CN104962729A - Method for recleaning vanadium-titanium magnetite concentrate through forging, oxidative alkaline leaching and grading - Google Patents

Abstract

The invention relates to a method for recleaning vanadium-titanium magnetite concentrate through forging, oxidative alkaline leaching and grading. The method includes the following steps that CaO is added into the vanadium-titanium magnetite concentrate according to the weight proportion of 1 to 0.1-0.2, and forging is performed at the temperature ranging from 800 DEG C to 1400 DEG C; the forged product A is placed in an alkaline solution with the mass concentration being 5-52%; an oxidizing agent is added, then an alkaline leaching reaction is carried out for 0.5-2.5 hours at the temperature of 220-330 DEG C, and filtered liquid and an alkaline leaching filter cake B are obtained; and the filter cake B is graded and recleaned. The method has the advantages that a compound containing S is oxidized by introducing O2 or H2O2 during oxidative alkaline leaching, the reaction is accelerated, the reaction temperature is lowered, and the reaction time is shortened; besides, iron concentrate with the content of TFe being 62-69% and titanium concentrate with the content of TiO2 being 36-52% are graded, the content of impurities, such as TiO2, S, Si and Al, entering a blast furnace is reduced, the utilization coefficient of the blast furnace is increased, and meanwhile the comprehensive utilization rate of titanium resources is increased.

Description

Calcining, alkali oxide leaching and classification is utilized to select the method for v-ti magnetite concentrate again

Technical field

The present invention relates to a kind of ore-dressing technique of v-ti magnetite concentrate, particularly relate to a kind of method utilizing calcining, alkali oxide leaching and classification to select v-ti magnetite concentrate again.

Background technology

Vanadium titano-magnetite is a kind of complex ore of multiple metallic element, is based on the magnetite of the symbiosis of iron content, vanadium, titanium.And one of v-ti magnetite concentrate product that to be vanadium titano-magnetite obtain through ore dressing, wherein vanadium is composed with isomorph and is stored in titanomagnetite, displacement ferric ion.Titanomagnetite is oikocryst mineral (Fe ₃o ₄) and chadacryst ore deposit [ulvite 2FeOTiO ₂, ilmenite FeOTiO ₂, aluminum-spinel (Mg, Fe) (Al, Fe) ₂o ₄] complex body that formed.Such as, Chinese Panzhihua Region Midi Concentrator v-ti magnetite green ore and the chemistry of the v-ti magnetite concentrate after selecting iron multielement analysis the results are shown in Table 1, and v-ti magnetite green ore and vanadium titano-magnetite concentrate material phase analysis result are respectively in table 2 and table 3.

table 1 Chinese Panzhihua Region Midi Concentrator raw ore and v-ti magnetite concentrate chemistry multielement analysis result

Element	TFe	FeO	mFe	S	Fe 2O 3	TiO 2	V 2O 5
								Raw ore	29.53	21.36	20.20	0.631	17.70	10.54	0.27 8
Concentrate	54.01	32.42	51.16	0.574	40.97	12.67	0.61
								Element	SiO 2	Al 2O 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 2china's Panzhihua Region Midi Concentrator v-ti magnetite green ore titanium, iron chemical phase analysis result

table 3china's Panzhihua Region Midi Concentrator vanadium titano-magnetite concentrate titanium, iron chemical phase analysis result

Vanadium titano-magnetite aboundresources in the world, whole world reserves reach more than 40,000,000,000 tons, and reserves in China reaches 98.3 hundred million tons.In v-ti magnetite ore, iron is mainly composed and is stored in titanomagnetite, the TiO in ore ₂main tax is stored in granular ilmenite and titanomagnetite.Generally, the titanium of about 57% is composed and is stored in titanomagnetite (mFeTiO ₃nFe ₃o ₄) in, the titanium of about 40% is composed and is stored in ilmenite (FeTiO ₃) in, because vanadium titano-magnetite ore composition is complicated, character is special, and thus the comprehensive utilization of this kind of ore is the international a great problem always thoroughly do not solved.This occurrence characteristics of vanadium titano-magnetite mineral determines the effective separation adopting physical concentration method cannot realize titanium, iron from the source of ore, cause v-ti magnetite ore after physical concentration, iron concentrate grade low (TFe<55%), the titanium in iron ore concentrate enters blast furnace slag (TiO completely at iron manufacturing process ₂content reaches more than 22%) form vitreum, TiO ₂lose activity and cannot economic recovery, meanwhile, titanium recovery rate is low only has 18%.Therefore sort titanium iron ore by the beneficiation method of physics and greatly reduce the value that titanium and iron utilizes separately.

