A method and installation for detecting the discharge of a continuous crystallization separation effect

Abstract

The application discloses a method and facility for detecting discharging of continuous crystallization separation effect, and relates to the technical field of chemical evaporation crystallization, and comprises the following steps: S1, starting a peristaltic pump and a sampling control valve arranged in a discharging area; S2, returning separated concentrated solid and clear liquid to an evaporation crystallization device; S3, measuring the flow of the separated clear liquid by using a flow meter; S4, calculating the solid-liquid separation effect in a thickener; and S5, comparing the calculated solid-liquid separation effect with a preset setting value range by using a controller. The application eliminates fluctuation problems, effectively avoids blockage of a discharging port, guarantees production continuity, realizes the change from "after adjustment" to "prior prediction", overcomes the limitation of single-point sampling, realizes closed-loop circulation in the whole sampling, analysis and return process, and eliminates the safety risks such as pollution, scalding and harmful substance emission existing in traditional open sampling, and realizes the whole-system collaborative optimization.

Description

Technical Field

[0001] This invention relates to the field of chemical evaporation and crystallization technology, and in particular to a method and facility for continuous crystallization separation effect detection and discharge. Background Technology

[0002] Continuous evaporation crystallization technology is a widely used separation and purification method in chemical, pharmaceutical, food, and wastewater treatment industries. Its basic principle is to continuously feed the raw material solution or mother liquor to be crystallized into the evaporation crystallization equipment. By heating and evaporating to remove some of the solvent or changing the crystallization conditions (such as cooling or concentration), the solution reaches a supersaturated state, and crystals precipitate, yielding crystalline material. Compared to traditional batch crystallization operations, continuous crystallization has significant advantages such as high production efficiency, stable product quality, and small batch-to-batch variations, making it an important development direction for current chemical process intensification and intelligent manufacturing. In a typical continuous evaporation crystallization production process, the evaporation crystallization equipment has a discharge port at the bottom. The crystallized slurry (a mixture of solids and mother liquor) is released downstream via a discharge valve. It typically undergoes preliminary solid-liquid separation and concentration in a hydrocyclone or thickener before being sent to a centrifuge for dehydration and drying to obtain the final product. The discharge port of the evaporation crystallization equipment is usually just a single on / off valve that opens or closes upon receiving a discharge signal. While the operation is simple, it has several shortcomings in actual operation: First, the existing discharge method involves both water and material simultaneously. The timing of discharge is problematic. Firstly, the material initially contains a high amount of solids, while the solids content gradually decreases later. This significant fluctuation in the solid-liquid ratio causes deviations in the separation coefficient of downstream dewatering equipment, severely impacting subsequent dewatering efficiency. Secondly, the timing of opening or closing the discharge valve relies heavily on operator experience, on-site observation via a sight glass, and manual sampling and testing. Since manual observation is subjective and time-consuming, and sampling and testing require analysis time, discharge operations are often initiated too early or too late. When discharge is initiated too early, the crystals in the material have not yet fully formed. Long discharge times and low solid content not only reduce the processing efficiency of downstream equipment, but may also cause a large amount of fine crystals to enter the mother liquor circulation system, affecting the normal operation of the crystallizer. When the discharge is too late, the material is over-concentrated in the crystallizer, and the solid content of the discharged material is too high and fluctuates drastically, which brings great difficulties to the downstream dehydration and separation. Furthermore, if the crystallization rate in the crystallizer is too fast and the on-site operators fail to detect it in time, the discharge time will be seriously delayed, which will easily cause blockage of the discharge port and pipeline. Once a blockage occurs, it is often necessary to stop the machine for cleaning, which seriously affects the continuity of production and the operating efficiency of the equipment.

