Sludge moisture content measuring system based on multiple infrared detection reflection wavebands

Abstract

The invention relates to the technical field of sludge moisture content measurement, and discloses a sludge moisture content measurement system based on multiple infrared detection reflection wavebands, which comprises a bearing plate for bearing sludge, and further comprises an infrared light source for emitting infrared light to irradiate the sludge; the infrared detection array is composed of a plurality of infrared detectors, the infrared detectors are provided with optical filters, and the optical filters are used for limiting the wave band range of infrared light received by the infrared detectors and only allowing the infrared light in the wave band to pass through, so that the infrared detectors output corresponding voltage signals; and the signal processing module is used for receiving and processing the voltage signal output by the infrared detector. According to the sludge moisture content measuring system based on the multiple infrared detection reflection wavebands, rapid and non-contact measurement of the sludge moisture content can be achieved through the infrared spectrum technology, sampling or sludge sample damage is not needed, and meanwhile online real-time monitoring can be achieved.

Description

Technical Field

[0001] The invention relates to the technical field of sludge moisture content measurement, in particular to a sludge moisture content measurement system based on multiple infrared detection reflection bands. Background Art

[0002] In the sewage treatment process, accurate measurement of sludge moisture content is crucial for optimizing the treatment process and improving treatment efficiency. Traditional methods for measuring sludge moisture content mainly include weight method and drying method. Although these methods have certain reliability, they often require sludge samples to be removed from the site for treatment, which is not only complicated and time-consuming, but also difficult to achieve online real-time monitoring.

[0003] As a non-contact measurement technology, infrared spectroscopy has been widely used in the measurement of moisture content in recent years due to its rapid and non-contact characteristics. However, the existing infrared spectroscopy measurement system still has some limitations, especially in the measurement of sludge with complex components. When faced with the interference of multiple components, the single-band infrared detector is difficult to effectively distinguish the moisture signal in the sludge from the absorption signals of other components, which will lead to a decrease in the accuracy and stability of the measurement. Summary of the invention

[0004] 1. Technical issues to be solved

[0005] In view of the shortcomings of the prior art, the present invention provides a sludge moisture content measurement system based on multiple infrared detection reflection bands, which has the advantages of being able to collect signals from characteristic bands and reference bands respectively through multiple infrared detectors, and combining model construction and data processing to accurately measure the sludge moisture content.

[0006] (II) Technical solution

[0007] In order to achieve the above-mentioned purpose of being able to collect signals from characteristic bands and reference bands respectively through multiple infrared detectors, combining model construction and data processing, and accurately measuring the moisture content of sludge, the present invention provides the following technical solutions: A sludge moisture content measurement system based on multiple infrared detection reflection bands, including a carrying plate for carrying sludge, and also including:

[0008] An infrared light source, used for emitting infrared light to irradiate the sludge;

[0009] The infrared detection array is composed of a plurality of infrared detectors, each of which is equipped with a filter. The filter is used to limit the wavelength range of infrared light received by the infrared detector, allowing only infrared light within the wavelength range to pass through, thereby causing the infrared detector to output a corresponding voltage signal;

[0010] A signal processing module, used for receiving and processing the voltage signal output by the infrared detector;

[0011] A model building module, used to build a correlation model between reflected light power and water content;

[0012] The moisture content calculation module calculates the sludge moisture content based on the correlation model.

[0013] As a preferred technical solution of the present invention, the signal processing module includes:

[0014] Signal amplification and filtering unit: used to receive and process the voltage signal output by the infrared detector, amplify the signal and remove noise interference;

[0015] Analog-to-digital conversion unit: used to convert analog signals into high-precision digital signals;

[0016] The data storage unit is used to store the processed voltage signal.

[0017] As a preferred technical solution of the present invention, the infrared detector comprises:

[0018] Characteristic band detector, whose filter is used to receive infrared light affected by sludge moisture absorption and scattering, and output characteristic voltage signal;

[0019] A reference band detector, whose filter is used to receive infrared light that is not affected by sludge moisture absorption and scattering, and output a reference voltage signal;

[0020] The model building module builds a correlation model between the reflected light power and the water content according to the characteristic voltage signal of the characteristic band detector and the reference voltage signal of the reference band detector.

