阅读说明：本技术 一种含钛海砂矿的烧结冶炼方法 (Sintering smelting method of titanium-containing sea placer ) 是由 俞飞 顾凤义 牛树林 韩萍 闫文凯 于 2021-11-29 设计创作，主要内容包括：本发明涉及海砂矿烧结技术领域,特别是涉及一种含钛海砂矿的烧结冶炼方法。该方法包括如下步骤：向烧结矿中配加含钛海砂矿、含锰菲律宾矿、硼镁铁精粉和其他含铁矿粉；其他某种含铁矿粉的配料量为：X=X′(Y-X1-X2-X3)/Y；LF精炼废渣作为烧结熔剂加入；烧结矿二元碱度R-(2)=CaO/SiO-(2)的控制范围为1.9-2.0；高炉冶炼过程中控制高炉铁水中的Si+Ti的含量在0.3-0.5wt%；高炉炉渣的二元碱度R-(2)控制在1.10-1.15；渣铁出炉后可以经撇渣器的作用渣铁分离,铁水送炼钢车间吹炼,高炉渣经冲渣沟水淬后变为矿渣微粉的原料。解决了配加含钛海砂矿生产的烧结矿转鼓强度低,粒级差的问题。(The invention relates to the technical field of sea sand ore sintering, in particular to a sintering smelting method of titanium-containing sea sand ore. The method comprises the following steps: adding titanium-containing sea placer, manganese-containing Philippine ore, fine boron-magnesium-iron powder and other iron-containing ore powder into the sinter; the other iron-containing mineral powder comprises the following components in parts by weight: x = X' (Y-X1-X2-X3)/Y; adding LF refined waste residues as sintering flux; binary basicity R of sinter 2 =CaO/SiO 2 The control range of (A) is 1.9-2.0; controlling the content of Si and Ti in blast furnace molten iron to be 0.3-0.5wt% in the blast furnace smelting process; binary basicity R of blast furnace slag 2 Controlling the temperature to be 1.10-1.15; after the iron slag is discharged from the furnace, the iron slag can be separated through the action of a slag skimmer, the molten iron is sent to a steelmaking workshop for blowing, and the blast furnace slag is changed into the raw material of slag micro powder after water quenching through a slag sluiceway. Solves the problem of sintering in the production of sea sand ore containing titaniumLow drum strength of ore and poor grain size.)

1. The sintering smelting method of the titanium-containing sea placer is characterized by comprising the following steps:

s1, adding the following iron-containing raw materials into the sintered ore: titanium-containing placer, manganese-containing Philippine mine, fine boron-magnesium-iron powder and other iron-containing mineral powder;

under the condition of ensuring that the total ingredient amount of the iron-containing raw materials is not changed, the addition amount of other iron-containing ore powder is reduced compared with the case of not adding titanium-containing placer, manganese-containing philippine mine and boron-magnesium iron fine powder, but the mass ratio of various other iron-containing ore powder is kept unchanged; the formula for calculating the burden of other iron-containing mineral powder is as follows: x = X' (Y-X1-X2-X3)/Y;

wherein X' is the amount of other iron-containing ore powder when the sintered ore is not added with titanium-containing placer, manganese-containing philippine mine and boron-magnesium-iron fine powder, unit: kg/t ore;

y is total ingredient amount of the iron-containing raw material, unit: kg/t ore;

x1 is the batching of titanium-containing sea placer, unit: kg/t ore;

x2 is the dosage of boron-magnesium-iron fine powder, unit: kg/t ore;

x3 is the ingredient amount of the manganese-containing philippine ore, unit: kg/t ore;

s2, LF refining slag is added as a part of sintering flux, the adding amount is 10kg/t ore, and other fluxes are added according to binary alkalinity R₂And adjusting the addition amount of MgO within the control range;

s3 binary basicity R of sinter₂=CaO/SiO₂The control range of (A) is 1.9-2.0;

s4, blast furnace smelting: controlling the content of Si and Ti in blast furnace molten iron to be 0.3-0.5wt% in the blast furnace smelting process; binary basicity R of blast furnace slag₂Controlling the temperature to be 1.10-1.15; after the iron slag is discharged from the furnace, the iron slag can be separated through the action of a slag skimmer, the molten iron is sent to a steelmaking workshop for blowing, and the blast furnace slag is changed into the raw material of slag micro powder after water quenching through a slag sluiceway.

