CN111304408A

CN111304408A - Method for refining ferrophosphorus

Info

Publication number: CN111304408A
Application number: CN202010217276.0A
Authority: CN
Inventors: 王勇; 齐涛; 常朝
Original assignee: Institute of Process Engineering of CAS
Current assignee: Institute of Process Engineering of CAS
Priority date: 2020-03-25
Filing date: 2020-03-25
Publication date: 2020-06-19

Abstract

The invention relates to a method for refining ferrophosphorus, which can effectively remove impurity elements of titanium and manganese in the ferrophosphorus and ensure the stability of phosphorus content. The process flow is as follows: 1) preparing the massive ferrophosphorus and the additive into powder; 2) the ferrophosphorus powder and the additive are fully mixed according to a certain proportion and are pressed into blocks; 3) melting the agglomerated sample in a smelting furnace, and simultaneously blowing oxygen for refining to obtain the high-purity refined ferrophosphorus. The method has the advantages of short flow, short reaction time, simple operation, easy industrialization and the like for ferrophosphorus refining and titanium and manganese removal.

Description

Method for refining ferrophosphorus

Technical Field

The invention relates to the technical field of metallurgy, in particular to a method for refining ferrophosphorus, which is used for preparing high-purity amorphous alloy. In particular, a powdery additive is mixed with ferrophosphorus to prepare blocks, so that the melting reaction is accelerated, the energy consumption is reduced, the titanium and manganese are removed through oxygen blowing refining, and the phosphorus loss is reduced.

Background

As a novel energy-saving environment-friendly soft magnetic material, compared with crystalline soft magnetic materials such as traditional electrical steel and the like, the iron-based amorphous alloy has the characteristics of high magnetic permeability, high magnetic induction intensity and high resistivity, and is an indispensable important material for power, electronics, machinery and military industries. Compared with the transformer with electrical steel sheets as iron cores, the no-load loss of the transformer is reduced by about 75%, and the no-load current is reduced by about 80%. In 2018, the consumption of common electrical steel in China exceeds 1000 million tons, the iron-based amorphous alloy is used for replacing the electrical steel, and the iron-based amorphous alloy plays an important role in saving energy of a power grid system in China.

The iron-based amorphous alloy has strict proportion and content among elements, and the control on impurities is strict. The difference between the iron-based amorphous alloy and the foreign high-end product in China is mainly reflected in the aspect of controlling the content of impurities. The ferrophosphorus is a main raw material for manufacturing the iron-based amorphous alloy, but the impurity content in the ferrophosphorus crude product is high and the components are unstable, so that the manufacturing of the iron-based amorphous alloy in China is severely restricted.

The impurity elements in the coarse ferrophosphorus mainly comprise Ti and Mn, and the service performance of the material is influenced by overhigh content of titanium and manganese. The high-purity ferrophosphorus requires that the mass content of Ti is not more than 0.07 percent, the mass content of manganese is not more than 1.00 percent, and the mass content of phosphorus is not less than 23 percent. At present, in the field of alloy refining, the process for removing titanium and manganese from ferrophosphorus is less researched. Therefore, how to perform the titanium and manganese removal on the alloy and improve the kinetic conditions of the titanium and manganese removal are of great significance for alloy refining.

Disclosure of Invention

The invention aims to provide a method for refining ferrophosphorus for the first time according to the characteristics of ferrophosphorus, which is a new method suitable for titanium and manganese removal of ferrophosphorus, and has the advantages of short process flow, simple operation, short reaction time, easy industrialization and wide application prospect.

In order to achieve the purpose, the invention adopts the following scheme:

the technical scheme of the invention is to provide a method for refining ferrophosphorus, which comprises the following steps:

1) mixing ferrophosphorus and an additive according to a mass ratio of 100: (15-20) fully mixing and pressing into blocks;

2) melting the blocked sample, and blowing oxygen for refining; removing the upper layer slag to obtain the high-purity fine ferrophosphorus.

In a preferable scheme, in the massive ferrophosphorus in the step 1), the mass fraction of phosphorus is 20-30%, the mass fraction of titanium is 1.2-1.9%, and the mass fraction of manganese is 2.3-3.0%.

The method of the invention can be suitable for removing titanium and manganese in ferrophosphorus.

In a preferable scheme, the step 1) further comprises the step of grinding the blocky ferrophosphorus into powder (ferrophosphorus with the phosphorus content of 20 wt% -30 wt% is soft) to obtain ferrophosphorus powder, wherein the particle size range of the ferrophosphorus powder is 60-120 mu m.

In a preferred embodiment, the additive in step 1) comprises one or more of hydroxyapatite, chlorapatite and oxygen silicon apatite.

In a preferred scheme, the additive in the step 1) needs to be ground into powder to obtain additive powder.

In a preferable scheme, the particle size range of the additive powder is 60-80 μm.

In a preferred scheme, a sample obtained by mixing the ferrophosphorus and the additive in the step 1) is prepared into blocks by cold pressing, wherein the pressure condition is as follows: 200-270 Mpa, and the pressure time is 20-60 s.

In a preferable scheme, the melting temperature in the step 2) is 1350-1550 ℃.

In a preferred scheme, the oxygen blowing refining time in the step 2) is 15-30 min.

