Online liquid concentration detection device and method
Through the dual laser beam online liquid concentration detection device, the different wavelength characteristics of the first laser and the second laser are utilized, combined with the spectrometer and photovoltaic converter, the accuracy of liquid concentration detection in modern factories is solved, and efficient real-time concentration feedback and production optimization are achieved.
Patent Information
- Application Number
- CN202510234302.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-28
- Publication Date
- 2025-07-01
AI Technical Summary
The prior art cannot meet the accuracy of modern factories for online liquid concentration detection, especially in the production process of alcoholic beverages and chemical raw materials. Traditional methods cannot feedback changes in ethanol concentration in real time, resulting in high defect rate and low production efficiency.
Using the dual laser beam detection method, the center wavelength of the first laser is located in the absorption peak of the liquid solute to be measured, and the center wavelength of the second laser is located outside the absorption peak of the solvent. The beam is divided by the spectrometer and converted into an electrical signal from the photoelectric tube. The data processing is carried out in combination with the information processing module to shield the dirt influence of the light-transmitting container and realize accurate concentration measurement.
It realizes accurate and reliable real-time detection of liquid concentration, reduces defective rates, optimizes production processes, improves production efficiency and reduces energy consumption.
Smart Images
Figure CN120232840A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of liquid concentration detection, and particularly relates to an online liquid concentration detection method. Background Art
[0002] With the advancement of modernization and the popularization of unmanned workshops, the demand for online detection sensors is increasing. Traditional chemical analysis of concentration no longer meets the needs of modern factories.
[0003] In the production processes of alcoholic beverages, chemical raw materials (such as ethanol as a solvent or reactant), biofuels, etc., accurately controlling the ethanol concentration is the key to ensuring product quality and consistency. Online detection can provide real-time feedback on the ethanol concentration during the production process, timely adjust process parameters, reduce the defective rate and waste. By monitoring the ethanol concentration in real time, enterprises can optimize the production process, improve production efficiency, and reduce energy consumption and costs. For example, during the fermentation process, changes in the ethanol concentration can indicate the progress and efficiency of fermentation, so as to adjust the fermentation conditions to maximize the yield.
[0004] Therefore, designing an online liquid concentration detection method with high accuracy is an urgent problem to be solved at present. Summary of the Invention
[0005] The purpose of the present invention is to overcome the disadvantages and deficiencies of the existing technology, and provide an online liquid concentration detection device and method.
[0006] The technical solutions adopted by the present invention are as follows:
[0007] The first aspect of the present invention provides an online liquid concentration detection device, which includes a laser emission module, a measurement module, and an information processing module. The liquid to be measured is located in a light-transmitting container.
[0008] The laser emission module is used to emit laser beams, and includes a first laser and a second laser. The central wavelength λ1 of the first laser is within the absorption peak of the solute of the liquid to be measured, and the central wavelength λ2 of the second laser beam is outside the absorption peaks of the solute and solvent of the liquid to be measured.
[0009] The laser beams emitted by the first laser and the second laser respectively enter the measurement module alone under the switching of the optical switch.
[0010] The measurement module includes:
[0011] A spectroscope, which is used to divide the first laser beam into a first standard laser beam and a first test laser beam, and divide the second laser beam into a second standard laser beam and a second test laser beam.
[0012] A first detection phototube, which receives the first standard laser beam / second standard laser beam, converts it into an electrical signal, and then transmits it to the information processing module.
[0013] A second detection phototube that receives the first test laser beam / second test laser beam that sequentially passes through the front wall of the light-transmitting container, the liquid to be measured, and the rear wall of the light-transmitting container, converts it into an electrical signal, and then transmits it to the information processing module;
[0014] The information processing module processes the electrical signals of each laser beam sent by the first detection phototube and the second detection phototube to obtain the concentration of the liquid to be measured.
[0015] Preferably, the measurement module further includes a polarizer disposed on the outgoing light path of the laser beam emitted by the laser emission module for restricting the passage of light with a non-set polarization angle in the laser beam;
[0016] Preferably, the measurement module further includes a focusing lens disposed on the transmitted light path of the polarizer for collimating the laser beam transmitted through the polarizer.
[0017] Preferably, the measurement module further includes a first constant temperature component for providing a constant temperature for the first detection phototube.
