JPH0226829A - Production of synthetic rutile - Google Patents

Abstract

PURPOSE:To economically obtain synthetic rutile with eliminating a pre-treatment furnace and other equipment by treating the gas produced from a selective chlorination furnace in the production of synthetic rutile by introducing to a condensing system in the producing process of TiCl4. CONSTITUTION:The low grade ore contg. Ti such as ilmenite is charged to the selective chlorination furnace, and then, mainly iron component, etc., are chlorinated and removed by volatilizing to produce synthetic rutile. The gas produced from the furnace is sent not to an exclusively treating system but to the condensing system in the producing equipment of TiCl4, and thereafter treated in the producing process of TiCl4. That is, the produced gas sent to the condensing system is separated in earnest into CO2, TiCl4 and produced chlorinated substance in this process. The produced chlorinated substance is introduced to a chlorine-recovering system together with the chlorinated substance produced in the producing equipment of TiCl4, if condensed before the condensing system, together with the condensed chlorinated substance. Then, the recovered chlorine is introduced to a chlorine-purifying system, preceding process in the producing equipment of TiCl4, to obtain high grade chlorine, and the waste from the chlorine-recovering system is treated with a waste water disposal plant in the producing equipment above-mentioned in the same way.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention is a method of selective chlorination in the process of producing synthetic rutile by selectively chlorinating the iron components of low-grade titanium-containing ores such as ilmenite and removing them by volatilization. The present invention relates to a method for producing synthetic rutile that simplifies synthetic rutile production equipment and lowers operating costs by streamlining the treatment of gas generated from a furnace.

The above-mentioned low-grade titanium-containing ore is mainly composed of iron, except for 74%, but also contains Mn, Al, Mg, etc. In this specification, all components except 74 minutes are expressed as iron components.

[Conventional technology]

The most common conventional synthetic rutile manufacturing process is shown in flowcharts in FIGS. 2 and 3.

After preliminary treatment, ores with a titanium content of 60% or less, such as ilmenite, are mixed with coke, inserted into a fluidized bed chlorination furnace, and heated to around 1000°C to selectively remove iron components from the ore. Chlorinate.

The raw material in the furnace from which iron components have been removed is extracted from the selective chlorination furnace, the coke is removed by sieving, the unreacted ore is removed by magnetic separation, etc., and the reacted part is calcined to obtain synthetic rutile with a grade of 90% or higher. It will be done.

On the other hand, chlorine is recovered from the gas produced in the chlorination furnace in the steps shown in the flowchart. Carbon dioxide gas neutralizes chlorine bones and is exhausted. FIG. 2 is a flowchart for recovering chlorine in a gaseous state from produced gas, and FIG. 2 is a flowchart for recovering produced chloride in solid form and then recovering chlorine.

[Problems to be Solved by the Invention] As is clear from the flowchart, the above-mentioned conventional method for producing synthetic rutile consists of one independent step, and in this method, it is necessary to selectively chlorinate only the iron component, etc. If T i O□ is chlorinated, it becomes a loss. Therefore, a pretreatment process has been required to enhance the selective chlorination of iron components and the like. For example, JP-A No. 62-191425 discloses a preliminary treatment in which titanium-containing ore is heated in a reducing atmosphere of hydrocarbon gas, and JP-A No. 49-123918 discloses a pretreatment process in which ore is heated below the sintering temperature in an oxygen-containing atmosphere. A heat activation pretreatment step is disclosed.

In addition, when chlorinating in a selective chlorination furnace, the temperature is 1°00°C.
When the temperature exceeds Tie, the temperature also becomes chlorinated, 950
If the temperature drops below .degree. C., the reaction rate slows down and the yield deteriorates, so strict operations are required.

Furthermore, in the process of recovering chlorine from the gas produced from the selective chlorination furnace, the method of directly introducing oxygen and causing oxidative roasting to recover chlorine requires liquefaction distillation and carbon dioxide gas separation equipment, which requires considerable equipment costs. Bulk.

