阅读说明：本技术 一种钒钛磁铁矿高炉冶炼的方法 (Blast furnace smelting method of vanadium titano-magnetite ) 是由 刘华 周平 刘德安 杨泸 姜子文 闵荣辉 于 2020-12-11 设计创作，主要内容包括：本发明公开一种钒钛磁铁矿高炉冶炼的方法,所述方法包括将炉料进行高炉炼铁,得到铁水和炉渣,所述高炉冶炼的炉料包括：烧结矿、球团矿和长石精矿,所述烧结矿、球团矿和长石精矿的质量比为100:(10-25):(5-10)。所述高炉冶炼过程中的风温为1200-1300℃,富氧率为4-10％。本发明提供的钒钛磁铁矿高炉冶炼方法将常规的铁精矿替换为铁锰矿和铬铁矿,充分利用了攀西地区丰富的铁尾矿,对于尾矿再利用具有重要意义,并且通过实验证明这种替换对高炉冶炼的利用系数和燃料比均无显著影响,具有可行性。(The invention discloses a blast furnace smelting method of vanadium titano-magnetite, which comprises the following steps of carrying out blast furnace ironmaking on furnace burden to obtain molten iron and slag, wherein the furnace burden for blast furnace smelting comprises the following components: the high-temperature-resistant sintered ore comprises sintered ore, pellet ore and feldspar ore concentrate, wherein the mass ratio of the sintered ore to the pellet ore to the feldspar ore concentrate is 100 (10-25) to (5-10). The air temperature in the blast furnace smelting process is 1200-1300 ℃, and the oxygen enrichment rate is 4-10%. The blast furnace smelting method of the vanadium titano-magnetite replaces the conventional iron ore concentrate with the iron-manganese ore and the chromite, fully utilizes rich iron tailings in Panxi area, has important significance for recycling the tailings, and has no obvious influence on the utilization coefficient and the fuel ratio of blast furnace smelting through experiments, thereby having feasibility.)

1. The blast furnace smelting method of the vanadium titano-magnetite is characterized in that furnace burden is subjected to blast furnace ironmaking to obtain molten iron and slag, and the furnace burden for the blast furnace smelting comprises the following steps: the high-temperature-resistant sintered ore comprises sintered ore, pellet ore and feldspar ore concentrate, wherein the mass ratio of the sintered ore to the pellet ore to the feldspar ore concentrate is 100 (10-25) to (5-10).

2. The method as claimed in claim 1, wherein the blast furnace smelting process has a blast temperature of 1200 ℃ and 1300 ℃ and an oxygen enrichment rate of 4-10%.

3. The method according to claim 1, wherein the sintered ore comprises the following raw materials in parts by mass: 50-70 parts of vanadium-titanium magnetite concentrate, 20-30 parts of iron-manganese ore, 10-20 parts of chromite, 5-10 parts of fuel and 10-20 parts of flux.

4. The method of claim 3, wherein the fuel is coke and coal fines and the flux is selected from the group consisting of activated lime and quicklime.

5. The method according to claim 1, wherein the sintered ore is prepared by the following method: mixing the vanadium-titanium magnetite concentrate, the iron-manganese ore, the chromite, the fuel and the flux according to the proportion, and sintering to obtain the sinter.

6. The method according to claim 1, wherein the pellet ore comprises the following raw materials in parts by mass: 80-90 parts of vanadium-titanium magnetite concentrate, 1-8 parts of binder and 5-10 parts of water, wherein the binder is selected from bentonite.

7. The method according to claim 1, wherein the pellet ore is prepared by: mixing the vanadium-titanium magnetite concentrate, a binder and water to obtain a mixture, and pelletizing to obtain pellets; and drying, preheating and roasting the pellets to obtain pellets.

8. The method as claimed in claim 7, wherein the drying temperature is 500-600 ℃, the preheating temperature is 800-1000 ℃, and the baking temperature is 1200-1300 ℃.

9. The method as claimed in claim 7, wherein the average particle size of the pellets is 10-50mm, wherein the ratio of the particle size of 10-20mm should be 80% or more.

