Online solid content detection system and method for slurry

Abstract

The invention relates to an online solid content detection system and method for slurry. The device comprises a main pipeline, a bypass line; the first three-way valve is respectively connected with one end of the bypass pipeline, the main pipeline and the cleaning liquid pipeline; the second three-way valve is respectively connected with the other end of the bypass pipeline, the main pipeline and the waste liquid pipeline; the on-line densimeter is arranged on the bypass pipeline and is used for collecting the density value of the slurry in real time; the fourth control valve and the fifth control valve are arranged on the bypass pipeline and located on the two sides of the online densimeter respectively, and the fifth control valve is connected with the second three-way valve; the conveying pump is connected to the first three-way valve; the three-way pipe is arranged on the bypass pipeline and connected with the fourth control valve, the conveying pump and the third drain valve; the third drain valve is used for discharging residual cleaning waste liquid in the bypass pipeline after the cleaning process is finished; and the sixth control valve is arranged on the cleaning liquid pipeline and is used for controlling the on-off of the cleaning liquid. According to the invention, the detection accuracy and speed are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of slurry detection, and in particular to an online solid content detection system and method for slurry. Background Art

[0002] In the pulping, papermaking, chemical, food, and pharmaceutical industries, the solids content of slurry (i.e., the mass percentage of solid matter per unit volume of slurry) is a critical parameter affecting product quality and production efficiency. In actual production, changes in solids content often directly affect the performance of the final product and the stability of subsequent processes.

[0003] Therefore, during the pulping process, to ensure the quality of the finished pulp, regular sampling and testing of semi-finished or finished pulp and its solution is required. If the test results are abnormal, the relevant process parameters must be adjusted in a timely manner to ensure that the production process is under control and the final product meets the quality requirements.

[0004] However, existing testing methods generally rely on manual labor, requiring technicians to manually collect samples at the production site and then bring them back to the laboratory for analysis. This approach not only increases labor and operating costs but also easily results in slurry waste. Furthermore, due to the time delay associated with testing, real-time monitoring of the slurry's solids content is impossible, limiting the level of automation in the production process and making it difficult to meet the demands of efficient and precise production. Summary of the Invention

[0005] To this end, the present invention provides an online solid content detection system and method for slurry, which can realize automatic sampling and automatic detection of the slurry production line, and can perform automatic cleaning after the detection is completed, thereby improving the accuracy and speed of detection.

[0006] In order to solve the above technical problems, the present invention provides an online solid content detection system for slurry, comprising:

[0007] Main pipeline, used for conveying pulp in pulping production;

[0008] A bypass line, used to divert part of the slurry in the main line for online detection;

[0009] a first three-way valve, connected to one end of the bypass line, the main line, and the cleaning liquid line, respectively; the first three-way valve is capable of introducing slurry in the main line into the bypass line, and introducing cleaning liquid into the bypass line;

[0010] a second three-way valve, connected to the other end of the bypass line, the main line, and the waste liquid line, respectively; the second three-way valve is capable of returning the slurry from the bypass line to the main line and discharging the cleaning waste liquid to the waste liquid line;

[0011] An online density meter, provided on the bypass pipeline, for collecting the density value of the slurry in real time;

[0012] a fourth control valve and a fifth control valve, respectively provided on the bypass line and located on both sides of the online densitometer, the fifth control valve being connected to the second three-way valve;

[0013] a delivery pump connected to the first three-way valve;

[0014] a three-way pipe and a third liquid discharge valve, wherein the three-way pipe is arranged on the bypass pipeline and is respectively connected to the fourth control valve, the delivery pump and the third liquid discharge valve; the third liquid discharge valve is used to discharge the residual cleaning waste liquid in the bypass pipeline after the cleaning process is completed;

[0015] The sixth control valve is provided on the cleaning fluid pipeline and is used to control the on-off of the cleaning fluid.

[0016] In one embodiment of the present invention, a controller is further included, and the first three-way valve, the second three-way valve, the third liquid discharge valve, the fourth control valve, the fifth control valve, the sixth control valve, the delivery pump and the online density meter are all electrically connected to the controller.

[0017] In one embodiment of the present invention, the controller comprises a PLC controller.

