of the first sampling pipeline and the second sampling pipeline are respectively connected to the mica slurry pool, and the outlet ends of the first sampling pipeline and the second sampling pipeline are both connected to the inlet end of the sampling summary pipeline. The outlet end of the sampling summary pipeline is connected to the weighing mechanism. The height of the inlet end of the first sampling pipeline is higher than the height of the inlet end of the second sampling pipeline. The first sampling pipeline is provided with a first sampling valve. The second sampling pipeline is provided with a second sampling valve, and the first sampling valve and the second sampling valve are connected to the sampling summary pipeline after being combined, and a sampling summary valve is provided at the connection; when sampling, the sampling summary valve is closed, and the first sampling valve and the second sampling valve are opened first, and the first sampling valve and the second sampling valve are closed after a certain period of time. At this time, the volume of slurry in the pipeline is constant. By designing the size and length of the pipeline, the volume of slurry in the pipeline is equal to the volume of the weighing mechanism, and then the sampling summary valve is opened to allow all the sampled slurry in the pipeline to flow into the weighing mechanism for weighing; the mass of the weighing mechanism after being filled with pure water is m1, and the mass of the weighing mechanism after being filled with sample slurry is m2, then the slurry concentration is .

2. The mica slurry online concentration control system according to claim 1, characterized in that: The weighing mechanism comprises a sample outlet, and a sample outlet valve is arranged on the sample outlet. The sampling valve and the sample outlet valve are both electrically connected to the central controller.

3. The mica slurry online concentration control system according to claim 1, characterized in that: The diameter of the sampling summary pipeline is greater than the sum of the diameters of the first sampling pipeline and the second sampling pipeline.

4. The mica slurry online concentration control system according to claim 1, characterized in that: The concentration detection module includes a concentration regulating water inlet, one end of which is connected to external clean water, and the other end is connected to the mica slurry pool. A concentration regulating valve is provided on the concentration regulating water inlet, and the concentration regulating valve is electrically connected to the central controller.

5. The mica slurry online concentration control system according to claim 2, characterized in that: The mica slurry pool is provided with a stirrer for rotating the slurry needle, and the inlet of the sampling pipeline is located in the rotating slurry.

6. A mica slurry online concentration control method, characterized in that: include: The concentration detection module takes out some samples from the mica slurry pool for weighing and detection to obtain the slurry concentration; The central controller sends a feedback signal to the concentration adjustment module in real time according to the slurry concentration; The concentration regulating module injects clean water into the mica slurry pool according to the feedback signal to adjust the slurry concentration; The concentration detection module includes a weighing mechanism for sampling and weighing, the weighing mechanism is connected to the mica slurry pool through a sampling pipeline, and the weighing mechanism is electrically connected to the central controller; the inlet end of the sampling pipeline is connected to the mica slurry pool, and the outlet end is connected to the weighing mechanism, and the height of the inlet end is higher than the height of the outlet end; the sampling pipeline includes a first sampling pipeline, a second sampling pipeline and a sampling summary pipeline, the inlet ends of the first sampling pipeline and the second sampling pipeline are respectively connected to the mica slurry pool, the outlet ends of the first sampling pipeline and the second sampling pipeline are both connected to the inlet end of the sampling summary pipeline, the outlet end of the sampling summary pipe is connected to the weighing mechanism, and the height of the inlet end of the first sampling pipeline is higher than the height of the outlet end. The height of the inlet end of the two sampling pipelines; the first sampling pipeline is provided with a first sampling valve, the second sampling pipeline is provided with a second sampling valve, the first sampling valve and the second sampling valve are connected to the sampling summary pipeline after being combined, and a sampling summary valve is provided at the connection; when sampling, the sampling summary valve is closed, the first sampling valve and the second sampling valve are opened first, and the first sampling valve and the second sampling valve are closed after a certain period of time. At this time, the volume of slurry in the pipeline is constant. By designing the size and length of the pipeline, the volume of slurry in the pipeline is equal to the volume of the weighing mechanism, and then the sampling summary valve is opened to allow all the sampled slurry in the pipeline to flow into the weighing mechanism for weighing; the mass of the weighing mechanism after being filled with pure water is m1, and the mass of the weighing mechanism after being filled with sample slurry is m2, then the slurry concentration is .

7. The method for controlling the concentration of mica slurry online according to claim 6, characterized in that: The concentration regulating module comprises a concentration regulating valve, and the concentration regulating valve controls the valve opening in real time through a PID control algorithm.

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