JP2008308738A - METHOD FOR MANUFACTURING METAL Ti OR Ti ALLOY - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing metal Ti or Ti alloy, by which Ca concentration in molten salt adhering to Ti grains or Ti-alloy grains formed in a reduction step can be decreased and the amount of Ca taken into a melting furnace can be consequently reduced. <P>SOLUTION: A mixture of the Ti grains or Ti-alloy grains formed in the reduction step and Ca-containing molten salt is cleaned with molten salt before melting to decrease Ca concentration in the Ca-containing molten salt and reduce the amount of Ca taken into the melting furnace. It is particularly desirable that a part of molten CaCl<SB>2</SB>from which Ca is removed by a Ca removal and concentration apparatus 5 attached to manufacturing equipment used for the execution of the method is stored in a molten CaCl<SB>2</SB>tank 15 for cleaning; and this molten CaCl<SB>2</SB>is used as the molten salt (e.g. molten CaCl<SB>2</SB>) for cleaning. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

The present invention relates to a metal Ti formed by Ca reduction, which includes a step of continuously dissolving Ti grains or Ti alloy grains formed by Ca reduction of TiCl ₄ and separated from a molten salt to form metal Ti or Ti alloy ingots. Alternatively, the present invention relates to a Ti alloy manufacturing method, and more particularly, to a metal Ti or Ti alloy manufacturing method capable of reducing the amount of Ca brought into the melting furnace.

As an industrial method for producing metal Ti, a crawl method in which TiCl ₄ is reduced with Mg is generally used. However, since this method is a batch type, there is a problem that the product price becomes very high. On the other hand, a technique for producing Ti by reducing TiCl ₄ with Ca has been proposed.

The present inventors consider that it is necessary to economically replenish Ca in the molten salt consumed in the reduction reaction in order to industrially establish the production method of metallic Ti by this Ca reduction. _{In addition} to utilizing the Ca generated by electrolysis of No. 2, a method of circulating this Ca, that is, the “OYIK method (Oic method)” was proposed.

This method, for example, as described in Patent Document 1, a step of separating the Ti particles Ca is reacted with TiCl ₄ to Ca in the molten CaCl ₂ was dissolved to produce a Ti grains reduction step and generates includes electrolytic process to increase the Ca concentration in the molten CaCl ₂ by the Ca concentration electrolytic molten CaCl ₂ was decreased with the generation of the Ti particles, the reduction of TiCl ₄ with Ca generated in the electrolytic process in the reduction step It is a manufacturing method of metal Ti to be used, and can be operated continuously by circulating and using Ca generated in the electrolysis step as a reducing agent.

Furthermore, in the method for producing metal Ti by this Ca reduction, the present inventors have conducted electrolysis that is long in one direction to hold a molten salt (for example, molten CaCl ₂ ) in an electrolysis step as described in Patent Document 2. It has a tank container, an anode and a cathode arranged along the longitudinal direction of the electrolytic cell container, and is provided with a molten salt supply port at one end in the longitudinal direction of the electrolytic cell container and melted at the other end. A method for producing metal Ti using an electrolytic cell provided with a molten salt outlet for extracting molten salt with increased Ca concentration generated by electrolysis of salt out of the electrolytic cell was proposed. According to this method, since Ca produced by continuously electrolyzing a large amount of molten salt can be supplied to the reduction step, it is possible to efficiently produce metal Ti.

In this method of producing metal Ti by reduction of Ca, Ti particles generated by reduction of TiCl ₄ are separated from molten CaCl ₂ and then transferred to a melting step where they are heated and dissolved to form a Ti ingot.

However, the molten CaCl ₂ is not completely removed in the separation step, and molten CaCl ₂ is adhered to the separated Ti particles, and the adhered molten CaCl ₂ contains a trace amount of Ca. Yes. Therefore, trouble caused by this Ca is likely to occur in the melting step, which hinders continuous operation. That is, since Ca is volatile and is likely to be gaseous, when the mixture of Ti grains and molten CaCl ₂ containing a small amount of Ca is simultaneously dissolved at the entrance of the melting step, Ca evaporates and the melting furnace There are also cases where it adheres to the inner surface of an inner wall or an exhaust pipe or the like, resulting in blockage of the pipe. In addition, Ca is an active metal and becomes fine particles after evaporation, so there is a risk of oxidizing and burning depending on the atmospheric conditions.

