ORE DRESSING PROCESS FOR MEDIUM-GRADE AND LOW-GRADE MIXED COLLOPHANITE

Abstract

An ore dressing process for medium-grade and low-grade mixed collophanite includes the following steps: S1; crushing ores to obtain crushed ores; S2: screening the crushed ores to obtain fine-fraction ores and coarse-fraction ores divided into at least two size fractions; S3: performing a photoelectric separation to the coarse-fraction ores of different size fractions to obtain photoelectric separation concentrates and photoelectric separation tailings of each size fraction; S4: combining the photoelectric separation concentrates of the each size fraction to obtain pre-enriched concentrates; S5: combining the fine-fraction ores and the pre-enriched concentrates, and then performing an ore grinding to obtain minerals to be separated; S6: adding water to the minerals to be separated to obtain a floatation pulp, and then performing a floatation to obtain phosphate concentrates and tailings.

Claims

1. An ore dressing process for a medium-grade and low-grade mixed collophanite, comprising the following steps: S1: crushing green ores to obtain crushed ores; S2: screening the crushed ores to obtain fine-fraction ores and coarse-fraction ores divided into at least two size fractions; S3: respectively performing a photoelectric separation to the coarse-fraction ores of different size fractions to obtain photoelectric separation concentrates and photoelectric separation tailings of each size fraction; S4: combining the photoelectric separation concentrates of the each size fraction to obtain pre-enriched concentrates; S5: combining the fine-fraction ores and the pre-enriched concentrates, and then performing an ore grinding to obtain minerals to be separated; S6: adding water to the minerals to be separated to obtain a floatation pulp, and then performing a floatation to obtain phosphate concentrates and tailings.

2. The ore dressing process according to claim 1, wherein in step S1, a particle size of the crushed ores is less than or equal to 60 mm.

3. The ore dressing process according to claim 1, wherein in step S2, a particle size of the fine-fraction ores is less than or equal to 8 mm.

4. The ore dressing process according to claim 1, wherein in step S2, a particle size of the coarse-fraction ores is more than 8 mm.

5. The ore dressing process according to claim 1, wherein in step S3, the ore dressing process further comprises a step of respectively and repetitively performing the photoelectric separation by using the photoelectric separation tailings of the each size fraction as raw materials.

6. The ore dressing process according to claim 5, wherein in step S3, a grade of P.sub.2O.sub.5 in the photoelectric separation tailings at a last time is less than or equal to 10%.

7. The ore dressing process according to claim 1, wherein in step S5, a weight percentage of the minerals to be separated with a particle size less than or equal 0.074 mm in an ore pulp to be separated is 75%-90%.

8. The ore dressing process according to claim 1, wherein in step S6, the floatation comprises at least one time of roughing, at least one time of concentration and at least one time of scavenging.

9. The ore dressing process according to claim 8, wherein in step S6, the floatation comprises one time of roughing, one time of concentration and one time of scavenging, and further comprises the following steps: A1: adding an inhibitor and a collector into the floatation pulp, and performing stirring and aeration to obtain roughing concentrates and roughing tailings; A2: adding the inhibitor and the collector into the roughing concentrates, and performing stirring and aeration to obtain final phosphate concentrates and concentration middlings; A3: adding the inhibitor and the collector into the roughing tailings, and performing stirring and aeration to obtain scavenging concentrates and final tailings.

10. The ore dressing process according to claim 9, wherein the inhibitor is a mixed acid.

11. The ore dressing process according to claim 10, wherein the inhibitor comprises 4-6 parts of sodium tripolyphosphate, 2-3 parts of hexametaphosphate and 2-3 parts of phosphoric acid by weight.

12. The ore dressing process according to claim 9, wherein the collector comprises 4-5 parts of sodium vegetable oleate and 1 part of dodecyl phosphate by weight.

13. The ore dressing process according to claim 12, wherein the sodium vegetable oleate is prepared from a NaOH solution and a vegetable oil.

14. The ore dressing process according to claim 13, wherein a method for preparing the collector comprises adding the NaOH solution into a mixed solution of the vegetable oil and the dodecyl phosphate, and performing heating for a reaction to obtain the collector.