[0003] However, current common solutions have many drawbacks, including: in continuous evaporation crystallization production, the discharge port is usually only equipped with a switch valve, and the "water and material together" discharge method leads to large fluctuations in the solid-liquid ratio, which seriously affects the downstream dehydration and separation efficiency; the timing of discharge depends on manual experience and sampling analysis, which is subject to lag and subjectivity, and too early or too late will affect the crystal quality and the operation of subsequent equipment; if the crystallization speed is too fast and not detected in time, it is easy to cause blockage of the discharge port, resulting in shutdown for cleaning; the solid-liquid ratio and crystal particle size distribution in different areas of the crystallizer are very different, and traditional single-point sampling is difficult to fully reflect the crystallization state of each area; open manual sampling also poses safety risks such as material contamination and personnel burns and chemical burns; in addition, the measurement of solid content takes a long time, and the material pump is difficult to adjust the flow rate quickly according to the change of solid-liquid ratio, resulting in a mismatch between downstream equipment and the incoming material state, further reducing the separation efficiency. Summary of the Invention

[0004] The purpose of this section is to outline some aspects of embodiments of the present invention and to briefly describe some preferred embodiments. Simplifications or omissions may be made in this section, as well as in the abstract and title of this application, to avoid obscuring the purpose of these documents; however, such simplifications or omissions should not be construed as limiting the scope of the invention.

[0005] In view of the problems existing in the current continuous crystallization separation effect detection and feeding method and facility, the present invention is proposed.

[0006] Therefore, the purpose of this invention is to provide a method and facility for continuous crystallization separation effect detection and discharge, which is applicable to solving the problems in continuous evaporation crystallization production where the discharge port is usually only equipped with a switch valve, and the "water and material together" discharge method leads to large fluctuations in the solid-liquid ratio, which seriously affects the downstream dehydration and separation efficiency; the timing of discharge depends on manual experience and sampling analysis, which is lagging and subjective, and too early or too late will affect the crystal quality and subsequent equipment operation; if the crystallization speed is too fast and not detected in time, it is easy to cause blockage of the discharge port, resulting in shutdown and cleaning; the solid-liquid ratio and crystal particle size distribution in different areas of the crystallizer are very different, and traditional single-point sampling is difficult to fully reflect the crystallization state of each area; open manual sampling also poses safety risks such as material contamination and personnel burns and chemical burns; in addition, the measurement of solid content is time-consuming, and the material pump is difficult to quickly adjust the flow rate according to the change of solid-liquid ratio, resulting in a mismatch between downstream equipment and incoming material state, further reducing the separation efficiency.

[0007] To solve the above-mentioned technical problems, the present invention provides the following technical solution: In a first aspect, embodiments of the present invention provide a continuous crystallization separation effect detection and discharge method, comprising: S1: when crystallization occurs in the evaporation crystallization equipment, activating a peristaltic pump and a sampling control valve located in the discharge area, extracting a material sample from the discharge area via the peristaltic pump, and setting the flow rate of the peristaltic pump to match the flow rate of the production line discharge pump to simulate the flow rate of the discharge pump during operation; S2: conveying the extracted material sample to a thickener for solid-liquid separation, and returning the separated concentrated solids and clear liquid to the evaporation crystallization equipment respectively; S3: The flow rate of the separated clear liquid is measured by a flow meter, and the clear liquid flow rate data is fed back to the controller; S4: The controller calculates the solid-liquid separation effect in the thickener based on the set flow rate of the peristaltic pump and the clear liquid flow rate fed back by the flow meter; S5: The controller compares the calculated solid-liquid separation effect with a preset set value range. If the calculated value is within the set value range, the controller controls the discharge valve to open and discharge the material; if the calculated value exceeds the set value range, the controller controls the discharge valve to remain closed or closes the opened discharge valve to stop discharging the material.

[0008] As a preferred embodiment of the continuous crystallization separation effect detection and feeding method of the present invention, in step S4, the controller calculates the solid-liquid separation effect by subtracting the clear liquid flow rate fed back by the flow meter from the set flow rate of the peristaltic pump, and the difference is used as the quantitative value of the solid-liquid separation effect.

