Dynamic phased detection method for residual amount of flocculant in overflow return water of filling thickener

Abstract

The present application provides a dynamic phased detection method for the residual amount of flocculant in the overflow return water of a filling thickener, belonging to the field of tailings filling. The present application adopts a phased detection strategy. For different concentrations of residual flocculant, different methods are used as the feedback methods for the residual amount of flocculant. When the residual amount of flocculant in the overflow return water is high, the viscosity is detected by a rheometer, and the flocculant concentration is inversely deduced using a fitting formula. When the residual amount of flocculant in the overflow return water is low, sedimentation detection (sedimentation time) is mainly used, the slurry mixing sedimentation method is introduced, and combined with a sedimentation rate detection device, the residual amount of flocculant is determined by comparing with a standard fitting curve, solving the defect of insufficient sensitivity of the light transmittance method in the prior art. By dynamically switching the detection mode, the present invention solves the compatibility problem of high and low concentration detection in the prior art, and significantly improves the detection range and accuracy.

Description

Technical Field

[0001] The present invention relates to the technical field of tailings filling, and particularly relates to a dynamic staged detection method for the residual amount of flocculant in the overflow return water of a filling thickener. Background Art

[0002] In the mine filling process, as the core equipment for solid-liquid separation, the thickener accelerates the sedimentation of tailing slurry through flocculants to achieve the preparation of high-concentration underflow and the clarification of overflow water. However, the residual flocculant in the overflow return water has a negative impact on the flotation process, and a large amount of residual flocculant entering the circulating water system will interfere with the flotation effect. For example, the flocculant addition amount in the tailings concentration of Daye Iron Mine was reduced from 40 g / t to 15 g / t, and the copper concentrate recovery rate was restored from 82.54% to 84.35%. Therefore, it is very necessary to detect the residual amount of flocculant in the overflow return water of the filling thickener.

[0003] The patent with the publication number CN 111157403 B discloses a detection method for flocculant in sand. First, water is added to the sand and left stationary to obtain the supernatant, and then it is mixed with cement to obtain cement paste. By comparing the viscosities of the supernatant cement paste and the ordinary water cement paste, the flocculant content is reflected. This method first dries the sand and then prepares the cement paste. The test process is complex and the drying process will cause the activity of the flocculant to decrease, thus affecting the final detection result.

[0004] The patent with the publication number CN 113720804 B discloses a rapid detection method for the residual amount of flocculant in sand for concrete. By preparing a certain amount of flocculant solution with flocculant and then adding bentonite, the transmittance of the suspension with different flocculant contents is compared to reflect whether the residual amount of flocculant exceeds the standard.

[0005] The patent with the publication number CN 116577278 B discloses a detection method for the content of flocculant in sand and its detection device. By preparing a sand and gravel solution from the sand, precipitating it after high-speed stirring, and then recording the start time of the laser emitter and the trigger time of the photosensitive module to reflect the flocculant content.

[0006] The solutions of the aforementioned two inventions all have the following problems: (1) It is difficult to detect the residual content of high-concentration flocculant using a single set of laser induction; (2) When the residual concentration of the flocculant is extremely low, the amount of flocs generated is small and has little impact on the transmittance. At this time, it is difficult to use a single set of laser induction to detect the flocculant content; (3) This method can only be used as a qualitative detection means, but cannot accurately detect the flocculant content.

[0007] In view of this, it is necessary to design a dynamic staged detection method for the residual amount of flocculant in the overflow return water of a filling thickener to solve the above problems. Summary of the Invention

[0008] In view of the technical problems existing in the background art, the present application provides a dynamic staged detection method for the residual amount of flocculant in the overflow return water of a filling thickener. When the content of flocculant in the return water is high, the viscosity is used to feedback the residual amount of flocculant; when the content of flocculant in the return water is low, the flocculation settlement rate or settlement amount is detected by a settlement velocity detection device to judge the residual amount of flocculant.