Therefore, in order to continuously produce metal Ti by Ca reduction over a long period of time, it is necessary to put Ti particles in which the Ca concentration of adhering molten CaCl ₂ is lowered to an extent that does not hinder the operation, into the melting furnace. become.

JP 2005-133195 A JP 2007-63585 A

  The present invention has been made in view of such circumstances, and its purpose is to produce Ti particles produced in the reduction step when manufacturing Ti or Ti alloy by a manufacturing process based on the OYIK method proposed by the present inventors. Or the manufacturing method of metal Ti or Ti alloy which can reduce the Ca density | concentration of molten salt adhering to Ti alloy grain, and can reduce the amount of Ca brought into a melting furnace to such an extent that it does not interfere with a continuous operation. About.

  In order to achieve the above-mentioned object, the present inventors have made extensive efforts to develop a technique that can be carried out relatively easily, particularly focusing on economic efficiency.

In order to reduce the amount of Ca brought into the melting furnace accompanying the Ti grains or Ti alloy grains, the Ti grains or Ti alloy grains to which the Ca-containing molten salt is adhered are dissolved to form a liquid phase, and the upper layer molten salt A method such as dissolution separation for removing (for example, molten CaCl ₂ ) is effective. However, this requires a large amount of energy, and an increase in manufacturing cost is inevitable. Further, by removing the CaCl ₂ any prolonged washing is considered a method of removing Ca contained in CaCl ₂ simultaneously, the production efficiency is significantly reduced, manufacturing cost is increased.

Therefore, the present inventors tried a method of washing a mixture of Ti grains or Ti alloy grains and Ca-containing molten salt (molten CaCl ₂ ) with another molten CaCl ₂ before charging the melting furnace. By washing, the so molten CaCl ₂ containing Ca in the mixture is replaced by other melt CaCl _2, using a low melt CaCl ₂ than Ca concentration in the molten CaCl ₂ in Ca concentration the mixture washed In this case, the molten CaCl ₂ in the mixture is replaced by the molten CaCl ₂ used for cleaning with the Ca dissolved therein, and the total amount of Ca contained in the mixture is reduced.

As the molten CaCl ₂ used for cleaning, for example, one having a low Ca concentration among molten CaCl ₂ circulated between the steps in the production process can be used, which is economically advantageous.

  The present invention has been made based on such an idea, and the gist thereof lies in the following method for producing metal Ti or Ti alloy.

That is, a reduction step of continuously supplying a metal chloride containing TiCl ₄ into a molten salt containing CaCl ₂ and dissolving Ca to produce Ti grains or Ti alloy grains in the molten salt, and the produced Ti grains Alternatively, a separation step of separating the Ti alloy particles from the molten salt, a melting step of continuously dissolving the separated Ti particles or Ti alloy particles to form an ingot of metal Ti or Ti alloy, and Ti particles or Ti alloy particles A metal Ti that includes an electrolysis step of increasing the Ca concentration by electrolyzing a molten salt having a reduced Ca concentration along with the formation, and using the molten salt having an increased Ca concentration generated in the electrolysis step to reduce TiCl _{4 in} the reduction step. Alternatively, in the Ti alloy production method, the Ca concentration of the Ca-containing molten salt is obtained by washing the Ti particles produced in the reduction step or a mixture of the Ti alloy particles and the Ca-containing molten salt with the molten salt before melting. It is lowered, a method for producing a metallic Ti or a Ti alloy, characterized in that to reduce the amount of Ca to be introduced into the melting furnace.

The “molten salt containing CaCl ₂ ” refers to a molten salt containing only molten CaCl ₂ or KCl, CaF ₂ or the like added to molten CaCl ₂ to adjust the melting point, viscosity, etc.

