CN115078191A - Method and system for measuring granularity of high-concentration slurry by utilizing ultrasonic - Google Patents
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- G01N15/00—Investigating characteristics of particles; Investigating permeability, pore-volume or surface-area of porous materials
- G01N15/02—Investigating particle size or size distribution
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- G—PHYSICS
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- G—PHYSICS
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- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
- G01N29/44—Processing the detected response signal, e.g. electronic circuits specially adapted therefor
- G01N29/4409—Processing the detected response signal, e.g. electronic circuits specially adapted therefor by comparison
- G01N29/4418—Processing the detected response signal, e.g. electronic circuits specially adapted therefor by comparison with a model, e.g. best-fit, regression analysis
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2291/00—Indexing codes associated with group G01N29/00
- G01N2291/01—Indexing codes associated with the measuring variable
- G01N2291/015—Attenuation, scattering
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Abstract
The invention provides a method and a system for measuring the granularity of high-concentration slurry by utilizing ultrasonic. The method of the invention comprises the following steps: s1: placing an ultrasonic probe in the slurry to be detected, and acquiring an ultrasonic reflection signal of the slurry to be detected; s2: processing the ultrasonic reflection signal by using a pulse echo method to obtain an ultrasonic attenuation spectrum; s3: and (4) utilizing an ORT algorithm to carry out inversion on the ultrasonic attenuation spectrum to obtain the granularity information of the slurry to be measured. The method and the system have the advantages of high accuracy, good stability, strong adaptability and the like, and are suitable for measuring the granularity of the high-concentration slurry under various working conditions.
Description
Technical Field
The invention relates to the technical field of particle size measurement, in particular to a method and a system for measuring the particle size of high-concentration slurry by utilizing ultrasound.
Background
A particulate two-phase flow refers to a two-phase flow in which the discrete phase is particulate matter. With the development of particle-related fields such as power engineering, material preparation, equipment manufacturing and the like, particle size measurement in particle multiphase fluids is receiving wide attention. For example, coal fired power plants pass limestone slurry as SO 2 The finer the granularity in the limestone slurry is, the larger the contact area of the equivalent limestone slurry in the absorption tower during chemical reaction is, the more sufficient the reaction is, the higher the desulfurization efficiency is, and the better the quality of the generated gypsum is; however, the fine particles in the limestone slurry cause the mill to over grind, which in turn increases the energy consumption of the plant operation. Therefore, it is necessary to set the particle size of the limestone slurry within a reasonable range, and the measurement of the particle size of the limestone slurry becomes the most important link.
The existing particle size measuring methods include a screening method, a sedimentation method, an electric induction method, a light scattering method and the like. With the continuous improvement of the requirements of measurement accuracy and measurement speed and the rapid expansion of the measurement range and application field, the traditional measurement method is gradually eliminated. The ultrasonic measurement has the advantages of strong penetrability, wide frequency band, applicability to high-concentration online measurement which is difficult to penetrate by an optical method and the like, but has the problems of limited application range, low accuracy and stability and the like when being used for measuring the particle size of high-concentration slurry.
In view of this, the invention is particularly proposed.
Disclosure of Invention
The invention aims to provide a method and a system for measuring the granularity of high-concentration slurry by utilizing ultrasonic, and the method and the system have the advantages of high accuracy, good stability, strong adaptability and the like.
The invention provides a method for measuring the granularity of high-concentration slurry by utilizing ultrasonic, which comprises the following steps:
s1: placing an ultrasonic probe in the serous fluid to be detected (also called as a sample), and collecting an ultrasonic reflection signal of the serous fluid to be detected;
s2: processing the ultrasonic reflection signal by using a pulse echo method to obtain an ultrasonic attenuation spectrum;
s3: and (3) utilizing an ORT (optimal-Regularization-Technique) algorithm to invert the ultrasonic attenuation spectrum to obtain the granularity information of the slurry to be detected.
In the present invention, the ultrasonic probe (also referred to as a transmitting-receiving probe) is mainly used for transmitting an ultrasonic signal and receiving an ultrasonic reflection signal, and the structure thereof is not strictly limited, and an ultrasonic probe conventional in the art may be used.