Additionally, the selective chlorination method essentially requires equipment to neutralize the chlorine content, such as removing chlorine bones from carbon dioxide gas and neutralizing discharged chloride. If such facilities were to be constructed for the rutile production process, it must be said that the production of synthetic rutile would not be economically viable other than maintaining a large production volume.

In view of the above problems, an object of the present invention is to simplify the production equipment in the selective chlorination method, to provide a method for producing synthetic rutile that can be produced economically even in a relatively small amount, and that is easy to operate. be.

[Means to solve the problem]

In order to achieve the above object, the present inventors decided to introduce the gas generated in the selective chlorination furnace into the condensation system of the titanium tetrachloride production facility in the process of producing synthetic rutile. Before introducing this condensation system, titanium tetrachloride among the chlorides generated in the selective chlorination furnace is condensed. Components having a boiling point higher than 1 temperature may be condensed and collected, and the remaining component gas may be introduced to the condensation system of the titanium tetrachloride production facility.

That is, the invention of claim 1 provides, for example, ilmenite, etc.
In the process of producing synthetic rutile by chlorinating and volatilizing the iron components of low-grade titanium-containing ores, the generated gas from the selective chlorination furnace is introduced into the condensation system of the titanium tetrachloride production process. The gist of the invention is a method for producing synthetic rutile to be treated, and the invention of claim 2 condenses and collects a chloride gas component having a boiling point higher than that of titanium tetrachloride in the generated gas from the selective chlorination furnace, and removes the remainder of the generated gas. Similarly, the gist is a method for producing synthetic rutile, which is introduced into the condensed system of the titanium tetrachloride production process and treated in the same process.

[For production] The above method yielded the following very important advantages.

That is, when the titanium-containing ore is first charged into the selective chlorination furnace, the ore does not require any preliminary treatment. If you insist, preheating alone is sufficient. This is because some chlorination of T i O is allowed. This is because the produced titanium tetrachloride is liquefied and collected in the condensation system of the titanium tetrachloride manufacturing process, and is effectively used for manufacturing titanium metal or chlorinated titanium oxide. This eliminates the need for a conventional pretreatment furnace.

Also, for the above reasons, the strict operation of selective chlorination in a chlorination furnace has become somewhat easier. Furthermore, any method can be used to recover chlorine from the gas produced by the selective chlorination furnace, and special equipment for neutralizing chlorine in waste is no longer required.

(Example〕 FIG. 1 shows a flow chart of the steps of the method of the present invention.

The upper part of the chart is the general titanium tetrachloride production process, and the lower part is the synthetic rutile production process, and the two are organically linked.

In the diagram, (1) and (2) indicate that gas components with a higher boiling point than titanium tetrachloride are condensed and collected before the gas generated in the selective chlorination furnace is led to the a-condensation system of the titanium tetrachloride manufacturing process. Case (2
), and when the gas is instead led to the condensate system (1
) is shown.

In the method of the present invention, as shown in the flowchart of FIG. 1, titanium ore such as ilmenite can be charged into a selective chlorination furnace without the need for pretreatment.

After that, the raw material in the furnace from which iron components have been removed through chlorination is drawn out of the furnace, and coke and unreacted ilmenite are removed.The process for producing synthetic rutile is different from the synthetic rutile production method in -C. do not have.

However, in the method of the present invention, the gas produced in the selective chlorination furnace is not sent to a dedicated treatment system, but is led to the condensation system of the titanium chloride manufacturing facility, and is then treated in the titanium tetrachloride manufacturing process.

In this condensation system, titanium tetrachloride and other chlorides are condensed and separated by a well-known titanium tetrachloride manufacturing process.

In the method of the present invention, titanium tetrachloride is produced in a selective chlorination furnace using spraying or other cooling methods to a temperature higher than the condensation temperature of titanium tetrachloride before entering the condensation system of the titanium tetrachloride manufacturing process. It is acceptable to condense and collect some of the chloride.

The produced gas that enters the condensed system is fully converted to carbon dioxide,
Titanium tetrachloride is separated from the produced chloride.

The carbon dioxide gas is disposed of after neutralizing the chlorine content in the exhaust gas treatment system following the condensation system.

