WO2012130091A1

WO2012130091A1 - Iron ore reducing agent, iron ore mixture, and method for reducing iron ore

Info

Publication number: WO2012130091A1
Application number: PCT/CN2012/072881
Authority: WO
Inventors: 韩谊; 李家华; 陆安
Original assignee: 朗威资源有限公司
Priority date: 2011-03-25
Filing date: 2012-03-23
Publication date: 2012-10-04
Also published as: CN102690920A

Abstract

An iron ore reducing agent comprising an amorphous carbon of eight to 35 parts by weight and calcium oxide of four to 35 parts by weight. Also provided are an iron ore mixture and a method for reducing iron ore.

Description

Iron ore reducing agent, iron ore mixture and method for reducing iron ore

The present application relates to an iron ore reducing agent comprising 8 - 35 parts by weight of amorphous carbon and 4 - 35 parts by weight of calcium oxide. The application also relates to an iron ore mixture comprising the iron ore reducing agent and a method of reducing iron ore using the iron ore reducing agent. Background technique

In general, iron ore is classified into magnetite, hematite, illusion or semi-artificial hematite, vanadium-titanium magnetite ore, limonite ore, siderite according to the type of iron-bearing minerals. A mixed ore composed of two or more kinds of iron-containing minerals. Iron ore can also be classified into high-sulfur iron ore, low-sulfur iron ore, high-phosphorus iron ore, low-phosphorus iron ore according to impurities.

In general, it is desirable to use iron ore iron having a high iron content and a small impurity content. However, for favorable impurities contained in iron ore, such as titanium, it is desirable to have a higher content. For example, red nickel ore is a type of nickel deposit, which is a weathering product of nickel-bearing rock mass, distributed on the earth's surface, and the ore is red earthy soil. The nickel is nickel oxide, and the particle size is very finely adsorbed on the loess. It can't be enriched, and it needs to be treated by the whole rock mine. Therefore, the amount of nickel contained is the primary condition for development and utilization. The red earth nickel ore resources in Indonesia and the Philippines are very rich. In recent years, many units in China have imported the mine for small blast furnace smelting to take its ferronickel, which is used to refine stainless steel. However, the desired laterite nickel ore is selected to have a grade nickel content of ≥1.7%, and few people below this value are questioned.

Similarly, for ilmenite, ore having a Ή02 content of 47-52% is generally used. For titanium magnetite with a Ή02 content of 8 to 15%, if it is used as iron ore, the content of Ή02 is too high, which is unacceptable to iron-making enterprises. The production of synthetic rutile, white titanium powder, reduction of ilmenite, high titanium slag is not applicable, therefore, such resources are difficult to use. The Indonesian island country is rich in such low-titanium-titanium magnetite. Because there is no suitable method for selecting and smelting, the resources have not been exploited.

In addition, some iron ore is not suitable for iron making. For example, specularite is a kind of hematite. It is a scaly structure, which is not conducive to sintering, pellets and agglomeration. Therefore, the world's blast furnace ironmaking system has always been unable to use mirrors. Iron ore is used alone in blast furnace ironmaking.

At present, China's steel output has exceeded 500 million tons. However, more than 52% of the required iron ore is supported by imports. Iron ore prices are rising, iron ore resources are in short supply, and there is an urgent need to expand iron ore resources to supplement China's iron. Required for the mining market. Therefore, if the above-mentioned iron ore that cannot be utilized can be effectively utilized, huge economic and social benefits will be generated. Summary of the invention

The present application has developed an effective reducing agent for iron ore that cannot be effectively utilized in the prior art, and obtains iron and corresponding titanium or nickel by a non-blast furnace smelting method.

The present application relates to an iron ore reducing agent comprising 8-35 parts by weight of amorphous carbon and 4 - 35 parts by weight of calcium oxide.

The application also relates to an iron ore mixture comprising the iron ore reducing agent and to a method of reducing iron ore. Specifically, the present application relates to the following technical solutions:

Technical Solution 1. An iron ore reducing agent comprising 8-35 parts by weight of amorphous carbon and 4 to 35 parts by weight of calcium oxide.

2. The iron ore reducing agent of the first aspect, wherein the amorphous carbon is 8 to 29 parts by weight and the calcium oxide is 14 to 29 parts by weight; preferably, the amorphous carbon is 10 to 15 parts by weight, and the calcium oxide is 15 to 22 Parts by weight.

3. The iron ore reducing agent of the first aspect, wherein the amorphous carbon is 8 to 29 parts by weight and the calcium oxide is 4 to 29 parts by weight; preferably, the amorphous carbon is 8 to 15 parts by weight, and the calcium oxide is 4 to 9 Parts by weight.

4. The iron ore reducing agent of the first aspect, wherein the amorphous carbon is 13 to 34 parts by weight and the calcium oxide is 9 to 31 parts by weight; preferably, the amorphous carbon is 13 to 17 parts by weight, and the calcium oxide is 9 to 13 Parts by weight.

5. The iron ore reducing agent according to any one of claims 1 to 4, wherein the amorphous carbon is provided in the form of anthracite, the fixed carbon content of the anthracite is 70% by weight, preferably the fixed carbon content of anthracite

>75% by weight, based on the weight of anthracite.

6. The iron ore reducing agent according to any one of claims 1 to 5, wherein the calcium oxide is provided in the form of lime, the calcium oxide content of the lime is >75% by weight, preferably the calcium oxide content of the lime is >80% by weight, based on The weight of lime.

7. The iron ore reducing agent according to any one of claims 1 to 6, wherein the amorphous carbon has a particle size of 48 mesh or finer, preferably 200 mesh or finer; and the calcium oxide has a particle size of 150 mesh or finer, preferably 200 mesh. Or thinner.

8. The iron ore reducing agent according to any one of claims 1 to 7, wherein the iron ore is selected from the group consisting of nickel red iron ore, mirror iron ore and 4 too magnetite.