2. The sinter smelting process for sea sand ore containing titanium as claimed in claim 1, wherein: x1= 50-80; x2= 30; x3= 30.

3. The sinter smelting process for sea sand ore containing titanium as claimed in claim 1, wherein: part of the components of the sea placer are as follows: TFe: 55-58wt% of SiO₂：4-5wt%，Al₂O₃：4-5wt%，TiO₂：9-13wt%。

4. The sinter smelting process for sea sand ore containing titanium as claimed in claim 1, wherein: the content of magnesium oxide in the sintered ore is controlled within the range of 2.0-2.5 wt%.

5. The sinter smelting process for sea sand ore containing titanium as claimed in claim 1, wherein: other iron-containing powders include mixed powders, PB powders, domestic fines and other iron-containing miscellaneous materials.

Technical Field

The invention relates to the technical field of sea sand ore sintering, in particular to a sintering smelting method of titanium-containing sea sand ore.

Background

The sea sand ore original name iron ore sand is a product formed by scouring thick slurry sprayed by volcanoes by seawater. Sea sand ore imported in China at present is mainly produced in Indonesia and New Zealand. Because of the influence of the rising price of the iron ore, domestic steel enterprises gradually turn the eye to non-mainstream ore resources such as titanium-containing sea placer with relatively low price, but the titanium-containing sea placer contains a large amount of TiO₂The method has great influence on the sintering and blast furnace smelting production processes, and sometimes even causes the occurrence of malignant furnace conditions. The addition of titanium-containing sea sand ore mainly causes the reduction of the drum strength of sinter and the deterioration of the grain size. The reason for the quality reduction of the produced sinter is found by research as follows: with TiO₂The content is increased, the perovskite content in the binding phase is obviously improved, the calcium ferrite is in a reduction trend, and the content of the glass phase is increased. The reduction of calcium ferrite is mainly due to TiO₂The increase in CaO, which is required for the formation of calcium ferrite, which is a major source of drum strength of the sinter, causes the sinter to become brittle and the fraction to be poor.

The sintered ore added with the titanium-containing sea placer can generate the conditions of thick slag, poor fluidity, difficult slag-iron separation, poor air permeability of the blast furnace, easy generation of furnace wall thickness and the like during blast furnace smelting. TiO in slag₂When the amount of Ti reduced into Ti entering molten iron is significantly increased, the hearth is reduced, the activity of the hearth is deteriorated, and the furnace condition is deteriorated in a serious case.

Patent CN103924069A discloses a method for preparing oxidative pellets by using iron-containing Indonesia sea sand concentrate as a raw material, which aims to solve the technical problems of providing a method for preparing oxidative pellets which can economically and efficiently perform titanium-containing sea sand concentrate ore dressing to produce high-quality oxidative pellets, but the method does not relate to the influence and solution of adding titanium-containing sea sand ore on sinter, and how to solve the problem of harm caused by high titanium load in the blast furnace ironmaking production in the blast furnace smelting process of the oxidative pellets produced by the method provided by the patent.

Disclosure of Invention

The invention provides a sintering smelting method of titanium-containing sea sand ore aiming at the defects, solves the problems of low drum strength and poor grain size of the sintered ore produced by adding the titanium-containing sea sand ore, and simultaneously solves a series of problems caused by sticky slag iron when the sintered ore produced by smelting the titanium-containing sea sand ore in a blast furnace. The ore blending cost of production is reduced, and the quality of sintered ore and the stable smooth operation of the blast furnace are ensured. And Ti in molten iron is blown and carried to LF refining from converter slag, the LF refining foaming slag enters into the molten steel after being reduced, nitrogen fixation is carried out on the molten steel, ductility of steel is improved, and in addition, the welding performance of the steel can be obviously improved due to the fact that the steel contains a trace amount of titanium. In order to improve the fluidity of blast furnace slag to ensure the stable and smooth operation of the blast furnace, manganese-containing Philippine ore with the manganese content of about 3.5wt% is added in the iron-containing raw material of the sinter to improve the manganese content in the slag and the molten iron, so that the residual manganese after blowing in steel is improved while the smooth operation of the blast furnace is ensured, the dosage of manganese-containing alloy in the steelmaking process is saved, and the production cost is saved.

