CN109022788A - A method of preparing ferro-titanium - Google Patents

Abstract

The present invention relates to a kind of method for preparing ferro-titanium, this method carries out gas-based reduction after pelletizing is made in ilmenite first, then using the ilmenite of gas-based reduction as raw material, produces ferro-titanium using self- propagating mode.The method of the present invention this method can not only reduce the quantity of slag caused by the usage amount of reducing agent metallic aluminium and self-propagating reaction needed for self-propagating reaction, but also improve ferro-titanium titanium grade and reduce oxygen content in alloy.

Description

A kind of method for preparing ferro-titanium alloy

technical field

The invention relates to a method for preparing ferro-titanium alloy, which specifically uses gas-based reduced ilmenite as a raw material to prepare ferro-titanium alloy through a self-propagating process, and belongs to the technical field of metallurgy.

Background technique

As an important metal material, ferro-titanium-iron alloy has important applications in industry. In terms of steel, titanium-iron alloys can be used as deoxidizers, degassers and alloying agents to reduce segregation of steel ingots and improve the strength and wear resistance of steel. In addition, in chemical industry and energy, it is also an important electrode coating and hydrogen storage material. At present, its main production process is remelting method and thermite method.

As a titanium-containing raw material, ilmenite has the advantages of abundant reserves and low price, and is often used to produce high-titanium slag and titanium dioxide. However, in the separation process of ferro-titanium, the preparation of high-titanium slag by electric arc furnace consumes a lot of energy, and the production of titanium dioxide by sulfuric acid method produces a large amount of waste liquid. The direct production of ferro-titanium alloy from ilmenite avoids the problem of ferro-titanium separation, reduces the process steps and reduces the production cost. But the disadvantage is that the production of ferro-titanium alloy by the thermite reaction will consume a large amount of metal aluminum and produce a large amount of waste residue. At the same time, due to factors such as Al ₂ O ₃ inclusions in the alloy and incomplete reduction of TiO ₂ , the oxygen content of the ferro-titanium alloy is relatively high, reaching 5-10%, does not meet the export product requirements.

Contents of the invention

(1) Technical problems to be solved

In order to solve the above-mentioned problems in the prior art, the present invention provides a method for preparing ferro-titanium alloy.

(2) Technical solution

In order to achieve the above object, the main technical solutions adopted in the present invention include:

A method for preparing ferro-titanium alloy, comprising the steps of:

S1. After making ilmenite into oxidized pellets, place them in a reducing atmosphere at 800-1300°C for reduction to obtain gas-based reduced ilmenite, grind and pulverize them, and set aside:

S2, mixing the gas-based reduced ilmenite metal aluminum, sodium chlorate, titanium dioxide, calcium oxide and calcium fluoride obtained in step S1 evenly;

S3, using the upper part to ignite, after the reaction is complete, cool, separate the slag, and obtain the ferro-titanium alloy.

In the above-mentioned method, preferably, in step S1, the making of pellets includes the following steps: adding bentonite with a mass fraction of 1-3% to ilmenite, mixing for 2-4 hours, and then gradually adding water Carry out material mixing, then stuffing for 30-40 minutes, pelletize to obtain 5-8mm pellets; after drying the pellets, put them into a muffle furnace for pre-oxidation.

In the above method, preferably, the amount of added water is 5-7% of the weight of ilmenite, and the time for adding water for mixing is 30-60 minutes.

In the above method, preferably, the pre-oxidation temperature in the muffle furnace is 800-1200° C., and the pre-oxidation time is 1-3 hours.

As described above, preferably, in step S1, the reducing atmosphere is at least one of CO, H ₂ , CH ₄ , or at least one of CO, H ₂ , CH ₄ and an inert gas mixed gas.

That is to say, the reducing atmosphere can be any one of CO, H ₂ , CH ₄ , or a mixed gas of any two or three in any proportion, or can be any one of CO, H ₂ , CH ₄ or Mixture of any two with inert gas, the inert gas is N ₂ , Ar, etc.

