Application of TH-904 dispersing agent and rare earth ore flotation method

Abstract

The invention discloses application of a TH-904 dispersing agent and a flotation method of rare earth ore. The TH-904 dispersing agent is used for separating rare earth and gangue minerals in rare earth ore, and the obtained rare earth ore concentrate is higher in REO content and lower in impurity content.

Description

Technical Field

[0001] The present invention relates to the application of TH-904 dispersant and a flotation method of rare earth ore. Background Art

[0002] Rare earth flotation is a key technology for extracting rare earth resources from minerals such as bastnaesite and monazite. Separation is accomplished through the synergistic effect of flotation equipment and flotation reagents (such as inhibitors, collectors, and frothers). The addition of inhibitors, dispersants, collectors, and other flotation reagents can enhance the differences in hydrophilicity and hydrophobicity between minerals, improving flotation process performance. The primary gangue minerals in rare earth ores that float easily but are difficult to separate are fluorite, dolomite, and apatite. In practice, water glass is primarily used to suppress these gangue minerals, resulting in high levels of impurities such as calcium and phosphorus in the rare earth concentrates obtained through flotation.

[0003] CN102319631A discloses a method for flotation of rare earths from Bayan Obo tailings. The tailings are ground to a particle size of -200 mesh, representing at least 95%. The ground tailings are then slurried and subjected to flotation, which includes roughing, cleaning, and scavenging. The agents used are water glass as an inhibitor, hydroxamic acid as a collector, and No. 2 oil or 318# as a frother. The concentrate produced by this patented method is less effective in removing non-rare earth impurities.

[0004] CN101444761A discloses a flotation separation method for a monazite-rich bastnaesite mixed rare earth ore, comprising the following steps: 1) grinding; 2) roughing: the ore pulp after slurry treatment is fed into a flotation device, water glass, a hydroxamic acid collector and a frother are added for roughing, thereby obtaining a primary roughing tailing and a primary roughing concentrate, respectively; 3) scavenging; and 4) concentrating: water is added to the primary roughing concentrate for mixing and slurrying, the roughing concentrate pulp after slurry treatment is fed into a flotation device, water glass inhibitor, a hydroxamic acid collector and a frother are added for concentrating, and the obtained secondary concentrating concentrate is used as the final flotation product. However, the impurity content in the obtained concentrate is relatively high. Summary of the Invention

[0005] In view of this, an object of the present invention is to provide an application of TH-904 dispersant in separating rare earth and gangue minerals in rare earth ores, which can increase the REO content of rare earth concentrate and reduce the content of impurity elements.

[0006] Another object of the present invention is to provide a flotation method for rare earth ores, wherein the rare earth concentrate obtained by the flotation method has a high REO content and a low impurity content.

[0007] The present invention adopts the following technical solutions to achieve the above-mentioned purpose.

[0008] In one aspect, the present invention provides a use of a TH-904 dispersant in separating rare earth and gangue minerals in rare earth ores.

[0009] According to the application provided by the present invention, preferably, the rare earth ore contains one or more of fluorocarbon cerium ore and monazite; the gangue mineral is selected from one or more of fluorite, apatite, iron minerals, barite, nepheline, amphibole, and dolomite.

[0010] According to the application provided by the present invention, preferably, TH-904 dispersant is used in the form of TH-904 dispersant aqueous solution with a concentration of 0.2-5 wt%; for each flotation process, the amount of TH-904 dispersant aqueous solution is 5-400 g / ton of rare earth ore.

[0011] On the other hand, the present invention provides a flotation method for rare earth ore, characterized in that it comprises the following steps:

[0012] Step (1): slurrying the rare earth ore to obtain rare earth ore slurry; performing roughing flotation on the rare earth ore slurry in the presence of TH-904 dispersant, water glass, a collector and a frother to obtain a roughing concentrate and a roughing tailing;

[0013] Step (2): grinding the rougher concentrate to obtain a ground rougher concentrate;

[0014] Step (3): slurrying the ground rougher concentrate to obtain a ground rougher concentrate slurry; performing a first concentration on the ground rougher concentrate slurry in the presence of a TH-904 dispersant, water glass, a collector, and a frother to obtain a first concentrated concentrate and a first concentrated tailings;

[0015] Step (4): the first concentrated concentrate is subjected to a second concentration in the presence of TH-904 dispersant, water glass, a collector and a frother to obtain a second concentrated concentrate and a second concentrated tailing; and similarly, the N-1th concentrated concentrate is subjected to an Nth concentration in the presence of TH-904 dispersant, water glass, a collector and a frother to obtain an Nth concentrated concentrate and an Nth concentrated tailing; wherein N is an integer greater than 2;

[0016] Step (5): Combine the tailings from the first to the Nth round of cleaning and return to step (1) to continue roughing flotation.

