CN112024121A

CN112024121A - Vanadium titano-magnetite separation and extraction method

Info

Publication number: CN112024121A
Application number: CN202010898173.5A
Authority: CN
Inventors: 胡广华; 庞建明; 张群; 张翊
Original assignee: Chongqing Youti Industrial Co Ltd
Current assignee: Chongqing Youti Industrial Co Ltd
Priority date: 2020-08-31
Filing date: 2020-08-31
Publication date: 2020-12-04
Anticipated expiration: 2040-08-31
Also published as: CN112024121B

Abstract

The invention provides a vanadium titano-magnetite separation and extraction method, which comprises the steps of uniformly mixing vanadium titano-magnetite, an additive, a desulfurizer and a bonding agent, pressing into a cake-shaped material, and drying the cake-shaped material; adding the dried cake-shaped material and a carbon reducing agent into a reaction tank group, and placing the reaction tank group in a tunnel kiln filled with natural gas for roasting to obtain a roasted material; separating the roasted material from the reaction tank, screening, crushing, and performing multistage ball milling and multistage magnetic separation on the separated roasted material to obtain an iron material and a titanium material respectively; dehydrating and drying the titanium material to obtain a titanium product and a titanium byproduct; sorting the iron materials to obtain an iron primary product and an iron primary byproduct; filtering the iron primary product, drying and then carrying out secondary reduction to obtain an iron product; and filtering and drying the iron primary byproduct to obtain the iron byproduct. Compared with the traditional blast furnace ironmaking, the extraction method of the invention has no sintering and coking links, low energy consumption and little pollution.

Description

Vanadium titano-magnetite separation and extraction method

Technical Field

The invention belongs to the technical field of vanadium titano-magnetite separation, and particularly relates to a vanadium titano-magnetite separation and extraction method.

Background

The vanadium titano-magnetite is a composite mineral phase, is a solid solution composed of magnetite, ilmenite, magnesia-alumina spinel, ilmenite lamella crystals, fine-particle pyrrhotite lamella crystals and other ores, contains various valuable elements such as iron (Fe), vanadium (V), titanium (Ti) and the like, and has high comprehensive utilization value. The Panzhihua-Xichang area is the main mineral zone of the vanadium titano-magnetite in China, but the iron taste of the Panzhihua vanadium titano-magnetite is lower, and TiO is₂The content is higher, and since the beginning of the last 70 th century climbs the production of steel blast furnaces, the following problems mainly exist in the process flow of using the blast furnaces: firstly, 300 million tons of titanium-containing blast furnace slag are generated in blast furnace smelting every year, and the accumulated accumulation amount is hundreds of millions of tons, so that not only is the serious waste of titanium resources caused, but also huge environmental pressure is formed; secondly, the environmental pollution is serious, especially SO₂Dust and CO₂The discharge of (2) is high; thirdly, the iron-making process is long and the investment is large; fourthly, the whole system of iron, burning and coke is seen to be repeatedly heated, cooled, carbonized and decarburized, the recycling rate of resources and energy is low, and the utilization rate of heat energy is unreasonable.

Disclosure of Invention

In view of the deficiencies in the prior art, it is an object of the present invention to address one or more of the problems in the prior art as set forth above. For example, one of the purposes of the invention is to provide a vanadium titano-magnetite separation and extraction method with low energy consumption and little pollution.

The invention provides a method for separating and extracting vanadium titano-magnetite, which comprises the following steps: uniformly mixing vanadium titano-magnetite, an additive, a desulfurizer and a bonding agent, pressing into a cake-shaped material, and drying the cake-shaped material; adding the dried round cake-shaped material and a carbon reducing agent into a reaction tank group, and placing the reaction tank group in a tunnel kiln filled with natural gas for roasting to obtain a roasted material, wherein the roasting process comprises a preheating stage, a reduction stage and a cooling stage which are sequentially carried out, the temperature of the reduction stage is 1050-1200 ℃, and the time of the reaction stage is 6-8 hours; separating the roasted material from the reaction tank, screening, crushing, and performing multistage ball milling and multistage magnetic separation on the separated roasted material to obtain an iron material and a titanium material respectively; dehydrating and drying the titanium material to obtain a titanium product and a titanium byproduct; sorting the iron materials to obtain an iron primary product and an iron primary byproduct; filtering the iron primary product, drying and then carrying out secondary reduction to obtain an iron product; and filtering and drying the iron primary byproduct to obtain the iron byproduct.

The invention takes a tunnel kiln as a vanadium titano-magnetite reduction device. Introducing natural gas into the tunnel kiln for preheating, gradually heating the material, starting solid carbon reduction when the material temperature reaches about 800 ℃, combusting the separated CO in the upper space of the material layer, releasing heat for supplementary heating, and keeping the highest temperature at about 1400 ℃. And the precipitated CO can form a reducing atmosphere to reduce the iron oxide, and other metal oxides in the material do not react.

