A method for flotation recovery of a pyrochlore ore containing carbonate and mica

Abstract

The present invention provides a method for flotation recovery of pyrochlore ore containing carbonate and mica, comprising the following steps: the original pyrochlore ore is crushed, ground, and subjected to primary magnetic separation to obtain magnetic products and non-magnetic products; the non-magnetic products are subjected to a classification operation, the coarse-grained minerals are subjected to a gravity separation operation to obtain heavy minerals, and the fine-grained minerals are de-sludged to obtain underflow products; the heavy minerals and the underflow products are combined and subjected to one-stage flotation, one-stage roughing, and two-stage scavenging to obtain in-cell product 3; in-cell product 3 is subjected to a thickening operation, then two-stage roughing and one-stage scavenging are carried out to obtain foam product 5; foam product 5 is subjected to 3-4 times of cleaning to obtain foam product 6, and foam product 6 is the pyrochlore concentrate. The present invention simplifies the pyrochlore beneficiation process, shortens the process flows of de-sludging and flotation, and further improves the grade and recovery rate of the pyrochlore concentrate.

Description

Technical Field

[0001] The present invention relates to the technical field of ore dressing, and particularly to a method for ore dressing and recovering pyrochlore ore containing carbonate and mica by flotation as the main means. Background Art

[0002] Pyrochlore is the main source of metallic niobium and an important mineral raw material for extracting rare earth elements, tantalum and radioactive elements. Flotation is mostly used for the ore dressing of pyrochlore. However, when the ore contains a high content of carbonate minerals such as calcite and dolomite, as well as mica, such as the carbonate content is more than 20% and the mica content is more than 10%, it can seriously interfere with the flotation of pyrochlore. Therefore, these two types of minerals need to be removed before the flotation of pyrochlore.

[0003] Due to the low hardness of carbonate minerals, serious slime phenomenon occurs during the ore dressing grinding process, which can seriously interfere with the flotation process of the entire process, such as carbonate flotation, mica flotation and pyrochlore flotation, resulting in unstable production. Therefore, a desliming operation needs to be carried out before flotation to remove the fine slime that interferes with flotation. Generally speaking, taking into account other non-target minerals, the ore dressing process of this type of pyrochlore can be basically summarized as grinding - multi-stage desliming - flotation to remove carbonate - flotation to remove mica - dehydration - magnetic separation - pyrochlore flotation.

[0004] However, since pyrochlore is also prone to slime, in normal production, in order to avoid the loss of pyrochlore as much as possible, generally 5 - 8 stages of desliming operations are carried out. Even so, there are still problems with low efficiency in the multi-stage desliming operation, resulting in large losses of useful elements in the deslimed minerals. Secondly, the operation sections of flotation to remove carbonate and flotation to remove mica are both composed of 4 - 5 stages of flotation operations. The complex flotation process of removing gangue by removing impurities increases the difficulty of production management and inevitably causes losses of some useful minerals.

[0005] In the patent literature, a method for recovering barium-strontium pyrochlore from weathered and altered carbonate-type niobium polymetallic ore, application number: 201910721915.4, uses a process of flotation followed by gravity separation for pyrochlore flotation. If this process is used for this type of pyrochlore ore, the following problems exist: 1. Although the flotation process can remove carbonate minerals by using methods such as floating phosphorus, the removal effect on mica minerals is poor; 2. Multi-stage magnetic separation is adopted, and the strong magnetic method can remove some mica minerals but is likely to cause losses of pyrochlore minerals; 3. Pyrochlore minerals are brittle and are prone to slime and refinement during the grinding process. However, the existing gravity separation method is limited by the processing capacity and the particle size of the processed materials, and the gravity separation effect on fine-grained materials (below 30 microns) is poor, which is extremely likely to cause losses of pyrochlore minerals. Therefore, for the recovery of fine-grained pyrochlore minerals, flotation is still the main means and has higher efficiency.