In order to achieve the purpose, the technical scheme of the invention is as follows:

a sintering smelting method of titanium-containing sea placer comprises the following steps:

s1, adding the following iron-containing raw materials into the sintered ore: titanium-containing placer, manganese-containing Philippine mine, fine boron-magnesium-iron powder and other iron-containing mineral powder;

under the condition of ensuring that the total ingredient amount of the iron-containing raw materials is not changed, the addition amount of other iron-containing ore powder is reduced compared with the case of not adding titanium-containing placer, manganese-containing philippine mine and boron-magnesium iron fine powder, but the mass ratio of various other iron-containing ore powder is kept unchanged; the formula for calculating the burden of other iron-containing mineral powder is as follows: x = X' (Y-X1-X2-X3)/Y;

wherein X' is the amount of other iron-containing ore powder when the sintered ore is not added with titanium-containing placer, manganese-containing philippine mine and boron-magnesium-iron fine powder, unit: kg/t ore;

y is total ingredient amount of the iron-containing raw material, unit: kg/t ore;

x1 is the batching of titanium-containing sea placer, unit: kg/t ore;

x2 is the dosage of boron-magnesium-iron fine powder, unit: kg/t ore;

x3 is the ingredient amount of the manganese-containing philippine ore, unit: kg/t ore;

s2, LF refining slag is added as a part of sintering flux, the adding amount is 10kg/t ore, and other fluxes are added according to binary alkalinity R₂And adjusting the addition amount of MgO within the control range;

s3 binary basicity R of sinter₂=CaO/SiO₂The control range of (A) is 1.9-2.0;

s4, blast furnace smelting: controlling the content of Si and Ti in blast furnace molten iron to be 0.3-0.5wt% in the blast furnace smelting process; binary basicity R of blast furnace slag₂Controlling the temperature to be 1.10-1.15; after the iron slag is discharged from the furnace, the iron slag can be separated through the action of a slag skimmer, the molten iron is sent to a steelmaking workshop for blowing, and the blast furnace slag is changed into the raw material of slag micro powder after water quenching through a slag sluiceway.

Further, X1= 50-80; x2= 30; x3= 30.

Further, the sea placer comprises the following components in part: TFe: 55-58wt% of SiO₂：4-5wt%，Al₂O₃：4-5wt%，TiO₂：9-13wt%；

Further, the content of magnesium oxide in the sintered ore is controlled within a range of 2.0 to 2.5 wt%.

Further, other iron-containing powders include mixed powders, PB powders, domestic fine powders and other iron-containing miscellaneous materials.

The invention has the beneficial effects that:

1. the invention solves the problems of low drum strength and poor grain size of the sinter produced by adding the titanium-containing sea sand ore, and simultaneously solves a series of problems caused by the sticky slag iron when the sinter produced by smelting the titanium-containing sea sand ore in a blast furnace, reduces the ore blending cost of production, and simultaneously ensures the quality of the sinter and the stable and smooth operation of the blast furnace; the Ti in the molten iron is blown and carried to LF refining from converter slag, and enters the molten steel after being refined and reduced to form foamed slag in the LF furnace, so that nitrogen fixation is performed on the molten steel, and the ductility of steel is improved; in addition, the steel contains a trace amount of titanium, so that the welding performance of the steel can be obviously improved; in order to improve the fluidity of the blast furnace slag to ensure the stable and smooth operation of the blast furnace, the manganese-containing Philippine ore with the Mn content of about 3.5wt% is added into the sintering ore to improve the manganese content in the slag and the molten iron, so that the residual manganese after blowing in steel is improved while the smooth operation of the blast furnace is ensured, the addition of manganese-containing alloy in the steelmaking process is saved, and the production cost is saved.

2. Aiming at the conditions that the drum of the sinter is reduced, the content of calcium ferrite is reduced and the glass phase is increased after the titanium-containing sea placer is added, the solution is to improve the alkalinity of the sinter, namely supplement the alkalinity due to TiO₂The increase of calcium titanate causes the increase of calcium titanate, and the formation of the calcium oxide CaO required by the deprived calcium ferrite, and aiming at the grain size deterioration caused by the increase of glass phase, a small amount of boron-magnesium-iron fine powder and B in the boron-magnesium-iron fine powder are added₂O₃Content of about 11wt%, B₂O₃The existence of the glass phase in the sintered ore can effectively reduce the generation amount of the glass phase of the high-temperature liquid phase of the sintered ore in the cooling process, thereby ensuring the size fraction composition of the sintered ore, namely reducing the sintered return ore amount.