In an embodiment, the ultrasonic probe comprises a housing, an ultrasonic transducer and a reflection block, the ultrasonic transducer is arranged at the front end of the housing opposite to the reflection block, a buffer block is arranged on one side of the ultrasonic transducer facing the reflection block, a measurement area is formed between the buffer block and the reflection block, and the distance between the buffer block and the reflection block (namely the width of the measurement area) is adjustable. The whole ultrasonic probe can be in a rod shape, so that the ultrasonic probe can be conveniently placed in the slurry to be measured at different positions (such as a storage tank, the interior of a pipeline and the like). The ultrasonic probe with the structure has good portability, can adjust the width of a measuring area, has long transmission distance of ultrasonic waves, and can contain richer granularity information, so that the measuring result is more accurate.
More specifically, the housing may be a hollow tubular housing, the ultrasonic transducer is mounted at a front end of the hollow tubular housing, and the reflection block is slidably disposed at the front end of the hollow tubular housing through the stretchable adjustment structure and disposed opposite to the ultrasonic transducer. The specific arrangement of the stretchable adjusting structure is not strictly limited, as long as the reflective block can be driven to slide relative to the hollow tubular shell so as to adjust the distance between the reflective block and the buffer block, and the conventional structure in the field can be adopted.
Further, the stretchable adjusting structure may include a sliding connector, the reflection block is fixed at one end of the sliding connector, the other end of the sliding connector is slidably disposed in the hollow tubular housing, and a plurality of positioning bolts for fixing the sliding connector are disposed on the hollow tubular housing at intervals along the length direction. The structure of the sliding connecting piece is not strictly limited, for example, the sliding connecting piece can be arranged into a shell shape, and the sliding connecting piece and the hollow tubular shell form a double-layer shell structure, so that the sliding of the sliding connecting piece is convenient to realize; the distance between adjacent positioning bolts is not strictly limited, and can be determined according to actual requirements. In addition, a protective layer may be provided on the outside of the ultrasonic transducer to protect the ultrasonic transducer.
The distance between the ultrasonic probe buffer block and the reflection block is not strictly limited, and can be reasonably set according to actual requirements, for example, the distance can be set to be 5mm-20 mm. At the moment, the ultrasonic probe can be used for measuring various working conditions such as pipe diameters and storage tanks with different sizes, particles with different sizes and slurry with different concentrations, and has strong adaptability and wider application range.
Further, the ultrasound probe may have a focusing member for focusing the ultrasound; the structure and arrangement of the focusing member are not strictly limited as long as they can focus the ultrasound, and a conventional ultrasound focusing structure in the art may be employed. For example, the surface of the buffer block contacting the slurry to be measured can be designed to be a concave surface, and the concave surface is used for focusing ultrasonic energy in advance, so that the unfavorable conditions that ultrasonic waves cannot penetrate through the slurry to be measured with high concentration due to low energy and the like are avoided.
In step S1, the ultrasonic reflection signal includes a primary echo signalA 1 And secondary echo signalA 2 . Specifically, as shown in FIG. 2, the ultrasonic signal emitted by the ultrasonic probeA 0 When passing through the interface of the buffer block and the sample, the buffer block and the sampleThe samples have impedance difference to generate reflection, and the reflected signals are received by the buffer block to be primary echo signalsA 1 (ii) a Meanwhile, the transmitted wave continuously passes through the sample and is correspondingly reflected on the interface between the sample and the reflecting block, and the reflected signal is received by the buffer block to be a secondary echo signalA 2 。
In step S2, the principle of measuring the particle size by the pulse echo method is as follows:
the pulse echo method measures the primary echo signalA 1 And secondary echo signalA 2 The two are distinguished in thatA 2 Has undergone the sample layerA 1 Only within the buffer block. The method comprises the steps of analyzing the frequency spectrum of a time domain signal by adopting an ultrasonic time domain signal through a Fast Fourier Transform (FFT) technology, and calculating corresponding multi-frequency components according to the amplitude of corresponding frequencies, so that a corresponding ultrasonic attenuation spectrum is obtained through amplitude spectrum analysis.
The ultrasonic attenuation coefficient of the two-phase medium in the measurement area is expressed as:
wherein:α s the attenuation coefficient of the slurry to be measured;A 1 is a primary echo signal;A 2 is a secondary echo signal;R s the reflection coefficient between the ultrasonic probe buffer block and the slurry to be detected is obtained;l 2 the width of the zone is measured for the ultrasonic probe. In the present invention, in the case of the present invention,l 2 the concentration of the slurry to be measured is continuously adjustable.
