A method for separating and recycling charred black slag from titanium dioxide ore produced by the chloride process

Abstract

The present invention discloses a method for separating, recovering and utilizing the coke black slag of chloride process titanium dioxide ore, comprising the following steps: S1. Adding water to the coke black slag of chloride process titanium dioxide ore and stirring to make a slurry; S2. Adding flotation reagents and bubbling with compressed air to the slurry at a feeding rate of 15-20 m<supgt;3< / supgt> / h, and sequentially passing through 4-stage flotation separation to obtain coking foam and bottom product in the cell. The coking foam in the 1st to 4th stages is collected and combined, and after filtration and drying, carbon concentrate is obtained. The bottom product in the 1st to 3rd stages is transported to the next stage of flotation; S3. Separating the ore belt from the bottom product in the 4th stage through 2-stage shaking table to obtain titanium concentrate and iron tailings. The method provided by the present invention is simple and conducive to popularization, is a very clean production process, will not cause pollution to the environment, completely solves the problem of the outlet of the solid waste coke black slag in the chlorination furnace during the production of chloride process titanium dioxide, and moreover, the obtained product can also serve the chloride process titanium dioxide process itself, realizing the maximum utilization of energy.

Description

Technical Field

[0001] The invention belongs to the technical field of titanium dioxide preparation, and in particular relates to a method for separating and recycling charred black slag of titanium dioxide ore by a chloride process. Background Art

[0002] The chlorination process of titanium dioxide powder by chloride process is to produce titanium tetrachloride (TiCl4) by chlorination reaction of titanium ore such as rutile, high titanium slag (titanium ore grade is measured in TiO2), petroleum coke and liquid chlorine in a chlorination furnace at high temperature. At the same time, impurities in titanium ore such as FeTiO3, FeO, MgO, CaO, Al2O3, SiO2 and the like in oxide form also undergo chlorination reaction. The FeCl3, FeCl2, MgCl2, CaCl2 and high boiling point compounds such as titanium ore and petroleum coke that have not reacted completely are collected from the chlorination furnace cyclone. The dust collection slag varies according to the raw materials. The chlorination furnace will produce 100 to 180 tons of dust collection slag every day for an annual production of 200,000 to 400,000 tons of titanium dioxide powder by chloride process. Its main components are unreacted titanium ore, petroleum coke, FeCl3, FeCl2 and a small amount of metal chlorides such as AlCl3 and MgCl2 produced by chlorination reaction.

[0003] Invention patent CN106311457B discloses a method for extracting titanium from ilmenite leaching residue. The process includes hydrochloric acid pretreatment, calcium oxide neutralization, heavy liquid reverse flotation to remove carbon, and shaking table gravity separation of titanium coarse concentrate, to obtain a carbon grade of more than 35% and a titanium grade of more than 39%. The recovered carbon grade and titanium grade do not meet the material standards for rotary kilns, electric furnaces, and chlorination furnaces, and still need to be purified.

[0004] Invention patent CN114377860A discloses a method for resource utilization of chlorination dust residue of titanium dioxide produced by the chlorination process. The process includes pulping, filtering, pulping, flotation, filtering, pelletizing, drying, and electric furnace smelting, which realizes the resource recovery and utilization of chlorine, carbon, and titanium. However, the flotation agents used include diesel, sodium hydroxy oleate, cotton oil soap, OP-10, starch, and oxalic acid complex, which are of many types and used in large amounts.

[0005] In addition to the lime neutralization method, Chemours, the largest foreign producer of chloride-process titanium dioxide, also slurries the waste slag and injects it into the ground through deep wells, and adds cement, sand and gravel after neutralization to produce building materials. Most domestic companies directly landfill the waste slag or slurry it with industrial water, neutralize and filter it, discharge the sewage, and filter the water-insoluble chloride furnace coke black slag to the slag yard for stacking or landfill. This method is prone to secondary environmental pollution and waste of titanium and petroleum coke resources in the dust slag.

[0006] In view of this, the present invention is proposed in order to separate and recycle the charred black slag of titanium dioxide ore produced by the chloride process. Summary of the invention

[0007] The purpose of the present invention is to provide a method for separating and recycling charred black slag from titanium dioxide ore produced by a chloride process in order to solve the deficiencies of the prior art.

[0008] The purpose of the present invention is achieved by the following technical solutions:

[0009] A method for separating and recycling charred black slag from titanium dioxide ore produced by a chloride process, comprising the following steps:

[0010] S1. Add water to the charred black slag of the chloride titanium dioxide ore and stir to make a slurry, control the stirring liquid level to be 0.3 to 0.5 m higher than the uppermost stirring blade, and obtain a slurry, wherein the mass percentage concentration of the charred black slag in the slurry is 10 to 30%;

[0011] S2. The slurry is heated at 15 to 20 m 3 / h feed rate, adding flotation reagents, and 1.2~1.8m 3 / (m 2 *min) compressed air bubbling, sequentially through 4 stages of flotation separation, each stage of flotation respectively obtains coking foam and tank bottom, the coking foam from stages 1 to 4 is collected and combined, filtered and dried to obtain carbon concentrate, and the tank bottom from stages 1 to 3 is transported to the next stage of flotation;

[0012] The flotation agent in the first stage of flotation is a frother, and the flow rate of the frother is 0.25-0.50 kg / h;