9. The iron ore reducing agent of claim 8 wherein said nickel red iron ore has a nickel content of less than 1.7% by weight, and a total iron content of > 35 weight percent, based on the weight of the nickel red iron ore; wherein said mirror The total iron content of the iron ore is > 35 wt%, based on the weight of the specular iron ore; wherein the titanomagnetite has a titanium dioxide content of 8-15% by weight, and the total iron content is > 35 wt%, based on the titanium magnet The weight of the mine.

10. The iron ore reducing agent according to any one of claims 1-9, wherein the iron ore reducing agent is composed of anthracite and lime.

11. An iron ore mixture comprising 100 parts by weight of iron ore, 8 to 35 parts by weight of amorphous carbon and 4 to 35 parts by weight of calcium oxide.

12. The iron ore mixture of claim 11, wherein the iron ore is 100 parts by weight; the amorphous carbon is 8 - 29 parts by weight and the calcium oxide is 14 - 29 parts by weight; preferably the amorphous carbon is 10 - 15 parts by weight, And the calcium oxide is 15-22 parts by weight.

13. The iron ore mixture of claim 11, wherein the iron ore is 100 parts by weight; the amorphous carbon is 8 to 29 parts by weight and the calcium oxide is 4 to 29 parts by weight; preferably the amorphous carbon is 8 to 15 parts by weight. And the calcium oxide is 4-9 parts by weight.

14. The iron ore mixture of claim 11, wherein the iron ore is 100 parts by weight; the amorphous carbon is 13 - 34 parts by weight and the calcium oxide is 9 - 31 parts by weight; preferably the amorphous carbon is 13 - 17 parts by weight, And the calcium oxide is 9-13 parts by weight.

The iron ore mixture according to any one of claims 11 to 14, wherein the amorphous carbon is provided in the form of anthracite, the fixed carbon content of the anthracite is 70% by weight, preferably the fixed carbon content of the anthracite is >75% by weight, based on The weight of anthracite.

16. The iron ore mixture according to any one of claims 11 to 15, wherein the calcium oxide is provided in the form of lime, the calcium oxide content of the lime is >75% by weight, preferably the calcium oxide content of the lime is >80% by weight, based on lime the weight of.

17. The iron ore mixture according to any one of claims 11 to 16, wherein the iron ore has a particle size of 1 mm or less; the amorphous carbon has a particle size of 48 mesh or finer, preferably 200 mesh or finer; The particle size is 150 mesh or finer, preferably 200 mesh or finer.

18. The iron ore mixture of any one of claims 11-17, wherein the iron ore is selected from the group consisting of nickel red Iron ore, mirror iron ore or 4 too magnetite.

19. The iron ore mixture of claim 18, wherein the nickel red iron ore has a nickel content of less than 1.7 wt%, and a total iron content of > 35 wt%, based on the weight of the nickel red iron ore; wherein the mirror iron The total iron content of the ore is >35 wt%, based on the weight of the specular iron ore; wherein the titanomagnetite has a titanium dioxide content of 8-15 wt%, and the total iron content is "35 wt%", based on titanomagnetite the weight of.

20. The iron ore mixture of any one of clauses 11 to 19, wherein the iron ore mixture is comprised of iron ore, anthracite, and lime.

21. A method of reducing iron ore comprising the steps of:

Mixing step: mixing 100 parts by weight of iron ore, 8-35 parts by weight of amorphous carbon and 4 -

35 parts by weight of calcium oxide to obtain an iron ore mixture;

Reaction step: The above iron ore mixture is reacted at a temperature of from 1100 to 1450 °C.

22. The method of claim 21, wherein the temperature of the reaction step is from 1180 to 1300 ° C, preferably from 1200 to 1300 ° C.

23. The method of claim 21 or 22, wherein the reacting step is carried out for 30 to 120 minutes, preferably 80 to 110 minutes.

The method of any one of claims 21 to 23, wherein the reacting step is carried out in a reducing atmosphere.

The method of any one of claims 21 to 24, wherein the iron ore is 100 parts by weight; the amorphous carbon is 8 to 29 parts by weight and the calcium oxide is 14 to 29 parts by weight; preferably the amorphous carbon is 10 to 15 parts by weight. Parts, and calcium oxide is 15-22 parts by weight.

26. The method of any one of claims 21 to 24, wherein the iron ore is 100 parts by weight; the amorphous carbon is 8-29 parts by weight and the calcium oxide is 4-29 parts by weight; preferably the amorphous carbon is 8 - 15 parts by weight. And calcium oxide is 4-9 parts by weight.

27. The method of any one of claims 21 to 24, wherein the iron ore is 100 parts by weight; the amorphous carbon is 13 - 34 parts by weight and the calcium oxide is 9 - 31 parts by weight; preferably the amorphous carbon is 13 - 17 parts by weight. And calcium oxide is 9-13 parts by weight.

The method of any one of claims 21 to 24, wherein the amorphous carbon is provided in the form of anthracite, the fixed carbon content of the anthracite is 70% by weight, preferably the fixed carbon content of the anthracite, 75 wt%, based on the weight of the anthracite .

29. The method of any one of claims 21-28, wherein the calcium oxide is provided in the form of lime, The lime has a calcium oxide content of >75% by weight, preferably lime with a calcium oxide content of >80% by weight, based on the weight of the lime.

30. The method of any one of claims 21 to 29, wherein the iron ore has a particle size of 1 mm or less; the amorphous carbon has a particle size of 48 mesh or finer, preferably 200 mesh or finer; and the calcium oxide has a particle size of 150 The order is finer or finer, preferably 200 mesh or finer.

The method of any one of claims 21 to 30, wherein the iron ore is selected from the group consisting of nickel red iron ore, mirror iron or ore magnetite.

The method of claim 31, wherein the nickel red iron ore has a nickel content of less than 1.7% by weight, and a total iron content of > 35 wt%, based on the weight of the nickel red iron ore; wherein the total of the specular iron ore The iron content is > 35 wt%, based on the weight of the specularite; wherein the titano-magnetite has a titanium dioxide content of 8 - 15% by weight, and a total iron content of > 35 wt%, based on the weight of the titano-magnetite.

The method of any one of claims 21 to 32, wherein the method further comprises preheating the mixture at a temperature of 200 to 1100 ° C for 2 to 5 hours between the mixing step and the reaction step.

