A method for enhanced separation and purification of complex and difficult-to-process titanium sand ore

Abstract

This invention belongs to the field of mineral processing technology, specifically relating to a method for enhanced separation and purification of complex and difficult-to-process titanium sand ore. The invention involves pretreatment, scrubbing, and coarse separation using a cleaning agent to obtain narrow-particle-size materials; then wet gravity separation is performed to obtain wet zircon rough concentrate and rutile rough concentrate; subsequently, the wet zircon rough concentrate and rutile rough concentrate are subjected to dehydration-controlled oxygen thermal activation, respectively; finally, the oxygen-controlled thermally activated zircon rough concentrate and rutile rough concentrate are subjected to weak magnetic-strong magnetic-electrostatic separation, respectively, to obtain high-quality zircon concentrate, rutile concentrate, monazite concentrate, iron-bearing rutile concentrate, titanium concentrate, and other products. The enhanced separation and purification method provided by this invention can effectively remove fine-grained capping material from the surface of the target minerals, reduce the feed amount of gangue minerals entering the dehydration-drying-electrostatic separation process, integrate an oxygen-controlled thermal activation unit, eliminate alternating wet and dry separation and repeated dehydration and drying, and achieve improved system production efficiency and energy saving.

Description

Technical Field

[0001] This invention belongs to the field of mineral processing technology, specifically relating to a method for enhanced separation and purification of complex and difficult-to-process titanium sand ore. Background Technology

[0002] With the development of industries such as aerospace, communications, military, and nuclear energy, the demand for titanium metal is gradually increasing. Simultaneously, with the development and high marketization of the welding materials industry, my country has become the world's largest producer and consumer of welding materials. Rutile is a crucial raw material for metallic titanium and welding materials, and only high-quality rutile can be used to produce high-quality titanium materials and high-grade welding materials. Currently, high-quality rutile mainly comes from titanium sand ore.

[0003] Titanium sand ore is mainly composed of ilmenite, rutile, zircon, monazite, and garnet, and is a natural resource with high comprehensive utilization value. Currently, the beneficiation process mostly involves spiral flow and shaking tables for initial separation and enrichment, followed by drying and further processing using dry magnetic separation and electrostatic separation. However, this process suffers from problems such as alternating wet and dry processes, poor continuity, and repeated separation. With the continuous exploitation of domestic titanium sand ore resources, the original ore deposits are gradually becoming leaner, finer, and more complex, rendering existing beneficiation technologies and equipment unsuitable for processing current titanium sand ore.

[0004] To address the above issues, Chinese patent CN202310217242.5 discloses a method for scrubbing target minerals. This method enhances the removal of slime by adding a scrubbing agent to the scrubbing machine and incorporates a separation and concentration system, improving the cleaning and desliming efficiency of the target minerals. However, since the scrubbing agent is added directly to the scrubbing machine, it is difficult to ensure that the reagent can function effectively. Chinese patent ZL201110235944.3 uses microwave pretreatment of rutile to selectively melt metallic iron and iron oxide from the ore. After grinding and magnetic separation, a rutile concentrate with a TiO2 content greater than 90% can be obtained, meeting the feed requirements for titanium dioxide production using the hydrochloric acid or sulfuric acid process. However, the grinding energy consumption after microwave roasting is relatively high. Chinese patent ZL202010356226.0 describes a microwave heating pretreatment method for rutile rough concentrate, followed by electrostatic separation to obtain rutile concentrate with a TiO2 content greater than 90%. However, the patent describes rutile rough concentrate with a TiO2 content of over 80% as the raw material, requiring conventional beneficiation processes to produce the rough concentrate before implementation, resulting in a lengthy process. Therefore, there is an urgent need to develop a new method for enhanced separation and purification of complex and difficult-to-process titanium sand ores. Summary of the Invention

[0005] The purpose of this invention is to provide a method for enhanced separation and purification of complex and difficult-to-process titanium sand ore. The method provided by this invention can obtain a variety of high-quality zircon concentrate, rutile concentrate, monazite concentrate, iron-bearing rutile concentrate and titanium concentrate, and can effectively improve system production efficiency and save energy and reduce consumption.

[0006] To achieve the above objectives, the present invention provides the following technical solution: This invention provides a method for enhanced separation and purification of titanium sand ore, comprising the following steps: The titanium sand ore is mixed with a cleaning agent solution for pretreatment to obtain pretreated ore. The pretreated raw ore is mixed with water to form a slurry; the slurry is then scrubbed to obtain a scrubbed slurry. The scrubbing slurry is deslimed by passing it through a dewatering screen to obtain the oversize and undersize material. The material on the dewatering screen is subjected to coarse screening to obtain coarse screening oversize and coarse screening undersize; the screen aperture of the coarse screening is ≥0.15mm; The material screened by the coarse screen is fed into the first-stage spiral sluice for separation to obtain the first zircon rough concentrate, the first-stage spiral sluice middlings, and the first tailings; the first-stage spiral sluice middlings are fed into the first-stage fine sand shaking table for separation to obtain the second zircon rough concentrate, the first-stage fine sand shaking table middlings, and the second tailings; the first zircon rough concentrate and the second zircon rough concentrate are combined to obtain the zircon rough concentrate. The zircon rough concentrate and the middlings from the first-stage fine sand shaking table are respectively fed into the second-stage fine sand shaking table for separation. After separation, the zircon rough concentrate yields wet zircon rough concentrate and third tailings. After separation, the middlings from the first-stage fine sand shaking table yields wet gold rough concentrate and fourth tailings. The wet zircon rough concentrate and the wet rutile rough concentrate are dehydrated separately, and then subjected to controlled-oxygen thermal activation in an oxygen-containing gas to obtain dry zircon rough concentrate and dry rutile rough concentrate, respectively; the oxygen-containing gas contains oxygen, and the mass content of oxygen in the oxygen-containing gas is 5-25%. The dry zircon rough concentrate and the dry rutile rough concentrate are respectively subjected to dry weak magnetic separation. After separation, the dry zircon rough concentrate yields a first weak magnetic separation magnetic product and a first weak magnetic separation tailings. After separation, the dry rutile rough concentrate yields a second weak magnetic separation magnetic product and a second weak magnetic separation tailings. The magnetic field strength of the dry weak magnetic separation is ≤0.4T. The tailings from the first and second weak magnetic separations are subjected to dry strong magnetic separation. The tailings from the first weak magnetic separation are separated to obtain monazite rough concentrate and the tailings from the first strong magnetic separation. The tailings from the second weak magnetic separation are separated to obtain the first iron-bearing rutile concentrate and the tailings from the second strong magnetic separation. The magnetic field strength of the dry strong magnetic separation is ≥0.7T. The monazite rough concentrate, the first strong magnetic separation tailings and the second strong magnetic separation tailings are respectively subjected to electrostatic separation; the electrostatic separation system used when the monazite rough concentrate is subjected to electrostatic separation includes drum electrostatic separation and screen plate electrostatic separation in sequence, and the monazite rough concentrate is separated to obtain monazite concentrate and second iron-bearing rutile concentrate. The electrostatic separation systems used for electrostatic separation of the first and second strong magnetic separation tailings respectively include, in sequence, drum electrostatic separation, arc plate electrostatic separation, and screen plate electrostatic separation. Zircon concentrate is obtained after the first strong magnetic separation tailings, and rutile concentrate is obtained after the second strong magnetic separation tailings. The first strong magnetic separation tailings are further processed by the drum electrostatic separation operation to obtain the first electrostatic separation tailings, which are then returned to the second weak magnetic separation tailings for dry strong magnetic separation feeding. The second strong magnetic separation tailings are further processed by the drum electrostatic separation operation to obtain a second electrostatic separation tailings; the second electrostatic separation tailings are returned to the first weak magnetic separation tailings for dry strong magnetic separation feeding.

[0007] Preferably, the titanium sand ore comprises the following components by mass content: TiO2: 29~35%, ZrO2: 4~8%, Fe: 4.5~8.5%, SiO2: 33~40%, P: 0.1~1.0%; the cleaning agent solution comprises a cleaning agent and water, the cleaning agent comprises one or more of dibasic organic acids, ternary organic acids, and inorganic acids; the mass content of the cleaning agent in the cleaning agent solution is 10~40%; the amount of the cleaning agent solution used is 1000g~6000g / t; and the pretreatment time is 6~24h.

[0008] Preferably, the wiping time is 2 to 10 minutes.

[0009] Preferably, after obtaining the undersize material from the dewatering screen, the method further includes: settling the undersize material to obtain a settling overflow and a settling underflow; and using the settling overflow as circulating water and the pretreated ore to make a slurry.

[0010] Preferably, after obtaining the material from the coarse screening, the method further includes: subjecting the material from the coarse screening to magnetic separation to obtain titanium concentrate and first tailings; the magnetic field strength of the magnetic separation is 1~1.5T, the rotation speed is 6~15r / min, and the number of separations is 2~4 times.

