Method for representing stability of feed liquid in leaf feeding pipeline based on turbidity change

Abstract

The invention belongs to the technical field of tobacco processing, and relates to a method for representing the stability of feed liquid in a leaf feeding pipeline based on turbidity change, which comprises the following steps: 1, data acquisition and transmission; 2, the control system analyzes and stores feed liquid data; 3, calculating and judging operation parameters of the feed liquid stability grading regulation and control system according to the control system and / or sending sound-light alarm and character prompt; according to the method, the stability of the feed liquid in the leaf feeding pipeline is accurately monitored and automatically regulated and controlled by collecting the turbidity data of the two points in real time and combining a three-stage quantitative characterization system of spatial difference, time fluctuation and a comprehensive stability index.

Description

Technical Field

[0001] This invention belongs to the field of tobacco processing technology, specifically relating to a method for characterizing the stability of the feed liquid in a leaf feeding pipeline based on changes in turbidity. Background Technology

[0002] The leaf feeding pipeline in a cigarette manufacturing plant is a system used to transport the slurry (mainly composed of sugars, tobacco extract, and flavorings) from the slurry pool to the feeding machine drum and then evenly spray it onto the tobacco leaves. Its core function is to ensure the precise and stable application of the slurry, directly affecting the sensory quality and processing efficiency of the cigarettes. As a critical process in the cigarette manufacturing plant, the leaf feeding pipeline, through precise structural design and automated control, ensures the uniformity, stability, and efficiency of slurry addition, directly impacting the sensory quality of the cigarette products and controlling production energy consumption.

[0003] Currently, the stability monitoring of the feed liquid in the tobacco processing workshop of cigarette factories mainly relies on two methods. The first is manual sampling and testing at fixed intervals. Staff members take samples of the feed liquid from specific points in the pipeline at fixed times, and analyze indicators such as the concentration and uniformity of the composition of the feed liquid using laboratory instruments to determine its stability. The second is to use a single flow or pressure sensor to monitor only the flow rate or pressure changes of the feed liquid in the pipeline, and indirectly infer whether there are problems such as flow interruption or blockage.

[0004] However, the existing feed pipeline has significant shortcomings in the detection of feed liquid stability: manual sampling and testing is delayed, and it takes a certain amount of time from sampling to obtaining the test results. If the stability of the feed liquid is abnormal during this period, it is difficult to detect and adjust in time, which can easily lead to unqualified batch feeding of blades; a single flow or pressure sensor cannot directly reflect the uniformity of the feed liquid itself. For example, when the feed liquid is layered or the concentration fluctuates, the flow rate and pressure may not change significantly, and it is impossible to accurately judge the stability of the feed liquid.

[0005] Therefore, there is a need for a material stability testing device or method that can perform real-time monitoring, accurate detection, reliable detection, and automatic detection to solve the above-mentioned technical problems. Summary of the Invention

[0006] This invention provides the following technical solution: a method for characterizing the stability of feed liquid in a blade feeding pipeline based on turbidity changes, comprising the following steps: Step 1: Data Acquisition and Transmission. Collect liquid data from different locations in the feeding pipeline and transmit it to the control system in real time. The liquid data includes: real-time turbidity value and data acquisition timestamp. Step 2: The control system analyzes and stores the liquid data. The control system adopts a three-level characterization system of "spatial difference characterization + temporal fluctuation characterization + comprehensive stability index". The stability of the liquid is determined by quantitative calculation. Spatial difference characterization is used to reflect the uniformity of the liquid during the transfer process, temporal fluctuation characterization is used to reflect the instantaneous stability of the liquid at the same location, and comprehensive stability index is used to reflect the overall stability of the liquid. Step 3: Adjust the operating parameters of the grading control system for the stability of the feed liquid according to the calculation and determination of the control system, and / or send audible and visual alarms and text prompts.

[0007] Preferably, in step 1, the data acquisition device for the feeding pipeline includes: a first online turbidity detector, a second online turbidity detector, a feeding pump, a dual-element atomizing nozzle, a material tank, a feeding pipeline, a material tank stirring motor, and a control system.

