CN103966423A - Method for re-concentrating vanadium-titanium magnetite concentrate through alkaline leaching, acid pickling and re-selection - Google Patents

Abstract

The invention discloses a method for re-selecting vanadium-titanium magnetite concentrate by alkali leaching, pickling and re-selection, which comprises the following steps: placing the vanadium-titanium magnetite concentrate in an alkali solution with a mass concentration of 5-52%, Alkali leaching reaction at 370°C for 0.5 to 5 hours, filtering to obtain filtrate and alkali leaching filter cake A; add water to A to prepare a slurry with a solid-liquid mass ratio of 1:1 to 10, and then place it in a mass concentration of 1 to 10%. H ₂ SO ₄ solution, pickling at 50°C to 90°C for 5 to 60 minutes, filtering to obtain filtrate and acid leaching filter cake B; then adding water to acid leaching filter cake B to make Slurry is re-selected to obtain iron concentrate C with TFe content of 65%-68%, titanium concentrate ET with _TiO2 content of 55%-80%, and final tailings D with _SiO2 content of 57-61%. The advantages of the present invention are: high-efficiency sorting of vanadium-titanium magnetite concentrates is achieved, the alkali consumption is low, the content of impurities such as Al, Si, TiO ₂ and S entering the blast furnace is reduced, the utilization factor of the blast furnace is improved, and the cost of ironmaking is reduced. The comprehensive utilization rate of titanium resources has been improved.

Description

The method of re-selecting vanadium-titanium magnetite concentrate by alkali leaching, pickling and gravity separation

technical field

The invention relates to a beneficiation process of vanadium-titanium magnetite concentrate, in particular to a method for re-selecting vanadium-titanium magnetite concentrate by alkali leaching, pickling and gravity separation.

Background technique

Vanadium-titanium magnetite is a compound ore of multi-metal elements, which is a symbiotic magnetite mainly containing iron, vanadium and titanium. The vanadium-titanium magnetite concentrate is one of the products obtained from vanadium-titanium magnetite through ore dressing, in which vanadium exists in the titanium magnetite in the same quality and isomorphism to replace high-valent iron ions. Titanomagnetite is the main crystal mineral (Fe ₃ O ₄ ) and guest crystal ore [ilmenite spar 2FeO·TiO ₂ , ilmenite FeO·TiO ₂ , aluminum magnesium spinel (Mg,Fe) (Al,Fe ) ₂ O ₄ ] complexes formed. For example, the chemical multi-element analysis results of vanadium-titanium magnetite raw ore and vanadium-titanium magnetite concentrate after iron selection in Midi Concentrator in Panzhihua, China are shown in Table 1. The vanadium-titanium magnetite raw ore and vanadium-titanium magnetite concentrate The analysis results are shown in Table 2 and Table 3, respectively.

Table 1 Chemical multi-element analysis results of raw ore and vanadium-titanium magnetite concentrate of Midi concentrator in Panzhihua, China

element TF FeO mFe S _{Fe2O3 _} TiO ₂ V ₂ O ₅ Raw ore 29.53 21.36 20.20 0.631 17.70 10.54 0.278 Concentrate 54.01 32.42 51.16 0.574 40.97 12.67 0.61 element SiO ₂ Al ₂ O ₃ CaO MgO co P As Raw ore 22.80 7.65 6.36 7.23 0.02 0.015 <0.01 Concentrate 3.21 3.30 0.98 2.90 0.02 0.008 <0.010

Table 2 Results of chemical phase analysis of vanadium-titanium magnetite raw ore titanium and iron in Midi concentrator in Panzhihua, China

Table 3 Chemical phase analysis results of titanium and iron in the vanadium-titanium magnetite concentrate of Midi concentrator in Panzhihua, China

