Model selection method of polyacrylamide flocculant for tailing concentration

Abstract

The invention provides a type selection method of a polyacrylamide flocculant for tailing concentration. The polyacrylamide type selection method comprises the following steps: preparing polyacrylamide of each alternative type into polyacrylamide with the same concentration as a test sample; the method comprises the following steps: preparing tailings into turbid liquid with specific concentration, adding each alternative polyacrylamide test sample into the turbid liquid, and blowing nitrogen into the turbid liquid at the same time; and taking solids floating above the turbid liquid within a preset time period, and drying the solids. And calculating the mass percent of the solid minerals in the tailings. And then selecting proper polyacrylamide according to the mass percent of the solid mineral corresponding to the polyacrylamide of each alternative model. By means of the type selection method, the appropriate polyacrylamide flocculant can be accurately and rapidly selected for the tailings, and then the concentration efficiency of the tailings is improved.

Description

Technical Field

[0001] The invention relates to the technical field of tailings treatment, in particular to a method for selecting a polyacrylamide flocculant for tailings concentration. Background Art

[0002] In the process of mining production, a large amount of tailings will be generated. The treatment of tailings has always been one of the important issues in the mining field. Tailings concentration is an important part of tailings treatment. Through concentration, the volume of tailings can be reduced and the cost of tailings treatment can be reduced. Polyacrylamide flocculant is a commonly used tailings thickener, which can quickly agglomerate the solid particles in the tailings into larger particles, thereby accelerating the sedimentation rate of the tailings and improving the concentration efficiency of the tailings.

[0003] However, different types of polyacrylamide flocculants have great differences in performance, and how to choose the right polyacrylamide flocculant is crucial for tailings thickening. At present, the commonly used polyacrylamide flocculant selection method is mainly through experience judgment or small-scale tests. This method has certain blindness and uncertainty, and it is difficult to select the most suitable flocculant. Summary of the invention

[0004] Based on the above problems, the present invention provides a method for selecting a polyacrylamide flocculant for tailings concentration. The selection method can accurately and quickly select a suitable polyacrylamide flocculant for tailings, thereby improving the concentration efficiency of tailings.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] A method for selecting a polyacrylamide flocculant for tailings concentration comprises the following steps:

[0007] Step 1: preparing multiple candidate polyacrylamide flocculant samples into test solutions with equal concentrations; preparing tailings into multiple tailings suspensions with preset concentrations, wherein the multiple test solutions correspond to the multiple tailings suspensions one by one;

[0008] Step 2: Mixing the plurality of test solutions with the plurality of tailings suspensions one by one to obtain a plurality of mixed solutions;

[0009] Step 3: nitrogen is injected into the plurality of mixed liquids respectively for the same period of time, and then the mixed liquid within a preset distance below the liquid surface of each mixed liquid is collected as a calculation sample;

[0010] Step 4: performing solid-liquid separation on each of the calculated samples to obtain a separated solid phase product;

[0011] Step 5: Calculate the mass percentage of each solid phase product in the tailings in the corresponding mixed solution, and take the candidate polyacrylamide flocculant sample corresponding to the solid phase product with the largest mass percentage as the target polyacrylamide flocculant.

[0012] In some of the embodiments, the mass concentration of the candidate polyacrylamide flocculant in the test solution is 0.1%-0.5%.

[0013] In some of the embodiments, the mass concentration of tailings in the tailings suspension is 15%-40%.

[0014] In some of the embodiments, the tailings have a particle size of 20 μm-75 μm.

[0015] In some of the embodiments, during the process of mixing the plurality of test solutions with the plurality of tailings suspensions in a one-to-one correspondence, nitrogen is bubbled into the tailings suspensions.

[0016] In some embodiments, the nitrogen blowing rate is 0.5 L / min-2 L / min.

[0017] In some embodiments, nitrogen is introduced into the mixed solution for a period of 5 min to 20 min.

[0018] In some embodiments, the preset distance is 0.2 to 0.7 times the depth of the mixed liquid.

[0019] In some embodiments, collecting the mixed liquid within a preset distance below the liquid surface of each mixed liquid as the calculation sample includes: sucking the mixed liquid within the preset distance from the liquid surface of the mixed liquid as the calculation sample.

[0020] In some embodiments, the solid-liquid separation process includes one or more of a centrifugal process and a filtration process.

