A method for refining and processing bauxite for fracturing proppant

Abstract

This application discloses a method for purifying and processing aluminum ore for fracturing proppant, relating to the field of ore purification technology. The method disclosed in this application includes the following steps: aluminum ore raw materials are sequentially crushed and dry-ground to obtain raw material particles; the raw material particles are placed in a flotation agent, stirred, aerated, and allowed to settle; the scum on the surface of the flotation agent is collected, washed, and a high-quality aluminum ore is obtained; in step S2, the flotation agent is composed of the following raw materials in parts by weight: 3-5 parts sodium carbonate, 5-15 parts polyethylene glycol-polyacrylic acid-N-isopropylacrylamide copolymer, 5-15 parts chitosan-polyurea, 1-2 parts sodium hexadecyl sulfate, 5-10 parts polyacrylamide, and 70-80 parts water. This application provides a method for purifying and processing aluminum ore for fracturing proppant with high purification efficiency and a relatively simple process flow, which can reduce the production cost of fracturing proppant.

Description

Technical Field

[0001] This application relates to the field of ore purification technology, and in particular to a method for purifying and processing aluminum ore for fracturing proppant. Background Technology

[0002] Fracturing proppants possess high fracturing strength and are primarily used for downhole support in oilfields to increase the permeability and productivity of oil and gas reservoirs. Traditional indentation proppants mainly consist of quartz proppants and ceramic proppants. However, quartz proppants have significant limitations in application conditions, and their preparation process has a substantial environmental impact, making them less than ideal indentation proppants. Therefore, the research and development of ceramic proppants is particularly important.

[0003] Ceramsite proppant is produced using high-alumina ore as raw material. However, the production cost of high-alumina ore is relatively high. Therefore, it is necessary to purify and process low-alumina ore from bauxite or mine waste. However, current purification and processing methods for low-alumina ore have drawbacks, including unsatisfactory purification results. Furthermore, most purification and processing methods require advanced technology and equipment, and the processes are relatively complex, increasing both the cost and operational difficulty of purification and processing.

[0004] Therefore, there is an urgent need for a more efficient and simpler aluminum ore purification and processing method to solve the problems existing in the current technology. Summary of the Invention

[0005] In order to solve at least one of the above-mentioned technical problems and to develop a method for purifying and processing aluminum ore with high purification efficiency and a relatively simple process flow, this application provides a method for purifying and processing aluminum ore for fracturing proppant.

[0006] This application provides a method for purifying and processing aluminum ore for fracturing proppant, comprising the following steps:

[0007] S1. The aluminum ore raw material is sequentially crushed and dry-ground to obtain raw material particles;

[0008] S2. Place the obtained raw material particles in a flotation agent, stir, blow air, let stand, take the scum on the top of the flotation agent, wash, and obtain high-quality aluminum ore.

[0009] In step S2, the flotation agent is made from the following raw materials in parts by weight: 3-5 parts sodium carbonate, 5-15 parts polyethylene glycol-polyacrylic acid-N-isopropylacrylamide copolymer, 5-15 parts chitosan-polyurea, 1-2 parts sodium hexadecyl sulfate, 5-10 parts polyacrylamide, and 70-80 parts water.

[0010] By adopting the above technical solution, the purification and processing method provided in this application uses crushing, dry grinding and flotation processes. In the flotation process, this application uses a specific flotation agent to separate aluminum ore from impurities, which can effectively improve the purification efficiency of aluminum ore. At the same time, the purification and processing method provided in this application is simple to operate and can effectively shorten the process flow for purifying and processing aluminum ore. The flotation agent selected in this application, based on sodium carbonate for pH adjustment, sodium hexadecyl sulfate as a foaming agent, and polyacrylamide as a flocculant, employs polyethylene glycol-polyacrylic acid-N-isopropylacrylamide copolymer and chitosan polyurea as collectors. Both polyethylene glycol-polyacrylic acid-N-isopropylacrylamide copolymer and chitosan polyurea have high selectivity and can selectively adsorb onto the surface of aluminum ore, promoting contact and adhesion between aluminum ore and air bubbles during flotation, thereby improving the recovery rate of aluminum ore. At the same time, both substances have good dispersibility and stability, which can effectively inhibit the aggregation of fine impurities after the raw material particles are placed in the flotation agent, improving the stability of the suspension. Moreover, both are environmentally friendly collectors with minimal environmental impact.

