A three-dimensional turbidity measurement method and measurement system based on spatial scanning

Abstract

The present invention discloses a three-dimensional turbidity measurement method and measurement system based on space scanning, which establishes a three-dimensional xyz coordinate system in the three-dimensional space to be measured, scans and measures the xoz coordinate plane and the yoz coordinate plane respectively, and obtains gridded turbidity data; now Coordinate plane and summer Calculate the turbidity in three dimensions from the plane or one-dimensional turbidity data of the coordinate plane C NTU The present invention can process the now Coordinate plane and summer The turbidity data of the coordinate plane can be quickly calculated to obtain the turbidity of the three-dimensional space that reflects the overall measurement situation. On the other hand, the present invention can process the turbidity of the three-dimensional space by a single-dimensional calculation method. now Coordinate plane and summer The turbidity data on the coordinate plane can be used to more accurately calculate the turbidity in three-dimensional space, meeting the high-precision requirements of turbidity measurement in three-dimensional space, solving the limitations of single-point measurement, and having good practicality.

Description

Technical Field

[0001] The present invention belongs to the technical field of water quality measurement, and in particular relates to a three-dimensional turbidity measurement method and a measurement system based on space scanning. Background Art

[0002] Turbidity, also known as turbidity, is a measure of the reduction in liquid transparency due to the presence of substances in the water that scatter light. The turbidity of water reflects the content of suspended matter such as sediment, clay, fine organic and inorganic matter, soluble colored organic compounds, plankton and other microorganisms. Generally speaking, the higher the turbidity, the lower the cleanliness of the water. Turbidity measurement methods include transmission method and scattering method. Current turbidity measuring devices generally use the scattering method to measure, and the concentration of suspended matter is determined by measuring the intensity of light passing through the suspended particle medium. Suspended and colloidal particles in water will scatter and absorb light passing through the sample. The scattering phenomenon of light produces turbidity. The scattering characteristics of light by particulate matter in the sample are used to characterize turbidity. The unit of measurement result is NTU (Nephelometric Turbidity Units). For example Figure 1 As shown, a stable beam of light is passed through a sample cell containing the sample to be tested. The sensor is positioned perpendicular to the emitted light and measures the intensity of the scattered light. The intensity of the scattered light generated when the beam enters the sample is proportional to the turbidity in the sample within a certain concentration range.

[0003] However, existing turbidity sensors use single-point monitoring, which has spatial limitations. For example, traditional fixed turbidity sensors (such as pipe-embedded or submerged probes) can only obtain local data and are difficult to capture three-dimensional spatial turbidity gradient changes in the water body caused by suspended particle sedimentation, turbulent disturbances or pollutant diffusion. When the sediments at the bottom of the river are resuspended, the turbidity difference between the surface and deep layers is significant, and single-point data can easily lead to misjudgment of the overall water quality. Secondly, these sensors are not adaptable enough in dynamic environments. The turbidity of the water body is affected by multiple factors such as flow rate, temperature, and biological activity, showing dynamic inhomogeneity, making it difficult to achieve vertical stratification or horizontal gridding continuous monitoring. In addition, in complex scenarios, such as high turbidity environments, traditional optical sensors are easily interfered by particle scattering, and measurement errors increase sharply with increasing turbidity. At the same time, interference sources such as bubbles and algae further reduce data reliability. Summary of the Invention

[0004] The purpose of the present invention is to provide a three-dimensional turbidity measurement method and measurement system based on spatial scanning, which reconstructs the three-dimensional turbidity field through detection data, thereby effectively improving the accuracy and comprehensiveness of turbidity detection.

[0005] The present invention is mainly achieved through the following technical solutions:

[0006] A three-dimensional turbidity measurement method based on spatial scanning comprises the following steps:

[0007] Step S1: Establish a three-dimensional xyz coordinate system in the three-dimensional space to be measured;

[0008] Step S2: Scan and measure the xoz coordinate plane and the yoz coordinate plane respectively, and obtain gridded turbidity data;

[0009] Step S3: Based on the planar or single-dimensional turbidity data of the xoz coordinate plane and the yoz coordinate plane, calculate the turbidity C in the three-dimensional space. NTU .

