A method for separating iron-phosphorus polymetallic ore by magnetic suspension
Patent Information
- Application Number
- CN202611218895.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-08-12
- Publication Date
- 2026-10-30
AI Technical Summary
采用单一磁选工艺难以获得合格铁精矿，且会损失磷矿物；单一浮选工艺则受铁矿物干扰，药剂消耗大，磷精矿品位和回收率低
（1）通过三段一闭路破碎和阶段磨矿、多段磁选-再磨闭路，有效避免过磨和泥化，实现了铁矿物阶段解离和梯次富集，入磨粒度与磨矿效率得到优化。 （2）高频筛分级与二段磁选、再磨闭路相结合，使未充分解离的连生体返回再磨，保证了后续三段磁选和磁场精选的给料粒度及解离度。 （3）采用磁场精选对三段磁选精矿进一步提纯，中矿闭路返回，稳定获得高品位铁精矿（品位≥65%），且流程中磁选尾矿性质稳定。 （4）对磁选尾矿进行浓缩后反浮选脱硫，预先脱除硫化矿物，既避免了硫化物对磷浮选药剂的消耗和泡沫状态的干扰，又为硫化矿物的综合回收创造了条件；脱硫尾矿进入磷浮选，采用“一粗一扫多精”闭路流程，可稳定获得高品位磷精矿（品位≥33%）。 （5）整个方法将破碎、阶段磨矿、磁选、磁场精选、脱硫浮选和磷浮选整合为连续稳定的磁浮联合分选体系，实现了铁、磷、硫的高效分步回收，指标好，适应性强。
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Figure CN122999367A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of mineral processing technology and relates to a magnetic levitation combined sorting method, particularly a magnetic levitation combined sorting method for iron-phosphorus polymetallic ores. Background Technology
[0002] In polymetallic iron-phosphate ores, the intergrowth relationships of iron minerals (such as magnetite and hematite), phosphorus minerals (such as apatite), and sulfide minerals (such as pyrite and chalcopyrite) are complex and closely associated. Using a single magnetic separation process is insufficient to obtain qualified iron concentrate and results in the loss of phosphorus minerals; a single flotation process is affected by iron mineral interference, leading to high reagent consumption and low phosphorus concentrate grade and recovery. If the ore is finely ground to full liberation in a single step, over-grinding and mud formation can easily occur, increasing energy consumption and affecting subsequent separation efficiency; conversely, insufficient grinding fineness will result in incomplete liberation of individual iron minerals, making it difficult to achieve the required iron concentrate grade. Furthermore, if residual sulfide minerals and coarse-grained materials in the magnetic separation tailings are directly fed into phosphorus flotation, it will deteriorate the flotation environment and affect the selectivity and reagent stability of phosphorus flotation. Current processes lack a stable, continuous, industrially integrated separation system that organically connects iron, phosphorus, and sulfur separation units. Summary of the Invention
[0003] The purpose of this invention is to address the aforementioned problems in existing technologies by proposing a magnetic levitation combined separation method for iron-phosphorus polymetallic ores. The technical problem to be solved by this invention is: how to achieve efficient recovery of iron concentrate and phosphorus concentrate through the coordinated configuration of crushing and screening, staged grinding, multi-stage magnetic separation, magnetic field cleaning, desulfurization of magnetic separation tailings and phosphorus flotation, while also taking into account the removal and recovery of associated sulfide minerals, with strong process adaptability and stable product indicators.