[0008] The first and second online turbidity detectors are located at different positions on the feeding pipeline. The material tank is connected to the inlet of the feeding pipeline, and the outlet of the feeding pipeline is connected to the dual-element atomizing nozzle. The stirring end of the material tank stirring motor extends into the material tank. The feeding pump is connected in series on the feeding pipeline. The first and second online turbidity detectors, the material tank stirring motor, and the feeding pump are all electrically connected to the control system.

[0009] More preferably, in step 1, the different data acquisition locations of the feeding pipeline include: the material tank outlet and in front of the dual atomizing nozzle.

[0010] More preferably, in step 2, spatial variability is characterized as follows:

[0011] In the formula, The value represents the average turbidity of the first online turbidity analyzer within the analysis period T. ; The average turbidity value of the second online turbidity analyzer within the analysis period T. NTU1(t) and NTU2(t) are the real-time turbidity values ​​of the first online turbidity detector and the second online turbidity detector at time t, respectively.

[0012] More preferably, in step 2, the time fluctuation is characterized as follows:

[0013]

[0014] In the formula, The standard deviation of turbidity in the first online turbidity analyzer during the analysis period T; is the standard deviation of the turbidity of the second on-line turbidity detector within the analysis period T.

[0015] Preferably, in step 2, the comprehensive stability index is characterized as:

[0016] In the formula, w1 and w2 are weighting coefficients, is the maximum standard deviation of the allowable time fluctuation of the feed liquid, and NTU0 is the process target turbidity value of the feed liquid.

[0017] Preferably, in step 3, the specific rules for the control system to calculate and determine include: When SI ≤ 0.1: It is determined that the overall feed liquid is stable, and the system maintains the current operating parameters; When 0.1 < SI ≤ 0.2: It is determined that the feed liquid is slightly unstable, and the system increases the operating frequency of the tank stirring motor by 10% - 15% and maintains the stirring interval unchanged; When SI > 0.2: It is determined that the feed liquid is severely unstable, and the system increases the stirring motor frequency by 15% - 20%, simultaneously shortens the stirring interval, and sends an audible and visual alarm and a text prompt to the workshop operation terminal to remind the staff to check whether there are any abnormal problems.

[0018] Preferably, the abnormal problems include: pipeline blockage, and the feeding pump cannot work properly; the text prompt includes: displaying "The stability of the feed liquid exceeds the standard, enhanced stirring has been started, please pay attention to the pipeline operation status".

[0019] The beneficial effects of the present invention are: 1. Through the high-frequency acquisition of the on-line turbidity detector at 1 time / second and the real-time calculation of the control system in the present invention, the total delay from data acquisition to the sending of the control command ≤ 2 seconds, completely eliminating the lag of manual sampling, avoiding unqualified batch blade feeding, and solving the lag problem of the existing feed liquid stability detection.

[0020] 2. Based on the "space + time" two-dimensional characterization and the comprehensive stability index, compared with the indirect parameter monitoring of the prior art, the present invention directly quantifies the uniformity and volatility of the feed liquid itself; the hierarchical control logic is designed based on the quantitative index, avoiding over-stirring or insufficient control, ensuring both the uniformity of the feed liquid and reducing the motor energy consumption, realizing the precise and automatic control of the feed liquid stability detection.

[0021] 3. The present invention does not require manual sampling, detection, and manual control. The system automatically completes the entire process of "monitoring - calculation - determination - control - warning", reducing the manual operation link, avoiding manual errors, and improving the reliability of the system operation. Therefore, the present invention reduces the labor cost and labor intensity of the feed liquid stability detection.

[0022] 4. All judgments in this invention are based on quantitative formulas, and the data is storable and traceable, facilitating subsequent process optimization (e.g., adjusting the initial parameters of the stirring motor or NTU0 by analyzing historical SI value changes). (equal thresholds), therefore the material stability detection and characterization system of the present invention is scientifically traceable. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the apparatus setup for a method of characterizing the stability of liquid feed in a blade feeding pipeline based on turbidity changes, according to the present invention. Figure 2 This is a schematic diagram of the method steps of the present invention.

