CN1147599C

CN1147599C - Smelt-reduction process for preparing Al-Si-Fe alloy from Al dregs

Info

Publication number: CN1147599C
Application number: CNB011187700A
Authority: CN
Inventors: 金明官; 夫; 丰田哲夫
Original assignee: Tetsuo Refining Industry Co Ltd; Beijing Institute Of Circulation Chemistry
Current assignee: Tetsuo Refining Industry Co Ltd; Beijing Institute Of Circulation Chemistry
Priority date: 2001-06-12
Filing date: 2001-06-12
Publication date: 2004-04-28
Anticipated expiration: 2021-06-12
Also published as: CN1328165A

Abstract

The present invention relates to a fusion-reduction method of producing Al-Si-Fe alloy as a deoxidizing agent of steel making. The method comprises the steps: aluminum slag containing aluminum and aluminum oxide of different contents in different batches is blended into aluminum slag powder with correspondingly stable chemical components; the aluminum slag powder, silica powder, rust and carbon powder are produced into an agglomerate composite moulding object by waste heavy oil as an adhesive agent; the composite moulding object is added to a reacting furnace for a fusion-reduction reaction at 1400 to 1800DEGC for 1 hour to 2 hours, thereby obtaining the Al-Si-Fe alloy. The Al-Si-Fe alloy contains the following chemical components (weight %): 40 to 45 wt% of Al, 35 to 40 wt% of Si, and 15 to 25 wt% of Fe. The Al-Si-Fe alloy has the advantages of stable chemical components, low cost and no environmental pollution.

Description

Smelting reduction method for producing ferro-silicon-aluminum alloy from aluminum slag

Technical Field

The invention relates to a smelting reduction method for producing a steelmaking deoxidizer Al-Si-Fe alloy, belonging to the technical field of steelmaking.

Background

The Al-Si-Fe alloy is a deoxidizer used in the steel-making process and is widely used in many steel mills at home and abroad. At present, the method for producing ferro-silicon-aluminum by using electric furnace method is available at home and abroad, the method uses aluminium slag as raw material to produce ferro-silicon-aluminum, such as CN1088622A, the disadvantage is that the chemical composition of aluminium slag varies with production batch, the chemical composition of the ferro-silicon-aluminum product is unstable, and the use effect is affected, the other fatal disadvantage of the method is that during the forming process of aluminium slag, water-based adhesive-paper pulp waste liquid is used, water in the waste liquid reacts with Al-N in the aluminium slag to form NH₃And the surrounding environment is polluted.

Disclosure of Invention

Therefore, the invention provides a smelting reduction method for producing ferro-silicon-aluminum by using aluminum slag powder, silica powder, rust powder and carbon powder with uniform components. The method comprises the steps of mixing different batches of aluminum slag containing aluminum and aluminum oxide with different contents into aluminum slag powder with relatively stable chemical components, preparing the aluminum slag powder, silica powder, rust and carbon powder into a blocky mixed forming object by using waste heavy oil as an adhesive, putting the blocky mixed forming object into a reaction furnace, and carrying out a melting reduction reaction for 1-2 hours at the temperature of 1400-1800 ℃ to obtain the ferro-silicon-aluminum. The ferro-silicon-aluminum alloy has stable chemical components, low cost and no environmental pollution.

The aim of the invention is realized by the following steps (the following mixture ratio is weight percent):

1. mixing aluminum slag containing aluminum and aluminum oxide in different batches uniformly, repeatedly ball-milling and sieving by using a ball mill until chemical components of 10-15% of Al and Al are screened out₂O₃65-75% of aluminum slag powder, the balance of impurities and the granularity of less than 100 meshes (0.154 mm).

2. 40-50% of aluminum slag powder and SiO₂30-4% of silica and/or silica sand with a content of 95% or more0％，Fe₂O₃10-20% of iron rust (such as iron scale frequently generated in steel mill workshops of steel mills) with the content of more than 90%, and carbon powder with the content of more than 85% of C. The granularity of the silica and/or the silica sand is 3-6 mm, and the granularity of the carbon powder is less than 0.104 mm. The adding amount of the carbon powder is 28-38% of the total weight of the aluminum slag powder, the iron rust, the silica and/or the silica sand.

