Three-dimensional turbidity measuring method and measuring system based on space scanning

Abstract

The invention discloses a three-dimensional turbidity measurement method and system based on space scanning, and the method comprises the steps: building a three-dimensional xyz coordinate system in a to-be-measured three-dimensional space, respectively scanning and measuring an xoz coordinate plane and a yoz coordinate plane, and obtaining meshed turbidity data; and calculating the turbidity CNTU of the three-dimensional space based on the planar or single-dimensional turbidity data of the xoz coordinate plane and the yoz coordinate plane. According to the method, turbidity data of the xoz coordinate plane and the yoz coordinate plane can be processed through a plane calculation method, and the turbidity of the three-dimensional space reflecting the overall measurement condition can be obtained through quick calculation. On the other hand, the turbidity data of the xoz coordinate plane and the yoz coordinate plane can be processed through a one-dimensional calculation method, the turbidity of the three-dimensional space can be calculated more accurately, the requirement for high precision of turbidity measurement of the three-dimensional space is met, the limitation of single-point measurement is solved, and good practicability is achieved.

Description

Technical Field

[0001] The 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 mud, 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 measurement 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 the water will scatter and absorb light passing through the sample. The scattering phenomenon of light produces turbidity. The scattering characteristics of particulate matter in the sample to characterize turbidity, and the measurement result unit is NTU (Nephelometric Turbidity Units). For example tú1 As shown in the figure, a stable light source is used to pass through the sample pool containing the sample to be tested, and the sensor is located at a position perpendicular to the emitted light to measure the scattered light intensity. The intensity of the scattered light generated when the light 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 the 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 the measurement error increases sharply with the increase of turbidity. At the same time, interference sources such as bubbles and algae further reduce the reliability of the data. Summary of the invention

[0004] The object 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: A three-dimensional turbidity measurement method based on spatial scanning comprises the following steps: Step S1: Create a three-dimensional space in the three-dimensional space to be tested xyz Coordinate system; Step S2: Scan and measure separately now Coordinate plane and summer Coordinate plane, and obtain gridded turbidity data; Step S3: Based on now Coordinate plane and summer The turbidity data of the plane or one-dimensional coordinate plane is calculated to obtain the turbidity in three-dimensional space C NTU .

[0006] Preferably, in step S1, the turbidity meter can perform scanning measurement based on Cartesian coordinates.

[0007] Preferably, the present invention can be performed by a static sensor now Coordinate plane and summer The turbidity of the coordinate plane is measured in a gridded manner. The present invention can also obtain gridded turbidity data by dynamically driving the sensor to perform plane step-by-step scanning detection.

[0008] In order to better implement the present invention, further, step S3 includes the following steps: Step A1: Based on now The plane turbidity data of the coordinate plane is calculated now Turbidity average on the coordinate plane ; Step A2: Based on summer The plane turbidity data of the coordinate plane is calculated summer Turbidity average on the coordinate plane ; Step A3: Based on steps A1 and A2, calculate the turbidity in three-dimensional space C NTU for: , in: , , in: w xoz for now Turbidity weighting coefficient of the coordinate plane; w yoz for summer Turbidity weighting coefficient of the coordinate plane; for now mean deviation of turbidity in the coordinate plane; for summer Mean deviation of turbidity in the coordinate plane.

[0009] .

[0010] In order to better implement the present invention, further, in the step A1, now Turbidity average on the coordinate plane for: , In the step A2, summer Turbidity average on the coordinate plane for: , in: l for x The number of subdivision steps on the axis; m for y The number of subdivision steps on the axis; n for z The number of subdivision steps on the axis; C ij for now Coordinate plane or summer Turbidity data in the coordinate plane.

[0011] .

[0012] In order to better implement the present invention, further, in step A3, the uncertainty caused by the plane turbidity data measurement is for: .

[0013] .

