阅读说明：本技术 一种基于铁矿石高温冶金性能的配矿方法 (Ore blending method based on high-temperature metallurgical performance of iron ore ) 是由 王永红 于原浩 孙立伟 刘广 秦玉栋 于 2019-09-11 设计创作，主要内容包括：本发明揭示了一种基于铁矿粉高温冶金性能的配矿方法,选取多种以上不同产地的铁矿粉,对不同铁矿粉的高温冶金性能进行测试分析,通过数据分析得出高温冶金性能值与化学成分的数学模型,进行铁矿粉高温冶金性能的优劣搭配,得到高温冶金性能优良、适宜烧结的混匀粉。本发明的方法揭示了单一矿及混合矿高温冶金性能值与化学成分之间的关系,以此为基础进行优化配矿,可得到高温冶金性能优良的混合矿,有利于烧结提高产量,改善烧结矿质量；同时在混矿时可利用不同铁矿粉高温冶金性能的互补,提高非主流低价矿的使用比例,降低烧结原料成本。(The invention discloses an ore blending method based on high-temperature metallurgical performance of iron ore powder, which comprises the steps of selecting more than one kinds of iron ore powder with different production places, testing and analyzing the high-temperature metallurgical performance of the different iron ore powder, obtaining a mathematical model of a high-temperature metallurgical performance value and chemical components through data analysis, and carrying out good and bad matching on the high-temperature metallurgical performance of the iron ore powder to obtain mixed powder which is good in high-temperature metallurgical performance and suitable for sintering. The method disclosed by the invention reveals the relationship between the high-temperature metallurgical property values and the chemical components of the single ore and the mixed ore, optimizes ore blending on the basis of the relationship, can obtain the mixed ore with excellent high-temperature metallurgical property, is beneficial to sintering, improves the yield and improves the quality of the sintered ore; meanwhile, the complementation of the high-temperature metallurgical properties of different iron ore powder can be utilized during ore mixing, the use proportion of non-mainstream low-price ore is improved, and the cost of sintering raw materials is reduced.)

1. An ore blending method based on high-temperature metallurgical performance of iron ore powder is characterized by comprising the following steps: comprises the following steps of (a) carrying out,

s1, selecting iron ore powder, namely selecting a group of iron ore powder in different producing areas, and measuring the chemical component content of the different iron ore powder by an XRF (X-ray fluorescence) analysis method;

s2, testing the high-temperature metallurgical performance, namely, firstly, sampling and crushing iron ore powder, screening powder with the particle size of less than 150 meshes, and testing the high-temperature metallurgical performance values of different iron ore powder by using a micro sintering device;

s3, carrying out data analysis on the tested high-temperature metallurgical performance value and the chemical components of the corresponding iron ore powder, and determining a mathematical model;

s4, determining the optimal high-temperature metallurgical performance value of the mixed ore by combining the experimental result, the ore blending data of the production field and the performance index of the sintered ore;

s5, selecting a proper mineral powder combination according to the high-temperature metallurgical performance value of the mineral powder to match the high-temperature metallurgical performance, optimizing ore blending and sintering.

2. The method of claim 1, wherein: in step S1, the different producing areas include brazil, australia, india, philippines, iran, selareon, south africa, and ukraine.

3. The method of claim 1, wherein: in the step S1, the chemical component is SiO₂、Al₂O₃、CaO。

4. The method of claim 1, wherein: in the step S2, the pyrometallurgical property values include an assimilation temperature LAT, a liquid fluidity FI, and a binder phase strength BST.

5. The method of claim 1, wherein: in step S3, the mathematical model is:

assimilation temperature LAT 1320.67-156.25 (Al)₂O₃/SiO₂)

Liquid phase fluidity index FI { (CaO)_{Outer cover}-2×SiO₂)/TFe}/Al₂O₃

Strength of binder phase BST, definition B ═ Al₂O₃/(SiO₂-2CaO_{Inner part})

When B is present<0.4,BST＝-278.22-9022.27×B²+4353.03×B

When B is greater than 0.4, BST-442.87 +1111.83 XB

Wherein: CaO (CaO)_{Outer cover}CaO and CaO supplemented in mineral powder for maintaining certain alkalinity in laboratory_{Inner part}The various constituents present in the model represent the weight percentage of the ore fines, which are the CaO contained in the ore fines themselves.

6. The method of claim 5, wherein: the determination of the mathematical model may include,

performing multiple linear regression calculation according to chemical components, assimilation temperature values, liquid phase fluidity values and binding phase strength values of the iron ore powder in different production places,

when the linear regression of the strength and the components of the binding phase is carried out, firstly, the B value is calculated, a curve is made according to the B value and the BST, an inflection point is found, and the determined B value is a threshold value.

