Dynamic staged detection method for residual quantity of flocculating agent in overflow return water in filling thickener

Abstract

The invention provides a dynamic staged detection method for the residual quantity of a flocculating agent in overflow return water in a filling thickener, and belongs to the field of tailing filling. According to the method, a staged detection strategy is adopted, different methods are adopted as feedback methods for the residual quantity of the flocculating agent aiming at different residual quantity concentrations of the flocculating agent, and when the residual quantity of the flocculating agent in overflow backwater is relatively high, the viscosity is detected through a rheometer, and the concentration of the flocculating agent is reversely deduced by utilizing a fitting formula. When the residual quantity of the overflow backwater flocculating agent is low, sedimentation detection (sedimentation time) is mainly adopted, a slurry mixing sedimentation method is introduced, sedimentation rate detection equipment is combined, and the residual quantity of the flocculating agent is compared with a standard fitting curve to determine the residual quantity of the flocculating agent, so that the defect of insufficient sensitivity of a light transmittance method in the prior art is overcome. By dynamically switching the detection modes, the compatibility problem of high and low concentration detection in the prior art is solved, and the detection range and precision are remarkably improved.

Description

Technical Field

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

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

[0003] The patent with publication number CN 111157403 B discloses a method for detecting flocculants in sand. First, water is added to the sand to obtain a supernatant liquid, which is then mixed with cement to obtain cement slurry. The viscosity of the supernatant cement slurry and the viscosity of the ordinary water cement slurry are compared to determine the flocculant content. This method first dries the sand and then prepares the cement slurry. The test process is complicated and the drying process will reduce the activity of the flocculant, thus affecting the final test results.

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

[0005] The patent with publication number CN 116577278 B discloses a method and device for detecting the flocculant content in sand. The flocculant content is reflected by preparing sand into a sand and gravel solution, stirring at high speed and then settling, and then recording the start time of the laser transmitter and the trigger time of the photosensitive module.

[0006] The above two inventions have the following problems: (1) It is difficult to detect high-concentration flocculant residual content using a single group of laser sensors; (2) When the flocculant residual concentration is extremely low, the amount of flocs produced is small and has little effect on the transmittance. At this time, it is difficult to use a single group of laser sensors to detect the flocculant content; (3) This method can only be used as a qualitative detection method, 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 the filling thickener to solve the above problems. Summary of the invention

[0008] In view of the technical problems existing in the background technology, 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 flocculant content in the return water is high, the residual amount of flocculant is fed back by viscosity; when the flocculant content in the return water is low, the flocculation sedimentation rate or sedimentation amount is fed back by the sedimentation velocity detection equipment to judge the residual amount of flocculant.

[0009] The present application provides a method for dynamically detecting the residual amount of flocculant in overflow return water of a filling thickener in stages, comprising the following steps: 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.

[0010] As a further improvement of the present 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) The low concentration relationship formula is: η = 1975* x 1.23 +0.89 (2) Where x is the concentration; η is the viscosity; the determination coefficient R of formula (1) 2 ≈0.9816≥0.9, the coefficient of determination R of formula (2) 2 ≈0.9722≥0.9.

[0011] As a further improvement of the present application, in step S1, the concentration range of the flocculant standard solution is 0.001%-0.1%.

[0012] As a further improvement of the present application, in step S4, the concentration range of the standard solution is 0.00001%-0.001%.

[0013] As a further improvement of the present application, 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).

[0014] As a further improvement of the present application, the method for preparing the mud is to sample and dry the tailings that feed 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 with a mass fraction, and mix them with water to form a mud with a concentration of 10~30%.

[0015] As a further improvement of the present application, 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.

[0016] As a further improvement of the present application, the sedimentation sensor comprises a first group of sedimentation sensors, a second group of sedimentation sensors, a third group of sedimentation sensors, and a fourth group 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 standard solution of the sedimentation flocculant or the return water enters through the first feeding pipe of the slurry feeding mixing device, and the configured mud enters through the second feeding 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 group 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 group of sedimentation sensors, the second group of sedimentation sensors, the third group of sedimentation sensors, and the fourth group of sedimentation sensors, and the sedimentation curve is drawn according to the drop time, and by comparing and fitting the return water sedimentation curve with the flocculant standard sedimentation curve, when the determination coefficient R 2 When ≥0.9, the flocculant concentration is fed back.