[0006] Patent Document: A method for obtaining pyrochlore concentrate, application number 201710822096.3, which uses shaking table gravity separation to obtain rough concentrate and then hydroxamic acid flotation to obtain pyrochlore. When this process is used for pyrochlore ores with high contents of carbonate and mica, the following problems exist: 1. When using the all-size gravity separation method, there is a problem of mutual interference between coarse and fine minerals, resulting in poor gravity separation effect and inability to effectively recover pyrochlore distributed in particles after fine grinding. Generally, a large amount of pyrochlore is lost here; 2. When using the shaking table gravity separation method for preselection, the removal efficiency of carbonate and mica minerals is not high, and a large amount of carbonate and mica minerals are easily left, thus affecting pyrochlore flotation; 3. In the pyrochlore flotation stage of this method, hydroxamic acid collectors are used, and the selectivity for pyrochlore containing carbonate ore is poor, and it is not easy to obtain high-grade pyrochlore concentrate products. Summary of the Invention

[0007] The present invention provides a flotation recovery method for pyrochlore ore containing carbonate and mica, which simplifies the pyrochlore beneficiation process and improves the beneficiation recovery rate.

[0008] The technical solution of the present invention is realized as follows: A flotation recovery method for pyrochlore ore containing carbonate and mica, comprising the following steps:

[0009] (1) The original pyrochlore ore is crushed and then ground to a particle size of -0.074 mm with a mass ratio of 65%-80% to obtain a ground product. The ground product is subjected to a first magnetic separation to obtain a magnetic product and a non-magnetic product, and the magnetic separation intensity is 0.1-0.2 T; the magnetic product can be discarded as tailings or enter the iron concentration operation as a by-product iron rough concentrate;

[0010] (2) The non-magnetic product is subjected to a first classification operation with a classification particle size of 30-40 microns to obtain fine-grained minerals and coarse-grained minerals. The equipment used for classification is a hydrocyclone, a spiral chute, an inclined plate classifier, etc.; the coarse-grained minerals are subjected to a gravity separation operation to obtain light minerals and heavy minerals. The equipment used for gravity separation is one of a centrifugal concentrator, a spiral chute, a spiral concentrator, a shaking table, etc.; the fine-grained minerals are deslimed with a desliming particle size of 5-20 microns to obtain a coarser underflow product and a finer overflow product. The overflow product and the light minerals are used as tailings 1. The equipment used for desliming is one or several of a hydrocyclone, an inclined plate classifier, a disc centrifuge, etc.;

[0011] (3) The heavy minerals and the underflow product are combined and subjected to a first-stage flotation to obtain a foam product 1 and a cell product 1. The foam product 1 is used as tailings 2; the cell product 1 is subjected to a first-stage roughing to obtain a foam product 2 and a cell product 2. The cell product 2 is subjected to two-stage scavenging to obtain a cell product 3;

[0012] (4) The foam product 2 obtained in step (3) is subjected to a blank beneficiation once to obtain a foam product 4 and a bottom product 4. The foam product 4 is tailings 3, and the bottom product 4 is returned to the first roughing stage.

[0013] (5) The in-tank product 3 obtained in step (3) is subjected to a thickening operation, and then two roughing stages are carried out to obtain a foam product 5 and a bottom product 5. The bottom product 5 is subjected to a scavenging operation once to obtain tailings 4; the foam product 5 is subjected to 3 - 4 beneficiation stages to obtain a foam product 6, and the foam product 6 is pyrochlore concentrate.

[0014] Further, in step (3), the specific method of the first-stage flotation is as follows: adjust the pulp concentration to 35 - 45%, the pH to 8 - 10.5, and then add 500 - 5000 g / t of inhibitor and 200 - 1000 g / t of anionic collector for flotation. The inhibitor is one or more of sodium silicate, starch, and carboxymethyl cellulose, preferably sodium silicate. The anionic collector is one or more of sodium oleate, oxidized paraffin soap, sodium petroleum sulfonate, and alkyl sulfonate, preferably oxidized paraffin soap.

[0015] Further, in step (3), in the first roughing stage and the two scavenging stages, the flotation reagents and their dosages are as follows: 100 - 600 g / t of inhibitor, 100 - 500 g / t of anionic collector, 50 - 300 g / t of cationic collector. As the flotation operation progresses, the dosage of the anionic collector gradually decreases; the inhibitor is one or more of starch, carboxymethyl cellulose, and sodium humate, the anionic collector is one or two of sodium oleate and oxidized paraffin soap; the cationic collector is one or more of dodecylamine, tetradecylamine, coconut oil amine, and mixed amine.

[0016] Further, in step (3), the two scavenging stages include the first scavenging stage and the second scavenging stage. The pH is adjusted to 8 - 10.5 in the first scavenging stage.