[0014] In order to better implement the present invention, further, step S3 includes the following steps: Step B1: Based on now Coordinate plane x Dimensional turbidity data, calculation now Turbidity value of the plane C xoz ; Step B2: Based on summer Coordinate plane y Dimensional turbidity data, calculation summer Turbidity value of the plane C yoz ; Step B3: Based on step B1 and step B2, calculate the turbidity in three-dimensional space C NTU for: , in: , , in: w ix for now The coordinate plane i indivual x The weight coefficient of the dimension; w iy for summer The coordinate plane i indivual y The weight coefficient of the dimension; for now The coordinate plane i indivual x Dimensional turbidity average; for summer The coordinate plane i indivual y Dimensional turbidity average; n for z The number of subdivision steps on the axis.

[0015] .

[0016] In order to better implement the present invention, further, in step B3, the uncertainty caused by the single-dimensional turbidity data measurement for: , , , in: for now Turbidity of the coordinate plane C xoz The uncertainty of for summer Turbidity of the coordinate plane C yoz uncertainty.

[0017] .

[0018] In order to better implement the present invention, further, in step S2, multi-band measurement is adopted now Coordinate plane and summer Turbidity data on a coordinate plane; the turbidity measured C MW for: , in: λ r is the wavelength of monochromatic light; α r The wavelength is λ r Weight coefficient of monochromatic light; The wavelength measured for the monochromatic light model is λ r Turbidity of monochromatic light; r It is a monochromatic light type.

[0019] .

[0020] In order to better implement the present invention, further, 550nm and 860nm dual-band measurement is adopted. now Coordinate plane and summer Turbidity data on a coordinate plane; the turbidity measured C DM for: , in: α is the weight coefficient of 860nm light; Measure the turbidity of 860nm light for the monochromatic light model; β 550 nm Light weight coefficient; Measures the turbidity of 550nm light for the monochromatic light model.

[0021] .

[0022] In order to better realize the present invention, further, hexamethylenetetramine C6H 12 N4 and hydrazine sulfate N2H6SO4 were used to prepare standard turbidity solutions with different concentrations. Then, the turbidity values ​​were measured respectively using a monochromatic light 90° scattering measurement model, and the weight coefficients of each measurement band were obtained through matrix calculation.

[0023] The present invention is mainly achieved through the following technical solutions: A three-dimensional turbidity measurement system based on space scanning is based on the above three-dimensional turbidity measurement method based on space 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 plane data processing unit and a single-dimensional data processing unit; The turbidity meter comprises a multi-band light source array and a 90° detector and a 180° detector arranged corresponding to each band light source, wherein the 90° detector and the 180° detector are used to measure the 90° direction light intensity and the transmitted light intensity of the band light source respectively; the turbidity meter is used to calculate the turbidity measured in each band by 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 based on now Coordinate plane and summer The turbidity data of the coordinate plane is used to calculate the turbidity in three-dimensional space. C NTU ; The single-dimensional data processing unit is used to now Coordinate plane and summer Coordinate plane x Dimensions and y Dimensional turbidity data, calculate the turbidity in three-dimensional space C NTU .

[0024] The beneficial effects of the present invention are as follows: The present invention is through the three-dimensional space to be measured now Coordinate plane and summer The turbidity of the coordinate plane is scanned and measured to obtain gridded turbidity data, and the turbidity in three-dimensional space is calculated based on the plane turbidity data or the one-dimensional turbidity data, which effectively improves the accuracy of turbidity measurement, solves the limitation of single-point measurement, and has good practicality.

[0025] The present invention processes 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 reflecting 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 for turbidity measurement in three-dimensional space and having good practicality.

[0026] The present invention is based on dual-band or multi-band scanning to measure the turbidity of the plane, further increasing the accuracy of single-point turbidity data measurement. The present invention improves the traditional 90° scattering method, using 90° scattering and 180° transmitted light intensity (traditionally incident light intensity) for measurement, and does not rely on incident light intensity (light source); it overcomes the problem that traditional sensors need to be corrected - the light source of traditional sensors decays over time and the light source driving current needs to be constantly corrected to achieve the stability of the light source (incident light intensity) and ensure the consistency of the sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] tú1 It is a schematic diagram of the principle of turbidity measurement of the turbidity measuring instrument; tú2 This is a flow chart of the three-dimensional turbidity measurement method based on spatial scanning in Example 1; tú3 This is a flow chart of the three-dimensional turbidity measurement method based on spatial scanning in Example 2; tú4 This is the principle block diagram of the three-dimensional turbidity measurement system based on spatial scanning. DETAILED DESCRIPTION

[0028] Embodiment 1: A three-dimensional turbidity measurement method based on space scanning, which establishes a three-dimensional xyz Coordinate system, scan and measure separately now Coordinate plane and summer Coordinate plane and obtain gridded turbidity data; based on now Coordinate plane and summer The turbidity data of the coordinate plane is calculated to obtain the turbidity in three-dimensional space C NTU .