[0004] The objective of this invention can be achieved through the following technical solutions: A magnetic levitation combined separation method for iron-phosphorus polymetallic ores includes the following steps: S1, Three-stage closed-circuit crushing and screening The raw ore is processed by coarse crushing, medium crushing, fine crushing and screening. The qualified material under the screen enters the grinding bin, and the coarse particles over the screen are returned to the fine crushing, forming a closed-circuit crushing and screening process. The preferred qualified particle size entering the grinding is less than 12 mm. S2, First-stage grinding - first-stage magnetic separation for preliminary enrichment Qualified materials enter the first-stage ball mill for grinding. The grinding products are classified, with coarse particles returned to the first-stage grinding and qualified products entering the first-stage magnetic separation. The magnetic separation concentrate from the first stage enters the high-frequency screen and subsequent regrinding and re-selection system, while the magnetic separation tailings from the first stage enter the screening, concentration, desulfurization and phosphorus flotation system. S3, High-frequency screening and grading - two-stage magnetic separation - two-stage regrinding closed circuit The first-stage magnetic separation concentrate is classified by a high-frequency screen. The qualified fine particles with a diameter of 0.15mm pass through the screen enter the third-stage magnetic separation; the coarse particles pass through the screen enter the second-stage magnetic separation. The second-stage magnetic separation concentrate is then refmilled in a second-stage ball mill. The refmilled product is returned to the high-frequency screen for reclassification. S4, Three-stage magnetic separation - magnetic field fine selection The qualified products under the high-frequency screen enter the three-stage magnetic separation. The concentrate from the three-stage magnetic separation enters the magnetic field cleaning equipment. The cleaned concentrate is filtered and dewatered to obtain iron concentrate. The middlings from the magnetic field cleaning are returned to the two-stage magnetic separation or regrinding process. S5. Magnetic separation tailings screening, concentration, and reverse flotation desulfurization After being processed by linear screen, dewatering screen and inclined plate thickening unit, the concentrated underflow enters reverse flotation desulfurization to remove sulfide minerals. The desulfurization foam enters the sulfur resource recovery or copper-sulfur separation process, and the desulfurization tailings enter the phosphorus flotation. S6, phosphorus flotation recovery After being treated and slurry-modified, the desulfurized tailings enter the phosphorus flotation process, which adopts a closed-circuit process consisting of roughing, scavenging and multi-stage cleaning. The cleaned froth is concentrated and filtered to obtain phosphorus concentrate. S7, Recovery of Associated Sulfide Minerals For desulfurization foam containing high levels of copper and sulfide minerals, copper concentrate or sulfur concentrate can be obtained through regrinding, slurry preparation, copper-sulfur separation flotation, fine cleaning, and filtration dewatering.
[0005] Preferably, in step S7, the concentration of the slurry is 60%-70%, the pH of the slurry is adjusted to 9, and lime, collector T310 100g / t and YA inhibitor 100g / t are added during slurry preparation.
[0006] Preferably, the copper-sulfur separation adopts a "one coarse, two scavenging, four refining" method, and the sulfur refining adopts a "one coarse, two scavenging, one refining" method.
[0007] Preferably, in step S1, by adjusting the crushing and screening parameters, the proportion of -10 mm particles in the crushed product reaches more than 80%.
[0008] Preferably, in step S1, the coarse crushing discharge particle size is 100-300mm, the medium crushing discharge particle size is 20-50mm, and the fine crushing discharge particle size is 8-15mm.
[0009] Preferably, the grading standard for the grinding product in step S2 is a particle size of less than 4.0-5.0 mm.
[0010] Preferably, in step S4, when removing sulfide minerals, 100 g / t of collector xanthate and 5-10 g / t of frother are added.
[0011] Preferably, in step S6, when adding the drug and preparing the slurry, the raw material ratio of the collector is: new M soap base: old M soap base: oxidized paraffin soap 11:3:1, and the dispersant is water glass 250g / t.
[0012] Preferably, in step S7, the fineness of the regrinding discharge is required to be above -200 mesh (90%), the copper concentrate grade is above 12%, the tailings grade is below 0.03%, the sulfur concentrate grade is above 47%, and the tailings grade is below 0.3%.
[0013] Preferably, the coarse selection, sweep selection and multi-stage fine selection in step S6 adopt the "one coarse, two sweeps and two fine" mode.