“Metal chloride containing TiCl ₄ ” is a metal chloride containing TiCl ₄ as an essential chloride, and TiCl ₄ alone or TiCl ₄ and a metal that becomes an alloy component of Ti, such as V, Al, Cr, etc. And metal chlorides. Simultaneously with the reduction of TiCl _4, the metal chloride as the Ti alloy component is also reduced by Ca. By using a metal chloride containing TiCl ₄ , it is possible to obtain a Ti alloy in addition to metal Ti. .

  The “mixture of Ti grains or Ti alloy grains produced in the reduction process and Ca-containing molten salt” is a mixture extracted from the reduction tank, and reacts with Ti grains or Ti alloy grains produced in the reduction process. It is a mixture with a Ca-containing molten salt in which residual Ca that is not used is dissolved. Since the Ti grains or Ti alloy grains and the Ca-containing molten salt are simultaneously extracted from the reduction tank as a mixture, the expression “generated in the reduction process” is also used for the Ca-containing molten salt. In addition, separation of Ti grains or Ti alloy grains and Ca-containing molten salt proceeds, for example, in a state where the Ca-containing molten salt is adhered after most of the Ca-containing molten salt is removed in the final stage of the separation process. Ti grains or Ti alloy grains are also a mixture of Ti grains or Ti alloy grains and a Ca-containing molten salt.

  The “molten salt” used for washing mainly refers to a molten salt that is circulated between each step in the manufacturing process, but also includes a newly prepared molten salt for the purpose of supplementing the manufacturing process with a bath salt. Since the “molten salt” is used to reduce the Ca concentration by washing a mixture of Ti grains or Ti alloy grains and a Ca-containing molten salt, the Ca concentration substantially includes the Ca content generated in the reduction step. It means a molten salt lower than the molten salt.

  In the method for producing metal Ti or Ti alloy according to the present invention, as an embodiment of the present invention, a molten salt having a lower Ca concentration than the Ca-containing molten salt produced in the reduction step is used as a molten salt for cleaning. However, the conditions regarding the Ca concentration that is substantially determined are specifically shown.

In the method for producing metal Ti or Ti alloy according to the present invention, the molten salt-side electrode plate in the Ca removal region that holds the molten salt separated in the separation step further includes a Ca concentration region separated from this region. By applying a voltage lower than the decomposition voltage of CaCl ₂ so as to be a positive electrode with respect to the electrode plate on the molten salt side of the molten salt, the molten salt in the Ca removal region where the concentration of Ca is lowered is sent to the electrolysis process, Including a Ca removal concentration step of sending the molten salt in the Ca concentration region whose concentration is increased to the reduction step, and as a molten salt for cleaning, a molten salt having a reduced Ca concentration in the Ca removal concentration step If used, the amount of Ca brought into the melting furnace can be significantly reduced. 1 is a preferred embodiment of the present invention.

  In the method for producing metal Ti or Ti alloy of the present invention, if cleaning of the mixture of Ti grains or Ti alloy grains and Ca-containing molten salt is performed in the separation step, the amount of Ca brought into the melting furnace by washing can be reduced. It is desirable because it can be performed efficiently.

In the method for producing metallic Ti or Ti alloy of the present invention can take an embodiment using a molten CaCl ₂ as the molten salt. 1 is a representative embodiment of the present invention.

  According to the method for producing metal Ti or Ti alloy of the present invention, a mixture of Ti grains or Ti alloy grains generated in the reduction step and Ca-containing molten salt is dissolved before melting by a relatively easy and inexpensive means. The amount of Ca brought into the melting furnace can be reduced to such an extent that it does not hinder the operation. As a result, in the melting process, problems such as adhesion of Ca on the inner wall of the melting furnace and the inner surface of the piping caused by the evaporation of Ca, blockage of the piping, etc. are avoided, and production of metal Ti by Ca reduction is performed for a long time Can be done continuously.

  The method for producing metal Ti or Ti alloy of the present invention is as described above, and in the method for producing metal Ti or Ti alloy by Ca reduction in a molten salt, Ti particles or Ti alloy particles produced in the reduction step and containing Ca The method is characterized in that the amount of Ca brought into the melting furnace is reduced by washing the mixture with the molten salt with the molten salt before melting to reduce the Ca concentration of the Ca-containing molten salt.