15. The ore dressing process according to claim 14, wherein the vegetable oil comprises at least one selected from the group consisting of cottonseed oil, rice bran oil, castor oil, corn oil and soybean oil.

16. The ore dressing process according to claim 14, wherein a weight ratio the NaOH solution to the mixed solution is 0.1-0.2:1.

17. The ore dressing process according to claim 14, wherein a reaction temperature of the heating for the reaction is 60-80° C. and a reaction time is 3-5 hours.

18. The ore dressing process according to claim 9, wherein in step A1, an amount of the inhibitor added is 2000-3000 g/t green ore and/or an amount of the collector added is 400-800 g/t green ore.

19. The ore dressing process according to claim 9, wherein in step A2, an amount of the inhibitor added is 400-600 g/t green ore and/or an amount of the collector added is 40-80 g/t green ore.

20. The ore dressing process according to claim 9, wherein in step A3, an amount of the inhibitor added is 800-1200 g/t green ore and/or an amount of the collector added is 150-250 g/t green ore.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0053] FIGURE illustrates a flowchart of ore dressing process for medium-grade and low-grade mixed collophanite provided by the present application.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0054] The technical solution of the present application will be further described below in detail with reference to the drawings, but the scope of protection of the present application is not limited thereto.

Example 1

[0055] Medium-grade and low-grade mixed collophanite was obtained from a certain ore dressing plant in Mabian region, the grade of P.sub.2O.sub.5 was 22%, and the ore dressing process was as illustrated in the FIGURE, which included the following steps:

[0056] In S1, green ores were crushed to obtain crushed ores with a particle size less than or equal to 60 mm.

[0057] In S2, the crushed ores are screened to obtain fine-fraction ores with a particle size less than or equal to 8 mm and coarse-fraction ores of two different size fractions of +8-30 mm and +30-60 mm.

[0058] In S3, photoelectric separation was respectively performed to the coarse-fraction ores of the different size fractions, samples were enabled to enter a separator at speed of 3 m/s, the samples were illuminated by using electromagnetic waves with a wavelength of 0.05 nm and separation was performed to obtain photoelectric separation concentrates and photoelectric separation tailings of each size fraction.

[0059] In S4, the photoelectric separation tailings of each size fraction were respectively returned to step S3, and the operation was repeated for 2-3 times until the grade of P.sub.2O.sub.5 in the photoelectric separation tailings was less than or equal to 10%, wherein photoelectric separation concentrates and photoelectric separation tailings were obtained at each time of photoelectric separation of each size fraction.

[0060] In S5, the obtained photoelectric separation concentrates were all combined to obtain pre-enriched concentrates; the obtained photoelectric separation tailings of different size fractions were combined to obtain tailings I.

[0061] In S6, the fine-fraction ores and the pre-enriched concentrates were combined, and then ore grinding was performed to obtain ore pulp to be separated, wherein the weight of minerals with a particle size less than or equal to 0.074 mm accounted for 75% of the total weight.

[0062] In S7, water was added to the ore pulp to be separated to obtain floatation pulp with mass percent concentration of 30%, and then floatation including one time of roughing, one time of concentration and one time of scavenging was performed to obtain final phosphate concentrates, wherein the specific operation included the following steps:

[0063] In A1, 2000 g/t green ore of an inhibitor and 400 g/t green ore of a collector were added into the floatation pulp, and stirring and aeration were performed to obtain roughing concentrates and roughing tailings.

[0064] In A2, 400 g/t green ore of an inhibitor and 40 g/t green ore of a collector were added into the roughing concentrates, and stirring and aeration were performed to obtain the final phosphate concentrates and concentration middlings.

[0065] In A3, 800 g/t green ore of an inhibitor and 150 g/t green ore of a collector were added into the roughing tailings, and stirring and aeration were performed to obtain scavenging concentrates and final tailings.

[0066] Herein, the concentration middlings and the scavenging concentrates were respectively returned to step A1, and steps A1-A3 were repeated.

[0067] The inhibitor included 4 parts of sodium tripolyphosphate, 2 parts of hexametaphosphate and 2 parts of phosphoric acid by weight. The collector included 4 parts of sodium vegetable oleate and 1 part of dodecyl phosphate by weight.