[0021] As a preferred technical solution of the present invention, it also includes:

[0022] A water vapor measurement channel, including a temperature sensor and a humidity sensor, for measuring the temperature and relative humidity in the air and calculating the absolute humidity;

[0023] The absorption interference of water vapor in the air on the infrared light reflection signal is corrected by the absolute humidity value.

[0024] As a preferred technical solution of the present invention, the calibration process includes:

[0025] According to the absolute humidity value of water vapor, the absorption coefficient of water vapor in a specific infrared band is determined. Combined with the reference voltage signal of the reference band detector, the voltage attenuation caused by water vapor absorption is compensated to obtain the corrected voltage signal after eliminating water vapor interference.

[0026] As a preferred technical solution of the present invention, it also includes a focusing lens, which is arranged below the filter.

[0027] As a preferred technical solution of the present invention, it also includes a fixing plate, an inner cavity is formed inside, a top tube connected to the inner cavity is fixedly installed on the side of the top, and a bottom tube connected to the inner cavity is fixedly installed on the side of the bottom, the infrared detector is loaded in the top tube, and the focusing lens is fixed in the bottom tube;

[0028] A switching disk is rotatably installed in the inner cavity, and a plurality of mounting grooves for mounting optical filters are evenly arranged on the switching disk.

[0029] As a preferred technical solution of the present invention, a sensor fixing housing is fixedly installed on the outer wall of the bottom cylinder, and a measuring sensor is fixed inside the sensor fixing housing.

[0030] As a preferred technical solution of the present invention, it also includes an exhaust pipe with a jet nozzle at the end;

[0031] The nozzle at the end of the exhaust pipe is inserted into the bottom tube and faces the focusing lens.

[0032] (III) Beneficial effects

[0033] Compared with the prior art, the present invention provides a sludge moisture content measurement system based on multiple infrared detection reflection bands, which has the following beneficial effects:

[0034] 1. The sludge moisture content measurement system based on multiple infrared detection reflection bands can simultaneously obtain infrared light information of multiple wavelengths by using multiple infrared detectors equipped with filters, thereby improving the accuracy and stability of moisture content measurement.

[0035] 2. The sludge moisture content measurement system based on multiple infrared detection reflection bands adds a water vapor measurement channel to obtain the absolute humidity of water vapor, and uses the absolute humidity to correct the infrared light signal, eliminating the interference caused by water vapor absorption, and can obtain more accurate moisture content measurement results.

[0036] 3. The sludge moisture content measurement system based on multiple infrared detection reflection bands can realize rapid and non-contact measurement of sludge moisture content through infrared spectroscopy technology, without sampling or destroying sludge samples, and is also conducive to online real-time monitoring. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 is a schematic diagram of a measurement system of the present invention;

[0038] Figure 2 It is an enlarged schematic diagram of the fixing plate part of the present invention;

[0039] Figure 3 is a cross-sectional view of the fixing plate portion of the present invention;

[0040] Figure 4 It is an enlarged schematic diagram of the switching disk part of the present invention;

[0041] Figure 5 A cross-sectional view of a fixing plate portion in another embodiment of the present invention;

[0042] Figure 6 It is an enlarged schematic diagram of the plug barrel part of the present invention.

[0043] In the figure: 1. carrier plate; 2. infrared light source; 3. light source bracket; 4. infrared detector; 5. filter; 6. focusing lens; 7. fixing plate; 8. inner cavity; 9. switching plate; 10. mounting groove; 11. top cylinder; 12. bottom cylinder; 13. sensor fixing housing; 14. measuring sensor; 15. vertical axis; 16. fixed bearing; 17. driving plate; 18. arc groove; 19. column groove; 20. driving shaft; 21. positioning plate; 22. eccentric plate; 23. sliding column; 24. pressure plate; 25. connecting rod; 26. piston; 27. plug cylinder; 28. supporting spring; 29. ​​intake pipe; 30. exhaust pipe. DETAILED DESCRIPTION

[0044] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0045] Embodiment 1:

[0046] See also Figure 1 , a sludge moisture content measurement system based on multiple infrared detection reflection bands, including a carrying plate 1 for carrying sludge, such as Figure 1 As shown, an infrared light source 2 is also provided to emit infrared light to irradiate the sludge;