[0024] In the diagram, 1. First online turbidity detector; 2. Second online turbidity detector; 3. Feed pump; 4. Dual-element atomizing nozzle; 5. Material tank; 6. Feeding pipeline; 7. Material tank stirring motor; 8. Control system. Detailed Implementation

[0025] The related technologies of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0026] like Figures 1-2 As shown in the figure, this embodiment of a method for characterizing the stability of the feed liquid in the blade feeding pipeline based on turbidity changes involves installing two online turbidity detectors at different locations in the feeding pipeline 6, combined with the control system 8, to achieve real-time monitoring of the stability of the feed liquid quality and precise control of the tank stirring motor 7. The specific structure and process are as follows: Equipment installation and layout: In the feeding pipeline 6, a first online turbidity detector 1 is installed at the outlet pipeline of the material tank 5 (0.5-1.0m away from the outlet flange of the material tank 5 to avoid turbulence interference at the outlet) to detect the turbidity of the initial output state of the liquid. A second online turbidity detector 2 is installed at the feeding pipeline 6 0.3-0.5m before the dual-element atomizing nozzle 4 to detect the turbidity of the liquid at the final state before it is applied to the blades. The feeding pump 3 is responsible for transporting the liquid from the material tank 5 to the feeding pipeline 6, and the dual-element atomizing nozzle 4 realizes the atomization application of the liquid. The material tank stirring motor 7 is installed at the center of the top of the material tank 5 to stir the liquid. The control system 8 is connected to the two turbidity detectors and the material tank stirring motor 7 to complete data acquisition, analysis and judgment, and control command transmission.

[0027] Data acquisition and transmission Both the first and second online turbidity detectors use the scattering light method, which conforms to the ISO 7027 international standard for turbidity measurement, with a sampling frequency of 1 time / second. The collected data includes real-time turbidity values ​​and data acquisition timestamps. The collected data is transmitted in real time to the control system 8 via a 4-20mA analog signal. The control system 8 has a built-in data cache module that stores the most recent 5 minutes of continuous detection data for fluctuation analysis.

[0028] Methods for characterizing the stability of liquid feed This implementation method adopts a three-level characterization system of "spatial difference characterization + time fluctuation characterization + comprehensive stability index" to achieve objective and accurate determination of the stability of the feed liquid through quantitative calculation.

[0029] Basic parameter definitions: Definition: NTU1(t) is the real-time turbidity value of the first online turbidity detector 1 at time t (t∈[t0, t0+T], where T is the analysis period, taken as 60 seconds, i.e., continuous data within 1 minute). NTU2(t) is the real-time turbidity value of the second online turbidity detector 2 at time t; NTU0 is the target turbidity value of the feed liquid in the process. This represents the maximum allowable standard deviation of the time fluctuation in the feed solution. w1 and w2 are weighting coefficients (w1+w2=1, where w1=0.6 and w2=0.4, set based on the process characteristic that spatial uniformity has a greater impact on the feeding quality).

[0030] Spatial variability characterization: uniformity of the reaction liquid during transport.

[0031] During the transfer of the liquid from the feed tank outlet to the atomizing nozzle, if the mixing is uniform, the turbidity difference between the two points should be controlled within a reasonable range. The spatial difference is quantified using the "absolute difference in turbidity," and the calculation formula is as follows:

[0032] in: , is the average turbidity value of the first online turbidity detector 1 within the analysis period T (n=60, corresponding to a sampling frequency of 1 time / second). , is the average turbidity value of the second online turbidity detector 2 within the analysis period T; Physical meaning: The larger the ΔNTU, the worse the uniformity of concentration and composition of the liquid during the transmission process, and the more significant the spatial differences.

[0033] Time fluctuation characterization: reflects the instantaneous stability of the liquid at the same location.