3. Aiming at the problem that a series of phenomena which are not beneficial to blast furnace production are caused by slag thickening of a sintering ore in the blast furnace iron making process after titanium-containing sea placer is added, the solution of the problem is to improve the content of manganese oxide MnO in the sintering ore, and manganese-containing Philippine ores with the manganese content of about 3.5wt% are added into the sintering ore to increase the MnO in the blast furnace slag. After blast furnace smelting, part of manganese oxide MnO enters slag, and part of manganese oxide MnO enters molten iron after being reduced, the melting point and the viscosity of blast furnace slag can be reduced by the manganese oxide MnO entering the slag, the fluidity of the molten iron can be effectively improved by Mn entering the molten iron, in addition, in order to ensure that the performance of the blast furnace slag is improved, a trace amount of LF furnace refining waste slag is added into sintering ores, and calcium fluoride CaF in the LF refining waste slag is utilized₂The low melting point property further lowers the melting point of the blast furnace slag and improves the fluidity of the blast furnace slag.

Drawings

FIG. 1 is a process flow diagram of a sintering smelting method of titanium-containing sea sand ore in the invention.

Detailed Description

In order to make those skilled in the art better understand the technical solutions in the present invention, 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 a part of the 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.

The invention discloses a sintering smelting method of titanium-containing sea sand ore, which comprises the following steps:

s1, adding the following iron-containing raw materials into the sintered ore: titanium-containing placer, manganese-containing Philippine ore with Mn content of about 3.5wt%, B₂O₃The boron-magnesium-iron fine powder with the content of about 11wt% and other conventionally used iron-containing mineral powder, wherein the other iron-containing mineral powder comprises mixed powder, PB powder, domestic fine powder and other iron-containing sundries;

(1) wherein the raw materials in each ton of sinter comprise the following components in parts by weight: 50-80kg of titanium-containing placer, 30kg/t of manganese-containing philippine mine and 30kg/t of boron-magnesium-iron fine powder; part of the components of the sea placer are as follows: TFe: 55-58wt% of SiO₂：4-5wt%，Al₂O₃：4-5wt%，TiO₂: 9-13 wt%; adding B-Mg-Fe fine powder into the sinter as B carried by B₂O₃The method has the function of preventing the formation of the glass mineral phase of the sinter, so that the phenomenon of partial crushing of the sinter particle size can be avoided, and the drum strength of the sinter is ensured; the blending of the manganese-containing Philippine ores in the sintered ores aims to improve the fluidity of slag and molten iron by using manganese oxide in limonite;

(2) because titanium-containing placer, manganese-containing Philippine mine and boron-magnesium-iron fine powder are added, under the condition that the total ingredient amount of the iron-containing raw materials is not changed, the amount of other iron-containing ore powder is reduced in proportion, but the mass proportion among various other iron-containing ore powder is kept unchanged; such as: the raw material amount of the titanium-containing sea sand ore is X1, the raw material amount of the boron-magnesium-iron fine powder is 30kg/t ore, the raw material amount of the manganese-containing philippine ore is 30kg/t ore, the other iron-containing powder types are assumed to be 4 ore powders of a, b, c and d, and the raw material amounts of the various ore powders are Xa, Xb, Xc and Xd (unit: kg/t ore); the total charge amount before the iron-containing raw material Y = Xa + Xb + Xc + Xd (kg/t ore), after titanium-containing placer, manganese-containing Philippine mine and boron-magnesium iron fine powder are added, the charge amounts of the original 4 ores are respectively adjusted as follows: xa (Y-X1-30-30)/Y, Xb (Y-X1-30-30)/Y, Xc (Y-X1-30-30)/Y, Xd (Y-X1-30-30)/Y;