[0047] An infrared detection array is arranged above the sludge, and the infrared detection array is composed of a plurality of infrared detectors 4. The infrared detectors 4 are provided with filters 5. The filters 5 are used to limit the infrared light band range received by the infrared detectors 4, and only allow infrared light within the band to pass through, so that the infrared detectors 4 output corresponding voltage signals, and then the signal processing module receives and processes the voltage signals output by the infrared detectors 4;

[0048] In this embodiment, the signal processing module includes a signal amplification and filtering unit, an analog-to-digital conversion unit and a data storage unit, wherein the signal amplification and filtering unit is used to receive and process the voltage signal output by the infrared detector 4, amplify the signal and remove noise interference, the analog-to-digital conversion unit is used to convert the analog signal into a high-precision digital signal, and the data storage unit is used to store the processed voltage signal.

[0049] In the present invention, the infrared detector 4 is specifically divided into a characteristic band detector and a reference band detector. The filter 5 of the characteristic band detector is used to receive infrared light affected by the absorption and scattering of sludge moisture, and output a characteristic voltage signal (such as selecting a filter 5 with a central wavelength of 1400nm and a bandwidth of 24nm). The filter 5 of the reference band detector is used to receive infrared light that is not affected by the absorption and scattering of sludge moisture, and output a reference voltage signal (such as selecting a filter 5 with a central wavelength of 1100nm and a bandwidth of 20nm). The specific selection of the filter 5 can be selected by technical personnel in this field according to measurement requirements.

[0050] The model building module builds a correlation model between the reflected light power and the water content according to the characteristic voltage signal of the characteristic band detector and the reference voltage signal of the reference band detector.

[0051] The construction of the correlation model, first, collects the voltage signal of the reflected light through the infrared detector 4, and records the voltage signal V of the characteristic band and the reference band respectively. f and V r Among them, the voltage signal of the characteristic band is affected by the moisture content of the sludge, while the signal of the reference band is used for error correction.

[0052] In order to eliminate the influence of environmental noise and other external interference, the voltage signals of the characteristic band and the reference band are differentially processed to obtain the relative change ΔV:

[0053] ΔV=V r -V f

[0054] In the present invention, a quadratic polynomial model is used to fit the relationship between the reflected light power and the moisture content. The sludge moisture content W and the voltage change ΔV can be expressed as:

[0055] W=a﹒ (ΔV) 2 +b﹒ (ΔV)+c

[0056] Among them, a, b, c are the model parameters to be fitted, and W is the actual moisture content of the sludge.

[0057] By collecting a large amount of data and using regression analysis, a, b, and c can be fitted. The actual moisture content W of each sample and the corresponding voltage change ΔV are used as input data, and the least squares method is used to fit the model parameters:

[0058]

[0059] Through the above optimization, the a, b, and c values ​​can be obtained, and the fitting error of the model is small.

[0060] After the model is constructed, the model can be used to calculate the sludge moisture content. During the calculation, ΔV is substituted into the fitted model to obtain the sludge moisture content (i.e., the moisture content calculation module).

[0061] In the present invention, a water vapor measurement channel is also provided, specifically including a temperature sensor and a humidity sensor, for measuring the temperature and relative humidity in the air and calculating the absolute humidity. The absorption interference of water vapor in the air on the infrared light reflection signal can be corrected by the absolute humidity value.

[0062] The specific correction method is to determine the absorption coefficient of water vapor in a specific infrared band based on the absolute humidity value of water vapor, and compensate for the voltage attenuation caused by water vapor absorption in combination with the reference voltage signal of the reference band detector to obtain a corrected voltage signal after eliminating water vapor interference. The corrected voltage signal is used to construct a correlation model to ensure that the final reflected signal only contains the light intensity attenuation caused by water absorption on the sludge surface, thereby improving the measurement accuracy of the sludge moisture content.

[0063] Embodiment 2:

[0064] See also Figure 1-Figure 4 Based on the first embodiment, in this embodiment, the infrared light source 2 can be a continuous spectrum infrared lamp or a laser of a specific wavelength. The infrared light source 2 is mounted on an adjustable light source bracket 3, which can adjust relevant parameters such as height and angle.

[0065] like Figure 1 As shown, a focusing lens 6 is also provided below the filter 5 to play a role similar to a magnifying glass, thereby increasing the light intensity entering the effective detection area of ​​the infrared detector 4 .