[0010] Preferably, in step S1, the turbidity meter can perform scanning measurement based on Cartesian coordinates.

[0011] Preferably, the present invention can perform gridded measurement of turbidity on the xoz coordinate plane and the yoz coordinate plane using a static sensor. The present invention can also obtain gridded turbidity data by performing plane step-by-step scanning detection using a dynamic driven sensor.

[0012] In order to better implement the present invention, further, step S3 includes the following steps:

[0013] Step A1: Based on the plane turbidity data of the xoz coordinate plane, calculate the average turbidity value of the xoz coordinate plane

[0014] Step A2: Based on the plane turbidity data of the yoz coordinate plane, calculate the average turbidity value of the yoz coordinate plane

[0015] Step A3: Based on steps A1 and A2, calculate the turbidity C in the three-dimensional space NTU for:

[0016]

[0017] in:

[0018]

[0019] Where: w xoz is the turbidity weighting coefficient of the xoz coordinate plane;

[0020] w yoz is the turbidity weighting coefficient of the yoz coordinate plane;

[0021] is the mean deviation of turbidity in the xoz coordinate plane;

[0022] is the average turbidity deviation in the yoz coordinate plane.

[0023] In order to better implement the present invention, further, in step A1, the average turbidity value of the xoz coordinate plane is for:

[0024]

[0025] In step A2, the average turbidity value of the yoz coordinate plane for:

[0026]

[0027] Where: l is the number of subdivision steps on the x-axis;

[0028] m is the number of subdivision steps on the y-axis;

[0029] n is the number of subdivision steps on the z axis;

[0030] C ij It is the turbidity data of the xoz coordinate plane or the yoz coordinate plane.

[0031] In order to better implement the present invention, further, in step A3, the uncertainty u caused by the plane turbidity data measurement is NTU for:

[0032]

[0033] In order to better implement the present invention, further, step S3 includes the following steps:

[0034] Step B1: Calculate the turbidity value C of the xoz plane based on the turbidity data of the x dimension of the xoz coordinate plane xoz ;

[0035] Step B2: Calculate the turbidity value C of the yoz plane based on the turbidity data of the y dimension of the yoz coordinate plane yoz ;

[0036] Step B3: Based on steps B1 and B2, calculate the turbidity C in the three-dimensional space NTU for:

[0037]

[0038] in:

[0039]

[0040] Where: w ix is the weight coefficient of the i-th x dimension of the xoz coordinate plane;

[0041] w iy is the weight coefficient of the i-th y dimension of the yoz coordinate plane;

[0042] is the average turbidity value of the i-th x dimension of the xoz coordinate plane;

[0043] is the average turbidity value of the i-th y dimension of the yoz coordinate plane;

[0044] n is the number of subdivision steps on the z-axis.

[0045] In order to better implement the present invention, further, in step B3, the uncertainty u caused by the single-dimensional turbidity data measurement is NTU for:

[0046]

[0047] Where: u xoz is the turbidity C in the xoz coordinate plane xoz uncertainty;

[0048] u yoz is the turbidity C in the yoz coordinate plane yoz uncertainty.

[0049] In order to better implement the present invention, further, in step S2, multi-band measurement is used to measure the turbidity data of the xoz coordinate plane and the yoz coordinate plane; wherein the measured turbidity C MW for:

[0050]

[0051] Where: r is the wavelength of monochromatic light;

[0052] α r The wavelength is λ r Weight coefficient of monochromatic light;

[0053] Measure the wavelength λ for the monochromatic light model r Turbidity of monochromatic light;

[0054] r is the type of monochromatic light.

[0055] In order to better realize the present invention, further, the turbidity data of the xoz coordinate plane and the yoz coordinate plane are measured using the dual bands of 550nm and 860nm; wherein the measured turbidity C DM for:

[0056]

[0057] Where: α is the weight coefficient of 860nm light;

[0058] Measure the turbidity of 860nm light for the monochromatic light model;

[0059] β is the weight coefficient of 550nm light;

[0060] Measures the turbidity of 550nm light for the monochromatic light model.

[0061] In order to better realize the present invention, further, hexamethylenetetramine C6H 12 Standard turbidity solutions with different concentrations were prepared with N4 and hydrazine sulfate N2H6SO4. Then, the turbidity values ​​were measured respectively using the monochromatic light 90° scattering measurement model, and the weight coefficients of each measurement band were obtained through matrix calculation.