The method of any one of claims 21 to 33, wherein the reacting step is carried out in an apparatus selected from the group consisting of a rotary hearth furnace, a rotary kiln, a tunnel kiln, and a raceway kiln.

The method of any one of claims 21 to 34, wherein the iron ore mixture is composed of iron ore, anthracite, and lime.

The method of any one of claims 21 to 35, wherein the step of reacting is carried out at ambient pressure. DETAILED DESCRIPTION OF THE INVENTION Definition of terms

This application uses some terms which will have the following meanings.

Amorphous carbon: refers to a pure amorphous carbon element, which may be provided in the form of charcoal, coal, coke, and the like in the present application.

Fixed carbon: The residue after removing moisture, ash, and volatiles from coal.

Total iron content: refers to the sum of all iron elements in iron ore. In general, it can be measured according to GB/T 6730.65-2009 Determination of total iron content of iron ore by titanium trichloride reduction potassium dichromate titration (conventional method:).

Reducing atmosphere: It means to maintain a weak reducing atmosphere when reducing iron ore. Contains a small amount of carbon monoxide. In the test, the control air volume (controlling the oxygen supply amount) is usually adopted so that the combustion flame in the kiln is orange instead of blue, thereby ensuring a reducing atmosphere. Here, in order to control the reducing atmosphere, the amount of CO generated by the combustion of the fuel is 4 , small and can be ignored. A first aspect of the present application relates to a first aspect of the present application to an iron ore reducing agent comprising 8 to 35 parts by weight of amorphous carbon and 4 to 35 parts by weight of calcium oxide.

Applicants of the present application have found that iron ore resources that are not fully utilized in the prior art can be used when using an iron ore reducing agent comprising 8 to 35 parts by weight of amorphous carbon and 4 to 35 parts by weight of calcium oxide. Make full use of it to get iron.

In the embodiment of the first aspect of the present application, in the iron ore reducing agent, the amount of amorphous carbon may be 8 to 29 parts by weight and the calcium oxide is 14 to 29 parts by weight; preferably, the amount of amorphous carbon may be 10 - 15 parts by weight, and calcium oxide is 15-22 parts by weight. In the embodiment of the first aspect of the present application, in the iron ore reducing agent, the amount of amorphous carbon may be 8-29 parts by weight and the calcium oxide is 4-29 parts by weight; preferably, the amount of amorphous carbon may be 8 - 15 parts by weight, and calcium oxide is 4-9 parts by weight. In the embodiment of the first aspect of the present application, in the iron ore reducing agent, the amount of amorphous carbon may be 13-34 parts by weight and the calcium oxide is 9-31 parts by weight; preferably, the amount of amorphous carbon may be 13 - 17 parts by weight, and calcium oxide is 9 - 13 parts by weight.

Those skilled in the art will appreciate that the composition of the iron ore reductant of the present application will be slightly different for different iron ores, but it does not exceed 8 to 35 parts by weight of amorphous carbon and 4 to 35 parts by weight of oxidation. The range of calcium. Specifically, for example, in the embodiment of the first aspect of the present application, the iron ore reducing agent of the first aspect of the present application may include 8 to 29 parts by weight of amorphous carbon and 14 when used for nickel red iron ore. -29 parts by weight of calcium oxide; preferably comprising 10-15 parts by weight of amorphous carbon and 15-22 parts by weight of calcium oxide.

In an embodiment of the first aspect of the present application, the iron ore reducing agent of the first aspect of the present application may comprise 8 to 29 parts by weight of amorphous carbon and 4 to 29 parts by weight of calcium oxide when used in the form of specular iron ore. It preferably comprises 8 to 15 parts by weight of amorphous carbon and 4 to 9 parts by weight of calcium oxide.

In an embodiment of the first aspect of the present application, the iron ore reducing agent of the first aspect of the present application may comprise 13 to 34 parts by weight of amorphous carbon and 9 to 31 parts by weight of oxidation when used in titanomagnetite. Calcium; preferably comprises 13 - 17 parts by weight of amorphous carbon and 9 - 13 parts by weight of calcium oxide. In the first aspect of the present application, the amorphous carbon may be provided in various forms such as charcoal, coal, and coke. Among them, coal is considered, and anthracite is more preferably used in consideration of cost efficiency factors. Thus, in an embodiment of the first aspect of the application, the amorphous carbon is provided in the form of anthracite. The present application is not particularly limited to anthracite, but in order to achieve a better effect, the fixed carbon content of the anthracite is preferably 70% by weight, more preferably the fixed carbon content of anthracite is 75% by weight, based on the weight of the anthracite. Other indicators of anthracite can also be controlled as needed to achieve the best results. For example, in a preferred embodiment of the first aspect of the present application, the anthracite has an ash content of less than or equal to 20% by weight, and/or a sulfur content of less than or equal to 0.5% by weight based on the weight of the anthracite. In the first aspect of the application, pure calcium oxide can be used. However, calcium oxide in the form of lime can also be used in consideration of cost efficiency factors. Thus, in an embodiment of the first aspect of the application, the calcium oxide is provided in the form of lime. The present application is not particularly limited to lime, but in order to achieve a better effect, it is preferred that the lime has a calcium oxide content of > 75 wt%, more preferably a lime oxide content of lime > 80 wt%, based on the weight of the lime. Other indicators of lime can also be controlled as needed to achieve optimum results. For example, in a preferred embodiment of the first aspect of the present application, the content of silica in the lime is less than or equal to 3% by weight based on the weight of the lime. In the first aspect of the present application, the respective components in the iron ore reducing agent may be in various solid forms, but in view of better participation in the reduction reaction, it is preferred that both the amorphous carbon and the calcium oxide are in the form of pellets. In a preferred embodiment of the first aspect of the present application, the amorphous carbon has a particle size of 48 mesh or finer, preferably 200 mesh or finer; and the calcium oxide has a particle size of 150 mesh or finer, preferably 200 mesh or more. fine. After limiting the particle size of amorphous carbon and calcium oxide, correspondingly, if anthracite is used to provide amorphous carbon and lime is used to provide calcium oxide, the same requirements are required for the particle size of the anthracite and lime. That is, in the preferred embodiment of the first aspect of the present application, if anthracite and lime are used, the anthracite has a particle size of 48 mesh or finer, preferably 200 mesh or finer; and the lime has a particle size of 150 mesh or More fine, preferably 200 mesh or finer. The iron ore reducing agent of the first aspect of the present application can be used for the reduction of various iron ores, but it is preferred that the iron ore reducing agent is used for nickel red iron ore, mirror iron or titanium magnetite. In a preferred embodiment of the first aspect of the present application, the nickel red iron ore has a nickel content of less than 1.7% by weight, and a total iron content of > 35 wt%, preferably a total iron content of > 40 wt%, based on nickel red The weight of iron ore. In the application In a preferred embodiment of the invention, the total iron content of the specularite is > 35 wt%, preferably the total iron content is > 40 wt%, based on the weight of the pyrite. In a preferred embodiment of the first aspect of the present application, the titanomagnetite has a titanium dioxide content of 8 to 15% by weight, and a total iron content of 3% by weight, preferably a total iron content of >40% by weight, based on titanium The weight of magnetite.

