METHOD AND APPARATUS FOR TREATING IRON-CONTAINED RAW MATERIAL USING BATH SMELTING FURNACE

Abstract

The present invention relates to method and apparatus for treating iron-contained raw material using bath smelting furnace. An iron-contained raw material is mixed with a reducing agent. The mixture is added into a bath smelting furnace. The enriched oxygen is blown into the bath. The smelt is conducted at a temperature of 1200-1600 C. Compared with the traditional process of sintering/pellet-blast furnace smelting or rotary furnace reduction-electrical furnace smelting separation, the present invention has the remarkable advantages of short process, strong raw material adaptability, high product quality, low energy consumption, low pollution, etc. The present invention provides a new technology direction for effectively and comprehensively utilizing the iron-contained resource and has a wide application prospect.

Claims

1. A method for treating iron-contained raw material using bath smelting furnace, comprising: mixing an iron-contained raw material with a reducing agent to form a mixture; adding the mixture into a bath smelting furnace; blowing enriched oxygen into the bath; and smelting at a temperature of 1200-1600 C.

2. The method of claim 1, further comprising, adding an additive to the iron-contained raw material and the reducing agent to form the mixture; and adding the mixture into the bath smelting furnace for smelting; wherein the smelting time is 0.5-4 hours.

3. The method of claim 2, wherein, a mass ratio of the iron-contained raw material, the additive, and the reducing agent is 100:(0-60):(20-60).

4. The method of claim 2, wherein, the additive is one or more items selected from the group consisting of sodium carbonate, sodium sulfate, sodium chloride, sodium borate, sodium hydrogen carbonate, limestone, and dolomite.

5. The method of claim 1, wherein, the reducing agent is one or more items selected from the group consisting of anthracite, bitumite, a lignite, and a coke; and the mass ratio of the iron-contained raw material to the reducing agent is 100:(20-60).

6. The method of claim 1, wherein, the iron-contained raw material comprises TFe, V.sub.2O.sub.5, and TiO.sub.2; wherein a mass fraction of TFe is 30%-65%, a mass fraction of V.sub.2O.sub.5 is 0%-2.0%, and a mass fraction of TiO.sub.2 is 0%-35%.

7. The method of claim 1, wherein, an oxygen volume concentration of the enriched oxygen is 40%-80%. a molar ratio of oxygen atom in the enriched oxygen to carbon atom in the reducing agent is 0.4-1.0.

8. A bath smelting furnace apparatus for treating iron-contained raw material, comprising: an enriched oxygen tuyere arranged 0.3-0.6 m lower than a bath surface and on a sidewall of the bath; wherein, an iron-contained raw material is mixed with a reducing agent to form a mixture; the mixture is added into the bath smelting furnace apparatus; enriched oxygen is blown into the bath; and smelting is performed at a temperature of 1200-1600 C.

9. The bath smelting furnace apparatus of claim 8, wherein, a hearth is arranged 0.8-1.2 m lower than the enriched oxygen tuyere.

10. The bath smelting furnace apparatus of claim 8, further comprising: a steel water jacket, positioned at an upper portion of the bath furnace; a copper water jacket, positioned at a middle portion the bath furnace; and the hearth, positioned at a bottom portion of the bath furnace; wherein at least one of the copper water jacket and the steel water jacket is provided with a feed inlet; the steel water jacket is provided with a smoke outlet; a lower portion of the copper water jacket is provided with an enriched oxygen tuyere; an upper portion of the copper water jacket is provided with a secondary tuyere; the steel water jacket is provided with a tertiary tuyere; and a side wall of the hearth is provided with a slag outlet and a metal outlet.

11. The method of claim 3, wherein, the additive is one or more items selected from the group consisting of sodium carbonate, sodium sulfate, sodium chloride, sodium borate, sodium hydrogen carbonate, limestone, and dolomite.

12. The method of claim 2, wherein, the reducing agent is one or more items selected from the group consisting of anthracite, bitumite, a lignite, and a coke; and the mass ratio of the iron-contained raw material to the reducing agent is 100:(20-60).

13. The method of claim 6, wherein, an oxygen volume concentration of the enriched oxygen is 40%-80%. a molar ratio of oxygen atom in the enriched oxygen to carbon atom in the reducing agent is 0.4-1.0.

14. The bath smelting furnace apparatus of claim 9, further comprising: a steel water jacket, positioned at an upper portion of the bath furnace; a copper water jacket, positioned at a middle portion the bath furnace; and the hearth, positioned at a bottom portion of the bath furnace; wherein at least one of the copper water jacket and the steel water jacket is provided with a feed inlet; the steel water jacket is provided with a smoke outlet; a lower portion of the copper water jacket is provided with an enriched oxygen tuyere; an upper portion of the copper water jacket is provided with a secondary tuyere; the steel water jacket is provided with a tertiary tuyere; and a side wall of the hearth is provided with a slag outlet and a metal outlet.

15. The bath smelting furnace apparatus of claim 8, wherein, an additive is added to the iron-contained raw material and the reducing agent to form the mixture; and the mixture is added into the bath smelting furnace for smelting; wherein the smelting time is 0.5-4 hours.

