Machine-made sand MB value automatic detection method and device based on ultrasonic velocity

Abstract

The invention discloses a machine-made sand MB value automatic detection method and device based on an ultrasonic velocity, and relates to the technical field of the construction industry, ultrasonic transmission data are collected through a detection device, the relation between the concentration of a methylene blue solution and the ultrasonic velocity in the solution is established, and the machine-made sand MB value detection method based on the ultrasonic velocity is innovatively provided. And a relation model capable of realizing MB value measurement through ultrasonic velocity is constructed, so that the adsorption performance of the to-be-measured machine-made sand is accurately evaluated. The detection device designed by the invention comprises a test module, a temperature compensation module and a central control system, realizes accurate output of the MB value of the machine-made sand, does not need to dropwise add a methylene blue solution for many times, can quickly perform multi-group sample tests, and has the advantages of simplicity and convenience in operation, high precision and intelligent analysis.

Description

Technical Field

[0001] The present invention relates to the technical field of the construction industry, and more particularly to an automatic detection method and device for MB value of machine-made sand based on ultrasonic velocity. Background Art

[0002] At present, river sand resources are decreasing, and machine-made sand has become the main substitute for concrete production. However, due to the limitations in the production process of machine-made sand, it often contains stone powder and mud powder. The mud powder is mainly composed of expansive clay minerals such as montmorillonite, and its particle size is often small. Particles with a particle size of less than 75μm have strong adsorption properties. Even if the content is not high, it will significantly affect the working performance and durability of concrete. In the prior art, the MB value is used to characterize the adsorption performance of particles with a particle size of less than 75μm in machine-made sand. The larger the MB value, the stronger the adsorption performance of fine particles within this particle size range. The current method for testing the MB value of machine-made sand mostly uses the "color halo method". The judgment standard is whether the upper layer solution after the machine-made sand and methylene blue solution are mixed and fully stirred can produce a stable color halo when titrated on filter paper. However, the "color halo method" has the following problems:

[0003] (1) Particles with a size of less than 75 μm have a strong adsorption capacity for methylene blue solution. Only when the clay ions within this particle size range are adsorbed to saturation will there be dyeing cations in the solution. At this time, a color halo will appear when the upper layer solution is titrated. However, in actual operation, a pipette is often used to add methylene blue solution, which has a certain operating error. In actual testing, multiple titrations are required, and the superposition of multiple errors will increase the error of the final total amount of methylene blue.

[0004] (2) The endpoint of the titration of methylene blue solution requires visual observation to see whether a light blue halo with a width of not less than 1 mm and which is stable for 5 minutes appears on the filter paper. However, in actual operation, even if a halo appears, it disappears quickly. Even if a certain amount of methylene blue solution is added again, the halo on the filter paper is still not clear enough. This makes it impossible to accurately judge the total amount of methylene blue solution added, resulting in inaccurate MB value test.

[0005] (3) During the titration process, a glass rod is used to dip the sample. The operation cannot ensure that the supernatant is consistent each time. The amount of titration will affect the diffusion speed of the methylene blue solution on the filter paper and the width of the blue halo obtained by diffusion.

[0006] (4) Each time the methylene blue solution is added, it takes about 5 minutes for the reaction to occur. If the addition is repeated multiple times, the test process will take more than half an hour, making it impossible to quickly test the MB value of large quantities of machine-made sand.

[0007] Although researchers have proposed improvements to the titration apparatus, the determination of the titration endpoint still requires visual inspection by test personnel, and the error caused by subjective judgment cannot be avoided. Although the colorimeter test method can use absorbance to determine the endpoint of the methylene blue solution titration, in order to ensure the accuracy of the absorbance, the supernatant after stirring needs to be diluted so that the colorimeter can effectively identify it. In addition, the methylene blue solution itself has color, and if the cuvette in the sample tank is not cleaned properly, it will have a significant impact on subsequent tests.

[0008] Therefore, how to realize automatic detection of MB value of machine-made sand and improve detection accuracy is an urgent problem to be solved by those skilled in the art. Summary of the invention

[0009] In view of this, the present invention provides an automatic detection method and device for the MB value of machine-made sand based on ultrasonic velocity, which can effectively avoid the influence of the subjective judgment of the test personnel on the test results and realize fast and efficient detection of the MB value of machine-made sand.

[0010] In order to achieve the above object, the present invention adopts the following technical solution:

[0011] An automatic detection device for MB value of machine-made sand based on ultrasonic velocity, comprising: an automatic stirring module, a pumping module, a testing module, a temperature compensation module, a central control system and a computing terminal;

[0012] The automatic stirring module fully stirs the solution in the beaker to obtain a solution to be tested;

[0013] The pumping module pumps the solution to be tested to the testing module;

[0014] The test module automatically detects the solution to be tested and transmits the test result, i.e., the phase signal, to the central control system;

[0015] The temperature compensation module tests the ambient temperature and transmits it to the central control system;

[0016] The central control system controls the ultrasonic unit, automatic stirring module and pumping module of the test module, and transmits the collected phase signal and ambient temperature to the computing terminal.

[0017] Preferably, the automatic stirring module includes an automatic lifting support, a base, a lifting platform, a stirring unit and a hanging basket;

[0018] One end of the automatic lifting support is fixed on the base, and a lifting slot is provided on the side wall of the automatic lifting support. A connecting block is provided on the edge of the lifting platform to fit the lifting slot; the connecting block is connected to the lifting slot through a hinge structure, and a support shaft, a hinge, a gear and a motor are provided in the lifting slot. The hinge is sleeved on the support shaft, the connecting block is fixedly connected to the hinge, the gear is meshed with the hinge, the motor is fixed in the lifting slot, and the output shaft of the motor is fixedly connected to the gear to drive the gear to rotate, thereby driving the hinge to rotate and move the lifting platform up and down; the motor is connected to the central control system;

[0019] The stirring unit includes several stirrers, each of which is equipped with a stirring blade on its output shaft, and the stirrer is electrically connected to the central control system; the stirrer is fixed on a lifting platform, and a beaker placement slot is provided on the base corresponding to the vertical direction of the stirring blade;

[0020] The hanging basket includes a mounting hook, a fixing ring, a fixing connecting rod, a basket body and a gasket. The bottom of the basket body is provided with an opening, and the gasket is provided with an opening; one end of the two fixing connecting rods is fixed on the fixing ring, and the other end is symmetrically fixed on the edge of the opening end of the basket body; the gasket is placed at the bottom of the basket body; the mounting hook is fixed on the mixer, and the fixing ring is hung, and the fixing ring is concentrically arranged with the output shaft of the mixer. After the gasket is installed in the basket body, a machine-made sand placement device can be formed, and filter paper for filtration is placed between the gasket and the basket body.

[0021] Preferably, the beaker containing the solution is provided with a liquid inlet and a liquid outlet at the upper and lower positions on the same side, respectively, and the beaker is placed in a beaker placement slot.