[0011] Optionally, in the flotation agent, the sum of the weight parts of the polyethylene glycol-polyacrylic acid-N-isopropylacrylamide copolymer and the chitosan polyurea is 15 to 20 parts.

[0012] By adopting the above technical solution, the selective adsorption of aluminum ore can be improved.

[0013] Optionally, the mass ratio of the polyethylene glycol-polyacrylic acid-N-isopropylacrylamide copolymer and the chitosan polyurea in the flotation agent is 1:1.

[0014] By adopting the above technical solutions, the selective adsorption of aluminum ore can be further improved.

[0015] Optionally, in the polyethylene glycol-polyacrylic acid-N-isopropylacrylamide copolymer, the mass ratio of polyethylene glycol, polyacrylic acid, and N-isopropylacrylamide is 1 to 2:1:1.

[0016] Optionally, the flotation agent is prepared according to the following method:

[0017] Step 1: Provide sodium carbonate, sodium hexadecyl sulfate, polyacrylamide and water according to the weight proportions, mix them to obtain premix one;

[0018] According to the weight parts, polyethylene glycol-polyacrylic acid-N-isopropylacrylamide copolymer and chitosan polyurea are provided and mixed to obtain premix two;

[0019] Step 2: Add the second premix to the first premix and stir to obtain the flotation agent.

[0020] By adopting the above technical solution, the flotation agent prepared by specific steps can stabilize the performance of the flotation agent, thereby further improving the recovery rate of aluminum ore flotation.

[0021] Optionally, in step S1, the crushing process includes sequentially performing primary coarse crushing, secondary medium crushing, and tertiary ore homogenization on the aluminum ore raw material.

[0022] Optionally, in step S1, the dry grinding process includes sequentially performing a first-stage grinding process, a second-stage grinding process, and a fine classification process on the crushed aluminum ore raw material.

[0023] Optionally, the average particle size of the raw material particles is 0.3 to 0.5 mm.

[0024] By adopting the above technical solution, the aluminum ore raw material is crushed and dry-ground to a specific particle size, which can further improve the recovery rate of aluminum ore flotation, thereby improving the purification efficiency of aluminum ore.

[0025] Optionally, in step S2, the blowing operation is as follows: nitrogen gas is introduced into the flotation agent at a gas flow rate of 50-70 L / min.

[0026] In summary, this application includes at least one of the following beneficial technical effects:

[0027] 1. The purification and processing method provided in this application adopts crushing, dry grinding and flotation processes. In the flotation process, this application uses a specific flotation agent to separate aluminum ore from impurities, which can effectively improve the purification efficiency of aluminum ore. At the same time, the purification and processing method provided in this application is simple to operate and can effectively shorten the process flow for purifying and processing aluminum ore.

[0028] 2. The flotation agent selected in this application uses polyethylene glycol-polyacrylic acid-N-isopropylacrylamide copolymer and chitosan polyurea as collectors, which can selectively adsorb onto the surface of aluminum ore, promote the contact and adhesion of aluminum ore with air bubbles during the flotation process, thereby improving the recovery rate of aluminum ore by flotation.

[0029] 3. The flotation agents selected in this application are polyethylene glycol-polyacrylic acid-N-isopropylacrylamide copolymer and chitosan polyurea as collectors. Both have good dispersibility and stability, which can effectively inhibit the aggregation of fine impurities after the raw material particles are placed in the flotation agent, improve the stability of the suspension, and are both environmentally friendly collectors with little impact on the environment. Detailed Implementation

[0030] The present application will be further described in detail below with reference to preparation examples, embodiments and comparative examples.