Other indicators of iron ore can also be controlled as needed to achieve the best results. For example, in the embodiment of the first aspect of the present application, it is preferred that the specular iron has a sulfur content of 0.2% by weight or less, and/or the phosphorus content is 0.2% by weight or less based on the total amount of the specular iron ore. In a preferred embodiment of the first aspect of the application, the iron ore reducing agent consists of anthracite and lime. Second Aspect of the Present Application A second aspect of the present application relates to an iron ore mixture comprising 100 parts by weight of iron ore, 8 - 35 parts by weight of amorphous carbon and 4 - 35 parts by weight of calcium oxide.

In an embodiment of the second aspect of the present application, the iron ore mixture comprises: 100 parts by weight of iron ore; 8-29 parts by weight of amorphous carbon and 14-29 parts by weight of calcium oxide, preferably 10-15 parts by weight Amorphous carbon, and 15 - 22 parts by weight of calcium oxide.

In an embodiment of the second aspect of the present application, the iron ore mixture comprises: 100 parts by weight of iron ore; 8 to 29 parts by weight of amorphous carbon and calcium oxide of 4 to 29 parts by weight, preferably 8 to 15 parts by weight. Amorphous carbon and 4-9 parts by weight of calcium oxide.

In an embodiment of the second aspect of the present application, the iron ore mixture comprises: 100 parts by weight of iron ore; 13-34 parts by weight of amorphous carbon and 9-31 parts by weight of calcium oxide; preferably 13 - 17 parts by weight Amorphous carbon and 9-13 parts by weight of calcium oxide.

In an embodiment of the second aspect of the present application, the present application relates to an iron ore mixture which may include 100 parts by weight of nickel red iron ore, 8 to 29 parts by weight of amorphous carbon, and 14 to 29 parts by weight of oxidation. Calcium; preferably comprises 10 to 15 parts by weight of amorphous carbon and 15 to 22 parts by weight of calcium oxide.

In an embodiment of the second aspect of the present application, the present application relates to an iron ore mixture which may comprise 100 parts by weight of specularite, 8-29 parts by weight of amorphous carbon and 4-29 parts by weight of oxidation. Calcium; preferably comprises 8 to 15 parts by weight of amorphous carbon and 4 to 9 parts by weight of calcium oxide.

In an embodiment of the second aspect of the present application, the present application relates to an iron ore mixture, which To include 100 parts by weight of titanium magnetite, 13 - 34 parts by weight of amorphous carbon and 9 - 31 parts by weight of calcium oxide; preferably comprising 13 - 17 parts by weight of amorphous carbon and 9 - 13 parts by weight of calcium oxide . In the second aspect of the present application, the amorphous carbon may be provided in various forms such as charcoal, coal, and coke. Among them, coal is considered, and anthracite is more preferably used in consideration of cost efficiency factors. Thus, in an embodiment of the second aspect of the application, the amorphous carbon is provided in the form of anthracite. The present application is not particularly limited to anthracite, but in order to achieve a better effect, the fixed carbon content of the anthracite is preferably 70% by weight, more preferably the fixed carbon content of anthracite is 75% by weight, based on the weight of the anthracite. Other indicators of anthracite can also be controlled as needed to achieve the best results. For example, in a preferred embodiment of the second aspect of the present application, the anthracite has an ash content of 20% by weight or less, and/or a sulfur content of 0.5% by weight or less based on the weight of the anthracite. In the second aspect of the application, pure calcium oxide can be used. However, calcium oxide in the form of lime can also be used in consideration of cost efficiency factors. Thus, in an embodiment of the second aspect of the application, the calcium oxide is provided in the form of lime. The present application is not particularly limited to lime, but in order to achieve a better effect, it is preferred that the lime has a calcium oxide content of > 75 wt%, more preferably a lime oxide content of lime > 80 wt%, based on the weight of the lime. Other indicators of lime can also be controlled as needed to achieve optimum results. For example, in a preferred embodiment of the second aspect of the present application, the content of silica in the lime is less than or equal to 3% by weight based on the weight of the lime. In the second aspect of the application, the individual components in the iron ore mixture may be in various solid forms, but in view of better participation in the reduction reaction, it is preferred that the iron ore, amorphous carbon and calcium oxide are all pellets. form. In a preferred embodiment of the second aspect of the present application, the iron ore has a particle size of 1 mm or less; the amorphous carbon has a particle size of 48 mesh or finer, preferably 200 mesh or finer; and the calcium oxide has a particle size of 150 The order is finer or finer, preferably 200 mesh or finer. After limiting the particle size of amorphous carbon and calcium oxide, correspondingly, if anthracite is used to provide amorphous carbon and lime is used to provide calcium oxide, the same requirements are required for the particle size of the anthracite and lime. That is, in the preferred embodiment of the second aspect of the present application, if anthracite and lime are used, the anthracite has a particle size of 48 mesh or finer, preferably 200 mesh or finer; and the lime has a particle size of 150 mesh or More fine, preferably 200 mesh or finer. The iron ore in the iron ore mixture of the second aspect of the present application may be various iron ore, but preferably, the iron ore is nickel red iron ore, mirror iron or titanomagnetite. In a preferred embodiment of the second aspect of the present application, the nickel red iron ore has a nickel content of less than 1.7% by weight, and a total iron content of > 35 wt%, preferably a total iron content of > 40 wt%, based on nickel red The weight of iron ore. In a preferred embodiment of the second aspect of the application, the total iron content of the specularite is > 35 wt%, preferably the total iron content is > 40 wt%, based on the weight of the specular iron ore. In a preferred embodiment of the second aspect of the present application, the titanomagnetite has a titanium dioxide content of 8 to 15% by weight, and a total iron content of > 35 wt%, preferably a total iron content of > 40 wt%, based on titanium The weight of magnetite.