7. The method of claim 1, wherein: in the step S4, the optimal pyrometallurgical performance value is: the assimilation temperature LAT is 1230-1260 ℃, the liquid phase fluidity FI is 1.4-1.8, and the binding phase strength BST is 400-800N.

8. The method of claim 7, wherein: in the step S4, the optimal pyrometallurgical performance value of the mixed ore is determined by combining the experimental result, the ore blending data in the production field and the performance index of the sintered ore, which specifically comprises the following steps,

and collecting ore blending lists of a production site in a standard time period, calculating the high-temperature metallurgical performance value of each ore blending list according to the model, counting corresponding sinter quality index values, and counting and analyzing the corresponding high-temperature metallurgical performance value range when the sintering quality index is relatively excellent.

9. The method of claim 1, wherein: in the step S5, a proper combination of ore powders is selected according to the pyrometallurgical performance of the ore powders for good and bad matching of pyrometallurgical performance, which specifically includes the following steps,

and when the optimized ore blending is carried out, setting the range of chemical components and the range of metallurgical performance values of the mixed powder, carrying out the optimized ore blending calculation, and further calculating the proportion of ores of different producing areas.

Technical Field

The invention relates to the technical field of iron and steel smelting, in particular to an ore blending method based on the high-temperature metallurgical performance of iron ore.

Background

The blending of the sintered and uniformly mixed ore is to mix different ore powders according to the requirements of the sintering process so that the chemical components of the uniformly mixed ore meet the index requirements of the sintering and blending process. With the reduction and exhaustion of high-quality iron ore resources, the varieties of iron ores used by current enterprises are more and more, the stability of component granularity and the like is also poor, and no enterprises using single ore for sintering production exist, so that the ores of different varieties need to be optimally matched, and the mixed ore with stable component granularity and excellent metallurgical performance is mixed for sintering production. However, how to match the components of iron ores of different varieties into uniform ore with proper performance and cost meeting the enterprise requirements becomes a critical affair.

At present, the chemical components of the blending ore are mainly considered in the blending of the sintering blending ore, and other physical chemistry, high-temperature metallurgical performance and sintering performance of the ore powder are rarely considered. The basic method is to mix ores by experience, the randomness is larger, or the cost is lost, the purpose of reducing the cost is achieved, but the sintering performance is poor or worsened, or the sintering performance is optimized but the cost is greatly increased, so that the cost is not paid.

After the research of a comparison system is carried out on the comprehensive furnace burden of a blast furnace in part of domestic iron and steel plants, the reasonable furnace burden structure is determined by resource conditions, the technical level of ore processing, equipment conditions, the price and metallurgical performance of agglomerated finished ore; therefore, finding a reasonable comprehensive charge material structure is a complicated system engineering, and finding the optimal matching proportion suitable for the blast furnace of an operator in the reasonable comprehensive charge material structure is a technical problem which is very difficult to solve. Because a blast furnace comprehensive burden ore blending mode based on adding acid burden (acid pellet ore, natural lump ore and the like) to high-alkalinity sinter ore can obtain better pig iron smelting effect and obtain better blast furnace production technical and economic indexes, people form a fixed ore blending ratio mode in long-term blast furnace production, for example, the proportion of the blast furnace entering the sinter ore is generally over 75 percent, the quality and the cost of the sinter ore have important influence on the smelting of the blast furnace, and the quality and the cost of the sinter ore are mainly influenced by the cost and the quality of the blended ore.

Disclosure of Invention

The invention aims to overcome the defect that the existing mixed ore only starts from components, and provides an ore blending method based on the high-temperature metallurgical performance of iron ore.

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

an ore blending method based on the high-temperature metallurgical performance of iron ore powder comprises the following steps,

s1, selecting iron ore powder, namely selecting a group of iron ore powder in different producing areas, and measuring the chemical component content of the different iron ore powder by an XRF (X-ray fluorescence) analysis method;

s2, testing the high-temperature metallurgical performance, namely, firstly, sampling and crushing iron ore powder, screening powder with the particle size of less than 150 meshes, and testing the high-temperature metallurgical performance values of different iron ore powder by using a micro sintering device;

s3, carrying out data analysis on the tested high-temperature metallurgical performance value and the chemical components of the corresponding iron ore powder, and determining a mathematical model;

s4, determining the optimal high-temperature metallurgical performance value of the mixed ore by combining the experimental result, the ore blending data of the production field and the performance index of the sintered ore;

s5, selecting a proper mineral powder combination according to the high-temperature metallurgical performance value of the mineral powder to match the high-temperature metallurgical performance, optimizing ore blending and sintering.

Preferably, the different origins include brazil, australia, india, philippines, iran, selareon, south africa, ukraine.

Preferably, in step S1, the chemical component is SiO₂、Al₂O₃、CaO。

Preferably, in step S2, the pyrometallurgical performance values include an assimilation temperature LAT, a liquid fluidity FI, and a binder phase strength BST.