[0011] Preferably, the diameter of the first-stage spiral chute is 1.25m, the pitch is 0.65m, and there are 5 spiral turns; The stroke of the first-stage fine sand shaking table and the second-stage fine sand shaking table are independently 13~18mm, and the stroke rate is independently 280~320 times / min.

[0012] Preferably, after obtaining the first tailings and the second tailings, the method further includes: merging the first tailings and the second tailings and then entering them into a second-stage spiral sluice for separation to obtain second-stage spiral sluice concentrate, second-stage spiral sluice middlings, and second tailings; the second-stage spiral sluice has a diameter of 1.25m, a pitch of 0.65m, and 5 spiral coils; The second-stage spiral sluice concentrate is returned to the first-stage fine sand shaking table feed; the ore in the second-stage spiral sluice enters the first-stage slime shaking table for separation, obtaining the first-stage slime shaking table concentrate and the fifth tailings; the first-stage slime shaking table concentrate is returned to the second-stage fine sand shaking table feed, and the fifth tailings are returned to the first-stage slime shaking table separation feed; the stroke of the first-stage slime shaking table is 8~13mm, and the stroke rate is independently 300~350 times / min.

[0013] Preferably, the water content of the zircon rough concentrate and rutile rough concentrate obtained after dehydration is independently 3-12%; the flow rate of the oxygen-containing gas is 0.5-1.5 L / min; the activation time of the oxygen-controlled thermal activation is 30-90 s; the microwave power is 80-150 KW; and the microwave frequency is 2000-2500 MHz.

[0014] Preferably, when the first and second strong magnetic separation tailings are subjected to drum electrostatic separation, arc plate electrostatic separation, and screen plate electrostatic separation respectively; the number of separations in the drum electrostatic separation is independently 3 to 8 times, and the voltage of the drum electrostatic separation is independently 15 to 40 kV; the number of separations in the arc plate electrostatic separation is independently 4 to 6 times, and the voltage of the arc plate electrostatic separation is independently 20 to 30 kV; the number of separations in the screen plate electrostatic separation is independently 2 to 4 times, and the voltage of the screen plate electrostatic separation is independently 20 to 30 kV; the feed temperature of the first and second strong magnetic separation tailings is independently 50 to 90°C.

[0015] Preferably, when the monazite rough concentrate is subjected to drum electrostatic separation and screen electrostatic separation, the drum electrostatic separation operation is performed 2 to 4 times, the voltage of the drum electrostatic separation operation is 20 to 40 kV, the screen electrostatic separation operation is performed 2 to 4 times, the voltage of the screen electrostatic separation operation is 20 to 40 kV, and the feed temperature of the monazite rough concentrate is 50 to 90°C.

[0016] The enhanced separation and purification method for titanium sand ore provided by this invention has the following beneficial effects: (1) Through the full reaction between the cleaning agent and the surface of the target mineral, and with the help of the mechanical force of the scrubbing equipment and the friction between the particles, the fine particles or iron oxide layer covering the surface of the target mineral are removed, thereby restoring the physical and chemical properties of the target mineral itself and enhancing the subsequent electrostatic separation and purification effect. (2) By efficient desliming and priority separation of coarse particles, the number of fine conductor particles that enter the non-conductor product due to excessive charge and insufficient charge transfer in the drum electrostatic separation is reduced. This avoids the number of coarse non-conductor particles that enter the conductor product due to inertial force being greater than electrostatic attraction in the drum electrostatic separation. It also eliminates the disadvantage that coarse conductor particles cannot overcome gravity in the arc plate or sieve plate and directly enter the non-conductor, thus enhancing the electrostatic purification effect. (3) Through the organic combination of equipment and optimized design of process structure, wet separation operation can achieve deep separation and removal of gangue minerals while obtaining zircon rough concentrate and rutile rough concentrate. This reduces the amount of ore fed into the dewatering-drying-electrostatic separation process, improves production efficiency, and saves energy. On the other hand, since gangue minerals do not enter the subsequent operation, the tailings of the zircon electrostatic separation system and the rutile electrostatic separation system are alternately fed into the corresponding dry separation operation instead of returning to the original wet separation system. This eliminates the need for alternating wet and dry separation and repeated dewatering and drying, and achieves low-carbon separation of titanium sand ore. (4) Before electro-separation, the zircon rough concentrate and rutile rough concentrate are subjected to controlled oxygen thermal activation. On the one hand, the weakly magnetic ilmenite is selectively converted into strongly magnetic ilmenite, which expands the magnetic separation range with monazite and iron-bearing rutile. On the other hand, the poorly conductive particles such as leucoxene, anatase, and brookite undergo mineral phase transformation and are converted into particles with good conductivity, which expands the electro-separation zone with non-conductors such as zircon and strengthens the separation of monazite and the purification effect of titanium zirconium minerals.

[0017] In summary, the method provided by this invention can obtain a variety of high-quality zircon concentrate, rutile concentrate, monazite concentrate, iron-bearing rutile concentrate, and titanium concentrate, and can effectively improve system production efficiency and reduce energy consumption. Attached Figure Description

[0018] Figure 1 This is a process flow diagram of the enhanced separation and purification method for titanium sand ore according to the present invention. Detailed Implementation

[0019] This invention provides a method for enhanced separation and purification of titanium sand ore, comprising the following steps: The titanium sand ore is mixed with a cleaning agent solution for pretreatment to obtain pretreated ore. The pretreated raw ore is mixed with water to form a slurry; the slurry is then scrubbed to obtain a scrubbed slurry. The scrubbing slurry is deslimed by passing it through a dewatering screen to obtain the oversize and undersize material. The material on the dewatering screen is subjected to coarse screening to obtain coarse screening oversize and coarse screening undersize; the screen aperture of the coarse screening is ≥0.15mm; The material screened by the coarse screen is fed into the first-stage spiral sluice for separation to obtain the first zircon rough concentrate, the first-stage spiral sluice middlings, and the first tailings; the first-stage spiral sluice middlings are fed into the first-stage fine sand shaking table for separation to obtain the second zircon rough concentrate, the first-stage fine sand shaking table middlings, and the second tailings; the first zircon rough concentrate and the second zircon rough concentrate are combined to obtain the zircon rough concentrate. The zircon rough concentrate and the middlings from the first-stage fine sand shaking table are respectively fed into the second-stage fine sand shaking table for separation. After separation, the zircon rough concentrate yields wet zircon rough concentrate and third tailings. After separation, the middlings from the first-stage fine sand shaking table yields wet gold rough concentrate and fourth tailings. The wet zircon rough concentrate and the wet rutile rough concentrate are dehydrated separately, and then subjected to controlled-oxygen thermal activation in an oxygen-containing gas to obtain dry zircon rough concentrate and dry rutile rough concentrate, respectively; the oxygen-containing gas contains oxygen, and the mass content of oxygen in the oxygen-containing gas is 5-25%. The dry zircon rough concentrate and the dry rutile rough concentrate are respectively subjected to dry weak magnetic separation. After separation, the dry zircon rough concentrate yields a first weak magnetic separation magnetic product and a first weak magnetic separation tailings. After separation, the dry rutile rough concentrate yields a second weak magnetic separation magnetic product and a second weak magnetic separation tailings. The magnetic field strength of the dry weak magnetic separation is ≤0.4T. The tailings from the first and second weak magnetic separations are subjected to dry strong magnetic separation. The tailings from the first weak magnetic separation are separated to obtain monazite rough concentrate and the tailings from the first strong magnetic separation. The tailings from the second weak magnetic separation are separated to obtain the first iron-bearing rutile concentrate and the tailings from the second strong magnetic separation. The magnetic field strength of the dry strong magnetic separation is ≥0.7T. The monazite rough concentrate, the first strong magnetic separation tailings and the second strong magnetic separation tailings are respectively subjected to electrostatic separation; the electrostatic separation system used when the monazite rough concentrate is subjected to electrostatic separation includes drum electrostatic separation and screen plate electrostatic separation in sequence, and the monazite rough concentrate is separated to obtain monazite concentrate and second iron-bearing rutile concentrate. The electrostatic separation systems used for electrostatic separation of the first and second strong magnetic separation tailings respectively include, in sequence, drum electrostatic separation, arc plate electrostatic separation, and screen plate electrostatic separation. Zircon concentrate is obtained after the first strong magnetic separation tailings, and rutile concentrate is obtained after the second strong magnetic separation tailings. The first strong magnetic separation tailings are further processed by the drum electrostatic separation operation to obtain the first electrostatic separation tailings, which are then returned to the second weak magnetic separation tailings for dry strong magnetic separation feeding. The second strong magnetic separation tailings are further processed by the drum electrostatic separation operation to obtain a second electrostatic separation tailings; the second electrostatic separation tailings are returned to the first weak magnetic separation tailings for dry strong magnetic separation feeding.

[0020] In this invention, unless otherwise specified, all raw materials / components used in the preparation are commercially available products well known to those skilled in the art.

[0021] Figure 1 The following is a process flow diagram of the enhanced separation and purification method for titanium sand ore according to the present invention, in conjunction with... Figure 1 The method for enhanced separation and purification of titanium sand provided by the present invention will be described in detail.

