Combined grinding aid as well as preparation method and application thereof

Abstract

The invention provides a combined grinding aid as well as a preparation method and application thereof, and belongs to the technical field of ore grinding. The combined grinding aid is prepared from the following raw materials in parts by weight: 20 to 30 parts of sodium hexametaphosphate, 6 to 8 parts of 2-methylvaleric acid, 3 to 5 parts of cinnamyl propionate and 3 to 5 parts of alkalized molasses. According to the obtained combined grinding aid, the grinding efficiency of quartz can be greatly improved, the content of particles with the particle size being-0.043 mm can reach 85% or above, the usage amount of the grinding aid is very low, and good economical efficiency is achieved; meanwhile, after the combined grinding aid is used for ore grinding, the recovery rate of subsequent flotation of quartz can be increased.

Description

Technical Field

[0001] The present invention relates to the technical field of mineral grinding, and particularly relates to a combined grinding aid, a preparation method thereof, and an application thereof. Background Art

[0002] Adding a small amount of chemical additives (gaseous, liquid or solid chemical substances) during the grinding process can significantly improve the grinding efficiency or reduce the energy consumption and steel consumption during the grinding process. Such chemical additives are usually referred to as grinding aids.

[0003] The main component of quartz is SiO2, which is colorless and transparent and often contains a small amount of impurity components. Whether it is discarded as a gangue mineral or purified as a non-metallic mineral raw material, flotation is one of the effective methods, and at the same time, grinding it is also a necessary process. Therefore, studying an efficient grinding method that is beneficial to flotation is an important research direction for quartz.

[0004] At present, the grinding aids for quartz are mainly single-component grinding aids. As recorded in "The Influence of Grinding Aids on the Grinding Effect and Flotation Behavior of Quartz", the commonly used quartz grinding aids include sodium hexametaphosphate, sodium silicate, as well as acetone, ammonium chloride, sodium chloride, etc. Sodium hexametaphosphate is a commonly used grinding aid for minerals and is also commonly used in the grinding of quartz. Although it has a certain grinding effect, its effect is limited and the improvement in economy is insufficient.

[0005] In addition to single-component grinding aids, some combined grinding aids have also been studied in this field. For example, a combined grinding aid is obtained by combining sodium hexametaphosphate and sodium silicate, or by combining different alkanolamines, alcohols, or some inorganic salts (such as calcium chloride, calcium formate, etc.). However, there are still problems such as a relatively high addition amount required during grinding and a not significant increase in the grinding efficiency. For example, in the paper "Study on the Influence of Combined Grinding Aids on the Grinding of Quartz and Its Action Mechanism" by Mao Yong et al., the authors combined sodium hexametaphosphate and sodium silicate and investigated the effect of this combination on the grinding of quartz. The results showed that when using a grinding aid composed of sodium hexametaphosphate and sodium silicate, the content of particles with a particle size of -0.043 mm was 9.9 percentage points higher than that without using a grinding aid. In addition, Chinese Patent No. 202210557213.9 discloses another combined grinding aid, which is composed of CaCl2, triisopropanolamine, and triethanolamine. The content of particles with a particle size of -0.043 mm can be increased by 15 percentage points compared with that without adding a grinding aid, and is also 9 percentage points higher than the scheme using sodium hexametaphosphate as a grinding aid. In addition, "The Influence of Grinding Aids Glycerol and Sodium Pyrophosphate on the Grinding Kinetics Parameters of Quartz" also discloses adding glycerol and sodium pyrophosphate to the grinding aid.

[0006] Generally speaking, an increase in grinding efficiency does not necessarily mean an increase in the recovery rate of quartz flotation. For example, although acetone and ammonium chloride mentioned in the aforementioned paper "Influence of grinding aids on the grinding effect and flotation behavior of quartz" improve the grinding efficiency, they have an adverse effect on the subsequent flotation recovery rate.

[0007] Based on this, it is very important to provide a combined grinding aid for simultaneously improving the grinding efficiency and flotation recovery rate of quartz. Summary of the Invention

[0008] The purpose of the present invention is to provide a combined grinding aid and its preparation method and application to solve the technical problem in the prior art that it is impossible to simultaneously meet the content of -0.043mm particle size during quartz grinding and the subsequent flotation recovery rate.

[0009] To achieve the above-mentioned invention purpose, the present invention provides the following technical solutions:

[0010] The present invention provides a combined grinding aid, comprising the following raw materials in parts by weight:

[0011] Sodium hexametaphosphate 20 - 30 parts,

[0012] 2-Methylvaleric acid 6 - 8 parts,

[0013] Cinnamyl propionate 3 - 5 parts,

[0014] Alkalized molasses 3 - 5 parts.

