A method for comprehensive recovery of low-grade tungsten, molybdenum and bismuth resources

Abstract

The present invention discloses a method for the comprehensive recovery of low-grade tungsten, molybdenum, and bismuth from low-resource materials. The method comprises the following steps: grinding the raw ore to a fineness sufficient to dissociate the basic monomers of the various target minerals before separation, and then flotation-separating the sulfide minerals; obtaining a coarse molybdenum-bismuth concentrate; then utilizing molybdenum's natural floatability to separate the molybdenum and bismuth, and subjecting the sulfide ore tailings to tungsten flotation to obtain a coarse tungsten concentrate. This novel process breaks with conventional thinking by employing the conventional tungsten separation process, the caustic soda method, while increasing the amount of water glass and strengthening the suppression of gangue minerals. This method successfully overcomes the technical difficulties of tungsten separation. By adding a modified hydroxyapatite composite carbon nanotube agent as an auxiliary agent, the process, after modification and optimization, enhances the recovery efficiency of the product raw materials.

Description

Technical Field

[0001] The present invention relates to the technical field of tungsten, molybdenum and bismuth recovery, and in particular to a method for comprehensive recovery of low-grade tungsten, molybdenum and bismuth as a low-resource material. Background Art

[0002] The tungsten, molybdenum, and bismuth polymetallic ore is a large skarn-type polymetallic ore with ore reserves reaching 14 million tons. The ore contains significant reserves of the valuable minerals tungsten, molybdenum, and bismuth, including 26,256 tons of tungsten metal, 8,165 tons of molybdenum metal, and 9,069 tons of bismuth metal, offering significant development prospects. Beginning in January 2010, a beneficiation process for this ore body was piloted. Through these pilot studies, it was determined that the process flow, employing molybdenum-bismuth isofloatation and caustic soda GY flotation, achieved excellent technical performance. Based on theoretical research and pilot tests, a 24-day industrial trial was conducted on the polymetallic ore in July 2010, with a total processing capacity of 9,942 tons. With an ore grade of 0.17% tungsten, 0.063% molybdenum, and 0.07% bismuth, the three concentrates were successfully obtained. To improve the recovery rate, the present invention provides a method for the comprehensive recovery of low-grade tungsten, molybdenum, and bismuth from low-resource sources. Summary of the Invention

[0003] In view of the defects of the prior art, the purpose of the present invention is to provide a method for comprehensive recovery of low-grade tungsten, molybdenum and bismuth resources to solve the problems raised in the above background technology.

[0004] The present invention solves the technical problem by adopting the following technical solutions:

[0005] The present invention provides a method for comprehensive recovery of low-grade tungsten, molybdenum and bismuth resources, comprising the following steps:

[0006] Before the ore enters the sorting process, it is ground to a fineness that allows the basic monomers of various target minerals to dissociate, and then mixed with sulfide minerals for flotation to obtain a rough concentrate of molybdenum and bismuth. The natural floatability of molybdenum is then utilized to separate molybdenum and bismuth. The sulfide tailings are then sent to tungsten flotation to obtain a rough concentrate of tungsten.

[0007] The specific method is: sulfide ore flotation

[0008] Sulfide ore uses soda ash as a pH adjuster, SN-9 as a collector, BK205 as a frother, and mixed flotation tailings as tungsten flotation feed; the output tungsten rough concentrate has a grade of 3.9% and a recovery rate of 81%;

[0009] Tungsten flotation: Mixed flotation tailings are used for the flotation of scheelite and black tungsten. The collectors for the flotation of black scheelite and black scheelite are fatty acids and their soaps, such as oleic acid, sodium oleate, and oxidized paraffin soap. This experiment first explored the flotation of scheelite using the GY method. The flotation adopts a one-coarse-one-fine-one-sweep method, with soda ash as the pH adjuster, water glass aluminum sulfate mixture as the inhibitor, and GY as the collector. The dosage of the reagents is supplemented according to the on-site conditions. The output tungsten rough concentrate has a grade of 3.9% and a recovery rate of 81%.