[0017] According to the flotation method provided by the present invention, preferably, in step (1), after adding TH-904 dispersant and water glass to the rare earth ore pulp in sequence, the pH value is adjusted to 8-10, and then the collector and frother are added in sequence;

[0018] In step (3), TH-904 dispersant and water glass are added to the grinding roughing concentrate slurry in sequence, the pH value is adjusted to 8-10, and then a collector and a foaming agent are added in sequence;

[0019] In step (4), after adding TH-904 dispersant and water glass to the first concentrated ore, the pH value is adjusted to 8-10, and then a collector and a frother are added in sequence; and so on, after adding TH-904 dispersant and water glass to the N-1th concentrated ore, the pH value is adjusted to 8-10, and then a collector and a frother are added in sequence.

[0020] According to the flotation method provided by the present invention, preferably, the TH-904 dispersant is used in the form of a TH-904 dispersant aqueous solution; the concentration of the TH-904 dispersant aqueous solution is 0.2-5wt%; the concentration of water glass is 2-12wt%; the collector is selected from one or more of salicylic acid, benzoic acid, naphthoic acid, collector P8 or collector 506E; and the foaming agent is selected from one or more of No. 2 oil and methyl isobutyl carbinol.

[0021] According to the flotation method provided by the present invention, preferably, the collector is used in the form of a collector saponified solution formed after saponification; the concentration of the collector saponified solution is 0.05 to 8 wt%;

[0022] The collector saponification solution is prepared by the following method:

[0023] Mixing a collector, sodium hydroxide and water; wherein the mass ratio of the collector to the sodium hydroxide is 1:(0.03-0.8).

[0024] According to the flotation method provided by the present invention, preferably, in step (1), the amount of TH-904 dispersant aqueous solution is 50-400 g / ton of rare earth ore; the amount of water glass is 800-2500 g / ton of rare earth ore; the amount of collector saponify solution is 400-2000 g / ton of rare earth ore; and the amount of frother is 80-280 g / ton of rare earth ore.

[0025] According to the flotation method provided by the present invention, preferably, in step (3), the amount of TH-904 dispersant aqueous solution is 50-400 g / ton of rare earth ore; the amount of water glass is 50-500 g / ton of rare earth ore; the amount of collector saponify solution is 100-400 g / ton of rare earth ore; and the amount of frother is 30-80 g / ton of rare earth ore.

[0026] According to the flotation method provided by the present invention, preferably, in step (4), the dosage of the TH-904 dispersant aqueous solution is 30-100 wt% of the dosage of the TH-904 dispersant in the previous cleaning; the dosage of water glass is 40-100 wt% of the dosage of water glass in the previous cleaning; the dosage of the collector saponification solution is 35-85 wt% of the dosage of the collector saponification solution in the previous cleaning; the dosage of the foaming agent is 30-100 wt% of the dosage of the foaming agent in the previous cleaning.

[0027] The present invention uses the TH-904 dispersant to separate rare earths and gangue minerals in rare earth ore. This can increase the REO content of rare earth concentrate and also reduce the content of impurity elements (such as Ca and P) in rare earth concentrate. Detailed implementation manners

[0028] The following further illustrates the present invention with specific examples, but the protection scope of the present invention is not limited thereto.

[0029] <Application of TH-904 Dispersant>

[0030] The present invention unexpectedly discovers that the TH-904 dispersant can be used to separate rare earths and gangue minerals in rare earth ore.

[0031] The TH-904 dispersant is a colorless to light yellow transparent liquid with a solid content of 40-50 wt%. The TH-904 dispersant is usually used for waterborne scale inhibition, and there is no report on its use for rare earth flotation of rare earth ore. The present invention first proposes to use the TH-904 dispersant to separate rare earths and gangue minerals in rare earth ore. Therefore, the present invention provides an application of the TH-904 dispersant in separating rare earths and gangue minerals in rare earth ore. The process of separating rare earths and gangue minerals in rare earth ore is mainly a flotation process.

[0032] According to an embodiment of the present invention, the rare earth ore is an iron ore tailing.

[0033] The rare earth ore contains one or more of bastnasite and monazite.

[0034] The content of bastnasite can be 10-30 wt%, preferably 13-25 wt%, more preferably 15-20 wt%. The content of monazite can be 5-20 wt%, preferably 7-15 wt%, more preferably 8-12 wt%.

[0035] The gangue minerals contained in the rare earth ore are selected from one or more of fluorite, apatite, iron minerals, barite, aegirine, amphibole, and dolomite.

[0036] In the present invention, the iron minerals are magnetite and hematite.

[0037] In the rare earth ore, the content of magnetite and hematite may be 10 to 30 wt%, preferably 15 to 25 wt%, and more preferably 18 to 22 wt%.