[0017] Further, in step (5), the pH of the in-tank product 3 is adjusted to 6 - 7, and then it is thickened to a pulp concentration of 55% - 70% to obtain a high-concentration pulp. Then, the high-concentration pulp is adjusted to a concentration of 35% - 45% and then two roughing stages are carried out.

[0018] Further, in step (5), the specific methods of the two roughing stages and one scavenging stage are as follows: in the first roughing stage, an inhibitor, an activator, a collector, and a frother are added to obtain an in-tank product 7 and a foam product 7. The foam product 7 is used as the first rough concentrate; an activator, a collector, and a frother are added to the in-tank product 7 for the second roughing stage to obtain a bottom product 5 and a foam product 8. The foam product 8 is used as the second rough concentrate; a collector and a frother are added to the bottom product 5 for a scavenging operation to obtain a foam product 9 and tailings 4. The foam product 9 is returned to the second roughing stage. The first rough concentrate and the second rough concentrate are combined as the foam product 5.

[0019] Furthermore, for the blank beneficiation operation of the foam product 5 without adding any reagents, the foam mineral 1 is obtained; after adding an inhibitor, a collector, and a foaming agent to the foam mineral 1, the second beneficiation operation is carried out to obtain the foam mineral 2; the foam mineral 2 is subjected to 1-2 times of beneficiation by adding a collector and an inhibitor to obtain the foam product 6, and the foam product 6 is pyrochlore concentrate, and the underflow minerals in the beneficiation operation are returned to the previous operation.

[0020] Furthermore, in step (5), the flotation reagents and their dosages are as follows: 500-5000 g / t of activator, 10-500 g / t of inhibitor, 10-500 g / t of collector, 5-30 g / t of foaming agent; the activator is one or more of sodium fluorosilicate, sodium fluoride, and hydrofluoric acid, the inhibitor is one or more of sodium silicate, sodium hexametaphosphate, and sodium polyphosphate, the collector is one or more of dodecylamine, mixed amine, oil diamine, and quaternary ammonium salt, and the foaming agent is any one of pine oil, MIBC, butyl ether alcohol, and triethoxybutane.

[0021] Furthermore, in step (5), during the two rough selections, one scavenging, and 3-4 times of beneficiation, the pulp pH is adjusted to 3.5-5.5 each time for flotation.

[0022] The beneficial effects of the present invention:

[0023] Compared with the existing process, after grinding and magnetic separation to remove magnetic products in this application, the non-magnetic products are subjected to coarse and fine classification and then treated separately, that is, the coarse-grained minerals are treated by gravity separation, and the fine-grained minerals are treated by desliming, which improves the treatment efficiency before flotation and shortens the multi-stage desliming treatment process before conventional flotation; at the same time, combined with an inhibitor, a cationic and anionic mixed collector is used to remove carbonate minerals and mica together, shortening the flotation impurity removal process before pyrochlore flotation, avoiding the loss of pyrochlore minerals in this section of the operation. In addition, the present invention selects amines as the collector for pyrochlore and fluorine-containing compounds as the activator for pyrochlore, strengthening the flotation effect in the pyrochlore flotation section. This patent improves the grade and recovery rate of this type of pyrochlore concentrate by optimizing and simplifying the desliming method and the flotation impurity removal section, and strengthening the pyrochlore flotation section. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0025] Figure 1 It is a flotation recovery method for pyrochlore ore containing carbonate and mica of the present invention. Specific embodiments

[0026] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0027] Example 1

[0028] A certain pyrochlore raw ore, with the content of Nb 2 O 5 being 1.23%, where the main gangue minerals are calcite at 29.10%, dolomite at 10.35%, and biotite and mica at 19.84%.

[0029] As Figure 1 shown, the flotation recovery method of pyrochlore ore containing carbonate and mica of the present invention is carried out according to the following steps:

[0030] (1) The pyrochlore raw ore is crushed and then ground to a particle size of -0.074 mm with a mass ratio of 76.42% to obtain a grinding product. The grinding product is subjected to weak magnetic separation, i.e., magnetic separation at a magnetic field intensity of 0.15 T, to obtain magnetic products and non-magnetic products. Among them, the magnetic products can be discarded as tailings or enter the next iron beneficiation operation as by-product iron rough concentrate.