[0022] This invention involves pretreating raw titanium sand ore with a cleaning agent solution to obtain pretreated raw ore. Preferably, the raw titanium sand ore comprises the following components by mass: TiO2: 29-35%, ZrO2: 4-8%, Fe: 4.5-8.5%, SiO2: 33-40%, P: 0.1-1.0%; more preferably: TiO2: 30-34%, ZrO2: 5-7%, Fe: 5-8%, SiO2: 35-38%, P: 0.2-0.9%. The main mineral composition of the raw titanium sand ore is preferably leucoxene, anatase, rutile, ilmenite, zircon, quartz, and monazite.

[0023] In a specific embodiment of the present invention, the main chemical element composition (mass content) of the titanium sand ore is as follows: TiO2: 31.44%, ZrO2: 6.61%, Fe: 7.24%, SiO2: 38.23%, P: 0.43%. Alternatively, it may be TiO2: 32.57%, ZrO2: 5.77%, Fe: 6.96%, SiO2: 36.73%, P: 0.52%. Or, it may be TiO2: 34.58%, ZrO2: 7.85%, Fe: 6.43%, SiO2: 34.87%, P: 0.38%.

[0024] The cleaning solution preferably comprises a cleaning agent and water. The cleaning agent preferably comprises one or more of a dibasic organic acid, a ternary organic acid, and an inorganic acid. The inorganic acid is preferably a dibasic inorganic acid. Specifically, the dibasic organic acid is preferably oxalic acid, and the ternary organic acid is preferably citric acid. The inorganic acid is preferably sulfuric acid. More preferably, the cleaning agent is a mixture of a dibasic organic acid and an inorganic acid, or more preferably a mixture of a dibasic organic acid, a ternary organic acid, and an inorganic acid, or a mixture of a dibasic organic acid and a ternary organic acid, or a mixture of a ternary organic acid and an inorganic acid. When the cleaning agent is a mixture of a dibasic organic acid and an inorganic acid, the mass ratio of the dibasic organic acid to the inorganic acid is (0.6~0.9):(0.2~0.4), specifically preferably 0.8:0.2. When the cleaning agent is a mixture of a dibasic organic acid, a ternary organic acid, and an inorganic acid, the mass ratio of the dibasic organic acid, the ternary organic acid, and the inorganic acid is (0.6~0.9):(0.1~0.2):(0.2~0.4). When the cleaning agent is a mixture of a dibasic organic acid and a ternary organic acid, the mass ratio of the dibasic organic acid to the ternary organic acid is (0.6~0.9):(0.1~0.2), preferably 0.9:0.1. When the cleaning agent is a mixture of a ternary organic acid and an inorganic acid, the mass ratio of the ternary organic acid to the inorganic acid is (0.6~0.9):(0.2~0.4), preferably 0.7:0.3. The mass content of the cleaning agent in the cleaning agent solution is preferably 10~40%, preferably 32%, 22%, or 25%. The preferred dosage of the cleaning agent solution is 1000g~6000g / t, specifically 2200g / t, 3400g / t, or 4600g / t. The preferred pretreatment time is 6~24h, specifically 10h, 12h, or 20h. The preferred pretreatment temperature is room temperature.

[0025] The present invention, through the pretreatment, allows the cleaning agent to fully interact with the sludge covering the surface of the target minerals such as titanium and zirconium in the titanium sand ore, resulting in the surface sludge becoming loose, dissolved, or even falling off.

[0026] After obtaining the pretreated raw ore, the present invention mixes the pretreated raw ore with water to form a slurry; the slurry is then scrubbed to obtain a scrubbed slurry. In the present invention, the mass content of the slurry is preferably 55-70%, specifically preferably 65%, 59%, or 68%. The scrubbing is carried out in a scrubbing machine. The scrubbing time is preferably 2-10 minutes, specifically preferably 3.5 minutes, 4 minutes, or 5 minutes. The scrubbing temperature is preferably room temperature. The present invention preferably uses scrubbing, through the combined forces of mechanical force and interparticle friction, to completely remove the mud covering the surface of the target mineral, exposing a fresh surface, thereby restoring its original physicochemical properties.

[0027] After obtaining the scrubbed slurry, the present invention deslims the scrubbed slurry through a dewatering screen to obtain oversize and undersize material. In this invention, the dewatering screen is preferably a vibrating dewatering screen. After obtaining the undersize material, the present invention preferably further includes: settling the undersize material to obtain a settling overflow and a settling underflow; using the settling overflow as a replacement water and the pretreated raw ore to make a slurry, thereby achieving the recycling of water in the settling overflow. The settling underflow is mineral slime; the particle size of the mineral slime is preferably -20 μm.

[0028] After obtaining the oversize material from the dewatering screen, the present invention further performs coarse screening to obtain coarse screening oversize and coarse screening undersize; the screen aperture of the coarse screening is ≥0.15mm. In the present invention, the coarse screening preferably uses a high-frequency vibrating screen. The screen aperture of the coarse screening is preferably 0.15~0.2mm. The coarse screening oversize is coarse sand. The oversize yield is preferably 8~15%. After obtaining the coarse screening oversize, the present invention preferably further includes: performing magnetic separation on the coarse screening oversize to obtain titanium concentrate (hereinafter referred to as first titanium concentrate) and first tailings. The magnetic field strength of the magnetic separation is preferably 1~1.5T, the rotation speed is preferably 6~15r / min, and the number of separations is preferably 2~4 times.

[0029] After obtaining the undersize material from the coarse screening, the present invention feeds the undersize material into a first-stage spiral chute for separation, yielding a first zircon rough concentrate, a first-stage spiral chute middlings, and a first tailings. The first-stage spiral chute middlings are then fed into a first-stage fine sand shaking table for separation, yielding a second zircon rough concentrate, a first-stage fine sand shaking table middlings, and a second tailings. The first and second zircon rough concentrates are combined to obtain a zircon rough concentrate. The zircon rough concentrate and the first-stage fine sand shaking table middlings are then fed into a second-stage fine sand shaking table for separation. The separated zircon rough concentrate yields a wet zircon rough concentrate and a third tailings, while the separated first-stage fine sand shaking table middlings yields a wet rutile rough concentrate and a fourth tailings. In this invention, the diameter (D) of the first-stage spiral chute is preferably 1.25 m, the spiral pitch is preferably 0.65 m, and the spiral coils are preferably 5. The stroke of the first-stage fine sand shaking table is preferably 13-18 mm, specifically 14 mm or 16 mm, and the stroke rate is preferably 280-320 times / min, specifically 315 times / min or 295 times / min. In this invention, the first and second zircon rough concentrates are combined, and the resulting zircon rough concentrate is fed into the second-stage fine sand shaking table A for separation to obtain wet zircon rough concentrate and a third tailings. The third tailings are returned to the second-stage fine sand shaking table A as feed. The stroke of the second-stage fine sand shaking table A is preferably 13-18 mm, specifically 15 mm, 16 mm or 17 mm, and the stroke rate is preferably 280-320 times / min, specifically 318 times / min, 298 times / min or 296 times / min. In this invention, the middlings from the first-stage fine sand shaking table are fed into the second-stage fine sand shaking table B for separation to obtain wet gold-red rough concentrate and a fourth tailings. The fourth tailings are returned to the second-stage fine sand shaking table B as feed. The stroke of the second-stage fine sand shaking table B is preferably 13~18mm, more preferably 16mm or 15mm, and the stroke rate is preferably 280~320 times / min, more preferably 318 times / min, 315 times / min or 316 times / min.

[0030] After obtaining the first and second tailings, the present invention preferably further includes: merging the first and second tailings and then feeding them into a second-stage spiral sluice for separation to obtain a second-stage spiral sluice concentrate, a second-stage spiral sluice middlings, and a second tailings. The second-stage spiral sluice preferably has a diameter of 1.25 m, a pitch of 0.65 m, and 5 spiral coils. The second-stage spiral sluice concentrate is preferably returned to the first-stage fine sand shaking table feed. The second-stage spiral sluice middlings are fed into the first-stage slime shaking table for separation to obtain a first-stage slime shaking table concentrate and a fifth tailings. The first-stage slime shaking table concentrate is preferably returned to the second-stage fine sand shaking table (second-stage fine sand shaking table B) feed for the first-stage fine sand shaking table middlings, and the fifth tailings are returned to the first-stage slime shaking table separation feed. The stroke of the first-stage slime shaking table is preferably 8-13 mm, specifically preferably 12 mm, 10 mm or 8 mm, and the stroke rate is preferably 300-350 times / min, preferably 342 times / min, 348 times / min or 329 times / min.

[0031] This invention yields a wet zircon rough concentrate. The preferred ZrO2 content in the zircon rough concentrate is 51-55%, specifically 53.4%, 51.5%, or 55.0%; the preferred TiO2 content is 4.5-6.5%, specifically 4.7%, 5.2%, or 6.4%. The preferred ZrO2 content in the rutile rough concentrate is 5.5-7.5%, specifically 5.5%, 6.43%, or 7.1%; the preferred TiO2 content is 57.5-60%, specifically 57.6%, 59.32%, or 58.9%.