[0009] The present application provides a dynamic staged detection method for the residual amount of flocculant in the overflow return water of a filling thickener, including the following steps:

[0010] S1, use the flocculant to prepare at least 10 groups of standard solutions of flocculant with different concentrations;

[0011] S2, under the condition of a temperature of 25 °C, use a rheometer to detect the viscosities of the standard solutions with different concentrations, and determine the relationship formula between the viscosity and concentration of the flocculant standard solution by fitting the standard solutions. The relationship formula is divided into a low-concentration relationship formula and a high-concentration relationship formula;

[0012] S3, use a rheometer to detect the viscosity of the return water to be measured. When the measured viscosity ≥ 7.8 mPa·s, use the high-concentration relationship formula to obtain the concentration of the corresponding flocculant. When the obtained concentration of the flocculant is greater than 0.001%, the concentration of the flocculant is the residual amount of flocculant in the return water, and the detection ends; when the obtained concentration of the flocculant is less than or equal to 0.001%, perform a settlement detection on the return water;

[0013] When the measured viscosity < 7.8 mPa·s, use the low-concentration relationship formula to obtain the concentration of the corresponding flocculant. When the obtained concentration of the flocculant is greater than 0.001%, the concentration of the flocculant is the residual amount of flocculant in the return water, and the detection ends; when the obtained concentration of the flocculant is less than or equal to 0.001%, perform a settlement detection on the return water;

[0014] S4, settlement detection: use the flocculant to prepare at least 8 groups of standard solutions with different concentrations; respectively mix the prepared standard solutions with different concentrations with the slurry, use a settlement velocity detection device to detect the settlement velocities of the standard solutions with different concentrations, draw the settlement time curves of the standard solutions with different concentrations according to the relationship between the concentration and the settlement velocity, and fit the settlement time curves of the standard solutions with different concentrations to obtain a standard settlement curve;

[0015] S5, mix the return water to be measured with the slurry, use a settlement velocity detection device to detect its settlement velocity and draw the settlement time curve of the return water to be measured, and substitute the data of the settlement time curve of the return water to be measured into the standard settlement curve obtained in step S4 to obtain the residual concentration of the return water to be measured, which is the residual amount of flocculant, and the detection ends;

[0016] S6. When the sedimentation time for sedimentation detection exceeds 30 min, a high-speed camera is used to record the floc size and quantity, and the residual amount of the flocculant is estimated by comparing with the floc size and quantity of the standard flocculant solution.

[0017] As a further improvement of this application, the flocculant is an anionic polyacrylamide with a molecular weight of 18 million; the high-concentration relationship formula is: η = 9.29 * 10 6 * x 3.14 (1)

[0018] The low-concentration relationship formula is: η = 1975 * x 1.23 + 0.89 (2)

[0019] where x is the concentration; η is the viscosity; the coefficient of determination R of formula (1) 2 ≈ 0.9816 ≥ 0.9, and the coefficient of determination R of formula (2) 2 ≈ 0.9722 ≥ 0.9.

[0020] As a further improvement of this application, in step S1, the concentration range of the flocculant standard solution is 0.001% - 0.1%.

[0021] As a further improvement of this application, in step S4, the concentration range of the standard solution is 0.00001% - 0.001%.

[0022] As a further improvement of this application, in step S4, when the standard solution is mixed with the slurry, the mass ratio of the standard solution to the slurry is (7 - 5):(3 - 5).

[0023] As a further improvement of this application, the method for making the slurry is to sample and dry the tailings from the feed of the filling thickener, then screen the dried tailings, take the -400 mesh tailings with a mass fraction of 50% - 70% and the -200 mesh tailings with a mass fraction of 50% - 30%, and configure them with water into a slurry with a concentration of 10 - 30%.

[0024] As a further improvement of this application, the sedimentation velocity detection device includes a sedimentation tank body, a slurry inlet mixing device, a two-way micro air pump, multiple groups of sedimentation sensors arranged on both sides of the sedimentation tank body, a third electric valve arranged at the output end of the sedimentation tank body, and a high-speed camera; a first electric valve is arranged at the connection between the output end of the slurry inlet mixing device and the sedimentation tank body, and a second electric valve is arranged at the connection between the output end of the two-way micro air pump and the sedimentation tank body; the slurry inlet mixing device has a first feed pipe and a second feed pipe arranged in a Y shape.

[0025] As a further improvement of the present application, the settlement inductor includes a first group of settlement inductors, a second group of settlement inductors, a third group of settlement inductors, and a fourth group of settlement inductors arranged in sequence from top to bottom; when the detection starts, the first electric valve opens, the third electric valve closes, and the second electric valve opens. The settlement flocculant standard solution or return water enters through the first feed pipe of the slurry mixing device, and the prepared slurry enters through the second feed pipe. After the two are gathered, they quickly enter the settlement tank through the pipe mixer of the slurry mixing device, and the inside of the settlement tank is quickly filled; when the first group of settlement inductors senses the slurry liquid level, the first electric valve and the second electric valve close, and the settlement starts; the first group of settlement inductors, the second group of settlement inductors, the third group of settlement inductors, and the fourth group of settlement inductors feedback the settlement liquid level drop times in four stages A, B, C, and D. The settlement curve is drawn through the drop time. By comparing and fitting the return water settlement curve with the flocculant standard settlement curve, when the coefficient of determination R 2 ≥0.9, the flocculant concentration is fed back.