10. The method according to any one of claims 1 to 9, wherein the vanadium-titanium magnetite concentrate is produced from Panxi area of China, and comprises the main components of 55-65% TFe and 1-2% SiO in percentage by mass₂、0.5-1％CaO、0.5-2％MgO、1-2％Al₂O₃、0.6-1％V₂O₅、5-9％TiO₂。

Technical Field

The invention belongs to the technical field of steel smelting, and particularly relates to a method for blast furnace smelting of vanadium titano-magnetite.

Background

Vanadium titano-magnetite is a very important iron ore resource and is present in many countries and regions around the world. The Panxi area of China has abundant vanadium titano-magnetite resources, but the produced vanadium titano-magnetite has the characteristics of low ore grade, multi-element symbiosis, low iron and high titanium, complex ore structure and the like. Due to the particularity, the smelting cost of the vanadium-titanium magnetite produced in the Panxi area of China is higher than that of the similar iron ore. However, with the gradual decrease of conventional iron ore resources, the low-cost smelting of vanadium titano-magnetite has a very important meaning and is a hot problem which is continuously researched by the technicians in the field.

At present, the conventional blast furnace vanadium titano-magnetite smelting method comprises the following steps: sintering vanadium-titanium-iron ore concentrate and common fine ore to produce sintered ore, pelletizing the vanadium-titanium-iron ore concentrate and the common iron ore concentrate to produce oxidized pellet ore, adding the sintered ore, the pellet ore and a small amount of lump ore into a blast furnace together with coke according to a certain proportion, blowing the coke at the lower part to generate reducing gas, leading the ore to be reduced by the ascending of the reducing gas and the descending of furnace burden, then melting and dropping the ore into a furnace hearth to finish the iron-making smelting process, and realizing the separation of slag and iron.

In order to solve the common technical problem, patent document 201810915866.3 discloses a blast furnace smelting method of high-grade vanadium titano-magnetite, which comprises mixing sintered ore and pellet ore to perform blast furnace smelting, and obtaining molten iron and slag. The raw materials of the sinter comprise: vanadium-titanium magnetite concentrate, iron concentrate, active lime and fuel; the pellet is prepared by pelletizing vanadium-titanium magnetite concentrate and bentonite.

Patent document 201810916711.1 discloses a blast furnace iron-making method of all-vanadium titano-magnetite, which is to blast furnace iron-make the charging material under the condition of blowing auxiliary fuel to obtain molten iron and slag. The furnace burden comprises 85-95 parts by mass of vanadium-titanium pellets and 5-15 parts by mass of limestone ore; the vanadium-titanium pellet is obtained by roasting a mixture of vanadium-titanium-iron ore concentrate, bentonite and quicklime.

Patent document 201410218986.X discloses a method for smelting vanadium titano-magnetite in a blast furnace, which takes 70-80 parts of sintered ore, 20-25 parts of pellets and 2-5 parts of lump ore as raw materials, and adds coke accounting for 20-30% of the weight of the raw materials for blast furnace smelting. The sintered ore is obtained by sintering 35-50 parts of vanadium-titanium magnetite concentrate, 25-40 parts of common iron ore, 2-5 parts of iron-manganese ore, 4-6 parts of fuel and 14-16 parts of solvent. The pellet is prepared from 95-98 parts of vanadium-titanium magnetite concentrate, 2-5 parts of bentonite and 6-8 parts of added water through pelletizing, drying and roasting.

Patent document 201810952882.X discloses a blast furnace smelting method of vanadium titano-magnetite of high-proportion pellet ore, and the blast furnace smelting furnace charge comprises the following steps: pellet ore, common lump ore and steel slag. The preparation method of the pellet ore comprises the following steps: mixing vanadium-titanium-iron ore concentrate, a binder and a flux to obtain a mixture; mixing the mixture with water, and pelletizing to obtain pellets; and drying, preheating and roasting the pellets to obtain pellets.