[0029] Preferably, if tú2 As shown, the specific steps include: Step 1: Data Scanning: Turbidity scanning adopts step-by-step plane scanning. The plane scanning process first x The process of axis motion scanning is then y The axis movement scans the process and then moves z axis, and then repeat the plane sweep.

[0030] (1) Obtained through spatial scanning now Coordinate plane scan data:

[0031] in: l for x The number of subdivision steps on the axis; n for z The number of subdivision steps on the axis.

[0032] (2) Obtained through spatial scanning summer Coordinate plane scan data:

[0033] in: m for y The number of subdivision steps on the axis; n for z The number of subdivision steps on the axis.

[0034] Step 2: Calculate turbidity in three dimensions C NTU : Use the plane calculation method to quickly calculate the turbidity value: use the plane data to calculate the arithmetic mean, standard deviation, average deviation, weighting coefficient and turbidity in three-dimensional space in turn C NTU .

[0035] Step A1: Based on now The plane turbidity data of the coordinate plane is calculated now Turbidity average on the coordinate plane : 1) Calculate the turbidity at now Arithmetic mean of coordinate plane scan data

[0036] in: Turbidity now The arithmetic mean of the coordinate plane scan data; C ij For process operation data, C ij∈ C nl ; work The process data has no practical meaning; l for x The number of subdivision steps on the axis; n for z The number of subdivision steps on the axis.

[0037] 2) Calculate the standard deviation

[0038] in: Turbidity nowStandard deviation of the coordinate plane; Turbidity now The arithmetic mean of the coordinate plane scan data; C ij For process operation data, C ij∈ C nl ; work The process data has no practical meaning; l is the number of subdivision steps on the x-axis; n is the number of subdivision steps on the z-axis; 3) Calculate the average deviation

[0039] in: Turbidity now Standard deviation of the coordinate plane; Turbidity now Mean deviation of the coordinate plane; l is the number of subdivision steps on the x-axis; n is the number of subdivision steps on the z-axis.

[0040] Step A2: Based on summer The plane turbidity data of the coordinate plane is calculated summer Turbidity average on the coordinate plane ; 1) Calculate the turbidity at summer Arithmetic mean of coordinate plane scan data

[0041] in: Turbidity summer The arithmetic mean of the coordinate plane scan data; C ij For process operation data, C ij∈ C mn ; work Process data has no practical meaning; m is the number of subdivision steps on the y-axis; n is the number of subdivision steps on the z-axis; 2) Calculate the standard deviation

[0042] in: Turbidity summer Standard deviation of the coordinate plane; Turbidity now The arithmetic mean of the coordinate plane scan data; C ij For process operation data, C ij∈ C nl ; work The process data has no practical meaning; 3) Calculate the average deviation

[0043] in: Turbidity summer Standard deviation of the coordinate plane; Turbidity summer Mean deviation of the coordinate plane; 4) Calculation method of weighting coefficient:

[0044]

[0045] Turbidity now Mean deviation of the coordinate plane; Turbidity summer Mean deviation of the coordinate plane; w xoz Turbidity now Weighting coefficients of the coordinate plane; w yoz Turbidity summer Weighting coefficients of the coordinate plane; Step A3: Based on steps A1 and A2, calculate the turbidity in three-dimensional space C NTU for:

[0046] Turbidity now The arithmetic mean of the coordinate plane scan data; Turbidity now The arithmetic mean of the coordinate plane scan data; Step 3: Weighted average uncertainty assessment:

[0047] in: Uncertainty caused by measurement (Class A).