Compared with the prior art, the beneficial effects of the invention at least comprise at least one of the following:

(1) the method can reasonably separate and extract the titanium in the vanadium titano-magnetite, and compared with the traditional blast furnace ironmaking, the method can not generate a large amount of titanium slag to cause resource waste;

(2) the method has no sintering and coking links, and has high energy recycling rate, low energy consumption and little pollution.

Drawings

The above and other objects and features of the present invention will become more apparent from the following description taken in conjunction with the accompanying drawings, in which:

FIG. 1 shows a schematic flow diagram of a vanadium titano-magnetite separation and extraction process according to an exemplary embodiment of the present invention;

FIG. 2 shows a schematic flow diagram of a stock preparation process of an exemplary embodiment of the present invention;

FIG. 3 shows a schematic flow diagram of a firing process according to an exemplary embodiment of the present invention;

FIG. 4 shows a schematic view of a beneficiation process flow diagram according to an exemplary embodiment of the present invention;

FIG. 5 shows a schematic flow diagram of a reduction process according to an exemplary embodiment of the present invention;

FIG. 6 shows a material balance diagram of an exemplary embodiment of the present invention.

Detailed Description

Hereinafter, the vanadium titano-magnetite separation and extraction method according to the present invention will be described in detail with reference to the accompanying drawings and exemplary embodiments.

The invention provides a method for separating and extracting vanadium titano-magnetite. In one exemplary embodiment of the vanadium titano-magnetite separation and extraction method of the present invention, the extraction method may include:

s01, evenly mixing the vanadium titano-magnetite, the additive, the desulfurizer and the adhesive, pressing into a cake-shaped material, and drying the cake-shaped material. The vanadium titano-magnetite, the additive, the desulfurizer and the adhesive can be uniformly mixed in a stirrer. Suitable water, for example, may be added during stirring. Water with the mass of 4-6% of the mixed material can be added. The additive may be sodium carbonate. The addition amount of the sodium carbonate can be 1 to 3 percent of the mass of the vanadium titano-magnetite, the additive, the desulfurizer and the adhesive mixture. The addition of sodium carbonate in the above range can reduce the roasting reduction temperature, increase the reaction speed and increase the yield. Preferably, sodium carbonate may be added in an amount of 2%. The amount of the desulfurizer added can be 5 per mill to 1 percent of the mass of the vanadium titano-magnetite, the additive, the desulfurizer and the adhesive mixture, for example, the amount of the desulfurizer added can be 0.2 percent to 0.8 percent. The addition amount of the adhesive can be 1-3% of the mass of the vanadium titano-magnetite, the additive, the desulfurizer and the adhesive mixture. For example, the amount of the binder added may be 2%. The desulfurizer can be a magnesium desulfurizer or a magnesium-calcium composite desulfurizer and the like. The adhesive may be a conventional adhesive such as polyvinyl alcohol.

And S02, adding the dried round cake-shaped material and the carbon reducing agent into the reaction tank group, and placing the reaction tank group in a tunnel kiln filled with natural gas for roasting to obtain a roasted material, wherein the roasting process comprises a preheating stage, a reducing stage and a cooling stage which are sequentially carried out. The temperature of the reduction stage can be 1050-1200 ℃, and the time of the reaction stage can be 6-8 h. The carbonaceous reducing agent may be coke or washed coal. After natural gas is introduced for preheating, solid materials in the reaction tank are gradually heated, solid carbonization and reduction are started after the temperature reaches 800 ℃, separated CO is combusted in the upper space of the material layer, heat is released for supplementary heating, and the highest temperature can reach 1400 ℃. In order to maintain a reducing atmosphere in the bed, the carbonaceous reducing agent should be actually added in an amount greater than that theoretically required for the chemical reaction. Further, the addition amount of the carbon reducing agent may be 10% to 15% of the mass of the vanadium titano-magnetite, for example, the addition amount of the carbon reducing agent may be 12% of the mass of the vanadium titano-magnetite. The deep reduction of the vanadium titano-magnetite adopts a tunnel kiln, utilizes the high temperature point (up to 1400 ℃) generated in the combustion process of carbon monoxide generated by carbon to prepare a reducing agent and the additive with the addition amount, the high temperature point and the additive act together to destroy the iron-titanium bond, so that the iron oxide can be reduced into metallic iron to the maximum extent, the reduction rate of the metallic iron is more than 95%, the grain aggregation of the iron is used, the grain size of the iron is more than 100 meshes, the grain growth and the grain size of the iron can be adjusted, such as 0.5mm, and the aggregation of the iron grains realizes the separation of the titanium and the iron in the reduction stage.

And S03, separating the roasted material from the reaction tank, screening, crushing, and performing multi-stage ball milling and multi-stage magnetic separation on the separated roasted material to obtain an iron material and a titanium material respectively.

And S04, dehydrating and drying the titanium material to obtain a titanium product.

And S05, separating the iron materials to obtain an iron primary product and an iron primary byproduct.