[0038] In the rare earth ore, the content of amphibole may be 1.5 to 7 wt%, preferably 2.5 to 5.5 wt%, and more preferably 3.2 to 5 wt%.

[0039] In the rare earth ore, the content of aegirine may be 4 to 15 wt%, preferably 5 to 10 wt%, and more preferably 6.5 to 9.1 wt%.

[0040] The content of fluorite in the rare earth ore may be 5 to 15 wt%, preferably 7 to 13 wt%, and more preferably 8 to 12 wt%.

[0041] The content of apatite in the rare earth ore may be 1 to 7 wt%, preferably 2 to 5 wt%, and more preferably 2.4 to 4.5 wt%.

[0042] The content of barite in the rare earth ore may be 5 to 15 wt %, preferably 8 to 12 wt %, and more preferably 8.7 to 11 wt %.

[0043] In the rare earth ore, the content of dolomite may be 1.2 to 8 wt%, preferably 2.2 to 5.5 wt%, and more preferably 2.7 to 4.5 wt%.

[0044] The rare earth ore contains REO, CaO, and P2O5; preferably, the rare earth ore contains REO, CaO, P2O5, TFe, and F.

[0045] The content of REO may be 5 to 13 wt%, preferably 6 to 10 wt%, and more preferably 7 to 9.5 wt%. The content of CaO may be 15 to 30 wt%, preferably 18 to 26 wt%, and more preferably 20 to 24 wt%. The content of P2O5 may be 1 to 6 wt%, preferably 2 to 5 wt%, and more preferably 2.5 to 4.5 wt%. The content of TFe may be 6 to 17 wt%, preferably 8 to 15 wt%, and more preferably 9.5 to 13 wt%. The content of F may be 7 to 14 wt%, preferably 8 to 12 wt%, and more preferably 9 to 11.5 wt%.

[0046] TH-904 dispersant can be used for roughing and / or cleaning of rare earth flotation. Adding TH-904 dispersant to flotation can make the rare earth concentrate with higher REO content and lower impurity content.

[0047] The TH-904 dispersant can be used in the form of an aqueous solution of the TH-904 dispersant. The concentration of the aqueous solution of the TH-904 dispersant can be 0.2 to 5 wt %, preferably 0.2 to 4 wt %, and more preferably 0.5 to 2 wt %.

[0048] The flotation process may include multiple flotation steps. In each flotation step, the amount of TH-904 dispersant aqueous solution used is 5 to 400 g per ton of rare earth ore, preferably 15 to 300 g per ton of rare earth ore, more preferably 15 to 250 g per ton of rare earth ore, and even more preferably 20 to 200 g per ton of rare earth ore.

[0049] The flotation process includes the following steps: roughing, grinding, first cleaning, second to Nth cleaning, and tailings re-cleaning. The specific steps are the same as those described in <Flotation Method> and will not be repeated here.

[0050] <Flotation method>

[0051] In the present invention, the flotation method of rare earth ore includes the following steps: a roughing step, a grinding step, a first concentration step, a second to Nth concentration step, and a concentrated tailings re-selection step.

[0052] Rough selection step

[0053] The rare earth ore is slurried to obtain rare earth ore slurry; the rare earth ore slurry is subjected to roughing in the presence of TH-904 dispersant, water glass, a collector and a foaming agent to obtain roughing concentrate and roughing tailings.

[0054] The concentration of the rare earth ore slurry may be 45 to 65 wt%, preferably 50 to 60 wt%, and more preferably 53 to 57 wt%.

[0055] The rare earth ore slurry is heated before roughing flotation. Specifically, the rare earth ore slurry is heated to a temperature of 50-90°C, preferably 55-85°C, and more preferably 55-65°C. In some embodiments, the rare earth ore slurry is heated to a temperature of 75-85°C. This results in a rare earth concentrate with a higher REO content and lower impurities.

[0056] After adding TH-904 dispersant and water glass to the rare earth ore slurry in sequence, the pH value is adjusted to 8-10, and then the collector and foaming agent are added in sequence.

[0057] TH-904 dispersant can be used in the form of an aqueous solution. The aqueous solution is prepared by mixing TH-904 dispersant with water. The concentration of the aqueous solution can range from 0.2 to 5 wt%, preferably from 0.2 to 4 wt%, and more preferably from 1.5 to 2 wt%. In rougher flotation, the addition of TH-904 dispersant can increase the REO content and reduce the impurity content of the resulting rare earth concentrate.

[0058] The concentration of water glass may be 2 to 12 wt %, preferably 3 to 10 wt %, and more preferably 4 to 8 wt %.

[0059] The pH is adjusted using a pH adjuster. The pH adjuster is an aqueous sulfuric acid solution or an aqueous sodium hydroxide solution. The concentration of the pH adjuster is 1 to 10 wt %, preferably 3 to 8 wt %, and more preferably 4 to 7 wt %. The pH is adjusted to 9 to 10; preferably, the pH is adjusted to 9.3 to 9.7, and more preferably, the pH is adjusted to 9.4 to 9.6.