[0010] Preferably, in the tungsten flotation, modified hydroxyapatite composite carbon nanotube agent is added as an auxiliary agent, wherein the amount of the auxiliary agent added is 5-10% of the collector.

[0011] Preferably, the preparation method of the modified hydroxyapatite composite carbon nanotube agent is:

[0012] S01: Add carbon nanotubes to 2-3 times the volume of sodium alginate solution, then add hydrochloric acid (5-10% of the total volume of carbon nanotubes), and then add chitosan solution and stir evenly;

[0013] S02: Add hydroxyapatite to 4-5 times of sodium dodecyl sulfate solution, stir evenly, and finally add 5-10% of the total amount of hydroxyapatite silane coupling agent KH560 and 1-5% of lanthanum sulfate, stir thoroughly, then wash with water and dry to obtain pre-modified hydroxyapatite;

[0014] S03: Add the hydroxyapatite pre-modified by S02 to 3-5 times the amount of the S01 product, stir and mix evenly, and finally wash with water and dry to obtain a modified hydroxyapatite composite carbon nanotube agent.

[0015] Preferably, the mass fraction of the chitosan solution is 20-25%.

[0016] Preferably, the amount of chitosan solution added is 5-10% of the total amount of carbon nanotubes.

[0017] Preferably, the mass fraction of the sodium alginate solution is 10-20%.

[0018] Preferably, the mass fraction of the sodium alginate solution is 15%.

[0019] Preferably, the mass fraction of the sodium lauryl sulfate solution is 5-10%.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] The present invention conducted a 24-day industrial test on a polymetallic ore, with a total processing capacity of 9,942 tons. With an ore grade of 0.17% tungsten, 0.063% molybdenum, and 0.07% bismuth, three concentrate products, tungsten, molybdenum, and bismuth, were successfully obtained. The scheelite concentrate had a grade of 65.21% and a recovery rate of 68.39%, the molybdenum concentrate had a grade of 43.12% and a recovery rate of 82.49%, and the bismuth concentrate had a grade of 27.10% and a recovery rate of 69.84%. The new process breaks with conventional thinking by not using the conventional tungsten beneficiation process, the soda method, but by increasing the amount of water glass and strengthening the suppression of gangue minerals. This successfully overcomes the technical difficulties of tungsten beneficiation. By adding a modified hydroxyapatite composite carbon nanotube agent as an auxiliary agent, the recovery efficiency of the product raw materials is enhanced after modification and optimization. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the process of the present invention. DETAILED DESCRIPTION

[0023] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0024] A method for comprehensive recovery of low-grade tungsten, molybdenum and bismuth as a low-resource resource in this embodiment includes the following steps:

[0025] Before the ore enters the sorting process, it is ground to a fineness that allows the basic monomers of various target minerals to dissociate, and then mixed with sulfide minerals for flotation to obtain a rough concentrate of molybdenum and bismuth. The natural floatability of molybdenum is then utilized to separate molybdenum and bismuth. The sulfide tailings are then sent to tungsten flotation to obtain a rough concentrate of tungsten.

[0026] The specific method is: sulfide ore flotation

[0027] Sulfide ore uses soda ash as a pH adjuster, SN-9 as a collector, BK205 as a frother, and mixed flotation tailings as tungsten flotation feed; the output tungsten rough concentrate has a grade of 3.9% and a recovery rate of 81%;

[0028] Tungsten flotation: Mixed flotation tailings are used for the flotation of scheelite and black tungsten. The collectors for the flotation of black scheelite and black scheelite are fatty acids and their soaps, such as oleic acid, sodium oleate, and oxidized paraffin soap. This experiment first explored the flotation of scheelite using the GY method. The flotation adopts a one-coarse-one-fine-one-sweep method, with soda ash as the pH adjuster, water glass aluminum sulfate mixture as the inhibitor, and GY as the collector. The dosage of the reagents is supplemented according to the on-site conditions. The output tungsten rough concentrate has a grade of 3.9% and a recovery rate of 81%.