[0017] As a further improvement of the present application, 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.

[0018] As a further improvement of the present application, when using a rheometer for testing, the shear rate range of the rheometer is ≤10s -1 .

[0019] The beneficial effects of this application are: (1) The present application provides a dynamic staged detection method for the residual amount of flocculant in the overflow return water of a filling thickener. The present application adopts a staged detection strategy, and adopts different methods as the feedback method of the residual amount of flocculant for different residual concentrations 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 inferred by using a fitting formula; when the residual amount of flocculant in the overflow return water is low, the sedimentation effect (sedimentation time) is used as the main factor, and the residual amount of flocculant is determined by comparing it with the standard fitting curve.

[0020] (2) The present invention significantly improves the detection range and accuracy by dynamically switching the detection mode. The mud mixing sedimentation method is introduced at low concentrations, combined with sedimentation rate detection equipment, to solve the defect of insufficient sensitivity of the transmittance method and solve the compatibility problem of high and low concentration detection in the prior art.

[0021] (3) In view of the extremely low residual amount of flocculant in the overflow water, the present invention uses a high-speed camera to identify the amount of flocculent sediment at the bottom, and then compares it with the sediment obtained by mixing a standard flocculant solution with muddy water, thereby providing feedback on the residual amount of flocculant in the return water.

[0022] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solution of the present application, the following is a brief introduction to the drawings used in the present application. Obviously, the drawings described below are only some embodiments of the present application, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0024] Figure 1 This is a flow chart of a dynamic stage-by-stage detection method for the amount of flocculant residue in overflow return water from a filling thickener in an embodiment of the present application.

[0025] Figure 2 It is a structural schematic diagram of the sedimentation velocity detection equipment in this application.

[0026] Figure 3 This is the sedimentation curve of the standard flocculant with a concentration of 0.00001%.

[0027] Figure 4 This is the sedimentation curve of the standard flocculant with a concentration of 0.00005%.

[0028] Figure 5 This is the sedimentation curve of the standard flocculant with a concentration of 0.0001%.

[0029] Figure 6 This is the sedimentation curve of the standard flocculant with a concentration of 0.0002%.

[0030] Figure 7 This is the sedimentation curve of the standard flocculant with a concentration of 0.0004%.

[0031] Figure 8 This is the sedimentation curve of the standard flocculant at a concentration of 0.0006%.

[0032] Fig. 9 This is the sedimentation curve of the standard flocculant at a concentration of 0.0008%.

[0033] Fig.10 This is the sedimentation curve of the standard flocculant at 0.001% concentration.

[0034] Fig.11 It is the settling time rate curve of standard flocculant.

[0035] Fig.12 It is the filling overflow backwater sedimentation curve. DETAILED DESCRIPTION

[0036] The following embodiments of the technical solution of the present application are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0037] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians 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" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0038] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0039] The residual flocculants in the overflow return water of the filling thickener will affect flotation during the water circulation process of the concentrator, affecting the concentrate recovery rate. Existing technologies are mostly focused on the detection of 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.

[0040] The present application provides a dynamic stage-by-stage detection method for the residual amount of flocculant in the overflow return water of a filling thickener. The method adopts a stage-by-stage detection strategy and adopts different methods as feedback methods for the residual amount of flocculant for different residual flocculant concentrations. 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 inferred using a fitting formula. When the residual amount of flocculant in the overflow return water is low, the sedimentation effect (sedimentation time) is used as the main method, and the residual amount of flocculant is determined by comparing it with the standard fitting curve.