The vanadium-titanium magnetite resources are abundant in the world, with reserves of more than 40 billion tons in the world and 9.83 billion tons in China. Iron in vanadium-titanium magnetite ore mainly occurs in titanomagnetite, and TiO ₂ in the ore mainly occurs in granular ilmenite and titanomagnetite. Generally, about 57% of titanium occurs in titanomagnetite (mFeTiO ₃ ·nFe ₃ O ₄ ), and about 40% of titanium occurs in ilmenite (FeTiO ₃ ). The ore has complex composition and special properties, so the comprehensive utilization of this kind of ore is a major problem that has not been completely solved in the world. The occurrence characteristics of vanadium-titanium magnetite minerals determine that the effective separation of titanium and iron from the source of the ore cannot be achieved by physical beneficiation methods, resulting in low iron concentrate grades (TFe<55 %), the titanium in the iron concentrate completely enters the blast furnace slag (TiO ₂ content is more than 22%) to form a glass body during the ironmaking process, and the TiO ₂ loses its activity and cannot be economically recovered. At the same time, the titanium recovery rate is as low as 18%. Therefore, the selection of ilmenite ore by physical beneficiation method greatly reduces the value of titanium and iron alone.

China is the first country in the world to comprehensively extract iron, vanadium and titanium from complex vanadium-titanium magnetite on an industrial scale. , using the usual gravity separation, magnetic separation, flotation and other physical beneficiation methods to separate titanium and iron, the efficiency is low, and it is difficult to select titanium concentrate or iron concentrate with high grade and less impurities; at the same time, TiO ₂ The recovery efficiency is not high. After the vanadium-titanium-magnetite raw ore is separated through ore dressing, about 54% of TiO ₂ enters the iron ore concentrate. After smelting in the blast furnace, almost all of the TiO ₂ enters the slag phase, forming a high concentration of 20-24% TiO ₂ Slag; In addition, due to the high content of impurities such as S, Si, and Al in the iron concentrate, the above reasons not only lead to low utilization coefficient of smelting blast furnace, high energy consumption, waste of titanium resources, but also large amount of slag and serious environmental pollution.

CN2011100879566 discloses "a method for beneficiating ilmenite", which is a method for obtaining titanium concentrate and iron concentrate by magnetically separating vanadium-titanium magnetite raw ore through grinding, alkali leaching pretreatment, filtration, and regrinding. In this method, the vanadium-titanium magnetite raw ore containing 32.16% iron and 12.11% TiO ₂ is processed through grinding, alkali leaching pretreatment, filtration, and magnetic separation after regrinding to form iron concentrate containing 59.30% iron and iron containing TiO ₂ 20.15% titanium concentrate. Since this method is aimed at raw ilmenite ore, which contains high gangue minerals such as SiO ₂ , Al ₂ O ₃ , CaO, and MgO, the alkaline leaching process will preferentially occur on minerals such as SiO ₂ , Al ₂ O ₃ , etc. Alkaline leaching compounds similar to titanium are formed during the alkaline leaching process. The amount of NaOH alkali consumed by alkaline leaching of ilmenite raw ore is 469Kg/t raw ore, which is high in cost; It is very difficult to achieve effective separation of silicon compounds formed after alkali leaching of ore minerals in subsequent magnetic separation, which also restricts the improvement of iron concentrate grade and titanium concentrate grade after alkali leaching of ilmenite raw ore. At the same time, the method uses two grinding processes to change the physical and chemical properties of the mineral surface, which increases the complexity and process cost of the method. In short, the process of this method is complicated, and the alkali consumption is large and the cost is high during the treatment process; at the same time, it is impossible to obtain higher-grade iron ore concentrates and titanium concentrates.

CN201310183580.8 discloses "a method for wet treatment of vanadium-titanium iron concentrate to prepare titanium liquid", and proposes a method for separating ferrotitanium by washing with hydrochloric acid. The invention is a method for wet treatment of vanadium-titanium magnetite concentrate to prepare titanium liquid, including hydrochloric acid leaching of vanadium-titanium magnetite concentrate, molten salt reaction, re-pickling, sulfuric acid acid dissolution, filtration and other processes to obtain titanium liquid. It is aimed at extracting titanium concentrate. The process is complicated. In the hydrochloric acid leaching process, hydrochloric acid needs to react with iron and vanadium to dissolve into the filtrate, which consumes a large amount of hydrochloric acid and is costly. At the same time, NaOH is used to react with titanium and silicon in the molten salt process. Consume alkali. In addition, because hydrochloric acid is used in the leaching process of this method, the chloride ions in the hydrochloric acid corrode the equipment greatly, which is not easy for industrial production. The method is mainly applicable to the recovery and utilization of titanium in low-vanadium-depleted titanium magnetite concentrate with high vanadium and low iron content.