[0066] In the present invention, Figure 3 As shown, a fixing plate 7 is also provided, an inner cavity 8 is formed inside, a top cylinder 11 connected to the inner cavity 8 is fixedly installed on the side of the top, a bottom cylinder 12 connected to the inner cavity 8 is fixedly installed on the side of the bottom, the infrared detector 4 is loaded in the top cylinder 11, the focusing lens 6 is fixed in the bottom cylinder 12, a switching disk 9 is rotatably installed in the inner cavity 8, and a plurality of mounting grooves 10 for mounting the optical filter 5 are evenly opened on the switching disk 9, and the optical filter 5 is installed in the mounting groove 10;

[0067] By rotating the switching disk 9 , the optical filters 5 at different positions on the switching disk 9 can correspond to the infrared detector 4 and the focusing lens 6 , thereby realizing convenient switching of the optical filters 5 .

[0068] like Figure 3 As shown, a sensor fixing shell 13 is fixedly installed on the outer wall of the bottom tube 12, and a measuring sensor 14 is fixed in the sensor fixing shell 13. The measuring sensor 14 is a temperature sensor and a humidity sensor, which is used to measure the temperature and relative humidity in the air and calculate the absolute humidity. Furthermore, the absorption interference of water vapor in the air on the infrared light reflection signal can be corrected through the absolute humidity value.

[0069] like Figure 5 As shown, an exhaust pipe 30 with a nozzle connected to the end is also provided. The nozzle at the end of the exhaust pipe 30 is inserted into the bottom tube 12 and faces the focusing lens 6. The gas ejected is sprayed on the bottom of the focusing lens 6, thereby achieving effective cleaning of the focusing lens 6. Since the filter 5 is always located in the inner cavity 8 and the infrared detector 4 is fixed in the top tube 11 and is not in contact with the external environment, no cleaning is required.

[0070] Embodiment three:

[0071] See also Figure 5 and Figure 6 Based on the first and second embodiments, this embodiment specifically provides a mechanism for driving the switching disk 9 to rotate, such as Figure 5 As shown:

[0072] A vertical shaft 15 is fixedly installed at the center of the bottom of the switching disk 9. The vertical shaft 15 is fixed by a fixed bearing 16. A driving disk 17 is fixedly connected to the bottom end of the vertical shaft 15. Column grooves 19 are evenly opened on the driving disk 17, and arc grooves 18 are formed between adjacent column grooves 19.

[0073] In addition, a drive shaft 20 driven by a motor (not shown in the figure) is provided, and a positioning plate 21 and an eccentric plate 22 are fixedly mounted on the drive shaft 20, the positioning plate 21 corresponds to the arc groove 18, and a sliding column 23 is fixedly mounted on the eccentric plate 22, and the sliding column 23 can slide into or out of the column groove 19;

[0074] When the motor drives the driving shaft 20 to rotate, the driving shaft 20 will also synchronously drive the positioning disk 21 and the eccentric disk 22 to rotate. When the eccentric disk 22 rotates, it can slide into a column groove 19 through the sliding column 23 thereon, and then drive the driving disk 17 to rotate a certain angle, and then slide out of the column groove 19, thereby realizing the rotation control of the directional angle of the driving disk 17, and then realizing the switching of different filters 5.

[0075] The positioning plate 21 serves to position the driving plate 17 . Meanwhile, a groove is formed on the positioning plate 21 to allow the “sharp corner” of the driving plate 17 to pass through.

[0076] In the present invention, Figure 6 As shown, a plug cylinder 27 is fixedly installed at the bottom of the fixed plate 7, and a piston 26 is movably arranged in the plug cylinder 27. One side of the piston 26 is supported by a support spring 28, and the other side is fixedly connected to a pressure plate 24 through a connecting rod 25. The pressure plate 24 is arranged close to the eccentric disk 22. When the eccentric disk 22 rotates, it can push the pressure plate 24 cyclically.

[0077] In this embodiment, an air inlet pipe 29 is connected through the plug tube 27, and a one-way air inlet valve is provided on the air inlet pipe 29. An exhaust pipe 30 is also connected through the plug tube 27, and a one-way exhaust valve is provided on the exhaust pipe 30.