[0034] Excessive instantaneous turbidity fluctuations at a single location may still lead to problems such as liquid stratification and local concentration mutations in the feed liquid, even if the spatial difference is small. The "standard deviation" is used to quantify the time fluctuations, and the calculation formula is as follows:

[0035]

[0036] Where: is the standard deviation of the turbidity of the first on-line turbidity detector 1 within the analysis period T; is the standard deviation of the turbidity of the second on-line turbidity detector 2 within the analysis period T; Physical meaning: The larger the standard deviation, the more剧烈 the instantaneous turbidity fluctuations of the feed liquid at that location, and the worse the stability of the feed liquid (for example when it indicates that there are frequent fluctuations in the feed liquid at the outlet of the feed tank).

[0037] Characterization of the comprehensive stability index: Comprehensively reflects the overall stability of the feed liquid.

[0038] Combining spatial differences and time fluctuations, a comprehensive stability index SI (Stability Index) is constructed to achieve a comprehensive quantitative determination of the stability of the feed liquid. The calculation formula is as follows:

[0039] Where: The first term is the contribution value of the spatial difference (normalized to eliminate the influence of the target turbidity difference); the second term is the contribution value of the time fluctuation (normalized to unify the fluctuation evaluation criteria); Physical meaning: , the smaller the SI value, the better the overall stability of the feed liquid; when the SI value exceeds the set threshold, it is determined that the feed liquid is unstable and the control measures are started.

[0040] Determination of stability level and automatic control: Based on the optimized logic of the comprehensive index.

[0041] The control system 8 calculates ΔNTU, , and the comprehensive stability index SI in real time, and starts hierarchical control according to the SI value and each sub-index. The specific rules are as follows: When SI ≤ 0.1 (corresponding to ΔNTU ≤ 10 NTU, and , ): It is determined that the overall feed liquid is stable, and the control system maintains the current operating parameters (frequency, interval) of the stirring motor 7 of the feed tank unchanged; When 0.1 < SI ≤ 0.2 (corresponding to 10 NTU < ΔNTU ≤ 20 NTU, and If the liquid material is found to be slightly unstable, the system will increase the operating frequency of the mixing motor 7 in the tank by 10% to 15% while maintaining the mixing interval unchanged. When SI > 0.2 (corresponding to ΔNTU > 20NTU, or If the system determines that the liquid material is unstable, it will increase the frequency of the stirring motor by 15% to 20% and shorten the stirring interval (e.g., from 5 minutes / time to 2 minutes / time). It will also send an audible and visual alarm and a text prompt (displaying "Liquid material stability exceeds the standard, enhanced stirring has been started, please pay attention to the pipeline operation status") to the workshop operation terminal, reminding staff to check for problems such as pipeline blockage or abnormal feeding pump.

[0042] In summary, this invention achieves precise monitoring and automatic control of the stability of the feed liquid in the leaf-feeding pipeline by real-time acquisition of dual-point turbidity data combined with a three-level quantitative characterization system of spatial differences, temporal fluctuations, and a comprehensive stability index. This method completely solves the technical problems of strong lag in traditional manual sampling and inaccurate monitoring by single sensors. Its core advantages are: first, high-frequency data acquisition of 1 time / second and a control response speed of ≤2 seconds ensure immediate detection and handling of feed liquid anomalies; second, the graded control logic based on quantitative formulas avoids energy waste caused by excessive stirring and prevents quality fluctuations caused by insufficient control; third, the fully automated operation reduces manual intervention, and the data storage and traceability characteristics provide a scientific basis for process optimization. This technical solution has been verified through actual production and can significantly improve the feeding uniformity and production efficiency in cigarette manufacturing workshops, possessing high value for widespread application.

[0043] It should be emphasized that the above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any way. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention shall still fall within the scope of the technical solution of the present invention.