Contents of the invention

In order to overcome the deficiencies of the above-mentioned beneficiation methods, the technical problem to be solved by the present invention is to provide a low cost, high recovery quality and efficiency, simple process, and good operability to utilize alkali The method of leaching, pickling, re-election and re-selection of vanadium-titanium magnetite concentrate realizes efficient separation of titanium and iron in vanadium-titanium magnetite concentrate, improves the iron grade before entering the furnace, and reduces the amount of TiO ₂ , S, and Si entering the blast furnace. , Al and other impurities, improve the blast furnace utilization factor, reduce the discharge of blast furnace slag, reduce the cost of ironmaking, and at the same time improve the comprehensive utilization rate of TiO ₂ resources and reduce environmental pollution.

In order to realize the purpose of the present invention, technical scheme of the present invention is achieved like this:

A method for re-election of vanadium-titanium magnetite concentrate utilizing alkali leaching, pickling and gravity separation of the present invention is characterized in that it comprises the following steps:

1) Alkaline leaching

The TF _e content ranges from 50% to 55%, the _TiO2 content ranges from 10% to 15%, the _SiO2 content ranges from 3% to 6%, _{the Al2O3} content ranges from 3% to 6%, and the S content > 0.5%. The vanadium-titanium magnetite concentrate is placed in an alkali solution with a mass concentration of 5% to 52%, and the alkali leaching reaction is carried out at a temperature of 280°C to 370°C for 0.5 to 5 hours, and the reactant is filtered to obtain the filtrate and alkali leaching Filter cake A, described filtrate feeds recovery treatment system;

2) pickling

Add water to the alkali leaching filter cake A in step 1) to make a slurry with a solid-to-liquid mass ratio of 1:1-10, and then place it in _{a H2SO4} solution with a mass concentration of 1%-10%, at 50-90°C pickling under conditions for 5 to 60 minutes, and filtering the pickling reactants to obtain the filtrate and acid leaching filter cake B, and the filtrate is fed into the recovery treatment system;

3) re-election

Add water to the acid leaching filter cake B in step 2) to make a pulp with a mass concentration of 35% to 40% and carry out gravity separation to obtain TFe content in the range of 65% to 68% iron concentrate and _TiO in the range of 55% to 40%. Final tailings D with 80% titanium concentrate and 57-61% _SiO2 content.

The alkali solution is any one of NaOH or KOH aqueous solution, NaOH and KOH mixed aqueous solution.

The reselection uses Meter spiral chute for re-election.

The advantages of the present invention are:

The method of the present invention comprehensively uses the methods of alkali leaching, pickling and gravity separation to process the vanadium-titanium magnetite concentrate, and realizes the efficient separation of titanium and iron in the vanadium-titanium magnetite concentrate; at the same time, the S content in the separated iron concentrate is greatly reduced, From above 0.50% to less than 0.10%, _SiO2 content from 3% _to 6% to below 3%, _Al2O3 content from 3% to 6% to below 3%, creating a better environment for subsequent smelting condition.

The alkaline leaching process chemically reacts Ti, S, Si, Al and other elements in the vanadium-titanium magnetite concentrate to form corresponding salts. Different from vanadium-titanium magnetite concentrate, the content of SiO ₂ (>20%) _and Al ₂ O ₃ (>7%) in ilmenite raw ore is much higher than that of vanadium-titanium magnetite concentrate (<6 %) and Al ₂ O ₃ content (<6%), in the process of alkali leaching ilmenite ore, since the alkali leaching process will preferentially occur on SiO ₂ , Al ₂ O ₃ and other minerals, the alkali leaching vanadium-titanium magnet The concentrated ore uses less alkali than the alkaline leached ilmenite raw ore, and the effect is better. For example, when using NaOH alkali leaching, the amount of alkali consumed by the present invention is less than 100kg/t concentrate, which is more than 4.6 times lower than the amount of alkali consumed by alkali leaching raw ore of 469kg/t raw ore.