[0029] Preferably, in the tungsten flotation, modified hydroxyapatite composite carbon nanotube agent is added as an auxiliary agent, wherein the amount of the auxiliary agent added is 5-10% of the collector.

[0030] The preparation method of the modified hydroxyapatite composite carbon nanotube agent of this embodiment is as follows:

[0031] S01: Add carbon nanotubes to 2-3 times the volume of sodium alginate solution, then add hydrochloric acid (5-10% of the total volume of carbon nanotubes), and then add chitosan solution and stir evenly;

[0032] S02: Add hydroxyapatite to 4-5 times of sodium dodecyl sulfate solution, stir evenly, and finally add 5-10% of the total amount of hydroxyapatite silane coupling agent KH560 and 1-5% of lanthanum sulfate, stir thoroughly, then wash with water and dry to obtain pre-modified hydroxyapatite;

[0033] S03: Add the hydroxyapatite pre-modified by S02 to 3-5 times the amount of the S01 product, stir and mix evenly, and finally wash with water and dry to obtain a modified hydroxyapatite composite carbon nanotube agent.

[0034] The mass fraction of the chitosan solution in this embodiment is 20-25%.

[0035] The amount of chitosan solution added in this embodiment is 5-10% of the total amount of carbon nanotubes.

[0036] The mass fraction of the sodium alginate solution in this embodiment is 10-20%.

[0037] The mass fraction of the sodium alginate solution in this embodiment is 15%.

[0038] The mass fraction of the sodium lauryl sulfate solution in this embodiment is 5-10%.

[0039] Example 1:

[0040] A method for comprehensive recovery of low-grade tungsten, molybdenum and bismuth as a low-resource resource in this embodiment includes the following steps:

[0041] Before the ore enters the sorting process, it is ground to a fineness that allows the basic monomers of various target minerals to dissociate, and then mixed with sulfide minerals for flotation to obtain a rough concentrate of molybdenum and bismuth. The natural floatability of molybdenum is then utilized to separate molybdenum and bismuth. The sulfide tailings are then sent to tungsten flotation to obtain a rough concentrate of tungsten.

[0042] The specific method is: sulfide ore flotation

[0043] Sulfide ore uses soda ash as a pH adjuster, SN-9 as a collector, BK205 as a frother, and mixed flotation tailings as tungsten flotation feed; the output tungsten rough concentrate has a grade of 3.9% and a recovery rate of 81%;

[0044] Tungsten flotation: Mixed flotation tailings are used for the flotation of scheelite and black tungsten. The collectors for the flotation of black scheelite and black scheelite are fatty acids and their soaps, such as oleic acid, sodium oleate, and oxidized paraffin soap. This experiment first explored the flotation of scheelite using the GY method. The flotation adopts a one-coarse-one-fine-one-sweep method, with soda ash as the pH adjuster, water glass aluminum sulfate mixture as the inhibitor, and GY as the collector. The dosage of the reagents is supplemented according to the on-site conditions. The output tungsten rough concentrate has a grade of 3.9% and a recovery rate of 81%.

[0045] Preferably, in the tungsten flotation, modified hydroxyapatite composite carbon nanotube agent is added as an auxiliary agent, wherein the amount of the auxiliary agent added is 5% of the collector.

[0046] The preparation method of the modified hydroxyapatite composite carbon nanotube agent of this embodiment is as follows:

[0047] S01: Add carbon nanotubes to 2 times the sodium alginate solution, then add hydrochloric acid (5% of the total amount of carbon nanotubes), and then add chitosan solution and stir evenly;

[0048] S02: Add hydroxyapatite to 4 times the volume of sodium dodecyl sulfate solution and stir evenly. Finally, add 5% of the total amount of hydroxyapatite silane coupling agent KH560 and 1% of lanthanum sulfate, stir thoroughly, then wash with water and dry to obtain pre-modified hydroxyapatite.