[0026] As a further improvement of the present application, during the feeding process, the two-way micro air pump is turned on to suck air to create a negative pressure condition for the settlement tank, accelerating the mixed slurry to enter the settlement tank; after the settlement process is completed, the second electric valve and the third electric valve open, and the two-way micro air pump is turned on to exhaust air to create a positive pressure for the settlement tank, accelerating the discharge of the slurry in the tank through the sand discharge pipe.

[0027] As a further improvement of the present application, when using a rheometer for detection, the shear rate range of the rheometer is ≤10s -1 .

[0028] The beneficial effects of the present application are as follows:

[0029] (1) The present application provides a dynamic staged detection method for the residual amount of flocculant in the overflow return water in a filling thickener. The present application adopts a staged detection strategy and uses different methods as the feedback method for the residual amount of flocculant for different residual amounts of flocculant concentrations. When the residual amount of flocculant in the overflow return water is relatively high, the viscosity is detected by a rheometer, and the flocculant concentration is inversely deduced using a fitting formula; when the residual amount of flocculant in the overflow return water is low, the settlement effect (settlement time) is mainly used, and the residual amount of flocculant is determined by comparing with the standard fitting curve.

[0030] (2) The present invention significantly improves the detection range and accuracy by dynamically switching the detection mode. The mud mixing settlement method is introduced at low concentrations, combined with the settlement rate detection equipment, solving the defect of insufficient sensitivity of the light transmittance method and solving the compatibility problem of high and low concentration detection in the prior art.

[0031] (3) In view of the extremely low residual amount of the flocculant in the overflow return water in the present invention, a high-speed camera is used to identify the sedimentation amount of the bottom flocs, and then by comparing it with the sedimentation amount obtained from the mixture of the standard flocculant solution and the muddy water, the residual amount of the flocculant in the return water is fed back.

[0032] The above description is only an overview of the technical solution of this application. In order to be able to understand the technical means of this application more clearly, it can be implemented according to the content of the description. And in order to make the above and other purposes, features and advantages of this application more obvious and understandable, the specific embodiments of this application are specifically given below. Brief Description of the Drawings

[0033] In order to more clearly illustrate the technical solution of this application, the drawings used in this application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0034] Figure 1 It is a flowchart of the dynamic phased detection method for the residual amount of the flocculant in the overflow return water in the thickener filled in the embodiment of this application.

[0035] Figure 2 It is a structural schematic diagram of the sedimentation velocity detection device in this application.

[0036] Figure 3 It is the sedimentation curve of the standard flocculant with a concentration of 0.00001%.

[0037] Figure 4 It is the sedimentation curve of the standard flocculant with a concentration of 0.00005%.

[0038] Figure 5 It is the sedimentation curve of the standard flocculant with a concentration of 0.0001%.

[0039] Figure 6 It is the sedimentation curve of the standard flocculant with a concentration of 0.0002%.

[0040] Figure 7 It is the sedimentation curve of the standard flocculant with a concentration of 0.0004%.

[0041] Figure 8 It is the sedimentation curve of the standard flocculant with a concentration of 0.0006%.

[0042] Figure 9 It is the sedimentation curve of the standard flocculant with a concentration of 0.0008%.

[0043] Figure 10 It is the sedimentation curve of the standard flocculant with a concentration of 0.001%.

[0044] Figure 11 It is the sedimentation time rate curve of the standard flocculant.

[0045] Figure 12 It is the sedimentation curve of the backwater of the filling overflow. Specific embodiments

[0046] The embodiments of the technical solution of the present application will be described in detail below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, so they are only examples and cannot be used to limit the protection scope of the present application.

[0047] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above drawings are intended to cover non-exclusive inclusion.

[0048] Referring to "embodiments" herein means that the specific features, structures or characteristics described in connection with the embodiments may be included in at least one embodiment of this application. The phrase appears in various places in the specification and does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0049] The residual flocculant in the backwater of the filling thickener overflow will affect flotation during the water circulation process in the concentrator, affecting the concentrate recovery rate. Existing technologies mostly focus on detecting flocculants in sand, and the methods have certain limitations and are difficult to accurately detect the flocculant content. There is even less research on flocculant detection in the field of filling water treatment.