The pickling process effectively dissolves the oxo acid salts and sulfides such as Ti, Si, Al after alkali leaching, and dissociates them from the iron concentrate. In addition, since the present invention uses sulfuric acid for pickling, the reaction conditions are mild, the equipment is less corroded, the cost is low, and it is more favorable for industrialized production.

Coupled with re-election, the grade of iron concentrate is increased from 50% to 55% to 65% to 68%. At the same time, the content of S in iron concentrate is less than 0.1%, and the content of SiO ₂ and Al ₂ O ₃ is less than 3%. The TiO ₂ content is reduced from 12.91% to less than 6%; at the same time, titanium concentrates with a TiO ₂ content of 55% to 80% can also be obtained. This method realizes the effective separation of titanium and iron, reduces the content of impurities such as TiO ₂ , S, Si, and Al entering the blast furnace, improves the utilization factor of the blast furnace, reduces the discharge of blast furnace slag, reduces the cost of ironmaking, and at the same time increases the amount of titanium Comprehensive resource utilization.

Description of drawings

Fig. 1 is a process flow diagram of the present invention.

Fig. 2 is the flow chart of the present invention adopting two-stage re-election process.

Detailed ways

The specific embodiment of the present invention will be further described below in conjunction with accompanying drawing:

Example 1:

As shown in Figure 1.

1) Alkaline leaching

The vanadium-titanium magnetite concentrate with TFe content of 50.5%, _TiO2 content of 14.8%, _SiO2 content of 3.65%, _Al2O3 content of _4.41 %, and S content of 0.56% was placed in NaOH with a mass concentration of 30%. In the alkaline solution, the alkali leaching reaction was carried out at a temperature of 300° C. for 4.5 hours, and the reactants were filtered to obtain the filtrate and the alkali leaching filter cake A. The NaOH consumption was 81 kg/t to feed the ore, and the filtrate was fed to the recovery treatment system. Its chemical reaction formula is:

2) pickling

Add water to the alkali leaching filter cake A in step 1) to make a slurry with a mass solid-to-liquid ratio of 1:9, then place it in _H2SO4 with a mass concentration of 5%, pickle at 70°C for 58 minutes _, and pickle The reactants are filtered to obtain filtrate and acid leached filter cake B, and the filtrate is fed into the recovery treatment system, and its chemical reaction formula is:

3) re-election

Add water to the acid leaching filter cake B in step 2) to make the ore slurry with a mass concentration of 41% and feed The spiral chute of rice is carried out gravity separation, obtains gravity separation concentrate C, gravity separation tailings D and gravity separation ore E respectively, and gravity separation concentrate C is that TFe content is the final iron concentrate of 65.7% (SiO ₂ content is 0.56% , Al ₂ O ₃ content is 1.45%, S content is 0.02%), the described gravity separation tailings D is the final tailings with a SiO ₂ content of 60.2%, and the gravity separation E is the final tailings with a TiO ₂ content of 60.8%. Titanium concentrate.

Example 2:

1) Alkaline leaching

The vanadium-titanium magnetite concentrate with TFe content of 54.5%, _TiO2 content of 10.3%, _SiO2 content of 3.55%, _Al2O3 content of _5.43 %, and S content of 0.66% was placed in NaOH with a mass concentration of 20%. In the alkaline solution, the alkali leaching reaction was carried out at a temperature of 350° C. for 2 hours, and the reactants were filtered to obtain the filtrate and the alkali leaching filter cake A. The NaOH consumption was 78 kg/t to feed the ore, and the filtrate was fed to the recovery treatment system. Its chemical reaction formula is with embodiment 1.