[0031] (2) The non-magnetic products after magnetic separation are subjected to primary classification by a hydrocyclone to obtain fine-grained minerals and coarse-grained minerals, with a classification particle size of 30 microns. The coarse-grained minerals are subjected to gravity separation by a spiral chute to obtain light minerals and heavy minerals, and the light minerals are discarded as tailings. The fine-grained minerals are de-sludged by a small-diameter hydrocyclone with a de-sludging particle size of 10 microns to obtain a coarser underflow product and a finer overflow product, and the overflow product is discarded as tailings.

[0032] (3) The heavy minerals and the underflow product obtained in step 2 are combined, and water is added to adjust the pulp to a suitable concentration of 40%. Then, sodium hydroxide is added to adjust the pulp pH = 9, and sodium silicate and oxidized paraffin soap are added for pulp adjustment and then one-stage flotation is carried out to obtain foam product 1 and cell product 1, where foam product 1 is discarded as tailings 2. In this step, the dosage of sodium silicate is 3000 g per ton of raw material, and the dosage of oxidized paraffin soap is 600 g per ton of raw material;

[0033] Add starch, as well as a mixed collector of oxidized paraffin soap and coconut oil amine to the product 1 in the cell, and carry out rough selection in the first stage after pulp mixing to obtain foam product 2 and cell product 2; among them, the starch dosage is 400 g per ton of raw material, the oxidized paraffin soap dosage is 400 g per ton of raw material, and the coconut oil amine dosage is 200 g per ton of raw material;

[0034] Add sodium hydroxide to cell product 2 to ensure that the pulp pH is about 8.5, continue to add starch, as well as a mixed collector of oxidized paraffin soap and coconut oil amine, and carry out scavenging in the first stage after pulp mixing. The obtained flotation foam is returned to the first-stage rough selection, and the cell product of the first-stage scavenging enters the next operation; among them, the starch dosage is 200 g per ton of raw material, the oxidized paraffin soap dosage is 200 g per ton of raw material, and the coconut oil amine dosage is 100 g per ton of raw material;

[0035] Add a mixed collector of oxidized paraffin soap and coconut oil amine to the cell product of the first-stage scavenging, and carry out scavenging in the second stage after pulp mixing. The obtained flotation foam is returned to the first-stage scavenging, and cell product 3 enters the next operation; among them, the oxidized paraffin soap dosage is 100 g per ton of raw material, and the coconut oil amine dosage is 80 g per ton of raw material.

[0036] (4) Carry out a blank cleaning on foam product 2 in step (3) without adding reagents to obtain foam product 4 and bottom product 4; foam product 4 is discarded as tailing 3, and bottom product 4 is returned to the first-stage rough selection;

[0037] (5) Adjust the pulp pH of the cell product 3 obtained by flotation in step (3) to 6 - 7 with sulfuric acid; then concentrate it to a pulp concentration of 60% with a thickener to obtain a high-concentration pulp;

[0038] Adjust the high-concentration pulp to a concentration of 38% by adding water for pulp mixing, add sulfuric acid to adjust the pulp pH to about 4, add sodium silicate as an inhibitor, add sodium fluorosilicate as an activator, add oil diamine collector and pine oil as a foaming agent for the first rough selection to obtain cell product 7 and foam product 7, and foam product 7 is rough concentrate one; among them, the sodium silicate dosage is 400 g per ton of raw material, the sodium fluorosilicate dosage is 3000 g per ton of raw material, the oil diamine dosage is 400 g per ton of raw material, and the pine oil dosage is 20 g per ton of raw material;

[0039] Continue to add sodium fluorosilicate, oil diamine and pine oil to cell product 7 for the second rough selection to obtain bottom product 5 and foam product 8, and foam product 8 is rough concentrate two; among them, the sodium fluorosilicate dosage is 1000 g per ton of raw material, the oil diamine dosage is 100 g per ton of raw material, and the pine oil dosage is 10 g per ton of raw material;

[0040] Add oil diamine and pine oil to bottom product 5 for one scavenging to obtain foam product 9 and tailing 4, and foam product 9 is returned to the second rough selection; among them, the oil diamine dosage is 100 g per ton of raw material, and the pine oil dosage is 5 g per ton of raw material;