[0013] The flotation reagents in the 2nd to 4th stage flotation are frothers and collectors; the flow rates of the frothers in the 2nd to 4th stage flotation are: 0.25-0.50kg / h, 0.50-1.00kg / h, 0.25-0.50kg / h; the flow rates of the collectors in the 2nd to 4th stage flotation are: 1.10-1.70kg / h, 1.10-1.70kg / h, 0.80-1.30kg / h;

[0014] S3. The trough bottom of the 4th section is passed through a 2-stage shaking table for ore belt separation, wherein the shaking table has a stroke of 8 to 20 mm, a stroke frequency of 250 to 360 times / min, and the parameter settings of the 1st and 2nd stage shaking tables are kept consistent; wherein the roughing tailings of the 1st stage shaking table are passed through a 2nd stage shaking table scavenging selection, the roughing concentrate of the 1st stage shaking table and the scavenging concentrate of the 2nd stage shaking table are combined, filtered and dried to obtain titanium concentrate, and the scavenging tailings of the 2nd stage shaking table are filtered and dried to obtain iron tailings.

[0015] Preferably, the stirring in step S1 adopts double-layer blade stirring, wherein when the height of the first layer of stirring blades is 0.54m and the height of the second layer of stirring blades is 1.54m, the stirring liquid level is controlled to be 1.8-2.0m.

[0016] Preferably, the stirring speed in step S1 is not less than 90 r / min, and the stirring time is not less than 10 min.

[0017] Preferably, the gauge pressure of the compressed air in step S2 is 20-50 kPa.

[0018] Preferably, the foaming agent in step S2 is turpentine; and the collecting agent is light diesel.

[0019] Preferably, the titanium content in the coal-fired slag in step S1 is 15-30% in terms of titanium dioxide, and the carbon content is 20-40% in terms of carbon element.

[0020] Preferably, the carbon content of the carbon concentrate in step S2 is not less than 50% in terms of carbon element; the carbon concentrate is recycled to the chlorination furnace to produce titanium tetrachloride instead of part of the petroleum coke.

[0021] Preferably, the titanium content in the titanium concentrate in step S3 is not less than 60% in terms of titanium dioxide; the titanium concentrate is recycled to a rotary kiln or an electric furnace for smelting to produce titanium chloride slag for use in a chlorination furnace to produce titanium tetrachloride.

[0022] Preferably, each stage of flotation in step S2 is carried out by two flotation machines connected in series.

[0023] Preferably, the filtration in steps S2 and S3 is performed using a filter press, and the filter press pressure is 0.5-1.3 MPa.

[0024] The method provided by the present invention is simple and easy to promote. It is a very clean production process that will not pollute the environment. It completely solves the problem of the disposal of solid waste charred black slag from the chlorination furnace in the production process of chloride titanium dioxide. Moreover, the obtained slag can be used in the chloride titanium dioxide process by itself, thus realizing maximum energy utilization. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a process flow chart for separation and recycling of coke black slag provided in this application. DETAILED DESCRIPTION

[0026] The method for separating and recycling charred black slag of titanium dioxide ore produced by the chloride process disclosed in the present invention comprises the following steps:

[0027] S1. Add water to the charred black slag of the chloride titanium dioxide ore and stir to make a slurry, control the stirring liquid level to be 0.3 to 0.5 m higher than the uppermost stirring blade, and obtain a slurry, wherein the mass percentage concentration of the charred black slag in the slurry is 10 to 30%;

[0028] S2. Mix the slurry at 15-20m 3 / h feed rate, adding flotation reagents, and 1.2~1.8m 3 / (m 2*min) compressed air bubbling, sequentially through 4 stages of flotation separation, each stage of flotation respectively obtains coking foam and tank bottom, the coking foam from stages 1 to 4 is collected and combined, filtered and dried to obtain carbon concentrate, and the tank bottom from stages 1 to 3 is transported to the next stage of flotation;

[0029] The flotation reagent in the first stage is a frother, and the flow rate of the frother is 0.25-0.50 kg / h;

[0030] The flotation reagents in stages 2 to 4 are frothers and collectors; the flow rates of frothers in stages 2 to 4 are: 0.25-0.50kg / h, 0.50-1.00kg / h, 0.25-0.50kg / h; the flow rates of collectors in stages 2 to 4 are: 1.10-1.70kg / h, 1.10-1.70kg / h, 0.80-1.30kg / h.

[0031] After compressed air is blown into the slurry of coke and black slag, bubbles are generated, which absorb or adsorb the petroleum coke to be separated and enriched in the slurry, forming coking foam, which floats to the surface of the slurry and separates. As the scraper of the flotation machine rises, it is squeezed out of the tank, which not only ensures the scraping amount, but also avoids the scraping of the slurry. The addition of flotation reagents, in which the hydrophobic petroleum coke acts with the collector to help adhere to the bubbles, while the hydrophilic titanium ore particles are retained in the water, which helps to achieve mutual separation.

[0032] The foaming agent can be a heteropolar surfactant, slightly soluble in water, and relatively stable in composition, such as turpentine, eucalyptus oil, camphor oil, cresol acid, higher alcohols, synthetic foaming agents, etc., preferably turpentine, more preferably turpentine alcohol. The collector can be a non-polar hydrocarbon oil, such as kerosene, diesel and modified kerosene, etc., preferably light diesel.