[0022] Preferably, the pumping module includes a peristaltic pump and a catheter, the liquid outlet at the bottom of each beaker is connected to the peristaltic pump through the catheter, and the peristaltic pump transports the solution to be tested to the test module through the catheter.

[0023] Preferably, the test module comprises a detection bracket, a detection tube and a fixing clamp, and the detection tube is fixed to the detection bracket by the fixing clamp;

[0024] The detection tube includes a central glass tube and an ultrasonic unit. The ultrasonic unit includes an ultrasonic transmitting probe and an ultrasonic receiving device. The ultrasonic transmitting probe is arranged at the top opening of the central glass tube, and the ultrasonic receiving device is arranged at the bottom of the central glass tube. An upper conduit connected to the liquid inlet of the beaker is arranged at the upper part of the central glass tube and below the ultrasonic transmitting probe. A lower conduit is arranged at the lower part of the central glass tube and above the ultrasonic receiving device, and is connected to a peristaltic pump through the conduit. The ultrasonic transmitting probe and the ultrasonic receiving device are connected to a central control system.

[0025] Preferably, the distance between the ultrasonic transmitting probe and the ultrasonic receiving device is the sound path, which is set according to requirements.

[0026] Preferably, the detection bracket includes a fixing plate, a bracket and a bottom plate, the fixing plate and the bottom plate are vertically fixedly connected via the bracket, and the fixing bracket is fixed on the fixing plate.

[0027] Preferably, the temperature compensation module includes a beaker and a temperature sensor, the temperature sensor is fixed in the beaker and connected to the central control system, distilled water is added to the beaker, and the temperature sensor is placed in the distilled water. Setting the temperature sensor can be used to consider the influence of temperature on the test results.

[0028] Preferably, the central control system includes an ultrasonic transmitting circuit and an ultrasonic receiving circuit, which are respectively connected to an ultrasonic transmitting probe and an ultrasonic receiving device.

[0029] An automatic detection method for MB value of machine-made sand based on ultrasonic velocity, comprising:

[0030] S1: Collect phase signals of distilled water, machine-made sand water solution and methylene blue solutions of different concentrations under the same ultrasonic velocity test at different ambient temperatures, and construct a concentration-time difference model of methylene blue solution under different temperature environments;

[0031] S2: adding a preset volume of standard methylene blue solution to the machine-made sand aqueous solution of the machine-made sand to be tested, to obtain the supernatant to be tested; collecting the phase signals of the distilled water, the machine-made sand aqueous solution and the supernatant to be tested under the same ultrasonic velocity test conditions at the current ambient temperature through the test module;

[0032] S3: The calculation terminal calculates the concentration of the adsorbed methylene blue solution in the upper clear liquid to be tested by using an interpolation method according to the current ambient temperature collected in S2, the phase signals of the three solutions and the methylene blue solution concentration-time difference model at the corresponding ambient temperature;

[0033] S4: Calculate the MB value of the machine-made sand to be tested according to the concentration of the methylene blue solution after adsorption.

[0034] Preferably, the supernatant to be tested is a supernatant obtained by adding a methylene blue solution to the machine-made sand aqueous solution obtained by filtering after the machine-made sand and distilled water are stirred, and then fully stirred and filtered by an automatic stirring module to obtain the supernatant after the machine-made sand adsorption is completed.

[0035] Preferably, the phase difference is calculated according to the three phase signals, the actual time difference of the ultrasonic transmission process of the methylene blue solution is calculated using the phase difference, and a three-dimensional curve is constructed according to the actual time difference and the corresponding ambient temperature and the concentration of the methylene blue solution to obtain a methylene blue solution concentration-time difference model;

[0036]

[0037] in, represents the phase signal of methylene blue solution, Represents the phase signal of the machine-made sand water solution, represents the phase signal of distilled water; It represents the phase difference of ultrasonic wave transmitted in distilled water. It represents the phase difference of ultrasonic wave in the machine-made sand aqueous solution and distilled water. It represents the phase difference of ultrasonic wave transmitted in methylene blue solution and distilled water;

[0038]

[0039] Δt=(t3-t1)-(t2-t1)

[0040] Δt represents the actual time difference; t1 is the time difference of ultrasonic wave transmission in distilled water when calibrating the zero-point concentration of distilled water, and the device takes 0 after calibration; t2 is the time difference of ultrasonic wave transmission in the machine-made sand aqueous solution and distilled water; t3 is the time difference of ultrasonic wave transmission in the methylene blue solution and distilled water.

[0041] Preferably, in S3, the expression for calculating the concentration of the methylene blue solution after adsorption by the interpolation method according to the methylene blue solution concentration-time difference model is:

[0042]

[0043] x i <x fina <x i+1

[0044] Among them, x fina is the concentration of methylene blue solution after adsorption in the supernatant to be measured; t′1 represents the time difference of ultrasonic wave propagation in distilled water calculated according to the distilled water phase signal in S2 when calibrating the zero concentration of distilled water, and the device takes 0 after calibration; t′2 represents the time difference of ultrasonic wave propagation in the machine-made sand aqueous solution and in distilled water calculated according to the phase signal of machine-made sand aqueous solution and the phase signal of distilled water in S2; t3′ represents the time difference of ultrasonic wave propagation in the supernatant to be measured and in distilled water calculated according to the phase signal of supernatant to be measured and the phase signal of distilled water in S2; ξ1 represents the temperature coefficient; T represents the current ambient temperature; (t′3-t′1)-(t′2-t′1) represents the actual time difference of the supernatant to be measured; Δt i Indicates the lower limit of the actual time difference in the methylene blue solution concentration-time difference model corresponding to the supernatant to be tested; Δt i+1 Indicates the actual time difference upper limit in the methylene blue solution concentration-time difference model corresponding to the supernatant to be tested; x i Indicates the concentration of methylene blue solution corresponding to the lower limit of the actual time difference; x i+1 Indicates the concentration of methylene blue solution corresponding to the upper limit of the actual time difference; Ti Indicates the ambient temperature corresponding to the lower limit of the actual time difference; T i+1 ) indicates the ambient temperature corresponding to the actual upper limit of the time difference.

[0045] Preferably, the expression for calculating the MB value of the machine-made sand to be tested according to the concentration of the methylene blue solution after adsorption is:

[0046]

[0047] Among them, x fina represents the concentration of methylene blue solution after adsorption; a represents the preset volume; C represents the standard methylene blue solution concentration; b represents the volume of the machine-made sand aqueous solution; c represents the weight of the machine-made sand to be tested used to prepare the machine-made sand aqueous solution in S2.

[0048] Preferably, when the equipment is used for the first time, it needs to be calibrated with methylene blue solutions of different concentrations, and the machine-made sand MB test can be carried out directly after the calibration is completed.