[0068] A method for preparing the collector included adding NaOH solution into mixed solution of vegetable oil and dodecyl phosphate, wherein the mass percent concentration of NaOH was 20%, and performing heating for reaction for 5 h at 60° C. to obtain.

[0069] Herein, the vegetable oil included cottonseed oil, rice bran oil, castor oil, corn oil and soybean oil. The weight ratio the NaOH solution to the mixed solution is 0.2:1.

Example 2

[0070] Medium-grade and low-grade mixed collophanite was obtained from a certain ore dressing plant in Leibo, the grade of P.sub.2O.sub.5 was 20%, and the ore dressing process was as illustrated in the FIGURE, which included the following steps:

[0071] In S1, green ores were crushed to obtain crushed ores with a particle size less than or equal to 60 mm.

[0072] In S2, the crushed ores are screened to obtain fine-fraction ores with a particle size less than or equal to 8 mm and coarse-fraction ores of two different size fractions of +8-30 mm and +30-60 mm.

[0073] In S3, photoelectric separation was respectively performed to the coarse-fraction ores of the different size fractions, samples were enabled to enter a separator at speed of 3 m/s, the samples were illuminated by using electromagnetic waves with a wavelength of 0.05 nm and separation was performed to obtain photoelectric separation concentrates and photoelectric separation tailings of each size fraction.

[0074] In S4, the photoelectric separation tailings of each size fraction were respectively returned to step S3, and the operation was repeated for 2-3 times until the grade of P.sub.2O.sub.5 in the photoelectric separation tailings was less than or equal to 10%, wherein photoelectric separation concentrates and photoelectric separation tailings were obtained at each time of photoelectric separation of each size fraction.

[0075] In S5, the obtained photoelectric separation concentrates were all combined to obtain pre-enriched concentrates; the obtained photoelectric separation tailings of different size fractions were combined to obtain tailings I.

[0076] In S6, the fine-fraction ores and the pre-enriched concentrates were combined, and then ore grinding was performed to obtain ore pulp to be separated, wherein the weight of minerals with a particle size less than or equal to 0.074 mm accounted for 85% of the total weight.

[0077] In S7, water was added to the ore pulp to be separated to obtain floatation pulp with mass percent concentration of 30%, and then floatation including one time of roughing, one time of concentration and one time of scavenging was performed to obtain final phosphate concentrates, wherein the specific operation included the following steps:

[0078] In A1, 2500 g/t green ore of an inhibitor and 600 g/t green ore of a collector were added into the floatation pulp, and stirring and aeration were performed to obtain roughing concentrates and roughing tailings.

[0079] In A2, 500 g/t green ore of an inhibitor and 60 g/t green ore of a collector were added into the roughing concentrates, and stirring and aeration were performed to obtain the final phosphate concentrates and concentration middlings.

[0080] In A3, 1000 g/t green ore of an inhibitor and 200 g/t green ore of a collector were added into the roughing tailings, and stirring and aeration were performed to obtain scavenging concentrates and final tailings.

[0081] Herein, the concentration middlings and the scavenging concentrates were respectively returned to step A1, and steps A1-A3 were repeated.

[0082] The inhibitor included 5.5 parts of sodium tripolyphosphate, 2.5 parts of hexametaphosphate and 2.5 parts of phosphoric acid by weight. The collector included 4.5 parts of sodium vegetable oleate and 1 part of dodecyl phosphate by weight.

[0083] A method for preparing the collector included adding NaOH solution into mixed solution of vegetable oil and dodecyl phosphate, wherein the mass percent concentration of NaOH was 20%, and performing heating for reaction for 4 h at 70° C. to obtain.

[0084] Herein, the vegetable oil included cottonseed oil, rice bran oil, castor oil, corn oil and soybean oil. The weight ratio the NaOH solution to the mixed solution is 0.2:1.

Example 3

[0085] Medium-grade and low-grade mixed collophanite was obtained from a certain ore dressing plant in Jinyang, the grade of P.sub.2O.sub.5 was 18%, and the ore dressing process was as illustrated in the FIGURE, which included the following steps:

[0086] In S1, green ores were crushed to obtain crushed ores with a particle size less than or equal to 60 mm.