[0032] After obtaining wet zircon rough concentrate and wet rutile rough concentrate, the present invention dehydrates the wet zircon rough concentrate and the wet rutile rough concentrate separately, and then performs controlled-oxygen thermal activation in an oxygen-containing gas to obtain dry zircon rough concentrate and dry rutile rough concentrate, respectively; the oxygen-containing gas includes oxygen, and the mass content of oxygen in the oxygen-containing gas is 5-25%. In the present invention, the dehydration is preferably carried out through solid-liquid separation. The zircon rough concentrate, rutile rough concentrate, and filtrate obtained after dehydration are used as circulating water and returned to the system. The moisture content of the dehydrated zircon rough concentrate is preferably 3-12%, specifically preferably 5.6%, 6.4%, or 6.8%. The moisture content of the dehydrated rutile rough concentrate is preferably 3-12%, specifically preferably 4.5%, 4.7%, or 3.5%. The controlled-oxygen thermal activation is preferably carried out in a device equipped with a microwave generator. The flow rate of the oxygen-containing gas is preferably 0.5~1.5 L / min, specifically 1.0 L / min, 1.1 L / min, or 1.4 L / min. The oxygen-containing gas includes oxygen, and preferably also includes nitrogen. The mass content of oxygen in the oxygen-containing gas is preferably 5~25%, specifically 15%, 16%, or 14%. The activation time for the oxygen-controlled thermal activation is preferably 30~90 s, specifically 75 s, 50 s, or 55 s. The microwave power is preferably 80~150 KW, specifically 87 KW, 95 KW, or 85 KW. The microwave frequency is preferably 2000~2500 MHz, specifically 2235 MHz, 2210 MHz, or 2390 MHz. In this invention, the steam and material flow direction form a countercurrent in the oxygen-controlled thermal activation equipment, with the material feeding end being the steam outlet end. A temperature gradient is formed in the equipment, simultaneously achieving the dual effects of dehydration and calcination; the steam outlet temperature is preferably 50~120℃.

[0033] After obtaining dry zircon rough concentrate and dry rutile rough concentrate, the present invention further performs dry weak magnetic separation on the two ore concentrates. The dry zircon rough concentrate yields a first weak magnetic separation magnetic product and a first weak magnetic separation tailings, while the dry rutile rough concentrate yields a second weak magnetic separation magnetic product and a second weak magnetic separation tailings. The magnetic field strength of the dry weak magnetic separation is ≤0.4T. In this invention, the magnetic field strength of the dry weak magnetic separation is preferably 0.1~0.4T, specifically preferably 0.2T, 0.34T, or 0.25T. The first and second weak magnetic separation magnetic products are combined to form titanium concentrate (hereinafter referred to as the second titanium concentrate).

[0034] After obtaining the first and second weak magnetic separation tailings, this invention further processes them into dry high-intensity magnetic separation. The first weak magnetic separation tailings, after separation, yield monazite rough concentrate and the first high-intensity magnetic separation tailings. The second weak magnetic separation tailings, after separation, yield the first iron-bearing rutile concentrate and the second high-intensity magnetic separation tailings. The magnetic field strength of the dry high-intensity magnetic separation is ≥0.7T. In this invention, the magnetic field strength of the dry high-intensity magnetic separation is preferably 0.7~1.5T, specifically preferably 1.1T, 1.25T, or 1.2T.

[0035] After obtaining monazite rough concentrate, first strong magnetic separation tailings, and second strong magnetic separation tailings, this invention performs electrostatic separation on the monazite rough concentrate, first strong magnetic separation tailings, and second strong magnetic separation tailings respectively. The electrostatic separation system used for the monazite rough concentrate includes, in sequence, drum electrostatic separation and screen electrostatic separation. After separation, the monazite rough concentrate yields monazite concentrate and second iron-bearing rutile concentrate. The electrostatic separation system used for the first strong magnetic separation tailings and second strong magnetic separation tailings respectively includes, in sequence, drum electrostatic separation. The process includes three stages: electrostatic separation, arc plate electrostatic separation, and screen plate electrostatic separation. The first strong magnetic separation tailings are separated to obtain zircon concentrate, and the second strong magnetic separation tailings are separated to obtain rutile concentrate. The first strong magnetic separation tailings are further processed by the drum electrostatic separation to obtain a first electrostatic separation tailings, which are then returned to the second weak magnetic separation tailings for dry strong magnetic separation. The second strong magnetic separation tailings are further processed by the drum electrostatic separation to obtain a second electrostatic separation tailings, which are then returned to the first weak magnetic separation tailings for dry strong magnetic separation.

[0036] In this invention, the electrostatic separation system used for electrostatic separation of the first and second strong magnetic separation tailings includes, in sequence, drum electrostatic separation, arc plate electrostatic separation, and screen plate electrostatic separation. When electrostatic separation of the first strong magnetic separation tailings: the drum electrostatic separation is preferably performed 3-8 times, specifically 6 or 5 times; the voltage of the drum electrostatic separation is preferably 15-40kV; the voltage of the first drum electrostatic separation is preferably 22kV, 21kV, or 26kV, and the voltage for the remaining separations is increased or decreased by 1kV or 1.1kV depending on the operational requirements. The arc plate electrostatic separation is preferably performed 4-6 times, specifically 4 or 5 times; the voltage of the arc plate electrostatic separation is preferably 20-30kV; the voltage of the first arc plate electrostatic separation is preferably 24kV or 25kV, and the voltage for the remaining separations is increased or decreased by 1kV, 1.1kV, or 1.2kV depending on the operational requirements. The electrostatic precipitator operation is preferably performed 2 to 4 times, specifically 2, 3, or 4 times. The voltage of the electrostatic precipitator operation is preferably 20 to 30 kV. The voltage of the first electrostatic precipitator operation is preferably 25 kV or 24 kV, and the voltage for the remaining operations is increased or decreased by 1 kV, 1.1 kV, or 1.2 kV depending on the operational requirements. The feed temperature of the first strong magnetic separation tailings is preferably 50 to 90°C, specifically 70°C or 79°C. In this invention, the first strong magnetic separation tailings are further processed by the drum electrostatic precipitator to obtain the first electrostatic precipitator tailings, which are then returned to the second weak magnetic separation tailings for dry strong magnetic separation. The tailings from the arc plate electrostatic precipitator operation and the electrostatic precipitator operation are returned to the respective separation operations with similar metal grades within their respective systems.

[0037] When the tailings from the second strong magnetic separation are electrostatically separated: the number of separation operations of the drum electrostatic separation is preferably 3 to 8 times, specifically preferably 5, 7 or 6 times. The voltage of the drum electrostatic separation is preferably 15 to 40 kV. The voltage of the first operation of the drum electrostatic separation is preferably 26 kV or 24 kV. The voltage of the remaining separation operations is increased or decreased by 1.2 kV, 1.0 kV or 1.1 kV according to the operation requirements. The number of separation operations of the arc plate electrostatic separation is preferably 4 to 6 times, specifically preferably 5 or 4 times. The voltage of the arc plate electrostatic separation is preferably 20 to 30 kV. The voltage of the first operation of the arc plate electrostatic separation is preferably 25 kV or 24 kV. The voltage of the remaining separation operations is increased or decreased by 1 kV or 1.2 kV according to the operation requirements. The electrostatic precipitator operation is preferably performed 2 to 4 times, specifically 3 or 4 times; the voltage of the electrostatic precipitator operation is preferably 20 to 30 kV; the voltage of the first electrostatic precipitator operation is preferably 24 kV or 23 kV, and the voltage for subsequent operations is increased or decreased by 1 kV or 1.2 kV depending on the operational requirements. The feed temperature of the second strong magnetic separation tailings is preferably 50 to 90℃, specifically 65℃, 73℃, or 81℃. In this invention, the second strong magnetic separation tailings are further processed by the drum electrostatic precipitator to obtain a second electrostatic precipitator tailings, which is then returned to the dry strong magnetic separation feed for the first weak magnetic separation tailings. The tailings from the arc plate electrostatic precipitator operation and the electrostatic precipitator operation are returned to the respective separation operations with similar metal grades within their respective systems.

[0038] In this invention, the ZrO2 content in the zircon concentrate is preferably 63.0-66.5% and the ZrO2 recovery rate is preferably 85-90%; the TiO2 content in the rutile concentrate is preferably 85.0-92.0% and the TiO2 recovery rate is preferably 60-70%.