[0041] Combine the first rough concentrate and the second rough concentrate as the foam product 5, and conduct the first cleaning operation without adding any reagents to obtain the underflow mineral 1 and the foam mineral 1; the underflow mineral 1 is returned to the first rough selection, and the foam mineral 1 is added with sodium silicate, and sulfuric acid is used to ensure that the pulp pH is below 5. After adding dioctylamine and pine oil and adjusting the pulp and stirring, conduct the second cleaning operation to obtain the underflow mineral 2 and the foam mineral 2; the underflow mineral 2 is returned to the first cleaning operation, where the dosage of sodium silicate is 400 g per ton of raw material, the dosage of dioctylamine is 50 g per ton of raw material, and the dosage of pine oil is 5 g per ton of raw material;

[0042] Add sodium silicate as an inhibitor to the foam mineral 2, then use sulfuric acid to ensure that the pulp pH is below 5, and then add dioctylamine to adjust the pulp and stir, and then conduct the third cleaning operation; obtain the foam mineral 3 and the underflow mineral 3, and the underflow mineral 3 is returned to the second cleaning operation; where the dosage of sodium silicate is 100 g per ton of raw material, and the dosage of dioctylamine is 20 g per ton of raw material;

[0043] Add sodium silicate as an inhibitor to the foam mineral 3, then use hydrochloric acid to ensure that the pulp pH is below 4, and then add dioctylamine to adjust the pulp and stir, and then conduct the fourth cleaning operation to obtain the foam product 6, and the foam product 6 is pyrochlore concentrate. The underflow mineral of this step is returned to the third cleaning operation, where the dosage of sodium silicate is 100 g per ton of raw material, and the dosage of dioctylamine is 10 g per ton of raw material.

[0044] The beneficiation results of the flotation recovery method of the present invention are shown in the following table

[0045] Product Name Yield (%) <![CDATA[Nb 2 O 5 Grade (%)]]> <![CDATA[Nb 2 O 5 Recovery rate (%)]]> Magnetic Product 17.65 0.201 2.88 Light Minerals 18.52 0.16 2.40 Overflow Product 17.01 0.35 4.83 Tailings 2 16.39 0.312 4.15 Tailings 3 9.39 0.51 3.89 Tailings 4 19.53 0.886 14.04 Pyrochlore Concentrate 1.51 55.36 67.82 Total 100.00 1.23 100.00

[0046] Comparative Example 1

[0047] The following process is used to recover the pyrochlore raw ore, and the specific method is as follows:

[0048] (1) The raw ore is ground to a particle size of less than 0.074 mm with a proportion of 75.3%. The ground ore product is subjected to a primary classification by a single-stage hydrocyclone to obtain coarse-grained minerals and fine-grained minerals. The coarse-grained minerals enter the next-stage hydrocyclone for secondary classification to obtain coarse-grained products and fine-grained products. The fine-grained products are returned to the previous classification operation, and the coarse-grained products enter the next operation; the fine-grained minerals enter the hydrocyclone for tertiary classification to obtain two products of coarse grains and fine grains. The coarse-grained products are returned to the primary classification operation, and the fine grains enter the hydrocyclone for two more classifications in the same way to obtain slime as tailings for discard. The coarse-grained products of each stage of classification operation are returned to the previous operation;

[0049] (2) Then, alkali is added to the classified products obtained from the classification operation to adjust the pulp alkalinity, starch inhibitor is added, and sodium oleate is used as a collector for carbonate flotation. After one rough selection, three fine selections, and two scavenging selections, carbonate minerals and in-cell products are obtained. The carbonate minerals are discarded as tailings, and the in-cell products enter the next operation level;

[0050] (3) Alkali is added to the in-cell products in step 2 to adjust to alkalinity, starch is added as an inhibitor, and dodecylamine is used as a collector for mica flotation. After one rough selection, two scavenging selections, and one fine selection, mica and in-cell products are obtained. The mica is discarded as tailings, and the in-cell products enter the next operation;

[0051] (4) The in-cell products in step 3 are subjected to magnetic separation with a magnetic separation intensity of 0.15 T to obtain magnetic substances and non-magnetic substances. The magnetic substances are processed as other products, and the non-magnetic products enter the next operation;

[0052] (5) For the in-cell products obtained in step 4, after concentration, clear water is added, and after adjusting to a suitable concentration, the pulp is adjusted to acidic conditions. With sodium silicate as an inhibitor and dodecylamine as a collector, pyrochlore concentrate and tailings are obtained after one rough selection, three scavenging selections, and four fine selections.