China is first country comprehensively extracting iron, vanadium, titanium with technical scale from complicated vanadium titano-magnetite in the world, but due to general physical method fundamentally can not change iron, the tax of the fine and close symbiosis of titanium deposits characteristic, therefore, adopt the physical concentration methods such as common gravity separation method, magnetic method, flotation process to carry out titanium, iron is separated, efficiency is low, is difficult to select of high grade and the ilmenite concentrate that impurity is few or iron ore concentrate; Meanwhile, TiO ₂organic efficiency is not high, v-ti magnetite green ore after Mineral separation, the TiO of about 54% ₂enter iron ore concentrate, these TiO ₂after blast-furnace smelting, almost all enter slag phase, form TiO ₂the blast furnace slag of content 20 ~ 24%; In addition, because the foreign matter contents such as S, Si, the Al in iron ore concentrate are also too high, above-mentioned reason not only causes that steelmaking furnace utilization coefficient is low, energy consumption is large, titanium resource waste, and amount of slag is large, environmental pollution is serious.

CN2011100879566 discloses " a kind of beneficiation method of ilmenite ", is the magnetic separation after ore grinding, alkaline pretreatment, filtration, again ore grinding of v-ti magnetite green ore is obtained the method for ilmenite concentrate and iron ore concentrate.The method is by iron content 32.16% with containing TiO ₂the v-ti magnetite green ore of 12.11%, by magnetic separation process after ore grinding, alkaline pretreatment, filtration, again ore grinding, defines iron content 59.30% iron ore concentrate and contains TiO ₂the ilmenite concentrate of 20.15%.Because the method is for ilmenite raw ore, raw ore SiO ₂, Al ₂o ₃, the gangue mineral content such as CaO, MgO is high, the process of alkali leaching preferentially will occur in SiO ₂, Al ₂o ₃with it mineral, define the alkali leaching rear compound similar to titanium in the dipped journey of alkali, the NaOH alkali number of alkali leaching ferrotianium raw ore consumption is 469Kg/t raw ore, and cost is high; And the titanium compound formed after the leaching of ferrotianium raw ore alkali, the compound of the silicon formed after soaking with the gangue mineral alkali such as quartz, it is very difficult for wanting to realize effectively being separated in follow-up magnetic separation, and this also constrains the raising of the rear iron concentrate grade of ferrotianium raw ore alkali leaching and ilmenite concentrate grade.Meanwhile, the method adopts twice grinding process to change mineral surface physicochemical property, adds complexity and the process cost of the method.In a word, by this kind of procedure complexity, and in treating processes, quantity of alkali consumption is large, cost is high; Meanwhile, more high-grade iron ore concentrate and ilmenite concentrate cannot be obtained.

CN201310183580.8 discloses " a kind of wet processing sefstromite concentrate prepares the method for titanium liquid ", proposes the method with salt pickling separating titanium iron.This invention is the method that wet processing v-ti magnetite concentrate prepares titanium liquid, comprise v-ti magnetite concentrate hydrochloric acid leaching, molten salt react ion, again pickling, sulfuric acid solution, filtration etc. and obtain the processes such as titanium liquid, the method is mainly for extraction ilmenite concentrate, its complex technical process, need in hydrochloric acid leaching process to react with hydrochloric acid and iron and vanadium to dissolve in filtrate, consume a large amount of hydrochloric acid, cost is high; Meanwhile, NaOH and titanium and pasc reaction is used to consume alkali in fused salt process.In addition, owing to employing hydrochloric acid in the method leaching process, in hydrochloric acid, chlorion is large to equipment corrosion, not easily suitability for industrialized production.The method is mainly applicable to the recycling of titanium in the low poor v-ti magnetite concentrate of high vanadium low iron content.