Patent document 201811098874.X discloses a blast furnace smelting method of vanadium-titanium magnetite, which realizes blast furnace strengthening smelting of the vanadium-titanium magnetite through high wind temperature and high oxygen enrichment rate of vanadium-titanium sinter ore, vanadium-titanium pellet ore and steel slag, and simultaneously recovers iron and vanadium in the steel slag. The raw materials for preparing the sintered ore preferably comprise: vanadium-titanium magnetite concentrate, ordinary iron concentrate, flux and fuel. The raw materials for preparing the pellet ore preferably comprise: vanadium-titanium magnetite concentrate and a binder.

The invention provides a method for smelting vanadium-titanium magnetite in a blast furnace by combining the characteristics of mineral resources in Panxi area, wherein iron ore concentrate is replaced by iron manganese ore and chromite on the basis of the conventional technology, so that the iron manganese ore and chromite in Panxi iron tailings are effectively utilized, and the method contributes to the reutilization of the tailings.

Disclosure of Invention

The invention aims to provide a blast furnace smelting method of vanadium titano-magnetite, which replaces iron ore concentrate conventionally used for preparing sintered ore with iron manganese ore and chromite, and makes full use of abundant iron tailings in Panxi area although the slag yield is increased due to the increase of the specific gravity of iron ore, thereby having important significance for recycling the tailings. Secondly, a small amount of feldspar ore concentrate is added into the blast furnace smelting furnace material, and the feldspar ore concentrate is an aluminosilicate mineral rich in alkali metals such as potassium, sodium, calcium and the like. The inventor unexpectedly discovers that the efficiency of separating the slag from the molten iron in the blast furnace can be improved and the slagging-off iron loss can be reduced by adding a proper amount of feldspar concentrate into the blast furnace smelting furnace material.

The purpose of the invention is realized by the following technical scheme.

In a first aspect, the invention provides a blast furnace smelting method of vanadium titano-magnetite, which is characterized in that furnace burden is subjected to blast furnace ironmaking to obtain molten iron and slag, wherein the furnace burden for blast furnace smelting comprises the following steps: the high-temperature-resistant sintered ore comprises sintered ore, pellet ore and feldspar ore concentrate, wherein the mass ratio of the sintered ore to the pellet ore to the feldspar ore concentrate is 100 (10-25) to (5-10).

The air temperature in the blast furnace smelting process is 1200-1300 ℃, and the oxygen enrichment rate is 4-10%.

The sintered ore comprises the following preparation raw materials in parts by weight: 50-70 parts of vanadium-titanium magnetite concentrate, 20-30 parts of iron-manganese ore, 10-20 parts of chromite, 5-10 parts of fuel and 10-20 parts of flux.

The sintered ore is prepared by the following method: mixing the vanadium-titanium magnetite concentrate, the iron-manganese ore, the chromite, the fuel and the flux according to the proportion, and sintering to obtain the sinter.

The fuel is coke and coal powder, the coke is used in an amount of 400-450kg/t iron, and the coal powder is used in an amount of 100-150kg/t iron.

The flux is selected from the combination of active lime and quick lime, and the mass ratio of the active lime to the quick lime is 1: 1.

The vanadium-titanium magnetite concentrate used by the invention is produced in Panxi area of China, and the main components of the vanadium-titanium magnetite concentrate comprise 55-65% of TFe and 1-2% of SiO in percentage by mass₂、0.5-1％CaO、0.5-2％MgO、1-2％Al₂O₃、0.6-1％V₂O₅、5-9％TiO₂。

The iron-manganese ore used by the invention is produced in Panxi area of China, and the main components of the iron-manganese ore comprise 30-35% of TFe and 22-29% of SiO in percentage by mass₂、0.1-1％CaO、10-15％MnO、0.1-0.5％V₂O₅。

The chromite used by the invention is produced in Panxi area of China, and the main components of the chromite comprise 30-40% of TFe and 10-25% of Cr by mass percentage₂O₃、10-15％SiO₂、1-2％Al₂O₃、0.1-2％MgO、1-3％CaO。

The pellet ore comprises the following preparation raw materials in parts by weight: 80-90 parts of vanadium-titanium magnetite concentrate, 1-8 parts of binder and 5-10 parts of water.