[0053] A certain pyrochlore raw ore is the same as that in Example 1, and the process of Comparative Example 1 is used for recovery, and a pyrochlore concentrate product with a grade of 52.34% and a recovery rate of 55.64% can be obtained.

[0054] Example 2

[0055] A certain pyrochlore raw ore, Nb 2 O 5 content is 1.63%. Among them, the main gangue minerals are calcite 25.10%, dolomite content 12.35%, and biotite and mica content 22.38%. Using the flotation recovery method for pyrochlore ore containing carbonate and mica of the present invention, the following steps are carried out:

[0056] (1) The pyrochlore raw ore is crushed and then ground to a particle size of -0.074 mm with a mass ratio of 70.46% to obtain a grinding product; the grinding product is subjected to weak magnetic separation, that is, magnetic separation under a magnetic field intensity of 0.15 T, to obtain magnetic products and non-magnetic products; among them, the magnetic products can be discarded as tailings or by-product iron rough concentrate enters the next iron beneficiation operation.

[0057] (2) The non-magnetic products after magnetic separation are subjected to primary classification using a hydrocyclone to obtain fine-grained minerals and coarse-grained minerals, with a classification particle size of 40 microns; the coarse-grained minerals are subjected to gravity separation using a spiral chute to obtain light minerals and heavy minerals, and the light minerals are discarded as tailings; the fine-grained minerals are de-slimed using a small-diameter hydrocyclone, with a de-sliming particle size of 15 microns, to obtain a coarser underflow product and a finer overflow product, and the overflow product is discarded as tailings.

[0058] (3) The heavy minerals and the underflow product obtained in step (2) are combined. When adding water to adjust the pulp to a suitable concentration of 45%, sodium hydroxide is added to adjust the pulp pH = 9, and sodium silicate and oxidized paraffin soap are added for pulp conditioning, followed by one-stage flotation to obtain froth product 1 and in-cell product 1, where froth product 1 is discarded as tailings 2; in this step, the dosage of sodium silicate is 2000 g per ton of raw materials, and the dosage of oxidized paraffin soap is 800 g per ton of raw materials;

[0059] Starch, and a mixed collector of oxidized paraffin soap and coconut amine are added to in-cell product 1 for pulp conditioning, followed by one-stage roughing to obtain froth product 2 and in-cell product 2; among them, the dosage of starch is 300 g per ton of raw materials, the dosage of oxidized paraffin soap is 400 g per ton of raw materials, and the dosage of coconut amine is 250 g per ton of raw materials;

[0060] Sodium hydroxide is added to in-cell product 2 to ensure that the pulp pH is around 9, and starch, and a mixed collector of oxidized paraffin soap and coconut amine are continuously added for pulp conditioning, followed by one-stage scavenging to obtain flotation froth returned to one-stage roughing, and the in-cell product of one-stage scavenging enters the next operation; among them, the dosage of starch is 100 g per ton of raw materials, the dosage of oxidized paraffin soap is 150 g per ton of raw materials, and the dosage of coconut amine is 100 g per ton of raw materials;

[0061] A mixed collector of oxidized paraffin soap and coconut amine is added to the in-cell product of one-stage scavenging for pulp conditioning, followed by two-stage scavenging to obtain flotation froth returned to one-stage scavenging, and in-cell product 3 enters the next operation; among them, the dosage of oxidized paraffin soap is 100 g per ton of raw materials, and the dosage of coconut amine is 50 g per ton of raw materials.

[0062] (4) Froth product 2 in step (3) is subjected to one-time blank cleaning without adding reagents to obtain froth product 4 and bottom product 4; froth product 4 is discarded as tailings, and bottom product 4 is returned to one-stage roughing;

[0063] (5) Hydrochloric acid is used to adjust the pulp pH of in-cell product 3 obtained by flotation in step (3) to 7; then it is concentrated to a pulp concentration of 65% using a thickener to obtain a high-concentration pulp;

[0064] The high-concentration pulp is adjusted to a concentration of 40% by adding water, hydrochloric acid is added to adjust the pulp pH to about 3.5, sodium polyphosphate is added as an inhibitor, sodium fluoride is added as an activator, dodecylamine collector and pine oil are added as frothers for the first rough selection to obtain the in-tank product 7 and the foam product 7. The foam product 7 is the first rough concentrate; among them, the dosage of sodium polyphosphate is 100 g per ton of raw material, the dosage of sodium fluoride is 1000 g per ton of raw material, the dosage of dodecylamine is 300 g per ton of raw material, and the dosage of pine oil is 20 g per ton of raw material;