(3) the control range of the content of the magnesium oxide in the sintering ore is 2.0-2.5wt%, and is reduced by 0.5wt% compared with the control range without titanium-containing sea sand, so that the rotary drum strength is improved, the sintering size fraction is improved, and the sintering ore contains the manganese oxide brought by manganese-containing Philippines and the calcium fluoride CaF brought by LF refining waste residue₂The fluidity of the slag in the blast furnace is improved, magnesium oxide is not needed to adjust the slag performance, and when the MgO content is higher than 2.5wt%, the strength and the grain size of the sinter are affected;

s2, LF refining slag is added as a part of sintering flux, the adding amount is 10kg/t ore, and other fluxes are added according to binary alkalinity R₂And MgO control range adjusting addition amount;

s3 binary basicity R of sinter₂=CaO/SiO₂The control range of the calcium ferrite is 1.9-2.0, and the alkalinity control range is improved by 0.1 compared with 1.8-1.9 when the titanium-containing sea sand ore is not added, so that sufficient calcium oxide CaO is provided for the formation of the calcium ferrite;

s4, blast furnace smelting: in the blast furnace smelting process, the content of Si and Ti in the blast furnace molten iron is controlled to be 0.3-0.5wt%, because when the content of Si and Ti in the molten iron is more than 0.5wt%, the amount of titanium dioxide reduced into the molten iron is increased, and the fluidity of the molten iron is deteriorated; when the Si + Ti content in the molten iron is less than 0.3wt%, the furnace temperature of the blast furnace is lower, and the furnace condition of the blast furnace tends to be cool; the content of Si and Ti in the molten iron is between 0.3 and 0.5 weight percent, and the fluidity of the molten iron, the fluidity of slag and the furnace temperature are all in good states, so that the method is an ideal operating interval for smooth operation of a blast furnace;

in order to obtain good fluidity of the blast furnace slag, the binary basicity R of the blast furnace slag₂Controlling the temperature to be 1.10-1.15; good slag iron fluidity can quickly infiltrate into a hearth in a soft melting zone in the blast furnace, and the slag iron can be taken out of the furnace to be used as a skimmerThe slag and iron are separated quickly, the molten iron is sent to a steel-making workshop for blowing, and the blast furnace slag is changed into the raw material of slag micro powder after water quenching in a slag flushing channel.

The above process is described in detail below by means of a number of examples and comparative examples:

TABLE 1 sinter partial raw material compounding tables for examples 1 to 4 and comparative examples

TABLE 2 partial indices of titaniferous placer and sinter of examples 1-4 and comparative examples

TABLE 3 blast furnace production part indices of examples 1-4 and comparative examples

Example 1:

according to the table 1, 50kg/t ore of titanium-containing placer is added into the sinter, and the ingredients are as follows: TFe: 55wt% of SiO₂：5.0wt%，Al₂O₃：4.0wt%，TiO₂: 13.0 wt%; adding 30kg/t ore of boron-magnesium-iron fine powder, 30kg/t ore of Philippine ore and other iron-containing raw materials after being reduced in proportion according to the data in the table 1, so that the total iron-containing material dosage is 920kg/t ore, and adding 10kg/t LF refining waste residue of ore; the return mine is a circulating material and is not calculated in the amount of the mixture;

the sintered ore produced according to the proportion has 75.2 percent of drum strength, 155kg/t of return ore, 2.5 percent of MgO content and binary alkalinity R₂Is 1.90; compared with a comparative example, the drum strength of the sinter is slightly improved by 0.2%, the ore return amount is reduced by 5kg/t, the grain size condition is better reflected, the content of magnesium oxide is reduced by 0.2wt%, and the binary alkalinity of the sinter is improved by 0.05;

after the sintered ore produced according to the scheme is smelted by a blast furnace, the Si content of molten iron is 0.34wt percent, and the Ti content isThe amount was 0.16wt%, the amount of Si + Ti was 0.50wt%, and the Mn content was 0.49 wt%. Blast furnace slag binary basicity R in comparison with comparative examples₂Is 1.15, the reduction is 0.03; the blast furnace utilization coefficient is 4.13 tons/(cubic meter day), the blast furnace utilization coefficient is slightly increased by 0.01 ton/(cubic meter day), the MnO content in blast furnace slag is 0.43wt%, the MnO content is increased by 0.1wt%, and TiO is increased by 0.1wt%₂The content is 2.50wt%, and the increase is 1.87 wt%.

After the sintered ore added with titanium-containing sea sand ore is smelted by a blast furnace, the discharged slag iron is separated by a skimmer, and molten iron is transported to steelmaking blowing, and the blast furnace slag is quenched by water and used as the raw material of slag micro powder.