According to the above-mentioned preparation method, preferably, in step S1, the time for the reduction is 1-5 hours, and the mixture is ground and crushed and passed through a 200-mesh sieve.

In the above-mentioned method, preferably, in step S2, the ratio of the gas-based reduced ilmenite to metal aluminum, sodium chlorate, titanium dioxide, calcium oxide and calcium fluoride is 100:127-146 in mass ratio :37～78:164～190:18～36:6～22 for batching.

In the method described above, preferably, in step S2, the metal aluminum accounts for more than 90% under a 100-mesh sieve, and the sodium chlorate and titanium dioxide account for more than 95% under a 200-mesh sieve.

In the above method, preferably, in step S2, the titanium dioxide can be replaced by rutile or high titanium slag, and the sodium chlorate can be replaced by potassium chlorate.

(3) Beneficial effects

The beneficial effects of the present invention are:

The invention provides a method for producing ferro-titanium alloy by using gas-based reduced ilmenite as raw material and adopting a self-propagating method. The method can not only reduce the usage amount of reducing agent metal aluminum required by the self-propagating reaction and the amount of slag produced by the self-propagating reaction, but also can improve the titanium grade of the ferro-titanium alloy and reduce the oxygen content in the alloy.

Description of drawings

FIG. 1 is a phase diagram of gas-based reduced ilmenite prepared in Example 1.

Detailed ways

In the present invention, the pellets are firstly prepared, then subjected to reduction treatment, and then mixed with metal aluminum, sodium chlorate, titanium dioxide, calcium oxide and calcium fluoride, and then smelted to obtain the ferro-titanium alloy. The main reaction is: 3Fe+NaClO ₃ +6Al+3TiO ₂ =3Al ₂ O ₃ +3FeTi+NaCl, 6Fe+NaClO ₃ +6Al+3TiO ₂ =3Al ₂ O ₃ +3Fe ₂ Ti+NaCl, 4Al+3TiO ₂ = 3Ti+2Al ₂ O ₃ , wherein metal aluminum is used as a reducing agent, sodium chlorate is used as a heating agent, and titanium dioxide is used to improve the titanium grade of ferro-titanium alloy. Calcium oxide and calcium fluoride are used to promote the reduction rate of titanium and improve the fluidity of slag respectively.

In order to better explain the present invention and facilitate understanding, the present invention will be described in detail below through specific embodiments in conjunction with the accompanying drawings.

Example 1

A method for preparing ferro-titanium alloy, comprising the steps of:

1. Preparation of ilmenite by air-based reduction:

Add bentonite with a mass fraction of 2% to ilmenite, mix for 3 hours, then gradually add water accounting for 5% of the weight of raw ilmenite, mix for 4 hours, then stuff for 30 minutes, and pelletize to obtain 5-8mm pellets . After drying the pellets, put them into a muffle furnace at 1000°C for pre-oxidation with air for 2 hours. Afterwards, it was placed in a CO reducing atmosphere at 800°C and 30% N ₂ for 2 h. Obtain reduced ilmenite, grind it until it passes through a 200-mesh sieve, and set aside. The phase diagram of the reduced ilmenite mineral, as shown in Figure 1, shows that the ilmenite oxide pellets can be reduced under this reducing condition, and a large amount of metallic iron is produced.

2. Preparation of ferro-titanium alloy raw materials:

Air-based reduced ilmenite, metal aluminum, sodium chlorate, titanium dioxide, calcium oxide and calcium fluoride are batched according to the mass ratio of 100:134.4:51.7:174.5:26.9:13.5, of which metal aluminum accounts for 90% under a 100-mesh sieve. More than %, sodium chlorate and titanium dioxide account for more than 95% under 200 mesh sieves.