[0033] S3. The trough bottom of the fourth section is passed through two shaking tables to form an ore zone separation, and the position of the receiving plate of the concentrate slurry and the tailings slurry is dynamically adjusted to achieve accurate and real-time separation and receiving of the ore; the shaking table stroke is 8-20 mm, and the stroke frequency is 250-360 times / min; the roughing tailings from the first shaking table are scavenged by the second shaking table, the roughing concentrate from the first shaking table and the scavenging concentrate from the second shaking table are combined to obtain concentrate slurry, and the scavenging tailings from the second shaking table are obtained to obtain tailings slurry, and the concentrate slurry and the tailings slurry are respectively subjected to filter pressing and drying to obtain titanium ore of different grades (i.e., titanium concentrate and iron tailings).

[0034] Generally, the shaking table is composed of three parts: the bed surface, the frame and the transmission mechanism. In addition, it also includes other parts such as the flushing trough, the feed trough, the machine base, etc. The entire bed surface is supported or lifted by the frame, and the frame is equipped with a slope adjustment device. According to the density and particle size of the ore particles, the ore particles on the shaking table surface are subjected to three mutually perpendicular forces: the gravity of the ore particles in the medium, the fluid dynamics of the lateral water flow and the slurry flow, and the dynamics of the differential reciprocating motion of the bed surface. The particles move in different directions, and start from the feed trough along the diagonal fan-shaped, and are discharged along the edge of the bed surface in turn. The discharge line is very long, and different grades of titanium ore can be accurately sorted out, such as concentrate, sub-concentrate, medium concentrate and tailings. The trough bottom containing titanium materials is separated by the vibration of the shaking table to obtain titanium concentrate and iron tailings.

[0035] In the present application, the charcoal black slag is first pulped to prepare for flotation. The control of the stirring level and concentration during the pulping process is critical, especially the stirring level. If the stirring level is too low, it is easy to cause insufficient stirring, and the charcoal black slag cannot be fully dispersed, affecting the subsequent separation effect.

[0036] After the slurry is made, it is firstly floated to recover the carbon concentrate, and then it is selected by a shaking table to recover the titanium concentrate. Specifically, the flotation adopts multi-stage flotation, controls the feed amount and the compressed air intake, ensures the stability of the flotation liquid level, and controls the type and amount of flotation reagents added in each stage. In the first stage of flotation, only the frother is added, and the collector is added after the second stage. The amount of frother added in the third stage of flotation is the largest, and the amount of collector added in the fourth stage of flotation is reduced. That is, first stir and foam in the first stage, and then adjust the amount of frother and collector added and the depth of scraping foam in the second to fourth stages according to the density of foam, the material condition, and the thickness of the foam layer. The less carbon is selected, the less reagent is added, which has the effect of improving the carbon yield by one rough and three sweeps. The coking foam after each flotation stage contains a lot of carbon. After the coking foams of each stage are combined and collected, and then filtered, a carbon concentrate with a carbon grade of not less than 50% can be obtained. Although the carbon concentrate does not meet the procurement standard of petroleum coke raw materials, it can be blended with petroleum coke and used in the coking bed of a chlorination furnace to achieve resource recycling.

[0037] After 4 stages of flotation, the bottom of the tank has been subjected to multiple stages of flotation, and most of the carbon has been separated and removed, but it still contains a certain amount of impurities such as carbon, iron, and calcium. Therefore, a 2-stage shaking table is used to separate titanium concentrate and iron tailings by utilizing the difference in density between titanium and other materials. Among them, the stroke and number of strokes of the shaking table have an important influence on the separation effect. For the charred black slag, generally, the material with a particle size of less than 45μm (325 mesh) accounts for more than 90%. Since the particles are slightly smaller, it is preferred to use a small stroke and a large number of strokes. The specific stroke is 8-20mm and the number of strokes is 250-360 times / min, and it is further preferred that the stroke is 15-16mm and the number of strokes is 250 times / min. After the first stage of shaking, the tailings are transported to the second stage of shaking for further separation to improve the concentrate yield. The titanium concentrates from the second stage of shaking are combined and filtered to obtain titanium concentrates with a grade of not less than 60%. The titanium dioxide content in the tailings from the second stage of shaking is 10-30%. In addition to titanium, it also contains a lot of impurities such as iron, carbon, and silicon. The titanium concentrate not only has a high titanium grade, but also has strong applicability. It can be used for electric furnace smelting to generate high-titanium slag, rotary kiln reduction to titanium liquid reduction titanium, chlorination furnace chlorination to generate titanium tetrachloride, etc., and the wastewater from the regeneration filter press can be returned to the ore coke black slag pulping system, without wastewater and waste gas emissions. According to the different grades of titanium ore, it selectively enters the rotary kiln or electric furnace or both to improve the titanium grade. For example, titanium concentrate with higher iron content and 35-50% imported raw materials selectively enter the rotary kiln to be reduced into titanium liquid to reduce titanium; titanium concentrate with less than 85% is mixed with 50-60% imported raw materials and enters the electric furnace to smelt into titanium-rich material; titanium concentrate with more than 85% is directly used in the chlorination furnace to make ore deposits, or both are used together, and finally a chlorination reaction is carried out in the chlorination furnace to generate titanium tetrachloride and coal black slag.

[0038] The method provided by the present invention is simple and easy to promote. It is a very clean production process that will not pollute the environment. It completely solves the problem of the disposal of solid waste charred black slag from the chlorination furnace in the production process of chloride titanium dioxide. Moreover, the obtained slag can be used in the chloride titanium dioxide process by itself, thus realizing maximum energy utilization.