[0060] The collector is selected from one or more of salicylic acid, benzoic acid, naphthoic acid, collector P8 or collector 506E; preferably, the collector is selected from one or more of collector P8 or collector 506E.

[0061] The foaming agent can be selected from one or more of No. 2 oil and methyl isobutyl carbinol. The rare earth concentrate obtained by using collector 506E as a collector can increase the content of REO while maintaining the impurity content.

[0062] The collector is used in the form of a collector saponified solution formed after saponification. The concentration of the collector saponified solution is 0.05 to 8 wt%, preferably 1 to 6 wt%, and more preferably 1.5 to 4 wt%.

[0063] The collector saponification solution is prepared by mixing the collector, sodium hydroxide, and water. The mass ratio of the collector to sodium hydroxide can be 1:(0.03-0.8), preferably 1:(0.03-0.6), and more preferably 1:(0.07-0.4).

[0064] The dosage of the TH-904 dispersant aqueous solution can be 50-400 g / ton of rare earth ore, preferably 75-300 g / ton of rare earth ore, more preferably 80-220 g / ton of rare earth ore, further preferably 90-180 g / ton of rare earth ore, more preferably 100-135 g / ton of rare earth ore.

[0065] The amount of water glass used can be 800-2500 g / ton of rare earth ore, preferably 1000-2000 g / ton of rare earth ore, more preferably 1200-1700 g / ton of rare earth ore, and further preferably 1300-1600 g / ton of rare earth ore.

[0066] The amount of the collector saponified solution used can be 400-2000 g / ton of rare earth ore, preferably 500-1500 g / ton of rare earth ore, more preferably 600-1200 g / ton of rare earth ore, and further preferably 900-1100 g / ton of rare earth ore.

[0067] The dosage of the foaming agent is 80-280 g / ton of rare earth ore, preferably 120-250 g / ton of rare earth ore, more preferably 130-200 g / ton of rare earth ore, and further preferably 170-190 g / ton of rare earth ore.

[0068] Grinding steps

[0069] The rougher concentrate is ground to obtain a ground rougher concentrate. Adding the grinding step can make the rare earth concentrate obtained by flotation have a higher REO content and lower impurity (such as Ca and P) content.

[0070] The grinding equipment is selected from a ceramic ball mill or a stirred mill; the grinding medium is selected from agate balls, corundum balls, or zirconia balls; preferably, the grinding medium is zirconia balls. The volume filling rate of the grinding can be 35-45%, preferably 37-43%, and more preferably 38-42%.

[0071] The content of particles below 38 μm obtained after grinding accounts for 85-94%, preferably 86-92%, and more preferably 87-90%.

[0072] 1st selection

[0073] The grinding rougher concentrate is slurried to obtain grinding rougher concentrate slurry; the grinding rougher concentrate slurry is subjected to a first concentration in the presence of TH-904 dispersant, water glass, a collector and a frother to obtain a first concentrated concentrate and a first concentrated tailings.

[0074] The concentration of the grinding rougher concentrate slurry is 30-55 wt%, preferably 40-50 wt%, and more preferably 43-47 wt%.

[0075] The first round of concentration is performed after heating the grinding rougher concentrate slurry. Specifically, the grinding rougher concentrate slurry is heated to 50-90°C, preferably 55-85°C, and more preferably 55-65°C. In some embodiments, the grinding rougher concentrate slurry is heated to 75-85°C. This results in a rare earth concentrate with a higher REO content and lower impurities.

[0076] After adding TH-904 dispersant and water glass to the grinding rougher concentrate slurry, the pH value is adjusted to 8-10, and then the collector and frother are added in sequence. Adding TH-904 dispersant can increase the REO content of the produced rare earth concentrate and reduce the impurity content.

[0077] The selection of TH-904 dispersant, water glass, and collector, except for the dosage, and the pH adjustment method are as described above and will not be repeated here.

[0078] The dosage of the TH-904 dispersant aqueous solution can be 50-400 g / ton of rare earth ore, preferably 70-250 g / ton of rare earth ore, more preferably 80-180 g / ton of rare earth ore, and further preferably 120-145 g / ton of rare earth ore.

[0079] The amount of water glass used can be 50-500 g / ton of rare earth ore, preferably 80-400 g / ton of rare earth ore, more preferably 100-300 g / ton of rare earth ore, and further preferably 230-270 g / ton of rare earth ore.

[0080] The amount of the collector saponified solution used can be 100-400 g / ton of rare earth ore, preferably 120-350 g / ton of rare earth ore, more preferably 130-250 g / ton of rare earth ore, and further preferably 180-230 g / ton of rare earth ore.