[0062] The present invention is mainly achieved through the following technical solutions:

[0063] A three-dimensional turbidity measurement system based on spatial scanning is based on the above-mentioned three-dimensional turbidity measurement method based on spatial scanning, comprising a turbidity measuring instrument and a data processing module, wherein the data processing module comprises a multi-band turbidity measurement unit, a scanning data acquisition unit, a planar data processing unit, and a single-dimensional data processing unit;

[0064] The turbidity meter includes a multi-band light source array and a 90° detector and a 180° detector corresponding to each band light source. The 90° detector and the 180° detector are respectively used to measure the 90° direction light intensity and the transmitted light intensity of the band light source; the turbidity meter is used to calculate the turbidity measured in each band using the 90° scattered light and the 180° transmitted light intensity, and detect the turbidity in water based on the multi-band measurement method;

[0065] The scanning data acquisition unit is used to collect gridded turbidity data of three-dimensional scanning;

[0066] The plane data processing unit is used to calculate the turbidity C in three-dimensional space based on the plane turbidity data of the xoz coordinate plane and the yoz coordinate plane. NTU ;

[0067] The single-dimensional data processing unit is used to calculate the turbidity C in three-dimensional space based on the turbidity data of the x-dimension and y-dimension of the xoz coordinate plane and the yoz coordinate plane. NTU .

[0068] The beneficial effects of the present invention are as follows:

[0069] The present invention obtains gridded turbidity data by scanning and measuring the turbidity of the xoz coordinate plane and the yoz coordinate plane of the three-dimensional space to be measured, and calculates the turbidity of the three-dimensional space based on the plane turbidity data or the single-dimensional turbidity data, thereby effectively improving the accuracy of turbidity measurement, overcoming the limitations of single-point measurement, and having good practicality.

[0070] The present invention processes turbidity data from the xoz and yoz coordinate planes using a planar calculation method, allowing rapid calculation of turbidity in a three-dimensional space reflecting the overall measurement situation. Alternatively, the present invention processes turbidity data from the xoz and yoz coordinate planes using a single-dimensional calculation method, allowing more accurate calculation of turbidity in a three-dimensional space. This satisfies the high-precision requirements for turbidity measurement in a three-dimensional space and demonstrates excellent practicality.

[0071] This invention uses dual-band or multi-band scanning to measure turbidity across a surface, further increasing the accuracy of single-point turbidity data. This improves upon the traditional 90° scattering method, employing both 90° scattered and 180° transmitted light intensity (traditionally, incident light intensity) for measurement. This method is independent of incident light intensity (light source). This overcomes the need for corrections in traditional sensors, which require constant correction of the light source drive current to maintain light source (incident light intensity) stability and ensure sensor consistency, as the light source decays over time. BRIEF DESCRIPTION OF THE DRAWINGS

[0072] Figure 1 Schematic diagram of the principle of turbidity measurement of turbidity meter;

[0073] Figure 2 Flowchart of the three-dimensional turbidity measurement method based on spatial scanning in Example 1;

[0074] Figure 3 Flowchart of the three-dimensional turbidity measurement method based on spatial scanning in Example 2;

[0075] Figure 4 This is the principle block diagram of the three-dimensional turbidity measurement system based on spatial scanning. DETAILED DESCRIPTION

[0076] Example 1:

[0077] A three-dimensional turbidity measurement method based on space scanning is to establish a three-dimensional xyz coordinate system in the three-dimensional space to be measured, scan and measure the xoz coordinate plane and the yoz coordinate plane respectively and obtain gridded turbidity data; the turbidity C of the three-dimensional space is calculated based on the turbidity data of the xoz coordinate plane and the yoz coordinate plane. NTU .

[0078] Preferably, if Figure 2 As shown, the specific steps include:

[0079] Step 1: Data Scan:

[0080] The turbidity scan adopts step-by-step plane scanning. The plane scanning process first performs the x-axis motion scanning process, then the y-axis motion scanning process, then moves the z-axis, and then repeats the plane scanning.