3. The aluminum slag powder, the rust, the silica and/or the silica sand and the carbon powder mixture are bonded together into a blocky mixed molding by using the waste heavy oil as a bonding agent. The adding amount of the waste heavy oil is 5-15% of the total weight of the aluminum slag powder, the iron rust, the silica and/or the silica sand and the carbon powder. The particle size of the blocky mixed forming object is preferably 2-6 cm blocky.

4. And (2) putting the mixed forming object into a reaction furnace (such as an electric arc furnace or a submerged arc furnace commonly used in chemical plants for producing calcium carbide), and carrying out a melting reduction reaction for 1-2 hours at the temperature of 1400-1800 ℃. After the reaction, the melt is poured into a receiving tank and naturally cooled into bulk sendust. The aluminum-silicon-iron alloy comprises the following chemical components: 40-45% of Al, 35-40% of Si and 15-25% of Fe.

The principle of the smelting reduction method for producing ferro-silicon-aluminum by using aluminum slag powder, silica powder, iron rust powder and carbon powder is as follows:

Al₂O₃、SiO₂、Fe₂O₃reduction, which has the reaction formula:

the block-shaped mixed molding can react in a reaction furnace at 1400-1800 ℃.

Its stoichiometric formula can be written as follows:

when the method of the invention is used for producing the ferro-silicon-aluminum, the obtained chemical components (weight percent) are as follows: al 40-45%, Si 35-40%, Fe 15-25%.

The method of the invention has the following advantages:

①, in the method, the aluminum slag powder with relatively stable chemical components, which is processed by different batches of aluminum slag, is a renewable resource withrelatively stable chemical components.

②, when the method is used for producing Al-Si-Fe, the electricity consumption is reduced by 10-20%, thereby saving energy and reducing the production cost.

The energy-saving reason is as follows: in the method, aluminum slag powder, rust powder, silica powder and carbon powder are mixed according to a proportion and processed into a block-shaped molding material which is put into a reaction furnace. Therefore, the heat transfer effect among the components is good, and the heat consumption is reduced according to the principle that the melting point of the mixture is reduced, thereby achieving the effect of saving electric energy. From experimental data, the power consumption for producing each ton of ferro-silicon-aluminum by using the prior art method is 12000-13000 WHA; by using the method, the power consumption for producing each ton of ferro-silicon-aluminum is only 10000-11000 WHA.

③ in the method of the present invention, the binder used for mixing the aluminum dross powder, the silicon powder and the carbon powder is oily substance-waste heavy oil, thus no NH is generated₃(ii) a The current method uses an aqueous material as a binder to generate NH₃Causing environmental pollution.

④, the iron rust powder used in the method of the invention is the waste of steel mills, in particular the scale-surface oxides which frequently occur in steel mill rolling plants, called black skin, where Fe₂O₃The content is more than 90%. The method uses the iron rust powder as a secondary resource, thereby achieving the recycling of the iron rust powder.

⑤, the rust powder and the waste heavy oil used in the method are all wastes, the price is low, and the product cost can be greatly reduced.

Detailed Description

Example 1

The chemical components (weight percent) are Al 13 percent and Al₂O₃70 percent of aluminum slag powder with the balance of impurities 1500kg and SiO₂1300kg of 96% silica powder, Fe₂O₃In an amount of 90%600kg of rust powder, 1250kg of anthracite powder with 88 percent of C content and 465kg of waste heavy oil as a binding agent are mixed and molded to prepare the anthracite powder with the particle size of 20 multiplied by 20mm³And (5) block-shaped solid matters. And putting the mixed forming product into a 12000KWH electric furnace (a reaction furnace with a self-baking electrode for producing calcium carbide), gradually heating, and carrying out a melting reduction reaction for 1.8 hours at 1400-1700 ℃. After the reaction is finished, the molten product is poured into a separation receiving groove and naturally cooled to 10 multiplied by 8 multiplied by 5cm³And (4) a block. The electric energy consumed for producing one ton of ferro-silicon-aluminum is 11000 WHA. Finally, 998kg of the ferro-silicon-aluminum (in weight percent) with the following components is obtained:

Al 42％，Si 38％，Fe 20％。

example 2

The chemical components (weight percent) are 15 percent of Al and 15 percent of Al₂O₃1800kg of aluminum slag powder with 68 percent of impurities and the balance of SiO₂1440kg of 96% silica powder, Fe₂O₃360kg of 90% rust powder, 1330kg of 90% C anthracite powder and 493kg waste heavy oil as adhesive are mixed and molded to prepare 30X 30mm³And (5) block-shaped solid matters. And putting the mixed forming product into a 12000KWH electric furnace (a reaction furnace with a self-baking electrode for producing calcium carbide), gradually heating, and carrying out a melting reduction reaction for 1.2 hours at 1500-1800 ℃. After the reaction is finished, the molten product is poured into a separation receiving groove and naturally cooled to 10 multiplied by 8 multiplied by 5cm³And (4) a block. The electric energy consumed for producing one ton of sendust is about 10000 WHA. 1150kg of ferro-silicon-aluminum (in weight percent) with the following components are obtained finally: 45% of Al, 39% of Si and 16% of Fe.

Example 3

Chemical components (weight percent) of Al 14 percent and Al₂O₃69 percent of aluminum slag powder with the balance of impurities of 2000kg and SiO₂97% silica flour 1540kg, Fe₂O₃620kg of rust powder with the content of 92 percent, 1540kg of anthracite powder with the content of 90 percent by mixing 570kg of waste heavy oil as a binding agent to form the mixture into a size of 40 multiplied by 40mm³And (5) block-shaped solid matters. Putting the mixed forming object into a 12000KWH electric furnace (a reaction furnace with a self-baking electrode for producing calcium carbide), gradually heating, and melting at 1450-1750 DEG CThe melting reduction reaction was carried out for 1.5 hours. After the reaction is finished, the molten product is poured into a separation receiving groove and naturally cooled to 10 multiplied by 8 multiplied by 5cm³And (4) a block. The electric energy consumed for producing one ton of ferro-silicon-aluminum is 10500 WHA. 1500kg of ferro-silicon-aluminum (in weight percent) with the following components are obtained: 44% of Al, 36% of Si and 20% of Fe.

Claims

1. A melting reduction method for producing steelmaking deoxidizer Al-Si-Fe alloy comprises the following steps:

(1) mixing aluminum slag containing aluminum and aluminum oxide in different batches uniformly, and repeatedly ball-milling and sieving by using a ball mill until the screened chemical components (weight percent) are 10-15 percent of Al and 10-15 percent of Al₂O₃65-75% of aluminum slag powder, the balance of impurities and the granularity of less than 0.154 mm;

(2) 40-50% of aluminum slag powder and SiO₂30-40% of silica and/or silica sand with a content of more than 95%, Fe₃O₂10-20% of iron rust with the content of more than 90%, and carbon powder with the content of more than 85% of C, wherein the granularity of the silica and/or the silica sand is 3-6 mm, the granularity of the carbon powder is less than 0.104mm, and the addition amount of the carbon powder is 28-38% of the total weight of the aluminum slag powder, the iron rust, the silica and/or the silica sand;

(3) the aluminum slag powder, the rust, the silica and/or the silica sand and the carbon powder mixture are bonded together to form a blocky mixed molding by using waste heavy oil as a bonding agent, wherein the addition amount of the waste heavy oil is 5-15% of the total weight of the aluminum slag powder, the rust, the silica and/or the silica sand and the carbon powder;

(4) and putting the mixed formed product into a reaction furnace, and carrying out melting reduction reaction for 1-2 hours at the temperature of 1400-1800 ℃ so as to obtain the Al-Si-Fe alloy.

2. The method according to claim 1, wherein the sendust has the following chemical composition (in wt%): 40-45% of Al, 35-40% of Si and 15-25% of Fe.

3. The method according to claim 1 or 2, wherein the bulk blend molding has a particle size of 2 to 6cm, and the sendust alloy has a bulk particle size of 5 to 12 cm.