[0041] Please refer to Figure 1 The present application provides a method for dynamically detecting the amount of residual flocculant in overflow return water of a filling thickener in stages, comprising the following steps: S1, using flocculants to prepare at least 10 groups of flocculant standard solutions with different concentrations; The concentration range of the flocculant standard solution is 0.001%-0.1%, preferably 0.001%, 0.003%, 0.005%, 0.008%, 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.08%, 0.1%.

[0042] The flocculant is anionic polyacrylamide with a molecular weight of 18 million.

[0043] 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; The high concentration relationship formula is: η=9.29*10 6 * x 3.14 (R²≈0.9816≥0.9); (1) The low concentration relationship formula is: η = 1975* x 1.23 +0.89 (R²≈0.9722≥0.9); (2) Where x is the concentration; η is the viscosity; When using a rheometer for testing, the shear rate range of the rheometer is ≤10s -1 .

[0044] S3, use a rheometer to detect the viscosity of the return water to be tested. When the measured viscosity is ≥7.8 mPa·s, use formula (1) 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%, perform sedimentation test on the return water. When the measured viscosity is less than 7.8 mPa·s, the corresponding flocculant concentration is obtained using formula (2). 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. In the viscosity test, as the concentration increases, the interaction between polyacrylamide molecules in the solution increases, and the degree of entanglement intensifies. Therefore, two formulas, low concentration and high concentration, are used, which are determined by fitting the standard solution experiment. The formula is used to reversely calculate the flocculant content in the return water. When the calculated return water flocculant content is less than or equal to 0.001%, subsequent sedimentation tests are performed.

[0045] 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; 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%.

[0046] 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).

[0047] 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.

[0048] 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 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.

[0049] 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.

[0050] See also Figure 2 As shown, the sedimentation velocity detection equipment includes a sedimentation tank body 7, a slurry feeding and mixing device, a bidirectional micro air pump 5, a plurality 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.

[0051] 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, and the slurry feeding and mixing device has a first feeding pipeline 1 and a second feeding pipeline 2 arranged in a Y shape.

[0052] A second electric valve 6 is provided at the connection between the output end of the bidirectional micro air pump 5 and the sedimentation tank 7 .

[0053] 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) which are arranged in order from top to bottom.

[0054] 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 standard solution of the sedimentation flocculant or the return water enters through the first feed pipe 1 of the slurry mixing device, 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 pipeline mixer 3 of the slurry mixing device. The interior of the sedimentation tank 7 is quickly filled. When the first set of sedimentation sensors (sensor 8-1 and sensor 9-1) sense the mud liquid level, the first electric valve 4 and the second electric valve 6 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 is used to feed back. The sedimentation curve is drawn according to the drop time. By comparing and fitting the return water sedimentation curve with the flocculant standard sedimentation curve, when the determination coefficient R 2 When ≥0.9, the flocculant concentration is fed back.

[0055] During the feeding process, the bidirectional micro air pump 5 rotates forward to start suction to form a negative pressure condition for the sedimentation tank 7, thereby accelerating the mixed mud to enter the sedimentation tank 7.

[0056] 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 turned on 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.

[0057] Furthermore, the bottom of the sedimentation tank 7 is a conical structure with a cone angle of 20°-45°, which is conducive to the discharge of slurry in the tank.

[0058] 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 limiting the present application. If specific techniques or conditions are not specified in the embodiments, the techniques or conditions described in the literature in this area or the product specifications are used. The reagents or instruments used without specifying the manufacturer are all conventional products that can be obtained commercially.

[0059] Example 1 This embodiment provides a dynamic phased detection method for the residual amount of flocculant in overflow return water of a filling thickener, taking overflow water of a filling thickener as the object, and using anionic polyacrylamide X as the flocculant, with a molecular weight of 18 million, and specifically comprising the following steps: (a) Use flocculant X to prepare 12 sets 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%; (b) At a temperature of 25°C, a rheometer was used to detect the viscosity of the 12 groups of standard solutions in step (a) (the data are shown in Table 1). The relationship formula between the viscosity and concentration of the flocculant standard solution was determined by fitting the data of the 12 groups of standard solutions. The relationship formula is divided into a low concentration relationship formula and a high concentration relationship formula.