S06, filtering the iron primary product, drying and then carrying out secondary reduction to obtain an iron product; and filtering and drying the iron primary byproduct to obtain the iron byproduct. The iron product is sponge iron. The sponge iron retains a large number of micropores formed during reduction and oxygen loss and is observed to be similar to a sponge under a microscope. The obtained sponge iron has low carbon and silicon contents, and the components are similar to steel, so the sponge iron can replace scrap steel for steelmaking. The carbon content in the sponge iron may be less than 0.9 mass%.

Note that S04 and S05 may be performed simultaneously without any order.

Furthermore, the diameter of the cake-shaped material can be 4 cm-6 cm, and the thickness can be 1.5 cm-2.5 cm. The round cake shape with the diameter and the thickness can ensure that the material has larger contact area with the reducing agent, the reduction of the iron element can be accelerated, and the reduction rate is increased. The diameter and thickness of the cake-like material are limited by the briquetting machine, and the diameter of the cake-like material is less than 4cm and the thickness is less than 1.5cm, which affects the charging amount and reduces the yield.

Further, the roasting process comprises a preheating stage, a reduction stage and a cooling stage which are sequentially carried out. The temperature of the preheating stage can be 100-300 ℃, and the preheating time can be 2-4 h; the temperature of the reduction stage can be 1050-1200 ℃, and the reduction time can be 6-8 h; the kiln discharging temperature of the cooling stage can be less than 200 ℃, and the time of the cooling stage can be 4-6 h. Preferably, the temperature of the preheating stage can be 180 ℃, and the preheating time can be 3 hours; the temperature of the reduction stage can be 1100 ℃, and the reduction time can be 420 min; the kiln discharging temperature of the cooling stage can be less than 200 ℃, the time of the cooling stage can be 5 hours, and the reduction rate can be ensured to be more than 97% while the energy consumption is saved under the preheating temperature, the preheating time, the reduction temperature, the reduction time, the cooling temperature and the cooling time. Further, the total time of the reaction tank undergoing the preheating stage, the reduction stage and the cooling stage may be 900min to 950 min.

Further, the moisture content of the dried tortilla material is less than 2%, for example, the moisture content is 1%.

Further, the reaction tank group may be constituted by a plurality of reaction tank layers stacked on each other. Each reaction tank layer is composed of a plurality of reaction tanks connected in parallel. Each reaction tank in the uppermost reaction tank layer is provided with a tank cover. For example, the set of reaction tanks may be arranged in 4 layers of 4 × 20 reaction tanks each. The reaction tank may be a silicon carbide tank. The top of the uppermost reaction tank is covered, so that in order to prevent fire from being mixed into the reaction tank, excessive CO is combusted at the edge of the cover (no CO combustion at the edge of the cover is one of indications of completion of the reduction reaction), and a slight negative pressure is formed in the top layer of the reaction tank, so that the flow of the reduction gas in the tank is promoted, and the balance of the reduction reaction is promoted.

Further, the multistage ball milling and multistage magnetic separation may include:

s301, carrying out primary wet ball milling on the crushed roasting material to obtain a primary ball milling material with the particle size of 70-90 meshes. For example, the water content can be controlled to 63%, and the particle size can be controlled to 82 mesh first-stage ball-milled material. The water content of the first-stage wet ball milling can be more than 50%.

S302, performing dehydration treatment on the primary ball-milled material, performing primary magnetic separation on the dehydrated primary ball-milled material to obtain a primary iron material and a primary titanium material, and performing demagnetization treatment on the primary iron material. Through the primary magnetic separation treatment, iron can be separated from the dehydrated primary ball-milled materials to the maximum extent to form reduced iron (primary iron material) and rich slag (primary titanium material). At this time, TiO contained in the primary iron material₂The mass ratio of (A) is within 3 percent, and the mass ratio of Fe contained in the first-grade titanium material is controlled within 3 percent. The demagnetizing treatment of the primary iron material can break the magnetic agglomeration generated by magnetic separation, thereby facilitating the subsequent secondary magnetic separation.

S303, carrying out secondary magnetic separation on the demagnetized primary iron material and the demagnetized primary titanium material to obtain a secondary iron material and a secondary titanium material. The secondary magnetic separation mainly aims at reducing carbon and impurities, and removing residual carbon and harmful slag in the secondary titanium material to the maximum extent to form a high-grade titanium product.

S304, carrying out secondary wet ball milling on the secondary titanium material to obtain a secondary ball-milled titanium material.

S305, performing three-stage magnetic separation on the secondary iron material and the secondary ball-milled titanium material respectively to obtain an iron material and a titanium material.

Further, after multi-stage ball milling and magnetic separation, wastewater generated in the processes of primary wet ball milling and secondary wet ball milling is collected. Vanadium pentoxide is dissolved in the wastewater. After coal ash impurities are removed through precipitation, vanadium pentoxide in the wastewater is enriched, and when the vanadium pentoxide reaches a preset concentration, the vanadium pentoxide is extracted through a resin exchange method. The predetermined concentration may be an empirical value or a given value.