Titanium tetrachloride is recovered together with that produced in titanium tetrachloride production equipment and is effectively used in the production of titanium metal.

The produced chloride is led to the chlorine recovery system together with the chloride produced in the titanium tetrachloride production facility, and further together with the chloride if condensed before entering the condensation system.

In the chlorine recovery system, any method may be used, including the conventionally well-known method of generating chlorine by roasting with oxygen.

In addition, recovered chlorine can be treated and reused in any way, but if it is sent to the chlorine purification system, which is the pre-process of titanium tetrachloride manufacturing equipment, high-quality chlorine can be produced without the need for complex treatment equipment. is obtained.

Waste from the chlorine recovery system is similarly treated in the wastewater treatment facility of the titanium tetrachloride production facility.

An example will be described.

Australian ilmenite (TiOz 53%, Fe025.2%, Fe
tus 16.3%) and calcine coke (containing 16.3%
15% by weight of ilmenite) mixed with 650
It was filled to a height of mm. Then, the temperature was raised to 1000°C while flowing with Ar.

Next, replace Ar with 1.2ONrrf/Hr of chlorine,
At the same time, a heated mixture of 85 kg/H of ilmenite and 5.3 kg/H of calcine coke was continuously added to the fluidized bed.

The iron content in ilmenite was chlorinated and led from the chlorination furnace to the next cooling device. There, the gas produced from the chlorination furnace was cooled down to 150"C by spray evaporation of titanium tetrachloride. This made it possible to separate titanium tetrachloride or compounds with lower boiling points from other compounds. Titanium tetrachloride and compounds with lower boiling points were led to the titanium tetrachloride condensation collection system in the titanium tetrachloride manufacturing process via a pressure regulating valve.

Compounds with high boiling points are transferred to a chlorine recovery process using a known oxidation roasting method, and chlorine is recovered with a recovery rate of approximately 90%.
It was sent to the chlorine purification equipment in the pre-production process of titanium tetrachloride and used again for chlorination.

On the other hand, the raw material in the furnace was removed from the selective chlorination furnace at a rate of about 60 kg/H, and most of the coke was removed through a 32-mesh sieve. The unreacted ilmenite was then returned to the chlorination furnace to be reacted again by magnetic beneficiation. The screened coke was also returned to the chlorination furnace.

The reacted portion contained 89% T i O and coke. Therefore, this was fired to obtain synthetic rutile with a grade of 92.2%.

〔Effect of the invention〕

In the present invention, in the production of synthetic rutile, the generated gas from the selective chlorination furnace is processed in the titanium tetrachloride production process, so a pretreatment furnace and other dedicated processing equipment in front of the selective chlorination furnace are required. This process can be omitted and has the remarkable effect of economically producing synthetic rutile with simple equipment.

[Brief explanation of the drawing]

Figure 1 is a flowchart of the present invention, in which (1) shows the case where the gas generated in the selective chlorination furnace is directly led to the condensation system of the titanium tetrachloride production process, and (2) shows the case where the gas generated in the selective chlorination furnace The case is shown in which the material is partially cooled, condensed and collected before being introduced into the condensation system of the titanium tetrachloride manufacturing process. Figures 2 and 3 are general flowcharts for the production of synthetic rutile, with Figure 2 recovering chlorine in a gaseous state from the chloride produced, and Figure 3 recovering the chloride produced in solid form and then recovering the chlorine. It is something to be collected.

Claims (1)

[Claims] 1. Chlorinating mainly iron components of low-grade titanium-containing ore,
A method for producing synthetic rutile, which comprises introducing the generated gas from a selective chlorination furnace into a condensation system of a titanium tetrachloride production process and treating it in the same process, in the process of producing synthetic rutile by volatilization removal. 2. Chlorinate mainly iron components of low-grade titanium-containing ores,
In the process of producing synthetic rutile by volatilization removal, the produced gas from the selective chlorination furnace is condensed and collected to collect the chloride gas component whose boiling point is higher than that of titanium tetrachloride, and the remainder of the produced gas is used in the titanium tetrachloride production process. A method for producing synthetic rutile characterized by introducing it into a condensed system and treating it in the same process.