[0060] Specifically, the data in Table 1 (serial number 0-5) are substituted into the low concentration relationship formula model η=A* x B +C. 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 high concentration relationship formula respectively; The low concentration formula is: η = 1975* x 1.23 +0.89; The high concentration formula is: η=9.29*10 6 *x 3.14 .

[0061] Where x is the concentration; η is the viscosity; Coefficient of determination R ² It is an important indicator used in regression analysis to measure the degree of fit of the model to the data. ² The closer the value is to 1, the better the model fits the data.

[0062] The formula for calculating the coefficient of determination in the nonlinear model is: R²=1-SSE / SST, SSE is the residual total sum of squares, and the calculation formula is: in: —actual test value; —Calculated value of fitting formula SST is the total sum of squares of deviations, and the calculation formula is: in: —actual test value; — Actual average value of the test; Combining the data in Table 1 (serial number 0-5) with the low concentration relationship formula η = 1975* x 1.23 +0.89; Substitute it into the following data: SST=44.97 SSE=1.25 R 2 =1-1.25 / 44.97=0.9722 The coefficient of determination R ² ≈0.9722≥0.9, indicating that the model fits the data well; That is, the low concentration relationship formula is: η = 1975* x 1.23 +0.89 (R²≈0.9722≥0.9).

[0063] Combined with the data in Table 1 (serial number 6-11) and the high concentration relationship formula η=9.29*10 6 *x 3.14 ; Substitute the following data into the result: SST = 52282538.98 SSE = 961242.57 R 2 =1-961242.57 / 52282538.98=0.9816 The coefficient of determination of this formula is R²≈0.9816≥0.9, which indicates that the model fits the data well; That is, the high concentration relationship formula is: η=9.29*10 6 *x 3.14 (R²≈0.9816≥0.9).

[0064] (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.

[0065] (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%; (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.

[0066] (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.

[0067] 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; (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 respectively. Figure 4-10 As shown; the sedimentation curves of the above 8 groups of flocculant standard solutions with different concentrations are fitted to obtain the standard sedimentation curve, as shown in Fig.11 As shown; (h) Repeat steps (e) and (f) using the overflow water to be tested to draw its settlement curve, such as Fig.12 As shown, the data in the figure are substituted into the standard sedimentation curve obtained in step (g), and the residual concentration of the returned water flocculant is 0.00001569%.

[0068] Verification: The overflow return water to be tested was taken and the residual content of flocculant in the return water was measured by high performance liquid chromatography (HPLC) to be 0.15 mg / L, which is basically consistent with the test result of Example 1 of the present application.

[0069] Table 1 Concentration and viscosity of polyacrylamide solution Embodiment 2: This embodiment uses overflow water from a filling thickener as the object, and the flocculant used is anionic polyacrylamide X with a molecular weight of 18 million. In this embodiment, flocculant is continuously added to the return water, and the added amount is 0.07%.

[0070] Repeat steps (a), (b), and (c) of Example 1 to obtain a viscosity of the return water to be measured of 2350 mPa·s, which is ≥7.8 mPa·s. Using the high concentration formula, the flocculant concentration is calculated from the viscosity to be about 0.0713%>0.001%. Therefore, the flocculant concentration is the residual amount of flocculant in the return water to be measured, which is 0.0713%.

[0071] Verification: The residual content of flocculant in the return water to be tested was measured by high performance liquid chromatography (HPLC) and was found to be 705 mg / L, which is basically consistent with the test result of Example 2 of the present application.

[0072] It should be noted that the present application is not limited to the above-mentioned embodiments. The above-mentioned embodiments are only examples, and the embodiments having the same structure as the technical idea and exerting the same effect within the scope of the technical solution of the present application are all included in the technical scope of the present application. In addition, without departing from the scope of the main purpose of the present application, various modifications that can be thought of by those skilled in the art to the embodiments and other methods of combining some of the constituent elements in the embodiments are also included in the scope of the present 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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