[0065] The in-tank product 7 is continuously added with sodium fluoride, dodecylamine and pine oil for the second rough selection to obtain the bottom product 5 and the foam product 8. The foam product 8 is the second rough concentrate; among them, the dosage of sodium fluoride is 500 g per ton of raw material, the dosage of dodecylamine is 180 g per ton of raw material, and the dosage of pine oil is 5 g per ton of raw material;

[0066] The bottom product 5 is added with dodecylamine and pine oil for one scavenging to obtain the foam product 9 and the tailings 4. The foam product 9 is returned to the second rough selection; among them, the dosage of dodecylamine is 100 g per ton of raw material, and the dosage of pine oil is 5 g per ton of raw material;

[0067] The first rough concentrate and the second rough concentrate are combined as the foam product 5, and the first cleaning operation is carried out without adding any reagents to obtain the underflow mineral 1 and the foam mineral 1; the underflow mineral 1 is returned to the first rough selection, the foam mineral 1 is added with sodium polyphosphate inhibitor, hydrochloric acid is used to ensure that the pulp pH is below 5, dodecylamine and pine oil are added, and after pulp mixing and stirring, the second cleaning operation is carried out to obtain the underflow mineral 2 and the foam mineral 2; the underflow mineral 2 is returned to the first cleaning operation, among which the dosage of sodium polyphosphate is 50 g per ton of raw material, the dosage of dodecylamine is 60 g per ton of raw material, and the dosage of pine oil is 5 g per ton of raw material;

[0068] Sodium polyphosphate is added as an inhibitor to the foam mineral 2, then hydrochloric acid is used to ensure that the pulp pH is below 5, and then dodecylamine is added for pulp mixing and stirring, and then the third cleaning operation is carried out; the foam product 6 and the underflow mineral 3 are obtained, and the underflow mineral 3 is returned to the second cleaning operation; among them, the dosage of sodium polyphosphate is 30 g per ton of raw material, the dosage of dodecylamine is 30 g per ton of raw material, and the foam product 6 is the pyrochlore concentrate.

[0069] The ore dressing results of the flotation recovery method of the present invention are shown in the following table

[0070]

[0071]

[0072] Comparative Example 2

[0073] A certain pyrochlore raw ore is the same as that in Example 2, and the recovery process of Comparative Example 2 is the same as that of Comparative Example 1. A pyrochlore concentrate product with a grade of 55.41% and a recovery rate of 62.55% can be obtained.

[0074] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A flotation recovery method for pyrochlore ore containing carbonate and mica, characterized in that, it comprises the following steps: (1) The original pyrochlore ore is crushed and then ground to a particle size of -0.074 mm with a mass percentage of 65%-80% to obtain a ground product. The ground product is subjected to a first magnetic separation to obtain a magnetic product and a non-magnetic product, and the magnetic separation intensity is 0.1-0.2 T; (2) The non-magnetic product is subjected to a first classification operation with a classification particle size of 30-40 microns to obtain fine-grained minerals and coarse-grained minerals. The coarse-grained minerals are subjected to a gravity separation operation to obtain light minerals and heavy minerals. The fine-grained minerals are deslimed with a desliming particle size of 5-20 microns to obtain an underflow product and an overflow product. The overflow product and the light minerals are used as tailings 1; (3) The heavy minerals and the underflow product are combined and subjected to a first-stage flotation to obtain a froth product 1 and a cell product 1. The froth product 1 is used as tailings 2; The cell product 1 is subjected to a first-stage roughing to obtain a froth product 2 and a cell product 2. The cell product 2 is subjected to two-stage scavenging to obtain a cell product 3; (4) The froth product 2 obtained in step (3) is subjected to a first blank cleaning to obtain a froth product 4 and a cell bottom product 4. The froth product 4 is used as tailings 3, and the cell bottom product 4 is returned to the first-stage roughing; (5) The cell product 3 obtained in step (3) is concentrated, and then subjected to two-stage roughing to obtain a froth product 5 and a cell bottom product 5. The cell bottom product 5 is subjected to a single scavenging to obtain tailings 4; The froth product 5 is subjected to 3-4 times of cleaning to obtain a froth product 6, and the froth product 6 is the pyrochlore concentrate.