[0087] In S2, the crushed ores are screened to obtain fine-fraction ores with a particle size less than or equal to 8 mm and coarse-fraction ores of two different size fractions of +8-30 mm and +30-60 mm.

[0088] In S3, photoelectric separation was respectively performed to the coarse-fraction ores of the different size fractions, samples were enabled to enter a separator at speed of 3 m/s, the samples were illuminated by using electromagnetic waves with a wavelength of 0.05 nm and separation was performed to obtain photoelectric separation concentrates and photoelectric separation tailings of each size fraction.

[0089] In S4, the photoelectric separation tailings of each size fraction were respectively returned to step S3, and the operation was repeated for 2-3 times until the grade of P.sub.2O.sub.5 in the photoelectric separation tailings was less than or equal to 10%, wherein photoelectric separation concentrates and photoelectric separation tailings were obtained at each time of photoelectric separation of each size fraction.

[0090] In S5, the obtained photoelectric separation concentrates were all combined to obtain pre-enriched concentrates; the obtained photoelectric separation tailings of different size fractions were combined to obtain tailings I.

[0091] In S6, the fine-fraction ores and the pre-enriched concentrates were combined, and then ore grinding was performed to obtain ore pulp to be separated, wherein the weight of minerals with a particle size less than or equal to 0.074 mm accounted for 90% of the total weight.

[0092] In S7, water was added to the ore pulp to be separated to obtain floatation pulp with mass percent concentration of 30%, and then floatation including one time of roughing, one time of concentration and one time of scavenging was performed to obtain final phosphate concentrates, wherein the specific operation included the following steps:

[0093] In A1, 3000 g/t green ore of an inhibitor and 800 g/t green ore of a collector were added into the floatation pulp, and stirring and aeration were performed to obtain roughing concentrates and roughing tailings.

[0094] In A2, 600 g/t green ore of an inhibitor and 80 g/t green ore of a collector were added into the roughing concentrates, and stirring and aeration were performed to obtain the final phosphate concentrates and concentration middlings.

[0095] In A3, 1200 g/t green ore of an inhibitor and 250 g/t green ore of a collector were added into the roughing tailings, and stirring and aeration were performed to obtain scavenging concentrates and final tailings.

[0096] Herein, the concentration middlings and the scavenging concentrates were respectively returned to step A1, and steps A1-A3 were repeated.

[0097] The inhibitor included 6 parts of sodium tripolyphosphate, 3 parts of hexametaphosphate and 3 parts of phosphoric acid by weight. The collector included 5 parts of sodium vegetable oleate and 1 part of dodecyl phosphate by weight.

[0098] A method for preparing the collector included adding NaOH solution into mixed solution of vegetable oil and dodecyl phosphate, wherein the mass percent concentration of NaOH was 20%, and performing heating for reaction for 3 h at 80° C. to obtain.

[0099] Herein, the vegetable oil included cottonseed oil, rice bran oil and castor oil. The weight ratio the NaOH solution to the mixed solution is 0.2:1.

Comparative Example 1

[0100] The indexes of separating medium-grade and low-grade mixed collophanite in example 1 of the present application were compared with that in comparative example 1, the medium-grade and low-grade mixed collophanite in example 1 was used in comparative example 1, and the ore dressing process was the technical solution recorded in example 1 in Chinese patent literature CN201510991054.3 (this comparative example was compared with the prior art and was used to prove that the ore dressing process of the present application had a better effect).

Comparative Example 2

[0101] The indexes of separating medium-grade and low-grade mixed collophanite in example 1 of the present application were compared with that in comparative example 2, the medium-grade and low-grade mixed collophanite in example 1 was used in comparative example 2, the ore dressing process had a difference lying in directly performing ore grinding to the green ores to obtain ore pump to be separated without performing steps S1-S5 in example 1, and other conditions were the same as that in example 1 of the present application except the amount of used chemicals, ore grinding fineness and subsequent process flow (this comparative example was compared with the technical solution without photoelectric separation steps and was used to prove that the ore dressing process of the present application had a better effect).