Further, the secondary reduction may include reduction using hydrogen at a temperature of 900 to 1000 ℃. The hydrogen gas used for the reduction here may be hydrogen gas produced by decomposition of ammonia. Specifically, the ammonia decomposition gas generation device takes liquid ammonia as a raw material, heats ammonia gas after vaporization, and decomposes the ammonia into a hydrogen-nitrogen mixed gas under the action of a catalyst. Residual ammonia and water in the mixed gas can be removed by using a gas purifier, satisfactory protective gas is obtained, and the generated hydrogen is used for reducing iron.

Further, the vanadium titano-magnetite may be washed vanadium titano-magnetite concentrate (TiO)₂The mass ratio of (B) can be more than 47 percent), and the mineral component is mainly titanomagnetite [ mFe n (Fe. TiO)₂)]And secondly ilmenite (FeO. TiO)₂) And ferrotitanium spinel (2 FeO. TiO)₂). The reducing power of iron oxide in the vanadium-titanium-iron ore concentrate is more complex than that of the common iron ore concentrate. Initially Fe in solid solution in titanomagnetite₃O₄Reduction to the pumice (Fe)_xO), and then reducing the pumice body to metallic iron.

In one embodiment, as shown in fig. 1, the vanadium titano-magnetite separation and extraction method may include the steps of:

the method comprises the following steps of carrying out dust-free bag breaking, feeding and metering operations on materials consisting of the raw materials of the vanadium titano-magnetite, the additive, the desulfurizer and the adhesive in a dust-free feeding station, and conveying the materials to a stirrer through a pipe chain. Adding a predetermined amount of water into the stirrer during stirring, uniformly mixing, pelletizing in a ball press, and pressing to obtain a cake-shaped material. Mixing the round cake-shaped material and reducing agent coke, canning and loading on a vehicle. And the rockers after charging are pushed one by one to enter the kiln through a stepping machine prepared by the tunnel kiln. And then heating the tunnel kiln by burning natural gas in the tunnel kiln. And (3) carrying out air cooling and water cooling on the roasted material after the reduction roasting is finished, and demoulding and unloading after the cooling is finished. The roasted material enters a sieving machine through a storage bin and a feeding machine. And after the screening is finished, the materials are hermetically conveyed to a jaw crusher by using a belt, and are crushed by the jaw crusher and a fine crusher connected with the jaw crusher to be subjected to multistage ball milling and multistage magnetic separation. And (4) obtaining a non-magnetic material (titanium material) and a magnetic material (iron material) after the multi-stage ball milling and the multi-stage screening are finished. The non-magnetic material is filtered, dried and bagged to obtain a titanium product and a titanium byproduct. And (4) sorting the magnetic material by a multistage shaking table to obtain an iron primary product and an iron primary byproduct. And filtering and drying the primary iron by-product to obtain the iron by-product which can be bagged. And filtering the iron primary product, drying, and performing secondary reduction to obtain the iron product capable of being bagged.

Specifically, the vanadium titano-magnetite separation and extraction method can comprise a material preparation process flow, a roasting process flow, a mineral separation process flow and a reduction process flow.

As shown in fig. 2, the preparation process may include the following steps:

and S1001, unpacking and transferring the raw materials and auxiliary materials. The raw material is vanadium titano-magnetite, and the auxiliary materials are additive, desulfurizer and adhesive. The forklift transports bagged materials (excluding reducing agent coke) from a raw and auxiliary material storage area to a production area, and the raw and auxiliary materials are subjected to bag breaking, feeding and metering through an automatic bale breaker and a pipe chain conveyor, so that dust-free operation is realized. The raw and auxiliary materials are bagged, and the materials after being subjected to bag breaking and metering are conveyed to the stirrer through a pipe chain. The raw and auxiliary materials are the general names of raw materials and auxiliary materials.

And S1002, feeding and mixing the raw materials and the auxiliary materials. The pipe chain conveyor conveys the measured raw and auxiliary materials (except coke) into the stirrer, and an integral closed cover (provided with a door and a window and convenient for manual feeding of a small amount of materials) is arranged outside the stirrer. And (3) allowing dusty airflow generated in the stirring process to enter a No. 1 bag type dust collector for purification treatment, and mixing materials in a closed operation. After 5 percent of water of the material quantity (raw and auxiliary materials) is added and stirred, the discharging of the stirrer is wet material, and discharging flying dust is not considered.

The dust-containing gas flow in the blending area (generated in the stirring process) is G1, and is discharged through a No. 1 exhaust funnel with the height of 15m after being processed by a No. 1 bag type dust collector to reach the standard. Recycling the dust of the No. 1 bag type dust collector into the stirrer.

And S1003, performing ball pressing treatment on the stirred raw and auxiliary materials. And conveying the stirred raw and auxiliary materials to a ball press by using a belt conveyor. Adding water, mixing uniformly, adding the mixture into a ball press, and pressing into a cake-shaped material with the diameter of 5cm and the thickness of 2cm, wherein the material has a certain viscosity.