[0015] Further, it comprises the following raw materials in parts by weight: sodium hexametaphosphate 25 parts, 2-methylvaleric acid 7 parts, cinnamyl propionate 4 parts, and alkalized molasses 4 parts.

[0016] Further, the molasses used for the alkalized molasses includes beet molasses.

[0017] Further, the preparation method of the alkalized molasses is as follows:

[0018] Mix molasses and water to obtain a molasses solution, adjust the pH to 11 - 13, then carry out a reaction, and after the reaction is completed, dry it to obtain the product.

[0019] Further, the mass fraction of the molasses solution is 40 - 60%;

[0020] The reagent used for adjusting the pH is sodium hydroxide.

[0021] Further, the temperature of the reaction is 70 - 80°C, and the reaction time is 1 - 3h.

[0022] Further, the drying temperature is 50 - 70°C.

[0023] The present invention provides a preparation method of a combined grinding aid. The method comprises mixing sodium hexametaphosphate, 2-methylvaleric acid, cinnamyl propionate and alkalized molasses.

[0024] The present invention also provides an application of the combined grinding aid in the pretreatment of quartz before flotation of quartz.

[0025] Advantages of the present invention:

[0026] The combined grinding aid prepared by the present invention can greatly improve the grinding efficiency of quartz. The content of -0.043mm particle size fraction can reach more than 85%, and the dosage of the grinding aid is very low, having good economy. At the same time, after grinding with the combined grinding aid of the present invention, the recovery rate of subsequent flotation of quartz can be improved. Specific embodiments

[0027] The present invention provides a combined grinding aid, which comprises the following raw materials in parts by weight:

[0028] 20-30 parts of sodium hexametaphosphate,

[0029] 6-8 parts of 2-methylvaleric acid,

[0030] 3-5 parts of cinnamyl propionate,

[0031] 3-5 parts of alkalized molasses.

[0032] Preferably, the combined grinding aid comprises the following raw materials in parts by weight: 22-28 parts of sodium hexametaphosphate, 6.5-7.5 parts of 2-methylvaleric acid, 3.5-4.5 parts of cinnamyl propionate, and 3.5-4.5 parts of alkalized molasses.

[0033] More preferably, the combined grinding aid comprises the following raw materials in parts by weight: 25 parts of sodium hexametaphosphate, 7 parts of 2-methylvaleric acid, 4 parts of cinnamyl propionate, and 4 parts of alkalized molasses.

[0034] In the present invention, the molasses used for the alkalized molasses is preferably beet molasses.

[0035] In the present invention, molasses is commonly used as a grinding aid for cement. Only by combining alkalized molasses with the other three components of the present invention can the grinding effect be effectively improved. Generally speaking, under alkaline conditions, molasses will generate saccharinic acid and its salts, aldonic acid salts and amino carbonic acid and its salts, and these components all have certain surface activity.

[0036] In the present invention, the preparation method of the alkalized molasses is as follows:

[0037] Mix molasses and water to obtain a molasses solution, adjust the pH to 11-13, then carry out a reaction, and after the reaction is completed, dry it to obtain the product.

[0038] In the present invention, the mass fraction of the molasses solution is 40-60%, preferably 45-55%, and more preferably 50%;

[0039] The reagent used to adjust the pH is preferably sodium hydroxide.

[0040] In the present invention, the temperature of the reaction is 70-80°C, preferably 72-78°C, and more preferably 75°C; the reaction time is 1-3 h, preferably 1.5-2.5 h, and more preferably 2 h.

[0041] In the present invention, the temperature of the drying is 50-70°C, preferably 55-65°C, and more preferably 60°C.

[0042] In the present invention, both 2-methylvaleric acid and cinnamyl propionate in the combined grinding aid are harmless substances, which will not cause adverse health effects to operators during the grinding process, nor will they affect the safety of the subsequent industrial products.

[0043] In the present invention, adding 2-methylvaleric acid and cinnamyl propionate on the basis of sodium hexametaphosphate also has a good improvement effect on the grinding of quartz. Based on this discovery, through in-depth research, the inventor found that after adding alkalized molasses, the content of particles with a particle size of -0.043 mm during the grinding of quartz can be greatly increased, and it also helps to improve the subsequent flotation recovery rate.