Comparative Example 3

[0102] The indexes of separating medium-grade and low-grade mixed collophanite in example 1 of the present application were compared with that in comparative example 3, the medium-grade and low-grade mixed collophanite in example 1 was used in comparative example 3, the ore dressing process had a difference lying in replacing the collector with fatty acid salt mainly including sodium oleate in the prior art and replacing the inhibitor with sulfuric acid and phosphoric acid at a mass ratio of 5:1 in the prior art, and other conditions were the same as that in example 1 of the present application except the amount of used chemicals, ore grinding fineness and adopted process flow (this comparative example was compared with the technical solution in which the collector and the inhibitor were replaced with the chemicals in the prior art at the same time, and was used to prove that the ore dressing process of the present application had a better effect).

Comparative Example 4

[0103] The indexes of separating medium-grade and low-grade mixed collophanite in example 1 of the present application were compared with that in comparative example 4, the medium-grade and low-grade mixed collophanite in example 1 was used in comparative example 4, the ore dressing process had a difference lying in replacing the collector with fatty acid salt mainly including sodium oleate in the prior art, and other conditions were the same as that in example 1 of the present application except the selection of inhibitor, the amount of used chemicals, ore grinding fineness and adopted process flow (this comparative example was compared with the technical solution in which the collector was replaced with the chemical in the prior art, and was used to prove that the ore dressing process of the present application had a better effect).

Comparative Example 5

[0104] The indexes of separating medium-grade and low-grade mixed collophanite in example 1 of the present application were compared with that in comparative example 5, the medium-grade and low-grade mixed collophanite in example 1 was used in comparative example 5, the ore dressing process had a difference lying in replacing the inhibitor with sulfuric acid and phosphoric acid at a mass ratio of 5:1 in the prior art, and other conditions were the same as that in example 1 of the present application except the selection of collector, amount of used chemicals, ore grinding fineness and adopted process flow (this comparative example was compared with the technical solution in which the inhibitor was separately replaced with the chemical in the prior art, and was used to prove that the ore dressing process of the present application had a better effect).

Comparative Example 6

[0105] The indexes of separating medium-grade and low-grade mixed collophanite in example 1 of the present application were compared with that in comparative example 6, the medium-grade and low-grade mixed collophanite in example 1 was used in comparative example 6, the ore dressing process had a difference lying in removing magnesium through reverse floatation by using the chemical system in the examples and then removing silicon through direct floatation by using sodium carbonate and dodecamine, the reverse floatation chemical system, ore grinding fineness and industrial flow were the same as that in example 1 of the present application, the direct floatation used the concentrate product obtained after magnesium removal as raw materials, the pH value was regulated to about 9, and 1000 g/t of sodium carbonate and 500 g/t of dodecamine were added as the collector.

Comparative Example 7

[0106] The indexes of separating medium-grade and low-grade mixed collophanite in example 1 of the present application were compared with that in comparative example 7, a different of comparative example 7 form example 1 lay in that no sodium tripolyphosphate and hexametaphosphate were added into the inhibitor, and other conditions were the same as that in example 1 of the present application except the amount of used chemicals, ore grinding fineness and adopted process flow.

Comparative Example 8

[0107] The indexes of separating medium-grade and low-grade mixed collophanite in example 1 of the present application were compared with that in comparative example 8, a different of comparative example 8 form example 1 lay in that no sodium tripolyphosphate was added into the inhibitor, and other conditions were the same as that in example 1 of the present application except the amount of used chemicals, ore grinding fineness and adopted process flow.

Comparative Example 9

[0108] The indexes of separating medium-grade and low-grade mixed collophanite in example 1 of the present application were compared with that in comparative example 9, a different of comparative example 9 form example 1 lay in that no hexametaphosphate was added into the inhibitor, and other conditions were the same as that in example 1 of the present application except the amount of used chemicals, ore grinding fineness and adopted process flow.