Further, air is used as a reference calibration material to simplify the calculation. When no sample is contained in the sample cell (i.e., the measurement region), a set of reflected signals can be measuredA a The total reflection at the interface occurs because the air impedance is extremely small relative to the impedance of the buffer block (generally, organic glass), and the ultrasonic attenuation coefficient of the obtained sample is as follows:
wherein:A a is the reflected signal obtained when air is used as a reference standard.
In step S3, the ORT algorithm assumes no assumption in advance about the particle size distribution of the particle system of the slurry to be measured, and obtains the particle size distribution by solving a discrete equation set. The particle size distribution solving problem can be classified as the solution of a linear equation system, and under the condition of multiple frequencies, a formula is dispersed and converted into the following linear equation form:
wherein:Ais a matrix of attenuation coefficients;Fdiscretizing volume frequency distribution for the slurry particles to be detected;Gis a vector consisting of the attenuation of ultrasound at different frequencies. Attenuation coefficient matrixACan be obtained in a conventional manner according to the ECAH model.
A Twyy and ORT solving algorithm can be introduced into an actual particle solving problem, a fairing constraint condition is added, a regularization factor gamma and a fairing matrix H are introduced, and the expression is as follows:
wherein:A T is composed ofAThe transposed matrix of (2);γis the weight of the fairing factor.γThe selection of (A) is determined according to the specific application scenario ifγToo small an amount of solution will appear, ifγToo large results in too smooth a distribution of particles that does not distinguish between the true peak positions,γthe value of (A) is usually in the range of 0.001 to 0.1.
In addition, in order to inhibit the influence of random noise in experimental data, quadratic function curve fitting can be carried out on ultrasonic attenuation spectrum data, and a correlation coefficient R is obtained 2 The value of (c). R is to be 2 Is set in the interval of 0.999-0.9 (i.e. values greater than 0.999 are all recorded as 0.999; values less than 0.999)Values of 0.9 are all noted as 0.9), and may be inγAnd R 2 Establishing a value corresponding relation between the two groups; specifically, R 2 The larger the size of the tube is,γthe smaller the value, e.g. R 2 When the content of the organic acid is 0.999,γthe value can be 0.001; r 2 When the content of the organic acid is 0.9,γthe value may be 0.1.
The fairing matrix H is defined as:
further, a non-negative least square problem is adopted for solving, and meanwhile, consideration is given toFThe physical meaning of (particle size distribution should be non-negative), i.e.:
wherein:Fa more than or equal to 0 is a non-negative number solution.
The invention also provides a system for measuring the particle size of the high-concentration slurry by using the ultrasonic wave (referred to as an ultrasonic measurement system for short), which comprises an ultrasonic probe, an ultrasonic pulse transmitting and receiving module, a signal amplification and acquisition module and a data processing module, wherein the input end and the output end of the ultrasonic pulse transmitting and receiving module are respectively connected with the ultrasonic probe and the signal amplification and acquisition module, the output end of the signal amplification and acquisition module is connected with the data processing module, the data processing module comprises a first processing module and a second processing module, the first processing module processes the ultrasonic reflection signal acquired by the signal amplification and acquisition module by using a pulse echo method to obtain an ultrasonic attenuation spectrum, and the second processing module carries out inversion on the ultrasonic attenuation spectrum by using an ORT algorithm to obtain the particle size information of the slurry to be measured.
The implementation of the invention has at least the following advantages:
1. the ultrasonic probe adopted by the invention has the advantages of simple structure, good portability and convenient installation, and can realize real-time online monitoring of the granularity of the slurry at different positions (such as a storage tank, the inside of a pipeline and the like);
2. the ultrasonic probe adopted by the invention can adjust the width of the measuring area, the transmission distance of the ultrasonic wave is long, the propagation acoustic path is 2 times of the distance between the buffer block and the reflecting block, and the ultrasonic reflection signal contains richer particle size information, so that the measuring result is more accurate;
3. the method can measure various working conditions such as different pipe diameters, different storage tanks, different-size particles, different-concentration slurry and the like, and has strong adaptability and wide application range;
4. the ultrasonic energy can be focused, so that the unfavorable conditions that the ultrasonic cannot penetrate through high-concentration slurry to be measured due to low energy, the ultrasonic cannot be measured and the like are avoided;
5. the invention obtains the ultrasonic attenuation spectrum by using the pulse echo method, obtains the information of the granularity of the slurry to be measured by using the ORT algorithm for inversion, has high measurement accuracy and good measurement stability, and is particularly suitable for measuring the granularity of the high-concentration slurry in multiphase flow.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.