[0009] As a preferred embodiment of the continuous crystallization separation effect detection and feeding method of the present invention, wherein: when the difference is greater than the upper limit of the set numerical range, it is determined that the solid content of the sampled material is too low or the separation flow rate is too slow; when the difference is less than the lower limit of the set numerical range, it is determined that the solid content of the sampled material is too high or the separation flow rate is too fast.

[0010] As a preferred embodiment of the continuous crystallization separation effect detection and feeding method of the present invention, the thickener is a cyclone separator, whose length-to-diameter ratio is the same as that of the thickener already configured on the production line, and the size is reduced by the same proportion.

[0011] As a preferred embodiment of the continuous crystallization separation effect detection feeding method of the present invention, the feeding area is multiple, and each feeding area is connected to the peristaltic pump through an independent sampling control valve. The controller selectively opens the sampling control valves of different areas to realize the sampling and analysis of materials in multiple feeding areas and obtain multi-area distribution data.

[0012] As a preferred embodiment of the continuous crystallization separation effect detection and discharge method of the present invention, the controller, while controlling the opening or closing of the discharge valve, also controls the switching and speed adjustment of the production line discharge pump according to the calculation results of the solid-liquid separation effect.

[0013] As a preferred embodiment of the continuous crystallization separation effect detection and discharge method of the present invention, the peristaltic pump is a peristaltic pump with flow regulation function, and its flow setting value is infinitely adjusted according to the normal flow range of the discharge pump to simulate the separation effect under different flow rates.

[0014] Secondly, to further solve the above-mentioned technical problems, the present invention provides a continuous crystallization separation effect detection and discharge facility, which includes: a peristaltic pump for extracting material samples from the discharge area of ​​the evaporation crystallization equipment and precisely controlling the flow rate; a thickener connected to the outlet of the peristaltic pump for solid-liquid separation of the material sample transported by the peristaltic pump; a flow meter connected to the clear liquid outlet of the thickener for measuring the flow rate of the clear liquid separated by the thickener; a controller connected to the flow meter, the peristaltic pump and the discharge valve respectively, for calculating the solid-liquid separation effect based on the flow rate of the peristaltic pump and the clear liquid flow rate fed back by the flow meter, and controlling the opening or closing of the discharge valve according to the calculation result; and a discharge valve installed on the discharge pipeline of the evaporation crystallization equipment and connected to the controller for performing the discharge operation according to the control signal of the controller.

[0015] As a preferred embodiment of the continuous crystallization separation effect detection and discharge facility of the present invention, at least one control valve is provided on the pipeline between different discharge areas of the evaporation crystallization equipment and the peristaltic pump, and is signal-connected to the controller, for selectively opening or closing according to the control signal of the controller, so as to sample and analyze the material in different areas.

[0016] As a preferred embodiment of the continuous crystallization separation effect detection and discharge facility of the present invention, the concentrated solids outlet and the clear liquid outlet of the thickener are respectively returned to the evaporation crystallization equipment through pipelines.