[0050] This application provides a dynamic staged detection method for the residual amount of flocculant in the backwater of the overflow of a filling thickener. It adopts a staged detection strategy and uses different methods as the feedback method for the residual amount of flocculant for different concentrations of residual flocculant. When the residual amount of flocculant in the backwater of the overflow is high, the viscosity is detected by a rheometer, and the flocculant concentration is inversely deduced using a fitting formula; when the residual amount of flocculant in the backwater of the overflow is low, the sedimentation effect (sedimentation time) is mainly used, and the residual amount of flocculant is determined by comparing with the standard fitting curve.

[0051] Please refer to Figure 1 , the embodiments of this application provide a dynamic staged detection method for the residual amount of flocculant in the backwater of the overflow of a filling thickener, including the following steps:

[0052] S1, using a flocculant to prepare at least 10 groups of flocculant standard solutions with different concentrations;

[0053] Among them, the concentration range of the flocculant standard solution is 0.001% - 0.1%. Preferably, it is 0.001%, 0.003%, 0.005%, 0.008%, 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.08%, 0.1%.

[0054] The flocculant is an anionic polyacrylamide with a molecular weight of 18 million.

[0055] S2. Under the condition of a temperature of 25 °C, use a rheometer to detect the viscosity of standard solutions with different concentrations, and determine the relationship formula between the viscosity and concentration of the flocculant standard solution through fitting of the standard solutions. The relationship formula is divided into a low-concentration relationship formula and a high-concentration relationship formula;

[0056] The high-concentration relationship formula is: η = 9.29 * 10 6 * x 3.14 (R² ≈ 0.9816 ≥ 0.9); (1)

[0057] The low-concentration relationship formula is: η = 1975 * x 1.23 + 0.89 (R² ≈ 0.9722 ≥ 0.9); (2)

[0058] Among them, x is the concentration; η is the viscosity;

[0059] When using a rheometer for detection, the shear rate range of the rheometer is ≤ 10 s -1 .

[0060] S3. Use a rheometer to detect the viscosity of the return water to be tested. When the measured viscosity ≥ 7.8 mPa·s, use formula (1) to obtain the corresponding concentration of the flocculant. When the obtained concentration of the flocculant is greater than 0.001%, the concentration of the flocculant is the residual amount of the flocculant in the return water, and the detection ends; when the obtained concentration of the flocculant is less than or equal to 0.001%, conduct a sedimentation test on the return water;

[0061] When the measured viscosity < 7.8 mPa·s, use formula (2) to obtain the corresponding concentration of the flocculant. When the obtained concentration of the flocculant is greater than 0.001%, the concentration of the flocculant is the residual amount of the flocculant in the return water, and the detection ends; when the obtained concentration of the flocculant is less than or equal to 0.001%, conduct a sedimentation test on the return water;

[0062] In the viscosity detection, as the concentration increases, the interaction between polyacrylamide molecules in the solution enhances, and the entanglement degree intensifies. Therefore, it is divided into two formulas for low concentration and high concentration, which are determined through fitting experiments of standard solutions. Use the formula to inversely calculate the content of the flocculant in the return water. When the calculated content of the flocculant in the return water is less than or equal to 0.001%, then conduct subsequent sedimentation detection.

[0063] S4, sedimentation detection: using flocculants to prepare at least 8 groups of standard solutions with different concentrations; respectively mixing the prepared standard solutions with different concentrations with mud, using sedimentation velocity detection equipment to detect the sedimentation velocity of the standard solutions with different concentrations, drawing sedimentation time curves of the standard solutions with different concentrations according to the relationship between concentration and sedimentation velocity, and fitting the sedimentation time curves of the standard solutions with different concentrations to obtain standard sedimentation curves;

[0064] The concentration range of the standard solution is 0.00001%-0.001%, preferably 0.00001%, 0.00005%, 0.0001%, 0.0002%, 0.0004%, 0.0006%, 0.0008%, 0.001%.

[0065] Among them, when the standard solution is mixed with the mud, the mass ratio of the standard solution to the mud is (7~5): (3~5).

[0066] The method for making mud is to sample and dry the tailings fed to the filling thickener, and then screen the dried tailings to take 50%~70% of the -400 mesh tailings and 50%~30% of the -200 mesh tailings, and mix them with water to form a mud with a concentration of 10~30%. A higher proportion of fine particles can better reflect different sedimentation effects.

[0067] S5, mixing the return water to be tested with the mud, using a sedimentation velocity detection device to detect the sedimentation velocity and drawing a sedimentation time curve of the return water to be tested, substituting the data of the sedimentation time curve of the return water to be tested into the standard sedimentation curve obtained in step S4, and obtaining the residual concentration of the return water to be tested, which is the residual amount of the flocculant, and the detection is completed;

[0068] S6. When the sedimentation rate is too slow and the sedimentation time of the sedimentation test exceeds 30 minutes (the residual flocculant is extremely low), use a high-speed camera to record the floc size and number, and compare them with the floc size and number of the standard flocculant solution to estimate the residual flocculant.