CN201410164285.2 discloses one " utilization calcining, the method that alkali soaks, v-ti magnetite concentrate is selected in classification again ", the ratio of v-ti magnetite concentrate 1:0.1 ~ 0.2 is by weight added CaO by this invention, then at the temperature of 800 DEG C ~ 1400 DEG C, calcining 20 ~ 60 minutes is carried out, again calcination product is placed in the leaching of alkaline solution alkali, then feed swirler after alkali leaching cheese being become ore pulp and carry out classification, obtaining TFe content is respectively 60% ~ 68% iron ore concentrate, TiO ₂content is 35% ~ 50% ilmenite concentrate.The method achieve and efficiently sort v-ti magnetite concentrate, but adopt alkali leaching due to simple in reaction, react 0.5 ~ 5 hour at 300 ~ 370 DEG C of temperature, chemical reaction temperature is higher, and the time is longer, and SiO after reaction ₂and TiO ₂content is up to 3%, and foreign matter content is higher, causes the capacity factor of a blast furnace to reduce, adds ironmaking cost; In this inventive method, alkaline consumption is higher, and alkali leaching product sodium titanate or the productive rate of potassium titanate are less than 80kg/T raw ore, sodium titanate or the lower titanium resource utilization ratio that causes of potassium titanate productive rate not high.

Summary of the invention

In order to overcome the deficiency of above-mentioned beneficiation method, technical problem to be solved by this invention is on the basis that physics and chemistry beneficiation method effectively combines, there is provided a kind of cost low, reclaim the method that v-ti magnetite concentrate is selected in quality and the high and utilization calcining of good operability of efficiency, alkali oxide leaching, classification again, achieve and high efficiency separation is carried out to titanium, iron in v-ti magnetite concentrate, improve into stokehold Iron grade, reduce and enter blast furnace TiO ₂, the impurity such as S, Si, Al content, improve the capacity factor of a blast furnace, reduce the quantity discharged of blast furnace slag, reduce ironmaking cost, improve TiO ₂comprehensive resource utilization rate, reduces NaOH or KOH consumption simultaneously, decreases environmental pollution.

In order to realize object of the present invention, technical scheme of the present invention is achieved in that

Of the present inventionly a kind ofly utilize calcining, alkali oxide leaching, classification to select the method for v-ti magnetite concentrate again, it is characterized in that comprising the steps:

1) calcine

Be 50% ~ 55%, TiO by TFe content range ₂content range is 10% ~ 15%, SiO ₂content is 3% ~ 6%, Al ₂o ₃content is 3% ~ 6%, the ratio of the v-ti magnetite concentrate of S content >0.5% 1:0.1 ~ 0.2 by weight adds CaO, at the temperature of 800 DEG C ~ 1400 DEG C, carry out calcining 20 ~ 60 minutes, forms calcination product A;

2) alkali oxide leaching

Calcination product A in step 1) is placed in the alkaline solution that mass concentration is 5% ~ 52%, adds oxygenant, then at the temperature of 220 DEG C ~ 330 DEG C, alkali soaks reaction 0.5 ~ 2 hour, and obtain filtrate and alkali leaching cake B, described filtrate feeds recovery and processing system;

3) classification

By step 2) in alkali leaching cake B add water, form the ore pulp of mass concentration 20% ~ 25% and feed swirler and carry out classification, classification goes out sand setting C and overflow D, described sand setting C to be TFe content range be 62% ~ 69% final iron ore concentrate, described overflow D simmer down to TiO ₂content range is the ilmenite concentrate of 36% ~ 52%.

Described alkaline solution is any one in the NaOH aqueous solution, the KOH aqueous solution or NaOH and KOH mixed aqueous solution.

Described oxygenant is O ₂or H ₂o ₂, described O ₂add-on is 20 ~ 120psi, H ₂o ₂add-on is 50 ~ 200kg/t _{to ore deposit}.

Advantage of the present invention is:

Calcination utilizes CaO part to replace alkali lye consumption in the dipped journey of alkali, decreases the consumption 20% ~ 30% of NaOH or KOH in follow-up alkali leaching operation; Because CaO price is NaOH price 1/5 ~ 1/6, be 1/20 of KOH price, therefore greatly can reduce production cost.