[0049] Preferably, the phase difference of distilled water is collected for automatic correction before S1 performs automatic calibration. Before adding methylene blue solutions of different concentrations to the beakers placed in the automatic stirring module, 600 mL of distilled water is first added to the three beakers. The test results obtained by adding distilled water can be used to avoid the equipment errors caused by the three detection tubes due to the device installation and the manufacturing errors of the mechanical structure of the device for ultrasonic testing. This error only needs to be performed once when the device is activated, and subsequent tests do not need to be corrected again. The test temperature is set to 20°C, and the temperature collected by the temperature compensation module is maintained at 20°C. The sound range is set to 15 cm, and ultrasonic transmitting probes and ultrasonic receiving devices are respectively set at the centers of the upper and lower bottom surfaces of the detection tube. The ultrasonic transmission frequency is selected as 200kHz, and the start button on the central control system operation panel is clicked for testing. After the test, click the automatic correction button, and the central control system will automatically eliminate the equipment error.

[0050] It can be seen from the above technical solutions that, compared with the prior art, the present invention discloses a method and device for automatically detecting the MB value of machine-made sand based on ultrasonic velocity, which is convenient and efficient to operate and has far-reaching significance for the effective utilization of the quality of machine-made sand. Specifically, the present invention has the following beneficial effects:

[0051] 1. Strong applicability and high intelligence. Each set of machine-made sand samples only needs to be dripped with methylene blue solution once to achieve BM value measurement, which reduces the superposition of reading errors caused by multiple dripping, greatly improves the test efficiency, and can quickly test multiple sets of samples.

[0052] 2. Based on the sensor signal during the detection process, the control terminal can realize precise testing with high sensitivity and intelligence. The whole test process is free from human operation errors and subjective judgments. The test results are accurate and the quantitative effect is good, which can better quantify the adsorption capacity of the machine-made sand to be tested. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0054] Figure 1 A schematic diagram of the structure of an automatic detection device for MB value of machine-made sand based on ultrasonic velocity provided by the present invention;

[0055] Figure 2 A schematic side view of the automatic stirring module provided by the present invention;

[0056] Figure 3 A schematic diagram of the top view of the automatic stirring module provided by the present invention;

[0057] Figure 4 A schematic diagram of the beaker structure provided by the present invention;

[0058] Figure 5 A schematic diagram of the hanging basket structure provided by the present invention;

[0059] Figure 6 A schematic diagram of the bottom structure of the basket provided by the present invention;

[0060] Figure 7 A schematic diagram of the side view of the rear hanging basket after the gasket is installed provided by the present invention;

[0061] Figure 8 A schematic diagram of the structure of the pumping module provided by the present invention;

[0062] Fig. 9 A schematic diagram of the side structure of the test module provided by the present invention;

[0063] Fig.10 A schematic diagram of the front view structure of the test module provided by the present invention;

[0064] Fig.11 A schematic diagram of the structure of the detection tube provided by the present invention;

[0065] Fig.12 This is a schematic diagram of the structure of the temperature compensation module provided by the present invention. DETAILED DESCRIPTION

[0066] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0067] The embodiment of the present invention discloses an automatic detection device for MB value of machine-made sand based on ultrasonic velocity, comprising: an automatic stirring module, a pumping module, a test module, a temperature compensation module, a central control system and a computing terminal; the automatic stirring module fully stirs the solution in the beaker to obtain a solution to be tested; the pumping module pumps the solution to be tested to the test module; the test module automatically detects the solution to be tested, and transmits the electrical signal (phase signal) of the detection result to the central control system; the temperature compensation module tests the ambient temperature, and transmits the ambient temperature to the central control system, and the calibration curve constructed by the device test is obtained at 20°C, and the calibration curve is used to avoid the influence of temperature on the ultrasonic velocity; the central control system controls the ultrasonic unit, the automatic stirring module, the pumping module and the pumping module of the test module, and transmits the collected phase signal and ambient temperature to the computing terminal.

[0068] Furthermore, the automatic mixing module includes an automatic lifting support, a base, a lifting platform, a mixing unit and a hanging basket; one end of the automatic lifting support is fixed on the base, a lifting groove is provided on the side wall of the automatic lifting support, and a connecting block is provided on the edge of the lifting platform to match and install with the lifting groove; the connecting block and the lifting groove are connected by a hinge structure, and a support shaft, a hinge, a gear and a motor are provided in the lifting groove, the hinge is sleeved on the support shaft, the connecting block is fixedly connected to the hinge, the gear is meshed with the hinge, the motor is fixed in the lifting groove, and the output shaft of the motor is fixedly connected to the gear to drive the gear to rotate, thereby driving the hinge to rotate and make the lifting platform move up and down. ; The motor is connected to the central control system; The stirring unit includes several stirrers, each of which is equipped with a stirring blade on its output shaft, and the stirrer is electrically connected to the central control system; The stirrer is fixed on a lifting platform, and a beaker placement slot is provided on the base corresponding to the vertical direction of the stirring blade; The hanging basket includes a mounting hook, a fixing ring, a fixing connecting rod, a basket body and a gasket, and the bottom of the basket body is provided with an opening, and the gasket is provided with an opening; One end of the two fixing connecting rods is fixed on the fixing ring, and the other end is symmetrically fixed on the edge of the opening end of the basket body; The gasket is placed at the bottom of the basket body; The mounting hook is fixed on the stirrer, and a fixing ring is hung, and the fixing ring is concentrically arranged with the output shaft of the stirrer. After the gasket is installed in the basket body, a machine-made sand placement device can be formed, and filter paper for filtering is placed between the gasket and the basket body.

[0069] Furthermore, the beaker containing the solution is provided with a liquid inlet and a liquid outlet at the upper and lower positions on the same side, respectively.

[0070] Furthermore, the pumping module includes a peristaltic pump and a catheter. The liquid outlet at the bottom of each beaker is connected to the peristaltic pump through the catheter, and the peristaltic pump transports the solution to be tested to the test module through the catheter.

[0071] Furthermore, the test module includes a detection bracket, a detection tube and a fixing clamp, and the detection tube is fixed to the detection bracket by the fixing clamp; the detection tube includes a central glass tube and an ultrasonic unit, the ultrasonic unit includes an ultrasonic transmitting probe and an ultrasonic receiving device, the ultrasonic transmitting probe is arranged at the top opening of the central glass tube, and the ultrasonic receiving device is arranged at the bottom of the central glass tube; an upper conduit connected to the liquid inlet of the beaker is arranged at the upper part of the central glass tube and below the ultrasonic transmitting probe; a lower conduit is arranged at the lower part of the central glass tube and above the ultrasonic receiving device, and is connected to the peristaltic pump through the conduit; the ultrasonic transmitting probe and the ultrasonic receiving device are connected to the central control system.

[0072] Furthermore, the detection bracket includes a fixing plate, a bracket and a bottom plate. The fixing plate and the bottom plate are vertically fixedly connected through the bracket, and the fixing bracket is fixed on the fixing plate.