The preparation method of the pellet ore comprises the following steps: mixing the vanadium-titanium magnetite concentrate, a binder and water to obtain a mixture, and pelletizing to obtain pellets; and drying, preheating and roasting the pellets to obtain pellets. The drying temperature is 500-600 ℃, the preheating temperature is 800-1000 ℃, and the roasting temperature is 1200-1300 ℃.

The average grain diameter of the pellet is 10-50mm, wherein the proportion of the grain diameter of 10-20mm is more than or equal to 80%.

The binder is selected from bentonite.

The feldspar ore concentrate used in the invention is an aluminosilicate mineral rich in alkali metals such as potassium, sodium, calcium and the like, and is produced in Panxi area of China. The inventors of the present invention have unexpectedly found that the addition of feldspar concentrates to blast furnace smelting furnace charge reduces the iron loss during the skimming process. The reason for analysis is that the feldspar ore concentrate can increase the melting point of the surface slag, so that part of molten iron is prevented from being taken away by the slag in the slag skimming process due to the thick and thin state of the slag, the separation effect of the slag and the molten iron is improved, and the iron loss of the skimming is effectively reduced.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below, and it is obvious that the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Blast furnace smelting implementing method for vanadium titano-magnetite

Example 1

Preparing sintered ore: 70 parts of vanadium-titanium magnetite concentrate, 30 parts of iron-manganese ore, 20 parts of chromite, 6 parts of coke powder, 2 parts of coal powder, 10 parts of active lime and 5 parts of quick lime are stirred and mixed, water is added to form a mixture with the water content of 8%, the mixture is added into a belt type sintering machine for gas ignition sintering, and the height of a material layer is controlled at 600-800 mm.

Preparing pellets: mixing 90 parts by weight of vanadium-titanium magnetite concentrate and 5 parts by weight of bentonite after burdening, adding 6 parts by weight of water, pelletizing to prepare pellets, and drying, preheating and roasting the pellets to obtain pellet ore. The drying temperature is 500 ℃, the drying time is 12 minutes, the preheating temperature is 1000 ℃, the preheating time is 20 minutes, the roasting temperature is 1200 ℃, and the roasting time is 40 minutes.

Blast furnace smelting: 100 parts by weight of sintered ore and 25 parts by weight of pellet ore are mixed into a blast furnace, 5 parts by weight of feldspar concentrate are added for smelting, the air temperature is controlled to be 1300 ℃, and the oxygen enrichment rate reaches 4 percent to obtain molten iron and furnace slag. And detecting the alkalinity of the slag, carrying out slag skimming by using a slag skimming machine until slag and iron are separated, and calculating the iron loss of the slag skimming. And calculating the utilization coefficient and the fuel ratio of the vanadium-titanium magnetite in the blast furnace smelting process according to the data of the amount of molten iron produced per cubic meter of the effective volume of the blast furnace every day. The data of the results are shown in Table 1.

Example 2

The preparation of the sintered ore and the pellet ore is the same as that of the example 1, in the blast furnace smelting process, 100 parts by weight of the sintered ore and 25 parts by weight of the pellet ore are mixed into a blast furnace, 8 parts by weight of feldspar concentrate is added for smelting, and the smelting conditions are the same as that of the example 1. And detecting the alkalinity of the slag, carrying out slag skimming by using a slag skimming machine until slag and iron are separated, and calculating the iron loss of the slag skimming. And calculating the utilization coefficient and the fuel ratio of the vanadium-titanium magnetite in the blast furnace smelting process according to the data of the amount of molten iron produced per cubic meter of the effective volume of the blast furnace every day. The data of the results are shown in Table 1.