In general, for all iron ore, the total iron content may range from 38% to 62% by weight, based on the weight of the iron ore.

Other indicators of iron ore can also be controlled as needed to achieve the best results. For example, in the embodiment of the second aspect of the present application, it is preferred that the specular iron has a sulfur content of 0.2% by weight or less, and/or the phosphorus content is 0.2% by weight or less based on the total amount of the specular iron ore.

Further, in the embodiment of the second aspect of the present application, the iron ore may optionally be subjected to beneficiation treatment to obtain and use "concentrate", particularly ore having a total iron content of > 40% by weight.

In a preferred embodiment of the second aspect of the application, the iron ore mixture consists of iron ore, anthracite and lime.

The iron ore mixture of the second aspect of the present application can be directly reduced to obtain iron. A third aspect of the present application relates to a method of reducing iron ore comprising the steps of: mixing step: mixing 100 parts by weight of iron ore, 8 - 35 parts by weight of amorphous carbon and 4 - 35 parts by weight of calcium oxide to obtain an iron ore mixture;

Reaction step: The above iron ore mixture is reacted at a temperature of from 1100 to 1450 °C. Using the method of the third aspect of the present application, iron ore, particularly nickel-iron ore, specularite or titano-magnetite, which cannot be fully and efficiently utilized in the prior art, can be reduced to non-blast furnace ironmaking conditions. iron. The third aspect of the present application has no particular limitation on the mixing step, as long as the iron ore can be determined. The carbon and calcium oxide can be mixed evenly. This mixing can be carried out using any mixing device known in the art. Mixing can also be carried out at normal temperature and pressure. In the embodiment of the third aspect of the present application, it is preferred that the temperature of the reaction step is from 1180 to 1300 °C, more preferably from 1200 to 1300 °C.

In the third aspect of the present application, there is no particular requirement for the time during which the reaction step is carried out. In general, the reaction time is related to the specific iron ore and the reaction temperature used. However, in general, the reaction step can be carried out for 30 to 120 minutes, preferably 80 to 110 minutes. In the method of the third aspect of the present application, the reaction step may be carried out under a closed condition, and may be carried out, for example, under ambient pressure, generally under normal pressure. In order to obtain an optimum reduction yield, a weak reducing atmosphere can be employed in the reaction step. Namely, the amount of air (controlling the amount of oxygen supplied) is controlled so that the combustion flame in the reaction apparatus is orange instead of blue, thereby ensuring that the reaction step is carried out under a reducing atmosphere. In the method of the third aspect of the present application, the reaction apparatus used for carrying out the reaction step is not particularly limited. In an embodiment of the third aspect of the application, the reaction step can be carried out in an apparatus selected from the group consisting of a rotary hearth furnace, a rotary kiln, a tunnel kiln, and a raceway kiln. In addition, depending on the actual situation, it may be necessary to preheat the iron ore mixture obtained in the mixing step before the reaction step. In an embodiment of the third aspect of the present application, the method further comprises preheating the mixture at a temperature of 200 to 1100 ° C for 2 to 5 hours, preferably 3 to 4 hours, between the mixing step and the reaction step. At this time, the preheating can be prepared for the temperature to enter the reduction reaction. Preheating can be carried out under normal pressure conditions.

There is no limitation on the heating fuel which obtains the desired temperature in the reaction step and/or the preheating step, and it may be bituminous coal, heavy oil, natural gas, liquefied gas, coking gas, blast furnace gas or the like.

In an embodiment of the third aspect of the present application, in the mixing step of the method, the iron ore is

100 parts by weight; amorphous carbon is 8 - 29 parts by weight and calcium oxide is 14 - 29 parts by weight; preferably amorphous carbon is 10 - 15 parts by weight, and calcium oxide is 15 - 22 parts by weight. In an embodiment of the third aspect of the present application, in the mixing step of the method, the iron ore is 100 parts by weight; the amorphous carbon is 8 to 29 parts by weight and the calcium oxide is 4 to 29 parts by weight; preferably amorphous carbon 8 to 15 parts by weight, And the calcium oxide is 4 - 9 parts by weight. In an embodiment of the third aspect of the present application, in the mixing step of the method, the iron ore is 100 parts by weight; the amorphous carbon is 13 - 34 parts by weight and the calcium oxide is 9 - 31 parts by weight; preferably amorphous carbon It is 13 - 17 parts by weight, and the calcium oxide is 9 - 13 parts by weight.

In an embodiment of the third aspect of the present application, the mixing step of the method comprises mixing 100 parts by weight of nickel red iron ore, 8 to 29 parts by weight of amorphous carbon, and 14 to 29 parts by weight of calcium oxide; preferably mixing 100 The iron ore mixture is obtained in parts by weight of nickel red iron ore, 10 - 15 parts by weight of amorphous carbon and 15 - 22 parts by weight of calcium oxide.

In an embodiment of the third aspect of the present application, the mixing step of the method comprises mixing 100 parts by weight of specularite, 8 to 29 parts by weight of amorphous carbon and 4 to 29 parts by weight of calcium oxide; preferably comprising mixing 100 The iron ore mixture is obtained in parts by weight of specular iron ore, 8 - 15 parts by weight of amorphous carbon and 4 - 9 parts by weight of calcium oxide.