FIG. 1 is a schematic structural diagram of an ultrasound probe according to an embodiment of the present invention;
FIG. 2 is a schematic view of the ultrasonic propagation path inside the measurement zone according to the present invention;
FIG. 3 is a schematic structural diagram of an ultrasonic measurement system according to an embodiment of the present invention;
FIG. 4 is a graph comparing the experimental attenuation spectrum with the theoretical attenuation spectrum of example 1 of the present invention;
FIG. 5 is a fitting curve obtained by performing quadratic function curve fitting on ultrasonic attenuation spectrum data in example 1 of the present invention;
FIG. 6 is a particle size distribution obtained in example 1 of the present invention;
FIG. 7 is an image obtained by the image method measurement according to example 1 of the present invention;
FIG. 8 is a graph showing a comparison of particle size distributions obtained by the ultrasonic method and the image method in example 1 of the present invention;
FIG. 9 shows the particle size distributions of different concentrations of silica sand in example 2 of the present invention;
FIG. 10 is a graph showing a particle size distribution of a limestone slurry according to comparative example 1 of the present invention using a DFP algorithm;
FIG. 11 is a graph of the particle size distribution of a limestone slurry of comparative example 1 of the present invention using the NNLS algorithm.
Description of reference numerals:
1: a housing; 2: a protective layer; 3: a measurement zone; 4: a reflection block; 5: an ultrasonic transducer; 6: a stretch adjustable structure;
10: an ultrasonic pulse transmitting and receiving module; 11: an ultrasonic probe; 12: a sample cell; 13: a signal amplification and acquisition module; 14: and a data processing module.
Detailed Description
It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the disclosure. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.
It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms also include the plural forms unless the context clearly dictates otherwise, and further, it is understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of the stated features, steps, operations, devices, components, and/or combinations thereof.
The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments, and it should be understood that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1
In this example, the particle size distribution of a high-concentration limestone slurry (about 40% by mass) of a certain power plant is measured.
The structure of the ultrasonic probe is shown in fig. 1. The ultrasonic probe comprises a shell 1, a reflecting block 4 and an ultrasonic transducer 5, wherein the shell 1 is a hollow tubular shell, the reflecting block 4 and the ultrasonic transducer 5 are arranged at the front end of the hollow tubular shell, a buffer block (not shown in figure 1) is arranged on one side, facing the reflecting block 4, of the ultrasonic transducer 5, a measuring area 3 is formed between the buffer block and the reflecting block 4, the distance between the buffer block and the reflecting block 4 is adjustable within the range of 5mm-20mm, a protective layer 2 is arranged outside the ultrasonic transducer 5, and the reflecting block 4 is arranged on the hollow tubular shell in a sliding mode through a stretchable adjusting structure 6 so that the distance between the reflecting block 4 and the buffer block can be adjusted.
The propagation path of the ultrasonic wave inside the measurement region is shown in fig. 2. Ultrasonic signals emitted by ultrasonic probeA 0 When the reflected signal passes through the interface of the buffer block and the sample, the reflected signal is a primary echo signal after being received by the buffer block due to the reflection caused by the impedance difference between the buffer block and the sampleA 1 (ii) a Meanwhile, the transmitted wave continuously passes through the sample and is correspondingly reflected on the interface between the sample and the reflecting block, and the reflected signal is received by the buffer block to be a secondary echo signalA 2 。
The structure of the ultrasonic measurement system is shown in fig. 3. The ultrasonic measurement system comprises an ultrasonic pulse transmitting and receiving module 10, the ultrasonic probe 11, a signal amplification and acquisition module 13 and a data processing module 14, wherein the input end and the output end of the ultrasonic pulse transmitting and receiving module 10 are respectively connected with the ultrasonic probe 11 and the signal amplification and acquisition module 13, the output end of the signal amplification and acquisition module 13 is connected with the data processing module 14, the data processing module 14 comprises a first processing module and a second processing module, the first processing module processes ultrasonic reflection signals acquired by the signal amplification and acquisition module 13 by using a pulse echo method to obtain an ultrasonic attenuation spectrum, and the second processing module performs inversion on the ultrasonic attenuation spectrum by using an ORT algorithm to obtain the granularity information of the slurry to be measured.