[0017] The beneficial effects of this invention are as follows: This invention employs a technical approach of "micro-sampling, proportional simulation, differential quantification, threshold comparison, and automatic discharge," precisely quantifying the solid-liquid separation effect by subtracting the clear liquid flow rate from the set flow rate of the peristaltic pump. This replaces traditional manual judgment and achieves precise automatic control of the discharge timing. The "discharge when qualified, stop when unqualified" mechanism ensures the continuous stability of the solid-liquid ratio during discharge, eliminating fluctuations and maintaining a stable separation coefficient in downstream dewatering equipment, significantly improving dewatering efficiency. The facility can promptly stop discharging based on abnormal separation results, effectively preventing discharge port blockage and ensuring production continuity. By using a thickener with the same length-to-diameter ratio as the production line and proportionally scaled down, combined with a peristaltic pump to simulate the discharge pump flow rate, this invention possesses a pilot-type simulation and prediction function, achieving precise automatic control of the discharge timing with minimal material consumption. This invention enables the prediction of separation results on the production line, shifting from "post-event adjustment" to "pre-event prediction." Multiple sampling control valves allow for the detection of the distribution of crystallization states in different areas within the crystallizer, overcoming the limitations of single-point sampling. The entire sampling, analysis, and return process is a closed-loop cycle, preventing material contact with the outside environment and eliminating safety risks associated with traditional open sampling, such as contamination, burns, and the release of harmful substances. Furthermore, the invention can adjust the discharge pump speed based on the detection results and provide feedforward control signals to downstream equipment, connecting upstream crystallization, midstream detection, and downstream separation into a coordinated whole, achieving system-wide optimization. In addition, the invention has a simple structure, is easy to install, and can be independently installed in existing equipment, making it suitable for various new construction and expansion projects, with broad application prospects. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Wherein: Figure 1 This is a flowchart illustrating the implementation of the present invention in Example 1.

[0019] Figure 2 This is the dynamic adjustment diagram in Example 1. Detailed Implementation

[0020] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0021] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0022] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments.

[0023] Example 1 Reference Figure 1 and Figure 2 This is the first embodiment of the present invention, which provides a continuous crystallization separation effect detection and feeding method, including the following steps: S1: When crystallization occurs in the evaporation crystallization equipment, turn on the peristaltic pump 1-1 and the sampling control valve 1-5 located in the discharge area. The peristaltic pump 1-1 extracts material samples from the discharge area, and the flow rate of the peristaltic pump 1-1 is set to match the flow rate of the production line discharge pump to simulate the flow rate of the discharge pump during operation.

[0024] Preferably, there are multiple material discharge areas, and each material discharge area is connected to the peristaltic pump 1-1 through an independent sampling control valve 1-5. The controller 1-2 selectively opens the sampling control valve 1-5 of different areas to realize the sampling and analysis of materials in multiple material discharge areas and obtain multi-area distribution data.

[0025] Furthermore, the peristaltic pump 1-1 is a peristaltic pump with flow regulation function. Its flow rate setting value is steplessly adjusted according to the normal flow range of the discharge pump to simulate the separation effect under different flow rates.

[0026] Furthermore, the sampling control valve 1-5 is an electric or pneumatic switching valve, and its opening and closing are controlled by the electrical or pneumatic signal output by the controller 1-2. The peristaltic pump 1-1 generates a suction effect by alternately squeezing the hose with its own rollers, and extracts the material sample from the discharge area. Since the flow rate of the peristaltic pump is linearly related to the roller speed, the flow rate can be accurately controlled by adjusting the motor speed.

[0027] S2: The extracted material sample is transported to thickener 1-3 for solid-liquid separation. The separated concentrated solids and clear liquid are returned to the evaporation and crystallization equipment respectively.

[0028] Preferably, the thickeners 1-3 are cyclone separators, with the same length-to-diameter ratio as the thickeners already configured on the production line, and their size is reduced by the same proportion.

[0029] Specifically, the thickener 1-3 is a small hydrocyclone separator made of stainless steel. It has a tangential feed inlet, an overflow pipe (clear liquid outlet) and a bottom outlet (concentrated solids outlet). After being pressurized by the peristaltic pump 1-1, the material sample enters the thickener 1-3 tangentially. Under the action of centrifugal force, the denser solids move towards the wall and are discharged downward from the bottom outlet, while the less dense clear liquid moves towards the center and is discharged upward from the overflow pipe.

[0030] Furthermore, the underflow port of the thickener 1-3 is connected to the discharge area or crystallization chamber of the evaporation crystallization equipment through a pipeline, and the overflow port of the thickener 1-3 is connected to the mother liquor area or clear liquor area of ​​the evaporation crystallization equipment through a pipeline, so that the separated concentrated solids and clear liquor are returned to the evaporation crystallization equipment respectively.