In an embodiment of the third aspect of the present application, the mixing step of the method comprises mixing 100 parts by weight of titanomagnetite, 13 - 34 parts by weight of amorphous carbon and 9 - 31 parts by weight of calcium oxide; preferably including mixing 100 parts by weight of titanium magnetite, 13 - 17 parts by weight of amorphous carbon and 9 - 13 parts by weight of calcium oxide are used to obtain an iron ore mixture.

In the third aspect of the present application, the amorphous carbon may be provided in various forms such as charcoal, coal, and coke. Among them, coal is considered, and anthracite is more preferably used in consideration of cost efficiency factors. Thus, in an embodiment of the third aspect of the application, the amorphous carbon is provided in the form of anthracite. The present application is not particularly limited to anthracite, but in order to achieve a better effect, the fixed carbon content of the anthracite is preferably 70% by weight, more preferably the fixed carbon content of anthracite is 75% by weight, based on the weight of the anthracite. Other indicators of anthracite can also be controlled as needed to achieve the best results. For example, in a preferred embodiment of the third aspect of the present application, the anthracite has an ash content of 20% by weight or less, and/or a sulfur content of 0.5% by weight or less based on the weight of anthracite. In the third aspect of the application, pure calcium oxide can be used. However, calcium oxide in the form of lime can also be used in consideration of cost efficiency factors. Thus, in an embodiment of the third aspect of the application, the calcium oxide is provided in the form of lime. The present application is not particularly limited to lime, but in order to achieve a better effect, it is preferred that the lime has a calcium oxide content of > 75 wt%, more preferably a lime oxide content of lime > 80 wt%, based on the weight of the lime. Other indicators of lime can also be controlled as needed to achieve optimum results. For example, in a preferred embodiment of the third aspect of the present application, stone In the ash, the content of silica is less than or equal to 3% by weight based on the weight of the lime. In the third aspect of the present application, iron ore, amorphous carbon and calcium oxide may be in various solid forms, but in view of better participation in the reaction, it is preferred that the iron ore, amorphous carbon and calcium oxide are in the form of pellets. . In a preferred embodiment of the third aspect of the present application, the iron ore has a particle size of 1 mm or less; the amorphous carbon has a particle size of 48 mesh or finer, preferably 200 mesh or finer; and the calcium oxide has a particle size of 150 The order is finer or finer, preferably 200 mesh or finer. After limiting the particle size of amorphous carbon and calcium oxide, correspondingly, if anthracite is used to provide amorphous carbon and lime is used to provide calcium oxide, the same requirements are required for the particle size of the anthracite and lime. That is, in the preferred embodiment of the third aspect of the present application, if anthracite and lime are used, the anthracite has a particle size of 48 mesh or finer, preferably 200 mesh or finer; and the lime has a particle size of 150 mesh or More fine, preferably 200 mesh or finer. The iron ore used in the third aspect of the present application may be various iron ore, but preferably, the iron ore is nickel red iron ore, mirror iron or titanomagnetite. In a preferred embodiment of the third aspect of the present application, the nickel red iron ore has a nickel content of less than 1.7% by weight, and a total iron content of > 35 wt%, preferably a total iron content of > 40 wt%, based on nickel red The weight of iron ore. In a preferred embodiment of the third aspect of the present application, the total iron content of the specularite is > 35 wt%, preferably the total iron content is > 40 wt%, based on the weight of the specular iron ore. In a preferred embodiment of the third aspect of the present application, the titanomagnetite has a titanium dioxide content of 8 to 15% by weight, and a total iron content of >35 wt%, preferably a total iron content of 40% by weight, based on titanium The weight of magnetite.

Other indicators of iron ore can also be controlled as needed to achieve the best results. For example, in the embodiment of the third aspect of the present application, it is preferred that the specular iron has a sulfur content of 0.2% by weight or less, and/or a phosphorus content of 0.2% by weight or less based on the total amount of the specular iron ore.

Further, in the embodiment of the third aspect of the present application, the iron ore may optionally be subjected to a beneficiation treatment to obtain and use "concentrate", particularly ore having a total iron content of > 40% by weight. For the product obtained after the reaction step, pulverization and magnetic separation can be carried out to obtain reduced iron powder. It is also possible to cold press the iron powder to obtain a compact, which is used for steel making. These post-processing steps are The general steps in the art. In a preferred embodiment of the third aspect of the present application, the iron ore mixture is composed of iron ore, anthracite, and lime.

With the method of the third aspect of the present application, iron ore, particularly nickel red iron ore, mirror iron or titanium magnetite, can be effectively reduced to iron under non-blast furnace iron making conditions. The iron powder obtained by the method of the third aspect of the invention can achieve a total iron content of greater than or equal to 90% by weight, and the recovery of iron is also greater than or equal to 90%. In particular, for nickel laterite ore, the recovery of Ni is ≥75%; for titanomagnetite, the reduced iron powder obtained has a total iron content of 90% by weight or more, Ή02 content ≤1%, and the recovery rate of Fe More than 92%. The various technical solutions of the present application can also obtain the following advantages:

1. Can make full use of iron ore sources that have not been valued by people, such as low-nickel laterite iron ore, titanomagnetite and mirror iron ore. At the same time, because this part of the resources is not valued by people, the resource cost is low and the sources of iron, nickel and titanium resources can be expanded.

2. Eliminate the need for coking, pelleting and sintering processes and reduce the investment in large fixed assets.

3. No coking coal and coke, only general coal, and no competition for blast furnace coal with scarce resources. Generally, the coal resources are abundant and the price is low, and there is no worries.

4. Simple process, short process, low investment, energy saving and emission reduction.

5. Realize the industrial production of low-nickel laterite iron ore, in line with national industrial policies, and achieve a nickel recovery rate of greater than or equal to 75%.

6. Before the solution, the steel industry has been unable to use the iron ore ironmaking problem alone and expand the iron ore resources of ironmaking.

7. Solved the problem of effective development and utilization of low grade refractory titanium magnetite. The invention will now be further described by reference to specific examples. However, the invention is not limited by these specific examples.