This production method includes a reduction step in which a metal chloride containing TiCl ₄ is continuously supplied into a molten salt containing CaCl ₂ and dissolved in Ca to produce Ti grains or Ti alloy grains in the molten salt, A separation step for separating the Ti particles or Ti alloy particles from the molten salt, a melting step for continuously dissolving the separated Ti particles or Ti alloy particles to form an ingot of metal Ti or Ti alloy, and Ti particles or Ti It includes an electrolysis process in which the Ca concentration is increased by electrolyzing the molten salt in which the Ca concentration has decreased along with the formation of alloy grains, and the molten salt generated in the electrolysis process in which the Ca concentration has been increased is reduced to TiCl _{4 in} the reduction process. In other words, the metal Ti or the Ti alloy produced by electrolysis of molten CaCl ₂ is used for the reduction of TiCl ₄ and the production of metal Ti or Ti alloy is continuously performed using this Ca. The premise is a Ti alloy manufacturing method (that is, OYIK method). This is because the metal Ti or Ti alloy production method of the present invention aims to reduce the amount of Ca brought into the melting furnace that hinders continuous operation in the OYIK method or a production process based on it. .

  In the method for producing metal Ti or Ti alloy according to the present invention, the amount of Ca brought into the melting furnace is reduced, as described above, by the Ti grains or Ti alloy grains to which the Ca-containing molten salt is adhered in the melting step. This is to prevent evaporation of Ca dissolved in the molten salt and adhesion to the inner wall of the melting furnace and the inner surface of the pipe when dissolving, and to eliminate the risk of oxidative combustion. Therefore, in the method of the present invention, the mixture of the Ti grains or Ti alloy grains generated in the reduction step and the Ca-containing molten salt is washed with the molten salt to reduce the Ca concentration of the Ca-containing molten salt.

As the molten salt used for washing, it is economically advantageous to use a part of the molten salt circulated between the steps in the production process. In that case, actually, a molten salt having a Ca concentration lower than the Ca concentration of the attached molten salt is used. For example, molten CaCl ₂ having a low Ca concentration is obtained in the Ca removal region 7 of the Ca removal and concentration device 5 in the manufacturing process of the metal Ti or Ti alloy shown in FIG. 1 to be described later, but this molten salt can be used. .

  In addition, there is a case where a molten salt is newly prepared for the purpose of supplementing the molten salt to the manufacturing process, and in this case, if a molten salt before containing (dissolving) Ca is used, Ca is included. Therefore, the Ca reduction effect by washing is great.

  If the Ca concentration of the molten salt used for cleaning is less than 1/5 of the Ca concentration of the Ca-containing molten salt adhering to the Ti grains, the effect of reducing the Ca concentration by cleaning is large, and the melting furnace This is desirable because the amount of Ca brought into can be reduced to a level that does not hinder continuous operation.

  The limit amount of Ca brought into the melting furnace must be determined after accumulating a certain amount of operation results, but the Ca concentration of the molten salt used for cleaning is that of the Ca-containing molten salt adhering to the Ti grains. For example, if the concentration is less than 1/5 of the Ca concentration, the amount of Ca brought into the melting furnace will be less than 1/5 assuming that the entire amount of the adhering molten salt is replaced by the molten salt for cleaning. The amount of Ca brought into the melting furnace can be greatly reduced. Therefore, it can be said that the amount of Ca can be reduced to such an extent that it does not become a hindrance to continuous operation depending on the regulation of the Ca concentration of the molten salt used for cleaning. In practice, the Ca concentration is often used at 0.1% by mass or less, and if it is about this level, even if it is brought into the melting furnace, it is unlikely that it will cause a significant operational problem.

  Washing with a molten salt of a mixture of Ti grains or Ti alloy grains and a Ca-containing molten salt may be performed at any stage before charging into the melting furnace in the melting step. However, if it is performed in the separation step, the separation of the Ca-containing molten salt proceeds, and in particular, at the final stage of the same step, the Ca-containing molten salt is only attached to the Ti grains or Ti alloy grains. In addition, since the cleaning effect can be enhanced with a small amount of the molten salt for cleaning, the amount of Ca brought into the melting furnace can be efficiently reduced, which is desirable.