The process of alkali oxide leaching has carried out chemical reaction to elements such as Ti, S, Si, Al in v-ti magnetite concentrate, defines corresponding salt, makes the iron in v-ti magnetite concentrate change the form of ferric oxide into.With v-ti magnetite concentrate unlike, SiO in ilmenite raw ore ₂and Al ₂o ₃content far away higher than SiO in v-ti magnetite concentrate ₂and Al ₂o ₃content, wherein SiO in ilmenite raw ore ₂>20%, Al ₂o ₃>7%, SiO in v-ti magnetite concentrate ₂<6%, Al ₂o ₃<6%.In alkali leaching ilmenite raw ore process, because the process of alkali leaching preferentially will occur in SiO ₂, Al ₂o ₃deng on mineral, alkali is made to soak v-ti magnetite concentrate more less than alkali leaching ilmenite raw ore alkali consumption, simultaneously O ₂introducing make containing S compound oxidation, oxidized FeTiO ₃, accelerate reaction, reduce temperature of reaction, shorten the reaction times, better effects if, greatly reduce energy consumption and facility investment.Such as, after calcining, when soaking with NaOH alkali oxide, the alkali number that the present invention consumes is less than 50kg/t concentrate, reduces more than 9 times than the alkali number 469kg/t raw ore of alkali leaching raw ore consumption.The alkali number consumed than the alkali leaching not passing into oxygen reduces 10kg/t concentrate; O ₂introducing alkali is soaked temperature of reaction is minimum is down to 220 DEG C, the reaction times is less than 2 hours.

In addition, in the method, the reaction product of alkali oxide leaching is sodium titanate or potassium titanate, the productive rate of sodium titanate or potassium titanate is greater than 100kg/T raw ore, sodium titanate or potassium titanate are present in final product ilmenite concentrate, a large amount of whisker is had, as shown in Figure 2,3, 4 by the microstructure of scanning electron microscopic observation ilmenite concentrate is known.The whisker of potassium titanate and sodium titanate has excellent character and applies widely, and main practical feature and performance are: have excellent micro-enhancing and filling capacity; The wear-resisting of excellence undermines Frictional Slipping performance; Excellent surface smoothness and high dimensional precision and stability; Processability is good, to processing units and die wear little; Market price 6.5 ~ 150,000/the ton of potassium titanate crystal whisker.Potassium titanate and sodium titanate are also widely used in flux-cored wire, stainless steel electrode, low-hydrogen electrode, AC/DC welding rod.As welding rod additive, the market price 1.8 ten thousand/ton of sodium titanate, the method effectively improves TiO ₂comprehensive resource utilization rate.

Swirler presses granularity and the gravity grading of mineral, and the titanium compound generated after alkali oxide leaching is than the fine size of iron mineral, and proportion is little, and the difference of specific gravity of titanium, iron is comparatively large, achieves effective separation of titanium, iron.Add that classification makes iron concentrate grade bring up to 62% ~ 69% by 50% ~ 55%, in isolated iron ore concentrate, S content significantly reduces simultaneously, is down to is less than 0.10%, SiO by more than 0.50% ₂content is down to less than 1%, Al by 3% ~ 6% ₂o ₃content is down to less than 1.8%, TiO by 3% ~ 6% ₂content is down to less than 6% by more than 12%, meanwhile, can also obtain TiO ₂content is the ilmenite concentrate of 36% ~ 52%.

Integrated use calcining of the present invention, the method that alkali oxide soaks, v-ti magnetite concentrate is selected in classification again, achieve titanium in v-ti magnetite concentrate, iron high efficiency separation, decrease the TiO entering blast furnace ₂, the impurity such as S, Si, Al content, improve the capacity factor of a blast furnace, reduce the quantity discharged of blast furnace slag, reduce ironmaking cost, for subsequent smelting creates better condition, improve the comprehensive utilization ratio of titanium resource simultaneously.

Accompanying drawing explanation

Fig. 1 is present invention process schema.

Fig. 2 is the microstructure photograph (X10000) of the scanning electron microscopic observation ilmenite concentrate of ilmenite concentrate.

Fig. 3 is the microstructure photograph (X5000) of the scanning electron microscopic observation ilmenite concentrate of ilmenite concentrate.

Fig. 4 is the microstructure photograph (X2000) of the scanning electron microscopic observation ilmenite concentrate of ilmenite concentrate.

Embodiment

Below in conjunction with accompanying drawing, the specific embodiment of the present invention is described further:

As shown in Figure 1.