[0081] The dosage of the foaming agent can be 30-80 g / ton of rare earth ore, preferably 35-70 g / ton of rare earth ore, more preferably 40-65 g / ton of rare earth ore, and further preferably 50-65 g / ton of rare earth ore.

[0082] Steps for the 2nd to Nth rounds of selection

[0083] The first concentrated concentrate is subjected to a second concentration in the presence of TH-904 dispersant, water glass, a collector and a frother to obtain a second concentrated concentrate and a second concentrated tailing; and similarly, the N-1th concentrated concentrate is subjected to an Nth concentration in the presence of TH-904 dispersant, water glass, a collector and a frother to obtain an Nth concentrated concentrate and an Nth concentrated tailing; wherein N is an integer greater than 2; preferably, N is selected from an integer of 3 to 8; more preferably, N is selected from an integer of 3 to 5; in some embodiments, N is 3, 4, 5, 6, 7 or 8.

[0084] In the present invention, the Nth concentrated ore is the rare earth concentrate.

[0085] To the first concentrated ore, TH-904 dispersant and water glass are added in sequence, the pH value is adjusted to 8-10, and then a collector and a frother are added in sequence; and so on, to the N-1th concentrated ore, TH-904 dispersant and water glass are added in sequence, the pH value is adjusted to 8-10, and then a collector and a frother are added in sequence.

[0086] The selection of TH-904 dispersant, water glass, and collector, except for the dosage, and the pH adjustment method are as described above and will not be repeated here.

[0087] The amount of the TH-904 dispersant aqueous solution used is 30 to 100 wt % of the amount of TH-904 dispersant used in the previous concentration, preferably 40 to 80 wt % of the amount of TH-904 dispersant used in the previous concentration, more preferably 50 to 70 wt % of the amount of TH-904 dispersant used in the previous concentration, and even more preferably 50 to 60 wt % of the amount of TH-904 dispersant used in the previous concentration. Adding the TH-904 dispersant can increase the REO content of the prepared rare earth concentrate and reduce the impurity content.

[0088] The amount of water glass used is 40 to 100 wt % of the amount of water glass used in the last selection, preferably 40 to 90 wt % of the amount of water glass used in the last selection, and more preferably 50 to 80 wt % of the amount of water glass used in the last selection.

[0089] The amount of the collector saponify solution used is 35-85wt% of the amount of the collector saponify solution used in the previous selection, preferably 40-80wt% of the amount of the collector saponify solution used in the previous selection, and more preferably 45-75wt% of the amount of the collector saponify solution used in the previous selection.

[0090] The amount of the foaming agent used is 30-100 wt % of the amount of the foaming agent used in the previous selection, preferably 40-70 wt % of the amount of the foaming agent used in the previous selection, and more preferably 50-65 wt % of the amount of the foaming agent used in the previous selection.

[0091] Re-selection steps of tailings

[0092] The tailings from the first to the Nth round of concentration are combined and returned to the roughing step to continue the roughing flotation.

[0093] The raw materials used in the following examples and comparative examples are introduced below:

[0094] Rare earth ore: Iron tailings obtained from magnetic separation of Bayan Obo ore. The main components of the rare earth ore are as follows: 17.53wt% bastnaesite, 9.94wt% monazite, 19.45wt% hematite, 4.19wt% amphibole, 7.95wt% nepheline, 10.98wt% fluorite, 3.47wt% apatite, 9.78wt% barite, and 3.36wt% dolomite. The mass percentages of the rare earth ore are: 8.57wt% REO, 22.51wt% CaO, 3.45wt% P2O5, 11.68wt% TFe, and 10.26wt% F.

[0095] TH-904 dispersant: produced by Shandong Taihe Co., Ltd., is a colorless to light yellow transparent liquid with a solid content of 45wt%.

[0096] Sulfuric acid aqueous solution: 5 wt% sulfuric acid aqueous solution.

[0097] Water glass: The concentration is 4wt% water glass.

[0098] Collector P8 saponify solution: Collector P8 (produced by Inner Mongolia Baotou Steel Rare Earth Linfeng Technology Co., Ltd.) and sodium hydroxide are mixed in a mass ratio of 1:0.15, and water is added to prepare a P8 saponify solution with a mass concentration of 2 wt%.

[0099] Collector 506E saponified solution: Collector 506E (produced by Baotou Mengrong Fine Materials Co., Ltd.) and sodium hydroxide were mixed in a mass ratio of 1:0.15, and water was added to prepare a 506E saponified solution with a mass concentration of 2 wt%.

[0100] No. 2 oil was purchased from Baotou Pengde Trading Co., Ltd.

[0101] Example 1

[0102] The TH-904 dispersant was dissolved in water to obtain a TH-904 dispersant aqueous solution with a concentration of 1 wt%.