[0018] Preferably, the measurement module further includes a second constant temperature component for providing a constant temperature for the second detection phototube.
[0019] Preferably, the measurement module further includes a heat insulation component for blocking the temperature conduction between the constant temperature component and the light-transmitting container.
[0020] Preferably, the measurement module further includes a temperature sensor for detecting the temperature of the liquid to be measured.
[0021] Preferably, the optical switch and the measurement module are transmitted through an optical fiber.
[0022] The second aspect of the present invention provides an on-line liquid concentration detection method, which is based on an on-line liquid concentration detection device as described above and includes the following steps:
[0023] S1. Determine the fitting curve between the concentration of the liquid to be measured and the value of the laser energy absorbed by the liquid to be measured:
[0024] S1.1. The first laser emits a laser beam L with a wavelength of λ1 to the measurement module. The laser beam L is divided into a first standard laser beam L a and a first test laser beam L b by a beam splitter. The first standard laser beam L a enters the first detection phototube, and the detected power value is denoted as W a . The first test laser beam L b sequentially passes through the front wall of the light-transmitting container, the liquid to be measured with a known concentration, and the rear wall of the light-transmitting container and enters the second detection phototube. The detected power value is denoted as W b , Wb The ratio with W a is the value I of the laser energy absorbed by the liquid to be measured at this concentration,
[0025] S1.2. Use the steps in S1.1 to measure I at multiple calibration concentrations, and determine the fitting curve between I and the concentration of the liquid to be measured;
[0026] S2. Obtain the current concentration of the liquid to be measured using the fitting curve:
[0027] S2.1. The first laser emits a laser beam L1 with a wavelength of λ1 to the measurement module. The laser beam L1 is split by a beam splitter into a first standard laser beam L 1a and a first test laser beam L 1b . The first standard laser beam L 1a enters the first detection phototube, and the detected power value is denoted as W 1a . The first test laser beam L 1b successively passes through the front wall of the transparent container, the liquid to be measured, and the rear wall of the transparent container and enters the second detection phototube. The detected power value is denoted as W 1b . The ratio of W 1b to W 1a is denoted as I1;
[0028] S2.2. The second laser emits a laser beam L2 with a wavelength of λ2 to the measurement module. The laser beam L2 is split by the beam splitter 203 into a first standard laser beam L 2a and a first test laser beam L 2b . The first standard laser beam L 2a enters the first detection phototube, and the detected power value is denoted as W 2a . The first test laser beam L 2b successively passes through the front wall of the transparent container, the liquid to be measured, and the rear wall of the transparent container and enters the second detection phototube. The detected power value is denoted as W 2b . The ratio of W 2b to W 2a is denoted as I2;
[0029] S2.3. The ratio of I1 to I2 is the value of the laser energy absorbed by the liquid to be measured after calibration. The current concentration value of the liquid to be measured is obtained through the value of the laser energy absorbed by the liquid to be measured after calibration and the fitting curve.
[0030] The beneficial effects of the present invention are as follows: By providing two laser beams with a central wavelength within the absorption peak of the solute of the liquid to be measured and a central wavelength outside the absorption peaks of the solute and solvent of the liquid to be measured, the two laser beams respectively enter the measurement module. The laser beams are split by a beam splitter and the values are measured by phototubes to obtain the laser power values of the laser beam passing through the sample to be measured and the laser beam not passing through the sample to be measured, which can effectively shield the influence of the dirt on the transparent container on the power measurement value and obtain a more accurate and reliable real-time concentration result. Brief Description of the Drawings
[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, obtaining other drawings based on these drawings still belongs to the scope of the present invention.
[0032] Figure 1 It is a schematic structural diagram of Embodiment 1 of the present invention;
[0033] In the figure, 101 is the first laser; 102 is the second laser; 111 is an optical switch; 201 is a polarizer; 202 is a focusing lens; 203 is a beam splitter; 301 is the first detection photoelectric tube; 302 is the second detection photoelectric tube; 401 is the first constant temperature component; 402 is the second constant temperature component; 404 is a temperature sensor; 501 is a transmission optical fiber; 4031 is the first heat insulation plate; 4032 is the second heat insulation plate. Detailed Description of the Embodiments
[0034] In order to make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the drawings.