Other operating conditions of the melting and oxygen blowing refining technique of the present invention may be carried out by means of techniques conventional in the art.

Compared with the prior art, the invention has the advantages that:

1. the mixing of the ferrophosphorus powder and the additive increases the reaction contact area, improves the reaction kinetics, reduces the refining time, reduces the cost and simultaneously reduces the melting point of the additive.

2. The additive can inhibit the volatilization of phosphorus during smelting and ensure the stability of phosphorus content.

3. The oxygen blowing refining effectively removes titanium and manganese, the use of the additive promotes the titanium removal and manganese removal reaction and inhibits the titanium return.

4. Short process flow, simple operation, short reaction time and easy industrialization.

Detailed Description

The present invention will be further described with reference to the following specific examples.

Example 1

(1) The content of each element in the original massive ferrophosphorus sample is as follows: ti: 1.25 wt%; mn: 2.94 wt%; p: 26.33 wt%.

Grinding the massive ferrophosphorus, and taking 10g of a sample with the particle size of about 75-100 mu m between 150 meshes and 200 meshes; grinding hydroxyapatite, sieving with 200 mesh sieve to obtain 1.5g sample with particle diameter not greater than 75 μm, and mixing. The mixed sample is pressed for 30s under 200MPa by a tablet press. And (3) taking a proper amount of pressed sample in a crucible, blowing oxygen for smelting for 15min at 1550 ℃, and removing the slag on the upper layer after smelting is finished, wherein the lower layer is refined ferro-phosphorus alloy.

Taking an end-point refined ferrophosphorus sample, and measuring the contents of titanium, manganese and phosphorus, wherein the contents are respectively Ti: 0.04 wt%; mn: 0.85 wt%; p: 24.01 wt%.

Example 2

The content of each element in the original massive ferrophosphorus sample is as follows: ti: 1.70 wt%; mn: 2.85 wt%; p: 27.08 wt%.

Grinding the blocky ferrophosphorus, and taking 10g of a sample with a 200-mesh sieve, wherein the particle size is about 75 mu m; the apatite oxide is ground, 2.0g of sample with a particle size of about 75 μm is taken after 200-mesh sieve, and the mixture is uniformly mixed. The mixed sample is pressed for 30s under 270MPa by a tablet press. And (3) taking a proper amount of pressed sample in a crucible, blowing oxygen for smelting for 15min at 1550 ℃, and removing the slag on the upper layer after smelting is finished, wherein the lower layer is refined ferro-phosphorus alloy.

Taking an end-point refined ferrophosphorus sample, and measuring the contents of titanium, manganese and phosphorus, wherein the contents are respectively Ti: 0.03 wt%; mn: 0.71 wt%; p: 23.82 wt%.

Example 3

The content of each element in the original massive ferrophosphorus sample is as follows: ti: 1.61 wt%; mn: 2.48 wt%; p: 27.46 wt%.

Grinding the blocky ferrophosphorus, and taking 10g of a sample with a 200-mesh sieve, wherein the particle size is about 75 mu m; the apatite oxide is ground, 1.5g of sample with a 200-mesh sieve is taken, the particle size is about 75 mu m, and the materials are uniformly mixed. The mixed sample is pressed for 30s under the condition of 250MPa by a tablet press. And (3) taking a proper amount of pressed sample in a crucible, blowing oxygen for smelting for 15min at 1550 ℃, and removing the slag on the upper layer after smelting is finished, wherein the lower layer is refined ferro-phosphorus alloy.

Taking an end-point refined ferrophosphorus sample, and measuring the contents of titanium, manganese and phosphorus, wherein the contents are respectively Ti: 0.04 wt%; mn: 0.86 wt%; p: 24.33 wt%.

Finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention and are not limited. Although the present invention has been described in detail with reference to the embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. A method of refining ferrophosphorus comprising the steps of:

1) mixing ferrophosphorus and an additive according to a mass ratio of 100: (15-20) uniformly mixing and pressing into blocks;

2) and melting and oxygen blowing refining the agglomerated sample, and removing the upper layer slag to obtain the refined ferrophosphorus.

2. The method of claim 1, wherein: in the ferrophosphorus of the step 1), the mass fraction of phosphorus is 20-30%, the mass fraction of titanium is 1.2-1.9%, and the mass fraction of manganese is 2.3-3.0%.

3. The method of claim 1, further comprising: the step 1) also comprises the step of grinding ferrophosphorus into powder to obtain ferrophosphorus powder; wherein the particle size range of the ferrophosphorus powder is 60-120 mu m.

4. The method of claim 1, wherein: the additive comprises one or more of hydroxyapatite, chlorapatite and oxygen silicon apatite.

5. The method of claim 1, wherein: grinding the additive in the step 1) into powder to obtain additive powder.

6. The method of claim 5, wherein: the particle size range of the additive powder is 60-80 mu m.

7. The method of claim 1, wherein: step 1), mixing ferrophosphorus and an additive, and preparing the mixture into blocks by cold pressing, wherein the pressure conditions are as follows: 200-270 Mpa, and the pressure time is 20-60 s.

8. The method of claim 1, wherein: and 2) melting at 1350-1550 ℃.

9. The method of claim 1, wherein: and 2) oxygen blowing refining for 15-30 min.