[0069] Specifically, a high-speed camera 10 is arranged at the bottom of the sedimentation velocity detection equipment. When the flocculant dosage is less than or equal to 0.00001%, the mixed slurry is difficult to settle and only a small amount of flocs can be generated. At this time, the size and amount of flocs are recorded and counted by the high-speed camera 10. The flocculant content in the return water is determined by comparing the flocculant situation of the flocculant standard solution with the flocculant situation of the return water.

[0070] See also Figure 2As shown in the figure, the sedimentation velocity detection device includes a sedimentation tank body 7, a slurry feeding and mixing device, a two-way micro air pump 5, multiple groups of sedimentation sensors arranged on both sides of the sedimentation tank body 7, a third electric valve 11 arranged at the output end of the sedimentation tank body 7, and a high-speed camera 10.

[0071] Among them, a first electric valve 4 is arranged at the connection between the output end of the slurry feeding and mixing device and the sedimentation tank body 7. The slurry feeding and mixing device has a first feeding pipeline 1 and a second feeding pipeline 2 arranged in a Y shape.

[0072] A second electric valve 6 is arranged at the connection between the output end of the two-way micro air pump 5 and the sedimentation tank body 7.

[0073] The sedimentation sensors include a first group of sedimentation sensors (sensor 8-1 and sensor 9-1), a second group of sedimentation sensors (sensor 8-2 and sensor 9-2), a third group of sedimentation sensors (sensor 8-3 and sensor 9-3), and a fourth group of sedimentation sensors (sensor 8-4 and sensor 9-4) arranged from top to bottom in sequence.

[0074] When the detection starts, the first electric valve 4 is opened, the third electric valve 11 is closed, and the second electric valve 6 is opened. The sedimentation flocculant standard solution or return water enters through the first feeding pipeline 1 of the slurry feeding and mixing device, and the prepared slurry enters through the second feeding pipeline 2. After the two are gathered, they quickly enter the sedimentation tank body 7 through the pipeline mixer 3 of the slurry feeding and mixing device. The inside of the sedimentation tank body 7 is quickly filled. When the first group of sedimentation sensors (sensor 8-1 and sensor 9-1) sense the slurry liquid level, the first electric valve 4 and the second electric valve 6 are closed, and the sedimentation starts; the sedimentation liquid level drop times in four stages A, B, C, and D are fed back through the first group of sedimentation sensors, the second group of sedimentation sensors, the third group of sedimentation sensors, and the fourth group of sedimentation sensors. The sedimentation curve is drawn through the drop time. By comparing and fitting the return water sedimentation curve with the flocculant standard sedimentation curve, when the determination coefficient R 2 ≥0.9, the flocculant concentration is fed back.

[0075] Among them, during the feeding process, the two-way micro air pump 5 rotates forward to start suction to form a negative pressure condition for the sedimentation tank body 7, accelerating the mixed slurry to enter the sedimentation tank body 7.

[0076] After the sedimentation process is completed, the second electric valve 6 and the third electric valve 11 are opened, and the two-way micro air pump 5 rotates in reverse to start exhausting to form a positive pressure for the sedimentation tank body 7, accelerating the discharge of the slurry in the tank through the sand discharge pipe 12.

[0077] Furthermore, the bottom of the sedimentation tank body 7 is of a conical structure with a cone angle of 20°-45°, which is beneficial to the discharge of the slurry in the tank.

[0078] Some specific embodiments are listed below. It should be noted that the embodiments described below are exemplary and are only used to explain the present application, and should not be construed as a limitation to the present application. For those without specific technologies or conditions indicated in the embodiments, the technologies or conditions described in the literature in this field or according to the product specifications are followed. For the reagents or instruments without the manufacturer indicated, they are all conventional products that can be obtained through commercial purchases.

[0079] Embodiment 1

[0080] This embodiment provides a dynamic staged detection method for the residual amount of flocculant in the overflow return water of a filling thickener. Taking the overflow water of a filling thickener as the object and using an anionic polyacrylamide X with a molecular weight of 18 million as the flocculant, the specific steps are as follows:

[0081] (a) Prepare 12 groups of standard solutions with concentrations of 0, 0.001%, 0.003%, 0.005%, 0.008%, 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.08%, and 0.1% using flocculant X;

[0082] (b) Under the condition of a temperature of 25 °C, use a rheometer to detect the viscosities of the 12 groups of standard solutions in step (a) (the data is shown in Table 1). Determine the relationship formula between the viscosity and concentration of the flocculant standard solution through the data fitting of the 12 groups of standard solutions. The relationship formula is divided into a low-concentration relationship formula and a high-concentration relationship formula.