[0035] Example 1
[0036] As Figure 1 shown, this embodiment provides an on-line liquid concentration detection device, which includes a laser emission module, a measurement module, and an information processing module. The liquid to be measured is located in a light-transmitting container.
[0037] The laser emission module is used to emit laser beams, and includes a first laser 101 and a second laser 102. The central wavelength λ1 of the first laser 101 is within the absorption peak of the solute of the liquid to be measured, and the central wavelength λ2 of the second laser beam is outside the absorption peaks of the solute and solvent of the liquid to be measured.
[0038] The laser beams emitted by the first laser 101 and the second laser 102 respectively enter the measurement module independently under the switching of the optical switch 111. The optical switch 111 is connected to the measurement module through the transmission optical fiber 501 and transmits.
[0039] The measurement module includes:
[0040] The polarizer 201 is disposed on the outgoing light path of the laser beam emitted by the laser emission module and is used to limit the passage of light with non-set polarization angles in the laser beam. Since the splitting ratio of the laser with different polarizations by the beam splitter has a slight deviation, it is easy to reduce the measurement accuracy of the system. Therefore, a polarizer is added to eliminate the reduction in accuracy caused by the change in the polarization direction of the light source. In this application, a polarizing film is specifically used. When integrating the measurement module into an optical element, standard optical fiber connectors such as FC heads can be used to cooperate with the fiber optic socket for fixation.
[0041] The focusing lens 202 is disposed on the transmission light path of the polarizer 201 and is used to collimate the laser beam transmitted through the polarizer 201. The collimated beam is thinner, reducing the excessive absorption of laser energy by the liquid and improving the reception of laser energy by the phototube.
[0042] The beam splitting component 203 is used to divide the first laser beam into a first standard laser beam and a first test laser beam, and divide the second laser beam into a second standard laser beam and a second test laser beam. The beam splitting component specifically uses a beam splitter, and the beam splitting ratio of the beam splitter is specifically set to 3:7. 70% of the light enters the first detection phototube 301 after passing through the liquid, and 30% enters the second detection phototube 302.
[0043] The first detection phototube 301 receives the first standard laser beam / second standard laser beam, converts it into an electrical signal, and then transmits it to the information processing module.
[0044] The second detection phototube 302 receives the first test laser beam / second test laser beam that sequentially passes through the front wall of the light-transmitting container, the liquid to be measured, and the rear wall of the light-transmitting container, converts it into an electrical signal, and then transmits it to the information processing module; wherein, the front and rear walls of the light-transmitting container are preferably set as parallel planes to reduce the interference effect of the curved surface and other forms on the laser path and improve the accuracy of detection; the information processing module processes the electrical signals of each laser beam sent by the first detection phototube 301 and the second detection phototube 302 to obtain the concentration of the liquid to be measured, and the information processing module is specifically a computer.
[0045] The first constant temperature component 401 provides a constant temperature for the first detection phototube 301. The first constant temperature component 401 can specifically use a constant temperature sheet. When integrating the measurement module into an optical element, the constant temperature sheet and the socket of the first detection phototube 301 are set to be closely attached to provide a constant temperature for the first detection phototube 301 and its socket, so that the first detection phototube 301 has a constant photoelectric conversion factor.
[0046] The second constant temperature component 402 provides a constant temperature for the second detection phototube 302. The second constant temperature component 402 can specifically use a constant temperature sheet. When integrating the measurement module into an optical element, the constant temperature sheet and the socket of the second detection phototube 302 are set to be closely attached to provide a constant temperature for the second detection phototube 302 and its socket, so that the second detection phototube 302 has a constant photoelectric conversion factor.
[0047] The heat insulation component 403 is used to block the temperature conduction between the constant temperature component and the light-transmitting container. The heat insulation component 403 can specifically adopt a heat insulation board, including a first heat insulation board 4031 and a second heat insulation board 4031 respectively arranged on the front wall and the rear wall of the light-transmitting container, so as to better stabilize the temperatures of the first detection photoelectric tube 301 and the second detection photoelectric tube 302.
[0048] The temperature sensor 404 is used to detect the temperature of the liquid to be measured. When the measurement module is integrated into an optical element, the temperature sensor 404 is embedded in the liquid pipeline and is located between the front and rear walls of the light-transmitting container, and the end face is in contact with the liquid.