16. The bath smelting furnace apparatus of claim 15, wherein, a mass ratio of the iron-contained raw material, the additive, and the reducing agent is 100:(0-60):(20-60).

17. The bath smelting furnace apparatus of claim 15, wherein, the additive is one or more items selected from the group consisting of sodium carbonate, sodium sulfate, sodium chloride, sodium borate, sodium hydrogen carbonate, limestone, and dolomite.

18. The bath smelting furnace apparatus of claim 16, wherein, the additive is one or more items selected from the group consisting of sodium carbonate, sodium sulfate, sodium chloride, sodium borate, sodium hydrogen carbonate, limestone, and dolomite.

19. The bath smelting furnace apparatus of claim 8, wherein, the reducing agent is one or more items selected from the group consisting of anthracite, bitumite, a lignite, and a coke; and the mass ratio of the iron-contained raw material to the reducing agent is 100:(20-60).

20. The bath smelting furnace apparatus of claim 15, wherein, the reducing agent is one or more items selected from the group consisting of anthracite, bitumite, a lignite, and a coke; and the mass ratio of the iron-contained raw material to the reducing agent is 100:(20-60).

21. The bath smelting furnace apparatus of claim 8, wherein, the iron-contained raw material comprises TFe, V.sub.2O.sub.5, and TiO.sub.2; wherein a mass fraction of TFe is 30%-65%, a mass fraction of V.sub.2O.sub.5 is 0%-2.0%, and a mass fraction of TiO.sub.2 is 0%-35%.

22. The bath smelting furnace apparatus of claim 8, wherein, an oxygen volume concentration of the enriched oxygen is 40%-80%. a molar ratio of oxygen atom in the enriched oxygen to carbon atom in the reducing agent is 0.4-1.0.

23. The bath smelting furnace apparatus of claim 21, wherein, an oxygen volume concentration of the enriched oxygen is 40%-80%. a molar ratio of oxygen atom in the enriched oxygen to carbon atom in the reducing agent is 0.4-1.0.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0043] FIG. 1 is an example of a process flowchart of the method for treating iron-contained raw material using bath smelting furnace of the present invention.

[0044] FIG. 2 is a front view of the bath smelting furnace apparatus of the present invention.

[0045] In the drawings, [0046] 1base; [0047] 2hearth; [0048] 3enriched oxygen tuyere; [0049] 4,5copper water jacket; [0050] 6secondary tuyere; [0051] 7feed inlet; [0052] 8tertiary tuyere; [0053] 9smoke outlet; [0054] 10steel water jacket; [0055] 17slag outlet; [0056] 18metal outlet.

DETAILED DESCRIPTION OF THE INVENTION

[0057] The present invention is further described by incorporating the specific embodiments hereinafter.

Embodiment 1

[0058] A side-blown furnace is designed wherein the dimension of the hearth is 14002600 mm, and the hearth area is 3.64 m.sup.2. Both sides of the furnace are respectively provided with four main tuyeres. The positions of the slag outlet and metal outlet are designed to ensure that the depth of the slag layer is 1000 mm and the depth of the metal layer is 300 mm. Four secondary tuyeres are provided 1200 mm above the liquid surface of the bath slag layer, respectively on both sides. Three tertiary tuyeres are provided 1000 mm above the secondary tuyeres, respectively on both sides. A feed inlet of 300 mm and a smoke outlet of 400400 mm are provided.

[0059] Test is carried out in the above bath smelting furnace.

[0060] One hundred parts of 1# iron-contained raw material are evenly mixed with twenty parts of dolomite and forty parts of coke in a rotary drum granulator. Water is added such that the moisture content of the material is 8%. The granules with a diameter range of 5 mm-10 mm are produced. The granulated material is added into the side-blown bath smelting furnace at a rate of five tons per hour. The smelting temperature is controlled within a range of 140050 C. The O.sub.2 concentration of the enriched oxygen blown in from the main tuyere is 60%. The pressure of the enriched oxygen is 0.6 MPa. The flow rate is 4000 Nm.sup.3/h. The smelting time is three hours. Under the above conditions, the reduction of iron, the smelting and separation of iron from slag can be achieved. The obtained pig iron grade is 94.5%, and the recovery rate of iron is 94.6%.

Embodiment 2

[0061] The bath smelting furnace is the same as that of the Embodiment 1.

[0062] One hundred parts of 2# iron-contained raw material and sixty parts of anthracite are added into the side-blown bath smelting furnace at a rate of six tons per hour. The smelting temperature is controlled within a range of 160050 C. The O.sub.2 concentration of the enriched oxygen blown in from the main tuyere is 80%. The pressure of the enriched oxygen is 0.7 MPa. The flow rate is 4500 Nm.sup.3/h. The smelting time is four hours. Under the above conditions, the reduction of iron, the smelting and separation of iron from slag can be achieved. The obtained pig iron grade is 92.3%, and the recovery rate of iron is 95.8%.

Embodiment 2 compared Embodiment 1

[0063] The bath smelting furnace is the same as that of the Embodiment 1.