[0014] Compared with existing technologies, this magnetic levitation combined separation method for iron-phosphorus polymetallic ores has the following advantages: (1) Through three-stage closed-circuit crushing and staged grinding, and multi-stage magnetic separation-regrinding closed-circuit, over-grinding and mud formation are effectively avoided, and the staged liberation and tiered enrichment of iron minerals are achieved, and the feed particle size and grinding efficiency are optimized. (2) The combination of high-frequency screening classification with two-stage magnetic separation and regrinding closed-circuit allows the incompletely liberated intergrowths to be returned to regrinding, ensuring the feed particle size and degree of liberation for subsequent three-stage magnetic separation and magnetic field cleaning. (3) Magnetic field cleaning is used to further purify the three-stage magnetic separation concentrate, and the middlings are returned in a closed-circuit manner, stably obtaining high-grade iron concentrate (grade ≥65%), and the properties of the magnetic separation tailings in the process are stable. (4) After the magnetic separation tailings are concentrated, reverse flotation is used for desulfurization to remove sulfide minerals in advance. This avoids the consumption of phosphorus flotation reagents and the interference of foam state by sulfides, and creates conditions for the comprehensive recovery of sulfide minerals. The desulfurized tailings enter the phosphorus flotation and adopt a closed-loop process of "one roughing, one scavenging and multiple cleaning" to stably obtain high-grade phosphorus concentrate (grade ≥33%). (5) The whole method integrates crushing, stage grinding, magnetic separation, magnetic field cleaning, desulfurization flotation and phosphorus flotation into a continuous and stable magnetic flotation combined separation system, realizing the efficient stepwise recovery of iron, phosphorus and sulfur, with good indicators and strong adaptability. Attached Figure Description
[0015] Figure 1 This is a flowchart of the method of the present invention.
[0016] Figure 2 This is a flowchart of the magnetic levitation combined sorting process in this invention.
[0017] Figure 3 This is a flowchart of the copper-sulfur separation and sulfur refining process in this invention.
[0018] Figure 4 This is a table of key indicators for the raw ore and products in this invention.
[0019] Figure 5 This is a table comparing the sorting indicators of the embodiments and comparative examples in this invention. Detailed Implementation
[0020] The following are specific embodiments of the present invention, which are described in conjunction with the accompanying drawings. However, the present invention is not limited to these embodiments.
[0021] Example A magnetic levitation combined separation method for iron-phosphorus polymetallic ore, wherein the raw ore has an iron grade of approximately 15%, a P2O5 grade of approximately 2.0%–2.1%, and contains a small amount of associated sulfide minerals (sulfur grade of approximately 0.85%). The method of this invention includes the following steps: S1, Three-stage closed-circuit crushing and screening The raw ore is processed by coarse crushing, medium crushing, fine crushing and screening. The qualified material under the screen enters the grinding bin, and the coarse particles over the screen are returned to the fine crushing, forming a closed-circuit crushing and screening process. The preferred qualified particle size entering the grinding is less than 12 mm. S2, First-stage grinding - first-stage magnetic separation for preliminary enrichment Qualified materials enter the first-stage ball mill for grinding. The grinding products are classified, with coarse particles returned to the first-stage grinding and qualified products entering the first-stage magnetic separation. The magnetic separation concentrate from the first stage enters the high-frequency screen and subsequent regrinding and re-selection system, while the magnetic separation tailings from the first stage enter the screening, concentration, desulfurization and phosphorus flotation system. S3, High-frequency screening and grading - two-stage magnetic separation - two-stage regrinding closed circuit The first-stage magnetic separation concentrate is classified by a high-frequency screen. The qualified fine particles under the screen enter the third-stage magnetic separation; the coarse particles over the screen enter the second-stage magnetic separation. The second-stage magnetic separation concentrate enters the second-stage ball mill for regrinding, and the regrinded product is returned to the high-frequency screen for reclassification. S4, Three-stage magnetic separation - magnetic field fine selection The qualified product under the high-frequency screen enters the three-stage magnetic separation. The concentrate from the three-stage magnetic separation enters the magnetic field cleaning equipment. The cleaned concentrate is filtered and dewatered to obtain iron concentrate. The middlings from the magnetic field cleaning are returned to the two-stage magnetic separation or regrinding process. The first stage is the two-stage magnetic separation, which reduces the burden on the two-stage ball mill. Some gangue and fine mud are first thrown into the tailings (suitable for cases with fewer intergrowths). The second stage is the ball mill, which solves the problem of intergrowths and reduces the loss of target iron minerals (suitable for cases with many intergrowths). S5. Magnetic separation tailings screening, concentration, and reverse flotation desulfurization After being processed by linear screen, dewatering screen and inclined plate thickening units, the concentrated underflow enters reverse flotation desulfurization to remove sulfide minerals. The desulfurization foam enters the sulfur resource recovery or copper-sulfur separation process, and the desulfurization tailings enter the phosphorus flotation.