2) pickling

Add water to the alkali _leaching filter cake A in step 1) to make a pulp with a mass solid-to-liquid ratio of 1:7, then place it in _H2SO4 with a mass concentration of 7%, pickle at 50°C for 20 minutes, and pickle The reactant is filtered to obtain the filtrate and acid leached filter cake B, and the filtrate is fed into the recovery treatment system, and its chemical reaction formula is the same as in Example 1.

3) re-election

Add water to the acid leaching filter cake B in step 2) to make the ore slurry with a mass concentration of 36% and feed The spiral chute of rice is carried out gravity separation, respectively obtain gravity separation concentrate C, gravity separation tailings D and gravity separation ore E, gravity separation concentrate C is that TFe content is the final iron concentrate of 66.5% (SiO ₂ content is 0.40% , Al ₂ O ₃ content is 1.85%, S content is 0.01%), described gravity separation tailings D is the final tailings with SiO ₂ content of 58.5%, gravity separation E is the final tailings with TiO ₂ content of 76.0% Titanium concentrate.

Example 3:

1) Alkaline leaching

The vanadium-titanium magnetite concentrate with TFe content of 53.0%, _TiO2 content of _12.5 %, _SiO2 content of 3.75%, _Al2O3 content of 5.50%, and S content of 0.86% was placed in NaOH with a mass concentration of 15%. In the alkaline solution, the alkali leaching reaction was carried out at a temperature of 310° C. for 2.5 hours, and the reactant was filtered to obtain the filtrate and the alkali leaching filter cake A. The NaOH consumption was 75 kg/t to feed the ore, and the filtrate was fed to the recovery treatment system. Its chemical reaction formula is with embodiment 1.

2) pickling

Add water to the alkali _leaching filter cake A in step 1) to make a pulp with a mass solid-to-liquid ratio of 1:5, then place it in _H2SO4 with a mass concentration of 6%, pickle at 60°C for 8 minutes, and pickle The reactant is filtered to obtain the filtrate and acid leached filter cake B, and the filtrate is fed into the recovery treatment system, and its chemical reaction formula is the same as in Example 1.

3) re-election

Add water to the acid leached filter cake B in step 2) to make the ore slurry with a mass concentration of 40% and feed The spiral chute of rice is carried out gravity separation, respectively gets gravity separation concentrate C, gravity separation tailings D and gravity separation ore E, and gravity separation concentrate C is that TFe content is the final iron concentrate of 65.9% (SiO ₂ content is 0.45% , Al ₂ O ₃ content is 1.99%, S content is 0.02%), the described gravity separation tailings D is the final tailings with a SiO ₂ content of 59.0%, and the gravity separation E is the final tailings with a TiO ₂ content of 72.3%. Titanium concentrate.

Example 4:

1) Alkaline leaching

The vanadium-titanium magnetite concentrate with TFe content of 52.0%, _TiO2 content of _13.5 %, _SiO2 content of 3.90%, _Al2O3 content of 5.60%, and S content of 0.59% was placed in NaOH with a mass concentration of 9%. In the alkaline solution, the alkali leaching reaction was carried out at a temperature of 370° C. for 35 minutes, and the reactant was filtered to obtain the filtrate and the alkali leaching filter cake A. The NaOH consumption was 80 kg/t to feed the ore, and the filtrate was fed to the recovery treatment system. Its chemical reaction formula is with embodiment 1.

2) pickling

Add water to the alkali leaching filter cake A in step 1) to make a pulp with a mass solid-to-liquid ratio of 1:1.5, then place it in _H2SO4 with a mass concentration of 3%, _pickle at 65°C for 35 minutes, and pickle The reactant is filtered to obtain the filtrate and acid leached filter cake B, and the filtrate is fed into the recovery treatment system, and its chemical reaction formula is the same as in Example 1.

3) re-election

Add water to the acid leached filter cake B in step 2) to make the ore slurry with a mass concentration of 40% and feed The spiral chute of rice is carried out gravity separation, obtains gravity separation concentrate C, gravity separation tailings D and gravity separation ore E respectively, and gravity separation concentrate C is the final iron concentrate that TFe content is 67.9% (SiO ₂ content is 0.31% , Al ₂ O ₃ content is 1.10%, S content is 0.01%), described gravity separation tailings D is the final tailings with SiO ₂ content of 58.5%, gravity separation E is the final tailings with TiO ₂ content of 79.6% Titanium concentrate.