[0083] Specifically, substitute the data in Table 1 (serial numbers 0-5) into the low-concentration relationship formula model η = A * x B + C, and substitute the data in Table 1 (serial numbers 6-11) into the high-concentration relationship formula model η = E * x F , and obtain the low-concentration relationship formula and the high-concentration relationship formula respectively;

[0084] The low-concentration formula is: η = 1975 * x 1.23 + 0.89;

[0085] The high-concentration formula is: η = 9.29 * 10 6 * x 3.14 .

[0086] Among them, x is the concentration; η is the viscosity;

[0087] The coefficient of determination R ² is an important index used to measure the fitting degree of the model to the data in regression analysis. The closer the R ² value is to 1, the better the fitting effect of the model to the data.

[0088] The calculation formula for the coefficient of determination in the non-linear model is: R² = 1 - SSE / SST,

[0089] SSE is the total sum of squared residuals, and its calculation formula is:

[0090]

[0091] Where: — The actual experimental value;

[0092] — The calculated value of the fitting formula

[0093] SST is the total sum of squared deviations, and its calculation formula is:

[0094]

[0095] Where: — The actual experimental value;

[0096] — The actual average value of the experiment;

[0097] Combining the data in Table 1 (Serial numbers 0 - 5) with the low-concentration relationship formula η = 1975 * x 1.23 + 0.89; substituting and obtaining the following data:

[0098] SST = 44.97

[0099] SSE = 1.25

[0100] R 2 = 1 - 1.25 / 44.97 = 0.9722

[0101] The coefficient of determination R ² ≈ 0.9722 ≥ 0.9, indicating that the model has a good fitting effect on the data;

[0102] That is, the low-concentration relationship formula is: η = 1975 * x 1.23 + 0.89 (R² ≈ 0.9722 ≥ 0.9).

[0103] Combining the data in Table 1 (Serial numbers 6 - 11) with the high-concentration relationship formula η = 9.29 * 10 6 *x 3.14 ; substituting and obtaining the following data:

[0104] SST = 52282538.98

[0105] SSE = 961242.57

[0106] R 2 = 1 - 961242.57 / 52282538.98 = 0.9816

[0107] The coefficient of determination of this formula is R²≈0.9816≥0.9, which indicates that the model fits the data well;

[0108] That is, the high concentration relationship formula is: η=9.29*10 6 *x 3.14 (R²≈0.9816≥0.9).

[0109] (c) Use a rheometer to detect the return water at a shear rate of 10s -1 When the viscosity is 0.95 mPa·s (0.95≤7.8 mPa·s belongs to the low concentration range), the concentration is 0.000377% by using the low concentration formula. This concentration value is less than 0.001%, and the return water needs to be tested for sedimentation.

[0110] (d) Use flocculant X to prepare 8 sets of standard solutions with concentrations of 0.00001%, 0.00005%, 0.0001%, 0.0002%, 0.0004%, 0.0006%, 0.0008% and 0.001%;

[0111] (e) -400 mesh 70%, -200 mesh 30%, and mud powder are prepared into mud with a water content of 20%. The 8 groups of standard solutions in step (d) are respectively mixed with mud in a ratio of 1:1 and enter the sedimentation velocity detection equipment through the first feeding pipe 1 and the second feeding pipe 2.

[0112] (f) When the detection starts, the first electric valve 4 opens, the third electric valve 11 closes, and the second electric valve 6 opens. A standard solution of sedimentation flocculant with a concentration of 0.00001% enters through the first feed pipe 1, and the prepared mud enters through the second feed pipe 2. After the two are combined, they quickly enter the sedimentation tank 7 through the slurry mixing device pipeline mixer 3. The interior of the sedimentation tank 7 is quickly filled. When the sensor 8-1 and the sensor 9-1 sense the mud liquid level, the first electric valve 4 and the second electric valve 6 are closed, and sedimentation begins.