  In the separation step, it is desirable that the Ti concentration (Ti content ratio in the mixture) of the mixture of Ti grains or Ti alloy grains and the Ca-containing molten salt is 10% by mass or more. More desirably, it is 20% by mass or more. In the melting step, the entire amount of the mixture of Ti grains or Ti alloy grains and the Ca-containing molten salt is melted to float and separate the Ca-containing molten salt, so that the Ti content ratio is high and the Ca-containing molten salt ratio is low. Energy efficiency becomes high and the amount of Ca charged into the melting furnace can be kept low. Said 10% by mass is the lower limit of the energy efficiency that is currently acceptable.

  A method for washing a mixture of Ti grains or Ti alloy grains and a Ca-containing molten salt with the molten salt is not particularly defined. An appropriate method should be taken according to the stage of washing, the state of the mixture, and the like. For example, when washing is performed at a stage where the amount of Ca-containing molten salt in the mixture is relatively large, it is necessary to perform a plurality of operations of adding and removing the molten salt for washing to the mixture in order to obtain a predetermined effect. . In the case of washing at the final stage of the separation process, the Ca-containing molten salt is only adhered to the Ti grains or Ti alloy grains, and the washing effect can be obtained by passing the washing molten salt slowly once through the mixture. Is obtained.

In the method for producing metal Ti or Ti alloy according to the present invention, as a molten salt for proceeding the reduction reaction of TiCl ₄ , that is, a molten salt containing CaCl ₂ and dissolved in Ca, in particular, only molten CaCl ₂ in which Ca is dissolved. It is desirable to take the embodiment used. Since the composition of the molten salt (bath salt) is simple, management of the bath salt such as dissolved Ca concentration and temperature is easy, and the operation can be performed more smoothly.

  In the manufacturing method of the metal Ti or Ti alloy of the present invention, if the manufacturing process as a premise further includes a Ca removal concentration step, as described below, as a molten salt for cleaning, Moreover, a molten salt having a significantly reduced Ca concentration can be used.

  This embodiment is a particularly desirable embodiment in the method for producing metal Ti or Ti alloy of the present invention. As a molten salt used for cleaning a mixture of Ti grains or Ti alloy grains and a Ca-containing molten salt, a molten salt having a very low Ca concentration and a part of the circulating molten salt in the production process is used. The reduction effect is large, it can be carried out relatively easily, and is economically advantageous. Hereinafter, this embodiment will be described with reference to the drawings.

  FIG. 1 is a diagram showing a schematic configuration example of an apparatus including a Ca removal and concentration step used in the implementation of the method for producing metal Ti or Ti alloy of the present invention.

As shown in FIG. 1, this apparatus holds a molten salt containing CaCl ₂ and dissolved in Ca (for example, molten CaCl ₂ dissolved in Ca), and a metal chloride containing TiCl ₄ in the molten CaCl ₂ . (here, the only TiCl ₄₎ and reduction vessel 1 for generating the Ti particles was continuously fed into the molten CaCl _2, and separating means 2 for separating the generated Ti particles from the molten CaCl _2, Dissolving means 3 for continuously dissolving the separated Ti particles to form a metal Ti ingot 20 and an electrolytic cell for increasing the Ca concentration by electrolyzing molten CaCl ₂ in which the Ca concentration is reduced as the Ti particles are generated. 4.

  Furthermore, this apparatus is equipped with the Ca removal concentration apparatus 5 and the adjustment tank 6 newly developed by the present inventors (for example, Japanese Patent Application No. 2006-65838), and the liquid cyclone 13 and a wire mesh are used as the separation means 2. A filter separator 14 is used (Japanese Patent Application No. 2006-271787).