[0049] S03: Add the hydroxyapatite pre-modified by S02 to 3 times the amount of the S01 product, stir and mix evenly, and finally wash with water and dry to obtain a modified hydroxyapatite composite carbon nanotube agent.

[0050] The mass fraction of the chitosan solution in this embodiment is 20%.

[0051] The amount of chitosan solution added in this embodiment is 5% of the total amount of carbon nanotubes.

[0052] The mass fraction of the sodium alginate solution in this embodiment is 10%.

[0053] The mass fraction of the sodium lauryl sulfate solution in this embodiment is 5%.

[0054] Example 2:

[0055] A method for comprehensive recovery of low-grade tungsten, molybdenum and bismuth as a low-resource resource in this embodiment includes the following steps:

[0056] Before the ore enters the sorting process, it is ground to a fineness that allows the basic monomers of various target minerals to dissociate, and then mixed with sulfide minerals for flotation to obtain a rough concentrate of molybdenum and bismuth. The natural floatability of molybdenum is then utilized to separate molybdenum and bismuth. The sulfide tailings are then sent to tungsten flotation to obtain a rough concentrate of tungsten.

[0057] The specific method is: sulfide ore flotation

[0058] Sulfide ore uses soda ash as a pH adjuster, SN-9 as a collector, BK205 as a frother, and mixed flotation tailings as tungsten flotation feed; the output tungsten rough concentrate has a grade of 3.9% and a recovery rate of 81%;

[0059] Tungsten flotation: Mixed flotation tailings are used for the flotation of scheelite and black tungsten. The collectors for the flotation of black scheelite and black scheelite are fatty acids and their soaps, such as oleic acid, sodium oleate, and oxidized paraffin soap. This experiment first explored the flotation of scheelite using the GY method. The flotation adopts a one-coarse-one-fine-one-sweep method, with soda ash as the pH adjuster, water glass aluminum sulfate mixture as the inhibitor, and GY as the collector. The dosage of the reagents is supplemented according to the on-site conditions. The output tungsten rough concentrate has a grade of 3.9% and a recovery rate of 81%.

[0060] Preferably, in the tungsten flotation, modified hydroxyapatite composite carbon nanotube agent is added as an auxiliary agent, wherein the amount of the auxiliary agent added is 10% of the collector.

[0061] The preparation method of the modified hydroxyapatite composite carbon nanotube agent of this embodiment is as follows:

[0062] S01: Add carbon nanotubes to 3 times the sodium alginate solution, then add hydrochloric acid (10% of the total amount of carbon nanotubes), and then add chitosan solution and stir evenly;

[0063] S02: Add hydroxyapatite to 5 times sodium dodecyl sulfate solution, stir evenly, and finally add 10% of the total amount of hydroxyapatite silane coupling agent KH560 and 5% of lanthanum sulfate, stir thoroughly, then wash with water and dry to obtain pre-modified hydroxyapatite;

[0064] S03: Add the hydroxyapatite pre-modified by S02 to 5 times the amount of the S01 product, stir and mix evenly, and finally wash with water and dry to obtain a modified hydroxyapatite composite carbon nanotube agent.

[0065] The mass fraction of the chitosan solution in this embodiment is 25%.

[0066] The amount of chitosan solution added in this embodiment is 10% of the total amount of carbon nanotubes.

[0067] The mass fraction of the sodium alginate solution in this embodiment is 20%.

[0068] The mass fraction of the sodium lauryl sulfate solution in this embodiment is 10%.

[0069] Example 3:

[0070] A method for comprehensive recovery of low-grade tungsten, molybdenum and bismuth as a low-resource resource in this embodiment includes the following steps:

[0071] Before the ore enters the sorting process, it is ground to a fineness that allows the basic monomers of various target minerals to dissociate, and then mixed with sulfide minerals for flotation to obtain a rough concentrate of molybdenum and bismuth. The natural floatability of molybdenum is then utilized to separate molybdenum and bismuth. The sulfide tailings are then sent to tungsten flotation to obtain a rough concentrate of tungsten.