As shown in fig. 3, the firing process flow may include the following steps:

and S1004, drying the pressed round cake-shaped material. Cake-shaped materials (namely material balls) are transported to a roasting workshop through a trailer, enter a tower type dryer through a belt conveyor, and are dried by utilizing the waste heat of cooling air of a tunnel kiln, and the moisture content is reduced to below 2 percent from 5 percent. For the moisture content of the cake shape, if the moisture is more than 2%, the energy consumption is increased, and the preheating utilization is insufficient. Preferably, the moisture content is between 0.5% and 2%. If the moisture content is too small, the capacity of the waste heat utilization dryer apparatus needs to be increased, which is uneconomical. The pellet may use a polymer composite cellulose binder. The addition amount of the adhesive can be not more than 2% of the mass of the mixed materials, the adhesive has high bonding strength, the adhesive does not scatter or crack in the transferring and drying process, the drying air volume is small, dust generation is not considered, an exhaust funnel does not make statistics, and certain noise N is generated.

And S1005, canning the material. And adding the dried cake-shaped material into a silicon carbide reaction tank. Putting an annular mold into a silicon carbide tank, putting a material ball into the middle of the mold through a spiral feeding machine with an adjustable angle, putting coke into an outer ring of the mold, taking out the mold after the charging is finished. The coke can also be fed using a screw feeder. The material balls are hard, dust is not easy to generate in the charging process, and filling dust G2 is generated when coke enters the reaction tank. The canning dust-generating point is close to the wet-type flue gas treatment facility, G2 is directly discharged into the wet-type flue gas purification device, and the dust is discharged through the No. 4 exhaust funnel after being removed.

And S1006, jacking the furnace and entering the furnace. And (4) the kiln cars which finish material canning are pushed one by one to enter the kiln through a stepping machine matched with the tunnel kiln.

And S1007, roasting in a tunnel kiln. The kiln car enters the tunnel kiln, is taken out of the kiln after being roasted for 900min by the preheating zone, the roasting zone and the cooling zone, and averagely enters and exits one kiln car every 15 min. When the furnace temperature is 850 ℃, the coke begins to be subjected to solid carbon reduction, the separated CO forms a reducing atmosphere, the iron oxide is subjected to a reduction reaction, and other metal oxides in the material are not reacted. To prevent fire clusters into the silicon carbide canister, the top most layer of the silicon carbide canister was capped, excess CO was burned at the cap rim (no CO combustion at the cap rim is one of the indicators of completion of the reduction reaction),and micro negative pressure is formed in the top layer of the silicon carbide tank, so that the flow of reducing gas in the tank is promoted, and the balance of reduction reaction is promoted. Sulfur in the raw and auxiliary materials generates COS in the CO atmosphere, the COS is transferred from a solid phase to a gas phase and escapes from the reaction tank, and the COS and shale gas (natural gas) are combusted together in a hearth to generate SO₂. The combustion of shale gas will produce certain SO₂NOx and particulate matter. The roasting flue gas of the tunnel kiln is G6, and is discharged by a No. 4 exhaust funnel after being desulfurized and dedusted by a wet flue gas purification device. A single tunnel kiln can be provided with 10 fans, 5 for 5. The absorption liquid can generate gypsum during regeneration, and the gypsum is collected as common solid waste and is recycled after dehydration.

And S1008, discharging from the kiln. The volume of the roasted material is reduced in the heating process, the roasted material is naturally separated from the reaction tank, and the reaction tank does not need to be cleaned. The loading and unloading worker transports the burden to a burden storage bin. The kiln car after unloading enters a loading area through a stepper.

As shown in fig. 4, the beneficiation process flow includes multistage ball milling and multistage magnetic separation, and the beneficiation process flow may include the following steps:

s1009, screening the roasted materials. The roasted material after demoulding and unloading is transported to a storage bin and a feeder through a trailer and then enters a sieving machine. The roasted material has certain hardening property, and almost no dust is generated in the process of transferring the roasted material to a storage bin and a feeder. The furnace burden is mutually extruded and collided under the action of a vibrating screen classifier, material balls and coke are separated, wherein the material balls are kept in an original state, carbon slag is pulverized and screened off, certain dust is generated, and a 3-1# integral closed cover is arranged.

S1010, crushing by a jaw crusher: and (4) feeding the screened material balls into a jaw crusher through a closed belt conveyor, and crushing the material balls to be less than 20 mm. The interior of the jaw crusher is closed, and the inlet and the outlet are provided with closed covers for collecting raised dust.

And S1011, crushing by a fine crusher. And (4) crushing the materials crushed by the jaw crusher again by the fine crusher.

The closed belt conveyor is connected with an inlet of the fine crusher, and the materials crushed by the jaw crusher of the fine crusher are crushed to be below 8 mm. The interior of the fine crusher is closed, and a closed cover is arranged at the inlet and the outlet.

And S1012, transferring in a storage bin. The fine crusher discharges to the transfer feed bin, delivers to the ball mill through batcher and band conveyer and carries out wet-type ball-milling with the material. The junction of the feeder and the belt conveyor is arranged in a closed way.