[0078] When the eccentric disk 22 rotates and cyclically pushes the pressure plate 24, the movement of the piston 26 can be used to pump the air sucked into the intake pipe 29 out from the nozzle at the end of the exhaust pipe 30, thereby achieving effective cleaning of the focusing lens 6 without the need for an additional gas generating device or an additional electronic control system.

[0079] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A sludge moisture content measurement system based on multiple infrared detection reflection bands, comprising a carrying plate (1) for carrying sludge, characterized in that: Also includes: An infrared light source (2) for emitting infrared light to irradiate the sludge; An infrared detection array is composed of a plurality of infrared detectors (4), wherein the infrared detectors (4) are provided with filters (5), wherein the filters (5) are used to limit the wavelength range of infrared light received by the infrared detectors (4), and only allow infrared light within the wavelength range to pass through, thereby causing the infrared detectors (4) to output a corresponding voltage signal; A signal processing module, used for receiving and processing a voltage signal output by the infrared detector (4); A model building module, used to build a correlation model between reflected light power and water content; The moisture content calculation module calculates the sludge moisture content based on the correlation model.

2. The sludge moisture content measurement system based on multiple infrared detection reflection bands according to claim 1 is characterized by: The signal processing module comprises: Signal amplification and filtering unit: used for receiving and processing the voltage signal output by the infrared detector (4), amplifying the signal and removing noise interference; Analog-to-digital conversion unit: used to convert analog signals into high-precision digital signals; The data storage unit is used to store the processed voltage signal.

3. A sludge moisture content measurement system based on multiple infrared detection reflection bands according to claim 1 or 2, characterized in that: The infrared detector (4) comprises: A characteristic band detector, whose filter (5) is used to receive infrared light affected by the absorption and scattering of sludge water, and output a characteristic voltage signal; A reference band detector, whose filter (5) is used to receive infrared light that is not affected by sludge moisture absorption and scattering, and output a reference voltage signal; The model building module builds a correlation model between the reflected light power and the water content according to the characteristic voltage signal of the characteristic band detector and the reference voltage signal of the reference band detector.

4. The sludge moisture content measurement system based on multiple infrared detection reflection bands according to claim 1 is characterized in that: Also includes: A water vapor measurement channel, including a temperature sensor and a humidity sensor, for measuring the temperature and relative humidity in the air and calculating the absolute humidity; The absorption interference of water vapor in the air on the infrared light reflection signal is corrected by the absolute humidity value.

5. The sludge moisture content measurement system based on multiple infrared detection reflection bands according to claim 4 is characterized in that: The calibration process includes: According to the absolute humidity value of water vapor, the absorption coefficient of water vapor in a specific infrared band is determined. Combined with the reference voltage signal of the reference band detector, the voltage attenuation caused by water vapor absorption is compensated to obtain the corrected voltage signal after eliminating water vapor interference.

6. The sludge moisture content measurement system based on multiple infrared detection reflection bands according to claim 1 is characterized by: It also includes a focusing lens (6) which is arranged below the filter (5).

7. The sludge moisture content measurement system based on multiple infrared detection reflection bands according to claim 6 is characterized by: It also includes a fixing plate (7) having an inner cavity (8) formed therein, a top tube (11) connected to the inner cavity (8) fixedly mounted on the top side, and a bottom tube (12) connected to the inner cavity (8) fixedly mounted on the bottom side, the infrared detector (4) being loaded in the top tube (11), and the focusing lens (6) being fixed in the bottom tube (12); A switching disk (9) is rotatably mounted in the inner cavity (8), and a plurality of mounting grooves (10) for mounting optical filters (5) are evenly arranged on the switching disk (9).

8. The sludge moisture content measurement system based on multiple infrared detection reflection bands according to claim 7 is characterized by: A sensor fixing housing (13) is fixedly mounted on the outer wall of the bottom cylinder (12), and a measuring sensor (14) is fixed inside the sensor fixing housing (13).

9. The sludge moisture content measurement system based on multiple infrared detection reflection bands according to claim 7 is characterized by: It also includes an exhaust pipe (30) with an air jet nozzle at the end; The nozzle at the end of the exhaust pipe (30) is inserted into the bottom tube (12) and faces the focusing lens (6).

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