[0049] Example 2
[0050] This embodiment provides an online liquid concentration detection method based on the online liquid concentration detection device of Embodiment 1, and includes the following steps:
[0051] S1. Determine the fitting curve between the concentration of the liquid to be measured and the value of the laser energy absorbed by the liquid to be measured:
[0052] S1.1. The first laser 101 emits a laser beam L with a wavelength of λ1 to the measurement module. The laser beam L is divided into a first standard laser beam L a and a first test laser beam L b by the beam splitter 203. The first standard laser beam L a enters the first detection photoelectric tube 301, and the detected power value is denoted as W a . The first test laser beam L b successively passes through the front wall of the light-transmitting container, the liquid to be measured with a known concentration, and the rear wall of the light-transmitting container and enters the second detection photoelectric tube 302. The detected power value is denoted as W b . The ratio of W b to W a is the value I of the laser energy absorbed by the liquid to be measured at this concentration.
[0053] S1.2. Use the steps in S1.1 to measure multiple groups of I values at calibration concentrations, and determine the fitting curve between I and the concentration of the liquid to be measured. The fitting curve can be expressed by the following formula:
[0054] x = (k1*(I) 4 ―k2(I) 3 +k3(I) 2 +k4*I + k5)*100,
[0055] where x is the concentration of the liquid to be measured, and k1, k2, k3, k4, and k5 are scalars of the fitting curve;
[0056] S2. Obtain the current concentration of the liquid to be measured by using the fitting curve:
[0057] S2.1. The first laser 101 emits a laser beam L1 with a wavelength of λ1 to the measurement module. The laser beam L1 is divided by the beam splitter 203 into a first standard laser beam L 1a and a first test laser beam L 1b . The first standard laser beam L 1a enters the first detection photoelectric tube 301, and the detected power value is denoted as W 1a . The first test laser beam L 1b successively passes through the front wall of the light-transmitting container, the liquid to be measured, and the back wall of the light-transmitting container and enters the second detection photoelectric tube 302. The detected power value is denoted as W 1b . The ratio of W 1b to W 1a is denoted as I1;
[0058] S2.2. The second laser 102 emits a laser beam L2 with a wavelength of λ2 to the measurement module. The laser beam L2 is divided by the beam splitter 203 into a first standard laser beam L 2a and a first test laser beam L 2b . The first standard laser beam L 2a enters the first detection photoelectric tube 301, and the detected power value is denoted as W 2a . The first test laser beam L 2b successively passes through the front wall of the light-transmitting container, the liquid to be measured, and the back wall of the light-transmitting container and enters the second detection photoelectric tube 302. The detected power value is denoted as W 2b . The ratio of W 2b to W 2a is denoted as I2;
[0059] S2.3. The ratio of I1 to I2 is the value of the laser energy absorbed by the liquid to be measured after calibration, denoted as I3. Substitute the value of the laser energy absorbed by the liquid to be measured after calibration I3 into the fitting curve formula (substitute I in the formula) to obtain the current concentration value x of the liquid to be measured.
[0060] Example 3
[0061] In this embodiment, the online liquid concentration detection method of Embodiment 2 is specifically applied to the detection of alcohol concentration, where λ1 = 1396 nm and λ2 = 1310 nm.
[0062] The above-disclosed are only the preferred embodiments of the present invention. Of course, the scope of the rights of the present invention cannot be limited thereby. Therefore, equivalent changes made according to the claims of the present invention still fall within the scope covered by the present invention.
Claims
1. An online liquid concentration detection device, characterized in that: It includes a laser emission module, a measurement module, and an information processing module. The liquid to be measured is located in a light-transmitting container. The laser emission module is used for emitting a laser beam and comprises a first laser (101) and a second laser (102), wherein the central wavelength λ1 of the first laser (101) is within the absorption peak of the liquid solute to be measured, and the central wavelength λ2 of the second laser beam is outside the absorption peaks of the liquid solute and solvent to be measured, The laser beams emitted by the first laser (101) and the second laser (102) enter the measurement module independently under the switching of the optical switch (111); The measuring module comprises: The beam splitter (203) is used to split the first laser beam into a first standard laser beam and a first test laser beam, and split the second laser beam into a second standard laser beam and a second test laser beam. The first detection photoelectric tube (301) receives the first standard laser beam / the second standard laser beam and converts it into an electrical signal and transmits it to the information processing module. The second detection photoelectric tube (302) receives the first test laser beam / the second test laser beam which passes through the front wall of the light-transmitting container, the liquid to be tested and the rear wall of the light-transmitting container in sequence, converts the electrical signal into an electrical signal and transmits it to the information processing module; The information processing module performs data processing on the laser beam electrical signals sent by the first detection photoelectric tube (301) and the second detection photoelectric tube (302) to obtain the concentration of the liquid to be measured.