[0031] S3: Measure the flow rate of the separated clear liquid through flow meter 1-4 and feed the clear liquid flow rate data back to controller 1-2.

[0032] Preferably, the flow meters 1-4 are any one of electromagnetic flow meters, mass flow meters, or turbine flow meters, and have a 4-20mA or RS485 communication interface for transmitting the measured liquid flow data to the controller 1-2 in real time in the form of analog or digital signals.

[0033] Furthermore, the range of flow meter 1-4 is determined based on the maximum set flow rate of peristaltic pump 1-1, and its measurement accuracy is not less than ±0.5%.

[0034] Specifically, flow meter 1-4 is installed on the clear liquid outlet pipe of thickener 1-3. After the clear liquid flows out from the overflow pipe of thickener 1-3, it flows through flow meter 1-4. Flow meter 1-4 detects the flow rate of the clear liquid in real time and converts the flow data into an electrical signal and sends it to controller 1-2.

[0035] S4: The controller 1-2 calculates the solid-liquid separation effect in the thickener 1-3 based on the set flow rate of the peristaltic pump 1-1 and the clear liquid flow rate fed back by the flow meter 1-4.

[0036] Preferably, in step S4, the controller 1-2 calculates the solid-liquid separation effect by subtracting the clear liquid flow rate fed back by the flow meter 1-4 from the set flow rate of the peristaltic pump 1-1, and using the difference as the quantitative value of the solid-liquid separation effect.

[0037] Specifically, when the difference is greater than the upper limit of the set value range, it is determined that the solid content of the sampled material is too low or the separation flow rate is too slow; when the difference is less than the lower limit of the set value range, it is determined that the solid content of the sampled material is too high or the separation flow rate is too fast.

[0038] Furthermore, controller 1-2 is a programmable logic controller (PLC) or industrial computer, which has a preset value range for solid-liquid separation effect. Controller 1-2 is also equipped with a data storage module and a human-machine interface for recording historical detection data and allowing operators to view and modify the setting parameters.

[0039] S5: Controller 1-2 compares the calculated solid-liquid separation effect with the preset value range. If the calculated value is within the set value range, it controls the discharge valve 1-6 to open and discharge the material. If the calculated value exceeds the set value range, it controls the discharge valve 1-6 to remain closed or closes the already opened discharge valve and stops discharging the material.

[0040] Specifically, while controlling the opening or closing of the discharge valve 1-6, the controller 1-2 also controls the switching and speed adjustment of the production line discharge pump based on the calculation results of the solid-liquid separation effect.

[0041] Furthermore, the discharge valve 1-6 is an electric regulating valve or a pneumatic switching valve. After receiving the switching signal output by the controller 1-2, it performs a fully open or fully closed action. The controller 1-2 regulates the speed of the discharge pump of the production line through a frequency converter. The controller 1-2 outputs a 4-20mA analog signal to the frequency converter, and the frequency converter adjusts the operating frequency of the discharge pump motor according to the signal, thereby realizing stepless adjustment of the speed of the discharge pump.