Embodiment 1:

1) calcine

Be 50.3%, TiO by TFe content ₂content is 14.6%, SiO ₂content is 3.69%, Al ₂o ₃content is 4.47%, the v-ti magnetite concentrate of S content 0.59%, and the ratio of 1:0.1 adds CaO by weight, at the temperature of 1200 DEG C, carry out calcining 30 minutes, and form calcination product A, its chemical equation is:

CaO+ TiO ₂ CaTiO ₃

2) alkali oxide leaching

Calcination product A in step 1) is placed in the NaOH alkaline solution that mass concentration is 18%, passes into the O of 21psi ₂, then at the temperature of 220 DEG C, alkali soaks reaction 1.0 hours, and filtered by reactant, obtain filtrate and alkali leaching cake B, NaOH consumption 47.2 kg/t is to ore deposit, and described filtrate feeds recovery and processing system, and its chemical equation is:

4mFeTiO ₃+8NaOH +mO ₂ 2mFe ₂O ₃↓+4Na ₂O·(TiO ₂) _m↓+4H ₂O m≥1

pFe ₃O ₄·q（FeO·TiO ₂) +2rNaOH pFe ₃O ₄↓+qFeO↓+ (Na ₂O) _r·(TiO ₂) _q↓+rH ₂O

Al ₂O ₃+2NaOH 2NaAlO ₂+ H ₂O

tSiO ₂+2NaOH Na ₂O·(SiO ₂) _t↓+ H ₂O

3FeS ₂+6NaOH 3FeS↓+Na ₂SO ₃+2Na ₂S+3H ₂O

4FeS ₂+ 11O ₂ 2Fe ₂O ₃ + 8SO ₂

4FeO+O ₂ 2Fe ₂O ₃

2SO ₂+O ₂+4NaOH 2Na ₂SO ₄+ 2H ₂O

3) classification

By step 2) in alkali leaching cake B add water, form the ore pulp of mass concentration 20% and feed swirler and carry out classification, classification goes out sand setting C and overflow D, and sand setting C is the final iron ore concentrate of TFe content 62.8%, wherein SiO ₂content is 0.89%, Al ₂o ₃content is 1.35%, S content is 0.02%; Overflow D simmer down to TiO ₂content is the final ilmenite concentrate of 41.2%.

In the method, the reaction product of alkali oxide leaching is sodium titanate, and the productive rate of sodium titanate is greater than 100kg/T raw ore, and sodium titanate is present in final product ilmenite concentrate, has a large amount of whisker, as shown in Figure 2 by the microstructure of scanning electron microscopic observation ilmenite concentrate is known.

Embodiment 2:

1) calcine

Be 53.5%, TiO by TFe content ₂content is 11.3%, SiO ₂content is 3.59%, Al ₂o ₃content is 5.45%, the v-ti magnetite concentrate of S content 0.74%, and the ratio of 1:0.11 adds CaO by weight, at the temperature of 1000 DEG C, carry out calcining 45 minutes, and form calcination product A, its chemical equation is with embodiment 1.

2) alkali oxide leaching

Calcination product A in step 1) is placed in the NaOH alkaline solution that mass concentration is 10%, passes into the O of 46psi ₂, then at the temperature of 280 DEG C, alkali soaks reaction 1.5 hours, and filtered by reactant, obtain filtrate and alkali leaching cake B, NaOH consumption 45.3 kg/t is to ore deposit, and described filtrate feeds recovery and processing system, and its chemical equation is with embodiment 1.

3) classification

By step 2) in alkali leaching cake B add water, form the ore pulp of mass concentration 21% and feed swirler and carry out classification, classification goes out sand setting C and overflow D, and sand setting C is the final iron ore concentrate of TFe content 65.4%, wherein SiO ₂content is 0.61%, Al ₂o ₃content is 1.33%, S content is 0.02%; Overflow D simmer down to TiO ₂content is the final ilmenite concentrate of 36.1%.

In the method, the reaction product of alkali oxide leaching is sodium titanate, and the micro-structural feature of ilmenite concentrate as shown in Figure 2.

Embodiment 3:

1) calcine

Be 51.2%, TiO by TFe content ₂content is 13.8%, SiO ₂content is 3.75%, Al ₂o ₃content is 5.18%, the v-ti magnetite concentrate of S content 0.63%, and the ratio of 1:0.11 adds CaO by weight, at the temperature of 900 DEG C, carry out calcining 50 minutes, and form calcination product A, its chemical equation is with embodiment 1.