Example

The raw materials used in the following examples are as follows:

Anthracite powder: from Yongxing County, Hunan, China. Lime powder: from Wuchuan County, Guilin, Guangxi, China

Nickel red clay powder: from Indonesia.

Mirror iron ore powder: from Indonesia

Titanium magnet powder: from Indonesia. Example 1 -5 Preparation of Iron Ore Mixture 1 -5

At normal temperature and normal pressure, in a conventional mixing apparatus, iron ore fines, non-bituminous coal and lime are uniformly mixed as shown in Table 1, to obtain an iron ore mixture 1 - 5.

Table 1 Iron ore mixture 1 - 5

Solid iron ore powder amorphous carbon calcium oxide

Shi

Species and specifications for use in various types of specifications , class , class , class , kg kg kg

1 Nickel TFe=40.15%, 10 none C% =73.11%, ash 1.7 stone CaO% =81.16%, 2.2 red Ni%=1.24%, grain smoke %=1155%, ash particle size 200 mesh

Soil size is finer than 1mm coal particle size 200 mesh

Iron

Mine

2 Nickel TFe=48.33%, 10 none C% =73.11%, ash 1.82 stone CaO% =80.55%, 2.46 red Ni%=0.86%, grain smoke fraction =20.21%, grain ash particle size 200 mesh

Soil is finer than 1mm coal, 200 mesh

Iron

Mine

3 Mirror TFe=64.5%, S 10 no C%=73.20%, ash 1.86 stone CaO%=81.20%, 0.6 iron% <0.2%, P% smoke%=16.81%, ash size finer than 140 mesh mine<0.2 %, particle size fine coal S%=0.58%, particle size

At 1mm finer than 48 mesh

4 Mirror TFe=56.78%, S 10 no C%=75.61%, ash 1.4 stone CaO%=81.20%, 0.86 iron%<0.2%, P%%%=20.12%, ash size finer than 140 mesh<0.2 %, particle size fine coal S%=0.61%, particle size

At 1mm finer than 48 mesh

5 Titanium TFe=43.60%, 27 No C%=73.41%, ash 4 stone CaO%=81.20%, 3 magnetic smoke fraction=6.24%, S % ash Si0 ₂ content

Ti0 ₂ content Iron = 9.08%, Si0 ₂ coal = 0.53%, fine particle size = 0.57%, MgO ore in 140 mesh = 1.03%, particle size

Content = 6.62%,

Finer than 140 mesh

A1 ₂ 0 ₃ content

=4.49 % , CaO

Content = 1.09%,

MgO content

=2.15%, fine granularity

At 1

Note: TFe: total iron content, based on ore weight

C%: fixed carbon content, based on the weight of ore or anthracite

Ash content: ash content, based on the weight of anthracite

The remaining weight percentages are based on the weight of the corresponding materials (iron ore, anthracite, lime). Examples 6 - 10 Reduction and obtaining iron powder

The iron ore mixture 1 - 5 obtained above was placed in a silicon carbide reduction tank, and the tank was placed in a tunnel kiln, and preheated in a tunnel kiln using liquefied gas as a fuel under the conditions shown in Table 2 below. The reduction reaction controls the amount of air so that the combustion flame in the tunnel kiln is orange, thereby ensuring that the reaction step is carried out under a reducing atmosphere. After the predetermined reaction time, the product was cooled and pulverized to a particle size of less than 0.3 mm, and then the iron powder was magnetically selected. The total iron content, yield and other impurity information of the obtained iron powder are also given in Table 2. During the preheating process, all examples were heated from ambient temperature to 1100 °C for the time indicated in Table 2. The entire preheating and reduction process is carried out at atmospheric pressure.

Table 2

Example iron ore preheating reduction iron powder

Mixture time , temperature , c time , min iron content , other iron yield , %

Min weight%

6 1 240 1270 90 90.78 Nickel content is 92.31

2.03 wt%,

Nickel recovery

For 76.32 weight

% 2 1250 100 91.34

210 nickel content 1.438

90.26% by weight, nickel

The recovery rate is

75.02 weight %

3 240 1200 90 92.36 96.02

4 1220 90 93.12

240 94.77

5 240 1250 100 90.43 Titanium dioxide containing 91.49

The amount is 0.92

the amount%

Note: All weight % above is based on the weight of iron powder

Iron yield = amount of iron finally obtained / iron content of iron ore powder X 100%

Recovery of nickel = amount of nickel finally obtained / nickel content of nickel laterite ore X 100% As can be seen from Table 2, the present application can fully utilize three previously unusable iron ore and obtain more than 90%. Iron yield.

Claims

Rights request

An iron ore reducing agent comprising 8-35 parts by weight of amorphous carbon and 4 to 35 parts by weight of calcium oxide.

2. The iron ore reducing agent according to claim 1, wherein the amorphous carbon is 8 to 29 parts by weight and the calcium oxide is 14 to 29 parts by weight; preferably, the amorphous carbon is 10 to 15 parts by weight, and the calcium oxide is 15 to 22 Parts by weight.

3. The iron ore reducing agent according to claim 1, wherein the amorphous carbon is 8 to 29 parts by weight and the calcium oxide is 4 to 29 parts by weight; preferably, the amorphous carbon is 8 to 15 parts by weight, and the calcium oxide is 4 to 9 Parts by weight.

The iron ore reducing agent according to claim 1, wherein the amorphous carbon is 13 - 34 parts by weight and the calcium oxide is 9 - 31 parts by weight; preferably the amorphous carbon is 13 - 17 parts by weight, and the calcium oxide is 9 - 13 Parts by weight.

The iron ore reducing agent according to any one of claims 1 to 4, wherein the amorphous carbon is supplied in the form of anthracite, the fixed carbon content of the anthracite is 70% by weight, preferably the fixed carbon content of the anthracite

>75% by weight, based on the weight of anthracite.

7. The iron ore reducing agent according to any one of claims 1 to 6, wherein the amorphous carbon has a particle size of 48 mesh or finer, preferably 200 mesh or finer; and the calcium oxide has a particle size of 150 mesh or finer, preferably 200 mesh. Or finer.