[0042] The operation process of this invention is as follows: After the evaporation crystallization equipment is started, the material gradually concentrates in the equipment and begins to precipitate crystals. When the evaporation crystallization equipment reaches the theoretical time point for crystallization, the controller 1-2 automatically starts the peristaltic pump 1-1 according to the preset program, and sequentially or selectively opens the sampling control valves 1-5 set in each discharge area. Taking a single discharge area as an example: After controller 1-2 opens the sampling control valve 1-5 for that area, the material sample in that area enters peristaltic pump 1-1 through the sampling control valve 1-5 under the suction action of peristaltic pump 1-1. The flow rate of peristaltic pump 1-1 is set according to the normal flow rate range of the production line discharge pump, for example, the normal flow rate of the production line discharge pump is 10m³ / h. 3 / h, while the flow rate of peristaltic pump 1-1 is set to 100L / h and reduced by a ratio of 100:1 to simulate the flow rate of the discharge pump during operation; After being pressurized by peristaltic pump 1-1, the material sample enters thickener 1-3 tangentially. Under the action of centrifugal force, solid-liquid separation is achieved: the denser solid moves toward the wall of the container and is discharged downward from the bottom outlet, and returns to the crystallization chamber of the evaporation crystallization equipment through the pipeline; the less dense clear liquid moves toward the center and flows upward from the overflow pipe, and after being measured by flow meter 1-4, it returns to the mother liquor area of ​​the evaporation crystallization equipment through the pipeline. Flow meter 1-4 measures the flow rate of the clear liquid in real time and feeds back the flow data to controller 1-2 with a 4-20mA signal. Controller 1-2 subtracts the flow rate of the clear liquid fed back by flow meter 1-4 from the set flow rate of peristaltic pump 1-1. The difference is the quantitative value of the amount of solids separated in thickener 1-3. For example, if the set flow rate of peristaltic pump 1-1 is 100L / h, and the clear liquid flow rate fed back by flow meter 1-4 is 70L / h, then the difference is 30L / h, which means that at the current feed flow rate of 100L / h, the thickener separates solids equivalent to 30L / h. If the preset value range in controller 1-2 is 25~35L / h, then the current calculated value of 30L / h is within this range, indicating that the solid-liquid ratio of the material is in the appropriate range for discharge. Controller 1-2 compares the calculated solid-liquid separation effect quantification value with the preset set value range. If the calculated value is within the set value range, controller 1-2 outputs an open signal to discharge valve 1-6 and simultaneously outputs a start signal to the frequency converter of the production line discharge pump to start discharging. If the calculated value is lower than the lower limit of the set value range (e.g., the calculated value is 20L / h, which is lower than the lower limit of 25L / h), it indicates that the solid content in the sampled material is too low or the separation flow rate is too slow. Controller 1-2 keeps discharge valve 1-6 closed and does not discharge material temporarily. If the calculated value is higher than the upper limit of the set value range (e.g., the calculated value is 40L / h, which is higher than the upper limit of 35L / h), it indicates that the solid content in the sampled material is too high or the separation flow rate is too fast. Controller 1-2 also keeps discharge valve 1-6 closed or closes the opened discharge valve to stop discharging. During the material discharge process, controller 1-2 continuously performs the above sampling, detection and calculation. If the quantitative value of the solid-liquid separation effect is detected to deviate from the set value range, controller 1-2 immediately closes the discharge valve 1-6 and the discharge pump, stops the material discharge, and waits for the solid-liquid ratio of the material to return to a reasonable range before restarting the material discharge. When multiple material discharge areas need to be tested, the controller 1-2 opens the sampling control valves 1-5 of different areas in a preset order to sample and analyze the material in each area, obtain solid-liquid separation effect data of each area, and judge the crystallization state distribution of different areas in the crystallizer accordingly.

[0043] In summary, this invention employs a technical approach of "micro-sampling, proportional simulation, differential quantification, threshold comparison, and automatic discharge," precisely quantifying the solid-liquid separation effect by subtracting the clear liquid flow rate from the peristaltic pump's set flow rate. This replaces traditional manual judgment and achieves precise automatic control of the discharge timing. The "discharge when qualified, stop when unqualified" mechanism ensures a continuous and stable solid-liquid ratio during discharge, eliminating fluctuations and maintaining a stable separation coefficient in downstream dewatering equipment, significantly improving dewatering efficiency. The facility can promptly stop discharging based on abnormal separation results, effectively preventing discharge port blockage and ensuring production continuity. By using a thickener with the same length-to-diameter ratio as the production line and proportionally scaled down, combined with a peristaltic pump to simulate the discharge pump flow rate, this invention possesses a pilot-simulation prediction function, predicting production based on trace material consumption. The separation effect of the production line realizes the transformation from "post-event adjustment" to "pre-event prediction"; multiple sampling control valves can realize the distribution detection of crystallization state in different areas within the crystallizer, overcoming the limitations of single-point sampling; the entire sampling, analysis, and return process is a closed-loop cycle, with materials not coming into contact with the outside world, eliminating the safety risks such as pollution, burns, and release of harmful substances that exist in traditional open sampling; this invention can also adjust the discharge pump speed according to the detection results and provide feedforward control signals to downstream equipment, connecting upstream crystallization, midstream detection, and downstream separation into a coordinated whole, achieving system-wide synergistic optimization; in addition, this invention has a simple structure and is easy to install, and can be installed independently in existing equipment, making it suitable for various new construction and expansion projects, with broad prospects for promotion and application.