[0073] Furthermore, the temperature compensation module includes a beaker and a temperature sensor, the temperature sensor is fixed in the beaker and connected to the central control system, distilled water is added to the beaker, and the temperature sensor is placed in the distilled water. Setting the temperature sensor can be used to consider the influence of temperature on the test results.

[0074] On the other hand, a monitoring method of an automatic detection device for MB value of machine-made sand based on ultrasonic velocity comprises the following steps:

[0075] S1: Collect phase signals of distilled water, machine-made sand water solution and methylene blue solutions of different concentrations under the same ultrasonic velocity test at different ambient temperatures. The ultrasonic wave will produce a phase difference after passing through the same sound path L in different solutions. The time difference is calculated based on the phase difference, and a concentration-time difference model of methylene blue solution under different temperature environments is constructed;

[0076] S2: adding a preset volume of standard methylene blue solution to the machine-made sand aqueous solution of the machine-made sand to be tested to obtain the supernatant to be tested; collecting the phase signal of the supernatant to be tested under the current ambient temperature conditions through the test module;

[0077] S3: Calculate the concentration of the adsorbed methylene blue solution in the supernatant to be tested by using an interpolation method according to the current ambient temperature, the phase signal of the supernatant to be tested and the corresponding methylene blue solution concentration-time difference model;

[0078] S4: Calculate the MB value of the machine-made sand to be tested according to the concentration of the methylene blue solution after adsorption.

[0079] Example 1

[0080] This embodiment provides a device for detecting MB value of machine-made sand based on ultrasonic velocity, including: an automatic stirring module, a pumping module, a testing module, a temperature compensation module, a central control system and a computing terminal, wherein the automatic stirring module, the pumping module and the testing module are respectively connected to the central control system 29, and the central control system 29 is connected to the computing terminal 30, such as Figure 1 shown.

[0081] The automatic stirring module can fully stir the machine-made sand and distilled water in the beaker to form a suspension;

[0082] The pumping module can pump the test solutions in the three beakers into the corresponding glass test containers;

[0083] The test module can detect the concentration of the supernatant of distilled water, distilled water after machine-made sand adsorption, and methylene blue solution. By setting a high-precision ultrasonic transmitting probe and an ultrasonic receiving device to effectively capture the phase signal during ultrasonic transmission in different solutions, the test solution can be automatically detected, and the phase signal can be transmitted to the computing terminal through the central control system for processing;

[0084] The temperature compensation module can be used to test the ambient temperature. The methylene blue solution concentration-time difference standard curve of the equipment is obtained under a 20°C environment. The temperature compensation module can obtain the temperature T of the solution in the current test environment and transmit it to the computing terminal for processing through the central control system;

[0085] The central control system is used for ultrasonic measurement signal processing. It is connected to the ultrasonic transmitting probe and the ultrasonic receiving device through the ultrasonic transmitting circuit and the ultrasonic receiving circuit respectively. After processing, the phase signal in the ultrasonic transmission process in different test devices can be obtained.

[0086] Specifically, the automatic stirring module includes an automatic lifting support 1, a lifting tank 2, a base 3, a lifting platform 4, a stirrer, a stirring blade, a mounting hook, a beaker placement tank, a beaker, a basket body 10 and a gasket 11.

[0087] Further, the mixer includes a first mixer 501, a second mixer 502 and a third mixer 503, the stirring blade 6 includes a first stirring blade 601, a second stirring blade 602 and a third stirring blade 603, the mounting hook 7 includes a first mounting hook 701, a second mounting hook 702 and a third mounting hook 703, and the beaker placement groove 8 includes a first beaker placement groove 801, a second beaker placement groove 802 and a third beaker placement groove 803, as shown in FIG. Figure 2 As shown, the base 3 is provided with a first beaker placement slot 801, a second beaker placement slot 802 and a third beaker placement slot 803, as shown in FIG. Figure 3 As shown;

[0088] The beakers include a first beaker 901, a second beaker 902 and a third beaker 903, wherein the first beaker 901 is respectively provided with a first liquid outlet 1201 and a first liquid inlet 1301, the second beaker 902 is respectively provided with a second liquid outlet 1202 and a second liquid inlet 1302, and the third beaker 903 is respectively provided with a third liquid outlet 1203 and a third liquid inlet 1303. Figure 4 As shown;

[0089] The hanging basket 10 includes a first hanging basket 1001, a second hanging basket 1002 and a third hanging basket 1003, wherein the first hanging basket 1001 is respectively provided with a first fixing ring 1401, a first fixing connecting rod 1501 and a first basket body 1601, wherein the first basket body 1601 has a bottom opening, the second hanging basket 1002 is respectively provided with a second fixing ring 1402, a second fixing connecting rod 1502 and a second basket body 1602, wherein the second basket body 1602 has a bottom opening, and the third hanging basket 1003 is respectively provided with a third fixing ring 1403, a third fixing connecting rod 1503 and a third basket body 1603, wherein the third basket body 1603 has a bottom opening, as shown in FIG. Figure 5-6 As shown;

[0090] The gasket 11 includes a first gasket 1101, a second gasket 1102 and a third gasket 1103. The gasket is provided with openings for filtering. After the gasket 11 is installed in the hanging basket 10, a machine-made sand placing device can be formed. Figure 7 shown.

[0091] Further, the pumping module includes a peristaltic pump and a catheter, the peristaltic pump includes a first peristaltic pump 1701, a second peristaltic pump 1702 and a third peristaltic pump 1703, and the catheter includes a first catheter 1801, a second catheter 1802 and a third catheter 1803, such as Figure 8 As shown;

[0092] Furthermore, the test module includes a detection bracket 19, a detection tube 20, and a detection tube fixing clamp 21. Fig. 9 As shown, the detection tube 20 includes a first detection tube 2001, a second detection tube 2002 and a third detection tube 2003, and the detection tube fixing clamp 21 includes a first detection tube fixing clamp 2101, a second detection tube fixing clamp 2102 and a third detection tube fixing clamp 2103. Fig.10 As shown;

[0093] The first detection tube 2001 includes a first central glass tube 2201, a first ultrasonic transmitting probe 2301 and a first ultrasonic receiving device 2401, wherein a first lower conduit (liquid inlet) 2501 is arranged below the first central glass tube 2201, and a first upper conduit (liquid outlet) 2601 is arranged above the first central glass tube 2201. Fig.11As shown; the second detection tube 2002 includes a second central glass tube 2202, a second ultrasonic transmitting probe 2302 and a second ultrasonic receiving device 2402, wherein a second lower conduit (liquid inlet) 2502 is arranged below the second central glass tube 2202, and a second upper conduit (liquid outlet) 2602 is arranged above the second central glass tube 2202; the third detection tube 2003 includes a third central glass tube 2203, a third ultrasonic transmitting probe 2303 and a third ultrasonic receiving device 2403, wherein a third lower conduit (liquid inlet) 2503 is arranged below the third central glass tube 2203, and a third upper conduit (liquid outlet) 2603 is arranged above the third central glass tube 2203.