[0039] Preferably, the stirring in step S1 is performed using double-layer blades, wherein when the height of the first layer of blades is 0.54 m and the height of the second layer of blades is 1.54 m, the stirring liquid level is controlled to be 1.8-2.0 m.

[0040] Preferably, the stirring speed in step S1 is not less than 90 r / min, and the stirring time is not less than 10 min, so that the coal coke black slag is fully stirred and dispersed.

[0041] Preferably, the gauge pressure of the compressed air in step S2 is 20-50 kPa.

[0042] During the flotation process, the scraping depth needs to be adjusted and controlled according to the foam layer conditions to squeeze the coking foam out of the tank, which not only ensures the scraping amount but also avoids the scraping of slurry.

[0043] Preferably, the titanium content in the coal-fired slag in step S1 is 15-30% in terms of titanium dioxide, and the carbon content is 20-40% in terms of carbon element.

[0044] Preferably, the carbon content in the carbon concentrate in step S2 is not less than 50% in terms of carbon element; the carbon concentrate replaces part of the petroleum coke and is recycled to the chlorination furnace to produce titanium tetrachloride.

[0045] Preferably, in step S3, the titanium content in the titanium concentrate is not less than 60% in terms of titanium dioxide; the titanium concentrate is recycled to a rotary kiln or an electric furnace for smelting to produce titanium chloride slag, which is then used in a chlorination furnace to produce titanium tetrachloride.

[0046] Preferably, in step S2, each flotation stage is carried out by two flotation machines connected in series.

[0047] Preferably, filter press equipment is used for filtering in steps S2 and S3, and the filtrate is recycled into the pulping process, thereby realizing wastewater recycling and reuse.

[0048] Preferably, the filter press is a membrane filter press, which is a filter press with an elastic membrane installed between the filter plate and the filter cloth. During use, when the feeding is completed, a high-pressure fluid or gas medium can be injected into the diaphragm plate, and then the entire diaphragm will swell to compress the filter cake, thereby achieving further dehydration of the filter cake, which is usually referred to as squeeze filtration, and the squeeze pressure is not higher than 1.3MPa and ≥0.5MPa.

[0049] Preferably, the dryer can be a convection type, conduction type, radiation type, dielectric type, or other type of dryer. For example, a convection dryer uses a hot drying medium to directly contact the wet carbon concentrate, transfers heat by convection, and takes away the generated steam. An indirect dryer uses conduction to transfer heat from a heat source to the wet material through a metal partition. The generated wet steam can be removed by vacuum suction, a small amount of purge gas, or condensation on the surface of a separately set low-temperature condenser. No drying medium is used, the thermal efficiency is high, and the product is not contaminated. It is often operated under vacuum.

[0050] Example 1

[0051] The method for separating and recycling the charred black slag of titanium dioxide ore by the chloride process provided in this embodiment is as follows: Figure 1 As shown, the specific steps include:

[0052] (1) A batch of 7.5 t / h of charred slag containing 28.3% TiO2 and 31.0% carbon, which was washed and filtered by pressure from a titanium dioxide chlorination furnace by the chloride process, was made into a slurry with a mass concentration of 30% charred slag in a stirring tank, and the stirring tank (the stirring tank had a diameter of 2.5 m and a height of 3.58 m, and had two layers of stirring blades, wherein the height of the first layer of stirring blades was 0.54 m and the height of the second layer of stirring blades was 1.54 m) was controlled to have a liquid level between 1.8 and 2.0 m, and the stirring was carried out at a speed of 93 r / min for 10 min;

[0053] (2) The slurry in step (1) was heated to 15 m 3 The feed flow rate of / h is pumped to the flotation machine through a pipeline pump. The impeller is driven by a V-belt drive of the motor. The impeller rotates at a speed of 210r / min, generating a centrifugal effect to form a negative pressure. On the one hand, 1.5m 3 / (m 2 *min) with a gauge pressure of 20kPa and bubbling with compressed air to mix with the slurry; on the one hand, terpineol is added at a rate of 1 drop / s in flotation machines ① to ② for rough selection; then it enters flotation machines ③ to ④, terpineol is added at a rate of 1 drop / s and light diesel oil is added at a rate of 2 drops / s; then it enters flotation machines ⑤ to ⑥, terpineol is added at a rate of 2 drops / s and light diesel oil is added at a rate of 2 drops / s; then it enters flotation machines ⑦ to ⑧, terpineol is added at a rate of 1 drop / s and light diesel oil is added at a rate of 1.5 drops / s, so that the total flow of terpineol and light diesel oil in the flotation stage is 2.15kg / h and 3.0kg / h, respectively, and the slurry is mixed with the flotation agent and the foam is refined at the same time, so that the petroleum coke is bonded to the foam and floats to the surface of the ore pulp to form coking foam; the gate height is adjusted to control the liquid level so that the coking foam is scraped out by the scraper, and the scraper speed is 16r / min to obtain coking foam and tank bottom;