[0081] (1) Obtain xoz coordinate plane scanning data through spatial scanning:

[0082]

[0083] Where: l is the number of subdivision steps on the x-axis;

[0084] n is the number of subdivision steps on the z-axis.

[0085] (2) Obtain yoz coordinate plane scanning data through spatial scanning:

[0086]

[0087] Where: m is the number of subdivision steps on the y-axis;

[0088] n is the number of subdivision steps on the z-axis.

[0089] Step 2: Calculate the turbidity C in three-dimensional space NTU :

[0090] Use plane calculation method to quickly calculate turbidity value: use plane data to calculate, calculate the arithmetic mean, standard deviation, average deviation, weighting coefficient and turbidity C in three-dimensional space in turn NTU .

[0091] Step A1: Based on the plane turbidity data of the xoz coordinate plane, calculate the average turbidity value of the xoz coordinate plane

[0092] 1) Calculate the arithmetic mean of the turbidity scan data in the xoz coordinate plane

[0093]

[0094] in: is the arithmetic mean of the turbidity scanning data in the xoz coordinate plane;

[0095] C ij is the process operation data, C ij∈ C nl ;

[0096] ij is process data and has no practical meaning;

[0097] l is the number of subdivision steps on the x-axis;

[0098] n is the number of subdivision steps on the z-axis.

[0099] 2) Calculate the standard deviation

[0100]

[0101] Where: xoz is the standard deviation of turbidity in the xoz coordinate plane;

[0102] is the arithmetic mean of the turbidity scanning data in the xoz coordinate plane;

[0103] C ij is the process operation data, C ij∈ C nl ;

[0104] ij is process data and has no practical meaning;

[0105] l is the number of subdivision steps on the x-axis;

[0106] n is the number of subdivision steps on the z axis;

[0107] 3) Calculate the average deviation

[0108]

[0109] Where: xoz is the standard deviation of turbidity in the xoz coordinate plane;

[0110] is the average deviation of turbidity in the xoz coordinate plane;

[0111] l is the number of subdivision steps on the x-axis;

[0112] n is the number of subdivision steps on the z-axis.

[0113] Step A2: Based on the plane turbidity data of the yoz coordinate plane, calculate the average turbidity value of the yoz coordinate plane

[0114] 1) Calculate the arithmetic mean of the turbidity scanning data in the yoz coordinate plane

[0115]

[0116] in: is the arithmetic mean of the turbidity scanning data in the yoz coordinate plane;

[0117] C ij is the process operation data, C ij∈ C mn ;

[0118] The ij process data has no practical meaning;

[0119] m is the number of subdivision steps on the y-axis;

[0120] n is the number of subdivision steps on the z axis;

[0121] 2) Calculate the standard deviation

[0122]

[0123] Where: yoz is the standard deviation of turbidity in the yoz coordinate plane;

[0124] is the arithmetic mean of the turbidity scanning data in the xoz coordinate plane;

[0125] C ij is the process operation data, C ij∈ C nl ;

[0126] ij is process data and has no practical meaning;

[0127] 3) Calculate the average deviation

[0128]

[0129] Where: yoz is the standard deviation of turbidity in the yoz coordinate plane;

[0130] is the average deviation of turbidity in the yoz coordinate plane;

[0131] 4) Calculation method of weighting coefficient:

[0132]

[0133] is the average deviation of turbidity in the xoz coordinate plane;

[0134] is the average deviation of turbidity in the yoz coordinate plane;

[0135] w xoz is the weighting coefficient of turbidity in the xoz coordinate plane;

[0136] w yoz is the weighting coefficient of turbidity in the yoz coordinate plane;

[0137] Step A3: Based on steps A1 and A2, calculate the turbidity C in the three-dimensional space NTU for:

[0138]

[0139] is the arithmetic mean of the turbidity scanning data in the xoz coordinate plane;

[0140] is the arithmetic mean of the turbidity scanning data in the xoz coordinate plane;

[0141] Step 3: Weighted average uncertainty assessment:

[0142]

[0143] Where: u NTU Uncertainty caused by measurement (Class A).