[0103] The rare earth ore was added with water for slurry preparation, and the mixture was heated to 80° C. to obtain a rare earth ore slurry with a concentration of 58 wt %.

[0104] A TH-904 dispersant aqueous solution was added to the rare earth ore slurry and stirred for 5 minutes; then, water glass was added and stirred for 5 minutes; then, a sulfuric acid aqueous solution was used to adjust the pH value to 9.5; a collector P8 saponified solution was added and stirred for 5 minutes; then, No. 2 oil was added and stirred for 3 minutes, and roughing flotation operations were carried out to obtain roughing concentrate and roughing tailings.

[0105] The rougher concentrate is ground in a ceramic ball mill (using zirconia balls as the medium) with a volume filling rate of 40%, and the grinding fineness is reduced to 90wt% of particles below 38μm, thereby obtaining a ground rougher concentrate.

[0106] The grinding rougher concentrate was slurried with water and heated to 80°C to obtain a grinding rougher concentrate slurry with a concentration of 43 wt%. An aqueous solution of TH-904 dispersant was added to the grinding rougher concentrate slurry and stirred for 5 minutes. Then, water glass was added and stirred for 5 minutes. The pH value was adjusted to 9.5 with an aqueous sulfuric acid solution. A saponified solution of collector P8 was added and stirred for 5 minutes. Finally, No. 2 oil was added and stirred for 3 minutes before the first concentrating operation was performed to obtain the first concentrating concentrate and the first concentrating tailings.

[0107] Add TH-904 dispersant aqueous solution to the first concentrated concentrate and stir for 5 minutes; then add water glass and stir for 5 minutes; then adjust the pH value to 9.5 with sulfuric acid aqueous solution; then add collector P8 saponify solution and stir for 5 minutes; then add No. 2 oil and stir for 3 minutes before performing the second concentration operation to obtain the second concentrated concentrate and the second concentrated tailings.

[0108] Add TH-904 dispersant aqueous solution to the second beneficiation concentrate and stir for 5 minutes; then add water glass and stir for 5 minutes; then add sulfuric acid aqueous solution to adjust the pH value to 9.5; then add collector P8 saponified solution and stir for 5 minutes; then add No. 2 oil and stir for 3 minutes before performing the third beneficiation operation to obtain rare earth concentrate and third beneficiation tailings;

[0109] The tailings from the first to third rounds of concentration are combined and returned to the roughing flotation operation for re-selection.

[0110] The following table shows the dosage of components in each flotation step per ton of rare earth ore.

[0111] Table 1

[0112]

[0113] Example 2

[0114] The TH-904 dispersant was dissolved in water to obtain a 1.5 wt % TH-904 dispersant aqueous solution.

[0115] The rare earth ore was added with water for slurry preparation, and the mixture was heated to 60° C. to obtain a rare earth ore slurry with a concentration of 55 wt %.

[0116] Add TH-904 dispersant aqueous solution to the rare earth ore slurry and stir for 5 minutes; then add water glass and stir for 5 minutes; then add sulfuric acid aqueous solution to adjust the pH value to 9.5; add collector P8 saponified solution and stir for 5 minutes; then add No. 2 oil and stir for 3 minutes, and perform roughing flotation operation to obtain roughing concentrate and roughing tailings.

[0117] The rougher concentrate is ground in a ceramic ball mill (the medium is zirconia balls) with a volume filling rate of 40%, and the content of the ground ore with a fineness of less than 38 μm accounts for 88wt%, thereby obtaining a ground rougher concentrate.

[0118] The grinding rougher concentrate was slurried with water and heated to 60°C to obtain a grinding rougher concentrate slurry with a concentration of 45wt%. An aqueous solution of TH-904 dispersant was added to the grinding rougher concentrate slurry and stirred for 5 minutes. Then, water glass was added and stirred for 5 minutes. The pH value was adjusted to 9.5 with an aqueous sulfuric acid solution. A saponified solution of collector P8 was added and stirred for 5 minutes. No. 2 oil was added and stirred for 3 minutes before the first concentrating operation was carried out to obtain the first concentrating concentrate and the first concentrating tailings.

[0119] Add TH-904 dispersant aqueous solution to the first concentrated concentrate and stir for 5 minutes; then add water glass and stir for 5 minutes; then adjust the pH value to 9.5 with sulfuric acid aqueous solution; then add collector P8 saponify solution and stir for 5 minutes; then add No. 2 oil and stir for 3 minutes before performing the second concentration operation to obtain the second concentrated concentrate and the second concentrated tailings.

[0120] Add TH-904 dispersant aqueous solution to the second beneficiation concentrate and stir for 5 minutes; then add water glass and stir for 5 minutes; then adjust the pH value to 9.5 with sulfuric acid aqueous solution; then add collector P8 saponify solution and stir for 5 minutes; then add No. 2 oil and stir for 3 minutes before performing the third beneficiation operation to obtain rare earth concentrate and third beneficiation tailings.