[0018] In one embodiment of the present invention, a host computer is further included, which is communicatively connected to the controller and is used to receive a plurality of slurry density sampling values collected by the online densitometer and transmitted by the controller, and calculate the density average value based on the plurality of slurry density sampling values. The host computer calculates the corresponding slurry solid content value based on the density average value and in combination with a preset relationship model between slurry density and solid content.

[0019] In one embodiment of the present invention, the slurry density and solid content are in a linear relationship, that is, they satisfy the following mathematical model:

[0020] Y=kX+B

[0021] Where Y represents the solid content of the slurry, X represents the average density collected by the online densitometer, k is the proportional coefficient, and B is the intercept. k and B can be fitted based on multiple groups of slurry samples with known density and corresponding solid content.

[0022] In one embodiment of the present invention, the first three-way valve, the second three-way valve, the third drain valve, the fourth control valve, the fifth control valve, and the sixth control valve all include ball valves.

[0023] In one embodiment of the present invention, the installation position of the delivery pump is higher than the installation position of the third liquid discharge valve.

[0024] In one embodiment of the present invention, the installation position of the bypass line is higher than the installation position of the third liquid discharge valve.

[0025] The present invention also provides a method for detecting the online solid content of a slurry, based on the online solid content detection system of the slurry, comprising:

[0026] Step S1: Controlling and opening the delivery pump, and switching the first three-way valve and the second three-way valve to connect with the main line, then opening the fourth control valve and the fifth control valve, so that the slurry in the main line enters the bypass line through the first three-way valve, flows through the online densitometer, and then returns to the main line from the second three-way valve;

[0027] Step S2: Slurry density values are collected by an online densitometer, and the collection is performed at a predetermined frequency within a predetermined duration to obtain a plurality of slurry density sampling values. The host computer calculates a density average value based on the plurality of slurry density sampling values. According to the density average value and in combination with a preset relationship model between slurry density and solid content, a corresponding slurry solid content value is calculated, wherein the slurry density and solid content conform to a linear relationship;

[0028] Step S3: After density collection is completed, the bypass pipeline is automatically cleaned.

[0029] In one embodiment of the present invention, automatically cleaning the bypass line includes:

[0030] Step S3-1: Controlling the opening of the sixth control valve, switching the first three-way valve to connect to the cleaning liquid pipeline, switching the second three-way valve to connect to the waste liquid pipeline, and simultaneously controlling the opening of the delivery pump, the fourth control valve, and the fifth control valve to allow the cleaning liquid to continuously flow through the bypass pipeline to flush the bypass pipeline;

[0031] Step S3-2: After the flushing is completed, the sixth control valve is controlled to close and the third drain valve is opened to allow the waste liquid remaining in the bypass pipeline to be discharged through the third drain valve after the cleaning process, and then the delivery pump and the third drain valve are closed.

[0032] The above technical solution of the present invention has the following advantages over the prior art:

[0033] The present invention discloses an online solid content detection system and method for slurry. By connecting a bypass line to the main line, slurry in the production process can continuously flow through the bypass line, ensuring fresh slurry is obtained. This system and method also allows for cleaning the inner wall of the main line using a ball pusher or other mechanical contact methods. While the ball pusher is cleaning the main line, the bypass sampling line can be flushed with a solution by switching the three-way valve on the bypass line, preventing slurry residue in the bypass line, which could cause cross-contamination of the sampled material. This system enables automatic sampling and detection results for the slurry production line. After the test is complete, automatic cleaning is performed, shortening the test time and improving the test accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to make the contents of the present invention more clearly understood, the present invention is further described in detail below based on specific embodiments of the present invention in conjunction with the accompanying drawings.

[0035] Figure 1 It is a schematic diagram of the principle structure of the online solid content detection system of the slurry of the present invention.

[0036] Figure 2 It is a schematic diagram of the axial side structure of the online solid content detection system of the slurry of the present invention.

[0037] Figure 3 It is a fitting diagram of the relationship between density value and solid content.