[0064] One hundred parts of 2# iron-contained raw material, ten parts of sodium carbonate, and ten parts of coke are added into the side-blown bath smelting furnace at a rate of six tons per hour. The smelting temperature is controlled within a range of 130050 C. The O.sub.2 concentration of the enriched oxygen blown in from the main tuyere is 50%. The pressure of the enriched oxygen is 0.6 MPa. The flow rate is 4500 Nm.sup.3/h. The smelting time is four hours. Under the above conditions, the reduction of iron is not complete, and the smelting and separation effects of the iron from slag are not satisfactory. The situation where the slag contains iron is serious. The obtained pig iron grade is only 76.6%, and the recovery rate of iron is 64.0%.

Embodiment 3

[0065] The bath smelting furnace is the same as that of the Embodiment 1.

[0066] One hundred parts of 3# iron-contained raw material are evenly mixed with sixty parts of sodium carbonate and twenty parts of coke in a rotary drum granulator. Water is added such that the moisture content of the material is 8%. The granules with a diameter range of 5 mm-10 mm are produced. The granulated material is added into the side-blown bath smelting furnace at a rate of six tons per hour. The smelting temperature is controlled within a range of 130050 C. The O.sub.2 concentration of the enriched oxygen blown in from the main tuyere is 40%. The pressure of the enriched oxygen is 0.5 MPa. The flow rate is 4000 Nm.sup.3/h. The smelting time is three hours. Under the above conditions, the reduction of iron, and the smelting and separation of iron from slag can be achieved. The obtained pig iron grade is 95.8%, and the recovery rate of iron is 98.2%.

Embodiment 3 Compared Embodiment 2

[0067] The bath smelting furnace is the same as that of the embodiment 1.

[0068] One hundred parts of 3# iron-contained raw material are evenly mixed with thirty parts of sodium carbonate and twenty parts of coke in a rotary drum granulator. Water is added such that the moisture content of the material is 8%. The granules with a diameter range of 5 mm-10 mm are produced. The granulated material is added into the side-blown bath smelting furnace at a rate of six tons per hour. The smelting temperature is controlled within 1100 C. The O.sub.2 concentration of the enriched oxygen blown in from the main tuyere is 50%. The pressure of the enriched oxygen is 0.5 MPa. The flow rate is 4000 Nm.sup.3/h. The smelting time is three hours. Under the above conditions, the products of iron and slag cannot be effectively obtained. The smelting process fails.

Embodiment 4

[0069] The bath smelting furnace is the same as that of the embodiment 1.

[0070] One hundred parts of 4# iron-contained raw material are evenly mixed with thirty parts of sodium sulfate and forty parts of coke in a rotary drum granulator. Water is added such that the moisture content of the material is 8%. The granules with a diameter ranged of 5 mm-10 mm are produced. The granulated material is added into the side-blown bath smelting furnace at a rate of five tons per hour. The smelting temperature is controlled within a range of 150050 C. The O.sub.2 concentration of the enriched oxygen blown in from the main tuyere is 70%. The pressure of the enriched oxygen is 0.7 MPa. The flow rate is 4500 Nm.sup.3/h. The smelting time is four hours. Under the above conditions, the reduction of iron, the smelting and separation of iron from slag can be achieved. The obtained pig iron grade is 92.5%, and the recovery rate of iron is 96.0%.

Embodiment 4 as Compared Embodiment 3

[0071] The bath smelting furnace is the same as that of the Embodiment 1.

[0072] One hundred parts of 4# iron-contained raw material are evenly mixed with eighty parts of sodium carbonate and ten parts of anthracite in a rotary drum granulator. Water is added such that the moisture content of the material is 8%. The granule with a diameter ranged of 5 mm-10 mm are produced. The granulated material is added into the side-blown bath smelting furnace at a rate of five tons per hour. The smelting temperature is controlled within a range of 130050 C. The O.sub.2 concentration of the enriched oxygen blown in from the main tuyere is 70%. The pressure of the enriched oxygen is 0.7 MPa. The flow rate is 4500 Nm.sup.3/h. The smelting time is four hours. Under the above conditions, the products of iron and slag cannot be effectively obtained. The smelting process fails.

TABLE-US-00001 TABLE 1 Main Chemical Compositions of the Four Iron-Contained Raw Materials in the Embodiments/wt. % Ore sample number TFe TiO.sub.2 V.sub.2O.sub.5 SiO.sub.2 Al.sub.2O.sub.3 CaO MgO 1 55.33 9.65 1.95 4.60 4.52 2.01 0.60 2 64.78 0.12 0.03 2.13 2.65 1.01 0.57 3 30.06 34.67 1.03 14.37 3.02 6.95 1.29 4 45.38 18.58 1.52 8.66 2.56 3.27 0.88

[0073] Moreover, the present invention may also have a variety of embodiments. Artisans who are familiar with the art can make various corresponding modifications and variations based on the disclosure of the present invention without departing from the spirit and substance of the present invention. However, the corresponding modifications and variations should belong to the protective scope of the appended claims.