CN1239120A

CN1239120A - Process for producing high-content gulf red with magnetite ore

Info

Publication number: CN1239120A
Application number: CN 98102256
Authority: CN
Inventors: 张东旭; 张�浩
Original assignee: Individual
Current assignee: Individual
Priority date: 1998-06-11
Filing date: 1998-06-11
Publication date: 1999-12-22

Abstract

A process for producing high-content gulf red with magnetite ore as raw material includes dressing ordinary magnetite ore powder, purifying to make TFe more than 71.5% and SiO2 less than 0.3%, calcining at 50-1000 deg.C to obtain gulf red with Fe2O3 content more than 98%, and ball grinding. It features very low conten of impurities, and can be used as high-grade magnetic material in food, medicine and military products.

Description

Method for producing high-content iron oxide red by using magnetite ore

The invention relates to a method for producing Fe₂O₃In particular for producing high Fe contents from magnetite₂O₃The method of (1).

Fe₂O₃Also called iron oxide red, is an important raw material in industry, and one of the current methods for producing iron oxide red is to produce iron oxide red from industrial waste materials such as scrap steel sheet or iron scale by a wet process, and the basic reaction equation is as follows:

fe obtained by the above reaction formula₃O₄Then obtaining Fe through process heat treatment₂O₃The iron oxide red produced by the method has complex chemical components in the raw materials, directly influences the product quality and cannot reach high content of Fe₂O₃It is difficult to adapt to high-tech electronicsThe product and the military product. Another method is a method for producing synthetic iron oxide red pigment from magnetite ore (CN1082513A), which discloses the preparation of iron oxide red Fe from magnetite ore₂O₃The method comprises the steps of stirring and reacting ore powder with sulfuric acid with insufficient reaction amount, drying, crushing, calcining, cooling and crushing the material to obtain the raw material iron oxide red of the pigment. The first method is a method in which raw materials are derived from industrial waste and thus are not easily supplied, and the second method is a method in which pigments are produced, and the above-mentioned two methods cannot ensure that the raw materials contain Fe due to the complicated chemical composition₂O₃The amount of the additive reaches more than 98 percent, and the additive is difficult to adapt to the requirements of electronic military products in China. And the two processes have great environmental pollution. With the development of the electronic industry, the high-content ferric oxide (the content is more than 98%) in electronic products has wider and wider application, and most of the products used in China are imported at present.

The inventionaims to provide a method for producing high-content Fe by using magnetite ore₂O₃The method is simple, can be mass-produced, has no pollution to environment, and Fe in the product₂O₃The content can reach more than 98 percent.

The invention is realized according to the following technical scheme. The method comprises the following procedures:

(1) and (4) mineral separation. Crushing and grinding magnetite quartzite with TFe (total iron) content of about 30%,

Magnetic separation to reach TFe content of 65-68%, crushing, grinding, and magnetic separation to reach TFe content

The content is more than or equal to 71.5 percent, and SiO is₂Ore powder less than or equal to 0.3 percent. The above-mentioned work can be implemented by using crusher, ball mill,

Magnetic separator.

(2) And (4) roasting. The TFe content is not less than 71.5 percent and SiO₂The ore powder with the content less than or equal to 0.3 percent is 50 to

Roasting at 200 deg.C to 1000 deg.C while continuously turning over, and introducing air or oxygen

And then cooling.

(3) And (4) grinding. The ore powder is partially agglomerated during roasting, and is ground and ball-milled

And (5) finishing. And then packaging according to the use requirements in grades.