Example 5:

as shown in picture 2.

1) Alkaline leaching

The vanadium-titanium magnetite concentrate with _TFe content of 52.5%, _TiO2 content of _12.8 %, _SiO2 content of 3.85%, _Al2O3 content of 4.60%, and S content of 0.50% was placed in a 38% In the KOH alkali solution, the alkali leaching reaction was carried out at a temperature of 280°C for 4.0 hours, and the reactant was filtered to obtain the filtrate and the alkali leaching filter cake A. The KOH consumption was 95kg/t to feed the ore, and the filtrate was fed to the recovery treatment system , and its chemical reaction formula is:

2) pickling

Add water to the alkali leaching filter cake A in step 1) to make a slurry with a mass solid-to-liquid ratio of 1:3.5, then place it in _H2SO4 with a mass concentration of 9%, pickle at 60°C for ₂₀ minutes, and pickle The reactants are filtered to obtain filtrate and acid leached filter cake B, and the filtrate is fed into the recovery treatment system, and its chemical reaction formula is:

3) re-election

Add water to the acid leaching filter cake B in step 2) to make the ore slurry with a mass concentration of 36% and feed A section of spiral chute of 1 m is used for roughing to obtain roughing concentrate C1, roughing tailings D1 and roughing ore E respectively, and adding water to the roughing concentrate C1 to make a pulp with a mass concentration of 41% is fed into the The second section of the spiral chute is used for refining, and the selected concentrate C2 and the selected tailings D2 are obtained respectively. The selected tailings D2 returns to the first section of the spiral chute, and the selected concentrate C2 is the final iron concentrate with a TFe content of 65.9%. (SiO ₂ content is 0.43%, Al ₂ O ₃ content is 1.65%, S content is 0.02%), described rougher tailings D1 is the final tailings with SiO ₂ content of 59.5%, rougher ore E is TiO ₂ Final titanium concentrate with a content of 71.0%.

Embodiment 6:

1) Alkaline leaching

The vanadium-titanium magnetite concentrate with a TFe content of 53.5%, a TiO ₂ content of 11.8%, a SiO ₂ content of 3.90%, an Al ₂ O ₃ content of 4.70%, and a S content of 0.55% was placed in KOH with a mass concentration of 49%. In the alkaline solution, the alkali leaching reaction was carried out at a temperature of 290° C. for 3.5 hours, and the reactant was filtered to obtain the filtrate and the alkali leaching filter cake A. The KOH consumption was 98 kg/t to feed the ore, and the filtrate was fed to the recovery treatment system. Its chemical reaction formula is with embodiment 5.

2) pickling

Add water to _the alkali leaching filter cake A in step 1) to make a slurry with a mass solid-to-liquid ratio of 1:2, then place it in _H2SO4 with a mass concentration of 1%, pickle at 90°C for 50 minutes, and pickle The reactant is filtered to obtain the filtrate and acid leached filter cake B, and the filtrate is fed into the recovery treatment system, and its chemical reaction formula is the same as in Example 5.

3) re-election

Add water to the acid leaching filter cake B in step 2) to make the ore slurry with a mass concentration of 37% and feed A section of spiral chute of 1 m is used for roughing to obtain roughing concentrate C1, roughing tailings D1 and roughing ore E, and adding water to the roughing concentrate C1 to make a pulp with a mass concentration of 40% is fed into the The second section of the spiral chute is used for refining, and the selected concentrate C2 and the selected tailings D2 are obtained respectively. The selected tailings D2 returns to the first section of the spiral chute, and the selected concentrate C2 is the final iron concentrate with a TFe content of 66.5%. (SiO ₂ content is 0.53%, Al ₂ O ₃ content is 1.86%, S content is 0.01%), described roughing tailings D1 is the final tailings with SiO ₂ content of 57.5%, and rougher ore selection E is TiO ₂ Final titanium concentrate with a content of 73.2%.