The particulate matters produced by the sieving machine, the jaw crusher, the fine crusher, the storage bin and the feeder 4 are counted as G3, and are discharged through a 2# exhaust funnel with the height of 15m after being treated by a 2# bag type dust collector. And recycling the dust of the dust removal facility into the mixer.

And S1013, carrying out primary wet ball milling. The first-stage ball mill is used to ball mill the crushed calcined material to a particle size of 70 to 90 mesh, for example, 80 mesh. The water content of the material is more than 50 percent, and no dust is generated.

S1014, cyclone dehydration. The first-stage ball-milled material after the first-stage wet ball milling has larger water content, and after centrifugal dehydration by a swirler, the material enters a magnetic separator. The cyclone is centrifugally dewatered to produce waste water.

And S1015, performing primary magnetic separation. The water content of the ball-milled material is high, after solid-liquid separation is carried out by a cyclone, the water content is not more than 60%, the ball-milled material enters a primary magnetic separator for magnetic separation, and a magnetic iron material and a magnetic titanium material are separated to respectively obtain a primary iron material (magnetic material) and a primary titanium material (non-magnetic material). The permanent magnet roller removes the magnetic material by high pressure water.

And S1016, demagnetizing. And the primary iron material after the primary magnetic separation enters a demagnetizer to break magnetic agglomeration generated by the magnetic separation, so that the subsequent secondary magnetic separation is facilitated.

S1017, secondary magnetic separation. And respectively carrying out secondary magnetic separation on the primary titanium material subjected to the primary magnetic separation and the demagnetized primary iron material to respectively obtain a secondary iron material and a secondary titanium material. The secondary magnetic separation can further improve the purity of the titanium product and the iron product.

And S1018, secondary ball milling and screening. And (3) carrying out secondary wet ball milling on the non-magnetic material secondary titanium material, screening by using a grinding head screen, and feeding the screened material into the ball mill again. And obtaining a secondary ball-milling titanium material after ball milling is finished.

S1019, carrying out three-stage magnetic separation on the titanium material. And performing three-stage magnetic separation on the nonmagnetic material secondary ball-milled titanium material, and dewatering the titanium material subjected to magnetic separation in a concentration hopper. And adding the magnetic material obtained after the third-stage magnetic separation into the second-stage iron material to carry out third-stage magnetic separation together with the second-stage iron material.

And S1020, concentrating and filtering the titanium material. The titanium material is dehydrated by gravity of a concentration hopper and then is dehydrated by a disc filter, and the material enters a dryer through a belt conveyor and a spiral feeding machine.

And S1021, drying the titanium material. The hot air cooled by furnace burden is adopted for direct drying, the dust-containing airflow enters a cyclone dust collector arranged on the dryer for treatment, the dust is returned to the dryer, and the dust-containing airflow G4 enters a No. 3 bag type dust collector for further dust removal treatment.

And S1022, bagging the titanium material. The temperature of the dried titanium product is 45-50 ℃, and the dried titanium product is hermetically conveyed to a storage bin of a full-automatic bagging machine through a closed belt conveyor, weighed and bagged. The bag filling machine feeds materials spirally, automatically feeds bags and feeds materials in vacuum, and the automatic bag filling link hardly generates dust.

And S1023, carrying out three-stage magnetic separation on the iron material. And carrying out three-stage magnetic separation on the second-stage iron material. And adding the non-magnetic material selected in the three-stage magnetic separation process into the titanium material concentration and filtration step for concentration and filtration.

And (3) flushing the first three-stage magnetic materials from the magnetic separator through high-pressure water flow, dewatering the magnetic materials in a No. 1 iron material concentration hopper, and then carrying out magnetic separation on the iron materials. Production wastewater is generated.

And S1024, sorting by a shaking table. And conveying the iron material subjected to magnetic separation to a shaking table separation area through a slurry pump. Under the action of water flow flushing and bed surface vibration, the iron material separates the iron product with high density and high purity from the iron by-product with low density and low taste to obtain the primary iron product and the primary iron by-product.

And S1025, concentrating and filtering the iron material. The iron material is separated into an iron primary product and an iron primary byproduct by a table concentrator, then enters a No. 2 iron material concentration hopper for gravity dehydration, and then enters an iron material disc vacuum filter for dehydration, wherein the water content of the product is about 20%.

S1026, drying the iron product and the iron byproduct. The hot-air after the design adopts the heat transfer of tunnel cave quench zone is as the heat source of stoving iron product, because sponge iron is easy to be oxidized, adopts indirect drying mode, and dusty tail gas G5 volume is little but the water content is great, gets into behind the further recovery product of 4# bag collector, discharges through 3# aiutage.

S1027, bagging the iron byproduct. The dried iron by-product is vacuum bagged and has certain noise N.

S1028, transferring the iron product and carrying out secondary reduction. In order to ensure that the dried iron material is not oxidized in the air as much as possible, the iron material is conveyed to a secondary reduction workshop by a pipe chain conveyor for secondary reduction. There is a certain noise N in the conveying process.