[0021] Beneficial Effects

[0022] Different from the currently commonly used method of selecting by sedimentation, the present invention creatively proposes a method for selecting polyacrylamide flocculants for tailings concentration. The selection method first mixes multiple polyacrylamide flocculants of equal concentration with multiple tailings suspensions one by one. Then, nitrogen is bubbled into the mixed liquid. After a certain period of time, the mixed liquid within a preset distance from the liquid surface of each mixed liquid is collected as a calculation sample. The calculated sample is then subjected to solid-liquid separation to obtain a solid phase product. The applicability of each candidate polyacrylamide flocculant sample is evaluated by calculating the mass percentage of the solid phase product in the corresponding mixed liquid to the tailings, and the candidate polyacrylamide flocculant sample corresponding to the solid phase product with the largest mass percentage is used as the target polyacrylamide flocculant. The selection method can accurately and quickly screen out polyacrylamide flocculants that are compatible with tailings, and provides a new method for the selection of polyacrylamide flocculants for tailings concentration.

[0023] Furthermore, in the selection method of the present invention, the blowing of nitrogen can reduce the contact between tailings and oxygen in the mixed liquid, thereby reducing the adverse effects of oxidation of tailings on the selection results, thereby making the selection method more accurate. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 The present invention is a flowchart of a method for selecting a polyacrylamide flocculant for tailings thickening according to one embodiment of the present invention. DETAILED DESCRIPTION

[0025] When treating tailings, different types of polyacrylamide flocculants have great differences in performance. How to choose the right polyacrylamide flocculant is crucial for tailings concentration treatment. At present, the commonly used polyacrylamide flocculant selection method is mainly through experience judgment or small-scale tests. This method has certain blindness and uncertainty, and it is difficult to select the most suitable flocculant.

[0026] See also Figure 1, one embodiment of the present invention provides a method for selecting a polyacrylamide flocculant for tailings concentration. The selection method comprises the following steps: Step 1: multiple candidate polyacrylamide flocculant samples are configured into test solutions of equal concentration; the tailings are configured into multiple tailings suspensions with preset concentrations, and the multiple test solutions correspond to the multiple tailings suspensions one by one. Step 2: multiple test solutions are mixed with multiple tailings suspensions one by one to obtain multiple mixed solutions. Step 3: nitrogen is respectively injected into the multiple mixed solutions, and after the nitrogen is injected for the same time, the mixed solutions within a preset distance from the liquid surface of each mixed solution are collected as calculation samples. Step 4: solid-liquid separation treatment is performed on each of the calculated samples to obtain separated solid phase products. Step 5: Calculate the mass percentage of each solid phase product in the corresponding mixed solution, and the candidate polyacrylamide flocculant sample corresponding to the solid phase product with the largest mass percentage is used as the target polyacrylamide flocculant.

[0027] Different from the currently commonly used method of selecting by sedimentation, the present invention creatively proposes a method for selecting polyacrylamide flocculants for tailings concentration. The selection method first mixes multiple polyacrylamide flocculants of equal concentration with multiple tailings suspensions one by one. Then, nitrogen is bubbled into the mixed liquid. After a certain period of time, the mixed liquid within a preset distance from the liquid surface of each mixed liquid is collected as a calculation sample. The calculated sample is then subjected to solid-liquid separation to obtain a solid phase product. The applicability of each candidate polyacrylamide flocculant sample is evaluated by calculating the mass percentage of the solid phase product in the corresponding mixed liquid to the tailings, and the candidate polyacrylamide flocculant sample corresponding to the solid phase product with the largest mass percentage is used as the target polyacrylamide flocculant. The selection method can accurately and quickly screen out polyacrylamide flocculants that are compatible with tailings, and provides a new method for the selection of polyacrylamide flocculants for tailings concentration.

[0028] Furthermore, in the selection method of the present invention, the blowing of nitrogen can reduce the contact between tailings and oxygen in the mixed liquid, thereby reducing the adverse effects of oxidation of tailings on the selection results, thereby making the selection method more accurate.

[0029] Optionally, the number of the plurality of candidate polyacrylamide flocculant samples may be 2 to 10. For example, the number of the plurality of candidate polyacrylamide flocculant samples may be 2, 3, 4, 5, 6, 7, 8, 9, 10, etc.