[0072] The specific method is: sulfide ore flotation

[0073] Sulfide ore uses soda ash as a pH adjuster, SN-9 as a collector, BK205 as a frother, and mixed flotation tailings as tungsten flotation feed; the output tungsten rough concentrate has a grade of 3.9% and a recovery rate of 81%;

[0074] Tungsten flotation: Mixed flotation tailings are used for the flotation of scheelite and black tungsten. The collectors for the flotation of black scheelite and black scheelite are fatty acids and their soaps, such as oleic acid, sodium oleate, and oxidized paraffin soap. This experiment first explored the flotation of scheelite using the GY method. The flotation adopts a one-coarse-one-fine-one-sweep method, with soda ash as the pH adjuster, water glass aluminum sulfate mixture as the inhibitor, and GY as the collector. The dosage of the reagents is supplemented according to the on-site conditions. The output tungsten rough concentrate has a grade of 3.9% and a recovery rate of 81%.

[0075] Preferably, in the tungsten flotation, modified hydroxyapatite composite carbon nanotube agent is added as an auxiliary agent, wherein the amount of the auxiliary agent added is 7.5% of the collector.

[0076] The preparation method of the modified hydroxyapatite composite carbon nanotube agent of this embodiment is as follows:

[0077] S01: Add carbon nanotubes to 2.5 times the sodium alginate solution, then add hydrochloric acid (7.5% of the total amount of carbon nanotubes), and then add chitosan solution and stir evenly;

[0078] S02: Add hydroxyapatite to 4.5 times of sodium dodecyl sulfate solution, stir evenly, and finally add 7.5% of silane coupling agent KH560 and 3% of lanthanum sulfate to the total amount of hydroxyapatite, stir thoroughly, then wash with water and dry to obtain pre-modified hydroxyapatite;

[0079] S03: Add the hydroxyapatite pre-modified by S02 to 4 times the amount of the S01 product, stir and mix evenly, and finally wash with water and dry to obtain a modified hydroxyapatite composite carbon nanotube agent.

[0080] The mass fraction of the chitosan solution in this embodiment is 22.5%.

[0081] The amount of chitosan solution added in this embodiment is 7.5% of the total amount of carbon nanotubes.

[0082] The mass fraction of the sodium alginate solution in this embodiment is 15%.

[0083] The mass fraction of the sodium lauryl sulfate solution in this embodiment is 7.5%.

[0084] On July 24, 2010, the tungsten, molybdenum, and bismuth polymetallic ore mine underwent industrial commissioning, employing a molybdenum-bismuth isoflurane-flotation-GY process for tungsten separation. Molybdenum and bismuth achieved excellent beneficiation performance, with a molybdenum concentrate grade of 42.36% and a recovery rate of 82.49%, and a bismuth concentrate grade of 27.10% and a recovery rate of 69.84%. However, tungsten performance remained suboptimal. Tungsten rougher tailings were high, generally around 0.15, while the rougher concentrate grade was low, generally between 2-3%. Fluorite and calcium-containing gangue minerals tended to float, leading to unstable operation and high sludging in the rougher. Increasing the inhibitor dosage to suppress impurity minerals not only resulted in poor suppression but also increased tungsten suppression, resulting in higher tailings, exceeding 0.2. Heating the scheelite for separation, however, was not ideal due to the high concentration of fluorite and calcium-containing gangue minerals, resulting in only 30%-45% scheelite concentrate. Through the analysis of the results of small-scale tests, it was found that most of the ore body was scheelite, and the caustic soda method was more suitable for tungsten selection. Under high alkalinity conditions, the collector was 733, which had an inhibitory effect on fluorite minerals and was more selective for scheelite.