Example 3

The preparation of the sintered ore and the pellet ore is the same as that of the example 1, in the blast furnace smelting process, 100 parts by weight of the sintered ore and 25 parts by weight of the pellet ore are mixed into a blast furnace, 10 parts by weight of feldspar concentrate is added for smelting, and the smelting conditions are the same as that of the example 1. And detecting the alkalinity of the slag, carrying out slag skimming by using a slag skimming machine until slag and iron are separated, and calculating the iron loss of the slag skimming. And calculating the utilization coefficient and the fuel ratio of the vanadium-titanium magnetite in the blast furnace smelting process according to the data of the amount of molten iron produced per cubic meter of the effective volume of the blast furnace every day. The data of the results are shown in Table 1.

Comparative example 1

The preparation of the sintered ore and the pellet ore is the same as that in example 1, in the blast furnace smelting process, 100 parts by weight of the sintered ore and 25 parts by weight of the pellet ore are mixed into a blast furnace, and the smelting is carried out without lengthening the stone concentrate, and the smelting conditions are the same as that in example 1. And detecting the alkalinity of the slag, carrying out slag skimming by using a slag skimming machine until slag and iron are separated, and calculating the iron loss of the slag skimming. And calculating the utilization coefficient and the fuel ratio of the vanadium-titanium magnetite in the blast furnace smelting process according to the data of the amount of molten iron produced per cubic meter of the effective volume of the blast furnace every day. The data of the results are shown in Table 1.

Comparative example 2

The sintered ore was prepared in the same manner as in example 1 except that 30 parts by weight of the heterolite and 20 parts by weight of the chromite were replaced with 25 parts by weight of the general iron concentrate in which the TFe was 60-70%.

The pellet ore was prepared in the same manner as in example 1, and in the blast furnace smelting process, 100 parts by weight of the sintered ore and 25 parts by weight of the pellet ore were mixed into the blast furnace, and 5 parts by weight of the feldspar concentrate was added to perform smelting under the same conditions as in example 1. And detecting the alkalinity of the slag, carrying out slag skimming by using a slag skimming machine until slag and iron are separated, and calculating the iron loss of the slag skimming. And calculating the utilization coefficient and the fuel ratio of the vanadium-titanium magnetite in the blast furnace smelting process according to the data of the amount of molten iron produced per cubic meter of the effective volume of the blast furnace every day. The data of the results are shown in Table 1.

TABLE 1 blast furnace smelting results of vanadium titano-magnetite

It can be seen from the data of the basicity of the slag after blast furnace smelting, that the basicity of the slag obtained by blast furnace smelting according to the method provided by the invention has an obvious positive correlation with the addition amount of feldspar concentrate, and from the examples 1-3, the basicity of the slag obtained is larger as the addition amount of the feldspar concentrate is larger. This is because feldspar concentrates, the constituents of which are alkali or alkaline earth aluminosilicates, normally result in an increase in slag basicity after addition as a charge. In addition, the addition amount of feldspar ore concentrate is also correlated with the slagging-off iron loss, which is reduced from 3.7% to 3.3% in example 1 compared to comparative example 1 without lengthening the stone ore concentrate, and further reduced to 3.0% (example 2) and 2.9% (example 3) as the addition amount of feldspar ore concentrate increases. Comparative example 2 the feldspar concentrate of example 1 was added in the same amount, but the reason why the slagging-off iron loss was lower than that of example 1 is that comparative example 2 itself produces a smaller amount of slag and the amount of iron removed by the slag during slagging-off is correspondingly reduced.

According to the data of the utilization coefficient and the fuel ratio shown in the table, the data of the examples 1 to 3 and the data of the comparative example 1 have no significant difference and no regular change trend, which shows that the feldspar ore concentrate has no significant correlation with the utilization coefficient and the fuel ratio, and the addition amount of the feldspar ore concentrate does not influence the utilization coefficient and the fuel ratio of blast furnace smelting. Comparing example 1 with comparative example 2, we can see that there is no significant difference in the utilization factor and fuel ratio data between the two, which demonstrates the fact that it is feasible to replace common iron concentrate with ferromanganese and chromite ore according to the present invention, after replacing the ferromanganese and chromite ore according to the present invention with common iron concentrate having comparable iron content. The discovery lays a certain research foundation for the recycling of the iron tailings in the Panxi area.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.