The Ca removal concentration device 5 is in contact with the Ca removal region 7, the Ca concentration region 8 separated from the region 7 by the partition wall 9, and the molten CaCl ₂ in the Ca removal region 7 and the Ca concentration region 8. alloys (e.g., molten Mg-Ca alloy) has a molten alloy holding area for holding, removing the Ca dissolved in the molten CaCl ₂ in Ca removal area 7, melting CaCl ₂ in Ca concentration region 8 It has a function of concentrating Ca. That is, by applying a voltage lower than the decomposition voltage of CaCl ₂ so that the electrode plate on the Ca removal region 7 side becomes a positive electrode with respect to the electrode plate on the Ca concentration region 8 side, the molten CaCl in the Ca removal region 7 is applied. _The Ca dissolved in ₂ moves to the molten Mg—Ca alloy electrode 10 side and the concentration of dissolved Ca in the Ca removal region 7 decreases, while the Ca in the molten Mg—Ca alloy electrode 10 decreases to the Ca concentrated region 8. The concentration of dissolved Ca in the Ca concentration region 8 increases by moving to the molten CaCl ₂ side.

The adjustment tank 6 is a tank in which a Ca supply source 12 such as molten metal Ca or molten Mg—Ca alloy is floated on the upper layer of the molten CaCl ₂ 11 introduced into the tank 6, and the Ca concentration of the molten CaCl ₂ 11 is increased. If it is less than the saturation solubility, Ca can be supplied from the Ca supply source 12 to the molten CaCl ₂ 11 to maintain the Ca concentration at a concentration near the saturation solubility, and the Ca concentration of the molten CaCl ₂ 11 When the saturation solubility is exceeded and the precipitated metallic Ca is also present, the metallic Ca floats and is separated, and the Ca concentration is maintained at a concentration near the saturation solubility. As a result, the Ca concentration of the molten CaCl ₂ 11 supplied to the reduction tank 6 can be kept constant, the reduction in the reduction reaction efficiency of TiCl ₄ can be suppressed, and stable operation can be performed.

Further, by using the liquid cyclone 13 as the separation means 2, granulation of fine Ti particles generated in the molten CaCl ₂ in the reduction process proceeds, and at the same time, a part of the molten CaCl ₂ is separated upward, Concentrated. The granulated Ti particles are discharged together with the remaining molten CaCl ₂ from below the hydrocyclone 13, and the molten CaCl ₂ is removed by the filtration separator 14, and concentrated and separated.

The apparatus is provided with a cleaning molten CaCl ₂ tank 15 for storing a part of the molten CaCl ₂ held in the Ca removal region 7 of the Ca removal and concentration apparatus 5 and having a reduced concentration of dissolved Ca. ing.

The method for producing the metal Ti or Ti alloy of the present invention using the apparatus shown in FIG. 1 will be described by taking as an example the case of using molten CaCl ₂ as the molten salt.

First, molten CaCl ₂ continuously supplied from the electrolytic cell 4 through the adjusting tank 6 is held in the reduction tank 1, and TiCl ₄ (from the TiCl ₄ supply port 16 is supplied to Ca in the molten salt. Here, TiCl ₄ is used as a metal chloride) to react, and Ti particles are generated in the molten salt (reduction step).

The fine Ti particles generated in the molten CaCl ₂ in the reduction step are granulated by the liquid cyclone 13 in the separation step, and separated and concentrated. The granulated Ti particles are discharged together with the remaining molten CaCl ₂ from below the hydrocyclone 13. The discharged Ti particles are concentrated and separated by removing the molten CaCl ₂ by the filter separator 14.

  The Ti particles after separation are continuously heated and melted by the plasma irradiated from the plasma torch 18 in the separation tank 17 of the melting furnace, and poured into the mold 19 to become a Ti ingot 20.

In the separation process, the molten CaCl ₂ separated by the hydrocyclone 13, filtration separator 14 molten CaCl ₂ was removed in, and molten CaCl ₂ separated as an upper layer in the separating tank 17 by heat melting by plasma torch 18, They are sent to the Ca removal area 7 of the Ca concentration removal device 5 through the paths La, Lb, and Lc, respectively. Incidentally, path Ld, the route La, since the molten CaCl ₂ passing through the Lb is overwhelmingly larger than that of the molten CaCl ₂ passing through the path Lc, in Ca removal area 7 of the molten CaCl ₂ and Ca concentration region 8 This is a path for continuously performing the Ca removal and concentration process in the Ca removal and concentration apparatus 5 while taking a quantitative balance of the molten CaCl ₂ .