[0038] Description of the accompanying drawings:

[0039] 100, main line; 200, bypass line; 300, online densitometer; 400, cleaning liquid line; 500, waste liquid line; 101, first three-way valve; 102, second three-way valve; 103, third drain valve; 104, fourth control valve; 105, fifth control valve; 106, sixth control valve; 107, three-way pipe; 108, delivery pump. DETAILED DESCRIPTION

[0040] The present invention will be further described below with reference to the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it. However, the embodiments are not intended to limit the present invention.

[0041] In the present invention, if directions (up, down, left, right, front and back) are described, it is only for the convenience of describing the technical solution of the present invention, and does not indicate or imply that the technical features referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, it cannot be understood as a limitation of the present invention.

[0042] In the present invention, "several" means one or more, "multiple" means more than two, "greater than," "less than," "exceeds," etc. are understood to exclude the number itself; "above," "below," "within," etc. are understood to include the number itself. In the description of the present invention, the use of "first" or "second" is solely for the purpose of distinguishing technical features and is not to be construed as indicating or implying relative importance, implicitly specifying the number of the indicated technical features, or implicitly specifying the order of the indicated technical features.

[0043] In the present invention, unless otherwise expressly defined, terms such as "disposed," "installed," and "connected" should be interpreted broadly. For example, they may refer to direct connection or indirect connection through an intermediate medium; fixed connection or detachable connection or integral molding; mechanical connection or electrical connection or mutual communication; and internal connection between two components or interaction between two components. Those skilled in the art can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0044] Example 1

[0045] Reference Figure 1 As shown, this embodiment provides an online solid content detection system for slurry, comprising:

[0046] The main pipeline 100 is used to transport the pulp in pulping production;

[0047] The bypass line 200 is used to drain part of the slurry in the main line 100 for online detection;

[0048] A first three-way valve 101 is connected to one end of the bypass line 200, the main line 100, and the cleaning liquid line 400, respectively; the first three-way valve 101 can introduce the slurry in the main line 100 into the bypass line 200, and introduce the cleaning liquid into the bypass line 200;

[0049] A second three-way valve 102 is connected to the other end of the bypass line 200, the main line 100, and the waste liquid line 500, respectively. The second three-way valve 102 can return the slurry from the bypass line 200 to the main line 100 and discharge the cleaning waste liquid to the waste liquid line 500.

[0050] An online density meter 300 is provided on the bypass line 200 and is used to collect the density value of the slurry in real time;

[0051] The fourth control valve 104 and the fifth control valve 105 are respectively provided on the bypass line 200 and located on both sides of the online densitometer 300. The fifth control valve 105 is connected to the second three-way valve 102.

[0052] a delivery pump 108 connected to the first three-way valve 101;

[0053] A three-way pipe 107 and a third drain valve 103 are provided on the bypass line 200 and are connected to the fourth control valve 104, the delivery pump 108, and the third drain valve 103, respectively. The third drain valve 103 is used to discharge residual cleaning waste liquid in the bypass line 200 after the cleaning process is completed.

[0054] The sixth control valve 106 is provided on the cleaning fluid pipeline 400 and is used to control the on-off flow of the cleaning fluid.

[0055] Specifically, it also includes a controller, and the first three-way valve 101, the second three-way valve 102, the third liquid discharge valve 103, the fourth control valve 104, the fifth control valve 105, the sixth control valve 106, the delivery pump 108 and the online density meter 300 are all electrically connected to the controller.

[0056] Specifically, the controller includes a PLC controller.

[0057] Specifically, it also includes a host computer, which is communicatively connected to the controller and is used to receive a plurality of slurry density sampling values collected by the online densitometer 300 and transmitted by the controller, and calculate the density average value based on the plurality of slurry density sampling values. The host computer calculates the corresponding slurry solid content value based on the density average value and in combination with a preset relationship model between slurry density and solid content.

[0058] The online densitometer 300 collects slurry density values at a predetermined frequency over a predetermined duration to obtain multiple slurry density sampling values. In this embodiment, the sampling period lasts for 2 minutes, with one sampling value taken every 3 seconds. It is understood that the PLC controller establishes a data connection with the host computer via an industrial communication protocol, which transmits the collected density data output by the online densitometer 300 to the host computer periodically or in an event-triggered manner. The communication method can be an industrial communication interface such as Ethernet, RS485, CAN bus, or Modbus protocol. After receiving the density data, the host computer calculates and displays the solids content of the slurry in real time based on a preset mathematical model.