The measurement experiment of the embodiment is carried out in a circular tube (i.e. the sample cell 12) with the inner diameter of 30mm, an underwater ultrasonic transducer with the central frequency of 5MHz is used, the sampling frequency is 250MHz, and the sound path of the measurement area 3 is adjusted to be 12.5 mm; the measurement steps are as follows:
1. measurement:
after the ultrasonic pulse transmitting and receiving module 10 and the ultrasonic probe 11 are connected, the ultrasonic probe 11 is inserted into the high-concentration limestone slurry, and the ultrasonic signal emitted by the ultrasonic transducer 5A 0 When the reflected signal passes through the interface of the buffer block and the sample, the reflected signal is a primary echo signal after being received by the buffer block due to the reflection caused by the impedance difference between the buffer block and the sampleA 1 (ii) a At the same time, the transmitted wave continues to pass through the sample and is reflected at the interface between the sample and the reflector block 4 to form a secondary echo signalA 2 . The signal amplification and acquisition module 13 acquires a primary echo signalA 1 And secondary echo signalA 2 And transmitted to the data processing module 14 for data processing.
2. Obtaining an ultrasonic attenuation spectrum
The first processing module of the data processing module 14 uses the pulse echo method to process the primary echo signalA 1 And secondary echo signalA 2 And (6) processing.
Specifically, an ultrasonic attenuation spectrum is obtained by Fast Fourier Transform (FFT) using an ultrasonic time domain signal. The sample attenuation coefficient is expressed as:
wherein:α s the attenuation coefficient of the slurry to be measured;A 1 is a primary echo signal;A 2 is a secondary echo signal;R s the reflection coefficient between the ultrasonic probe buffer block and the slurry to be detected is obtained;l 2 the width of the zone is measured for the ultrasound probe.
Using air as reference calibration material to simplifyAnd (4) calculating. When no sample is contained in the sample cell, a set of reflected signals can be measuredA a The total reflection at the interface occurs because the air impedance is extremely small relative to the impedance of the buffer block (generally, organic glass), and the ultrasonic attenuation coefficient of the obtained sample is as follows:
wherein:A a is the reflected signal obtained when air is used as a reference standard.
The experimental attenuation spectra obtained are shown in fig. 4; the results in FIG. 4 show that: the experimental attenuation spectrum obtained in this example is relatively consistent with the theoretical attenuation spectrum, indicating the feasibility of the ultrasonic measurement method described above.
3. Inversion
The second processing module of the data processing module 14 inverts the ultrasonic attenuation spectrum by using the ORT algorithm, the ORT algorithm does not make any assumption on the particle size distribution of the particle system of the slurry to be measured in advance, and the particle size distribution is obtained by solving a discrete equation set. The particle size distribution solving problem can be classified as the solution of a linear equation system, and under the condition of multiple frequencies, a formula is dispersed and converted into the following linear equation form:
wherein:Ais a matrix of attenuation coefficients;Fdiscretizing volume frequency distribution for the slurry particles to be detected;Gis a vector consisting of the attenuation of ultrasound at different frequencies. Attenuation coefficient matrixAObtained according to the ECAH model.
A Twyy and ORT solving algorithm can be introduced into an actual particle solving problem, a fairing constraint condition is added, a regularization factor gamma and a fairing matrix H are introduced, and the expression is as follows:
wherein:A T is composed ofAThe transposed matrix of (2);γis the weight of the fairing factor.
Performing quadratic function curve fitting on the ultrasonic attenuation spectrum data obtained in the step 2, wherein the fitting curve is shown in figure 5; obtaining a correlation coefficient R according to the fitting curve 2 Value of (A), R 2 Is 0.988, and is thus determinedγThe value is 0.012.
The fairing matrix H is defined as:
further, a non-negative least squares problem is used for solving, while taking into account the physical significance of F (particle size distribution should be non-negative), i.e.:
wherein:Fa more than or equal to 0 is a non-negative number solution.