[0044] The present invention provides a preparation method of a combined grinding aid, which is to mix sodium hexametaphosphate, 2-methylvaleric acid, cinnamyl propionate and alkalized molasses.

[0045] The present invention also provides an application of the combined grinding aid in the pretreatment of quartz before flotation of quartz.

[0046] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0047] The sodium hexametaphosphate used in the examples of the present invention is industrial grade, with an active ingredient content of 68%, purchased from Qingzhou Xinsheng Chemical Co., Ltd.; 2-methylvaleric acid is purchased from Sigma-Aldrich; cinnamyl propionate is purchased from Wuhan Karnos Technology Co., Ltd.; beet molasses is purchased from Beijing Silver Angel International Trade Co., Ltd.; quartz is purchased from Guangxi Shiling Building Materials Co., Ltd., with a SiO2 content of 99.6% w / w, and the particle size distribution is: the content of -1.6 ± 0.9 mm is 71.4% w / w, the content of -0.9 ± 0.85 mm is 24.1% w / w, and the content of -0.85 ± 0.45 mm is 4.5% w / w.

[0048] Example 1

[0049] Add beet molasses to distilled water to make a solution with a weight fraction of 50%. Dropwise add sodium hydroxide to adjust the pH to 13, and then react at 75°C for 2 h. After the reaction, dry and grind the product at 60°C to obtain alkalized molasses. Mix 25 parts of sodium hexametaphosphate, 7 parts of 2-methylvaleric acid, 4 parts of cinnamyl propionate, and 4 parts of alkalized molasses evenly to obtain a combined grinding aid.

[0050] Use the combined grinding aid prepared in Example 1 to pretreat quartz before flotation. The specific steps are as follows: Mix 233.0 g of quartz, 50 mL of water, and the combined grinding aid. The addition amount of the combined grinding aid is 0.01% of the weight of quartz, and then add 100 mL of water. Then add it to a ball mill (the ball mill uses steel balls as the medium, and the medium size and weight ratio are set as Φ30 mm: Φ20 mm: Φ15 mm = 30:25:45. Use a 1 L volume ball mill with a specification of Φ150 mm × 50 mm as the experimental equipment, and the medium filling rate is 40%) for grinding. The grinding time is 30 min, and then mechanical screening can be carried out.

[0051] Example 2

[0052] Compared with Example 1, the difference is that in Example 2, 20 parts of sodium hexametaphosphate, 6 parts of 2-methylvaleric acid, 5 parts of cinnamyl propionate, and 3 parts of alkalized molasses are mixed evenly to obtain a combined grinding aid.

[0053] Example 3

[0054] Compared with Example 1, the difference is that in Example 3, 30 parts of sodium hexametaphosphate, 8 parts of 2-methylvaleric acid, 3 parts of cinnamyl propionate, and 5 parts of alkalized molasses are mixed evenly to obtain a combined grinding aid.

[0055] Comparative Example 1

[0056] Compared with Example 1, the difference is that in Comparative Example 1, alkalized molasses is not added.

[0057] Comparative Example 2

[0058] Compared with Example 1, the difference is that in Comparative Example 2, 2-methylvaleric acid and alkalized molasses are not added.

[0059] Comparative Example 3

[0060] Compared with Example 1, the difference is that in Comparative Example 3, 15 parts of alkalized molasses are added.

[0061] Comparative Example 4

[0062] Compared with Example 1, the difference is that in Comparative Example 4, untreated beet molasses is added.

[0063] Comparative Example 5

[0064] Compared with Example 1, in Comparative Example 5, sodium hexametaphosphate was used as a grinding aid to pretreat quartz before flotation of quartz.

[0065] Weighed and mechanically screened Examples 1 to 3 and Comparative Examples 1 to 5, and calculated the content (weight percentage) of the -0.043 mm particle size fraction. The results are shown in Table 1.

[0066] Table 1 Results of the content of the -0.043 mm particle size fraction in Examples 1 to 3 and Comparative Examples 1 to 5

[0067]

[0068]

[0069] As can be seen from Table 1, from the experimental data of Comparative Example 1, Comparative Example 2 and Comparative Example 5, 2-methylvaleric acid and cinnamyl propionate have an enhancing effect on the grinding efficiency of sodium hexametaphosphate on quartz, and the two have a synergistic effect. According to Comparative Examples 1 to 2, when 2-methylvaleric acid was absent, the content of the -0.043 mm particle size fraction decreased to 52.0%. In addition, although the content data of Comparative Example 2 is lower than that of Comparative Example 5, the addition content of the grinding aid is much lower than that of Comparative Example 5, indicating that cinnamyl propionate also has a good enhancing effect on the grinding efficiency of sodium hexametaphosphate on quartz.