[0039] In this invention, the electrostatic separation system used for electrostatic separation of the monazite rough concentrate includes, in sequence, a drum electrostatic separation operation and a screen electrostatic separation operation; the drum electrostatic separation operation preferably performs 2 to 4 separations, specifically 2 or 3 times, and the voltage of the drum electrostatic separation operation is preferably 20 to 40 kV. The voltage of the first separation operation of the drum electrostatic separation is preferably 22 kV or 24 kV, and the voltage for the remaining separations is increased or decreased by 1.2 kV or 1.1 kV according to the operational requirements. The screen electrostatic separation operation preferably performs 2 to 4 separations, specifically 3 or 2 times, and the voltage of the screen electrostatic separation operation is preferably 20 to 40 kV. The voltage of the first separation operation of the screen electrostatic separation is preferably 23 kV or 25 kV, and the voltage for the remaining separations is increased or decreased by 1.2 kV or 1.1 kV according to the operational requirements. The feed temperature of the monazite rough concentrate is preferably 50 to 90°C, specifically 75°C or 81°C. In this invention, when the monazite rough concentrate is subjected to electrostatic separation, the conductive product is the second iron-bearing rutile concentrate, and the non-conductor product is the monazite concentrate.

[0040] In this invention, the TERO content in the monazite concentrate is preferably >60.0 wt%, and the TERO recovery rate is preferably 75-85%.

[0041] In this invention, the first iron-bearing rutile concentrate and the second iron-bearing rutile concentrate are combined to obtain an iron-bearing rutile concentrate. The TiO2 content in the iron-bearing rutile concentrate is preferably 55-70%, and the TiO2 recovery rate is preferably 8-15%. In this invention, the first titanium concentrate and the second titanium concentrate are combined into a single titanium concentrate, wherein the TiO2 content in the titanium concentrate is preferably 47-55% and the TiO2 recovery rate is preferably 6-14%.

[0042] To further illustrate the present invention, the technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0043] Example 1 The leucoxene-type titanium sand ore imported from Australia is a complex and difficult-to-process titanium sand deposit. The main chemical elemental composition of the raw material is: TiO2: 31.44wt%, ZrO2: 6.61wt%, Fe: 7.24wt%, SiO2: 38.23wt%, P: 0.43wt%. The main mineral components are leucoxene, anatase, rutile, ilmenite, zircon, quartz, and monazite. To achieve efficient utilization of this resource, the specific implementation steps are as follows: (1) Pretreatment A mixed solution of oxalic acid and sulfuric acid with a mass concentration of 22% was added to the titanium sand ore raw material. The mass ratio of organic acid to inorganic acid was 0.8:0.2, the addition amount was 2200 g / t, and the reaction time was 10 hours. (2) Scrubbing The pretreated raw ore obtained in step (1) was prepared into a slurry with a concentration of 65%, and then scrubbed in a scrubbing machine for 3.5 min; (3) Desliming The scrubbing slurry obtained in step (2) is transferred to a vibrating dewatering screen for desliming to obtain the oversize and undersize of the dewatering screen. The undersize continues to enter the settling tank to obtain the settling bottom flow as sludge with a particle size of -20μm. The settling supernatant is returned to the separation system for recycling. (4) Coarse sorting The oversize material obtained from the dewatering screen in step (3) is coarsely screened by a high-frequency vibrating screen with a screen aperture size of 0.18 mm to obtain coarsely screened oversize and undersize material, with an oversize yield of 12.4%. The oversize material is then further processed by a plate magnetic separator with a magnetic field strength of 1.2 T, a rotation speed of 7 r / min, and three separation cycles to obtain titanium concentrate I and tailings I. (5) Reselect The material obtained from the coarse screening in step (4) is fed into the first-stage spiral chute for separation. The spiral chute has a diameter of 1.25m, a pitch of 0.65m, and 5 spiral turns to obtain zircon rough concentrate I, middlings and tailings I. The middlings are then fed into the first-stage fine sand shaking table for separation. The shaking table has a stroke of 14mm and a stroke rate of 315 times / min to obtain zircon rough concentrate II, middlings and tailings II. The zircon rough concentrate I and zircon rough concentrate II are combined and fed into the second-stage fine sand shaking table A for separation. The shaking table stroke is 15 mm and the stroke rate is 318 times / min, yielding wet zircon rough concentrate and tailings from the second-stage fine sand shaking table A. The zircon rough concentrate contains ZrO2: 53.4 wt% and TiO2: 4.7 wt%. The tailings are returned to the feed for this operation. The ore from the first-stage fine sand shaking table is then fed into the second-stage fine sand shaking table B for separation. The shaking table stroke is 16 mm and the stroke rate is 315 times / min, yielding wet rutile rough concentrate and tailings from the second-stage fine sand shaking table B. The rutile rough concentrate contains... TiO2: 57.6wt%, ZrO2: 5.5wt%, tailings are returned to the feed for this operation; tailings I and tailings II are combined and fed into the second-stage spiral sluice for separation. The spiral sluice has a diameter of 0.9m, a pitch of 0.45m, and 4 spiral turns, yielding second-stage spiral sluice concentrate, middlings, and tailings II. The concentrate is returned to the first-stage fine sand shaking table feed, while the middlings are fed into the first-stage slime shaking table for separation. The shaking table has a stroke of 12mm and a stroke rate of 342 times / min, yielding first-stage slime shaking table concentrate and tailings. The concentrate is returned to the second-stage fine sand shaking table B feed, while the tailings are returned to the feed for this operation.

[0044] (6) Dehydration The obtained wet zircon rough concentrate and wet rutile rough concentrate were subjected to solid-liquid separation to obtain dehydrated zircon rough concentrate, rutile rough concentrate and filtrate. The zircon rough concentrate contained 5.6% water and the rutile rough concentrate contained 4.5% water. The filtrate was returned to the system as circulating water.

[0045] (7) Oxygen-controlled thermal activation The dehydrated zircon rough concentrate and rutile rough concentrate were thermally activated separately in a device equipped with a microwave generator, while a 1.1 L / min oxygen-nitrogen mixed gas containing 14% oxygen was introduced. The activation time was 55 s, the microwave power was 85 KW, and the microwave frequency was 2390 MHz, to obtain dry zircon rough concentrate and rutile rough concentrate.

[0046] (8) Magnetic separation The obtained dry zircon rough concentrate and rutile rough concentrate were respectively fed into dry weak magnetic separation operations I and II for magnetic separation, with a magnetic field strength of 0.2T in both cases. Both yielded weak magnetic separation magnetic products and tailings. The two magnetic products were combined to form titanium concentrate II. The tailings from dry weak magnetic separation operations I and II were then fed into dry strong magnetic separation operations I and II for magnetic separation, with a magnetic field strength of 1.1T in both cases. This yielded four products: dry strong magnetic separation operation I concentrate (monazite rough concentrate), dry strong magnetic separation operation I tailings, dry strong magnetic separation operation II concentrate (iron-bearing rutile concentrate I), and dry strong magnetic separation operation II tailings.

[0047] (9) Electrostatic purification The tailings from the dry high-intensity magnetic separation operation I are sequentially fed into electrostatic separation system I, which consists of drum electrostatic separation operation A, arc plate electrostatic separation operation A, and screen plate electrostatic separation operation A. The feed heating temperature is 65℃. Drum electrostatic separation operation A is performed 6 times, with the first separation voltage at 22kV. The voltage is increased or decreased by 1 kV for each subsequent separation, depending on the operational requirements. The tailings are then returned to the dry high-intensity magnetic separation operation II. Arc plate electrostatic separation operation A and screen plate electrostatic separation operation A are performed 4 times and 2 times, respectively, with the first separation voltage at 24kV and 25kV, respectively. The voltage is increased or decreased by 1 kV for each subsequent separation, depending on the operational requirements. The middlings from the arc plate electrostatic separation operation and the screen plate electrostatic separation operation are returned to the separation position with the closest ZrO2 grade in their respective separation operations, ultimately obtaining zircon concentrate with ZrO2: 65.4wt% and a recovery rate of 89.55%.

[0048] The tailings from the dry high-intensity magnetic separation operation II are sequentially fed into electrostatic separation system II, which consists of drum electrostatic separation operation B, arc plate electrostatic separation operation B, and screen plate electrostatic separation operation B. The feed heating temperature is 70℃. Drum electrostatic separation operation B performs 5 separations, with the first separation voltage at 26kV. The voltage for the remaining separations is increased or decreased by 1.2 kV according to the operational requirements. The tailings are then returned to the dry high-intensity magnetic separation operation I. Arc plate electrostatic separation operation B and screen plate electrostatic separation operation B perform 5 and 3 separations, respectively, with the first separation voltages at 25kV and 24kV, respectively. The voltage for the remaining separations is increased or decreased by 1.0 kV according to the operational requirements. The middlings from arc plate electrostatic separation operation B and screen plate electrostatic separation operation B are returned to the separation position with a similar TiO2 grade in their respective separation operations, ultimately obtaining a gold-red concentrate with TiO2: 90.1wt% and a recovery rate of 68%.

[0049] The monazite rough concentrate obtained in step (8) is sequentially fed into electrostatic separation system III, which consists of drum electrostatic separation operation C and screen plate electrostatic separation operation C. The feed heating temperature is 75℃. The drum electrostatic separation operation C is performed twice, with the voltage of the first separation being 22kV. The voltage of the remaining separations is increased or decreased by 1.0 kV according to the operation requirements. The screen plate electrostatic separation operation C is performed three times, with the voltage of the first separation being 23kV. The voltage of the remaining separations is increased or decreased by 1.2kV according to the operation requirements. Finally, monazite concentrate and iron-bearing rutile concentrate II are obtained. The monazite concentrate has a TERO content of 62.5wt% and a recovery rate of 81.3%.