3. Preparation of ferro-titanium alloy:

Mix the raw materials evenly, use the upper part to ignite, and after the reaction is complete, cool and separate the slag to obtain a ferro-titanium alloy, in which the titanium content is 48.2%, the iron content is 25.6%, the aluminum content is 8.47%, and the oxygen content is 1.97%.

Example 2

This embodiment is based on Example 1, the difference is that 1% of bentonite is added, mixed for 4 hours, added water is 6% of ilmenite weight, mixed for 3 hours, stuffed for 35 minutes, to obtain 5-8mm pellets, baked After drying, the ilmenite pellets were pre-oxidized at 800°C for 2 hours in a muffle furnace and reduced in an atmosphere of 1100°C and 100% CO for 5 hours to obtain reduced ilmenite.

Air-based reduced ilmenite, metal aluminum, potassium chlorate, titanium dioxide, calcium oxide and calcium fluoride are mixed according to the mass ratio of 100:138.5:74:189:34.6:11.1, wherein the metal aluminum accounts for more than 90% under a 100-mesh sieve, Potassium chlorate and titanium dioxide account for more than 95% under a 200-mesh sieve.

Mix the raw materials evenly, use the upper part to ignite, and after the reaction is complete, cool and separate the slag to obtain a ferro-titanium alloy, in which the titanium content is 49.6%, the iron content is 26.0%, the aluminum content is 8.12%, and the oxygen content is 3.10%.

Example 3

This example is based on Example 1, the difference is that 3% bentonite is added, 7% water is added, and the material is stuffed for 40 minutes to obtain 5-8mm pellets, which are put into a muffle furnace for pre-oxidation at 1200°C after drying. The 1-hour ilmenite pellets were reduced in an atmosphere of 1200° C. and 100% H for ₃ hours to obtain reduced ilmenite, which was ground until it passed through a 200-mesh sieve and set aside.

Air-based reduced ilmenite, metal aluminum, sodium chlorate, titanium dioxide, calcium oxide and calcium fluoride are mixed according to the mass ratio of 100:136:58:187:20.8:13.9, of which metal aluminum accounts for 90% under a 100-mesh sieve Above, sodium chlorate and titanium dioxide account for more than 95% under 200 sieves.

Mix the raw materials evenly, use the upper part to ignite, and after the reaction is complete, cool and separate the slag to obtain a ferro-titanium alloy, in which the titanium content is 50.8%, the iron content is 25.3%, the aluminum content is 8.23%, and the oxygen content is 3.27%.

Example 4

This example is based on Example 1, the difference is that 2.5% of bentonite is added, 6% of water is added, and the material is stuffed for 35 minutes to obtain 5-8mm pellets. The ilmenite pellets oxidized for 3 hours were reduced in an atmosphere of 1100° C., 70% CH ₄ and 30% Ar for 3 hours to obtain reduced ilmenite, which was ground until it passed through a 200-mesh sieve and set aside.

Air-based reduced ilmenite, metal aluminum, potassium chlorate, titanium dioxide, calcium oxide and calcium fluoride are mixed according to the mass ratio of 100:137:65:184:27.7:11.1, wherein metal aluminum accounts for more than 90% under a 100-mesh sieve, Potassium chlorate and titanium dioxide under 200 sieve accounted for more than 95%.

Mix the raw materials evenly, use the upper part to ignite, and after the reaction is complete, cool and separate the slag to obtain a ferro-titanium alloy, in which the titanium content is 49.3%, the iron content is 26.1%, the aluminum content is 7.83%, and the oxygen content is 4.11%.

It can be known by calculation that using the gas-based reduced ilmenite of the present invention as a raw material to prepare ferro-titanium alloy can save about 16% of metal aluminum and reduce about 14% of ferro-titanium slag. If a certain amount of preheating is carried out on the raw materials for the preparation of the ferro-titanium alloy or a certain amount of reaction heat is provided by electric energy, the effect will be more remarkable.