[0030] Optionally, in order to further improve the efficiency of polyacrylamide flocculant selection, the mass concentration of tailings in multiple tailings suspensions is equal. For example, a tailings suspension with a preset concentration can be prepared first, and then the tailings suspension can be evenly divided into multiple portions.

[0031] In some of the embodiments, the mass concentration of the alternative polyacrylamide flocculant in the test solution is 0.1%-0.5%. If the mass concentration of the alternative polyacrylamide flocculant in the test solution is too low, it is difficult to achieve a good flocculation effect. If the mass concentration of the alternative polyacrylamide flocculant in the test solution is too high, it may combine too much with impurities in the tailings, affecting the accuracy of the selection result. Optionally, the mass concentration of the alternative polyacrylamide flocculant in the test solution can be 0.1%, 0.2%, 0.3%, 0.4%, 0.5%. It is understandable that the mass concentration of the alternative polyacrylamide flocculant in the test solution can also be other suitable selections within the range of 0.1%-0.5%. Optionally, the solvent in the test solution is water.

[0032] In some embodiments, the mass concentration of tailings in the tailings suspension is 15%-40%. That is, the preset concentration is 15%-40%. If the mass concentration of tailings in the tailings suspension is too small, it will prolong the time of polyacrylamide selection and tailings treatment, and reduce the efficiency of polyacrylamide selection and tailings treatment. If the mass concentration of tailings in the tailings suspension is too large, it is difficult to accurately reflect the actual working conditions of the tailings. At the same time, if the mass concentration of tailings in the tailings suspension is too large, a large amount of polyacrylamide flocculant will be consumed, which will increase the cost of polyacrylamide selection and tailings treatment. Optionally, the mass concentration of tailings in the tailings suspension can be but is not limited to 15%, 16%, 17%, 18%, 19%, 20%, 22%, 25%, 28%, 30%, 32%, 35%, 38%, 40%, etc. It is understandable that the mass concentration of tailings in the tailings suspension can also be other suitable choices within the range of 15%-40%.

[0033] In some of the embodiments, the particle size of the tailings is 20μm-75μm. If the particle size of the tailings is too small or too small to accurately reflect the actual working conditions of the tailings, it may cause the selected polyacrylamide flocculant to be poorly compatible with the tailings. In addition, if the particle size of the tailings is too large, it may lead to an increase in the consumption of polyacrylamide and increase the selection cost of the polyacrylamide flocculant. Optionally, the particle size of the tailings can be 20μm, 25μm, 30μm, 35μm, 40μm, 45μm, 50μm, 55μm, 60μm, 65μm, 70μm, etc. It is understandable that the particle size of the tailings can also be other suitable choices within the range of 20μm-75μm.

[0034] In some of the embodiments, in the process of mixing the multiple test solutions with the multiple tailings suspensions in a one-to-one correspondence, nitrogen is bubbled into the tailings suspension. The bubbling of nitrogen can improve the interaction between the test solution and the tailings suspension, and promote the mixing of the test solution and the tailings suspension. Optionally, in the process of mixing the multiple test solutions with the multiple tailings suspensions in a one-to-one correspondence, nitrogen is bubbled into the tailings suspension, and the bubbling speed of nitrogen is 0.5L / min-2L / min. Optionally, the bubbling speed of nitrogen can be but is not limited to 0.5L / min, 0.8L / min, 1L / min, 1.2L / min, 1.5L / min, 1.8L / min, 2L / min, etc. It is understandable that the bubbling speed of nitrogen can also make other suitable choices within the range of 0.5L / min-2L / min.

[0035] In some embodiments, when nitrogen is added to the mixed solution, the bubbling speed of nitrogen is 0.5L / min-2L / min. Optionally, the bubbling speed of nitrogen can be but not limited to 0.5L / min, 0.8L / min, 1L / min, 1.2L / min, 1.5L / min, 1.8L / min, 2L / min, etc. It is understandable that the bubbling speed of nitrogen can also make other suitable choices within the range of 0.5L / min-2L / min. It is also understandable that in the process of mixing multiple test solutions with multiple tailings suspensions one by one, nitrogen is bubbling into the tailings suspension, the bubbling of nitrogen is maintained, and then nitrogen is bubbling into the mixed solution. That is, nitrogen is continuously bubbling, and in the process of mixing multiple test solutions with multiple tailings suspensions one by one, the bubbling speed of nitrogen is equal when bubbling nitrogen into the tailings suspension and bubbling nitrogen into the tailings suspension.