The iron ore reducing agent according to any one of claims 1 to 7, wherein the iron ore is selected from the group consisting of nickel red iron ore, mirror iron or ore magnetite.

9. The iron ore reducing agent of claim 8 wherein said nickel red iron ore has a nickel content of less than 1.7% by weight and a total iron content of > 35 weight percent based on the weight of the nickel red iron ore; wherein said mirror The total iron content of the iron ore is > 35 wt%, based on the weight of the specular iron ore; wherein the titanomagnetite has a titanium dioxide content of 8-15% by weight, and the total iron content is > 35 wt%, based on the titanium magnet The weight of the mine.

The iron ore reducing agent according to any one of claims 1 to 9, wherein the iron ore reducing agent is composed of anthracite and lime.

12. The iron ore mixture of claim 11 wherein the iron ore is 100 parts by weight; the amorphous carbon is 8 - 29 parts by weight and the calcium oxide is 14 - 29 parts by weight; preferably the amorphous carbon is 10 - 15 parts by weight, And the calcium oxide is 15-22 parts by weight.

13. The iron ore mixture of claim 11 wherein the iron ore is 100 parts by weight; the amorphous carbon is 8 to 29 parts by weight and the calcium oxide is 4 to 29 parts by weight; preferably the amorphous carbon is 8 to 15 parts by weight. And the calcium oxide is 4-9 parts by weight.

14. The iron ore mixture of claim 11 wherein the iron ore is 100 parts by weight; the amorphous carbon is 13 - 34 parts by weight and the calcium oxide is 9 - 31 parts by weight; preferably the amorphous carbon is 13 - 17 parts by weight, And the calcium oxide is 9-13 parts by weight.

16. The iron ore mixture according to any one of claims 11 to 15, wherein the calcium oxide is provided in the form of lime, the lime having a calcium oxide content of >75% by weight, preferably having a calcium oxide content of >80% by weight, based on lime the weight of.

The iron ore mixture according to any one of claims 11 to 16, wherein the iron ore has a particle size of 1 mm or less; the amorphous carbon has a particle size of 48 mesh or finer, preferably 200 mesh or finer; The particle size is 150 mesh or finer, preferably 200 mesh or finer.

18. The iron ore mixture of any of claims 11-17, wherein the iron ore is selected from the group consisting of nickel iron ore, mirror iron or ore magnetite.

19. The iron ore mixture of claim 18, wherein said nickel red iron ore has a nickel content of less than 1.7 wt%, and a total iron content of > 35 wt%, based on the weight of the nickel red iron ore; wherein said mirror iron The total iron content of the ore is >35 wt%, based on the weight of the specular iron ore; wherein the titanomagnetite has a titanium dioxide content of 8-15 wt%, and the total iron content is > 35 wt%, based on titanomagnetite the weight of.

The iron ore mixture according to any one of claims 11 to 19, wherein the iron ore mixture is composed of iron ore, anthracite and lime.

21. A method of reducing iron ore comprising the steps of:

Mixing step: mixing 100 parts by weight of iron ore, 8-35 parts by weight of amorphous carbon and 4 - 35 parts by weight of calcium oxide to obtain an iron ore mixture;

22. The method of claim 21, wherein the temperature of the reacting step is from 1180 to 1300 °C, preferably from 1200 to 1300 °C.

23. Process according to claim 21 or 22, wherein the reaction step is carried out for 30 to 120 minutes, preferably 80 to 110 minutes.

The method according to any one of claims 21 to 24, wherein the iron ore is 100 parts by weight; the amorphous carbon is 8 to 29 parts by weight and the calcium oxide is 14 to 29 parts by weight; preferably the amorphous carbon is 10 - 15 parts by weight. Parts, and calcium oxide is 15-22 parts by weight.

The method according to any one of claims 21 to 24, wherein the iron ore is 100 parts by weight; the amorphous carbon is 8 to 29 parts by weight and the calcium oxide is 4 to 29 parts by weight; preferably the amorphous carbon is 8 to 15 parts by weight. And calcium oxide is 4-9 parts by weight.

The method according to any one of claims 21 to 24, wherein the amorphous carbon is provided in the form of anthracite, the fixed carbon content of the anthracite is 70% by weight, preferably the fixed carbon content of the anthracite, 75 wt%, based on the weight of the anthracite .

The method according to any one of claims 21 to 28, wherein the calcium oxide is provided in the form of lime, the calcium oxide content of the lime is 75 wt%, preferably the calcium oxide content of lime is 80 wt%, based on the weight of the lime.

30. The method of any of claims 21-29, wherein the iron ore has a particle size of 1 mm or less; the amorphous carbon has a particle size of 48 mesh or finer, preferably 200 mesh or finer; and the calcium oxide has a particle size of 150 The order is finer or finer, preferably 200 mesh or finer.

The method of any one of claims 21 to 30, wherein the iron ore is selected from the group consisting of nickel-ironite, mirror iron or tetra-magnetite.

32. The method of claim 31, wherein said nickel red iron ore has a nickel content of less than 1.7% by weight, and a total iron content of > 35 weight percent, based on the weight of the nickel red iron ore; wherein said total of specular iron ore The iron content is >35 wt%, based on the weight of the specular iron ore; wherein the titanium magnetite contains titanium dioxide The amount is 8 - 15% by weight, and the total iron content is > 35% by weight, based on the weight of the titanomagnetite.

33. The method according to any one of claims 21 to 32, wherein the method further comprises preheating the mixture at a temperature of 200 to 1100 ° C for 2 to 5 hours between the mixing step and the reaction step (please ask for preheating) ^ ί'矣, stress.

34. The method of any of claims 21 to 33, wherein the reacting step is carried out in an apparatus selected from the group consisting of a rotary hearth furnace, a rotary kiln, a tunnel kiln, and a raceway kiln.

35. The method of any of claims 21-34, wherein the iron ore mixture is comprised of iron ore, anthracite, and lime.

36. The method of any of claims 21 to 35, wherein the reacting step is performed at ambient pressure.