[0050] In the above process, titanium concentrate I and titanium concentrate II are combined into titanium concentrate, of which TiO2: 51.2wt% and TiO2 recovery rate is 9.5%; iron-bearing rutile concentrate I and iron-bearing rutile concentrate II are combined into iron-bearing rutile concentrate, of which TiO2: 63.5wt% and TiO2 recovery rate is 10.5%.

[0051] Example 2: The altered titanium deposit in a certain region of China is a complex and difficult-to-process titanium sand deposit. The main chemical elemental composition of the raw material is: TiO2: 32.57wt%, ZrO2: 5.77wt%, Fe: 6.96wt%, SiO2: 36.73wt%, P: 0.52wt%. The main mineral composition is leucoxene, iron-bearing rutile, rutile, ilmenite, zircon, quartz, and monazite. To achieve efficient utilization of this resource, the specific implementation steps are as follows: (1) Pretreatment A mixed solution of a dibasic organic acid and a tribasic organic acid with a mass concentration of 25% was added to the altered titanium sand ore raw material. The mass ratio of oxalic acid to citric acid was 0.9:0.1, the addition amount was 3400 g / t, and the reaction time was 12 hours. (2) Scrubbing The pretreated raw ore obtained in step (1) was prepared into a slurry with a concentration of 59%, and then scrubbed in a scrubbing machine for 4.0 min; (3) Desliming The scrubbing slurry obtained in step (2) is transferred to a vibrating dewatering screen for desliming to obtain the oversize and undersize of the dewatering screen. The undersize continues to enter the settling tank to obtain the settling bottom flow as sludge with a particle size of -18μm. The settling supernatant is returned to the separation system for recycling. (4) Coarse sorting The oversize material obtained from the dewatering screen in step (3) is coarsely screened by a high-frequency vibrating screen with a screen aperture size of 0.16 mm to obtain coarsely screened oversize and undersize material, with an oversize yield of 13.5%. The oversize material is then further processed by a plate magnetic separator with a magnetic field strength of 1.3 T, a rotation speed of 9 r / min, and two separation cycles to obtain titanium concentrate I and tailings I. (5) Reselect The material obtained from the coarse screening in step (4) is fed into the first-stage spiral chute for separation. The spiral chute has a diameter of 1.25m, a pitch of 0.65m, and 5 spiral turns, yielding zircon rough concentrate I, middlings and tailings I. The middlings are then fed into the first-stage fine sand shaking table for separation. The shaking table has a stroke of 16mm and a stroke rate of 295 times / min, yielding zircon rough concentrate II, middlings and tailings II. The zircon rough concentrate I and zircon rough concentrate II are combined and fed into the second-stage fine sand shaking table A for separation. The shaking table stroke is 17 mm and the stroke rate is 298 times / min, yielding wet zircon rough concentrate and tailings from the second-stage fine sand shaking table A. The zircon rough concentrate contains ZrO2: 51.1 wt% and TiO2: 6.4% wt%. The tailings are returned to the feed for this operation. The ore from the first-stage fine sand shaking table is then fed into the second-stage fine sand shaking table B for separation. The shaking table stroke is 16 mm and the stroke rate is 316 times / min, yielding wet rutile rough concentrate and tailings from the second-stage fine sand shaking table B. The rutile rough concentrate contains T... iO2: 59.32wt%, ZrO2: 6.43wt%, tailings are returned to the feed for this operation; tailings I and tailings II are combined and fed into the second-stage spiral sluice for separation. The spiral sluice has a diameter of 0.9m, a pitch of 0.45mm, and 4 spiral turns, yielding second-stage spiral sluice concentrate, middlings, and tailings II. The concentrate is returned to the first-stage fine sand shaking table feed, while the middlings are fed into the first-stage slime shaking table for separation. The shaking table has a stroke of 10mm and a stroke rate of 348 times / min, yielding first-stage slime shaking table concentrate and tailings. The concentrate is returned to the second-stage fine sand shaking table B feed, while the tailings are returned to the feed for this operation.

[0052] (6) Dehydration The obtained wet zircon rough concentrate and wet rutile rough concentrate were subjected to solid-liquid separation to obtain dehydrated zircon rough concentrate, rutile rough concentrate and filtrate. The zircon rough concentrate contained 6.4% water and the rutile rough concentrate contained 4.7% water. The filtrate was returned to the system as circulating water.

[0053] (7) Oxygen-controlled thermal activation The dehydrated zircon rough concentrate and rutile rough concentrate were thermally activated separately in a device equipped with a microwave generator, while a 1.4 L / min oxygen-nitrogen mixed gas containing 16% oxygen was introduced. The activation time was 50 s, the microwave power was fixed at 95 KW, and the microwave frequency was 2210 MHz, to obtain dry zircon rough concentrate and rutile rough concentrate.

[0054] (8) Magnetic separation The obtained dry zircon rough concentrate and rutile rough concentrate were respectively fed into dry weak magnetic separation operations I and II for magnetic separation, with a magnetic field strength of 0.34T in both cases. Both yielded weak magnetic separation magnetic products and tailings. The two magnetic products were combined to form titanium concentrate II. The tailings from dry weak magnetic separation operations I and II were then fed into dry strong magnetic separation operations I and II for magnetic separation, with a magnetic field strength of 1.25T in both cases. This yielded four products: dry strong magnetic separation operation I concentrate (monazite rough concentrate), dry strong magnetic separation operation I tailings, dry strong magnetic separation operation II concentrate (iron-bearing rutile concentrate I), and dry strong magnetic separation operation II tailings.

[0055] (9) Electrostatic purification The tailings from the dry high-intensity magnetic separation operation I are sequentially fed into electrostatic separation system I, which consists of drum electrostatic separation operation A, arc plate electrostatic separation operation A, and screen plate electrostatic separation operation A. The feed heating temperature is 70℃. Drum electrostatic separation operation A is performed 5 times, with the first separation voltage at 21kV. The voltage is increased or decreased by 1 kV for each subsequent separation, depending on the operational requirements. The tailings are then returned to the dry high-intensity magnetic separation operation II. Arc plate electrostatic separation operation A and screen plate electrostatic separation operation A are performed 5 times and 3 times, respectively, with the first separation voltage at 25kV and 24kV, respectively. The voltage is increased or decreased by 1.1 kV for each subsequent separation, depending on the operational requirements. The middlings from the arc plate electrostatic separation operation and the screen plate electrostatic separation operation are returned to the separation position with a similar ZrO2 grade in their respective separation operations, ultimately obtaining zircon concentrate with ZrO2: 66.1wt% and a recovery rate of 87.2%.

[0056] The tailings from the dry high-intensity magnetic separation operation II are sequentially fed into electrostatic separation system II, which consists of drum electrostatic separation operation B, arc plate electrostatic separation operation B, and screen plate electrostatic separation operation B. The feed heating temperature is 73℃. Drum electrostatic separation operation B performs 7 separations, with the first separation voltage at 25kV. The voltage for the remaining separations is increased or decreased by 1.0 kV according to the operational requirements. The tailings are then returned to the dry high-intensity magnetic separation operation I. Arc plate electrostatic separation operation B and screen plate electrostatic separation operation B perform 4 and 3 separations, respectively, with the first separation voltages at 24kV and 23kV, respectively. The voltage for the remaining separations is increased or decreased by 1.0 kV according to the operational requirements. The middlings from arc plate electrostatic separation operation B and screen plate electrostatic separation operation B are returned to the separation position with similar TiO2 grade in their respective separation operations, finally obtaining gold-red concentrate, with TiO2: 90.48wt% and a recovery rate of 66.34%.

[0057] The monazite rough concentrate obtained in step (8) is sequentially fed into electrostatic separation system III, which consists of drum electrostatic separation operation C and screen plate electrostatic separation operation C. The feed heating temperature is 65℃. The drum electrostatic separation operation C is performed twice, with the voltage of the first separation being 22kV. The voltage of the remaining separations is increased or decreased by 1.0 kV according to the operation requirements. The screen plate electrostatic separation operation C is performed three times, with the voltage of the first separation being 24kV. The voltage of the remaining separations is increased or decreased by 1.2 kV according to the operation requirements. Finally, monazite concentrate and iron-bearing rutile concentrate II are obtained. The monazite concentrate has a TERO content of 63.5wt% and a recovery rate of 80.44%.

[0058] In the above process, titanium concentrate I and titanium concentrate II are combined into titanium concentrate, with TiO2 content of 53.5 wt% and TiO2 recovery rate of 7.8%; iron-bearing rutile concentrate I and iron-bearing rutile concentrate II are combined into iron-bearing rutile concentrate, with TiO2 content of 67.2 wt% and TiO2 recovery rate of 12.4%.