[0144] The present invention scans and measures the turbidity of the xoz and yoz coordinate planes of the three-dimensional space to be measured, obtaining gridded turbidity data. The turbidity in the three-dimensional space is then calculated based on the surface turbidity of adjacent xoz and yoz coordinate planes. This effectively improves the accuracy of turbidity measurement and overcomes the limitations of single-point measurement. By processing the turbidity data of the xoz and yoz coordinate planes using a planar calculation method, the present invention can quickly calculate the turbidity in the three-dimensional space that reflects the overall measurement situation, thus having good practicality.

[0145] Example 2:

[0146] A three-dimensional turbidity measurement method based on space scanning is to establish a three-dimensional xyz coordinate system in the three-dimensional space to be measured, scan and measure the xoz coordinate plane and the yoz coordinate plane respectively to obtain gridded turbidity data; the turbidity C in the three-dimensional space is calculated based on the single-dimensional turbidity data of the xoz coordinate plane and the yoz coordinate plane. NTU .

[0147] Preferably, if Figure 3 As shown, the specific steps include:

[0148] Step 1: Data scanning is the same as that described in Example 1, so it will not be repeated here.

[0149] Step 2: Use the single-dimensional calculation method to accurately calculate the turbidity value C NTU : Use the data of the x-axis and y-axis to perform subdivision calculations and then perform overall calculations. Specifically, calculate the single-dimensional data of each plane based on the single-dimensional calculation model - calculate the arithmetic mean, standard deviation, average deviation, and weighting coefficient in sequence; finally, integrate the different single-dimensional data to obtain the turbidity C in three-dimensional space NTU .

[0150] The single-dimensional calculation model is:

[0151] a1. Calculate the arithmetic mean

[0152]

[0153] Where: g is the number of subdivision steps in a single dimension, g∈{lm};

[0154] It is the arithmetic mean obtained from a single scan of a single dimension;

[0155] C i Calculates data for the subdivision measurement process of single-dimensional scanning, C i ∈C nl ∪C nm ;

[0156] i is process data and has no practical meaning.

[0157] a2. Calculate the standard deviation

[0158]

[0159] Where: g is the standard deviation of turbidity in a single dimension.

[0160] a3. Calculate the average deviation

[0161]

[0162] in: is the average deviation of turbidity in a single dimension.

[0163] a4. Single dimension weighting coefficient

[0164]

[0165] Preferably, the specific steps of the one-dimensional calculation method are as follows:

[0166] Step B1: Calculate the turbidity value C of the xoz plane based on the turbidity data of the x dimension of the xoz coordinate plane xoz ;

[0167] (1) Obtain the dimensional data on the xoz coordinate plane through a single-dimensional calculation model:

[0168] The arithmetic mean is:

[0169]

[0170] The standard deviation is:

[0171] [σ 1x σ 2x … σ nx ]

[0172] The weighting coefficient is:

[0173] [w 1x w 2x … w nx (2) Obtain the y-dimensional data on the yoz coordinate plane through the unit dimension calculation model:

[0174] The arithmetic mean is

[0175]

[0176] The standard deviation is

[0177] [σ 1y σ 2y … σ ny ]

[0178] Weighting coefficient

[0179] [w 1y w 2y … w ny ]

[0180] (3) Calculate the data of xoz coordinate plane scanning:

[0181]

[0182] Where: C xoz Turbidity calculated for the xoz coordinate plane;

[0183] w ix is the single-dimensional weight coefficient of the xoz coordinate plane, w ix ∈w nx ;

[0184] is the single-dimensional turbidity scan average value of the xoz coordinate plane,

[0185] 2) Uncertainty data is:

[0186]

[0187] Where: u xoz Turbidity C calculated for the xoz coordinate plane xoz uncertainty;

[0188] w ix is the single-dimensional weight coefficient w of the xoz coordinate plane ix ∈w nx ;

[0189] Step B2: Calculate the turbidity value C of the yoz plane based on the turbidity data of the y dimension of the yoz coordinate plane yoz ;

[0190]

[0191] Where: w iy is the single-dimensional weight coefficient of the yoz coordinate plane, w iy ∈w ny ;

[0192] is the single-dimensional turbidity scan average value of the yoz coordinate plane,

[0193] The uncertainty data is:

[0194]

[0195] Where: u yoz is the turbidity C in the yoz coordinate plane yoz uncertainty;