[0031] This application discloses a method for purifying and processing aluminum ore for fracturing proppant, comprising the following steps:

[0032] S1. The aluminum ore raw material is sequentially crushed and dry-ground to obtain raw material particles;

[0033] S2. Place the obtained raw material particles in a flotation agent, stir, blow air, let stand, take the scum on the top of the flotation agent, wash, and obtain high-quality aluminum ore.

[0034] In step S2, the flotation agent is made from the following raw materials in parts by weight: 3-5 parts sodium carbonate, 5-15 parts polyethylene glycol-polyacrylic acid-N-isopropylacrylamide copolymer, 5-15 parts chitosan-polyurea, 1-2 parts sodium hexadecyl sulfate, 5-10 parts polyacrylamide, and 70-80 parts water.

[0035] Unless otherwise specified, all raw materials used in the preparation examples, embodiments, and comparative examples of this application are commercially available products:

[0036] Aluminum ore raw materials: selected from bauxite and ore waste;

[0037] Sodium carbonate: Shanghai Tandu Industrial Co., Ltd., purity 99.2%;

[0038] Polyethylene glycol-polyacrylic acid-N-isopropylacrylamide copolymer: prepared by mixing polyethylene glycol, polyacrylic acid, and N-isopropylacrylamide in a certain mass ratio; polyethylene glycol: Jinan Jinhao Chemical Co., Ltd., purity 99%; polyacrylic acid: Wuhan Xinweiye Chemical Co., Ltd., purity 98%; N-isopropylacrylamide: Hubei Hengjingrui Chemical Co., Ltd., purity 98%.

[0039] Chitosan-polyurea: Chitosan and urea are mixed in a 1:1 molar ratio, dissolved in acetic acid, heated, filtered, washed, and dried to obtain the product; Chitosan, Hefei Hongrui Biotechnology Co., Ltd., purity 99%; Urea, Langfang Qianyao Technology Co., Ltd., purity 99%.

[0040] Sodium hexadecyl sulfate: Hubei Baidu Chemical Co., Ltd., purity 99%;

[0041] Polyacrylamide: Shandong Yonglida New Material Technology Co., Ltd., purity 99%;

[0042] Water: Selected from tap water.

[0043] The following are preparation examples 1 to 6 and preparation comparative examples 1 to 2 of this application. Preparation examples 1 to 6 and preparation comparative examples 1 to 2 each provide a method for preparing a flotation agent.

[0044] Preparation Example 1

[0045] 3 kg of sodium carbonate, 1 kg of sodium hexadecyl sulfate, 5 kg of polyacrylamide, 70 kg of water, 5 kg of polyethylene glycol-polyacrylic acid-N-isopropylacrylamide copolymer, and 5 kg of chitosan polyurea are mixed to obtain a flotation agent; wherein, in the polyethylene glycol-polyacrylic acid-N-isopropylacrylamide copolymer, the mass ratio between polyethylene glycol, polyacrylic acid, and N-isopropylacrylamide is 1:1:1.

[0046] Preparation Example 2

[0047] Based on Preparation Example 1, the difference between this preparation example and Preparation Example 1 lies in the following: the order of steps in this preparation example is different, including:

[0048] Step 1: Mix 3 kg of sodium carbonate, 1 kg of sodium hexadecyl sulfate, 5 kg of polyacrylamide and 70 kg of water to obtain premix 1;

[0049] 5 kg of polyethylene glycol-polyacrylic acid-N-isopropylacrylamide copolymer and 5 kg of chitosan polyurea were mixed to obtain premix two;

[0050] Step 2: Add premix 2 to premix 1 and stir to obtain flotation agent;

[0051] The remaining steps, conditions, and parameters are the same as in Preparation Example 1.