[0022] S6, phosphorus flotation recovery After being treated and slurry-modified, the desulfurized tailings enter the phosphorus flotation process, which adopts a closed-circuit process consisting of roughing, scavenging and multi-stage cleaning. The cleaned froth is concentrated and filtered to obtain phosphorus concentrate. S7, Recovery of Associated Sulfide Minerals For desulfurization foam containing high levels of copper and sulfide minerals, copper concentrate or sulfur concentrate can be obtained through regrinding, slurry preparation, copper-sulfur separation flotation, fine cleaning, and filtration dewatering.
[0023] Preferably, in step S7, the concentration of the slurry is 60%-70%, the pH of the slurry is adjusted to 9, and lime, collector T310 100g / t and YA inhibitor 100g / t are added during slurry preparation.
[0024] Preferably, the copper-sulfur separation adopts a "one coarse, two scavenging, four refining" method, and the sulfur refining adopts a "one coarse, two scavenging, one refining" method.
[0025] Preferably, in step S1, by adjusting the crushing and screening parameters, the proportion of -10 mm particles in the crushed product reaches more than 80%.
[0026] Preferably, in step S1, the coarse crushing discharge particle size is 100-300mm, the medium crushing discharge particle size is 20-50mm, and the fine crushing discharge particle size is 8-15mm.
[0027] Preferably, the grading standard for the grinding product in step S2 is a particle size of less than 4.0-5.0 mm.
[0028] Preferably, in step S4, when removing sulfide minerals, 100 g / t of collector xanthate and 5-10 g / t of frother are added.
[0029] Preferably, in step S6, when adding the drug and preparing the slurry, the raw material ratio of the collector is: new M soap base: old M soap base: oxidized paraffin soap 11:3:1, and the dispersant is water glass 250g / t.
[0030] Preferably, in step S7, the fineness of the regrinding discharge is required to be above -200 mesh (90%), the copper concentrate grade is above 12%, the tailings grade is below 0.03%, the sulfur concentrate grade is above 47%, and the tailings grade is below 0.3%.
[0031] Preferably, the coarse selection, sweep selection and multi-stage fine selection in step S6 adopt the "one coarse, two sweeps and two fine" mode.
[0032] Key indicators of raw ore and final product, such as Figure 4 As shown.
[0033] Comparative Example 1 (single-stage grinding followed by fine grinding + single magnetic separation + flotation without desulfurization) A conventional combined process of grinding, magnetic separation, and flotation was adopted: the raw ore was crushed to less than 12 mm, and the first-stage grinding directly ground to a fineness of -200 mesh (70%). A single magnetic separation yielded iron concentrate. The tailings from the magnetic separation were not desulfurized and directly entered the phosphorus flotation process (one roughing, one scavenging, and three cleaning stages), with reagent conditions the same as in Example 1. The resulting iron concentrate grade was only 58.2%, and the phosphorus concentrate P2O5 grade was 27.6%. The phosphorus flotation froth was sticky and unstable, and reagent consumption increased by approximately 35% compared to Example 1.