[0196] Step B3: Based on steps B1 and B2, calculate the turbidity C in the three-dimensional space NTU for:

[0197]

[0198] Where: C xoz is the turbidity value of the xoz coordinate plane;

[0199] C yoz is the turbidity calculated in the yoz coordinate plane;

[0200] Step 3: The uncertainty caused by the measurement is:

[0201]

[0202] The present invention scans and measures the turbidity of the xoz and yoz coordinate planes of the three-dimensional space to be measured, obtaining gridded turbidity data, and calculating the turbidity of the three-dimensional space based on the surface turbidity of adjacent xoz and yoz coordinate planes. This effectively improves the accuracy of turbidity measurement and overcomes the limitations of single-point measurement. The present invention can process the turbidity data of the xoz and yoz coordinate planes through a single-dimensional calculation method, and can more accurately calculate the turbidity of the three-dimensional space, meeting the high-precision requirements of turbidity measurement in three-dimensional space, and has good practicality.

[0203] Example 3:

[0204] This embodiment is optimized based on embodiment 1 or 2. Figure 1As shown, turbidity measurement is based on light scattering theory, using dual bands of 550nm (visible light band) and 860nm (near infrared band) to measure turbidity data in the xoz coordinate plane and yoz coordinate plane. Visible light band measurement is sensitive to dissolved organic matter and easily affected by chromatic interference, while near infrared band measurement is less affected by color and is suitable for suspended particle measurement. Combining the scattered light intensity ratio or difference of the two bands to design a formula can effectively separate the interference between color and turbidity. The specific calculation formula is as follows:

[0205]

[0206] Where: C DM The turbidity of the solution is measured by dual-band scanning;

[0207] α is the weight coefficient of 860nm light;

[0208] Measure the turbidity of 860nm light for the monochromatic light model;

[0209] β is the weight coefficient of 550nm light;

[0210] Measures the turbidity of 550nm light for the monochromatic light model.

[0211] Preferably, the weight coefficient is measured as follows:

[0212] Hexamethylenetetramine (C6H 12 N4) and hydrazine sulfate (N2H6SO4) to prepare standard turbidity solutions (referred to as standard solutions) of different concentrations. Standard solutions can also be purchased on the market as follows:

[0213]

[0214] The turbidity values ​​measured by the monochromatic light 90° scattering measurement model are:

[0215]

[0216] Establish weight coefficients:

[0217]

[0218] The weight value obtained by matrix operation is:

[0219] w=(x T x) -1 x T y;

[0220] Where: α is the weight coefficient of 860nm light;

[0221] β is the weight coefficient of 550nm light;

[0222] n is the number of solutions with different concentrations, n>2;

[0223] w is the weight coefficient matrix;

[0224] x is the matrix of turbidity values ​​of the measured solution;

[0225] y is the turbidity value matrix of the standard substance.

[0226] The rest of this embodiment is the same as that of Embodiment 1 or 2, and therefore will not be described in detail.

[0227] Example 4:

[0228] This embodiment is an optimization based on embodiment 1 or 2, using multi-band measurement of turbidity data in the xoz coordinate plane and the yoz coordinate plane. The specific calculation formula is as follows:

[0229]

[0230] Where: C MW The turbidity of the solution is measured by multi-band scanning;

[0231] λ r is the wavelength of monochromatic light;

[0232] α r The wavelength is λ r Weight coefficient of monochromatic light;

[0233] Measure the wavelength λ for the monochromatic light model r Turbidity of monochromatic light;

[0234] r is the type of monochromatic light;

[0235] Preferably, the weight coefficient is measured as follows:

[0236] Hexamethylenetetramine (C6H 12 N4) and hydrazine sulfate (N2H6SO4) to prepare standard turbidity solutions (referred to as standard solutions) of different concentrations. Standard solutions can also be purchased on the market as follows:

[0237]

[0238] The turbidity values ​​measured by the monochromatic light 90° scattering measurement model are:

[0239]

[0240] Establish weight coefficients:

[0241]

[0242] The weight value obtained by matrix operation is:

[0243] w=(x T x) -1 x T y;

[0244] n is the number of solutions with different concentrations, and n>m;

[0245] r is the type of monochromatic light;

[0246] w is the weight coefficient matrix;

[0247] λ r is the wavelength of monochromatic light;

[0248] x is the matrix of turbidity values ​​of the measured solution;

[0249] y is the turbidity value matrix of the standard substance.