[0044] Example 2, an embodiment of the present invention, provides a continuous crystallization separation effect detection and discharge facility, comprising: a peristaltic pump 1-1, used to extract material samples from the discharge area of ​​the evaporation crystallization equipment and precisely control the flow rate; a thickener 1-3, connected to the outlet of the peristaltic pump 1-1, used to perform solid-liquid separation on the material sample conveyed by the peristaltic pump 1-1; a flow meter 1-4, connected to the clear liquid outlet of the thickener 1-3, used to measure the flow rate of the clear liquid separated by the thickener 1-3; a controller 1-2, signal-connected to the flow meter 1-4, the peristaltic pump 1-1 and the discharge valve 1-6 respectively, used to calculate the solid-liquid separation effect based on the flow rate of the peristaltic pump 1-1 and the clear liquid flow rate fed back by the flow meter 1-4, and control the opening or closing of the discharge valve 1-6 according to the calculation result; and the discharge valve 1-6, installed on the discharge pipeline of the evaporation crystallization equipment and signal-connected to the controller 1-2, used to perform the discharge operation according to the control signal of the controller 1-2.

[0045] Furthermore, at least one control valve 1-5 is installed on the pipeline between different discharge areas of the evaporation crystallization equipment and the peristaltic pump 1-1, and is signal-connected to the controller 1-2, for selectively opening or closing according to the control signal of the controller 1-2, so as to sample and analyze the material in different areas.

[0046] Specifically, the concentrated solids outlet and the clear liquid outlet of thickeners 1-3 are returned to the evaporation and crystallization equipment through pipelines.

[0047] Preferably, the hose of the peristaltic pump 1-1 is a silicone rubber hose, a fluororubber hose, or an EPDM rubber hose, and its inner diameter is selected according to the required flow range.

[0048] Furthermore, the signal connection between the controller 1-2 and the peristaltic pump 1-1, the flow meter 1-4, the sampling control valve 1-5, and the discharge valve 1-6 is either a wired cable connection or a wireless communication connection.

[0049] Specifically, the material pipeline is a stainless steel pipeline, the inner diameter of which matches the inner diameter of the hose of the peristaltic pump 1-1, and the pipeline connection uses a compression fitting or flange connection.

[0050] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A method for continuous crystallization separation effect detection and feeding, characterized in that: include: S1: When crystallization occurs in the evaporation crystallization equipment, turn on the peristaltic pump (1-1) and the sampling control valve (1-5) set in the discharge area. The peristaltic pump (1-1) extracts material samples from the discharge area and sets the flow rate of the peristaltic pump (1-1) to match the flow rate of the production line discharge pump to simulate the flow rate of the discharge pump during operation. S2: The extracted material sample is transported to the thickener (1-3) for solid-liquid separation. The separated concentrated solids and clear liquid are returned to the evaporation and crystallization equipment respectively. S3: Measure the flow rate of the separated clear liquid through the flow meter (1-4) and feed the clear liquid flow rate data back to the controller (1-2). S4: The controller (1-2) calculates the solid-liquid separation effect in the thickener (1-3) based on the set flow rate of the peristaltic pump (1-1) and the clear liquid flow rate fed back by the flow meter (1-4); S5: The controller (1-2) compares the calculated solid-liquid separation effect with a preset set value range. If the calculated value is within the set value range, the controller controls the discharge valve (1-6) to open and discharge the material. If the calculated value exceeds the set value range, the controller controls the discharge valve (1-6) to remain closed or close the opened discharge valve and stop discharging the material.