[0121] The tailings from the first to third rounds of concentration are combined and returned to the roughing flotation operation for re-selection.

[0122] Table 2 shows the dosage of components in each flotation step per ton of rare earth ore.

[0123] Table 2

[0124]

[0125]

[0126] Example 3

[0127] The TH-904 dispersant was dissolved in water to obtain a 1.5 wt % TH-904 dispersant aqueous solution.

[0128] The rare earth ore was slurried with water and heated to 60° C. to obtain a rare earth ore slurry with a concentration of 55 wt %.

[0129] A TH-904 dispersant aqueous solution was added to the rare earth ore slurry and stirred for 5 minutes; then, water glass was added and stirred for 5 minutes; then, the pH value was adjusted to 9.5 with a sulfuric acid aqueous solution; then, a collector 506E saponified solution was added and stirred for 5 minutes; then, No. 2 oil was added and stirred for 3 minutes, and then a roughing flotation operation was carried out to obtain a roughing concentrate and a roughing tailing.

[0130] The rougher concentrate is ground in a ceramic ball mill (the medium is zirconia balls) with a volume filling rate of 40%, and the content of the ground ore with a fineness of less than 38 μm accounts for 88wt%, thereby obtaining a ground rougher concentrate.

[0131] The grinding rougher concentrate was slurried with water and heated to 60°C to obtain a grinding rougher concentrate slurry with a concentration of 45 wt%. An aqueous solution of TH-904 dispersant was added to the grinding rougher concentrate slurry and stirred for 5 minutes. Then, water glass was added and stirred for 5 minutes. The pH value was adjusted to 9.5 with an aqueous sulfuric acid solution. A saponified solution of collector 506E was added and stirred for 5 minutes. Finally, No. 2 oil was added and stirred for 3 minutes before the first concentrating operation was performed to obtain the first concentrating concentrate and the first concentrating tailings.

[0132] Add TH-904 dispersant aqueous solution to the first beneficiation concentrate and stir for 5 minutes; then add water glass and stir for 5 minutes; then adjust the pH value to 9.5 with sulfuric acid aqueous solution; then add collector 506E saponified solution and stir for 5 minutes; then add No. 2 oil and stir for 3 minutes before performing the second beneficiation operation to obtain the second beneficiation concentrate and the second beneficiation tailings.

[0133] A TH-904 dispersant aqueous solution was added to the second beneficiation concentrate and stirred for 5 minutes; then, water glass was added and stirred for 5 minutes; then, the pH value was adjusted to 9.5 with a sulfuric acid aqueous solution; then, a collector 506E saponified solution was added and stirred for 5 minutes; then, No. 2 oil was added and stirred for 3 minutes before the third beneficiation operation was carried out to obtain rare earth concentrate and the third beneficiation tailings.

[0134] The tailings from the first to third rounds of concentration are combined and returned to the roughing flotation operation for re-selection.

[0135] Table 3 shows the dosage of components in each flotation step per ton of rare earth ore.

[0136] Table 3

[0137]

[0138] Comparative Example 1

[0139] The only difference from Example 1 is that no TH-904 dispersant aqueous solution is added.

[0140] Comparative Example 2

[0141] The only difference from Example 1 is that the rougher concentrate grinding operation is not performed.

[0142] Comparative Example 3

[0143] The only difference from Example 3 is that no TH-904 dispersant aqueous solution is added.

[0144] Experimental example

[0145] The REO content, Ca content and P content of the rare earth concentrates obtained in the examples and comparative examples were determined using the following determination methods:

[0146] REO content: tested according to the method specified in GB / T 18114.1-2010.

[0147] Ca content: tested according to the method specified in GB / T 18114.3-2010.

[0148] P content: tested according to the method specified in GB / T 18114.9-2010.

[0149] The results are shown in Table 4.

[0150] Table 4

[0151] Serial number REO content / % Ca content / % P content / % Example 1 58.81 2.87 1.55 Example 2 57.86 3.18 2.10 Example 3 60.35 2.96 1.88 Comparative Example 1 55.68 4.98 4.56 Comparative Example 2 56.28 4.61 4.13 Comparative Example 3 56.55 5.85 3.95

[0152] The test results show that, compared with Comparative Examples 1 to 3, Examples 1 and 3, by adding a TH-904 dispersant aqueous solution and increasing the grinding step, can achieve a higher REO content in the rare earth concentrate, and the impurity contents of Ca and P are significantly lower. Compared with Example 2, Example 1, in which the slurry temperature is heated to 80°C during the roughing and first concentrating, produces a rare earth concentrate with a higher REO content and lower impurities. Compared with Example 2, the use of a saponified solution of the collector 506E can achieve a higher REO content in the rare earth concentrate without increasing the impurity content.