[0094] Furthermore, the temperature compensation module includes a beaker 27 and a temperature sensor 28, such as Fig.12 shown.

[0095] Example 2

[0096] This embodiment discloses a detection method of a machine-made sand MB value detection device based on ultrasonic velocity, comprising the following steps:

[0097] S1. Collect phase signals of distilled water, machine-made sand water solution and methylene blue solutions of different concentrations under the same ultrasonic velocity test at different ambient temperatures, and construct a concentration-time difference model of methylene blue solution under different temperature environments;

[0098] S2. Add a preset volume of standard methylene blue solution into the machine-made sand aqueous solution prepared by the machine-made sand to be tested, to obtain a supernatant to be tested; and search the methylene blue solution concentration corresponding to the supernatant by reference to the model;

[0099] S3. Calculate the total amount of methylene blue adsorbed by the machine-made sand by the difference between the initial concentration of the methylene blue solution and the concentration of the methylene blue solution in the supernatant, and then obtain the MB value of the machine-made sand to be tested.

[0100] Furthermore, in S1, the ultrasonic wave will show different propagation speeds in methylene blue solutions of different concentrations. Since the ultrasonic wave speed is relatively fast, the test error is relatively large when the fixed distance measurement L and the quotient of time t are directly used for analysis (L / t). Therefore, the phase difference is used for testing in this embodiment. The automatic stirring module can fully stir the machine-made sand and distilled water in the beaker, the solution after the machine-made sand and distilled water are stirred, and the methylene blue solution to form a suspension. The beaker can also contain distilled water; the pumping module can pump the solution to be tested in the three beakers into the central glass tube of the corresponding test module; the test module can detect the concentration of distilled water, distilled water after adsorption by machine-made sand, and the upper clear liquid of methylene blue after adsorption by machine-made sand. By setting a high-precision ultrasonic transmitting probe and an ultrasonic receiving probe, the phase difference in the ultrasonic transmission process in the central glass tube can be effectively captured, and the automatic detection of the solution to be tested can be realized, and the calculated electrical signal can be transmitted to the central control system for processing; the acoustic impedance of distilled water to ultrasonic waves is very small. As the concentration of methylene blue solution increases, the density of the solution continues to increase, and the acoustic impedance of the solution to ultrasonic waves will gradually increase;

[0101] The temperature compensation module can be used to test the ambient temperature. The standard curve of the equipment's "methylene blue solution concentration-time difference" is obtained under a 20°C environment. The temperature compensation module can obtain the temperature of the solution in the current test environment, which is used to obtain the temperature T in the ultrasonic calculation equation.

[0102] The central control system is used for ultrasonic signal processing, and is connected to the ultrasonic transmitting probe and the ultrasonic receiving probe through the ultrasonic transmitting circuit and the ultrasonic receiving circuit respectively. After processing, the phase difference in the ultrasonic transmission process in different test devices can be obtained;

[0103] The calculation terminal is used to display and output the specific measured results, including temperature, phase difference, time difference, ultrasonic transmission time, concentration of methylene blue solution in the supernatant, the total amount of methylene blue adsorbed by the machine-made sand, and the MB value of the machine-made sand calculated by the built-in program.

[0104] Furthermore, an indirect test method is used for testing. After the ultrasonic waves in the three test circuits pass through the same sound path L of different solutions, a phase difference will be generated. The standard curve of "solution concentration-time difference" is obtained by using the phase difference and the concentration of the solution to be tested. The steps include:

[0105] S11, preparing methylene blue solutions of different concentrations;

[0106] Take the preparation of a 10g / L methylene blue test standard solution as an example: According to the provisions of GB / T 14684-2022 "Construction Sand", the concentration of the standard methylene blue solution used for MB value detection is 10g / L. The process of preparing the standard methylene blue solution is as follows: dry the methylene blue powder, accurately weigh 10g of the dried methylene blue powder for use; pour 600mL of distilled water into a clean beaker and heat it to 35-40℃ with an alcohol lamp, then transfer the weighed 10g of methylene blue powder to the beaker completely and stir it with a glass rod for 40 minutes until the powder is completely dissolved; after observing that the methylene blue powder is completely dissolved, wait for the solution to cool naturally to 20℃, prepare a clean brown volumetric flask, and put the prepared The good solution was transferred to a brown volumetric flask, and the beaker and glass rod were rinsed with distilled water to ensure that the methylene blue solution was completely transferred. Distilled water was added to the brown volumetric flask at 20±1°C until the scale line corresponding to 1L of the volumetric flask was reached. For methylene blue solutions of other concentrations, the weighed methylene blue powder was changed to 0g, 2g, 4g, 6g and 8g, respectively. The concentrations were 0g / L (distilled water), 2g / L, 4g / L, 6g / L and 8g / L, respectively. The solution preparation process was the same as above. Five beakers, five glass rods and five dark-colored volumetric flasks with a capacity of 1L were prepared, or a standard methylene blue solution was used to obtain the solution by dilution.

[0107] S12, calibrating the test module in the device using distilled water;

[0108] After the device is activated for the first time, it is necessary to avoid equipment errors caused by the installation of ultrasonic probes, etc. After all concentrations of methylene blue solutions are prepared, 600 mL of distilled water is respectively placed in the three glass beakers of the automatic stirring module in the device. The test temperature is set to 20°C, the sound range (i.e., the distance between the ultrasonic transmitting probe and the ultrasonic receiving device) is 15 cm, and the ultrasonic transmission frequency in the ultrasonic unit is 200 kHz. Click the "start" button on the central control system operation panel to test. The pumping module pumps distilled water into the corresponding three test tubes. After the test tubes are filled, the ultrasonic transmitting probe and the ultrasonic receiving device automatically start ultrasonic testing and transmit the measured phase difference to the central control system. After the test, click the "Auto-Calibration" button, and the central control system will automatically eliminate the equipment error.

[0109] The test results obtained by adding distilled water can be used to avoid the equipment error caused by the installation of the three detection tubes and the manufacturing error of the mechanical structure of the device. This error only needs to be performed once when the device is activated, and no correction is required for subsequent tests. After the correction is completed, there is no need to retest and calibrate the subsequent tests. The device comes with a temperature compensation module to eliminate the influence of temperature on the test results.