[0052] Preparation Examples 3-6 and Comparative Examples 1-2 were all based on Preparation Example 2. The difference between them and Preparation Example 2 was that the raw material composition of the flotation agent in Preparation Examples 3-6 and Comparative Examples 1-2 was different, as shown in Table 1; the remaining steps, conditions and parameters were the same as in Preparation Example 2.

[0053] Table 1. Raw material composition of flotation agents in Preparation Examples 2-6 and Comparative Examples 1-2.

[0054]

[0055]

[0056] The following are Examples 1-6 and Comparative Examples 1-2 of this application. Examples 1-6 and Comparative Examples 1-2 respectively provide a method for purifying and processing aluminum ore for fracturing proppant.

[0057] Example 1

[0058] The aluminum ore raw material is subjected to primary coarse crushing, secondary medium crushing, tertiary ore homogenization, primary grinding, secondary grinding, and fine classification in sequence. Particles with an average particle size of 0.3 mm are selected as raw material particles, and the remaining particles are further subjected to dry grinding.

[0059] The obtained raw material particles were placed in the flotation agent prepared in Preparation Example 1, stirred, and nitrogen gas was introduced into the flotation agent at a gas flow rate of 50 L / min. After standing, the scum on the top of the flotation agent was taken, washed, and high-quality aluminum ore was obtained.

[0060] Examples 2-6 and Comparative Examples 1-2 are based on Example 1, except that the flotation agents used are different. Examples 2-6 and Comparative Examples 1-2 use the flotation agents prepared in Preparation Examples 2-6 and Preparation Comparative Examples 1-2, respectively. The remaining steps, conditions and parameters are the same as in Example 1.

[0061] The purity of the aluminum ore provided in Examples 1-6 and Comparative Examples 1-2 was tested using alumina as a reference, and the test results are recorded in Table 2.

[0062] Table 2 Summary of test results for Examples 1-6 and Comparative Examples 1-2

[0063] unit:% Purity of aluminum ore Example 1 85.3 Example 2 87.9 Example 3 88.2 Example 4 88.1 Example 5 88.6 Example 6 88.5 Comparative Example 1 70.1 Comparative Example 2 72.5

[0064] Referring to Table 2, the test results show that the purity of Examples 1-6 is all above 85%, and is significantly higher than that of Comparative Example 1 (70.1%) and Comparative Example 2 (72.5%). This demonstrates the superiority of using polyethylene glycol-polyacrylic acid-N-isopropylacrylamide copolymer and chitosan polyurea as collectors in the flotation agents used in this application. Furthermore, the test results of Examples 1-6 show that the purity of Examples 2-6 is higher than that of Example 1, demonstrating the superiority of the flotation agents prepared using a specific sequence of steps. Additionally, Examples 2-4 and Examples 5-6 reveal that polyethylene glycol-polyacrylic acid-N-isopropylacrylamide copolymer and chitosan polyurea have a significant impact on the purity of aluminum ore in the refined aluminum ore.

[0065] Preparation Examples 7-9

[0066] Based on Preparation Example 3, the difference between Preparation Examples 7-9 and Preparation Example 3 is that the raw material composition of the flotation agent in Preparation Examples 7-9 is different, see Table 3; the remaining steps, conditions and parameters are the same as in Preparation Example 3.

[0067] Table 3 shows the raw material composition of the flotation agents in Preparation Examples 3 and 7-9.

[0068]

[0069] Examples 7-9

[0070] Examples 7-9 are based on Example 3, except that the flotation agents used are different. Examples 7-9 use the flotation agents prepared in Examples 7-9 respectively. The remaining steps, conditions and parameters are the same as in Example 3.

[0071] The purity of the aluminum ore provided in Examples 7-9 was tested using alumina as a reference, and the test results are recorded in Table 4.