[0153] The present invention is not limited to the above-mentioned embodiments. Any modification, improvement, or substitution that can be conceived by those skilled in the art without departing from the essential content of the present invention shall fall within the scope of the present invention.

Claims

1. Application of TH-904 dispersant in separation of rare earth and gangue minerals in rare earth ores.

2. The use according to claim 1, characterized in that The rare earth ore contains one or more of fluorocarbon cerium ore and monazite; the gangue minerals are selected from one or more of fluorite, apatite, iron minerals, barite, nepheline, amphibole and dolomite.

3. The use according to claim 1, characterized in that The TH-904 dispersant is used in the form of a TH-904 dispersant aqueous solution with a concentration of 0.2 to 5 wt%. For each flotation process, the amount of the TH-904 dispersant aqueous solution is 5 to 400 g per ton of rare earth ore.

4. A flotation method for rare earth ores, characterized in that: The steps include: Step (1): slurrying the rare earth ore to obtain rare earth ore slurry; performing roughing flotation on the rare earth ore slurry in the presence of TH-904 dispersant, water glass, a collector and a frother to obtain a roughing concentrate and a roughing tailing; Step (2): grinding the rougher concentrate to obtain a ground rougher concentrate; Step (3): slurrying the ground rougher concentrate to obtain a ground rougher concentrate slurry; performing a first concentration on the ground rougher concentrate slurry in the presence of a TH-904 dispersant, water glass, a collector, and a frother to obtain a first concentrated concentrate and a first concentrated tailings; Step (4): the first concentrated concentrate is subjected to a second concentration in the presence of TH-904 dispersant, water glass, a collector and a frother to obtain a second concentrated concentrate and a second concentrated tailing; and similarly, the N-1th concentrated concentrate is subjected to an Nth concentration in the presence of TH-904 dispersant, water glass, a collector and a frother to obtain an Nth concentrated concentrate and an Nth concentrated tailing; wherein N is an integer greater than 2; Step (5): Combine the tailings from the first to the Nth round of cleaning and return to step (1) to continue roughing flotation.

5. The flotation method according to claim 4, wherein: In step (1), TH-904 dispersant and water glass are sequentially added to the rare earth ore slurry, the pH value is adjusted to 8-10, and then a collector and a foaming agent are sequentially added; In step (3), TH-904 dispersant and water glass are added to the grinding roughing concentrate slurry in sequence, the pH value is adjusted to 8-10, and then a collector and a foaming agent are added in sequence; In step (4), after adding TH-904 dispersant and water glass to the first concentrated ore, the pH value is adjusted to 8-10, and then a collector and a frother are added in sequence; and so on, after adding TH-904 dispersant and water glass to the N-1th concentrated ore, the pH value is adjusted to 8-10, and then a collector and a frother are added in sequence.

6. The flotation method according to claim 4, wherein: The TH-904 dispersant is used in the form of a TH-904 dispersant aqueous solution; the concentration of the TH-904 dispersant aqueous solution is 0.2-5 wt%; the concentration of water glass is 2-12 wt%; the collector is selected from one or more of salicylic acid, benzoic acid, naphthoic acid, collector P8 or collector 506E; and the foaming agent is selected from one or more of No. 2 oil and methyl isobutyl carbinol.

7. The flotation method according to claim 6, characterized in that: The collector is used in the form of a collector saponified solution formed after saponification; the concentration of the collector saponified solution is 0.05 to 8 wt%; The collector saponification solution is prepared by the following method: Mixing a collector, sodium hydroxide and water; wherein the mass ratio of the collector to the sodium hydroxide is 1:(0.03-0.8).

8. The flotation method according to claim 7, characterized in that: In step (1), the amount of TH-904 dispersant aqueous solution is 50 to 400 g per ton of rare earth ore; the amount of water glass is 800 to 2500 g per ton of rare earth ore; the amount of collector saponify solution is 400 to 2000 g per ton of rare earth ore; and the amount of foaming agent is 80 to 280 g per ton of rare earth ore.

9. The flotation method according to claim 7, wherein: In step (3), the amount of TH-904 dispersant aqueous solution is 50-400 g / ton of rare earth ore; the amount of water glass is 50-500 g / ton of rare earth ore; the amount of collector saponify solution is 100-400 g / ton of rare earth ore; and the amount of foaming agent is 30-80 g / ton of rare earth ore.

10. The flotation method according to claim 7, wherein: In step (4), the amount of TH-904 dispersant aqueous solution is 30 to 100 wt% of the amount of TH-904 dispersant used in the previous selection; the amount of water glass is 40 to 100 wt% of the amount of water glass used in the previous selection; the amount of collector saponify solution is 35 to 85 wt% of the amount of collector saponify solution used in the previous selection; and the amount of foaming agent is 30 to 100 wt% of the amount of foaming agent used in the previous selection.

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