[0054] (3) The bottom of the slurry tank in step (2) automatically flows onto the shaking table surface, and the ore particles are loosened and layered by the water flow and the vibration of the bed surface in the bed groove; the stroke and stroke frequency of the two-stage shaking table are set the same, with a stroke of 10 mm and a stroke of 300 times / min. The upper light mineral particles are pushed by the larger water flow and move laterally along the bed surface to form tailings slurry, which is discharged from the tailings end; the heavy mineral particles at the bottom of the bed are moved to the opposite side of the transmission end by the vibration of the bed surface, forming concentrate slurry, which is discharged from the concentrate end. The ore particles have different specific gravities and particle sizes, so their movement directions are also different. The ore particles start from the feed trough and fan out along the diagonal line. The position of the receiving plate of the concentrate slurry and the tailing slurry is dynamically adjusted to achieve accurate and real-time separation of the concentrate slurry and the tailing slurry. Both the 1st and 2nd stage shaking tables are composed of a bed surface, a frame, a transmission mechanism, a flushing trough, a feed trough, a machine base, etc. The entire bed surface is supported or lifted by the frame, and a slope adjustment device is installed on the frame. The ore dressing shaking table can make the ore particles move in different directions according to their density and particle size, and spread out in a fan shape along the diagonal starting from the feed trough, and then discharged along the edge of the bed surface in sequence. The discharge line is very long and can accurately produce a variety of products of different qualities, such as concentrates and tailings. The tailings slurry separated by the 1st stage shaking table is further separated in the 2nd stage shaking table, and the resulting concentrate slurry is combined with the concentrate slurry from the 1st stage shaking table, and finally the concentrate slurry and tailings slurry are produced;

[0055] (4) The coking foam in step (2), the concentrate slurry and the tailings slurry in step (4) are stored in respective storage tanks, and after reaching a certain liquid level, they enter the diaphragm filter presses for the coking foam, the concentrate slurry and the tailings slurry respectively; when the feeding is completed, a 0.5 MPa high-pressure fluid is injected into the diaphragm plate of each filter press to make the diaphragm bulge and compress the filter cake to dehydrate, and all the filtrate is recovered into the pulping tank, thereby realizing the recycling and reuse of process wastewater and saving costs;

[0056] (5) The filter cakes discharged from the membrane filter press of the coking foam, concentrate slurry and tailing slurry in step (4) are dried in a convection or conduction dryer to obtain a carbon concentrate with 61.3% fixed carbon, a titanium concentrate with 81.9% TiO2 and an iron tailing with 11.2% TiO2, with respective outputs of about 2.4 t / h, 2.1 t / h and 2.6 t / h. The carbon concentrate is used for the coking bed of the chlorination furnace, the titanium concentrate is first smelted into titanium-rich material in an electric furnace, and then the ore bed is made in the chlorination furnace, and liquid chlorine is passed into the chlorination furnace for chlorination reaction to generate titanium tetrachloride and coke black slag, thereby realizing the recycling of resources.

[0057] The carbon concentrate, titanium concentrate and iron tailings were subjected to quality tests based on the methods in GB / T 212-2008 and YS / T351-2015. Fixed carbon and elemental analysis tests were performed respectively. The test results are shown in Table 1.

[0058] Table 1 Process product quality test table

[0059] Component % <![CDATA[TiO2]]> <![CDATA[Fe2O3]]> CaO MgO <![CDATA[SiO2]]> <![CDATA[Al2O3]]> <![CDATA[Nb2O5]]> <![CDATA[Cr2O3]]> MnO <![CDATA[P2O5]]> <![CDATA[SO3]]> <![CDATA[K2O]]> <![CDATA[ZrO2]]> <![CDATA[Na2O]]> Cl C Coke black slag 28.3 8.3 0.2 0.3 8.2 0.8 1.3 0.3 1.5 0.1 7.4 1.4 0.0 2.4 8.1 31.0 Carbon concentrate 4.1 1.6 0.1 0.1 4.3 0.1 0.9 0.2 0.3 0.4 18.6 0.0 1.0 1.7 4.6 61.3 Titanium Concentrate 81.9 1.3 0.1 0.2 5.4 0.3 0.5 0.2 0.2 0.1 1.1 0.0 0.3 2.9 2.2 3.1 Iron tailings 11.2 21.7 0.1 0.4 16.6 2.2 1.0 0.4 1.3 0.3 3.6 0.0 0.9 2.5 6.1 31.0

[0060] Comparative Example 1

[0061] Compared with Example 1, the feed flow rate of step S2 is adjusted to 14m 3 / h, and the rest is the same as in Example 1. The test results of the obtained product are shown in Table 2.

[0062] Table 2 Process product quality test table

[0063] Component % <![CDATA[TiO2]]> <![CDATA[Fe2O3]]> CaO MgO <![CDATA[SiO2]]> <![CDATA[Al2O3]]> <![CDATA[Nb2O5]]> <![CDATA[Cr2O3]]> MnO <![CDATA[P2O5]]> <![CDATA[SO3]]> <![CDATA[K2O]]> <![CDATA[ZrO2]]> <![CDATA[Na2O]]> Cl C Coke black slag 16.1 7.0 0.2 0.7 11.5 0.9 0.7 0.3 1.5 0.4 13.0 0.0 0.8 1.0 7.3 38.4 Carbon concentrate 5.2 3.8 0.1 0.1 7.4 1.5 2.6 0.4 0.3 0.6 21.5 0.0 2.8 1.1 4.0 47.2 Titanium Concentrate 59.6 1.3 0.1 0.2 21.3 0.4 0.6 0.2 0.1 0.2 2.9 0.0 0.6 1.6 2.1 8.7 Iron tailings 16.1 19.0 0.1 0.6 16.8 2.8 1.7 0.5 1.6 0.4 8.6 0.0 1.9 1.9 6.1 21.2

[0064] Comparative Example 2

[0065] Compared with Example 1, the total flow rates of terpineol and light diesel in the flotation stage of step S2 are 1.20 kg / h and 2.5 kg / h, respectively. The rest are the same as Example 1. The test results of the obtained products are shown in Table 3.