[0085] On July 2, 2010, the tungsten selection process using caustic soda was implemented. As the company's supply department did not have 733 reagents in stock, OS-2 was temporarily used instead of the tungsten collector. The flotation phenomenon changed significantly, and the tungsten roughing foam changed from the original fine, empty, and brittle dark gray to a viscous white foam (the color of calcite foam). The tungsten flotation effect was significantly improved, with the grade of the coarse concentrate reaching more than 5% and the tailings between 0.09-0.07, but the foam was viscous. On July 4, the tungsten collector was changed to GYR, and the tungsten roughing foam changed from a viscous white foam to a large, solid white foam. The flotation effect was even better than that using OS-2 as the collector, with the grade of the coarse concentrate reaching more than 7% and the tailings basically stable between 0.02-0.05.

[0086] On July 9, the tungsten collector was switched to 733. The effectiveness of 733 on tungsten collection was tested. The results showed that the color of the tungsten roughing foam was the same as that of GYR, but the foam produced by 733 was larger than that of GYR. The flotation index was similar to that of GYR, and satisfactory flotation results were also achieved. 733 was used until the industrial trial ended on July 16. The process indicators of the GY method and the caustic soda method are compared in the following table:

[0087] Production debugging process comparison indicators

[0088]

[0089] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations that come within the meaning and range of equivalents of the claims be embraced therein.

[0090] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A method for comprehensive recovery of low-grade tungsten, molybdenum and bismuth resources, characterized in that: The following steps are involved: Before the ore enters the sorting process, it is ground to a fineness that allows the basic monomers of various target minerals to dissociate, and then mixed with sulfide minerals for flotation to obtain a rough molybdenum and bismuth concentrate. The natural floatability of molybdenum is then utilized to separate molybdenum and bismuth, and the sulfide tailings are fed into tungsten flotation to obtain a rough tungsten concentrate. The specific method is: Sulfide ore uses soda ash as pH adjuster, 733 reagent as collector, BK205 as frother, water glass aluminum sulfate mixture as inhibitor, and mixed flotation tailings as tungsten flotation feed; Tungsten flotation: Mixed flotation tailings for flotation of scheelite and black tungsten, fatty acids and their soaps as collectors for flotation of black scheelite and black scheelite; In the tungsten flotation, modified hydroxyapatite composite carbon nanotube agent is added as an auxiliary agent, wherein the amount of the auxiliary agent added is 5-10% of the collector.

2. The method for comprehensive recovery of low-grade tungsten, molybdenum and bismuth as claimed in claim 1, characterized in that: The preparation method of the modified hydroxyapatite composite carbon nanotube agent is as follows: S01: Add carbon nanotubes to 2-3 times the volume of sodium alginate solution, then add hydrochloric acid (5-10% of the total volume of carbon nanotubes), and then add chitosan solution and stir evenly; S02: Add hydroxyapatite to 4-5 times of sodium dodecyl sulfate solution, stir evenly, and finally add 5-10% of the total amount of hydroxyapatite silane coupling agent KH560 and 1-5% of lanthanum sulfate, stir thoroughly, then wash with water and dry to obtain pre-modified hydroxyapatite; S03: Add the hydroxyapatite pre-modified by S02 to 3-5 times the amount of the S01 product, stir and mix evenly, and finally wash with water and dry to obtain a modified hydroxyapatite composite carbon nanotube agent.

3. The method for comprehensive recovery of low-grade tungsten, molybdenum and bismuth as claimed in claim 2, characterized in that: The mass fraction of the chitosan solution is 20-25%.

4. The method for comprehensive recovery of low-grade tungsten, molybdenum and bismuth as claimed in claim 3, characterized in that: The amount of chitosan solution added is 5-10% of the total amount of carbon nanotubes.

5. The method for comprehensive recovery of low-grade tungsten, molybdenum and bismuth as claimed in claim 3, characterized in that: The mass fraction of the sodium alginate solution is 10-20%.

6. The method for comprehensive recovery of low-grade tungsten, molybdenum and bismuth as claimed in claim 5, characterized in that: The mass fraction of the sodium alginate solution is 15%.

7. The method for comprehensive recovery of low-grade tungsten, molybdenum and bismuth as claimed in claim 2, characterized in that: The mass fraction of the sodium lauryl sulfate solution is 5-10%.

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