The molten CaCl ₂ in the Ca removal region 7 from which Ca has been removed (causing chlorine and back reaction generated at the anode) which adversely affects electrolysis in the Ca removal and concentration device 5 is sent to the electrolysis process and electrolyzed to form Ca. Concentration is increased. The electrolytic cell 4 includes a cylindrical electrolytic cell container 21 that holds a molten salt, a cylindrical anode 22 and a columnar cathode 23, similarly to the electrolytic cell described in Patent Document 2 described above. The molten CaCl ₂ that is continuously supplied between the anode 22 and the cathode 23 from the lower end of the electrolytic cell 4 is electrolyzed to extract the molten CaCl ₂ enriched in Ca. It is configured to be able to.

  Ca generated by electrolysis in the electrolysis step is introduced into the adjustment tank 6 having a Ca supply source together with the molten salt, and after the Ca concentration of the molten salt is made constant, the Ca is introduced into the reduction tank 1 and the metal Ti. Are continuously manufactured.

In the method for producing metal Ti or Ti alloy of the present invention, a part of the molten CaCl ₂ in the Ca removal region 7 sent to the electrolysis process is stored in the cleaning molten CaCl ₂ tank 15. A mixture of molten CaCl ₂ containing Ti particles and Ca are most of the molten CaCl ₂ filtration separator 14 through the hydrocyclone 13 is removed, a mixture of molten CaCl ₂ containing the Ti particles and Ca , washed with pooled molten CaCl ₂ in cleaning molten CaCl ₂ tank 15 of the. Since the molten CaCl ₂ is usually removed to a concentration of about 0.01%, the Ca concentration of the molten CaCl ₂ containing Ca in the mixture is reduced to about 0.01% by washing. It becomes possible.

  In this example, washing of the mixture of Ti grains and Ca-containing molten salt is performed in the separation step and in the final stage (filter separator 14). The filter separator 14 has a cylindrical shape, and a helical fin is attached to the inner wall of the tube (tube). Further, a fine wire mesh is stretched near the inside of the inner wall. It is inclined slightly upward and is configured to be rotatable about the axis of the cylinder. Most of the Ca-containing molten salt in the mixture discharged from below the hydrocyclone 13 passes through the wire mesh while being processed by the filter separator 14, moves to the inlet side of the filter separator 14, is discharged, and is discharged. The upper Ti particles or Ti alloy particles are pushed up by the helical fins as the filter separator 14 rotates, and are discharged from the outlet side.

Since the molten CaCl ₂ most liquid cyclone 13 and filter separator 14 is removed, the amount of molten CaCl ₂ of molten CaCl ₂ bath 15 used for washing may be a minimum, Ca amount being brought into the melting furnace Can be efficiently reduced.

  If the liquid cyclone 13 and the filter separator 14 shown in FIG. 1 are used as the separating means, the above-mentioned desirable condition of “Ti concentration of 10% by mass or more” can be sufficiently achieved.

In addition, the above-described desirable conditions for the Ca concentration of the molten salt used for cleaning (the concentration of less than 1/5 of the Ca concentration of the Ca-containing molten salt adhering to the Ti grains) are also shown in FIG. This is achievable with the use of an apparatus. Specifically, the Ca concentration of the molten salt discharged together with the Ti grains from the reduction tank 1 is about 0.05 to 0.30%, while the molten CaCl from which Ca has been removed in the Ca removal region 7. The Ca concentration of ₂ is about 0.01% under normal operating conditions, and it is sufficiently possible to satisfy the desirable conditions described above.