As shown in fig. 5, the reduction process flow may include the following steps:

s1029, conveying by a pipe chain. The iron powder produced by solid reduction is spongy inside and is partially oxidized in the processes of cooling and beneficiation. And conveying the dried iron material (the dried iron primary product) to a reduction workshop through a pipe chain. There is a certain noise N.

And S1030, decomposing and purifying ammonia gas. The ammonia gas is decomposed into mixed gas of hydrogen and nitrogen under the action of nickel catalyst at 800 deg.C (electrically heated), and the ammonia gas concentration is less than or equal to 2 PPm. The mixed gas of hydrogen and nitrogen after ammonia decomposition contains certain moisture under the influence of the purity of liquid ammonia. The kaolin molecular sieve is used for dewatering, and two dewatering and purifying devices containing the kaolin molecular sieve are used alternately. Because the reduction process of the iron material cannot contain oxygen, the kaolin molecular sieve adopts nitrogen to blow off moisture to realize regeneration, and the nitrogen and the blown off moisture are discharged outdoors without statistics. A carbon molecular sieve nitrogen making machine (air nitrogen making machine) is adopted to filter oxygen from air to obtain nitrogen. The ammonia decomposition and purification processes are closed operations, and certain noise N is generated.

And S1031, carrying out secondary reduction. The iron material (the dried iron primary product) is uniformly distributed in a steel belt type reduction furnace, the steel belt type reduction furnace is electrically heated to 950 ℃, and the iron oxide is secondarily reduced in hydrogen. The surplus hydrogen which does not participate in the reaction is combusted at the furnace end, and the exhaust funnel of the furnace is not counted.

S1032, crushing the iron material. The reduced iron powder has a hardened condition, the iron powder is crushed and discharged in a nitrogen protective atmosphere through a crusher, tail gas has certain dust G7, and the tail gas is introduced into a No. 1 bag type dust collector nearby for treatment. The iron product bags are the same as the titanium product bags.

In the invention, the multi-stage ball milling, the magnetic separation and the table concentrator are wet operations, the production wastewater after solid-liquid separation is recycled after precipitation treatment, fresh water is supplemented to the production wastewater every day, bottom mud is discharged irregularly (recycled as a byproduct), and the water quality requirement of the process wastewater can be met. The flue gas generated by wet operation adopts a double-alkali method, and the regenerated absorption liquid is recycled and is not discharged outside. Cooling water generated by cooling materials in the extraction process is recycled, and concentrated water generated by preparing reverse osmosis pure water is clean sewage and is discharged into a rainwater pipe network.

According to the above S1001 to S1032, the material balance in the ilmenite separation and extraction process is shown in Table 1.

TABLE 1 Material balance Table

Note: the iron product and the titanium product contain other impurities, mainly ferrotitanium compound which is not completely reacted, carbon residue, gangue and Na₂CO₃CaO, etc.; secondly, separating the carbon slag and the desulfurizer thereof from the material balls in a screening link, wherein the actual separation is not thorough, and the actual yield is slightly less than a theoretical value; ③ the final product after the high-temperature carbonization and reduction reaction of the adhesive is CO₂And H₂O, counting the weight loss of the material by high-temperature reduction; and fourthly, the discharged particle amount contains smoke dust removed by wet treatment and does not contain dust removed ash recovered as raw and auxiliary materials and byproducts.

The material balance diagram of the main process flow according to the material input of table 1 is shown in fig. 6. The main flow comprises the steps of transferring and batching 100000t/a titanium concentrate raw material and 4450t/a auxiliary material (comprising 2000t/a additive, 450t/a desulfurizer and 2000t/a binder), wherein the dust-containing gas flow G1 generated in the batching and stirring process is 26.88 t/a. The No. 1 dust remover collects the dusty gas flow which is not discharged disorderly in the dusty gas flow G1, and the No. 1 dust remover collects the dusty gas flow G7 and feeds the collected dusty gas flow into the stirrer again for recycling (the dusty gas flow 30.508 fed into the stirrer is 26.88-1.28+ 5.2-0.292). After stirring, pressing the balls, canning, and mixing with coke in the canning process. The dust G2 generated during the canning process was 0.201 t/a. After the flue gas is roasted by the tunnel kiln, the wet flue gas treatment equipment collects the raised dust G2 generated by canning and the flue gas G6 generated by roasting by the tunnel kiln, part of the flue gas enters alkali liquor for recovery, and the other part of the flue gas is organically discharged (the specific numerical values are shown in figure 6). And after roasting is finished, screening to store the carbon slag and the CaS by using a common solid waste warehouse. The dust-containing air flow generated by sieving and jaw crushing is collected by a No. 2 dust remover. Part of smoke dust in the No. 2 dust remover is discharged in an organized manner, and the rest dust is recycled in the multi-stage ball milling and magnetic separation processes. And after multi-stage ball milling and magnetic separation, respectively carrying out filter pressing on the obtained iron material and titanium material, and then drying. And collecting dust-containing gas flow G4 generated by filter pressing and drying of the titanium material by using a No. 3 dust remover. The dusty gas stream G5 generated by the iron charge was collected by a # 4 dust collector. Reducing, crushing and bagging the filter-pressed and dried iron material for the second time, and bagging the filter-pressed and dried titanium material. The units of the numerical values in fig. 6 are all t/a, and the content change related to the specific process is shown in fig. 6.