Claims

1. A method for characterizing the stability of a feed liquid in a blade feed line based on a change in turbidity, characterized by, It comprises the following steps: Step 1, data acquisition and transmission, collecting the data of the material liquid in the feeding pipeline at different positions and transmitting it to the control system in real time; the data of the material liquid includes: real-time turbidity value, data acquisition time stamp; Step 2, the control system analyzes and stores the data of the material liquid, and the control system adopts a three-level representation system of "spatial difference representation + time fluctuation representation + comprehensive stability index", and realizes the judgment of the stability of the material liquid through quantitative calculation; the spatial difference representation is used to reflect the uniformity of the material liquid in the transmission process, the time fluctuation representation is used to reflect the instantaneous stability of the material liquid at the same position, and the comprehensive stability index is used to reflect the overall stability of the material liquid; Step 3, according to the control system calculation judgment, the running parameters of the material liquid stability grading control system are adjusted and / or the sound and light alarm and the text prompt are sent.

2. A method for characterizing the stability of a feed liquid in a blade feed line based on a change in turbidity according to claim 1, characterized in that, In step 1, the data acquisition device of the feeding pipeline comprises: a first online turbidity detector, a second online turbidity detector, a feeding pump, a double-element atomizing nozzle, a material tank, a feeding pipeline, a material tank stirring motor and a control system; The first online turbidity detector and the second online turbidity detector are arranged at different positions of the feeding pipeline, the inlet of the feeding pipeline is connected with the material tank, the outlet of the feeding pipeline is connected with the double-element atomizing nozzle, and the stirring end of the material tank stirring motor extends into the material tank; the feeding pump is connected in series on the feeding pipeline; The first online turbidity detector, the second online turbidity detector, the material tank stirring motor and the feeding pump are respectively electrically connected to the control system.

3. The method for characterizing the stability of the material liquid in the blade feeding pipe according to claim 2, characterized in that, In step 1, the different data acquisition positions of the feeding pipeline include: the material tank outlet and the front of the double-element atomizing nozzle.

4. The method for characterizing the stability of the material liquid in the blade feeding pipe according to claim 2, characterized in that, In step 2, the spatial difference representation is: In the formula, is the average turbidity value of the first online turbidity detector in the analysis period T, ; is the average turbidity value of the second online turbidity detector in the analysis period T, ; NTU1(t), NTU2(t) are respectively the real-time turbidity values of the first online turbidity detector and the second online turbidity detector at time t.

5. A method for characterizing the stability of a feed liquid in a blade feed line based on a change in turbidity as claimed in claim 4, wherein, In step 2, the time fluctuation representation is: In the formula, is the turbidity standard deviation of the first online turbidity detector in the analysis period T; is the turbidity standard deviation of the second online turbidity detector in the analysis period T.

6. A method for characterizing the stability of a feed liquid in a blade feed line based on a change in turbidity according to claim 5, characterized in that, In step 2, the comprehensive stability index representation is: In the formula, w1, w2 are weight coefficients, is the maximum time fluctuation standard deviation allowed for the feed liquid, and NTU0 is the process target turbidity value of the feed liquid.

7. A method for characterizing the stability of a feed liquid in a blade feed line based on a change in turbidity as claimed in claim 5, wherein, In step 3, the specific rules of the control system calculation judgment include: When SI≤0.1: it is determined that the overall stability of the material liquid is stable, and the system maintains the current running parameters; When 0.1<SI≤0.2: it is determined that the material liquid is slightly unstable, the running frequency of the material tank stirring motor is increased by 10%-15%, and the stirring interval is maintained unchanged; When SI>0.2: it is determined that the material liquid is severely unstable, the stirring motor frequency is increased by 15%-20%, the stirring interval is shortened, and the sound and light alarm and the text prompt are sent to the workshop operation terminal, reminding the staff to check whether there is an abnormal problem.

8. A method for characterizing the stability of a feed liquid in a blade feed line based on a change in turbidity according to claim 7, characterized in that, The abnormal problem includes: pipeline blockage and feeding pump unable to work normally; the text prompt includes: displaying "material liquid stability exceeds the standard, intensive stirring has been started, please pay attention to the running state of the pipeline".

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