[0059] It should be noted that through in-depth research on the physical properties of slurries, it was discovered that there is a close correlation (a linear relationship) between the density and solids content of slurries. Based on this, several representative slurry samples were selected and their density values were accurately measured using an online densitometer 300, and the corresponding solids content values were simultaneously determined.

[0060] There is a linear relationship between slurry density and solid content, which satisfies the following mathematical model:

[0061] Y=kX+B

[0062] Wherein, Y represents the solid content of the slurry, unit: %, and X represents the average density collected by the online density meter 300, unit: g / cm 3 , k is the proportional coefficient, B is the intercept, k and B can be fitted based on multiple groups of slurry samples with known density and corresponding solid content.

[0063] With the above setup, the online densitometer 300 monitors the slurry's density in real time and rapidly transmits this real-time data to the host computer. Using an established mathematical model, the host computer instantly processes and analyzes the received density data, directly predicting the slurry's solids content in real time. This real-time, accurate prediction method enables production personnel to promptly monitor the dynamic changes in the slurry's solids content, providing strong support for precise control of the production process.

[0064] Specifically, refer to Figure 2 As shown, the first three-way valve 101 , the second three-way valve 102 , the third drain valve 103 , the fourth control valve 104 , the fifth control valve 105 and the sixth control valve 106 all include ball valves.

[0065] Specifically, the installation position of the delivery pump 108 is higher than that of the third drain valve 103; and the installation position of the bypass line 200 is higher than that of the third drain valve 103. This facilitates the drainage of cleaning waste liquid from the third drain valve 103 under the action of gravity, preventing cross contamination caused by residual liquid stagnation. It is understood that "installation position higher" means being arranged above the installation reference plane (e.g., the support structure base of the entire detection system or the centerline of the main line 100) in the direction of gravity, with a positive vertical distance difference.

[0066] It should be noted that during the production process, the first three-way valve 101 is opened and connected to the main line 100, and the slurry is introduced into the bypass line 200; the slurry passes through the online density meter 300 under the drive of the delivery pump 108, and flows back to the main line 100 from the second three-way valve 102; the online density meter 300 collects the slurry density value at a fixed period under the control of the controller, and uploads the data to the host computer through the PLC; the host computer calculates the solid content of the slurry in real time based on the collected density average value and the preset linear model Y=kX+B; after the detection is completed, the system switches to the cleaning mode, and the controller controls the operation of each valve and the delivery pump 108 to make the cleaning liquid flow through the bypass line 200 to remove the residual slurry, and finally opens the third drain valve 103 to discharge the waste liquid, completing a complete detection and cleaning cycle.

[0067] Example 2

[0068] This embodiment provides a method for detecting the online solid content of a slurry, based on the online solid content detection system for the slurry described in Example 1, comprising:

[0069] Step S1: (via the controller) controlling the delivery pump 108 to open, and switching the first three-way valve 101 and the second three-way valve 102 to connect with the main line 100, then opening the fourth control valve 104 and the fifth control valve 105, so that the slurry in the main line 100 enters the bypass line 200 through the first three-way valve 101, flows through the online densitometer 300, and then returns to the main line 100 from the second three-way valve 102;

[0070] Step S2: The slurry density value is collected by the online densitometer 300, and the collection is performed at a predetermined frequency within a predetermined duration to obtain a plurality of the slurry density sampling values; in this embodiment, the collection lasts for 2 minutes, and the value is read once every 3 seconds; the upper computer calculates the density average value based on the plurality of the slurry density sampling values, and calculates the corresponding slurry solid content value according to the density average value and in combination with a preset relationship model between the slurry density and the solid content, wherein the slurry density and the solid content conform to a linear relationship.

[0071] This embodiment uses lithium battery slurry as a research object, the solid content of the slurry ranges from 50% to 55%, and performs experimental verification under predetermined temperature conditions (eg, room temperature 25° C.).

[0072] First, we selected several lithium battery slurry samples with varying solid contents and measured their actual solids content using the oven method. We also measured their density using an online densitometer. The resulting validation and modeling data are shown in Table 1 below.