[0066] Table 3 Process product quality test table

[0067] Component % <![CDATA[TiO2]]> <![CDATA[Fe2O3]]> CaO MgO <![CDATA[SiO2]]> <![CDATA[Al2O3]]> <![CDATA[Nb2O5]]> <![CDATA[Cr2O3]]> MnO <![CDATA[P2O5]]> <![CDATA[SO3]]> <![CDATA[K2O]]> <![CDATA[ZrO2]]> <![CDATA[Na2O]]> Cl C Coke black slag 16.7 8.2 0.2 0.6 11.4 1.3 2.0 0.3 1.4 0.5 12.4 0.0 2.0 0.9 8.5 32.9 Carbon concentrate 6.9 2.9 0.1 0.3 8.9 0.4 4.0 0.3 0.5 0.8 21.7 0.0 4.2 1.6 5.7 40.4 Titanium Concentrate 74.8 1.2 0.2 0.3 9.7 0.4 0.6 0.2 0.2 0.2 3.3 0.0 0.6 2.4 2.7 3.1 Iron tailings 21.2 19.4 0.2 0.7 25.7 3.8 0.9 0.6 1.5 0.2 3.5 0.0 1.0 4.2 8.4 7.9

[0068] Comparative Example 3

[0069] Compared with Example 1, the stroke of the shaking table in step S3 is 20 mm and the stroke frequency is 250 times / min. The rest is the same as Example 1. The test results of the obtained products are shown in Table 4.

[0070] Table 4 Process product quality test table

[0071] Component % <![CDATA[TiO2]]> <![CDATA[Fe2O3]]> CaO MgO <![CDATA[SiO2]]> <![CDATA[Al2O3]]> <![CDATA[Nb2O5]]> <![CDATA[Cr2O3]]> MnO <![CDATA[P2O5]]> <![CDATA[SO3]]> <![CDATA[K2O]]> <![CDATA[ZrO2]]> <![CDATA[Na2O]]> Cl C Coke black slag 15.3 6.6 0.2 0.6 12.4 1.0 1.1 0.3 1.4 0.4 12.3 0.0 1.1 0.9 9.8 35.7 Carbon concentrate 5.1 2.5 0.1 0.2 5.2 0.3 1.5 0.2 0.6 0.5 18.2 0.0 1.9 1.6 4.7 56.6 Titanium Concentrate 78.0 0.7 0.1 0.2 10.8 0.4 0.4 0.2 0.2 0.2 1.9 0.0 0.4 2.4 2.2 2.0 Iron tailings 18.5 2.1 0.1 0.2 45.1 1.3 2.1 0.4 0.2 1.0 10.6 0.0 2.3 1.7 3.6 10.1

[0072] Example 2

[0073] Compared with Example 1, the mass percentage concentration of the coal charred black slag in the slurry of step S1 is 20%, and the rest is the same as Example 1. The test results of the obtained products are shown in Table 5.

[0074] Table 5 Process product quality test table

[0075] Component % <![CDATA[TiO2]]> <![CDATA[Fe2O3]]> CaO MgO <![CDATA[SiO2]]> <![CDATA[Al2O3]]> <![CDATA[Nb2O5]]> <![CDATA[Cr2O3]]> MnO <![CDATA[P2O5]]> <![CDATA[SO3]]> <![CDATA[K2O]]> <![CDATA[ZrO2]]> <![CDATA[Na2O]]> Cl C Coke black slag 20.7 6.7 0.2 0.7 9.3 1.0 1.6 0.3 1.2 0.4 11.6 0.0 2.3 0.8 10.0 32.7 Carbon concentrate 6.5 2.3 0.1 0.2 4.1 0.3 1.8 0.2 0.5 0.4 16.7 0.0 2.5 1.3 5.1 57.2 Titanium Concentrate 83.2 1.1 0.2 0.4 7.2 0.4 0.3 0.2 0.3 0.1 0.5 0.0 0.3 2.5 2.7 0.5 Iron tailings 16.9 11.4 0.2 0.4 18.3 1.6 1.0 0.4 0.7 0.3 9.5 0.0 1.3 2.3 6.1 29.2

[0076] Example 3

[0077] Compared with Example 1, the mass percentage concentration of the coal charred slag in the slurry of step S1 is 15%, and the rest is the same as Example 1. The test results of the obtained products are shown in Table 6.