[0072] Table 4 Summary of test results for Examples 7-9

[0073] unit:% Purity of aluminum ore Example 7 89.1 Example 8 89.7 Example 9 89.4

[0074] Referring to Table 4, the test results in Table 4 show that the purity of Examples 7 to 9 is all above 89%, which demonstrates the superiority of the sum of the weight parts of polyethylene glycol-polyacrylic acid-N-isopropylacrylamide copolymer and chitosan polyurea within a specific range.

[0075] Preparation Examples 10-11

[0076] Based on Preparation Example 8, the difference between Preparation Examples 10 and 11 and Preparation Example 8 is that the raw material composition of the flotation agent in Preparation Examples 10 and 11 is different, see Table 5; the remaining steps, conditions and parameters are the same as in Preparation Example 8.

[0077] Table 5. Raw material composition of the flotation agents in Preparation Examples 8 and 10-11

[0078]

[0079] Examples 10-11

[0080] Examples 10-11 are based on Example 8, except that the flotation agents used are different. Examples 10-11 use the flotation agents prepared in Preparation Examples 10-11 respectively; the remaining steps, conditions and parameters are the same as in Example 8.

[0081] The purity of the aluminum ore provided in Examples 10-11 was tested using alumina as a reference, and the test results are recorded in Table 6.

[0082] Table 6 Summary of test results for Examples 10-11

[0083] unit:% Purity of aluminum ore Example 10 89.9 Example 11 90.7

[0084] Referring to Table 6, the test results in Table 6 show that the purity of Examples 10-11 is all above 89%, and the purity of Example 11 is higher than that of Examples 8 and 10. This demonstrates the superiority of selecting a specific mass ratio of polyethylene glycol-polyacrylic acid-N-isopropylacrylamide copolymer and chitosan polyurea within a specific sum of weight parts.

[0085] Preparation Examples 12-15

[0086] Based on Preparation Example 11, the difference between Preparation Examples 12 to 15 and Preparation Example 11 is that the mass ratio of polyethylene glycol, polyacrylic acid, and N-isopropylacrylamide in the polyethylene glycol-polyacrylic acid-N-isopropylacrylamide copolymer used in Preparation Examples 12 to 15 is different, being 1.5:1:1, 2:1:1, 1:2:2, and 3:1:1, respectively; the remaining steps, conditions, and parameters are the same as in Preparation Example 11.

[0087] Examples 12-15

[0088] Examples 12-15 are based on Example 11, except that the flotation agents used are different. Examples 12-15 use the flotation agents prepared in Examples 12-15 respectively. The remaining steps, conditions and parameters are the same as in Example 11.

[0089] The purity of the aluminum ore provided in Examples 12-15 was tested using alumina as a reference, and the test results are recorded in Table 7.

[0090] Table 7 Summary of test results for Examples 12-15

[0091] unit:% Purity of aluminum ore Example 12 91.3 Example 13 90.9 Example 14 89.7 Example 15 89.9

[0092] Referring to Table 7, the test results in Table 7 show that the purity of Examples 12 to 15 is all above 89%, and the purity of Examples 11 to 13 is all above 90%, which is higher than that of Examples 14 to 15. This demonstrates the superiority of the polyethylene glycol-polyacrylic acid-N-isopropylacrylamide copolymer prepared at a specific mass ratio.

[0093] Examples 16-19

[0094] Examples 16 to 19 are all based on Example 12, except that the average particle size of the raw material particles screened is different, namely 0.4 mm, 0.5 mm, 0.1 mm and 0.8 mm respectively; the remaining steps, conditions and parameters are the same as in Example 12.

[0095] The purity of the aluminum ore provided in Examples 16-19 was tested using alumina as a reference, and the test results are recorded in Table 8.

[0096] Table 8 Summary of test results for Examples 16-19

[0097] unit:% Purity of aluminum ore Example 16 91.7 Example 17 91.4 Example 18 91.8 Example 19 90.2

[0098] Referring to Table 8, the test results in Table 8 show that the purity of Examples 16 to 19 is all above 90%, and the purity of Examples 12 and Examples 16 to 17 is all above 91%, which is higher than that of Examples 18 to 19. This demonstrates the superiority of raw material particles with a specific average particle size.