[0110] S13, after error correction, the relationship between the concentration of methylene blue solution and ultrasonic velocity is obtained. Two beakers can be selected for testing. Here, distilled water and a methylene blue solution with a concentration of 2 g / L are added to the first and second beakers of automatic stirring, respectively. Click the start button on the central control system operation panel to test. Each concentration of the sample to be tested is tested 5 times and the average is taken as the interpolation point of the "methylene blue solution concentration-time difference" standard curve. In order to obtain more data values, methylene blue solutions of corresponding concentrations can also be added to the second and third beakers. Similarly, each concentration sample is tested 5 times and the average is taken as the interpolation point;

[0111] When only the second beaker is used, after the test is completed, only the device corresponding to the second beaker needs to be cleaned, and then methylene blue solutions of other concentrations are added thereto. When the methylene blue solutions with concentrations of 2g / L, 4g / L, 6g / L, 8g / L and 10g / L are tested, the "methylene blue solution concentration-time difference" standard curve can be obtained. The curve can be automatically saved to the central control system as a standard curve, and can also be exported to the computing terminal as a backup of the standard curve. It can be called at any time for different methylene blue samples. This curve can also be used to calibrate the concentration of methylene blue solutions of uncertain concentrations. For methylene blue solutions of unknown concentrations, the concentration can be calculated by testing the phase difference between it and distilled water. For one concentration of methylene blue, the curve only needs to be tested once, and no re-calibration is required for subsequent tests.

[0112] Furthermore, the time difference of ultrasonic wave propagation in different solutions is obtained based on the phase difference calculated from the three phase signals;

[0113]

[0114] in, represents the phase signal of methylene blue solution, Represents the phase signal of the machine-made sand water solution, represents the phase signal of distilled water; It represents the phase difference of ultrasonic wave transmitted in distilled water. It represents the phase difference of ultrasonic wave in the machine-made sand aqueous solution and distilled water. It represents the phase difference of ultrasonic wave transmitted in methylene blue solution and distilled water;

[0115] Δt represents the actual time difference of the transmission of the methylene blue solution; t1 is the time difference of the ultrasonic wave in the distilled water when the zero concentration is calibrated, and the device takes 0 after calibration; t2 is the time difference of the ultrasonic wave in the machine-made sand aqueous solution and distilled water; t3 is the time difference of the ultrasonic wave in the methylene blue solution and distilled water. The actual time difference is calculated to exclude the existence of ions in the upper clear liquid after the machine-made sand is dissolved in the actual detection process, which affects the transmission time of the ultrasonic wave in the upper clear liquid.

[0116] Furthermore, based on the above test data, the relationship between the phase difference of ultrasonic waves transmitted in distilled water and the solution to be tested (methylene blue solution of different concentrations or machine-made sand aqueous solution), the concentration of methylene blue solution and the temperature is established; the basic principle of the test of the MB value of machine-made sand based on ultrasonic velocity is that when the sizes of the two test devices are the same, the relationship between the ultrasonic velocity and the solution concentration is:

[0117]

[0118] Among them, C0 is the propagation speed of ultrasound in distilled water at 0°C; when the temperature changes, the temperature coefficient ξ1 in distilled water can be corrected; ξ2 is the solution concentration proportional coefficient when ultrasound propagates in the solution to be tested; when the solution temperature is T, the propagation speed of ultrasound in distilled water is C td , the propagation speed in the solution to be tested is C tx , the concentration of the solution to be tested is x;

[0119] When the ultrasonic propagation distance in the test device, i.e., the sound distance, is L, the time required for ultrasonic waves to propagate in different solutions can be calculated according to the following formula 2:

[0120]

[0121] Wherein, L is the distance between the ultrasonic transmitting probe and the ultrasonic receiving device in the test device; t1″ and t2″ are the time required for the ultrasonic wave to propagate a distance of L in the test solution and distilled water respectively; ΔL is the dimensional error of the test device caused by installation, etc., which can be eliminated by filling both devices with distilled water for testing;

[0122] The time difference when ultrasonic waves propagate in different solutions can be analyzed by combining equations 1 and 2 to obtain the time difference calculation formula, as shown in equation 3:

[0123]

[0124] By transforming the form of formula 1, the relationship between the transmission speed of ultrasound in solutions of different concentrations can be obtained as shown in formula 4:

[0125]

[0126] Since ξ2x is a high-order infinitesimal quantity of 1, Formula 3 is simplified, and Formula 5 is the simplified ultrasonic time difference calculation formula:

[0127]

[0128] Ultrasonic velocity can be expressed as the quotient of sound distance and propagation time (L / t). Since ultrasonic velocity propagates quickly and the ultrasonic test interval is small, direct time testing will result in large errors. Therefore, the direct test of time difference is converted into the phase difference measured by electrical signals for analysis; phase difference f is the ultrasonic emission frequency, let Substituting into equation 5, the relationship between solution concentration and Δt can be obtained as shown in equation 6.

[0129]

[0130] From formula 6, the solution concentration calculation equation can be obtained as shown in formula 7:

[0131]

[0132] In order to deal with the equipment error caused by the installation size of the test device, distilled water is filled in both test devices. After testing the phase difference, the equipment error at zero concentration can be calibrated. When x = 0, T = T0, Δt = Δt0, the size error of the equipment caused by installation can be calculated by formula 8:

[0133]

[0134] When the solution concentration in the test device is x1, T = T1, Δt = Δt1, then

[0135]

[0136] Substituting equations 8 and 9 into equation 7, we can know that the explicit expression of the solution concentration x is shown in equation 10. It can be seen that x is related to ξ1, T0, T1, x1, Δt0, and Δt1. After calibration, the temperature coefficient ξ1 corresponding to the solution concentration of x1 can be obtained, and the remaining parameters can be directly obtained. The unknown quantities at this time are the time difference Δt and the temperature T. Δt can be obtained through the phase difference Calculate; it can be known that the expression for solving the solution concentration x is:

[0137]

[0138] Extending formula 10 to [x i , x i+1 ], the concentration calculation formula at any point in any two interpolation node intervals of the calibration curve can be obtained as shown in formula 11:

[0139]

[0140] After obtaining the generalized formula, the phase difference is used in an iterative manner to calculate the liquid concentration values ​​in different concentration ranges. Considering that ions of machine-made sand may dissolve in the solution and affect the phase difference, equation 11 is corrected to obtain an equation considering the dissolution of machine-made sand ions as shown in equation 12:

[0141]

[0142] x i <x fina <x i+1 (12)

[0143] In formula 12, x fina In order to consider the concentration of methylene blue solution after adsorption in the supernatant to be tested after the ions in the machine-made sand are dissolved, t′1 represents the time difference of ultrasonic wave transmission in distilled water; t′2 represents the time difference of ultrasonic wave transmission in the machine-made sand aqueous solution and distilled water; t′3 represents the time difference of ultrasonic wave transmission in the supernatant to be tested and distilled water; ξ1 represents the temperature coefficient; T represents the current ambient temperature; Δt i Indicates the lower limit of the actual time difference in the methylene blue solution concentration-time difference model corresponding to the supernatant to be tested; Δt i+1 Indicates the actual time difference upper limit in the methylene blue solution concentration-time difference model corresponding to the supernatant to be tested; x i Indicates the concentration of methylene blue solution corresponding to the lower limit of the actual time difference; x i+1 Indicates the concentration of methylene blue solution corresponding to the upper limit of the actual time difference; T i Indicates the ambient temperature corresponding to the lower limit of the actual time difference; T i+1 ) indicates the ambient temperature corresponding to the actual upper limit of the time difference.