[0078] Table 6 Process product quality test table

[0079] Component % <![CDATA[TiO2]]> <![CDATA[Fe2O3]]> CaO MgO <![CDATA[SiO2]]> <![CDATA[Al2O3]]> <![CDATA[Nb2O5]]> <![CDATA[Cr2O3]]> MnO <![CDATA[P2O5]]> <![CDATA[SO3]]> <![CDATA[K2O]]> <![CDATA[ZrO2]]> <![CDATA[Na2O]]> Cl C Coke black slag 18.2 8.4 0.2 0.8 10.3 1.2 1.9 0.4 1.5 0.4 11.9 0.0 2.7 1.0 12.0 28.5 Carbon concentrate 3.8 1.7 0.1 0.2 2.6 0.2 2.2 0.1 0.5 0.5 17.6 0.0 2.9 1.4 4.4 61.1 Titanium Concentrate 87.9 0.6 0.1 0.1 6.1 0.3 0.3 0.2 0.1 0.1 0.3 0.0 0.4 1.5 1.4 0.4 Iron tailings 17.5 21.8 0.2 0.9 21.2 2.5 1.2 0.6 3.8 0.3 6.0 0.0 1.6 2.2 8.0 10.8

[0080] Example 4

[0081] Compared with Example 1, the mass percentage concentration of the coal charred black slag in the slurry of step S1 is 10%, and the rest is the same as Example 1. The test results of the obtained products are shown in Table 7.

[0082] Table 7 Process product quality test table

[0083] Component % <![CDATA[TiO2]]> <![CDATA[Fe2O3]]> CaO MgO <![CDATA[SiO2]]> <![CDATA[Al2O3]]> <![CDATA[Nb2O5]]> <![CDATA[Cr2O3]]> MnO <![CDATA[P2O5]]> <![CDATA[SO3]]> <![CDATA[K2O]]> <![CDATA[ZrO2]]> <![CDATA[Na2O]]> Cl C Coke black slag 27.9 5.4 0.3 0.4 11.0 0.7 1.9 0.2 0.9 0.5 7.1 0.0 2.1 0.8 8.2 32.0 Carbon concentrate 5.2 4.2 0.0 0.0 4.8 0.2 0.9 0.1 0.1 0.4 7.7 0.0 1.1 0.2 1.5 72.8 Titanium Concentrate 82.9 0.7 0.1 0.1 9.8 0.3 0.3 0.2 0.1 0.1 1.0 0.0 0.3 0.7 1.0 2.4 Iron tailings 17.6 7.4 0.3 0.2 23.5 0.6 1.5 0.3 0.5 0.6 9.6 0.0 1.8 0.9 1.6 33.2

[0084] Example 5

[0085] The method for separating and recycling the charred black slag of titanium dioxide ore by the chloride process provided in this embodiment is as follows: Figure 1 As shown, the specific steps include:

[0086] (1) A batch of 4t / h coal black slag containing 20.5% TiO2 and 30.7% carbon, which was washed and filtered by pressure from a chloride process titanium dioxide chlorination furnace, was prepared into a slurry with a coal black slag mass concentration of 10% in a stirring tank, the liquid level of the stirring tank was controlled at 1.9±0.5m, and the stirring was carried out at a speed of 100r / min for 10min;

[0087] (2) The slurry in step (1) was heated to 20 m 3 / h feed flow rate, pumped to the flotation machine through the pipeline, sucking 1.7m 3 / (m 2 *min) with a compressed air bubble of 40kPa at a gauge pressure to mix with the slurry; on the one hand, pine alcohol is added at a rate of 1 drop / s in flotation machines ① to ② for rough selection; then it enters flotation machines ③ to ④, pine alcohol is added at a rate of 1 drop / s and light diesel oil is added at a rate of 2 drops / s; then it enters flotation machines ⑤ to ⑥, pine alcohol is added at a rate of 2 drops / s and light diesel oil is added at a rate of 2 drops / s; then it enters flotation machines ⑦ to ⑧, pine alcohol is added at a rate of 1 drop / s and light diesel oil is added at a rate of 1.5 drops / s, so that the total flow rates of pine alcohol and light diesel oil in the flotation stage are 1.5kg / h and 3.0kg / h; the gate height is adjusted to control the liquid level so that the coking foam is scraped out by the scraper, and the scraper speed is 16r / min to obtain the coking foam and the tank bottom;

[0088] (3) automatically flowing the bottom of the slurry tank in step (2) onto the shaking table surface; controlling the stroke of the two-stage shaking table to 15 mm and the stroke frequency to 280 times / min, the tailings slurry obtained by the first-stage shaking table is further separated on the second-stage shaking table, and the obtained concentrate slurry is combined with the concentrate slurry of the first-stage shaking table to finally form a concentrate slurry and a tailings slurry;

[0089] (4) the coking foam in step (2), the concentrate slurry and the tailings slurry in step (4) are stored in respective storage tanks, and after reaching a certain liquid level, they enter the diaphragm filter presses for the coking foam, the concentrate slurry and the tailings slurry respectively; when the feeding is completed, a 1.0 MPa high-pressure fluid is injected into the diaphragm plate of each filter press to make the diaphragm bulge and compress the filter cake to dehydrate, and all the filtrate is recovered into the pulping tank;

[0090] (5) The filter cake discharged from the diaphragm filter press of the coking foam, concentrate slurry and tailings slurry in step (4) is dried in a convection or conduction dryer to obtain a carbon concentrate with 74.9% fixed carbon, a titanium concentrate with 89.7% TiO2 and an iron tailings with 28.2% TiO2. The respective outputs are approximately 1.6 t / h, 0.2 t / h and 2.2 t / h, respectively. The test results of the obtained products are shown in Table 8.