[0099] Examples 20-21

[0100] Examples 20 and 21 are based on Example 16, except that the gas flow rates used are different, being 60 L / min and 70 L / min respectively; the remaining steps, conditions and parameters are the same as in Example 16.

[0101] In the aluminum ore fines provided in Examples 20-21, the purity of the aluminum ore was tested based on alumina, and the test results were recorded in Table 9.

[0102] Table 9 Summary of test results for Examples 20-21

[0103] unit:% Purity of aluminum ore Example 20 92.1 Example 21 91.9

[0104] Referring to Table 9, the test results in Table 9 show that the purity of Examples 20-21 is all above 91%, which illustrates the superiority of selecting a specific range of gas flow rates.

[0105] In summary, the bauxite purification and processing method for fracturing proppant provided in this application has advantages.

[0106] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A method for purifying and processing bauxite for fracturing proppant, characterized in that, Includes the following steps: S1. The aluminum ore raw material is sequentially crushed and dry-ground to obtain raw material particles; S2. Place the obtained raw material particles in a flotation agent, stir, blow air, let stand, take the scum on the top of the flotation agent, wash, and obtain high-quality aluminum ore. In step S2, the flotation agent is made from the following raw materials in parts by weight: 3-5 parts sodium carbonate, 5-15 parts polyethylene glycol-polyacrylic acid-N-isopropylacrylamide copolymer, 5-15 parts chitosan-polyurea, 1-2 parts sodium hexadecyl sulfate, 5-10 parts polyacrylamide, and 70-80 parts water.

2. The method for purifying and processing bauxite for fracturing proppant according to claim 1, characterized in that, In the flotation agent, the sum of the weight parts of the polyethylene glycol-polyacrylic acid-N-isopropylacrylamide copolymer and the chitosan polyurea is 15 to 20 parts.

3. The method for purifying and processing bauxite for fracturing proppant according to claim 2, characterized in that, In the flotation agent, the mass ratio between the polyethylene glycol-polyacrylic acid-N-isopropylacrylamide copolymer and the chitosan polyurea is 1:

1.

4. The method for purifying and processing bauxite for fracturing proppant according to claim 1, characterized in that, In the polyethylene glycol-polyacrylic acid-N-isopropylacrylamide copolymer, the mass ratio of polyethylene glycol, polyacrylic acid, and N-isopropylacrylamide is 1~2:1:

1.

5. The method for purifying and processing bauxite for fracturing proppant according to any one of claims 1-4, characterized in that, The flotation agent is prepared according to the following method: Step 1: Provide sodium carbonate, sodium hexadecyl sulfate, polyacrylamide and water according to the weight proportions, mix them to obtain premix one; Polyethylene glycol-polyacrylic acid-N-isopropylacrylamide copolymer and chitosan polyurea are provided in parts by weight and mixed to obtain premix two; Step 2: Add the second premix to the first premix and stir to obtain the flotation agent.

6. The method for purifying and processing bauxite for fracturing proppant according to claim 1, characterized in that, In step S1, the crushing process includes sequentially performing primary coarse crushing, secondary medium crushing, and tertiary ore homogenization on the aluminum ore raw material.

7. The method for purifying and processing bauxite for fracturing proppant according to claim 1, characterized in that, In step S1, the dry grinding process includes sequentially performing a first-stage grinding process, a second-stage grinding process, and a fine classification process on the crushed aluminum ore raw material.

8. The method for purifying and processing bauxite for fracturing proppant according to claim 1, characterized in that, The average particle size of the raw material particles is 0.3~0.5mm.

9. The method for purifying and processing bauxite for fracturing proppant according to claim 1, characterized in that, In step S2, the blowing operation is as follows: nitrogen gas is introduced into the flotation agent at a gas flow rate of 50~70L / min.

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