[0144] Furthermore, in S3, the relationship between the concentration of methylene blue solution and the ultrasonic velocity is that as the concentration of methylene blue increases, the ultrasonic velocity continues to decrease. In actual tests, the machine-made sand continuously adsorbs methylene blue, and the ultrasonic velocity continues to decrease. The smaller the phase difference measured by the device, the stronger the adsorption of the machine-made sand on the methylene blue solution. It can be seen from formula 12 that after the equipment is activated and calibrated with distilled water, the concentration of methylene blue solution is only related to the phase difference of the ultrasonic velocity in the machine-made sand aqueous solution and the supernatant to be tested after adding the methylene blue solution to the machine-made sand aqueous solution. The total amount of methylene blue adsorbed by the machine-made sand is calculated by the difference between the initial concentration of the methylene blue solution and the concentration of methylene blue in the supernatant, and then the MB value of the machine-made sand to be tested is obtained, specifically according to the following steps:

[0145] First, complete and undamaged filter papers are placed in the basket bodies of multiple hanging baskets respectively, and after placement, corresponding gaskets are placed on top of the filter papers. The three hanging baskets in the automatic stirring module with installed filter papers and gaskets are placed in the first beaker, the second beaker and the third beaker in the automatic stirring module respectively, and then installed on the installation hook in the automatic stirring module through the fixing ring on the fixing connecting rod; distilled water is added to the beaker in the temperature compensation module, and the temperature sensor is placed in the distilled water;

[0146] Secondly, the machine-made sand samples to be tested are screened, dried and cooled, and three 200g machine-made sand samples to be tested are taken out by the method of reduced sampling for standby use. 500±5mL of distilled water are added to the first beaker, the second beaker and the third beaker respectively, and the three weighed machine-made sand samples to be tested are poured into the first beaker, the second beaker and the third beaker respectively. Click the start button on the operation panel of the central control system to test. The temperature compensation module automatically obtains the temperature of the solution in the current test environment. The lifting platform installed with the mixer drives the hanging basket to descend, so that the machine-made sand sample to be tested is completely immersed in the distilled water in the beaker. Then the mixer is started, and the stirring blade stirs the solution. According to the set built-in program, it is first stirred at a speed of 600±60rpm for 5min, and then stirred at a speed of 400rpm for 2min. Then the lifting platform drives the hanging basket to rise, and the machine-made sand water solution in the hanging basket flows back to the beaker by filtration. The pumping module is a peristaltic pump. The machine-made sand water solution in the three beakers is pumped into the detection tube of the test module. When the detection tube is filled with the machine-made sand water solution, the ultrasonic unit automatically The phase of the aqueous solution after the machine-made sand is stirred in the detection tube at this time is tested, and then the time difference t2 of the ultrasonic wave transmission in the machine-made sand aqueous solution and the distilled water is obtained. After the detection is completed, the central control system controls the peristaltic pump to reverse according to the set program to reflux the solution in the detection tube. After the reflux is completed, the lifting platform installed with the stirrer drives the hanging basket to descend again, and the stirring is restarted. At the same time, 100mL of a standard methylene blue solution with a concentration of 10g / L is added to the three beakers at one time. After the total stirring time is up to 3 minutes, the lifting platform drives the hanging basket to rise, and the upper clear liquid to be tested after the machine-made sand adsorption is obtained by filtering; the central control system controls the peristaltic pump to start again according to the set program, and pumps the upper clear liquid to be tested into the detection tube of the test module. When the detection tube is filled with the upper clear liquid to be tested, the ultrasonic unit automatically tests the phase of the upper clear liquid to be tested in the detection tube at this time, and then the time difference t3 of the ultrasonic wave transmission in the upper clear liquid to be tested and the distilled water is obtained;

[0147] Finally, the central control system automatically receives and analyzes the ultrasonic transmission data twice. According to formula 12, the concentration of methylene blue solution in the supernatant to be tested can be obtained. fina g / L; according to the initial concentration of the standard methylene blue solution x0 = 10g / L and the measured concentration of the methylene blue solution in the supernatant to be tested xfina g / L, and the MB value of machine-made sand is calculated according to formula 13:

[0148]

[0149] In formula 13, MB is the methylene blue value (g / kg), which means the number of grams of methylene blue consumed per unit mass (kg) of machine-made sand, and x fina This indicates the concentration of methylene blue in the supernatant after the machine-made sand is adsorbed; 0.2 kg is the weight of the machine-made sand sample to be tested. The calculation equation 13 is preset in the calculation terminal. After each test, the data exported by the central control system include temperature, phase signal, concentration of methylene blue solution in the supernatant, total amount of methylene blue adsorbed by the machine-made sand, and MB value of the machine-made sand calculated by the built-in program of the calculation terminal.

[0150] Example 3

[0151] Common tuff, limestone, basalt, granite and gneiss artificial sand in engineering were used as samples to be tested, and the "color halo method" and the ultrasonic velocity-based test method provided in the embodiment were used to detect the MB value of artificial sand. The MB values ​​measured by the two different test methods are shown in Table 1. As can be seen from Table 1, the ultrasonic velocity-based artificial sand MB value test method can more accurately obtain the MB value of artificial sand, and achieve a more accurate evaluation of the adsorption performance of artificial sand. The test process shows that for artificial sand with strong adsorption, such as basalt artificial sand, the "color halo method" is set to 5mL in a single titration. The number of repeated additions of methylene blue solution exceeds 10 times, and the test time is long. The ultrasonic-based test method only needs to be added once, which can greatly shorten the test time and ensure that a large number of artificial sand MB value tests can be completed in a short time.

[0152] Table 1 MB values ​​of machine-made sand measured by different test methods

[0153]

[0154]

[0155] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0156] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An automatic detection device for MB value of machine-made sand based on ultrasonic velocity, characterized in that: include: Automatic stirring module, pumping module, testing module, temperature compensation module, central control system and computing terminal; The automatic stirring module fully stirs the solution in the beaker to obtain a solution to be tested; The pumping module pumps the solution to be tested to the testing module; The test module automatically detects the solution to be tested and transmits the detected phase signal to the central control system; The temperature compensation module tests the ambient temperature and transmits it to the central control system; The central control system controls the ultrasonic unit, automatic stirring module and pumping module of the test module, and transmits the collected phase signal and ambient temperature to the computing terminal.