The ORT inversion is carried out on the ultrasonic attenuation spectrum to obtain the particle size distribution, and the result is shown in figure 6.
The high-concentration limestone slurry of the embodiment was sampled and analyzed by an image method (see fig. 7); the results of the ultrasound method and the image method are compared and shown in fig. 8.
The results in FIG. 8 show that: the particle size distribution obtained by the ultrasonic method and the traditional image method is basically consistent, and the deviation of the median diameter obtained by the ultrasonic method and the traditional image method is less than 5 percent, which shows that the ultrasonic measurement method has high accuracy.
Example 2
In this embodiment, the particle sizes of the quartz sand with different volume concentrations in the water tank are measured, and the volume concentrations of the quartz sand are respectively 3%, 6% and 9% (different volume concentrations are prepared by using the same quartz sand); the sound path of the measurement zone was adjusted to 20 mm.
The measurement procedure was substantially the same as in example 1,γthe value was 0.002, and the ultrasonic measurement results are shown in FIG. 9. The results in FIG. 9 show that: when the measurement is carried out under different concentrations, the measurement result of the granularity of the quartz sand is stableTherefore, the stability of the ultrasonic measurement method of the invention is good.
Comparative example 1
The particle size distribution measurement was performed on the high concentration limestone slurry of example 1.
The method was substantially the same as in example 1, except that the DFP algorithm (Davidon-Fletcher-Powell method) was used for inversion in step 3.
The DFP algorithm of this comparative example is as follows:
and (3) giving an initial point by an iteration method, solving the next search direction according to the correction matrix and the gradient, solving the step length by the Armijo search criterion, recalculating a new initial point, and outputting the point value which is an approximate optimal solution if the gradient of the new point is small enough.
The measurement results are shown in FIG. 10. The results in FIG. 10 show that: when the DFP algorithm of the comparative example is adopted to invert the ultrasonic attenuation spectrum obtained in the example 1, the difference between the measurement result and the image method is large due to the fact that the DFP algorithm strongly depends on the initial guess value, and the particle size distribution of limestone slurry cannot be truly reflected; therefore, the accuracy and adaptability of the DFP algorithm in measurement are poor.
Comparative example 2
The particle size distribution measurement was performed on the high concentration limestone slurry of example 1.
The method is substantially the same as example 1 except that step 3 is inverted using a non-negative least squares (NNLS) algorithm based on independent mode.
The non-negative least squares algorithm of this comparative example is as follows:
given a real m x n matrix A, whose rank k ≦ min (m, n), and a real m-dimensional vector b, a real n-dimensional vector x0 is found that minimizes the Ax-b Euclidean length. Meanwhile, in order to ensure the physical significance of the solution result, constraint x is added to be more than or equal to 0 for constraint.
The measurement results are shown in FIG. 11. The results in FIG. 11 show that: when the NNLS algorithm of the comparison example is adopted to invert the ultrasonic attenuation spectrum obtained in the embodiment 1, the influence of a tiny measurement error is difficult to overcome, so that obvious deviation occurs in the solution; therefore, the accuracy and adaptability of the non-negative least square algorithm of the comparison example are poor.
Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.
Claims (9)
1. A method for measuring the particle size of high-concentration slurry by using ultrasonic is characterized by comprising the following steps:
s1: placing an ultrasonic probe in the slurry to be detected, and acquiring an ultrasonic reflection signal of the slurry to be detected;
s2: processing the ultrasonic reflection signal by using a pulse echo method to obtain an ultrasonic attenuation spectrum;
s3: carrying out inversion on the ultrasonic attenuation spectrum by utilizing an ORT algorithm to obtain the granularity information of the slurry to be measured;
in step S1, the ultrasonic reflection signal includes a primary echo signalA 1 And secondary echo signalA 2 。
2. The method according to claim 1, wherein in step S2, the ultrasonic attenuation coefficient of the slurry to be tested is expressed as:
3. The method according to claim 1, wherein in step S3, the ORT algorithm is performed using the following formula:
wherein:Fdiscretizing volume frequency distribution for the slurry particles to be detected;Ais a matrix of attenuation coefficients;A T is composed ofAThe transposed matrix of (2);Gis a vector consisting of the ultrasonic attenuation at different frequencies;γis the weight of the fairing factor;His an optical ordered matrix.