Although the present invention has been described above in connection with exemplary embodiments, it will be apparent to those skilled in the art that various modifications and changes may be made to the exemplary embodiments of the present invention without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. A vanadium titano-magnetite separation and extraction method is characterized by comprising the following steps:

uniformly mixing vanadium titano-magnetite, an additive, a desulfurizer and a bonding agent, pressing into a cake-shaped material, and drying the cake-shaped material;

adding the dried round cake-shaped material and a carbon reducing agent into a reaction tank group, and placing the reaction tank group in a tunnel kiln filled with natural gas for roasting to obtain a roasted material, wherein the roasting process comprises a preheating stage, a reduction stage and a cooling stage which are sequentially carried out, the temperature of the reduction stage is 1050-1200 ℃, and the time of the reaction stage is 6-8 hours;

separating the roasted material from the reaction tank group, screening, crushing, and performing multistage ball milling and multistage magnetic separation on the separated roasted material to obtain a titanium material and an iron material respectively;

dehydrating and drying the titanium material to obtain a titanium product and a titanium byproduct;

sorting the iron materials to obtain an iron primary product and an iron primary byproduct;

filtering the iron primary product, drying and then carrying out secondary reduction to obtain an iron product;

and filtering and drying the iron primary byproduct to obtain the iron byproduct.

2. The separation and extraction method of vanadium titano-magnetite as claimed in claim 1, characterized in that the multi-stage ball milling and multi-stage magnetic separation comprises:

carrying out primary wet ball milling on the crushed roasting material to obtain a primary ball milling material with the particle size of 70-90 meshes;

performing dehydration treatment on the primary ball-milled material, performing primary magnetic separation on the dehydrated primary ball-milled material to obtain a primary iron material and a primary titanium material, and performing demagnetization treatment on the primary iron material;

respectively carrying out secondary magnetic separation on the primary iron material and the primary titanium material after the demagnetizing treatment to respectively obtain a secondary titanium material and a secondary iron material;

carrying out secondary wet ball milling on the secondary titanium material to obtain a secondary ball milled titanium material;

and respectively carrying out three-stage magnetic separation on the second-stage iron material and the second-stage ball-milled titanium material to respectively obtain a titanium material and an iron material.

3. The method for separating and extracting vanadium titano-magnetite as claimed in claim 2, wherein the multi-stage ball milling and multi-stage magnetic separation further comprises collecting waste water generated in the primary wet ball milling and the secondary wet ball milling, removing coal ash in the waste water, and extracting vanadium pentoxide in the waste water by a resin exchange method.

4. The separation and extraction method of vanadium titano-magnetite according to any one of claims 1 to 3, characterized in that the diameter of the cake-like material is 4cm to 6cm and the thickness is 1.5cm to 2.5 cm.

5. The separation and extraction method of vanadium titano-magnetite according to any one of claims 1 to 3, characterized in that the separated roasting material is sieved, and the crushing includes controlling the particle size of the sieved roasting material below 8 mm.

6. The vanadium titano-magnetite separation and extraction method according to any one of claims 1 to 3, characterized in that the reaction tank group is composed of a plurality of reaction tank layers stacked on one another, each reaction tank layer is composed of a plurality of reaction tanks connected in parallel, and each reaction tank in the uppermost reaction tank layer is provided with a tank cover.

7. The separation and extraction method of vanadium titano-magnetite according to any one of claims 1 to 3, characterized in that the preheating stage comprises preheating at 100 ℃ to 300 ℃ for 2h to 4h, and the cooling stage comprises controlling the temperature of the exit tunnel kiln to be less than 200 ℃ and the cooling time to be 4h to 6 h.

8. The separation and extraction method of vanadium titano-magnetite according to any one of claims 1 to 3, characterized in that the secondary reduction comprises reduction with hydrogen at a temperature of 900 ℃ to 1000 ℃.

9. The method for separating and extracting vanadium titano-magnetite according to any one of claims 1 to 3, characterized in that the vanadium titano-magnetite is washed vanadium titano-magnetite concentrate, TiO in the vanadium titano-magnetite concentrate₂The mass ratio is more than 47%, and the mineral components in the vanadium-titanium-iron ore concentrate comprise titanomagnetite, ilmenite and ilmenite.

10. The method for separating and extracting the vanadium titano-magnetite according to any one of claims 1 to 3, characterized in that the additive is sodium carbonate, and the addition amount of the additive is 1% to 3% of the mixing mass of the vanadium titano-magnetite, the additive, the desulfurizing agent and the adhesive.