[0073] Table 1: Verification data and modeling data table

[0074]

[0075] The first 7 groups of samples were used as modeling samples to establish the density value (g / cm 3 ) and solid content (%). Through regression analysis, the corresponding data of density value and solid content are processed, and the corresponding data of density value and solid content are processed. Figure 3 As shown. The following linear fitting relationship is obtained:

[0076] Y=83.298X-63.919

[0077] R 2 =0.9994

[0078] Where Y represents the solid content (%), X represents the density (g / cm 3 ), the coefficient of determination R of linear regression fitting2 =0.9994, indicating that there is a high linear correlation between density value and solid content.

[0079] To verify the applicability of the model, 9 groups of independent verification samples were selected, and the density values obtained from their online detection were substituted into the above model to calculate the solid content and compare it with the actual solid content measured by the laboratory oven method. Specifically, the online detection system of this embodiment was used to monitor the actual production line slurry in real time, and the solid content values detected online were compared with the solid content measured by the traditional oven method. The results showed that the deviation range between the two was controlled between -0.28% and +0.24%, which met the set process control accuracy target of ±0.5%, indicating that the relationship model between density and solid content constructed has good accuracy and feasibility.

[0080] Step S3: After density collection is completed, the PLC controller starts the detection program to automatically clean the bypass pipeline 200. Specifically, it includes:

[0081] Step S3-1: Controlling the opening of the sixth control valve 106, switching the first three-way valve 101 to connect to the cleaning liquid pipeline 400, switching the second three-way valve 102 to connect to the waste liquid pipeline 500, and simultaneously controlling the opening of the delivery pump 108, the fourth control valve 104, and the fifth control valve 105 to allow the cleaning liquid to continuously flow through the bypass pipeline 200 to flush the bypass pipeline 200;

[0082] Step S3-2: After the flushing is completed, the sixth control valve 106 is controlled to be closed, and the third drain valve 103 is opened, so that the waste liquid remaining in the bypass pipeline 200 after the cleaning process is completed is discharged through the third drain valve 103, and then the delivery pump 108 and the third drain valve 103 are closed.

[0083] This method overcomes the limitations of traditional sampling and testing, eliminating the need to sample large quantities of slurry from the production process and send them to the laboratory for solids content testing. By performing online testing on bypass line 200, the slurry solids content can be monitored in real time without disrupting the normal production process.

[0084] In addition, after the test is completed, the system can perform an automatic cleaning procedure. Slurry residue is a common and difficult problem in industrial production. If slurry remains in the bypass line 200, it will not only affect the accuracy of subsequent tests, but may also cause failures such as pipeline blockage, increasing maintenance costs and downtime. The automatic cleaning function can completely remove slurry residue in the bypass line 200, greatly improving the accuracy of the test and the reliability of the system. At the same time, the automatic cleaning process does not require excessive human intervention, further improving detection efficiency and reducing the errors and time costs caused by manual operation.

[0085] Finally, it should be noted that the above specific implementation methods are only used to illustrate the technical solutions of the present invention and are not limiting. Although the present invention has been described in detail with reference to examples, those skilled in the art should understand that the technical solutions of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. An online solid content detection system for slurry, characterized in that: include: The main pipeline (100) is used for conveying pulp in pulping production; A bypass line (200) is used to drain part of the slurry in the main line (100) for online detection; a first three-way valve (101) connected to one end of the bypass pipeline (200), the main pipeline (100), and the cleaning liquid pipeline (400), respectively; the first three-way valve (101) is capable of introducing slurry in the main pipeline (100) into the bypass pipeline (200), and introducing cleaning liquid into the bypass pipeline (200); a second three-way valve (102) connected to the other end of the bypass line (200), the main line (100), and the waste liquid line (500), respectively; the second three-way valve (102) can allow the slurry to flow back from the bypass line (200) to the main line (100), and discharge the cleaning waste liquid to the waste liquid line (500); An online density meter (300) is provided on the bypass line (200) and is used to collect the density value of the slurry in real time; a fourth control valve (104) and a fifth control valve (105), respectively provided on the bypass line (200) and located on both sides of the online densitometer (300); the fifth control valve (105) is connected to the second three-way valve (102); a delivery pump (108), connected to the first three-way valve (101); a three-way pipe (107) and a third liquid discharge valve (103), wherein the three-way pipe (107) is arranged on the bypass pipeline (200) and is respectively connected to the fourth control valve (104), the delivery pump (108) and the third liquid discharge valve (103); the third liquid discharge valve (103) is used to discharge residual cleaning waste liquid in the bypass pipeline (200) after the cleaning process is completed; The sixth control valve (106) is provided on the cleaning liquid pipeline (400) and is used to control the on-off flow of the cleaning liquid.