2) alkali oxide leaching

Calcination product A in step 1) is placed in the NaOH alkaline solution that mass concentration is 28%, adds 57kg/t _{to ore deposit}h ₂o ₂, then at the temperature of 240 DEG C, alkali soaks reaction 75 minutes, and filtered by reactant, obtain filtrate and alkali leaching cake B, NaOH consumption 42.4kg/t is to ore deposit, and described filtrate feeds recovery and processing system, and its chemical equation is:

2mFeTiO ₃+4NaOH+mH ₂O ₂ mFe ₂O ₃↓+2Na ₂O·(TiO ₂) _m↓+(m+2)H ₂O m≥1

pFe ₃O ₄·q（FeO·TiO ₂) +2rNaOH pFe ₃O ₄↓+qFeO↓+ (Na ₂O) _r·(TiO ₂) _q↓+rH ₂O

Al ₂O ₃+2NaOH 2NaAlO ₂+ H ₂O

tSiO ₂+2NaOH Na ₂O·(SiO ₂) _t↓+ H ₂O

3FeS ₂+6NaOH 3FeS↓+Na ₂SO ₃+2Na ₂S+3H ₂O

2FeS ₂+ 11H ₂O ₂ Fe ₂O ₃ +4SO ₂+ 11H ₂O

2FeO+H ₂O ₂ Fe ₂O ₃+ H ₂O

SO ₂+H ₂O ₂+2NaOH Na ₂SO ₄+ 2H ₂O

3) classification

By step 2) in alkali leaching cake B add water, form the ore pulp of mass concentration 22% and feed swirler and carry out classification, classification goes out sand setting C and overflow D, and sand setting C is the final iron ore concentrate of TFe content 64.7%, wherein SiO ₂content is 0.54%, Al ₂o ₃content is 1.40%, S content is 0.02%; Overflow D simmer down to TiO ₂content is the final ilmenite concentrate of 37.9%.

In the method, the reaction product of alkali oxide leaching is sodium titanate, and the micro-structural feature of ilmenite concentrate as shown in Figure 2.

Embodiment 4:

1) calcine

Be 54.8%, TiO by TFe content ₂content is 10.5%, SiO ₂content is 3.56%, Al ₂o ₃content is 5.17%, the v-ti magnetite concentrate of S content 0.68%, and the ratio of 1:0.12 adds CaO by weight, at the temperature of 1300 DEG C, carry out calcining 35 minutes, and form calcination product A, its chemical equation is with embodiment 1.

2) alkali oxide leaching

Calcination product A in step 1) is placed in the NaOH alkaline solution that mass concentration is 49%, passes into the O of 118psi ₂, then at the temperature of 330 DEG C, alkali soaks reaction 45 minutes, and filtered by reactant, obtain filtrate and alkali leaching cake B, NaOH consumption 46.5kg/t is to ore deposit, and described filtrate feeds recovery and processing system, and its chemical equation is with embodiment 1.

3) classification

By step 2) in alkali leaching cake B add water, form the ore pulp of mass concentration 23% and feed swirler and carry out classification, classification goes out sand setting C and overflow D, and sand setting C is the final iron ore concentrate of TFe content 68.5%, wherein SiO ₂content is 0.57%, Al ₂o ₃content is 1.36%, S content is 0.01%; Overflow D simmer down to TiO ₂content is the final ilmenite concentrate of 48.5%.

In the method, the reaction product of alkali oxide leaching is sodium titanate, and the micro-structural feature of ilmenite concentrate as shown in Figure 2.

Embodiment 5:

1) calcine

Be 52.8%, TiO by TFe content ₂content is 12.9%, SiO ₂content is 3.62%, Al ₂o ₃content is 5.31%, the v-ti magnetite concentrate of S content 0.77%, and the ratio of 1:0.15 adds CaO by weight, at the temperature of 1400 DEG C, carry out calcining 20 minutes, and form calcination product A, its chemical equation is with embodiment 1.

2) alkali oxide leaching

Calcination product A in step 1) is placed in the KOH alkaline solution that mass concentration is 35%, passes into the O of 87psi ₂, then at the temperature of 260 DEG C, alkali soaks reaction 1.0 hours, and filtered by reactant, obtain filtrate and alkali leaching cake B, KOH consumption 44.0kg/t is to ore deposit, and described filtrate feeds recovery and processing system, and its chemical equation is:

4mFeTiO ₃+8KOH+mO ₂ 2mFe ₂O ₃↓+4K ₂O·(TiO ₂) _m↓+4H ₂O m≥1

pFe ₃O ₄·q（FeO·TiO ₂) +2rKOH pFe ₃O ₄↓+qFeO↓+ (K ₂O) _r·(TiO ₂) _q↓+rH ₂O

Al ₂O ₃+2KOH 2KAlO ₂+ H ₂O

tSiO ₂+2KOH K ₂O·（SiO ₂） _t↓+ H ₂O

3FeS ₂+6KOH 3FeS↓+K ₂SO ₃+2K ₂S+3H ₂O

4FeS ₂+ 11O ₂ 2Fe ₂O ₃ + 8SO ₂

4FeO+O ₂ 2Fe ₂O ₃

2SO ₂+O ₂+4KOH 2K ₂SO ₄+ 2H ₂O

3) classification

By step 2) in alkali leaching cake B add water, form the ore pulp of mass concentration 24% and feed swirler and carry out classification, classification goes out sand setting C and overflow D, and sand setting C is the final iron ore concentrate of TFe content 66.9%, wherein SiO ₂content is 0.60%, Al ₂o ₃content is 1.32%, S content is 0.01%; Overflow D simmer down to TiO ₂content is the final ilmenite concentrate of 46.5%.

In the method, the reaction product of alkali oxide leaching is potassium titanate, and the productive rate of potassium titanate is greater than 100kg/T raw ore, and potassium titanate is present in final product ilmenite concentrate, has a large amount of whisker, as shown in Figure 3 by the microstructure of scanning electron microscopic observation ilmenite concentrate is known.

Embodiment 6:

1) calcine

Be 53.2%, TiO by TFe content ₂content is 11.8%, SiO ₂content is 3.99%, Al ₂o ₃content is 4.42%, the v-ti magnetite concentrate of S content 0.57%, and the ratio of 1:0.18 adds CaO by weight, at the temperature of 800 DEG C, carry out calcining 60 minutes, and form calcination product A, its chemical equation is with embodiment 1.

2) alkali oxide leaching

Calcination product A in step 1) is placed in the KOH alkaline solution that mass concentration is 25%, adds 98kg/t _{to ore deposit}h ₂o ₂, then at the temperature of 310 DEG C, alkali soaks reaction 100 minutes, and filtered by reactant, obtain filtrate and alkali leaching cake B, KOH consumption 37kg/t is to ore deposit, and described filtrate feeds recovery and processing system, and its chemical equation is:

2mFeTiO ₃+4KOH+mH ₂O ₂ mFe ₂O ₃↓+2K ₂O·(TiO ₂) _m↓+(m+2)H ₂O m≥1

pFe ₃O ₄·q（FeO·TiO ₂) +2rKOH pFe ₃O ₄↓+qFeO↓+ (K ₂O) _r·(TiO ₂) _q↓+rH ₂O

Al ₂O ₃+2KOH 2KAlO ₂+ H ₂O

tSiO ₂+2KOH K ₂O·(SiO ₂) _t↓+ H ₂O

3FeS ₂+6KOH 3FeS↓+K ₂SO ₃+2K ₂S+3H ₂O

2FeS ₂+ 11H ₂O ₂ Fe ₂O ₃ +4SO ₂+ 11H ₂O

2FeO+H ₂O ₂ Fe ₂O ₃+ H ₂O

SO ₂+H ₂O ₂+2KOH K ₂SO ₄+ 2H ₂O

3) classification

By step 2) in alkali leaching cake B add water, form the ore pulp of mass concentration 25% and feed swirler and carry out classification, classification goes out sand setting C and overflow D, and sand setting C is the final iron ore concentrate of TFe content 67.8%, wherein SiO ₂content is 0.37%, Al ₂o ₃content is 1.30%, S content is 0.01%; Overflow D simmer down to TiO ₂content is the final ilmenite concentrate of 51.4%.

In the method, the reaction product of alkali oxide leaching is potassium titanate, and the micro-structural feature of ilmenite concentrate as shown in Figure 3.

Embodiment 7:

1) calcine

Be 54.0%, TiO by TFe content ₂content is 11.1%, SiO ₂content is 3.87%, Al ₂o ₃content is 4.69%, the v-ti magnetite concentrate of S content 0.54%, and the ratio of 1:0.2 adds CaO by weight, at the temperature of 1150 DEG C, carry out calcining 40 minutes, and form calcination product A, its chemical equation is with embodiment 1.

2) alkali oxide leaching

Calcination product A in step 1) is placed in NaOH mass concentration be 20% and KOH mass concentration be the mixed ammonium/alkali solutions of 6%, pass into 106psiO ₂, then at the temperature of 300 DEG C, alkali soaks reaction 2.0 hours, is filtered by reactant, obtain filtrate and alkali leaching cake B, NaOH consumption 15kg/t is to ore deposit, KOH consumption 20kg/t to ore deposit, and described filtrate feeds recovery and processing system, and its chemical equation is with embodiment 1 and embodiment 5.