Due to high purity of Fe₂O₃Not uncommon in nature, it is always associated with other elements, in particular with SiO₂The magnetic quartzite is formed by mixing the magnetic quartzite and the magnetite, and the quartzite ore has low price and can be purchased in large quantity as a raw material. In the process of ore dressing, the TFe content is equal to or more than 71.5 percent, and SiO is selected₂The content is less than or equal to 0.3 percent, which is the most economical. When the ore powder separated by the procedures of crushing, grinding and magnetic separation can not reach the content, the ore can be circulated again by the ore dressing to achieve the purpose. The calcination temperature is preferably from 50 ℃ to 200 ℃, the temperature is uniformly raised to 1000 ℃, and the temperature is preferably cooled to 50 ℃, so that TFe is sufficiently converted into Fe₂O₃Particularly, the temperature between 910 ℃ and 1000 ℃ is the key temperature for conversion, the conversion of ore particles is slower when the temperature is lower than 910 ℃, the conversion is not complete enough, and the ore powder is easy to overheat when the temperature is higher than 1000 ℃, and the quality is poor. TFe being total iron, i.e. Fe₃O₄The structure is that the substance in the mineral powder particles is FeO, and the exterior of the particles is coated with Fe₂O₃The layer surrounds the substrate and becomes Fe when in contact with oxygen due to the unstable chemical state of FeO₂O₃Form Fe₂O₃And (3) a layer. During the roasting process, the FeO in the TFe particles can be quickly and completely converted into Fe by continuously turning over and introducing oxygen₂O₃To increase Fe in the ore powder₂O₃The chemical reaction formula is as follows:

adopt sealed container to splendid attire ore powder, avoid influencing product quality because ore powder thermal expansion loss and sneak into impurity, be favorable to the transport in addition and the non-staining environment. The sealed container is provided with an oxygen supply or inflation device and isCan be made of CrNi alloy.

The following embodiments are specifically described.

In this embodiment, magnetite-quartzite ore is used as a raw material, and the ore dressing is performed first, that is, ore powder is prepared. Crushing ore containing about 30% of TFe with a crusher, further grinding with a ball mill, separating magnetite ore from impurities with a magnetic separator to make the TFe content reach 65-68%, and further purifying by the above process to obtain SiO with TFe content of 71.5 or more₂Not less than 0.3 percent of ore powder with about 200 meshes. The ore powder is roasted in a sealed container.

FIG. 1 is a schematic view showing the calcination in a muffle kiln, a tunnel kiln, or an electric kiln;

FIG. 2 is a schematic view of firing in a vertical kiln;

FIG. 3 shows a schematic view of firing in a rotary kiln.

Referring to fig. 1, a sealed container 1 containing about 1/2% ore powder is placed on a skip car 2, the skip car 2 is provided with a rotating mechanism (not shown) for rotating the container 1, the skip car 2 is driven by a chain 4, the container 1 is provided with an air inlet 3 for introducing air or oxygen, the container 1 is put into a kiln from 50 ℃, is heated to 1000 ℃ from a preheating zone a to a combustion zone B for 10 hours, and is taken out of the kiln from a cooling zone C for the same time.

Referring to fig. 2, a sealed container 1 containing about 1/2 volume of ore powder is positioned in a shaft kiln shell 2, the container 1 is driven to rotate by a top rotating system (not shown), oxygen or air is introduced from a top air inlet 3 to promote the conversion of the ore powder, the temperature in the kiln is 200 ℃, the temperature is raised to 1000 ℃ after 3 hours, and the container is naturally cooled to 50 ℃ so far. The process has high roasting speed and saves production time.

Referring to fig. 3, the sealed container 1, i.e. the rotary drum in the rotary drum kiln, is closed at one end and is wrapped at the other end by a cloth bag collector 5, mineral powder is loaded into a bin 2 by a lifter 4, blown into the rotary drum from an inlet at the end by a high-pressure blower 3, passes through a preheating zone a, a combustion zone B and a cooling zone C, and is collected by the cloth bag collector 5 from the other end.

And grinding the substances obtained by roasting in the above manner to the required granularity by using a ball mill, and packaging to obtain the finished product.

The method of the invention is used for preparing Fe with Chinese iron oxide red as the product name₂O₃The detection of metallurgical department shows that all indexes of the Fe alloy reach or are superior to international levels, and the Fe produced by the method of the invention is detected₂O₃The product contained the components (in weight%) as shown in table 1.