[0250] The rest of this embodiment is the same as that of Embodiment 1 or 2, and therefore will not be described in detail.

[0251] Example 5:

[0252] A three-dimensional turbidity measurement system based on spatial scanning, such as Figure 4 As shown, the three-dimensional turbidity measurement method based on spatial scanning is carried out, including a turbidity measuring instrument and a data processing module, wherein the data processing module includes a multi-band turbidity measurement unit, a scanning data acquisition unit, a plane data processing unit and a single-dimensional data processing unit.

[0253] The scanning data acquisition unit is used to collect gridded turbidity data of three-dimensional scanning;

[0254] The plane data processing unit is used to calculate the turbidity C in three-dimensional space based on the plane turbidity data of the xoz coordinate plane and the yoz coordinate plane. NTU ;

[0255] The single-dimensional data processing unit is used to calculate the turbidity C in three-dimensional space based on the turbidity data of the x-dimension and y-dimension of the xoz coordinate plane and the yoz coordinate plane. NTU .

[0256] The turbidity meter includes a light source module, as well as a 90° detector and a 180° detector. The 90° detector and the 180° detector are used to measure the light intensity at 90° and the transmitted light intensity of the wavelength band light source, respectively. The turbidity meter is used to calculate the turbidity measured in each wavelength band using the 90° scattered light and 180° transmitted light intensities.

[0257] like Figure 1 As shown, the measurement model of the turbidity meter is:

[0258]

[0259] Where: C is the turbidity of the solution;

[0260] k NTU is the turbidity instrument correction factor;

[0261] I S The light intensity is at 90° direction;

[0262] I t is the intensity of transmitted light.

[0263] Preferably, the light source module is a multi-band light source array, and the turbidity meter is provided with a 90° detector and a 180° detector corresponding to each band light source. The turbidity meter is used to calculate the turbidity measured in each band using 90° scattered light and 180° transmitted light intensity, and detect the turbidity in water based on a multi-band measurement method.

[0264] This invention uses dual-band or multi-band scanning to measure turbidity across a surface, further increasing the accuracy of single-point turbidity data. This improves upon the traditional 90° scattering method, employing both 90° scattered and 180° transmitted light intensity (traditionally, incident light intensity) for measurement. This method is independent of incident light intensity (light source). This overcomes the need for corrections in traditional sensors, which require constant correction of the light source drive current to maintain light source (incident light intensity) stability and ensure sensor consistency, as the light source decays over time.

[0265] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Any simple modification or equivalent change made to the above embodiment based on the technical essence of the present invention shall fall within the scope of protection of the present invention.

Claims

1. A three-dimensional turbidity measurement method based on spatial scanning, characterized in that: The following steps are involved: Step S1: Establish a three-dimensional xyz coordinate system in the three-dimensional space to be measured; Step S2: Scan and measure the xoz coordinate plane and the yoz coordinate plane respectively, and obtain gridded turbidity data; Step S3: Based on the plane turbidity data of the xoz coordinate plane and the yoz coordinate plane, the turbidity C in the three-dimensional space is calculated. NTU ; The following steps are involved: Step A1: Based on the plane turbidity data of the xoz coordinate plane, calculate the average turbidity value of the xoz coordinate plane Step A2: Based on the plane turbidity data of the yoz coordinate plane, calculate the average turbidity value of the yoz coordinate plane Step A3: Based on steps A1 and A2, calculate the turbidity C in the three-dimensional space NTU for: in: Where: w xoz is the turbidity weighting coefficient of the xoz coordinate plane; w yoz is the turbidity weighting coefficient of the yoz coordinate plane; is the mean deviation of turbidity in the xoz coordinate plane; is the mean deviation of turbidity in the yoz coordinate plane; Alternatively, step S3: Based on the single-dimensional turbidity data of the xoz coordinate plane and the yoz coordinate plane, the turbidity C in the three-dimensional space is calculated. NTU ; including the following steps: Step B1: Calculate the turbidity value C of the xoz plane based on the turbidity data of the x dimension of the xoz coordinate plane xoz ; Step B2: Calculate the turbidity value C of the yoz plane based on the turbidity data of the y dimension of the yoz coordinate plane yoz ; Step B3: Based on steps B1 and B2, calculate the turbidity C in the three-dimensional space NTU for: in: Where: w ix is the weight coefficient of the i-th x dimension of the xoz coordinate plane; w iy is the weight coefficient of the i-th y dimension of the yoz coordinate plane; is the average turbidity value of the i-th x dimension of the xoz coordinate plane; is the average turbidity value of the i-th y dimension of the yoz coordinate plane; n is the number of subdivision steps on the z-axis.