[0048] The present invention is through the three-dimensional space to be measured now Coordinate plane and summer The turbidity of the coordinate plane is scanned and measured to obtain gridded turbidity data, and based on the adjacent now Coordinate plane and summer The turbidity calculation of the coordinate plane can obtain the turbidity in three-dimensional space, which effectively improves the accuracy of turbidity measurement and solves the limitation of single-point measurement. now Coordinate plane and summer The turbidity data on the coordinate plane can be quickly calculated to obtain the turbidity in three-dimensional space that reflects the overall measurement situation, which has good practicality.

[0049] Embodiment 2: A three-dimensional turbidity measurement method based on space scanning, which establishes a three-dimensional xyz Coordinate system, scan and measure separately now Coordinate plane and summer Coordinate plane and obtain gridded turbidity data; based on now Coordinate plane and summer The turbidity data of the single-dimensional coordinate plane is calculated to obtain the turbidity of the three-dimensional space C NTU .

[0050] Preferably, if tú3 As shown, the specific steps include: Step 1: Data scanning is the same as that described in Example 1, so it will not be repeated here.

[0051] Step 2: Use the one-dimensional calculation method to accurately calculate the turbidity value C NTU :use x axis, y The data of the axis are subdivided and then calculated overall. Specifically, the single-dimensional data of each plane is calculated based on the single-dimensional calculation model - the arithmetic mean, standard deviation, average deviation, and weighting coefficient are calculated in turn; finally, the different single-dimensional data are integrated to obtain the turbidity of the three-dimensional space C NTU .

[0052] The single-dimensional calculation model is: a1. Calculate the arithmetic mean

[0053] in: g is the number of subdivision steps in a single dimension, g ∈{ l m}; It is the arithmetic mean obtained from a single scan in a single dimension; C i Calculates data for the subdivision measurement process of single-dimensional scanning, C i ∈ C nl ∪ C nm ; i The process data has no practical meaning.

[0054] a2. Calculate standard deviation

[0055] in: is the standard deviation of turbidity in a single dimension.

[0056] a3. Calculate the average deviation

[0057] in: is the average deviation of turbidity in a single dimension.

[0058] a4. Single dimension weighting coefficient

[0059] Preferably, the specific steps of the one-dimensional calculation method are as follows: Step B1: Based on now Coordinate plane x Dimensional turbidity data, calculation now Turbidity value of the plane C xoz ; (1) Through the single-dimensional calculation model, we can obtain now Dimensional data of the coordinate plane: The arithmetic mean is:

[0060] The standard deviation is:

[0061] The weighting coefficient is:

[0062] (2) The unit dimension calculation model is used to obtain summer Coordinate plane y Dimensional data: The arithmetic mean is

[0063] The standard deviation is

[0064] Weighting coefficient

[0065] (3) Calculation now Coordinate plane scanned data:

[0066] in: C xoz for now Turbidity calculated on the coordinate plane; w ix for now Single-dimensional weight coefficient of the coordinate plane, w ix ∈w nx ; for now The average value of the single-dimensional turbidity scan in the coordinate plane, ; 2) Uncertainty data is:

[0067] in: for now Turbidity calculated on the coordinate plane C xoz The uncertainty of w ix for now Single dimension weight coefficient of coordinate plane w ix ∈w nx ; Step B2: Based on summer Coordinate plane y Dimensional turbidity data, calculation summer Turbidity value of the plane C yoz ;

[0068] in: w iy for summer Single-dimensional weight coefficient of the coordinate plane, w iy ∈w ny ; for summer The average value of the single-dimensional turbidity scan in the coordinate plane, ; The uncertainty data is:

[0069] in: for summer Turbidity of the coordinate plane C yoz The uncertainty of Step B3: Based on step B1 and step B2, calculate the turbidity in three-dimensional space C NTU for:

[0070] in: C xoz for now Turbidity values ​​on the coordinate plane; for summer Turbidity calculated on the coordinate plane; Step 3: The uncertainty caused by the measurement is: .

[0071] The present invention is through the three-dimensional space to be measured now Coordinate plane and summer The turbidity of the coordinate plane is scanned and measured to obtain gridded turbidity data, and based on the adjacent now Coordinate plane and summer The surface turbidity calculation of the coordinate plane obtains the turbidity in three-dimensional space, which effectively improves the accuracy of turbidity measurement and solves the limitation of single-point measurement. 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 for turbidity measurement in three-dimensional space and having good practicality.