[0113] The four sets of sensors are used to feedback the falling time of the sedimentation liquid level in the four stages A, B, C, and D. The sedimentation curve of the sedimentation flocculant standard solution with a concentration of 0.00001% is drawn according to the falling speed, such as Figure 3 After the sedimentation process is completed, the second electric valve 6 and the third electric valve 11 are opened, and the two-way micro air pump 5 is reversed and opened to exhaust gas to form a positive pressure for the sedimentation tank 7, accelerating the discharge of the slurry in the tank through the sand discharge pipe 12;

[0114] (g) Repeat steps (e) and (f) with the remaining 7 sets of standard flocculant solutions to draw the sedimentation curves of the 7 sets of standard flocculant solutions, such as Figures 4 - 10As shown; the sedimentation curves of the aforementioned 8 groups of flocculant standard solutions with different concentrations are fitted to obtain a standard sedimentation curve, as Figure 11 shown;

[0115] (h) Use the backfill overflow return water to be tested and repeat steps (e) and (f) to draw its sedimentation curve, as Figure 12 shown. Substitute the data in the figure into the standard sedimentation curve obtained in step (g), and the residual concentration of the backfill flocculant is 0.00001569%.

[0116] Verification: Take the backfill overflow return water to be tested, and use high performance liquid chromatography (HPLC) to measure that the residual content of the flocculant in the return water is 0.15 mg / L, which is basically consistent with the test result of Example 1 of this application.

[0117] Table 1 Concentration and Viscosity of Polyacrylamide Solution

[0118]

[0119] Example 2:

[0120] In this example, a kind of backfill thickener overflow water is taken as the object, and the flocculant used is anionic polyacrylamide X with a molecular weight of 18 million. In this example, the flocculant is continuously added to the return water, and the addition amount is 0.07%.

[0121] Repeat steps (a), (b), and (c) of Example 1 to obtain the viscosity of the return water to be tested as 2350 mPa·s, and this value ≥ 7.8 mPa·s. Using the high-concentration formula and back-calculating from the viscosity, the flocculant concentration is about 0.0713% > 0.001%. Then, the flocculant concentration is the residual amount of the flocculant in the return water to be tested, which is 0.0713%.

[0122] Verification: Use high performance liquid chromatography (HPLC) to measure that the residual content of the flocculant in the return water to be tested is 705 mg / L, which is basically consistent with the test result of Example 2 of this application.

[0123] It should be noted that this application is not limited to the above embodiments. The above embodiments are only examples, and embodiments with the same composition and the same function and effect as the technical idea within the technical solution scope of this application are all included in the technical scope of this application. In addition, within the scope of not departing from the main idea of this application, various deformations that those skilled in the art can think of are applied to the embodiments, and other ways constructed by combining some constituent elements in the embodiments are also included in the scope of this application.

Claims

1. A dynamic staged detection method for the residual amount of flocculant in overflow return water from a filling thickener, characterized in that: The following steps are involved: S1, using flocculants to prepare at least 10 groups of flocculant standard solutions with different concentrations; S2, under the condition of temperature 25℃, use rheometer to detect the viscosity of standard solutions of different concentrations, and determine the relationship formula between viscosity and concentration of flocculant standard solution by standard solution fitting. The relationship formula is divided into low concentration relationship formula and high concentration relationship formula; S3, using a rheometer to detect the viscosity of the return water to be tested. When the measured viscosity is ≥7.8 mPa·s, the high concentration relationship formula is used to obtain the corresponding flocculant concentration. When the obtained flocculant concentration is greater than 0.001%, the flocculant concentration is the residual amount of flocculant in the return water, and the test is completed; when the obtained flocculant concentration is less than or equal to 0.001%, the return water is subjected to sedimentation test; When the measured viscosity is less than 7.8 mPa·s, the low concentration relationship formula is used to obtain the corresponding flocculant concentration. When the obtained flocculant concentration is greater than 0.001%, the flocculant concentration is the residual amount of flocculant in the return water, and the test ends. When the obtained flocculant concentration is less than or equal to 0.001%, the return water is subjected to sedimentation test. S4, sedimentation detection: using flocculants to prepare at least 8 groups of standard solutions with different concentrations; respectively mixing the prepared standard solutions with different concentrations with mud, using sedimentation velocity detection equipment to detect the sedimentation velocity of the standard solutions with different concentrations, drawing sedimentation time curves of the standard solutions with different concentrations according to the relationship between concentration and sedimentation velocity, and fitting the sedimentation time curves of the standard solutions with different concentrations to obtain standard sedimentation curves; S5, mixing the return water to be tested with the mud, using a sedimentation velocity detection device to detect the sedimentation velocity and drawing a sedimentation time curve of the return water to be tested, substituting the data of the sedimentation time curve of the return water to be tested into the standard sedimentation curve obtained in step S4, and obtaining the residual concentration of the return water to be tested, which is the residual amount of the flocculant, and the detection is completed; S6. When the sedimentation time of the sedimentation test exceeds 30 minutes, use a high-speed camera to record the floc size and number, and compare them with the floc size and number of the standard flocculant solution to estimate the flocculant residue.

