JPS6311526A - Production of iron oxide for raw material of ferrite - Google Patents

Abstract

PURPOSE:To efficiently produce iron oxide for the raw material of ferrite which is little in impurities and is graded in fine particles by making hematite-base ore to aq. slurry and removing gangue mineral content with a cyclone and magnetic separation and thereafter crushing and classifying it. CONSTITUTION:Foreign materials incorporated in hematite ore of a raw material are removed by a screen 3, and water is simultaneously fed and the mixture is regulated to the prescribed slurry concn. in a tank 4. Then it is introduced under pressure into a cyclone 5 to concentrate the impurities and is sent to a concentration tank 7 to remove about 40% of impurities. After feeding an underflow 8 to a wet crusher 10 and crushing it into 9-16mum average particle diameter, it is fed to a wet magnetic separator 11 to separate gangue mineral. Then it is dehydrated by a dehydrator 12 and dried by a dryer 13. Successively it is fed to a dry secondary crusher 16 via a dry primary crusher 14 and a distribution tank 15 for dry powder and furthermore passed through a pneumatic classifier 17. Thereby the following iron oxide for the raw material of ferrite is obtained which is graded so that the average particle diameter is not more than 4mum and the proportion not more than 20mum is not less than 99.9% and is little in impurities content.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for producing high purity iron oxide with extremely low impurities and excellent ferrite raw material using hematite iron ore as a raw material. .

[Conventional technology]

High-quality iron ore has traditionally been used after pulverization as an extender for low-grade magnetic materials or general magnetic materials, but due to its high impurity content, its use as a raw material for general ferrite is limited. It could not be used in large quantities as a bulking material.

Therefore, at present, iron oxide as a raw material for ferrite is mainly dependent on by-products generated from rolling processes in steel mills.

[Problem that the invention seeks to solve]

As mentioned above, products made from iron ore have many impurities and their uses are restricted, and products made from iron ore byproducts are affected by the operating status of the steelworks, so there are problems such as the timing of supply and demand not necessarily matching. Ta.

In view of the current situation, the present inventors have conducted extensive research into a method for producing fine iron oxide, which uses abundant iron ore as a raw material, has extremely low impurities, and has a uniform particle size and can be used as a raw material for general ferrite. It is a completed invention.

[Means for solving problems]

That is, the gist of the present invention is that hematite ore is first made into a water slurry with an ore weight ratio of 10 tsun or less and fed to a wet cyclone, the gangue components isolated in the ore are removed, and then the gangue components are After the stone content has been removed, the underflow content is pulverized to an average particle size of 9 to 16 μm, wet magnetic separation is carried out, the remaining gangue content is thoroughly removed, and the resulting ore is repeatedly crushed and classified to obtain an average particle size. This is a method for producing iron oxide for use as a ferrite raw material, characterized in that the iron oxide is sized to have a diameter of 4 μm or less, a ratio k 99.9'Z of 20 or less, or more.

The hematite ore used in the present invention includes:
For example, 5t02, k120x, , MnO, S
, C.L.

It is preferable to use an ore with a small gangue component in which the sum of impurities such as MgO and CaO is 5 or less. In the first reserve treatment process, it is important to enter and exit the liquid cyclone as a water slurry with a thin concentration of less than 10% by weight.
The outside of the clay is removed.

The ore treated in this manner is wet-pulverized to a particle size suitable for wet magnetic separation in the next step. Through this crushing, the gangue content included in the ore as above 5i02, Aj%
205, MnO, CaO, etc. are separated. The t-ore crushed to the optimum particle size is processed using a high magnetic force type wet magnetic separator, for example.
Alternatively, it is separated into gangue containing Fe2O3, which is a pervasive substance, and non-magnetic substances, such as 5i02, A#203, etc., using a high-gradient wet magnetic separator.

After the ore purified in this manner and with impurities removed is completely dehydrated and dried, it is efficiently sized using a combination of a crusher and a classifier to a ratio of average particle diameters of 4 μm or less and 20 μm or less to 999 μm or more.

Specific embodiments will be described below by way of example.

〔Example〕

FIG. 1 is a flow diagram showing an embodiment of the present invention.