[0070] From Comparative Examples 3 to 4, it can be seen that the addition amount of alkalized honey and the alkalization treatment of honey have a significant impact on the grinding efficiency of quartz. By appropriately adding alkalized honey and combining with 2-methylvaleric acid, cinnamyl propionate and sodium hexametaphosphate, the content of the -0.043 mm particle size fraction after grinding can be significantly increased to more than 85%, and the addition amount of the combined grinding aid used is very small, only 0.01% of the weight of quartz.

[0071] It can be seen from this that the combined grinding aid obtained in the present invention has a very good effect on the grinding efficiency of quartz, not only has a small addition amount, but also can significantly increase the content of the -0.043 mm particle size fraction.

[0072] The ground quartz obtained in Example 1 was used for flotation, and the quartz obtained by grinding without using a grinding aid in Reference Example 1 was used as a control group. The flotation machine was a hanging trough flotation machine. The flotation scheme was as follows: Weigh 5 g of ground quartz powder, place it in a 50 mL flotation cell, add distilled water and adjust the pulp, adjust the pH to 11.5, add the collector sodium oleate (addition amount: 150 mg / L) and the activator calcium chloride (addition amount: 80 mg / L), stir for 3 minutes and float and scrape foam for 5 minutes. The flotation foam product and the product in the cell were filtered, dried and weighed respectively, and the flotation recovery rate was calculated. The results are shown in Table 2.

[0073] Table 2 Calculation results of the flotation recovery rates of Example 1 and the control group

[0074] Flotation object Quartz recovery rate (%) Quartz powder obtained in Example 1 95.7 Quartz powder obtained in the control group 91.5

[0075] As can be seen from Table 2, for the quartz powder obtained by grinding with the combined grinding aid of the present invention, the flotation recovery rate can be increased by 4.2 percentage points during flotation.

[0076] As can be seen from the above embodiments, the present invention provides a combined grinding aid and its preparation method and application. The combined grinding aid comprises the following raw materials in parts by weight: 20-30 parts of sodium hexametaphosphate, 6-8 parts of 2-methylvaleric acid, 3-5 parts of cinnamyl propionate, and 3-5 parts of alkalized molasses. The combined grinding aid obtained by the present invention can greatly improve the grinding efficiency of quartz, and the content of -0.043mm particle size can reach more than 85%. Moreover, the dosage of the grinding aid is very low, having good economy; at the same time, after grinding with the combined grinding aid of the present invention, the recovery rate of subsequent flotation of quartz can be improved.

[0077] The above are only the preferred embodiments of the present invention. It should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A combined grinding aid, characterized in that, It comprises the following raw materials in parts by weight: 20 - 30 parts of sodium hexametaphosphate, 6 - 8 parts of 2 - methylvaleric acid, 3 - 5 parts of cinnamyl propionate, 3 - 5 parts of alkalized molasses.

2. The combined grinding aid according to claim 1, wherein It comprises the following raw materials in parts by weight: 25 parts of sodium hexametaphosphate, 7 parts of 2 - methylvaleric acid, 4 parts of cinnamyl propionate, and 4 parts of alkalized molasses.

3. The combined grinding aid according to claim 1 or 2, characterized in that, The molasses used for the alkalized molasses includes beet molasses.

4. The combined grinding aid according to claim 3, characterized in that, The preparation method of the alkalized molasses is as follows: Mix molasses and water to obtain a molasses solution, adjust the pH to 11 - 13, then carry out a reaction, and after the reaction is completed, dry it to obtain the product.

5. The combined grinding aid according to claim 4, characterized in that, The mass fraction of the molasses solution is 40 - 60%; The reagent used for adjusting the pH is sodium hydroxide.

6. The combined grinding aid according to claim 5, wherein, The temperature of the reaction is 70 - 80 °C, and the reaction time is 1 - 3 h.

7. The combined grinding aid according to claim 5 or 6, characterized in that, The drying temperature is 50 - 70 °C.

8. A preparation method of the combined grinding aid according to any one of claims 1 to 7, characterized in that, Mix sodium hexametaphosphate, 2 - methylvaleric acid, cinnamyl propionate, and alkalized molasses.

9. Application of the combined grinding aid according to any one of claims 1 - 7 in the pretreatment of quartz before flotation of quartz.

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