Embodiment 7:

1) Alkaline leaching

The vanadium-titanium magnetite concentrate with a TFe content of 52.8%, a _TiO2 content of 11.5%, a _SiO2 content of 3.96%, _{an Al2O3} content of 4.74%, and a S content of 0.57% was placed in a NaOH mass concentration of 20%, In an alkali solution with a KOH mass concentration of 5%, the alkali leaching reaction was carried out at a temperature of 300°C for 1.5 hours, and the reactant was filtered to obtain the filtrate and alkali leaching filter cake A. The NaOH consumption was 60kg/t for ore feeding, and the KOH consumption was 20kg/t feeds ore, and described filtrate feeds into recovery processing system, and its chemical reaction formula is the same as embodiment 1 and embodiment 5.

2) pickling

Add water to the alkali _leaching filter cake A in step 1) to make a slurry with a mass solid-to-liquid ratio of 1:2, then place it in _H2SO4 with a mass concentration of 2%, pickle at 80°C for 40 minutes, and pickle The reactant is filtered to obtain the filtrate and acid leached filter cake B, and the filtrate is fed into the recovery treatment system, and its chemical reaction formula is the same as in Example 1 and Example 5.

3) re-election

Add water to the acid leaching filter cake B in step 2) to make the ore slurry with a mass concentration of 37% and feed A section of spiral chute of 1 m is used for roughing to obtain roughing concentrate C1, roughing tailings D1 and roughing ore E, and adding water to the roughing concentrate C1 to make a pulp with a mass concentration of 40% is fed into the The second section of the spiral chute is used for refining, and the selected concentrate C2 and the selected tailings D2 are respectively obtained. The selected tailings D2 returns to the first section of the spiral chute, and the selected concentrate C2 is the final iron concentrate with a TFe content of 67.8%. (SiO ₂ content is 0.30%, Al ₂ O ₃ content is 1.26%, S content is 0.01%), described rougher tailings D1 is the final tailings with SiO ₂ content of 57.5%, rougher ore E is TiO ₂ Final titanium concentrate with a content of 73.2%.

Claims (3)

1. a method utilizing alkali leaching, pickling and re-election vanadium-titanium magnetite concentrate is characterized in that comprising the steps: 1) Alkaline leaching The TFe content ranges from 50% to 55%, the _TiO2 content ranges from 10% to 15%, the _SiO2 content ranges from 3% to 6%, _{the Al2O3} content ranges from 3% to 6%, and the S content > 0.5%. The vanadium-titanium magnetite concentrate is placed in an alkali solution with a mass concentration of 5% to 52%, and the alkali leaching reaction is carried out at a temperature of 280°C to 370°C for 0.5 to 5 hours, and the reactant is filtered to obtain the filtrate and alkali leaching Cake A, described filtrate feeds recovery treatment system; 2) pickling Add water to the alkali leaching filter cake A in step 1) to make a slurry with a solid-to-liquid mass ratio of 1:1 to 10, and then place it in _{a H2SO4} solution with a mass concentration of 1% to 10%, at 50°C to 90°C pickling at ℃ for 5-60 minutes, filtering the pickling reactants to obtain the filtrate and acid leaching filter cake B, and feeding the filtrate into the recovery treatment system; 3) re-election Add water to the acid leaching filter cake B in step 2) to make a pulp with a mass concentration of 35% to 40% for re-election, and obtain iron concentrate C with a TFe content of 65% to 68% and _{a TiO} content of 55% ~80% titanium concentrate E and final tailings D with 57~61% _SiO2 content. 2. the method for utilizing alkali leaching, pickling and gravity re-election vanadium-titanium magnetite concentrate according to claim 1, it is characterized in that described alkali solution is any in NaOH or KOH aqueous solution, NaOH and KOH mixed aqueous solution A sort of. 3. the method for utilizing alkaline leaching according to claim 1, pickling and re-election to re-election vanadium-titanium magnetite concentrate, it is characterized in that described re-election adopts Meter spiral chute for re-election.