[0036] In some embodiments, nitrogen is added to the mixed solution, and the time of nitrogen bubbling is 5min-20min. If the nitrogen bubbling time is too short, it is difficult to fully exert the effect of nitrogen. If the nitrogen bubbling time is too long, the time of polyacrylamide flocculant selection will be prolonged, and the selection efficiency will be reduced. Optionally, nitrogen is added to the mixed solution, and the time of nitrogen bubbling can be but not limited to 5min, 6min, 7min, 8min, 9min, 10min, 11min, 12min, 13min, 14min, 15min, 16min, 17min, 18min, 19min, 20min, etc. It is understandable that the time of nitrogen bubbling can also be other suitable selections within the range of 5min-20min.

[0037] In some embodiments, the preset distance is 0.2 to 0.7 times the depth of the mixed solution. When the preset distance is too small, the mass of the collected tailings is too small, and the obtained results are difficult to fully reflect the flocculation effect of the polyacrylamide flocculant. When the preset distance is too large, the mass of the collected tailings is too large, and it is difficult to fully reflect the actual flocculation effect of the polyacrylamide flocculant.

[0038] It is understood that the depth of the mixed liquid represents the distance from the liquid surface of the mixed liquid to the bottom of the mixed liquid. Optionally, the preset distance is 0.2 times, 0.3 times, 0.4 times, 0.5 times, 0.6 times, 0.7 times, etc., of the depth of the mixed liquid. It is also understood that the preset distance can also be other values ​​within the range of 0.2 times to 0.7 times of the depth of the mixed liquid.

[0039] In some embodiments, collecting the mixed liquid within a preset distance below the liquid surface of each mixed liquid as the calculation sample includes: sucking the mixed liquid within the preset distance from the liquid surface of the mixed liquid as the calculation sample. By sucking, the mixed liquid within the preset distance can be fully collected, and the influence of the mixed liquid below the preset distance on the selection result can be avoided, thereby further improving the accuracy of the polyacrylamide flocculant selection.

[0040] In some embodiments, the solid-liquid separation treatment includes one or more of a centrifugal treatment and a filtration treatment. It is understood that after the solid-liquid separation treatment, the water in the solid phase product can be further removed by drying, thereby improving the accuracy of the quality of the collected tailings and further improving the accuracy of the selection of the polyacrylamide flocculant.

[0041] Another embodiment of the present invention provides a method for selecting a polyacrylamide flocculant for tailings concentration. The selection method comprises the following steps:

[0042] S01: multiple candidate polyacrylamide flocculant samples are configured into test solutions with equal concentrations; tailings are configured into multiple tailings suspensions with preset concentrations, and the multiple test solutions correspond to the multiple tailings suspensions one by one. The mass concentration of the candidate polyacrylamide flocculant in the test solution is 0.1%-0.5%. The particle size of the tailings is 20μm-75μm. The mass concentration of tailings in the tailings suspension is 15%-40%.

[0043] S02: Multiple test solutions are mixed with multiple tailings suspensions one by one to obtain multiple mixed solutions. During the mixing process, nitrogen is blown into the tailings suspension. The blowing rate of nitrogen is 0.5L / min-2L / min.

[0044] S03: Nitrogen is injected into the multiple mixed liquids respectively, and after the same time, the mixed liquid within a preset distance below the liquid surface of each mixed liquid is collected as a calculation sample. The nitrogen injection speed is 0.5L / min-2L / min. The time for blowing nitrogen is 5min-20min. The preset distance is 0.2 times-0.7 times the depth of the mixed liquid. Optionally, collecting the mixed liquid within a preset distance below the liquid surface of each mixed liquid as the calculation sample includes: sucking the mixed liquid within the preset distance from the liquid surface of the mixed liquid as the calculation sample.

[0045] S04: Perform solid-liquid separation on each of the calculated samples to obtain a separated solid phase product. The solid-liquid separation process includes one or more of a centrifugal process and a filtration process.

[0046] S05: Calculate the mass percentage of each solid phase product in the tailings in the corresponding mixed solution, and take the candidate polyacrylamide flocculant sample corresponding to the solid phase product with the largest mass percentage as the target polyacrylamide flocculant.