3) classification

By step 2) in alkali leaching cake B add water, form the ore pulp of mass concentration 23% and feed swirler and carry out classification, classification goes out sand setting C and overflow D, and sand setting C is the final iron ore concentrate of TFe content 68.0%, wherein SiO ₂content is 0.45%, Al ₂o ₃content is 1.07%, S content is 0.01%; Overflow D simmer down to TiO ₂content is the final ilmenite concentrate of 48.9%.

In the method, the reaction product of alkali oxide leaching is the mixture of potassium titanate and sodium titanate, the overall yield of potassium titanate and sodium titanate is greater than 100kg/T raw ore, potassium titanate and sodium titanate are present in final product ilmenite concentrate, a large amount of whisker is had, as shown in Figure 4 by the microstructure of scanning electron microscopic observation ilmenite concentrate is known.

Embodiment 8:

1) calcine

Be 53.0%, TiO by TFe content ₂content is 11.6%, SiO ₂content is 4.07%, Al ₂o ₃content is 4.89%, the v-ti magnetite concentrate of S content 0.55%, and the ratio of 1:0.15 adds CaO by weight, at the temperature of 1200 DEG C, carry out calcining 40 minutes, and form calcination product A, its chemical equation is with embodiment 1.

2) alkali oxide leaching

Calcination product A in step 1) is placed in NaOH mass concentration be 25% and KOH mass concentration be the mixed ammonium/alkali solutions of 5%, add 192kg/t _{to ore deposit}h ₂o ₂, then at the temperature of 290 DEG C, alkali soaks reaction 2.0 hours, is filtered by reactant, obtain filtrate and alkali leaching cake B, NaOH consumption 16.5kg/t is to ore deposit, KOH consumption 19.2kg/t to ore deposit, and described filtrate feeds recovery and processing system, and its chemical equation is with embodiment 3 and embodiment 6.

3) classification

By step 2) in alkali leaching cake B add water, form the ore pulp of mass concentration 23% and feed swirler and carry out classification, classification goes out sand setting C and overflow D, and sand setting C is the final iron ore concentrate of TFe content 68.5%, wherein SiO ₂content is 0.51%, Al ₂o ₃content is 1.17%, S content is 0.01%; Overflow D simmer down to TiO ₂content is the final ilmenite concentrate of 48.0%.

In the method, the reaction product of alkali oxide leaching is potassium titanate and sodium titanate, and the micro-structural feature of ilmenite concentrate as shown in Figure 4.

Claims (3)

1. utilize calcining, alkali oxide leaching and classification to select a method for v-ti magnetite concentrate again, it is characterized in that comprising the steps:

1) calcine

Be 50% ~ 55%, TiO by TFe content range ₂content range is 10% ~ 15%, SiO ₂content is 3% ~ 6%, Al ₂o ₃content is 3% ~ 6%, the ratio of the v-ti magnetite concentrate of S content >0.5% 1:0.1 ~ 0.2 by weight adds CaO, at the temperature of 800 DEG C ~ 1400 DEG C, carry out calcining 20 ~ 60 minutes, forms calcination product A;

2) alkali oxide leaching

Calcination product A in step 1) is placed in the alkaline solution that mass concentration is 5% ~ 52%, adds oxygenant, then at the temperature of 220 DEG C ~ 330 DEG C, alkali soaks reaction 0.5 ~ 2 hour, and obtain filtrate and alkali leaching cake B, described filtrate feeds recovery and processing system;

3) classification

By step 2) in alkali leaching cake B add water, form the ore pulp of mass concentration 20% ~ 25% and feed swirler and carry out classification, classification goes out sand setting C and overflow D, described sand setting C to be TFe content range be 62% ~ 69% final iron ore concentrate, described overflow D simmer down to TiO ₂content range is the ilmenite concentrate of 36% ~ 52%.

2. according to claim 1ly utilize calcining, alkali oxide leaching and classification to select the method for v-ti magnetite concentrate again, it is characterized in that: described alkaline solution is any one in the NaOH aqueous solution, the KOH aqueous solution or NaOH and KOH mixed aqueous solution.

3. the method utilizing calcining, alkali oxide leaching and classification to select v-ti magnetite concentrate more according to claim 1, is characterized in that: described oxygenant is O ₂or H ₂o ₂, described O ₂add-on is 20 ~ 120psi, H ₂o ₂add-on is 50 ~ 200kg/t _{to ore deposit}.