Example 2:

the sintering ore is added with 60kg/t ore of titanium-containing placer, and the components are as follows: TFe: 56% by weight of SiO₂：4.7wt%，Al₂O₃：4.4wt%，TiO₂: 11.6 wt%; adding 30kg/t ore of boron-magnesium-iron fine powder, 30kg/t ore of Philippine ore, and adding other iron-containing raw materials according to the data in Table 1 after the iron-containing raw materials are reduced in proportion, wherein the total iron-containing material dosage is 920kg/t ore, and in addition, adding 10kg/t LF refining waste residue of ore; the return ores are recycled materials and are not calculated in the material proportioning.

The sintered ore produced according to the proportion has 75.1 percent of drum strength, 157kg/t of return ore, 2.2 percent of MgO content and binary alkalinity R₂Is 1.93. Compared with a comparative example, the drum strength of the sinter is slightly improved by 0.1%, the ore return amount is reduced by 3kg/t, the grain size condition is better reflected, the content of magnesium oxide is reduced by 0.5wt%, and the alkalinity of the sinter is improved by 0.08.

After the sintered ore produced according to the scheme is smelted by a blast furnace, the molten iron contains 0.13wt% of Si, 0.17wt% of Ti, 0.30wt% of Si and Ti and 0.42wt% of Mn. Blast furnace slag binary basicity R in comparison with comparative examples₂1.13, a reduction of 0.05; the blast furnace utilization coefficient is 4.12 tons/(cubic meter day), which is equivalent to the comparison example, the MnO content in the blast furnace slag is 0.46wt%, and the MnO content is increased by 0.13wt% compared with the comparison example; TiO 2₂The content is 2.60wt%, and the content is increased by 1.97wt% compared with the comparative example.

After the sintered ore added with titanium-containing sea sand ore is smelted by a blast furnace, the discharged slag iron is separated by a skimmer, and molten iron is transported to steelmaking blowing, and the blast furnace slag is quenched by water and used as the raw material of slag micro powder.

Example 3:

the sintering ore is added with 70kg/t ore of titanium-containing placer, and the components are as follows: TFe: 57% by weight of SiO₂：4.3wt%，Al₂O₃：4.8wt%，TiO₂: 10.4 wt%. Adding 30kg/t ore of boron-magnesium-iron fine powder, 30kg/t ore of Philippine ore, and adding other iron-containing raw materials according to the data in Table 1 after the iron-containing raw materials are reduced in proportion, wherein the total iron-containing material dosage is 920kg/t ore, and in addition, adding 10kg/t LF refining waste residue of ore; the return ores are recycled materials and are not calculated in the material proportioning.

The sintered ore produced according to the proportion has 75.0 percent of drum strength, 159kg/t of return ore, 2.3 percent of MgO content and binary alkalinity R₂It was 1.97. Compared with a comparative example, the drum strength of the sintered ore is kept equal, the ore return amount is reduced by 1kg/t, the reflected grain size condition is slightly better than that of the comparative example, the content of magnesium oxide is reduced by 0.4wt%, and the alkalinity of the sintered ore is improved by 0.12.

After the sintered ore produced according to the scheme is smelted by a blast furnace, the molten iron contains 0.25wt% of Si, 0.19wt% of Ti, 0.44wt% of Si and Ti and 0.46wt% of Mn. Blast furnace slag binary basicity R in comparison with the comparative example₂1.12, a reduction of 0.06; the blast furnace utilization coefficient is 4.13 tons/(cubic meter day), the MnO content in blast furnace slag is slightly increased by 0.44wt% and 0.11wt%, and TiO in the blast furnace slag is slightly increased by 0.01 ton/(cubic meter day)₂The content is 2.58wt% and is increased by 1.95 wt%.

After the sintered ore added with titanium-containing sea sand ore is smelted by a blast furnace, the discharged slag iron is separated by a skimmer, and molten iron is transported to steelmaking blowing, and the blast furnace slag is quenched by water and used as the raw material of slag micro powder.

Example 4:

80kg/t ore of titanium-containing placer is added into the sinter, and the ingredients are as follows: TFe: 58% by weight of SiO₂：4.0wt%，Al₂O₃：5.0wt%，TiO₂: 9.0 wt%. Adding 30kg/t ore of boron-magnesium-iron fine powder, 30kg/t ore of Philippine ore, and adding other iron-containing raw materials according to the data in Table 1 after the iron-containing raw materials are reduced in proportion, wherein the total iron-containing material dosage is 920kg/t ore, and in addition, adding 10kg/t LF refining waste residue of ore; the return ores are recycled materials and are not calculated in the material proportioning.