Preferably, in step S3, the mathematical model is:

assimilation temperature LAT 1320.67-156.25 (Al)₂O₃/SiO₂)

Liquid phase fluidity index FI { (CaO)_{Outer cover}-2×SiO₂)/TFe}/Al₂O₃

Bonding ofPhase strength BST, definition B ═ Al₂O₃/(SiO₂-2CaO_{Inner part})

When B is present<0.4,BST＝-278.22-9022.27×B²+4353.03×B

When B is greater than 0.4, BST-442.87 +1111.83 XB

Wherein: CaO (CaO)_{Outer cover}CaO and CaO supplemented in mineral powder for maintaining certain alkalinity in laboratory_{Inner part}The various constituents present in the model represent the weight percentage of the ore fines, which are the CaO contained in the ore fines themselves.

Preferably, the determination of the mathematical model comprises,

performing multiple linear regression calculation according to chemical components, assimilation temperature values, liquid phase fluidity values and binding phase strength values of the iron ore powder in different production places,

when the linear regression of the strength and the components of the binding phase is carried out, firstly, the B value is calculated, a curve is made according to the B value and the BST, an inflection point is found, and the determined B value is a threshold value.

Preferably, in the step S4, the optimal pyrometallurgical performance value is: the assimilation temperature LAT is 1230-1260 ℃, the liquid phase fluidity FI is 1.4-1.8, and the binding phase strength BST is 400-800N.

Preferably, in the step S4, the method for determining the optimal pyrometallurgical performance value of the mixed ore by combining the experimental result, the ore blending data in the production field and the performance index of the sintered ore specifically includes the following steps: and collecting ore blending lists of a production site in a standard time period, calculating the high-temperature metallurgical performance value of each ore blending list according to the model, counting corresponding sinter quality index values, and counting and analyzing the corresponding high-temperature metallurgical performance value range when the sintering quality index is relatively excellent.

Preferably, in the step S5, a proper combination of ore powders is selected according to the pyrometallurgical performance values of the ore powders to perform good and bad matching of the pyrometallurgical performance, which specifically includes the following steps: and when the optimized ore blending is carried out, setting the range of chemical components and the range of metallurgical performance values of the mixed powder, carrying out the optimized ore blending calculation, and further calculating the proportion of ores of different producing areas.

The invention has the following beneficial effects: the iron ore powder with different high-temperature metallurgical performance values is subjected to complementary matching of quality and fineness; when the assimilation temperature of the blended ore is 1230-1260 ℃, the liquidity of the liquid phase is 1.4-1.8, and the strength of the bonding phase is 400-800N, the formation of the liquid phase is facilitated, the liquidity of the liquid phase is slowed down, the strength of the formed liquid phase bonding phase after cooling can be ensured, the cold strength of the sintered ore is facilitated to be improved, and the fuel consumption of sintering production is also facilitated to be reduced; when the assimilation temperature is 1230-1260 ℃, the production of calcium ferrite is facilitated, and the reducibility of the sinter is improved; due to the fact that proper assimilation temperature is limited, the non-mainstream ores with low liquid phase generation temperature and high liquid phase generation temperature and relatively low purchase cost can be reasonably matched, and the ore blending raw material cost is greatly reduced.

Detailed Description

The method provided by the invention keeps the high-temperature metallurgical performance value of the uniformly mixed ore within a proper range by reasonably optimizing ore blending according to the high-temperature metallurgical performance of different iron ore powder, is beneficial to reducing the liquid phase generation temperature in the sintering process, improving the strength of a binding phase in the sintering process, improving the generation amount of the composite calcium ferrite of the sintered ore species, improving the reducibility of the sintered ore, improving the cold strength of the sintered ore, reducing the fuel consumption and simultaneously reducing the cost of mixed ore raw materials.

Specifically, the ore blending method based on the high-temperature metallurgical performance of the iron ore comprises the following steps:

s1, selecting 10 or more than 10 iron ore powders in different producing areas, and measuring the chemical component contents of the different iron ore powders by an XRF (X-ray fluorescence) fluorescence analysis method;

s2, testing the high-temperature metallurgical performance, namely firstly crushing the selected iron ore powder of different producing areas, and screening out particles below 150 meshes to be detected; secondly, a micro sintering device is used for testing the high-temperature metallurgical performance value;

s3, determining a mathematical model, namely performing data analysis on the tested high-temperature metallurgical performance value and the chemical components of the corresponding iron ore powder to determine the mathematical model; the mathematical model is as follows:

temperature of assimilationLAT＝1320.67-156.25×(Al₂O₃/SiO₂)