  As described above, the method for producing metal Ti or Ti alloy according to the present invention includes a mixture of Ti grains or Ti alloy grains produced in the reduction step and a Ca-containing molten salt in the molten salt, particularly in the production process. In this method, the amount of Ca brought into the melting furnace in the melting step is reduced by washing with molten salt circulating between the steps to lower the Ca concentration of the Ca-containing molten salt. According to this method, it is possible to reduce the amount of Ca brought into the melting furnace to a level that does not hinder the operation by relatively easy and inexpensive means, and the melting caused by the evaporation of Ca. The production of metal Ti or Ti alloy by Ca reduction can be continuously performed for a long time without causing problems such as adhesion of Ca on the inner wall of the furnace and the inner surface of the pipe, and blockage of the pipe.

  According to the method for producing metal Ti or Ti alloy of the present invention, the amount of Ca brought into the melting furnace is reduced, and Ca adheres to the inner wall of the melting furnace and the inner surface of the piping caused by the evaporation of Ca in the melting process. Further, problems such as blockage of piping can be avoided by relatively easy and inexpensive means, and the production of metal Ti by Ca reduction can be continuously performed over a long period of time.

  Therefore, the method for producing metal Ti or Ti alloy of the present invention can be effectively used as a method for continuously producing metal Ti or Ti alloy by Ca reduction.

It is a figure which shows the example of schematic structure of the apparatus used for implementation of the manufacturing method of the metal Ti or Ti alloy of this invention.

Explanation of symbols

1: Reduction tank 2: Separation means 3: Dissolution means 4: Electrolysis tank 5: Ca removal concentration apparatus 6: Adjustment tank 7: Ca removal area 8: Ca concentration area 9: Partition 10: Molten Mg-Ca alloy electrode 11: Melting CaCl ₂
12: Ca supply source 13: Hydrocyclone 14: Filtration separator 15: Melting CaCl ₂ tank 16 for cleaning 16: TiCl ₄ supply port 17: Separation tank 18: Plasma torch 19: Mold 20: Ti ingot 21: Electrolyzer container 22: Anode 23: Cathode 24: Diaphragm

Claims (5)

A reduction step of continuously supplying a metal chloride containing TiCl ₄ into a molten salt containing CaCl ₂ and dissolving Ca to produce Ti grains or Ti alloy grains in the molten salt, and the produced Ti grains or Ti Separation process for separating the alloy grains from the molten salt, a melting process for continuously melting the separated Ti grains or Ti alloy grains to form an ingot of metal Ti or Ti alloy, and generation of the Ti grains or Ti alloy grains In addition, an electrolysis process for increasing the Ca concentration by electrolyzing the molten salt having a reduced Ca concentration is used, and the molten salt generated in the electrolysis process is used for the reduction of TiCl _{4 in} the reduction process. Or in the method for producing a Ti alloy,
A mixture of Ti grains or Ti alloy grains produced in the reduction step and a Ca-containing molten salt is washed with molten salt before melting, thereby reducing the Ca concentration of the Ca-containing molten salt and bringing the Ca into the melting furnace. A method for producing metal Ti or a Ti alloy, characterized in that the amount is reduced.   2. The method for producing metal Ti or Ti alloy according to claim 1, wherein a molten salt having a Ca concentration lower than that of the Ca-containing molten salt produced in the reduction step is used as the molten salt for cleaning. The method for producing metal Ti or Ti alloy according to claim 1, further comprising: a Ca plate in which a molten salt side electrode plate in a Ca removal region holding the molten salt separated in the separation step is separated from the region. By applying a voltage lower than the decomposition voltage of CaCl ₂ so as to be a positive electrode with respect to the electrode plate on the molten salt side in the concentration region, the molten salt in the Ca removal region in which the Ca concentration is reduced is subjected to the electrolysis process. Including a Ca removal concentration step of sending the molten salt in the Ca concentration region where Ca is concentrated to the reduction step,
The method for producing metal Ti or Ti alloy according to claim 1, wherein a molten salt having a reduced Ca concentration in a Ca removal and concentration step is used as the cleaning molten salt.   The method for producing metal Ti or Ti alloy according to any one of claims 1 to 3, wherein the mixture of the Ti grains or Ti alloy grains and the Ca-containing molten salt is washed in a separation step. Method for producing a metallic Ti or Ti alloy according to claim 1, wherein the molten salt is characterized by comprising the molten CaCl _2.

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