The drum strength of the sintered ore produced according to the proportion is 75.0 percent, and the return ore amount is 160kg/t oreMgO content 2.0wt%, binary basicity R₂It was 2.00. Compared with the comparative example, the drum strength of the sintered ore is kept equal, the return volume is kept equal, the reflected grain size condition is kept equal to the comparative example, the content of magnesium oxide is reduced by 0.7wt%, and the alkalinity of the sintered ore is improved by 0.15.

After the sintered ore produced according to the scheme is smelted by a blast furnace, the molten iron contains 0.21wt% of Si, 0.22wt% of Ti, 0.43wt% of Si and Ti and 0.45wt% of Mn. Blast furnace slag binary basicity R in comparison with the comparative example₂1.10, a reduction of 0.08; the blast furnace utilization coefficient is 4.12 tons/(cubic meter day), which is equivalent to that of a comparative example; the MnO content in the blast furnace slag is increased by 0.45wt%, increased by 0.12wt%, and TiO₂The content is 2.45wt% and is increased by 1.82 wt%.

After the sintered ore added with titanium-containing sea sand ore is smelted by a blast furnace, the discharged slag iron is separated by a skimmer, and molten iron is transported to steelmaking blowing, and the blast furnace slag is quenched by water and used as the raw material of slag micro powder.

Comparative example:

the iron material addition of the sinter comprises the following steps: 320kg/t ore of mixed powder, 370kg/t ore of PB powder, 160kg/t ore of domestic fine powder and 70kg/t ore of iron-containing miscellaneous materials, and the total amount of iron-containing raw materials is 920kg/t ore. Does not contain titanium-containing placer, fine powder of boron, magnesium and iron, Philippine mine, and does not contain refining waste residue of 10kg/t mine. The return ores are recycled materials and are not calculated in the material proportioning.

The sintered ore produced according to the proportion has 75.0 percent of drum strength, 160kg/t of return ore, 2.7 percent of MgO content and binary alkalinity R₂Is 1.85.

After the sintered ore produced according to the scheme is smelted by a blast furnace, the molten iron contains 0.40wt% of Si, 0.06wt% of Ti, 0.46wt% of Si and Ti, 0.31wt% of Mn and the blast furnace slag has binary alkalinity R₂1.18, blast furnace utilization coefficient 4.12 ton/(cubic meter. day), MnO content in blast furnace slag 0.33wt%, TiO₂The content is 0.63 wt%.

After the sintered ore is smelted by a blast furnace, the discharged slag iron is separated by a skimmer, the molten iron is conveyed to steelmaking blowing, and the blast furnace slag is quenched by water and then used as a raw material of slag micro powder.

As can be seen from the comparison of the 4 examples and the comparative example described above, when the sintered ore is charged with 50 to 80kg/t ore containingTiO in blast furnace slag in titanium sea placer₂Obviously increased, and simultaneously the MnO content in the slag is increased, and the utilization coefficient of the blast furnace is not lower than that of the blast furnace when no sea placer is added in the sinter from the viewpoint of the utilization coefficient of the blast furnace, which shows that the TiO is prepared by the method₂The problem of poor fluidity caused by the increase of the content of the manganese in the blast furnace slag and the molten iron can be solved by the Philippine ore containing the manganese and the LF waste slag. The smooth operation of the blast furnace is not affected by the addition of the titanium-containing sea sand.

In addition, the drum strength of the sinter with the added titanium-containing placer is not lower than that of the sinter without the added titanium-containing placer, which shows that the method increases the alkalinity R of the sinter₂Increasing the CaO content in the sinter, thereby overcoming the defect of TiO₂The content is increased, and the generated perovskite and the generated calcium ferrite rob CaO, so that the problem that the drum strength of the sintering ore is influenced by the reduction of the calcium ferrite in the ore phase is caused. The sintered ore return amount is not higher than that of the comparative example, which shows that the sintered ore grain level is not deteriorated, and the method successfully solves the problem of TiO by adding the boron-magnesium-iron fine powder₂The problem of the increase of glass phase in the mineral phase is brought to sintering.

Although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that various changes in the embodiments and/or modifications of the invention can be made, and equivalents and modifications of some features of the invention can be made without departing from the spirit and scope of the invention.