[0047] The technical solution of the present invention is described in detail below in conjunction with specific embodiments.

[0048] Example 1

[0049] The selection method of the polyacrylamide flocculant used for tailings concentration in this embodiment is:

[0050] S101: 4 candidate polyacrylamide flocculant samples (respectively referred to as sample A, sample B, sample C, and sample D) are prepared into test solutions with a mass concentration of 0.5%. Tailings with a particle size of 70 μm are prepared into 4 suspensions with a mass concentration of 15%.

[0051] S102: Four test solutions are mixed with four tailings suspensions one by one to obtain multiple mixed solutions. During the mixing process, nitrogen is bubbled into the tailings suspensions at a rate of 1 L / min.

[0052] S103: Nitrogen is injected into each of the four mixed solutions at a rate of 1 L / min. After bubbling nitrogen for 10 minutes, the mixed solution within a preset distance is drawn from the surface of the mixed solution as a calculation sample. The preset distance is 0.4 times the depth of the mixed solution.

[0053] S104: Centrifuge and dry each calculated sample to obtain a separated solid phase product.

[0054] S05: Calculate the mass percentage of each solid phase product in the tailings in the corresponding mixed solution, and the mass percentages are 2.2% (sample A), 2.8% (sample B), 2.5% (sample C), and 2.1% (sample D). It can be seen that the mass percentage corresponding to sample B is the largest, so sample B is used as the target polyacrylamide flocculant.

[0055] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

[0056] For those skilled in the art, according to the concept of the present invention, there may be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A method for selecting a polyacrylamide flocculant for tailings concentration, characterized in that: The steps include: Step 1: preparing multiple candidate polyacrylamide flocculant samples into test solutions with equal concentrations; preparing tailings into multiple tailings suspensions with preset concentrations, wherein the multiple test solutions correspond to the multiple tailings suspensions one by one; Step 2: Mixing the plurality of test solutions with the plurality of tailings suspensions one by one to obtain a plurality of mixed solutions; Step 3: nitrogen is injected into the plurality of mixed liquids respectively for the same period of time, and then the mixed liquid within a preset distance below the liquid surface of each mixed liquid is collected as a calculation sample; Step 4: performing solid-liquid separation on each of the calculated samples to obtain a separated solid phase product; Step 5: Calculate the mass percentage of each solid phase product in the tailings in the corresponding mixed solution, and take the candidate polyacrylamide flocculant sample corresponding to the solid phase product with the largest mass percentage as the target polyacrylamide flocculant.

2. The method for selecting a polyacrylamide flocculant for tailings concentration according to claim 1, characterized in that: The mass concentration of the candidate polyacrylamide flocculant in the test solution is 0.1%-0.5%.

3. The method for selecting a polyacrylamide flocculant for tailings concentration according to claim 1, characterized in that: The mass concentration of tailings in the tailings suspension is 15%-40%.

4. The method for selecting a polyacrylamide flocculant for tailings concentration according to claim 1, characterized in that: The particle size of the tailings is 20 μm-75 μm.

5. The method for selecting a polyacrylamide flocculant for tailings concentration according to claim 1, characterized in that: During the process of mixing the plurality of test solutions with the plurality of tailings suspensions in a one-to-one correspondence, nitrogen gas is bubbled into the tailings suspensions.

6. The method for selecting a polyacrylamide flocculant for tailings concentration according to claim 1, characterized in that: The nitrogen blowing rate is 0.5L / min-2L / min.

7. The method for selecting a polyacrylamide flocculant for tailings concentration according to claim 1, characterized in that: Nitrogen is introduced into the mixed solution for 5 min to 20 min.

8. The method for selecting a polyacrylamide flocculant for tailings concentration according to claim 1, characterized in that: The preset distance is 0.2 to 0.7 times the depth of the mixed liquid.

9. The method for selecting a polyacrylamide flocculant for tailings concentration according to any one of claims 1 to 8, characterized in that: Collecting the mixed liquid within a preset distance downward from the liquid surface of each mixed liquid as the calculation sample includes: sucking the mixed liquid within the preset distance from the liquid surface of the mixed liquid as the calculation sample.

10. The method for selecting a polyacrylamide flocculant for tailings concentration according to any one of claims 1 to 9, characterized in that: The solid-liquid separation process includes one or more of a centrifugal process and a filtration process.

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