After the raw material hematite ore is put into the raw material receiving tank 1, it is cut out quantitatively by the pump ξ-2, and then passed through the foreign matter removal screen 3.
Remove foreign objects and simultaneously supply all the water, and keep the tank 4 at a specified level (1
0 壬 or less) is adjusted to sura'J - dark W. The properties of the raw material ore are shown in Table-1.

Table 1: Properties of raw material iron ore The slurry, which has been adjusted to a predetermined concentration, is forced into a plurality of cyclones 5 by a pump. A slurry in which impurities such as clay are concentrated is sent to the oats flow part 6, and then sent to the concentration tank 7 by a pump. Approximately 40% of impurities in the ore are removed here. On the other hand, the underflow 8 from the cyclone 5 with reduced impurities is sent by a pump 9 to a wet pulverizer 10 for the next wet pulverization process. Notes on oat mer flow and underflow at this time are as shown in Table 2 and Table 3.

The ore is pulled in a wet crusher 10 to have an average particle size of 9 to 16
Wet magnetic separator 1 for the next wet magnetic separation process after wet pulverization into micrometers
Sent to 1. Figure 2 shows the average grain size and magnetic separation results. As is clear from this.

When the average particle size is finer than 9 μm, it is 5i02 or AA2.
05's content increases. This is because heteroaggregation occurs with atomization, and the separation of gangue and ore deteriorates. Moreover, if the particle size is larger than 16 μm, the separation of the ore and the gangue becomes insufficient, and the particle size of 5 in2. A#203 etc. remain in the ore and cannot be separated.

Therefore, it is important to adjust the particle size of the crushed material within the above particle size range in order to maximize rapid efficiency.

The particle size distribution after wet pulverization, the properties of the magnetically separated precipitate, and the notes of the magnetically separated non-magnetized material are shown in Tables 41, 51, and 6, respectively.

1-Co---1 After finishing the wet magnetic separation and before moving on to the drying process, the dehydrator 12
and then dried in a dryer 13 to a moisture content of 0.5 or less. The dried product is crushed in a dry back crusher 14, then sent to a dry secondary crusher 16 via a dry powder distribution tank 15, further adjusted to a predetermined particle size distribution by an air classifier 17, and then sent to a product tank 18. enter.

The obtained product is weighed, packed in bags, etc., and shipped.

In addition, the particle size distribution after dry secondary grinding, the particle size distribution after dry secondary grinding, the particle size distribution of the coarsely classified powder, and the particle size distribution of product C (classified fine powder) are shown in Table 79, Table 8, Table 91, respectively. It is as shown in 10. Table 11 shows the properties of the obtained product.

〔Effect of the invention〕

According to the method of the present invention, abundant hematite iron ore is used as a raw material, and iron oxide for ferrite raw material, which has very few impurities and whose particle size has been adjusted to fine particles, can be used in many ways as a ferrite raw material. You can get a good deal. In addition, according to the present invention, conventional ferrite raw materials have been determined to be mostly dependent on by-products generated in the rolling process of steel mills, so the production is affected by the operating status of steel mills, and there is also the disadvantage that the timing of supply and demand does not always match. However, such problems are solved, and the industrial significance of the present invention is extremely large.

[Brief explanation of drawings]

FIG. 1 is a flowchart showing an example of the present invention, and FIG. 2 is a graph showing the relationship between average particle size and magnetic separation results. DESCRIPTION OF SYMBOLS 1... Raw material ore, 4... Slurry IJ-15... Wet cyclone, 6... Wet type @ machine, 14...-Return crusher, 16... Secondary crusher, 17... ...Wind classifier.

Claims (1)

[Claims] Hematite ore is first made into a water slurry with an ore weight ratio of 10% or less and fed to a wet cyclone to remove the gangue that has been separated into the ore, and then to remove the gangue from which the gangue has been removed. The flow fraction is crushed to an average particle size of 9 to 16 μm, wet magnetic separation is performed to sufficiently remove the remaining gangue, and the thus obtained ore is repeatedly crushed and classified to have an average particle size of 4 μm or less and 20 μm. A method for producing iron oxide for ferrite raw material, characterized by sizing the following ratios to 99.9% or more.