Comparative example 1

The ilmenite powder was roasted at 600°C for 2 hours to remove moisture and organic matter.

The ilmenite powder, metal aluminum, sodium chlorate, titanium dioxide, calcium oxide and calcium fluoride are batched according to the mass ratio of 100:133:49:171:27:13.

Finally, a ferro-titanium alloy is obtained, wherein the titanium content is 47.7%, the iron content is 25.1%, the aluminum content is 6.83%, and the oxygen content is 6.17%.

Comparative example 2

Roast ilmenite powder at 1000°C for 2 hours to remove moisture and organic matter.

The ilmenite powder, metal aluminum, sodium chlorate, titanium dioxide, calcium oxide and calcium fluoride are batched according to the mass ratio of 100:130:43:65:33:10.

Finally, a ferro-titanium alloy is obtained, wherein the titanium content is 47.0%, the iron content is 23.8%, the aluminum content is 6.92%, and the oxygen content is 6.39%.

It can be seen from the above that after the gas-based reduction pretreatment is adopted in the present invention, the titanium grade of the ferro-titanium alloy can be effectively improved compared with the method without pretreatment in the comparative example, and the oxygen content is greatly reduced, and the amount of waste residue generated is also greatly reduced.

The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention in other forms. Any person skilled in the art can use the technical content disclosed above to change or modify it into an equivalent embodiment with equivalent changes. . However, any simple modifications, equivalent changes and modifications made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention still belong to the protection scope of the technical solution of the present invention.

Claims (9)

1. a kind of method for preparing ferro-titanium, which is characterized in that it includes the following steps:

S1, it after pelletizing is made in ilmenite, puts it into reduction in 800~1300 DEG C of reducing atmosphere and obtains gas-based reduction titanium Iron ore is ground, spare:

S2, gas-based reduction ilmenite and metallic aluminium, sodium chlorate, titanium dioxide, calcium oxide and calcirm-fluoride that step S1 is obtained are mixed It closes uniform；

S3, it is lighted a fire using top, it is cooling after fully reacting, slag is separated, ferro-titanium is obtained.

2. the method as described in claim 1, which is characterized in that in step sl, it is described be made pelletizing include the following steps: to Ilmenite adds the bentonite that its mass fraction is 1~3%, and 2~4h of mixing is gradually added into water later and carries out mixing, then bored Expect 30~40min, pelletizing obtains 5~8mm pelletizing；After pelletizing drying, it is put into blowing air in Muffle furnace and carries out pre- oxygen Change.

3. method according to claim 2, which is characterized in that the amount that water is added is the 5~7% of ilmenite weight, is added Enter water and carries out the time of mixing as 30-60min.

4. method according to claim 2, which is characterized in that Pre oxidation is 800~1200 DEG C in the Muffle furnace, in advance Oxidization time is 1~3h.

5. the method as described in claim 1, which is characterized in that in step sl, the reducing atmosphere is CO, H₂、CH₄In At least one, or be CO, H₂、CH₄At least one of gaseous mixture with inert gas.

6. the method as described in claim 1, which is characterized in that in step sl, the time of the reduction is 1~5h, grinding Smash it through 200 meshes.

7. the method as described in claim 1, which is characterized in that in step s 2, the gas-based reduction ilmenite and metallic aluminium, Sodium chlorate, titanium dioxide, calcium oxide and calcirm-fluoride proportion in mass ratio for 100:127~146:37~78:164~190:18~ 36:6~22 carries out ingredient.

8. the method as described in claim 1, which is characterized in that in step s 2, accounted under 100 mesh of metallic aluminium 90% with On, 95% or more is accounted under 200 mesh of the sodium chlorate and titanium dioxide.

9. the method as described in claim 1, which is characterized in that in step s 2, the titanium dioxide rutile or high titanium Slag replacement, the sodium chlorate are replaced with potassium chlorate.