2. An online liquid concentration detection device according to claim 1, characterized in that: The measurement module also includes a polarizer (201) which is arranged on the outgoing light path of the laser beam emitted by the laser emission module and is used to limit the passage of light with a non-set polarization angle in the laser beam.
3. An online liquid concentration detection device according to claim 2, characterized in that: The measurement module further comprises a focusing mirror (202) which is arranged on the transmission light path of the polarizer (201) and is used for collimating the laser beam transmitted through the polarizer (201).
4. The on-line liquid concentration detection device according to claim 1, characterized in that: The measurement module further comprises a first constant temperature component (401) for providing a constant temperature for the first detection photoelectric tube (301).
5. An online liquid concentration detection device according to claim 4, characterized in that: The measuring module further comprises a second constant temperature component (402) for providing a constant temperature for the second detection photoelectric tube (302).
6. An online liquid concentration detection device according to claim 5, characterized in that: The measuring module also includes a heat insulation component for blocking temperature conduction between the constant temperature component and the light-transmitting container.
7. The on-line liquid concentration detection device according to claim 1, characterized in that: The measurement module also includes a temperature sensor (404) for detecting the temperature of the liquid to be measured.
8. The on-line liquid concentration detection device according to claim 1, characterized in that: The optical switch (111) and the measuring module are transmitted via a transmission optical fiber (501).
9. An online liquid concentration detection method, characterized in that: It is based on an online liquid concentration detection device according to any one of claims 1 to 8, and comprises the following steps: S1. Determine the fitting curve between the concentration of the liquid to be tested and the laser energy value absorbed by the liquid to be tested: S1.
1. The first laser (101) emits a laser beam L with a wavelength of λ1 to the measurement module. The laser beam L is divided into a first standard laser beam L by a beam splitter (203) a and the first test laser beam L b , the first standard laser beam L a Entering the first detection photoelectric tube (301), the power value detected is recorded as W a , the first test laser beam L b The light passes through the front wall of the light-transmitting container, the liquid to be tested with a known concentration, and the rear wall of the light-transmitting container and enters the second detection photoelectric tube (302). The power value detected is recorded as W b , W b With W a The ratio is the laser energy value I absorbed by the liquid under test at this concentration. S1.
2. Determine I at multiple calibration concentrations using step S1.1 to determine a fitting curve between I and the concentration of the liquid to be tested; S2. Use the fitting curve to obtain the current concentration of the liquid to be tested: S2.
1. The first laser (101) emits a laser beam L1 with a wavelength of λ1 to the measurement module. The laser beam L1 is divided into a first standard laser beam L1 by a beam splitter (203). 1a and the first test laser beam L 1b , the first standard laser beam L 1a Entering the first detection photoelectric tube (301), the power value detected is recorded as W 1a , the first test laser beam L 1b The light passes through the front wall of the light-transmitting container, the liquid to be tested, and the rear wall of the light-transmitting container and enters the second detection photoelectric tube (302). The power value detected is recorded as W 1b , W 1b With W 1a The ratio is recorded as I1; S2.
2. The second laser (102) emits a laser beam L2 with a wavelength of λ2 to the measurement module. The laser beam L2 is divided into a first standard laser beam L2 by a beam splitter (203). 2a and the first test laser beam L 2b , the first standard laser beam L 2a Entering the first detection photoelectric tube (301), the power value detected is recorded as W 2a , the first test laser beam L 2b The light passes through the front wall of the light-transmitting container, the liquid to be tested, and the rear wall of the light-transmitting container and enters the second detection photoelectric tube (302). The power value detected is recorded as W 2b , W 2b With W 2a The ratio is recorded as I2; S2.
3. The ratio of I1 to I2 is the calibrated laser energy absorption value of the liquid to be tested. The current concentration value of the liquid to be tested is obtained by comparing the calibrated laser energy absorption value of the liquid to be tested with the fitting curve.