[0109] The comparison of the experimental results of examples 1-3 and comparative examples 1-9 was shown in the following table (there was a slight difference in the grade of green ores between comparative examples 1-9 and example 1, because there was a human error in the experimental operation, which was a normal phenomenon):

TABLE-US-00001 Group Product Yield % Grade % Recovery rate % Example 1 Final phosphate 49.93 32.84 77.03 concentrate Tailing 50.07 9.76 22.96 Green ore 100.00 21.29 100.00 Comparative Final phosphate 42.29 30.54 59.94 example 1 concentrate Tailing 57.71 14.96 40.06 Green ore 100.00 21.55 100.00 Comparative Final phosphate 48.47 27.84 63.64 example 2 concentrate Tailing 51.53 14.96 36.36 Green ore 100.00 21.20 100.00 Comparative Final phosphate 50.41 28.84 67.74 example 3 concentrate Tailing 49.59 13.96 32.26 Green ore 100.00 21.46 100.00 Comparative Final phosphate 46.92 30.54 67.57 example 4 concentrate Tailing 53.08 12.96 32.43 Green ore 100.00 21.21 100.00 Comparative Final phosphate 52.62 28.54 70.98 example 5 concentrate Tailing 47.38 12.96 29.02 Green ore 100.00 21.16 100.00 Comparative Final phosphate 41.18 33.08 63.69 example 6 concentrate Tailing 58.82 13.20 36.31 Green ore 100.00 21.39 100.00 Comparative Final phosphate 47.47 31.71 70.91 example 7 concentrate Tailing 52.53 11.76 29.09 Green ore 100.00 21.23 100.00 Comparative Final phosphate 46.94 32.71 71.10 example 8 concentrate Tailing 53.06 11.76 28.90 Green ore 100.00 21.59 100.00 Comparative Final phosphate 47.57 30.71 68.59 example 9 concentrate Tailing 52.43 12.76 31.41 Green ore 100.00 21.30 100.00 Example 2 Final phosphate 43.80 32.64 72.20 concentrate Tailing 56.20 9.80 27.80 Green ore 100.00 19.80 100.00 Example 3 Final phosphate 37.26 30.84 67.36 concentrate Tailing 62.74 8.87 32.64 Green ore 100.00 17.06 100.00

[0110] As can be seen from the above table, compared with example 1, the yield, grade and recovery rate of the final phosphate concentrates obtained in comparative example 1 decrease significantly, and the yield, grade and recovery rate of the obtained tailings increase significantly; for comparative examples 2 and 4, the yield of the obtained final phosphate concentrates decreases slightly, the grade and recovery rate of the obtained final phosphate concentrates decrease significantly, the yield of the obtained tailings increases slightly, and the grade and recovery rate of the obtained tailings increase significantly; for comparative examples 3 and 5, the yield of the obtained final phosphate concentrates increases, the grade and recovery rate of the obtained final phosphate concentrates decrease significantly, the yield of the obtained tailings decreases, and the grade and recovery rate of the obtained tailings increase significantly. Accordingly, it can be seen that the process in example 1 of the present can more fully separate the phosphate concentrates in the green ores than the process in comparative examples 1-5; at the same time, although the yield in comparative examples 3 and 5 increases, their grade decreases significantly, which indicates that other impurities float up together, proving that the collector performance in comparative examples 3 and 5 is poorer than that in example 1.

[0111] Compared with example 1, the yield, grade and recovery rate of the obtained final phosphate concentrates in comparative examples 7-9 decrease significantly, which indicates that the effect of the combined use of phosphoric acid, sodium tripolyphosphate and hexametaphosphate in the present application is significantly improved compared with the single use or separate use of each component, that is, there is a synergistic effect among the components of the inhibitor in the present application.

[0112] Therefore, the ore dressing process for medium-grade and low-grade mixed collophanite provided by the present application achieves the effects of high ore dressing efficiency, small amount of ores for floatation, low energy consumption, low floatation chemical cost and environmental friendliness.

[0113] What are described above are just preferred examples of the present application. It should be understood that the present application is not limited to the examples disclosed herein, and should not be regarded as excluding other examples, but may be used for various other combinations, modifications and environments, and may be modified through the above-mentioned teaching or technology or knowledge in the related art within the scope of the concept described herein. However, any modifications and changes made by those skilled in the art without departing from the spirit and scope of the present application shall fall within the scope of protection defined by the attached claims of the present application.