4. The method of claim 3, wherein the fairing matrix is defined as:
。
5. a method according to claim 3, characterized in that the attenuation coefficient matrix is obtained from an ECAH model.
6. The method according to claim 1, wherein the ultrasonic probe comprises a housing, an ultrasonic transducer and a reflecting block, the ultrasonic transducer is arranged at the front end of the housing opposite to the reflecting block, a buffer block is arranged on one side of the ultrasonic transducer facing the reflecting block, a measuring area is formed between the buffer block and the reflecting block, and the distance between the buffer block and the reflecting block is adjustable.
7. The method of claim 6, wherein the spacing between the buffer block and the reflector block is between 5mm and 20 mm.
8. The method of claim 6, wherein the ultrasound probe has focusing means for focusing the ultrasound.
9. High concentration measurement by utilizing ultrasoundThe system for measuring the particle size of the slurry is characterized by comprising an ultrasonic probe, an ultrasonic pulse transmitting and receiving module, a signal amplification acquisition module and a data processing module, wherein the input end and the output end of the ultrasonic pulse transmitting and receiving module are respectively connected with the ultrasonic probe and the signal amplification acquisition module, the output end of the signal amplification acquisition module is connected with the data processing module, the data processing module comprises a first processing module and a second processing module, the first processing module processes ultrasonic reflection signals acquired by the signal amplification acquisition module by using a pulse echo method to obtain an ultrasonic attenuation spectrum, and the ultrasonic reflection signals comprise primary echo signalsA 1 And secondary echo signalA 2 And the second processing module utilizes an ORT algorithm to carry out inversion on the ultrasonic attenuation spectrum to obtain the particle size information of the slurry to be detected.
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5121629A (en) * | 1989-11-13 | 1992-06-16 | E. I. Du Pont De Nemours And Company | Method and apparatus for determining particle size distribution and concentration in a suspension using ultrasonics |
| US20040060356A1 (en) * | 2000-12-18 | 2004-04-01 | Scott David Mark | Method and apparatus for ultrasonic sizing of particles in suspensions |
| CN101135626A (en) * | 2007-09-27 | 2008-03-05 | 上海理工大学 | Grain graininess and concentration measuring method and device thereof |
| CN101169363A (en) * | 2007-09-27 | 2008-04-30 | 上海理工大学 | Granule graininess, concentration and density measuring method and device |
| CN101169364A (en) * | 2007-09-27 | 2008-04-30 | 上海理工大学 | Method and device for measuring discrete state granule graininess distribution |
| CN104330478A (en) * | 2014-11-14 | 2015-02-04 | 湖南五凌电力工程有限公司 | Probe and method for measuring steam turbine oil parameters |
-
2022
- 2022-08-24 CN CN202211021168.1A patent/CN115078191A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5121629A (en) * | 1989-11-13 | 1992-06-16 | E. I. Du Pont De Nemours And Company | Method and apparatus for determining particle size distribution and concentration in a suspension using ultrasonics |
| US20040060356A1 (en) * | 2000-12-18 | 2004-04-01 | Scott David Mark | Method and apparatus for ultrasonic sizing of particles in suspensions |
| CN101135626A (en) * | 2007-09-27 | 2008-03-05 | 上海理工大学 | Grain graininess and concentration measuring method and device thereof |
| CN101169363A (en) * | 2007-09-27 | 2008-04-30 | 上海理工大学 | Granule graininess, concentration and density measuring method and device |
| CN101169364A (en) * | 2007-09-27 | 2008-04-30 | 上海理工大学 | Method and device for measuring discrete state granule graininess distribution |
| CN104330478A (en) * | 2014-11-14 | 2015-02-04 | 湖南五凌电力工程有限公司 | Probe and method for measuring steam turbine oil parameters |
Non-Patent Citations (3)
| Title |
|---|
| 侯怀书: "《工业检测技术及应用从书 超声波纳米颗粒粒度分布测量技术及应用》", 31 July 2019, 上海科学技术出版社 * |
| 呼剑: "基于超声衰减谱法的纳米颗粒和水煤浆的粒度表征研究", 《中国优秀硕士学位论文全文数据库工程科技Ⅰ辑》 * |
| 贾楠 等: "基于超声谱分析的颗粒粒度测量研究", 《计量学报》 * |
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