[0034] Comparative Example 2 (without high-frequency screening and two-stage regrinding closed circuit) Based on the previous embodiment, the process eliminates high-frequency screening and the two-stage magnetic separation-regrinding closed-circuit. The concentrate from the first-stage magnetic separation is directly fed into the third-stage magnetic separation, and the concentrate from the third-stage magnetic separation then enters the magnetic field for further cleaning. The resulting iron concentrate grade decreases to 63.1%, the middlings recycling volume increases, and the system processing capacity decreases by approximately 12%.
[0035] Comparative Example 3 (Selected without magnetic field) The same crushing, staged grinding, and magnetic separation process as in the previous example was adopted, but the magnetic field refining step was omitted, and the three-stage magnetic separation concentrate was directly filtered as the final iron concentrate. The resulting iron concentrate had a grade of 62.4%, which could not meet the quality requirement of 65%.
[0036] Comparative Example 4 (Magnetic separation tailings directly subjected to phosphorus flotation without desulfurization) The same crushing, grinding, and magnetic separation processes as in the previous example were used, but the reverse flotation desulfurization step was omitted, and all magnetic separation tailings were directly fed into the phosphate flotation. The final phosphate concentrate grade decreased to 29.1%, flotation reagent consumption increased by approximately 40%, the froth layer became unstable, and operation became difficult.
[0037] The examples are compared with the sorting indicators of each comparative example, such as... Figure 5 As shown.
[0038] Depend on Figure 5 It can be seen that the present invention, through the combination of staged grinding-high frequency screening closed circuit, magnetic field cleaning and pre-reverse flotation desulfurization, can stabilize the iron concentrate grade at more than 65% and the phosphate concentrate grade at more than 33%, and has low reagent consumption and stable flotation foam, which is significantly better than the comparative scheme that lacks key steps.
[0039] As can be seen from the above embodiments, comparative examples and tables, the synergistic effect of each link in the magnetic levitation combined separation system constructed by the present invention effectively solves the problem of efficient separation and recovery of iron-phosphorus polymetallic ores, and has outstanding technical advantages.
[0040] The specific embodiments described herein are merely illustrative of the spirit of the invention. Those skilled in the art to which this invention pertains may make various modifications or additions to the described specific embodiments or use similar methods to substitute them, without departing from the spirit of the invention or exceeding the scope defined by the appended claims.
Claims
1. A magnetic levitation combined sorting method for iron-phosphorus polymetallic ores, characterized in that, Includes the following steps: S1, Three-stage closed-circuit crushing and screening The raw ore is processed by coarse crushing, medium crushing, fine crushing and screening. The qualified material under the screen enters the grinding bin, and the coarse particles over the screen are returned to the fine crushing, forming a closed-circuit crushing and screening process. The preferred qualified particle size entering the grinding is less than 12 mm. S2, First-stage grinding - first-stage magnetic separation for preliminary enrichment Qualified materials enter the first-stage ball mill for grinding. The grinding products are classified, with coarse particles returned to the first-stage grinding and qualified products entering the first-stage magnetic separation. The magnetic separation concentrate from the first stage enters the high-frequency screen and subsequent regrinding and re-selection system, while the magnetic separation tailings from the first stage enter the screening, concentration, desulfurization and phosphorus flotation system. S3, High-frequency screening and grading - two-stage magnetic separation - two-stage regrinding closed circuit The first-stage magnetic separation concentrate is classified by a high-frequency screen. The qualified fine particles with a diameter of 0.15mm pass through the screen enter the third-stage magnetic separation; the coarse particles pass through the screen enter the