Liquid phase fluidity index FI { (CaO)_{Outer cover}-2×SiO₂)/TFe}/Al₂O₃

Strength of binder phase BST, definition B ═ Al₂O₃/(SiO₂-2CaO_{Inner part})

When B is present<0.4,BST＝-278.22-9022.27×B²+4353.03×B

When B is greater than 0.4, BST-442.87 +1111.83 XB

Wherein: CaO (CaO)_{Outer cover}CaO and CaO supplemented in mineral powder for maintaining certain alkalinity in laboratory_{Inner part}The ore powder contains CaO, and each component appearing in the model represents the weight percentage of the CaO in the iron ore powder;

s4, determining a proper metallurgical property value of the mixed ore, and determining the optimal high-temperature metallurgical property value of the mixed ore by combining the experimental result, the ore blending data of the production site and the performance index of the sintered ore, wherein the method specifically comprises the following steps: collecting ore blending lists of a production site in a standard time period, calculating the high-temperature metallurgical performance value of each ore blending list according to the model, simultaneously counting the corresponding sintered mineral quality index value, and counting and analyzing the corresponding high-temperature metallurgical performance value range when the sintering quality index is better; the optimal pyrometallurgical performance value is as follows: the assimilation temperature LAT is 1230-1260 ℃, the liquid phase fluidity FI is 1.4-1.8, and the binding phase strength BST is 400N-800N;

and S5, calculating the pyrometallurgical performance values of the mixed ores, namely calculating the pyrometallurgical performance values of the mixed ores by combining chemical components of the mixed ores according to the determined mathematical model.

S6, optimizing ore blending, namely selecting 5-6 kinds of suitable ore powder according to the high-temperature metallurgical property value of the ore powder to match the high-temperature metallurgical property, optimizing the ore blending and sintering, and specifically comprising the following steps: and when the optimized ore blending is carried out, setting the range of chemical components and the range of metallurgical performance values of the mixed powder, carrying out the optimized ore blending calculation, and further calculating the proportion of ores of different producing areas.

Generally, the more calcium ferrite is contained in the sintered ore, the better the reducibility of the sintered ore and the higher the strength; calcium ferrite can be generated in large quantity at 1250 ℃, and when the temperature is continuously increased to exceed 1280 ℃, the generated calcium ferrite can be decomposed in large quantity, and the quantity of calcium ferrite in the sintered ore is influenced. The statistics of a large number of experimental and production practice data show that: generally, when the assimilation temperature of the blended ore is 1230-1260 ℃, the liquid phase fluidity index is 1.4-1.8, and the strength of a binding phase is 400N-800N, the generation amount and the crystal form of calcium ferrite are the best, and the sinter ore has better drum strength, grain size composition and reducibility. The proper high-temperature metallurgical property value of the uniformly mixed ore determined by the invention can well meet the requirements of calcium ferrite generation amount and crystal form, and the sintered ore has better metallurgical property and quality after sintering. Therefore, the assimilation temperature in the selected pyrometallurgical performance values is 1230-1260 ℃, the liquidity of the liquid phase is 1.4-1.8, and the strength of the bonding phase is 400N-800N.

The following is a demonstration by a specific experiment.

And selecting 12 iron ore powders of different producing areas to carry out an experiment for optimizing ore blending. The iron ore powder of different producing areas has different chemical components and different internal structures, so the following actual measurement results have different results, and the influence of the chemical components is the most important, and the influence caused by the different structures is not considered in the invention. In this example, the content (weight percentage) of chemical components of different iron ore powders was measured by XRF (fluorescence analysis).

This example was carried out in a micro sintering apparatus and a sintering cup experimental apparatus. Such as that disclosed in chinese patent 201110091029.1 "method for studying sintering properties of iron ore using micro sintering test".

(1) Selection of iron ore powder

Selecting 12 iron ore powders with different production places, wherein the grade is from 55% to 65%.

(2) Iron ore powder metallurgy performance test

And respectively crushing the selected iron ore powder, screening to obtain the particle size below 150 meshes, and testing the high-temperature metallurgical performance by using a micro sintering device. The requirement for the particle size is mainly considered to be the requirement for sample preparation in the experimental process.

(3) Optimizing ore blending

And matching the high temperature metallurgical property values of the iron ore powder, optimizing the ore blending and controlling the high temperature metallurgical property values of the mixed ore within the required range.

(4) Experiment in a sintering cup

According to the optimized ore blending scheme, blending the uniformly mixed ore, then carrying out a sintering experiment on sintering cup equipment, and carrying out test analysis on sintering indexes.

(5) Results of the experiment

TABLE 1 iron ore powder high-temp. metallurgical property test values

TABLE 2 Ore blending protocol

TABLE 3 optimization of post-ore-blending pyrometallurgical performance values

TABLE 4-1 sintering index before and after optimization

TABLE 4-2 sintering indices before and after optimization