[0059] Example 3: The complex and difficult-to-process titanium sand ore imported from Mozambique has the following main chemical element composition: TiO2: 34.58wt%, ZrO2: 7.85wt%, Fe: 6.43wt%, SiO2: 34.87wt%, P: 0.38wt%. Its main mineral components are leucoxene, rutile, iron-bearing rutile, ilmenite, zircon, quartz, and monazite. To achieve efficient utilization of this resource, the specific implementation steps are as follows: (1) Pretreatment A mixed solution of organic tricarboxylic acid and inorganic dicarboxylic acid with a mass concentration of 32% was added to titanium sand ore raw material. The mass ratio of citric acid to sulfuric acid was 0.7:0.3, the addition amount was 4600 g / t, and the reaction time was 20 hours. (2) Scrubbing The pretreated raw ore obtained in step (1) was prepared into a slurry with a concentration of 68%, and then scrubbed in a scrubbing machine for 5 minutes. (3) Desliming The scrubbing slurry obtained in step (2) is transferred to a vibrating dewatering screen for desliming to obtain the oversize and undersize of the dewatering screen. The undersize continues to enter the settling tank to obtain the settling bottom flow as sludge with a particle size of -15μm. The settling supernatant is returned to the separation system for recycling. (4) Coarse sorting The oversize material obtained from the dewatering screen in step (3) is coarsely screened by a high-frequency vibrating screen with a screen aperture size of 0.15 mm to obtain coarsely screened oversize and undersize material, with an oversize yield of 14.6%. The oversize material is then further processed by a plate magnetic separator with a magnetic field strength of 1.4 T, a rotation speed of 12 r / min, and three separations to obtain titanium concentrate I and tailings I. (5) Reselect The material obtained from the coarse screening in step (4) is fed into the first-stage spiral chute for separation. The spiral chute has a diameter of 1.25m, a pitch of 0.65m, and 5 spiral turns, yielding zircon rough concentrate I, middlings and tailings I. The middlings are then fed into the first-stage fine sand shaking table for separation. The shaking table has a stroke of 16mm and a stroke rate of 295 times / min, yielding zircon rough concentrate II, middlings and tailings II. The zircon rough concentrate I and zircon rough concentrate II are combined and fed into the second-stage fine sand shaking table A for separation. The shaking table stroke is 17 mm and the stroke rate is 296 times / min, yielding wet zircon rough concentrate and tailings from the second-stage fine sand shaking table A. The zircon rough concentrate contains ZrO2: 55.0 wt% and TiO2: 5.2 wt%. The tailings are returned to the feed for this operation. The ore from the first-stage fine sand shaking table is then fed into the second-stage fine sand shaking table B for separation. The shaking table stroke is 15 mm and the stroke rate is 318 times / min, yielding wet rutile rough concentrate and tailings from the second-stage fine sand shaking table B. The content of TiO2 is 58.9 wt%, ZrO2 is 7.1 wt%, and the tailings are returned to the feed for this operation. The tailings I and tailings II are combined and fed into the second-stage spiral sluice for separation. The spiral sluice has a diameter of 0.9 m, a pitch of 0.45 m, and 4 spiral turns. The result is the second-stage spiral sluice concentrate, middlings, and tailings II. The concentrate is returned to the first-stage fine sand shaking table feed, and the middlings are fed into the first-stage slime shaking table for separation. The shaking table has a stroke of 8 mm and a stroke rate of 329 times / min. The result is the first-stage slime shaking table concentrate and tailings. The concentrate is returned to the second-stage fine sand shaking table B feed, and the tailings are returned to the feed for this operation.

[0060] (6) Dehydration The obtained wet zircon rough concentrate and wet rutile rough concentrate were subjected to solid-liquid separation to obtain dehydrated zircon rough concentrate, rutile rough concentrate and filtrate, wherein the zircon rough concentrate contained 6.8 wt% water and the rutile rough concentrate contained 3.5 wt% water, and the filtrate was returned to the system as circulating water.

[0061] (7) Oxygen-controlled thermal activation The dehydrated zircon rough concentrate and rutile rough concentrate were thermally activated separately in a device equipped with a microwave generator, while a 1.0 L / min oxygen-nitrogen mixed gas containing 15% oxygen was introduced. The activation time was 75 s, the microwave power was fixed at 87 KW, and the microwave frequency was 2235 MHz, to obtain dry zircon rough concentrate and rutile rough concentrate.

[0062] (8) Magnetic separation The obtained dry zircon rough concentrate and rutile rough concentrate were respectively fed into dry weak magnetic separation operations I and II for magnetic separation, with a magnetic field strength of 0.25T in both cases. Both yielded weak magnetic separation magnetic products and tailings. The two magnetic products were combined to form titanium concentrate II. The tailings from dry weak magnetic separation operations I and II were then fed into dry strong magnetic separation operations I and II for magnetic separation, with a magnetic field strength of 1.2T in both cases. This yielded four products: dry strong magnetic separation operation I concentrate (monazite rough concentrate), dry strong magnetic separation operation I tailings, dry strong magnetic separation operation II concentrate (iron-bearing rutile concentrate I), and dry strong magnetic separation operation II tailings.

[0063] (9) Electrostatic purification The tailings from the dry high-intensity magnetic separation operation I are sequentially fed into electrostatic separation system I, which consists of drum electrostatic separation operation A, arc plate electrostatic separation operation A, and screen plate electrostatic separation operation A. The feed heating temperature is 88℃. Drum electrostatic separation operation A performs 7 separations, with the first separation voltage at 23kV. The voltage for the remaining separations is increased or decreased by 1 kV according to operational requirements. The tailings are then returned to the dry high-intensity magnetic separation operation II. Arc plate electrostatic separation operation A and screen plate electrostatic separation operation A perform 6 and 3 separations, respectively, with the first separation voltages at 28kV and 25kV, respectively. The voltage for the remaining separations is increased or decreased by 1.2 kV according to operational requirements. The middlings from the arc plate electrostatic separation operation and the screen plate electrostatic separation operation are returned to the separation position with similar ZrO2 grade in their respective separation operations, ultimately obtaining zircon concentrate with ZrO2: 66.25wt% and a recovery rate of 85.34%.

[0064] The tailings from the dry high-intensity magnetic separation operation II are sequentially fed into electrostatic separation system II, which consists of drum electrostatic separation operation B, arc plate electrostatic separation operation B, and screen plate electrostatic separation operation B. The feed heating temperature is 79℃. Drum electrostatic separation operation B performs 6 separations, with the first separation voltage at 26kV. The voltage for the remaining separations is increased or decreased by 1.1 kV according to the operational requirements. The tailings are then returned to the dry high-intensity magnetic separation operation I. Arc plate electrostatic separation operation B and screen plate electrostatic separation operation B perform 4 separations, with the first separation voltages at 25kV and 24kV, respectively. The voltage for the remaining separations is increased or decreased by 1.2 kV according to the operational requirements. The middlings from arc plate electrostatic separation operation B and screen plate electrostatic separation operation B are returned to the separation position with similar TiO2 grade in their respective separation operations, finally obtaining gold-red concentrate, with TiO2: 91.03wt% and a recovery rate of 63.57%.

[0065] The monazite rough concentrate obtained in step (8) is sequentially fed into electrostatic separation system III, which consists of drum electrostatic separation operation C and screen plate electrostatic separation operation C. The feed heating temperature is 81℃. The drum electrostatic separation operation C is performed 3 times, with the voltage of the first separation being 24kV. The voltage of the remaining separations is increased or decreased by 1.1 kV according to the operation requirements. The screen plate electrostatic separation operation C is performed 2 times, with the voltage of the first separation being 25kV. The voltage of the remaining separations is increased or decreased by 1.1 kV according to the operation requirements. Finally, monazite concentrate and iron-bearing rutile concentrate II are obtained. The monazite concentrate has a TERO content of 63.7wt% and a recovery rate of 79.5%.

[0066] In the above process, titanium concentrate I and titanium concentrate II are combined into titanium concentrate, of which TiO2: 49.7wt% and TiO2 recovery rate is 13.2%; iron-bearing rutile concentrate I and iron-bearing rutile concentrate II are combined into iron-bearing rutile concentrate, of which TiO2: 60.5wt% and TiO2 recovery rate is 9.9%.

[0067] As can be seen from the above embodiments, the enhanced separation and purification method for titanium sand ore provided by this invention, targeting complex and difficult-to-process titanium sand ore, obtains narrow-particle-size feed material through pretreatment with added cleaning agents, scrubbing under combined forces, and coarse separation, creating favorable conditions for subsequent separation operations. Then, wet gravity separation is performed. Through the synergistic effect of spiral chute and fine sand bed equipment and the optimized design of the gravity separation process structure, wet zircon rough concentrate and rutile rough concentrate are obtained. Simultaneously, deep separation and removal of gangue minerals are achieved, improving the subsequent purification efficiency of the system. The process involves several steps: first, dehydration and controlled-oxygen thermal activation are performed on wet zircon rough concentrate and rutile rough concentrate, respectively. This selectively transforms ilmenite into strongly magnetic ilmenite minerals and causes phase transformation in poorly conductive particles such as leucoxene, anatase, and brookite, thereby expanding the separation zone between these particles and non-conductive materials like zircon. Finally, the oxygen-controlled thermally activated zircon rough concentrate and rutile rough concentrate are subjected to weak magnetic-strong magnetic-electrostatic separation to obtain high-quality zircon concentrate, rutile concentrate, monazite concentrate, iron-bearing rutile concentrate, titanium concentrate, and other products. This invention provides a method for enhanced separation and purification of complex and difficult-to-process titanium sand ores. It effectively removes fine-grained capping material from the surface of the target mineral, reduces the amount of gangue minerals fed into the dehydration-drying-electrostatic separation process, integrates a controlled-oxygen thermal activation unit, eliminates alternating wet and dry separation and repeated dehydration and drying, and improves system production efficiency while saving energy.