2. The continuous crystallization separation effect detection and feeding method as described in claim 1, characterized in that: In step S4, the controller (1-2) calculates the solid-liquid separation effect by subtracting the clear liquid flow rate fed back by the flow meter (1-4) from the set flow rate of the peristaltic pump (1-1), and the difference is used as the quantitative value of the solid-liquid separation effect.

3. The continuous crystallization separation effect detection and feeding method as described in claim 2, characterized in that: When the difference is greater than the upper limit of the set value range, it is determined that the solid content of the sampled material is too low or the separation flow rate is too slow; when the difference is less than the lower limit of the set value range, it is determined that the solid content of the sampled material is too high or the separation flow rate is too fast.

4. The continuous crystallization separation effect detection and feeding method as described in claim 1, characterized in that: The thickener (1-3) is a cyclone separator with the same length-to-diameter ratio as the thickeners already configured on the production line, and its size is reduced by the same proportion.

5. The continuous crystallization separation effect detection and feeding method as described in claim 1, characterized in that: The material discharge area is divided into multiple areas. Each material discharge area is connected to the peristaltic pump (1-1) through an independent sampling control valve (1-5). The controller (1-2) selectively opens the sampling control valves (1-5) of different areas to sample and analyze the materials in multiple material discharge areas and obtain multi-area distribution data.

6. The continuous crystallization separation effect detection and feeding method as described in claim 1, characterized in that: While controlling the opening or closing of the discharge valve (1-6), the controller (1-2) also controls the switching and speed adjustment of the production line discharge pump based on the calculation results of the solid-liquid separation effect.

7. The continuous crystallization separation effect detection and feeding method as described in claim 1, characterized in that: The peristaltic pump (1-1) is a peristaltic pump with flow regulation function. Its flow rate setting value is steplessly adjusted according to the normal flow rate range of the discharge pump to simulate the separation effect under different flow rates.

8. A continuous crystallization separation effect testing and feeding facility, based on the continuous crystallization separation effect testing and feeding method according to any one of claims 1 to 7, characterized in that: include, A peristaltic pump (1-1) is used to extract material samples from the discharge area of ​​the evaporation crystallization equipment and precisely control the flow rate. Thickener (1-3) is connected to the outlet of peristaltic pump (1-1) and is used to perform solid-liquid separation on the material sample conveyed by peristaltic pump (1-1); A flow meter (1-4) is connected to the clear liquid outlet of the thickener (1-3) and is used to measure the flow rate of the clear liquid separated by the thickener (1-3). The controller (1-2) is connected to the flow meter (1-4), the peristaltic pump (1-1), and the discharge valve (1-6) respectively. It is used to calculate the solid-liquid separation effect based on the flow rate of the peristaltic pump (1-1) and the clear liquid flow rate fed back by the flow meter (1-4), and to control the opening or closing of the discharge valve (1-6) according to the calculation result. The discharge valve (1-6) is installed on the discharge pipeline of the evaporation crystallization equipment and is connected to the controller (1-2) for performing the discharge operation according to the control signal of the controller (1-2).

9. The continuous crystallization separation effect detection and discharge facility as described in claim 8, characterized in that: Also includes: At least one control valve (1-5) is installed on the pipeline between different discharge areas of the evaporation crystallization equipment and the peristaltic pump (1-1), and is signal-connected to the controller (1-2) for selectively opening or closing according to the control signal of the controller (1-2) to sample and analyze the material in different areas.

10. The continuous crystallization separation effect detection and discharge facility as described in claim 8, characterized in that: The concentrated solids outlet and the clear liquid outlet of the thickener (1-3) are returned to the evaporation and crystallization equipment through pipelines.

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