2. The online solid content detection system for slurry according to claim 1, characterized in that: The invention also includes a controller, wherein the first three-way valve (101), the second three-way valve (102), the third liquid discharge valve (103), the fourth control valve (104), the fifth control valve (105), the sixth control valve (106), the delivery pump (108) and the online density meter (300) are all electrically connected to the controller.

3. The online solid content detection system for slurry according to claim 2, characterized in that: The controller includes a PLC controller.

4. The online solid content detection system for slurry according to claim 1, characterized in that: The system further comprises a host computer, which is in communication with the controller and is used to receive a plurality of slurry density sampling values collected by the online density meter (300) and transmitted by the controller, and calculate a density average value based on the plurality of slurry density sampling values. The host computer calculates a corresponding slurry solid content value based on the density average value and in combination with a preset relationship model between slurry density and solid content.

5. The online solid content detection system for slurry according to claim 4, characterized in that: There is a linear relationship between slurry density and solid content, which satisfies the following mathematical model: Y=kX+B, in, Y Indicates the solid content of the slurry, X represents the average density value collected by the online density meter (300), k is the proportionality coefficient, B is the intercept, k and B It can be obtained by fitting multiple groups of slurry samples with known density and corresponding solid content.

6. The online solid content detection system for slurry according to claim 1, characterized in that: The first three-way valve (101), the second three-way valve (102), the third drain valve (103), the fourth control valve (104), the fifth control valve (105), and the sixth control valve (106) all comprise ball valves.

7. The online solid content detection system for slurry according to claim 1, characterized in that: The installation position of the delivery pump (108) is higher than the installation position of the third liquid discharge valve (103).

8. The online solid content detection system for slurry according to claim 1 or 7, characterized in that: The installation position of the bypass pipeline (200) is higher than the installation position of the third liquid discharge valve (103).

9. A method for detecting the online solid content of a slurry, based on the online solid content detection system of the slurry according to any one of claims 1 to 8, characterized in that: include: Step S1: Controlling and opening the delivery pump (108), and switching the first three-way valve (101) and the second three-way valve (102) to communicate with the main line (100), and then opening the fourth control valve (104) and the fifth control valve (105), so that the slurry in the main line (100) enters the bypass line (200) through the first three-way valve (101), flows through the online density meter (300), and then returns to the main line (100) from the second three-way valve (102); Step S2: Slurry density values are collected by an online densitometer (300), and the collection is performed at a predetermined frequency within a predetermined duration to obtain a plurality of slurry density sampling values. The host computer calculates a density average value based on the plurality of slurry density sampling values. According to the density average value and in combination with a preset relationship model between slurry density and solid content, a corresponding slurry solid content value is calculated, wherein the slurry density and solid content conform to a linear relationship. Step S3: After density collection is completed, the bypass pipeline (200) is automatically cleaned.

10. The method for online solid content detection of slurry according to claim 9, characterized in that: Automatically cleaning the bypass line (200) includes: Step S3-1: Controlling the opening of the sixth control valve (106), switching the first three-way valve (101) to communicate with the cleaning liquid pipeline (400), switching the second three-way valve (102) to communicate with the waste liquid pipeline (500), and simultaneously controlling the opening of the delivery pump (108), the fourth control valve (104), and the fifth control valve (105), so that the cleaning liquid continuously flows through the bypass pipeline (200) to flush the bypass pipeline (200); Step S3-2: After the flushing is completed, the sixth control valve (106) is controlled to be closed, and the third drain valve (103) is opened, so that the waste liquid remaining in the bypass pipeline (200) after the cleaning process is discharged through the third drain valve (103), and then the delivery pump (108) and the third drain valve (103) are closed.

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