TABLE 1

Fe₂O₃ 98.5-99.95	C 0.01-0.016	Mn 0.03-0.036
Fe₂O₃ 98.5-99.95	C 0.01-0.016	Mn 0.03-0.036	P 0.01-0.06	S 0.002-0.004	Ni 0.0057-0.006
Cu 0.0016-0.0039	Co 0.0018-0.0025	Zn 0.0085-0.013	P 0.01-0.06	S 0.002-0.004	Ni 0.0057-0.006
Cu 0.0016-0.0039	Co 0.0018-0.0025	Zn 0.0085-0.013	Pb 0.0065-0.0085	SiO₂≤0.3

The product was compared with similar products in other countries internationally, as shown in table 2.

TABLE 2

As can be seen from Table 1, the product contains Fe₂O₃The content of the SiO reaches 98.5 to 99.9 percent₂Less than or equal to 0.3 percent and almost no harmful impurities. As can be seen from Table 2, the product has Fe₂O₃The content reaches 98.5-99.95%, which reaches the level of similar products of English, American and Germany internationally.

In conclusion, the invention adopts the magnetite-quartzore as the raw material, the raw material is easy to obtain and the price is low; obtaining ore powder with high TFe content by crushing, grinding and magnetic separation; the raw materials are pure, the ore powder is not required to be treated by nitric acid and sulfuric acid by a chemical method, and the environment is not polluted; the roasting is carried by adopting a sealed container, so that impurities are prevented from being mixed and ore powder is prevented from being lost; air is introduced during roasting to ensure that FeO can be completely and rapidly converted into Fe₂O₃(ii) a The method has simple and easy process, and is suitable for mass or flow line production: can reach high content of Fe₂O₃The iron oxide red is used for manufacturing high-grade magnetic materials to meet the requirements of high-technology products such as electronics, national defense industry and the like, and can also be applied to the pharmaceutical and food industry.

Claims

1. Production of high Fe content from magnetite ore₂O₃The method is characterized in that: it comprises the following procedures:

(1) mineral separation, namely crushing, grinding and magnetically separating the magnetite quartzite with the TFe content of about 30 percent to obtain the TFe content

The content is 65-68%, and then the mixture is crushed, ground and magnetically separated to ensure that the TFe content is more than or equal to 71.5%, and SiO is obtained₂Comprises

Ore powder with the amount less than or equal to 0.3 percent;

(2) roasting until the TFe content is more than or equal to 71.5 percent and SiO₂The ore powder with the content less than or equal to 0.3 percent starts from 50 ℃to 200 ℃,

uniformly heating to 1000 deg.C, continuously turning, introducing air or oxygen, and cooling;

(3) grinding, and grinding the cooled material to a desired particle size.

2. The method of claim 1 for producing high Fe content magnetite ore₂O₃The method is characterized in that: the ore powder is roasted in a sealed container, and oxygen or air is introduced into the container.

3. The method of claim 2 for producing high Fe content magnetite ore₂O₃The method is characterized in that: the sealed container is roasted in muffle kiln, electric kiln or tunnel kiln, and has oxygen or gas supplying unit inside it, which is rotated by a rotating mechanism and conveyed by a chain conveyer.

4. The method of claim 3 for producing high Fe content magnetite ore₂O₃The method is characterized in that: the roasting process is to heat the mixture from 50 deg.c to 1000 deg.c for 5 hr and to cool at the same cooling speed.

5. The method of claim 2 for producing high Fe content magnetite ore₂O₃The method is characterized in that: the sealed container is roasted in vertical kiln, rotated by rotating mechanism and supplied with oxygen or gas by oxygen supplying device.

6. The method of claim 5 for producing high Fe content magnetite ore₂O₃Method of (1), which is characterized inCharacterized in that: the roasting process is to heat the mixture from 200 deg.c to 1000 deg.c for 3 hr and to cool the mixture naturally to 50 deg.c.

7. The method of claim 2 for producing high Fe content magnetite ore₂O₃The method is characterized in that: the sealed container is a rotary cylinder of the rotary cylinder kiln, mineral powder is blown in from one end of the rotary cylinder by an air blower, the temperature is uniformly raised from 50 ℃ to 1000 ℃, and then the mineral powder is cooled, sent out from the other end of the rotary cylinder and collected by a cloth bag collector.