2. The dynamic staged detection method for the residual amount of flocculant in the overflow return water of the filling thickener according to claim 1 is characterized in that: The flocculant is an anionic polyacrylamide with a molecular weight of 18 million; the high concentration relationship formula is: η=9.29*10 6 * x 3.14 The low concentration relationship formula is: η = 1975* x 1.23 +0.89 Where x is the concentration; η is the viscosity; the coefficient of determination R of the high concentration relationship formula 2 ≈0.9816≥0.9, the determination coefficient R of the low concentration relationship formula 2 ≈0.9722≥0.

9.

3. The dynamic staged detection method for the residual amount of flocculant in the overflow return water of the filling thickener according to claim 1 is characterized in that: In step S1, the concentration range of the flocculant standard solution is 0.001%-0.1%.

4. The method for dynamic phased detection of residual flocculant in overflow return water of a filling thickener according to claim 1, characterized in that: In step S4, the concentration range of the standard solution is 0.00001%-0.001%.

5. The method for dynamic phased detection of residual flocculant in overflow return water of a filling thickener according to claim 1, characterized in that: In step S4, when the standard solution is mixed with the mud, the mass ratio of the standard solution to the mud is (7~5):(3~5).

6. The method for dynamic phased detection of residual flocculant in overflow return water of a filling thickener according to claim 5, characterized in that: The method for preparing the mud is to sample and dry the tailings fed to the filling thickener, then screen the dried tailings, take 50% to 70% of the -400 mesh tailings and 50% to 30% of the -200 mesh tailings by mass fraction, and mix them with water to form a mud with a concentration of 10 to 30%.

7. The method for dynamic phased detection of residual flocculant in overflow return water of a filling thickener according to claim 1, characterized in that: The sedimentation velocity detection equipment includes a sedimentation tank body, a slurry feeding and mixing device, a two-way micro air pump, a plurality of sedimentation sensors arranged on both sides of the sedimentation tank body, a third electric valve arranged at the output end of the sedimentation tank body, and a high-speed camera; a first electric valve is arranged at the connection between the output end of the slurry feeding and mixing device and the sedimentation tank body, and a second electric valve is arranged at the connection between the output end of the two-way micro air pump and the sedimentation tank body; the slurry feeding and mixing device has a first feed pipe and a second feed pipe arranged in a Y shape.

8. The method for dynamic phased detection of the residual amount of flocculant in overflow return water of a filling thickener according to claim 7, characterized in that: The sedimentation sensor comprises a first set of sedimentation sensors, a second set of sedimentation sensors, a third set of sedimentation sensors, and a fourth set of sedimentation sensors, which are arranged in sequence from top to bottom; when the detection starts, the first electric valve is opened, the third electric valve is closed, and the second electric valve is opened, and the sedimentation flocculant standard solution or return water enters through the first feed pipe of the slurry feeding mixing device, and the configured mud enters through the second feed pipe, and the two are quickly collected and enter the sedimentation tank body through the pipeline mixer of the slurry feeding mixing device, and the interior of the sedimentation tank body is quickly filled; when the first set of sedimentation sensors senses the mud liquid level, the first electric valve and the second electric valve are closed, and sedimentation begins; the sedimentation liquid level drop time of the four stages A, B, C, and D is fed back by the first set of sedimentation sensors, the second set of sedimentation sensors, the third set of sedimentation sensors, and the fourth set of sedimentation sensors, and the sedimentation curve is drawn according to the drop time, and the return water sedimentation curve is compared and fitted with the flocculant standard sedimentation curve, when the determination coefficient R 2 When ≥0.9, the flocculant concentration is fed back.

9. The method for dynamic phased detection of residual flocculant in overflow return water of a filling thickener according to claim 7, characterized in that: During the feeding process, the two-way micro air pump is turned on to inhale air to form a negative pressure condition for the sedimentation tank, thereby accelerating the mixed mud to enter the sedimentation tank; after the sedimentation process is completed, the second electric valve and the third electric valve are opened, and the two-way micro air pump is turned on to exhaust air to form a positive pressure for the sedimentation tank, thereby accelerating the discharge of the slurry in the tank through the sand discharge pipe.

10. The method for dynamic phased detection of the residual amount of flocculant in overflow return water of a filling thickener according to claim 1, characterized in that: When using a rheometer for testing, the shear rate range of the rheometer is ≤10s -1 .

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