[0072] Embodiment 3: This embodiment is optimized based on embodiment 1 or 2. tú1 As shown, turbidity measurement is based on light scattering theory and uses 550nm (visible light band) and 860nm (near infrared band) dual band measurement. now Coordinate plane and summerTurbidity data on the coordinate plane. Visible light band measurement is sensitive to dissolved organic matter and is easily interfered by chromaticity, 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 of chromaticity and turbidity. The specific calculation formula is as follows:

[0073] in: C DM The turbidity of the solution is measured by dual-band scanning; 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.

[0074] Preferably, the weight coefficient is measured as follows: 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:

[0075] The turbidity values ​​measured by the monochromatic light 90° scattering measurement model are:

[0076] Establish weight coefficients:

[0077] The weight value obtained by matrix operation is:

[0078] in: α is the weight coefficient of 860nm light; β is the weight coefficient of 550nm light; n is the number of solutions with different concentrations, n>2 ; w is the weight coefficient matrix; x is the matrix of measured solution turbidity values; y is the turbidity value matrix of standard substances.

[0079] The other parts of this embodiment are the same as those of Embodiment 1 or Embodiment 2, and thus will not be described in detail.

[0080] Embodiment 4: This embodiment is optimized based on embodiment 1 or 2, and adopts multi-band measurement now Coordinate plane and summer Turbidity data of the coordinate plane. The specific calculation formula is as follows:

[0081] in: CMW The turbidity of the solution is measured by multi-band scanning; λ r is the wavelength of monochromatic light; α r The wavelength is λ r Weight coefficient of monochromatic light; The wavelength measured for the monochromatic light model is λ r Turbidity of monochromatic light; r It is a monochromatic light type; Preferably, the weight coefficient is measured as follows: 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:

[0082] The turbidity values ​​measured by the monochromatic light 90° scattering measurement model are:

[0083] Establish weight coefficients:

[0084] The weight value obtained by matrix operation is:

[0085] n is the number of solutions with different concentrations, and n>m ; r It is a monochromatic light type; w is the weight coefficient matrix; λ r is the wavelength of monochromatic light; x is the matrix of turbidity values ​​of the measured solution; y is the turbidity value matrix of standard substances.

[0086] The other parts of this embodiment are the same as those of Embodiment 1 or Embodiment 2, and thus will not be described in detail.

[0087] Embodiment 5: A three-dimensional turbidity measurement system based on spatial scanning, such as tú4 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.

[0088] The scanning data acquisition unit is used to collect gridded turbidity data of three-dimensional scanning; The plane data processing unit is used based on now Coordinate plane and summer The turbidity data of the coordinate plane is used to calculate the turbidity in three-dimensional space. C NTU ; The single-dimensional data processing unit is used to now Coordinate plane and summer Coordinate plane x Dimensions and y Dimensional turbidity data, calculate the turbidity in three-dimensional space C NTU .

[0089] The turbidity meter includes a light source module and a 90° detector and a 180° detector, wherein the 90° detector and the 180° detector are used to measure the 90° direction light intensity and the transmitted light intensity of the band light source respectively. The turbidity meter is used to calculate the turbidity measured in each band using the 90° scattered light and the 180° transmitted light intensity.

[0090] like tú1 As shown, the measurement model of the turbidity meter is:

[0091] in: C is the solution turbidity; k NTU is the turbidity instrument correction factor; I S The light intensity is at 90°. I t is the intensity of transmitted light.

[0092] 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 of light sources. 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.

[0093] The present invention is based on dual-band or multi-band scanning to measure the turbidity of the plane, further increasing the accuracy of single-point turbidity data measurement. The present invention improves the traditional 90° scattering method, using 90° scattering and 180° transmitted light intensity (traditionally incident light intensity) for measurement, and does not rely on incident light intensity (light source); it overcomes the problem that traditional sensors need to be corrected - the light source of traditional sensors decays over time and the light source driving current needs to be constantly corrected to achieve the stability of the light source (incident light intensity) and ensure the consistency of the sensor.