second-stage magnetic separation. The second-stage magnetic separation concentrate is then refmilled in a second-stage ball mill. The refmilled product is returned to the high-frequency screen for reclassification. S4, Three-stage magnetic separation - magnetic field fine selection The qualified products under the high-frequency screen enter the three-stage magnetic separation. The concentrate from the three-stage magnetic separation enters the magnetic field cleaning equipment. The cleaned concentrate is filtered and dewatered to obtain iron concentrate. The middlings from the magnetic field cleaning are returned to the two-stage magnetic separation or regrinding process. S5. Magnetic separation tailings screening, concentration, and reverse flotation desulfurization After being processed by linear screen, dewatering screen and inclined plate thickening unit, the concentrated underflow enters reverse flotation desulfurization to remove sulfide minerals. The desulfurization foam enters the sulfur resource recovery or copper-sulfur separation process, and the desulfurization tailings enter the phosphorus flotation. S6, phosphorus flotation recovery After being treated and slurry-modified, the desulfurized tailings enter the phosphorus flotation process, which adopts a closed-circuit process consisting of roughing, scavenging and multi-stage cleaning. The cleaned froth is concentrated and filtered to obtain phosphorus concentrate. S7, Recovery of Associated Sulfide Minerals For desulfurization foam containing high levels of copper and sulfide minerals, copper concentrate or sulfur concentrate can be obtained through regrinding, slurry preparation, copper-sulfur separation flotation, fine cleaning, and filtration dewatering.
2. The magnetic levitation combined separation method for iron-phosphorus polymetallic ore according to claim 1, characterized in that, In step S7, the concentration of the slurry is 60%-70%, the pH of the slurry is adjusted to 9, and lime, collector T310 100g / t and YA inhibitor 100g / t are added during slurry preparation.
3. The magnetic levitation combined separation method for iron-phosphorus polymetallic ore according to claim 1, characterized in that, The copper-sulfur separation process employs a "one roughing, two scavenging, four refining" method, while the sulfur refining process employs a "one roughing, two scavenging, one refining" method.
4. The magnetic levitation combined separation method for iron-phosphorus polymetallic ore according to claim 1, characterized in that, In step S1, by adjusting the crushing and screening parameters, the proportion of -10 mm particles in the crushed product reaches more than 80%.
5. The magnetic levitation combined separation method for iron-phosphorus polymetallic ore according to claim 1, characterized in that, In step S1, the coarse crushing discharge particle size is 100-300mm, the medium crushing discharge particle size is 20-50mm, and the fine crushing discharge particle size is 8-15mm.
6. The magnetic levitation combined separation method for iron-phosphorus polymetallic ore according to claim 1, characterized in that, In step S2, the grading standard for the grinding product is a particle size of less than 4.0-5.0 mm.
7. The magnetic levitation combined separation method for iron-phosphorus polymetallic ore according to claim 1, characterized in that, In step S4, when removing sulfide minerals, 100 g / t of xanthate collector and 5-10 g / t of frother are added.
8. The magnetic levitation combined separation method for iron-phosphorus polymetallic ore according to claim 1, characterized in that, In step S6, when adding medicine and preparing the slurry, the collector and the raw material ratio of the collector are: new M soap base: old M soap base: oxidized paraffin soap 11:3:1, and the dispersant is water glass 250g / t.
9. The magnetic levitation combined separation method for iron-phosphorus polymetallic ore according to claim 1, characterized in that, In step S7, the fineness requirements for regrinding discharge are -200 mesh or higher (90%), copper concentrate grade is 12% or higher (12%), tailings grade is 0.03% or lower, sulfur concentrate grade is 47% or higher (47%), and tailings grade is 0.3% or lower.
10. The magnetic levitation combined sorting method for iron-phosphorus polymetallic ore according to claim 1, characterized in that, In step S6, the coarse selection, sweep selection, and multi-segment fine selection adopt the "one coarse, two sweeps, two fine" mode.