[0068] Although the above embodiments have provided a detailed description of the present invention, they are only some embodiments of the present invention, and not all embodiments. Other embodiments can be obtained based on these embodiments without creative effort, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A method for enhanced separation and purification of titanium sand ore, characterized in that, Includes the following steps: The titanium sand ore is mixed with a cleaning agent solution for pretreatment to obtain pretreated ore. The pretreated raw ore is mixed with water to form a slurry; The slurry is scrubbed to obtain scrubbed slurry; The scrubbing slurry is deslimed by passing it through a dewatering screen to obtain the oversize and undersize material. The material on the dewatering screen is subjected to coarse screening to obtain coarse screening oversize and coarse screening undersize; the screen aperture of the coarse screening is ≥0.15mm; The material screened by the coarse screen is fed into the first-stage spiral sluice for separation to obtain the first zircon rough concentrate, the first-stage spiral sluice middlings, and the first tailings; the first-stage spiral sluice middlings are fed into the first-stage fine sand shaking table for separation to obtain the second zircon rough concentrate, the first-stage fine sand shaking table middlings, and the second tailings; the first zircon rough concentrate and the second zircon rough concentrate are combined to obtain the zircon rough concentrate. The zircon rough concentrate and the middlings from the first-stage fine sand shaking table are respectively fed into the second-stage fine sand shaking table for separation. After separation, the zircon rough concentrate yields wet zircon rough concentrate and third tailings. After separation, the middlings from the first-stage fine sand shaking table yields wet gold rough concentrate and fourth tailings. The wet zircon rough concentrate and the wet rutile rough concentrate are dehydrated and then subjected to controlled-oxygen thermal activation in oxygen-containing gas to obtain dry zircon rough concentrate and dry rutile rough concentrate, respectively; the oxygen-containing gas contains oxygen, and the mass content of oxygen in the oxygen-containing gas is 5-25%. The dry zircon rough concentrate and the dry rutile rough concentrate are respectively subjected to dry weak magnetic separation. After separation, the dry zircon rough concentrate yields a first weak magnetic separation magnetic product and a first weak magnetic separation tailings. After separation, the dry rutile rough concentrate yields a second weak magnetic separation magnetic product and a second weak magnetic separation tailings. The magnetic field strength of the dry weak magnetic separation is ≤0.4T. The tailings from the first and second weak magnetic separations are subjected to dry strong magnetic separation. The tailings from the first weak magnetic separation are separated to obtain monazite rough concentrate and the tailings from the first strong magnetic separation. The tailings from the second weak magnetic separation are separated to obtain the first iron-bearing rutile concentrate and the tailings from the second strong magnetic separation. The magnetic field strength of the dry strong magnetic separation is ≥0.7T. The monazite rough concentrate, the first strong magnetic separation tailings and the second strong magnetic separation tailings are respectively subjected to electrostatic separation; the electrostatic separation system used when the monazite rough concentrate is subjected to electrostatic separation includes drum electrostatic separation and screen plate electrostatic separation in sequence, and the monazite rough concentrate is separated to obtain monazite concentrate and second iron-bearing rutile concentrate. The electrostatic separation systems used for electrostatic separation of the first and second strong magnetic separation tailings respectively include, in sequence, drum electrostatic separation, arc plate electrostatic separation, and screen plate electrostatic separation. Zircon concentrate is obtained after the first strong magnetic separation tailings, and rutile concentrate is obtained after the second strong magnetic separation tailings. The first strong magnetic separation tailings are further processed by the drum electrostatic separation operation to obtain the first electrostatic separation tailings, which are then returned to the second weak magnetic separation tailings for dry strong magnetic separation feeding. The second strong magnetic separation tailings are further processed by the drum electrostatic separation operation to obtain a second electrostatic separation tailings; the second electrostatic separation tailings are returned to the first weak magnetic separation tailings for dry strong magnetic separation feeding.

2. The method for enhanced separation and purification of titanium sand ore according to claim 1, characterized in that, The titanium sand ore comprises the following components by mass: TiO2: 29-35%, ZrO2: 4-8%, Fe: 4.5-8.5%, SiO2: 33-40%, P: 0.1-1.0%; the cleaning agent solution comprises a cleaning agent and water, wherein the cleaning agent comprises one or more of a dibasic organic acid, a ternary organic acid, and an inorganic acid; the cleaning agent content in the cleaning agent solution is 10-40% by mass; the amount of the cleaning agent solution used is 1000g-6000g / t; and the pretreatment time is 6-24h.

3. The method for enhanced separation and purification of titanium sand ore according to claim 1, characterized in that, The wiping time is 2 to 10 minutes.

4. The method for enhanced separation and purification of titanium sand ore according to claim 1, characterized in that, After obtaining the undersize material from the dewatering screen, the process further includes: settling the undersize material to obtain a settling overflow and a settling underflow; and using the settling overflow as circulating water and the pretreated raw ore to make a slurry.

5. The method for enhanced separation and purification of titanium sand ore according to claim 1, characterized in that, After obtaining the material from the coarse screening, the process further includes: subjecting the material from the coarse screening to magnetic separation to obtain titanium concentrate and first tailings; the magnetic field strength of the magnetic separation is 1-1.5T, the rotation speed is 6-15r / min, and the number of separations is 2-4 times.

6. The method for enhanced separation and purification of titanium sand ore according to claim 1, characterized in that, The first-stage spiral chute has a diameter of 1.25m, a pitch of 0.65m, and 5 spiral turns; The stroke of the first-stage fine sand shaking table and the second-stage fine sand shaking table are independently 13-18 mm, and the stroke rate is independently 280-320 times / min.

7. The method for enhanced separation and purification of titanium sand ore according to claim 1, characterized in that, After obtaining the first and second tailings, the process further includes: combining the first and second tailings and then separating them in a second-stage spiral sluice to obtain second-stage spiral sluice concentrate, second-stage spiral sluice middlings, and second tailings; the second-stage spiral sluice has a diameter of 1.25m, a pitch of 0.65m, and 5 spiral coils; The second-stage spiral sluice concentrate is returned to the first-stage fine sand shaking table feed; the ore in the second-stage spiral sluice enters the first-stage slime shaking table for separation, obtaining the first-stage slime shaking table concentrate and the fifth tailings; the first-stage slime shaking table concentrate is returned to the second-stage fine sand shaking table feed of the ore in the first-stage fine sand shaking table, and the fifth tailings are returned to the first-stage slime shaking table separation feed; the stroke of the first-stage slime shaking table is 8-13 mm, and the stroke rate is independently 300-350 times / min.

8. The method for enhanced separation and purification of titanium sand ore according to claim 1, characterized in that, The water content of the zircon rough concentrate and rutile rough concentrate obtained after dehydration is independently 3-12%; the flow rate of the oxygen-containing gas is 0.5-1.5 L / min; the activation time of the oxygen-controlled thermal activation is 30-90 s; the microwave power is 80-150 KW; and the microwave frequency is 2000-2500 MHz.

9. The method for enhanced separation and purification of titanium sand ore according to claim 1, characterized in that, When the first and second strong magnetic separation tailings are subjected to drum electrostatic separation, arc plate electrostatic separation, and screen plate electrostatic separation respectively; the number of separations in the drum electrostatic separation is independently 3 to 8 times, and the voltage of the drum electrostatic separation is independently 15 to 40 kV; the number of separations in the arc plate electrostatic separation is independently 4 to 6 times, and the voltage of the arc plate electrostatic separation is independently 20 to 30 kV; the number of separations in the screen plate electrostatic separation is independently 2 to 4 times, and the voltage of the screen plate electrostatic separation is independently 20 to 30 kV; the feed temperature of the first and second strong magnetic separation tailings is independently 50 to 90℃.

10. The method for enhanced separation and purification of titanium sand ore according to claim 1, characterized in that, When the monazite rough concentrate is subjected to drum electrostatic separation and screen electrostatic separation, the drum electrostatic separation operation is performed 2 to 4 times, and the voltage of the drum electrostatic separation operation is 20 to 40 kV. The screen electrostatic separation operation is performed 2 to 4 times, and the voltage of the screen electrostatic separation operation is 20 to 40 kV. The feed temperature of the monazite rough concentrate is 50 to 90℃.

Images