[0094] 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 protection scope 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: Create a three-dimensional space in the three-dimensional space to be tested xyz Coordinate system; Step S2: Scan and measure separately xoz Coordinate plane and yoz Coordinate plane, and obtain gridded turbidity data; Step S3: Based on xoz Coordinate plane and yoz The turbidity data of the plane or one-dimensional coordinate plane is calculated to obtain the turbidity in three-dimensional space C NTU .

2. A three-dimensional turbidity measurement method based on spatial scanning according to claim 1, characterized in that: The step S3 comprises the following steps: Step A1: Based on xoz The plane turbidity data of the coordinate plane is calculated xoz Turbidity average on the coordinate plane ; Step A2: Based on yoz The plane turbidity data of the coordinate plane is calculated yoz Turbidity average on the coordinate plane ; Step A3: Based on steps A1 and A2, calculate the turbidity in three-dimensional space C NTU for: ， in: , ， in: w xoz for xoz Turbidity weighting coefficient of the coordinate plane; w yoz for yoz Turbidity weighting coefficient of the coordinate plane; for xoz mean deviation of turbidity in the coordinate plane; for yoz Mean deviation of turbidity in the coordinate plane.

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

4. The three-dimensional turbidity measurement method based on spatial scanning according to claim 2 is characterized in that: In step A3, the uncertainty caused by the plane turbidity data measurement for: 。 5. The three-dimensional turbidity measurement method based on spatial scanning according to claim 1, characterized in that: The step S3 comprises the following steps: Step B1: Based on xoz Coordinate plane x Dimensional turbidity data, calculation xoz Turbidity value of the plane C xoz ; Step B2: Based on yoz Coordinate plane y Dimensional turbidity data, calculation yoz Turbidity value of the plane C yoz ; Step B3: Based on step B1 and step B2, calculate the turbidity in three-dimensional space C NTU for: ， in: , ， in: w ix for xoz The coordinate plane i indivual x The weight coefficient of the dimension; w iy for yoz The coordinate plane i indivual y The weight coefficient of the dimension; for xoz The coordinate plane i indivual x Dimensional turbidity average; for yoz The coordinate plane i indivual y Dimensional turbidity average; n for z The number of subdivision steps on the axis.

6. A three-dimensional turbidity measurement method based on spatial scanning according to claim 5, characterized in that: In step B3, the uncertainty caused by the single-dimensional turbidity data measurement is for: ， ， ， in: for xoz Turbidity of the coordinate plane C xoz The uncertainty of for yoz Turbidity of the coordinate plane C yoz uncertainty.

7. A three-dimensional turbidity measurement method based on spatial scanning according to any one of claims 1 to 6, characterized in that: In step S2, multi-band measurement is used xoz Coordinate plane and yoz Turbidity data on a coordinate plane; the turbidity measured C MW for: ， in: λ r is the wavelength of monochromatic light; α r The wavelength is λ r Weight coefficient of monochromatic light; The wavelength measured for the monochromatic light model is λ r Turbidity of monochromatic light; r It is a monochromatic light type.

8. The three-dimensional turbidity measurement method based on spatial scanning according to claim 7, characterized in that: Using 550nm and 860nm dual band measurement xoz Coordinate plane and yoz Turbidity data on a coordinate plane; the turbidity measured C DM for: ， in: α is the weight coefficient of 860nm light; Measure the turbidity of 860nm light for the monochromatic light model; β 550 nm Light weight coefficient; Measures the turbidity of 550nm light for the monochromatic light model.

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

10. 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 9, characterized in that: It includes a turbidity measuring instrument and a data processing module, wherein the data processing module includes a multi-band turbidity measuring unit, a scanning data acquisition unit, a plane data processing unit and a single-dimensional data processing unit; The turbidity meter comprises a multi-band light source array and a 90° detector and a 180° detector arranged corresponding to each band light source, wherein the 90° detector and the 180° detector are used to measure the 90° direction light intensity and the transmitted light intensity of the band light source respectively; the turbidity meter is used to calculate the turbidity measured in each band by 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 based on xoz Coordinate plane and yoz The turbidity data of the coordinate plane is used to calculate the turbidity in three-dimensional space. C NTU ; The single-dimensional data processing unit is used to xoz Coordinate plane and yoz Coordinate plane x Dimensions and y Dimensional turbidity data, calculate the turbidity in three-dimensional space C NTU .

Images