2. The three-dimensional turbidity measurement method based on spatial scanning according to claim 1, characterized in that: In step A1, the average turbidity value of the xoz coordinate plane for: In step A2, the average turbidity value of the yoz coordinate plane for: Where: l is the number of subdivision steps on the x-axis; m is the number of subdivision steps on the y-axis; n is the number of subdivision steps on the z axis; C ij It is the turbidity data of the xoz coordinate plane or the yoz coordinate plane.

3. The three-dimensional turbidity measurement method based on spatial scanning according to claim 1, characterized in that: In step A3, the uncertainty u caused by the plane turbidity data measurement is NTU for:

4. The three-dimensional turbidity measurement method based on spatial scanning according to claim 1, characterized in that: In step B3, the uncertainty u caused by the single-dimensional turbidity data measurement is NTU for: Where: u xoz is the turbidity C in the xoz coordinate plane xoz uncertainty; u yoz is the turbidity C in the yoz coordinate plane yoz uncertainty.

5. A three-dimensional turbidity measurement method based on spatial scanning according to any one of claims 1 to 4, characterized in that: In step S2, the turbidity data of the xoz coordinate plane and the yoz coordinate plane are measured using multi-band; wherein the measured turbidity C MW for: Where: r is the wavelength of monochromatic light; α r The wavelength is λ r Weight coefficient of monochromatic light; Measure the wavelength λ for the monochromatic light model r Turbidity of monochromatic light; r is the type of monochromatic light.

6. The three-dimensional turbidity measurement method based on spatial scanning according to claim 5, characterized in that: The turbidity data of xoz coordinate plane and yoz coordinate plane were measured using dual bands of 550nm and 860nm. DM for: Where: α is the weight coefficient of 860nm light; Measure the turbidity of 860nm light for the monochromatic light model; β is the weight coefficient of 550nm light; Measures the turbidity of 550nm light for the monochromatic light model.

7. The three-dimensional turbidity measurement method based on spatial scanning according to claim 5, characterized in that: Using hexamethylenetetramine C6H 12 Standard turbidity solutions with different concentrations were prepared with N4 and hydrazine sulfate N2H6SO4. Then, the turbidity values ​​were measured respectively using the monochromatic light 90° scattering measurement model, and the weight coefficients of each measurement band were obtained through matrix calculation.

8. A three-dimensional turbidity measurement system based on spatial scanning, based on the three-dimensional turbidity measurement method based on spatial scanning according to any one of claims 1 to 7, characterized in that: It includes a turbidity measuring instrument and a data processing module, wherein the data processing module includes a multi-band turbidity measurement unit, a scanning data acquisition unit, a plane data processing unit and a single-dimensional data processing unit; The turbidity meter includes a multi-band light source array and a 90° detector and a 180° detector corresponding to each band light source. The 90° detector and the 180° detector are respectively used to measure the 90° direction light intensity and the transmitted light intensity of the band light source; the turbidity meter is used to calculate the turbidity measured in each band using the 90° scattered light and the 180° transmitted light intensity, and detect the turbidity in water based on the multi-band measurement method; The scanning data acquisition unit is used to collect gridded turbidity data of three-dimensional scanning; The plane data processing unit is used to calculate the turbidity C in three-dimensional space based on the plane turbidity data of the xoz coordinate plane and the yoz coordinate plane. NTU ; The single-dimensional data processing unit is used to calculate the turbidity C in three-dimensional space based on the turbidity data of the x-dimension and y-dimension of the xoz coordinate plane and the yoz coordinate plane. NTU .

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