2. A flotation recovery method for pyrochlore ore containing carbonate and mica according to claim 1, characterized in that, in step (3), the specific method of the first-stage flotation is: adjusting the pulp concentration to 35-45%, the pH to 8-10.5, and then adding 500-5000 g / t of inhibitor and 200-1000 g / t of anionic collector for flotation. The inhibitor is one or more of sodium silicate, starch, and carboxymethyl cellulose, and the anionic collector is one or more of sodium oleate, oxidized paraffin soap, sodium petroleum sulfonate, and alkyl sulfonate.

3. A flotation recovery method for pyrochlore ore containing carbonate and mica according to claim 1, characterized in that, in step (3), in the first-stage roughing and the two-stage scavenging, the flotation reagents and their dosages are: 100-600 g / t of inhibitor, 100-500 g / t of anionic collector, 50-300 g / t of cationic collector. As the flotation operation progresses, the dosage of the anionic collector gradually decreases; The inhibitor is one or more of starch, carboxymethyl cellulose, and sodium humate, the anionic collector is one or two of sodium oleate and oxidized paraffin soap; The cationic collector is one or more of dodecylamine, tetradecylamine, coconut oil amine, and mixed amine.

4. A flotation recovery method for pyrochlore ore containing carbonate and mica according to any one of claims 1-3, characterized in that, in step (3), the two-stage scavenging includes a first-stage scavenging and a second-stage scavenging, and the pH is adjusted to 8-10.5 in the first-stage scavenging.

5. The flotation recovery method of a pyrochlore ore containing carbonate and mica according to claim 1, characterized in that, in step (5), the pH of the product 3 in the cell is adjusted to 6 - 7, then concentrated to a pulp concentration of 55% - 70% to obtain a high-concentration pulp, and then the high-concentration pulp is adjusted to a concentration of 35% - 45%, and then two rough selections are carried out.

6. The flotation recovery method of a pyrochlore ore containing carbonate and mica according to claim 1, characterized in that, in step (5), the specific methods of two rough selections and one scavenging are as follows: in the first rough selection, an inhibitor, an activator, a collector and a foaming agent are added to obtain the product 7 in the cell and the foam product 7, and the foam product 7 is used as the first rough concentrate; an activator, a collector and a foaming agent are added to the product 7 in the cell for the second rough selection to obtain the bottom product 5 and the foam product 8, and the foam product 8 is used as the second rough concentrate; a collector and a foaming agent are added to the bottom product 5 for one scavenging to obtain the foam product 9 and the tailings 4, and the foam product 9 is returned to the second rough selection, and the first rough concentrate and the second rough concentrate are combined as the foam product 5.

7. The flotation recovery method of a pyrochlore ore containing carbonate and mica according to claim 6, characterized in that, the foam product 5 is subjected to a blank cleaning operation to obtain the foam mineral 1; the inhibitor, the collector and the foaming agent are added to the foam mineral 1 and then the second cleaning operation is carried out to obtain the foam mineral 2; the collector and the inhibitor are added to the foam mineral 2 for 1 - 2 times of cleaning to obtain the foam product 6, and the foam product 6 is the pyrochlore concentrate, and the underflow minerals in the cleaning operation are returned to the previous operation.

8. The flotation recovery method of a pyrochlore ore containing carbonate and mica according to claim 7, characterized in that, in step (5), the flotation reagents and their dosages are as follows: 500 - 5000 g / t of activator, 10 - 500 g / t of inhibitor, 10 - 500 g / t of collector, 5 - 30 g / t of foaming agent; the activator is one or more of sodium fluorosilicate, sodium fluoride and hydrofluoric acid, the inhibitor is one or more of sodium silicate, sodium hexametaphosphate and sodium polyphosphate, the collector is one or more of dodecylamine, mixed amine, oil diamine and quaternary ammonium salt, and the foaming agent is any one of pine oil, MIBC, butyl ether alcohol and triethoxybutane.

9. The flotation recovery method of a pyrochlore ore containing carbonate and mica according to claim 1, characterized in that, in step (5), in the two rough selections, one scavenging and 3 - 4 times of cleaning, the pulp pH is adjusted to 3.5 - 5.5 each time of flotation.

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