2. The automatic detection device for MB value of machine-made sand based on ultrasonic velocity according to claim 1 is characterized in that: The automatic mixing module includes an automatic lifting support, a base, a lifting platform, a mixing unit and a hanging basket; One end of the automatic lifting support is fixed on the base, a lifting slot is provided on the side wall of the automatic lifting support, a connecting block is provided on the edge of the lifting platform to fit the lifting slot; the connecting block is connected to the lifting slot through a hinge structure, a support shaft, a hinge, a gear and a motor are provided in the lifting slot, the hinge is sleeved on the support shaft, the connecting block is fixedly connected to the hinge, the gear is meshed with the hinge, the motor is fixed in the lifting slot, and the output shaft of the motor is fixedly connected to the gear; the motor is connected to the central control system; The stirring unit includes several stirrers, each of which is equipped with a stirring blade on its output shaft, and the stirrer is electrically connected to the central control system; the stirrer is fixed on a lifting platform, and a beaker placement slot is provided on the base corresponding to the vertical direction of the stirring blade; The hanging basket includes an installation hook, a fixing ring, a fixing connecting rod, a basket body and a gasket. An opening is arranged at the bottom of the basket body, and an opening is arranged at the gasket. One end of two fixing connecting rods is fixed on the fixing ring, and the other end is symmetrically fixed on the edge of the opening end of the basket body. The gasket is placed at the bottom of the basket body. The installation hook is fixed on the mixer, and the fixing ring is hung. The fixing ring is arranged concentrically with the output shaft of the mixer.

3. The automatic detection device for MB value of machine-made sand based on ultrasonic velocity according to claim 1 is characterized in that: The beaker containing the solution is respectively provided with a liquid inlet and a liquid outlet at the upper and lower positions on the same side, and the beaker is placed in a beaker placing groove.

4. The automatic detection device for MB value of machine-made sand based on ultrasonic velocity according to claim 3 is characterized in that: The pumping module includes a peristaltic pump and a catheter. The liquid outlet at the bottom of each beaker is connected to the peristaltic pump through the catheter. The peristaltic pump transports the solution to be tested to the test module through the catheter.

5. The automatic detection device for MB value of machine-made sand based on ultrasonic velocity according to claim 4 is characterized in that: The test module includes a detection bracket, a detection tube and a fixing clamp, and the detection tube is fixed on the detection bracket by the fixing clamp; The detection tube includes a central glass tube and an ultrasonic unit. The ultrasonic unit includes an ultrasonic transmitting probe and an ultrasonic receiving device. The ultrasonic transmitting probe is arranged at the top opening of the central glass tube, and the ultrasonic receiving device is arranged at the bottom of the central glass tube. An upper conduit connected to the liquid inlet of the beaker is arranged at the upper part of the central glass tube and below the ultrasonic transmitting probe. A lower conduit is arranged at the lower part of the central glass tube and above the ultrasonic receiving device, and is connected to a peristaltic pump through the conduit. The ultrasonic transmitting probe and the ultrasonic receiving device are connected to a central control system.

6. The automatic detection device for MB value of machine-made sand based on ultrasonic velocity according to claim 1 is characterized in that: The temperature compensation module includes a beaker and a temperature sensor. The temperature sensor is fixed in the beaker and connected to the central control system.

7. An automatic detection method for MB value of machine-made sand based on ultrasonic velocity, characterized in that: An automatic detection device for MB value of machine-made sand based on ultrasonic velocity, applied to any one of claims 1 to 6, comprising: S1: Collect phase signals of distilled water, machine-made sand water solution and methylene blue solutions of different concentrations under the same ultrasonic velocity test at different ambient temperatures, and construct a concentration-time difference model of methylene blue solution under different temperature environments; S2: adding a preset volume of standard methylene blue solution to the machine-made sand aqueous solution of the machine-made sand to be tested, to obtain the supernatant to be tested; collecting phase signals of distilled water, machine-made sand aqueous solution and supernatant to be tested under the same ultrasonic velocity test conditions at the current ambient temperature; adding methylene blue solution to the machine-made sand aqueous solution, stirring and filtering fully, to obtain the supernatant to be tested; S3: according to the current ambient temperature, phase signal and corresponding methylene blue solution concentration-time difference model collected in S2, the concentration of the adsorbed methylene blue solution in the supernatant to be tested is calculated by interpolation method; S4: Calculate the MB value of the machine-made sand to be tested according to the concentration of the methylene blue solution after adsorption.

8. The method for automatic detection of MB value of machine-made sand based on ultrasonic velocity according to claim 7 is characterized in that: The phase difference is calculated according to the three phase signals, and the actual time difference of the ultrasonic transmission process of the methylene blue solution is calculated by using the phase difference. A three-dimensional curve is constructed according to the actual time difference and the corresponding ambient temperature and the concentration of the methylene blue solution to obtain a methylene blue solution concentration-time difference model; in, represents the phase signal of methylene blue solution, Represents the phase signal of the machine-made sand water solution, represents the phase signal of distilled water; It represents the phase difference of ultrasonic wave transmitted in distilled water. It represents the phase difference of ultrasonic wave in the machine-made sand aqueous solution and distilled water. It represents the phase difference of ultrasonic wave transmitted in methylene blue solution and distilled water; Δt=(t3-t1)-(t2-t1) Δt represents the actual time difference; t1 is the time difference of ultrasonic wave transmission in distilled water when calibrating the zero-point concentration of distilled water, and the device takes 0 after calibration; t2 is the time difference of ultrasonic wave transmission in the machine-made sand aqueous solution and distilled water; t3 is the time difference of ultrasonic wave transmission in the methylene blue solution and distilled water.

9. The method for automatic detection of MB value of machine-made sand based on ultrasonic velocity according to claim 8 is characterized in that: In S3, the expression for calculating the concentration of the methylene blue solution after adsorption by interpolation method based on the methylene blue solution concentration-time difference model is: x i <x fina <x i+1 Among them, x fina is the concentration of methylene blue solution after adsorption in the supernatant to be tested; t1′ represents the time difference of ultrasonic wave transmission in distilled water; t2′ represents the time difference of ultrasonic wave transmission in the machine-made sand aqueous solution and distilled water; t3′ represents the time difference of ultrasonic wave transmission in the supernatant to be tested and distilled water; ξ1 represents the temperature coefficient; T represents the current ambient temperature; Δt i Indicates the lower limit of the actual time difference in the methylene blue solution concentration-time difference model corresponding to the supernatant to be tested; Δt i+1 Indicates the actual time difference upper limit in the methylene blue solution concentration-time difference model corresponding to the supernatant to be tested; x i Indicates the concentration of methylene blue solution corresponding to the lower limit of the actual time difference; x i+1 Indicates the concentration of methylene blue solution corresponding to the upper limit of the actual time difference; T i Indicates the ambient temperature corresponding to the lower limit of the actual time difference; T i+1 Indicates the ambient temperature corresponding to the upper limit of the actual time difference.

10. The method for automatic detection of MB value of machine-made sand based on ultrasonic velocity according to claim 7, characterized in that: The expression for calculating the MB value of the machine-made sand to be tested according to the concentration of methylene blue solution after adsorption is: Among them, x fina represents the concentration of methylene blue solution after adsorption; a represents the preset volume; C represents the standard methylene blue solution concentration; b represents the volume of the machine-made sand aqueous solution; c represents the weight of the machine-made sand to be tested used to prepare the machine-made sand aqueous solution in S2.

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