[0091] Table 8 Process product quality test table

[0092] Component % <![CDATA[TiO2]]> <![CDATA[Fe2O3]]> CaO MgO <![CDATA[SiO2]]> <![CDATA[Al2O3]]> <![CDATA[Nb2O5]]> <![CDATA[Cr2O3]]> MnO <![CDATA[P2O5]]> <![CDATA[SO3]]> <![CDATA[K2O]]> <![CDATA[ZrO2]]> <![CDATA[Na2O]]> Cl C Coke black slag 20.5 7.3 0.3 0.9 12.3 1.4 1.0 0.3 1.2 0.2 4.4 11.0 1.7 0.9 9.7 30.7 Carbon concentrate 3.1 3.1 0.0 0.1 2.5 0.6 0.7 0.2 0.1 0.2 4.5 11.3 1.1 0.2 1.2 74.9 Titanium Concentrate 89.7 0.4 0.2 0.1 6.4 0.4 0.3 0.2 0.1 0.0 0.1 0.2 0.3 0.6 0.9 0.1 Iron tailings 28.2 10.9 0.2 0.6 45.6 2.7 0.8 0.4 1.1 0.2 1.5 3.7 1.3 1.0 2.6 0.2

[0093] Although preferred embodiments of the present invention have been described, additional changes and modifications may be made to these embodiments by those skilled in the art once the basic inventive concepts are known. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention. Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A method for separating and recycling charred black slag from titanium dioxide ore produced by the chloride process, characterized in that: The following steps are involved: S1. Add water to the charred black slag of the chloride titanium dioxide ore and stir to make a slurry, control the stirring liquid level to be 0.3 to 0.5 m higher than the uppermost stirring blade, and obtain a slurry, wherein the mass percentage concentration of the charred black slag in the slurry is 10 to 30%; S2. The slurry is heated at 15 to 20 m 3 / h feed rate, adding flotation reagents, and 1.2~1.8m 3 / (m 2 * min) compressed air bubbling, sequentially through 4 stages of flotation separation, each stage of flotation respectively obtains coking foam and tank bottom, the coking foam from stages 1 to 4 is collected and combined, filtered and dried to obtain carbon concentrate, and the tank bottom from stages 1 to 3 is transported to the next stage of flotation; The flotation agent in the first stage of flotation is a frother, and the flow rate of the frother is 0.25-0.50 kg / h; The flotation reagents in the 2nd to 4th stage flotation are frothers and collectors; the flow rates of the frothers in the 2nd to 4th stage flotation are: 0.25-0.50kg / h, 0.50-1.00kg / h, 0.25-0.50kg / h; the flow rates of the collectors in the 2nd to 4th stage flotation are: 1.10-1.70kg / h, 1.10-1.70kg / h, 0.80-1.30kg / h; S3. The trough bottom of the fourth section is passed through a two-stage shaking table for ore belt separation, wherein the shaking table has a stroke of 8 to 20 mm and a stroke frequency of 250 to 360 times / min; wherein the roughing tailings from the first stage shaking table are passed through a scavenging table from a second stage shaking table, the roughing concentrate from the first stage shaking table and the scavenging concentrate from the second stage shaking table are combined, filtered and dried to obtain titanium concentrate, and the scavenging tailings from the second stage shaking table are filtered and dried to obtain iron tailings.

2. The method for separating and recycling charred black slag from titanium dioxide ore produced by the chloride process as claimed in claim 1, characterized in that: The stirring in step S1 adopts double-layer blade stirring, wherein when the height of the first layer of stirring blades is 0.54m and the height of the second layer of stirring blades is 1.54m, the stirring liquid level is controlled to be 1.8-2.0m.

3. The method for separating and recycling charred black slag from titanium dioxide ore produced by the chloride process as claimed in claim 1, characterized in that: In step S1, the stirring speed is not less than 90 r / min, and the stirring time is not less than 10 min.

4. The method for separating and recycling charred black slag from titanium dioxide ore by chloride process as claimed in claim 1, characterized in that: The gauge pressure of the compressed air in step S2 is 20-50 kPa.

5. The method for separating and recycling charred black slag from titanium dioxide ore by chloride process as claimed in claim 1, characterized in that: In step S2, the foaming agent is turpentine; and the collecting agent is light diesel.

6. The method for separating and recycling charred black slag from titanium dioxide ore produced by the chloride process as claimed in claim 1, characterized in that: In step S1, the titanium content in the coal-fired slag is 15-30% in terms of titanium dioxide, and the carbon content is 20-40% in terms of carbon element.

7. The method for separating and recycling charred black slag from titanium dioxide ore produced by the chloride process as claimed in claim 1, characterized in that: In step S2, the carbon content of the carbon concentrate is not less than 50% in terms of carbon element; the carbon concentrate is recycled to the chlorination furnace to produce titanium tetrachloride instead of part of the petroleum coke.

8. The method for separating and recycling charred black slag from titanium dioxide ore produced by the chloride process as claimed in claim 1, characterized in that: In step S3, the titanium content in the titanium concentrate is not less than 60% in terms of titanium dioxide; the titanium concentrate is recycled to a rotary kiln or an electric furnace for smelting to produce titanium chloride slag for use in a chlorination furnace to produce titanium tetrachloride.

9. The method for separating and recycling charred black slag from titanium dioxide ore produced by the chloride process as claimed in claim 1, characterized in that: In step S2, each stage of flotation is carried out by two flotation machines connected in series.

10. The method for separating and recycling charred black slag from titanium dioxide ore produced by the chloride process as claimed in claim 1, characterized in that: The filtration in steps S2 and S3 is performed by filter pressing equipment, and the filter pressing pressure is 0.5-1.3 MPa.

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