Manufacturing method of titanium tetrachloride

Abstract

To provide a manufacturing method of titanium tetrachloride efficiently for an extended period.SOLUTION: In a titanium tetrachloride manufacturing device 1 assembled with a container 10, a bottom plate 11 partitioning the container to a lower side space S1 and an upperside space S2 and having a plurality of vent holes 11a, a gas introduction hole 12 for introducing a chlorine gas to the lower side space, and a dispersion layer 18 arranged on the upper side of the bottom plate and constituted of an initial non-active solid particle, provided herein is a titanium tetrachloride manufacturing method for manufacturing titanium tetrachloride by chemical reaction of chlorine gas to a fluid bed 19 arranged on the upper side of the dispersion layer and constituted of an initial titanium raw material 19a and an initial coke 19b. The titanium tetrachloride manufacturing method includes introducing chlorine gas to a gas introduction hole, supplying an additional titanium raw material and an additional coke to the fluid bed, and supplying additional non-active solid particles to the fluid bed in response to a decrease in the dispersion layer.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a method for producing titanium tetrachloride. [Background technology]

[0002] Patent Document 1 discloses a fluidized chlorination furnace for producing titanium tetrachloride from a raw material containing titanium oxide, coke, and chlorine gas. The fluidized chlorination furnace is equipped with a bottom plate, a heat insulating layer made of monolithic refractory material placed on the upper surface of the bottom plate, and a distributor having a dispersion layer made of chlorine-resistant inert particles on the upper surface of the heat insulating layer. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2014-210689 Summary of the Invention [Problem to be solved by the invention]

[0004] According to the fluidized chlorination furnace of Patent Document 1, by placing a heat insulating layer on the upper surface of the bottom plate, corrosion of the bottom plate due to chlorine gas can be suppressed, and titanium tetrachloride can be produced stably over a long period of time.

[0005] On the other hand, when titanium tetrachloride is produced for a long period of time, the dispersion layer may be corroded and worn away by chlorine gas, making it difficult to continuously disperse chlorine gas. In such cases, it becomes difficult to efficiently produce titanium tetrachloride for a long period of time. Therefore, there is room for improvement in the method for producing titanium tetrachloride from the viewpoint of efficiently producing titanium tetrachloride for a long period of time.

[0006] To provide a method for producing titanium tetrachloride, which can continuously disperse chlorine gas in a dispersion layer even when titanium tetrachloride is produced for a long period of time. [Means for solving the problem]

[0007] The present disclosure provides: A method for producing titanium tetrachloride comprising: a vessel; a bottom plate dividing the inside of the vessel into a lower space and an upper space and having a plurality of vent holes; a gas inlet hole for introducing chlorine gas into the lower space; and a dispersion layer disposed above the bottom plate and made of initial inert solid particles, the method comprising producing titanium tetrachloride by chemically reacting the chlorine gas in a fluidized bed disposed above the dispersion layer and made of initial titanium raw material and initial coke, the method comprising: introducing the chlorine gas through the gas inlet; supplying additional titanium material and additional coke to the fluidized bed; supplying additional inert solid particles to the fluidized bed as the dispersed bed decreases; The present invention provides a method for producing titanium tetrachloride, comprising:

[0008] According to the method for producing titanium tetrachloride of the present disclosure, the supply of additional inert solid particles can increase the dispersion layer that is reduced by chemical reaction with chlorine gas, so that chlorine gas can be continuously dispersed in the dispersion layer even when titanium tetrachloride is produced for a long period of time, thereby enabling titanium tetrachloride to be produced efficiently for a longer period of time. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a vertical cross-sectional view of a titanium tetrachloride manufacturing apparatus according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings.

[0011] Fig. 1 shows a vertical cross-sectional view of a titanium tetrachloride production apparatus 1 according to this embodiment. In Fig. 1, the titanium tetrachloride production apparatus 1 extends in the vertical direction. In this specification, the vertical direction of the titanium tetrachloride production apparatus 1 is referred to as the up-down direction. Furthermore, in this specification, the lengths of the dispersion layer and the fluidized layer refer to the lengths in the up-down direction.

[0012] The titanium tetrachloride manufacturing apparatus 1 is an apparatus for manufacturing titanium tetrachloride, which is a precursor of titanium products such as titanium sponge and titanium ingots. In the titanium tetrachloride manufacturing apparatus 1, titanium tetrachloride is produced by chemically reacting titanium raw material and coke with chlorine gas.

[0013] As shown in Figure 1, the titanium tetrachloride manufacturing apparatus 1 has a cylindrical vessel 10 composed of a bottom wall 10a, a cylindrical side wall 10b extending upward from the bottom wall 10a, and an upper wall 10c covering the upper end of the side wall 10b, and a bottom plate 11 dividing the inside of the vessel 10 into a lower space S1 and an upper space S2. The side wall 10b of the lower space S1 is provided with a gas inlet hole 12 for introducing chlorine gas into the vessel 10. The side wall 10b of the upper space S2 is provided with a supply hole 13 for supplying titanium raw material and / or coke into the vessel 10. The upper wall 10c is provided with a discharge hole 14 through which the manufactured titanium tetrachloride is discharged.

[0014] The bottom plate 11 is fixed to the inside of the side wall 10b. For example, the bottom plate 11 is an iron plate having a thickness of 20 mm. The bottom plate 11 is provided with a plurality of ventilation holes 11a for guiding the chlorine gas introduced through the gas introduction holes 12 to the upper side of the bottom plate 11.

[0015] An insulating layer 17 is disposed above the bottom plate 11 to suppress heat transfer from the high-temperature titanium raw material that constitutes the fluidized bed 19, which will be described later, to the bottom plate 11. The insulating layer 17 is made of a non-aqueous monolithic refractory. The non-aqueous monolithic refractory is preferably a plastic refractory with a moisture content of 6% by mass or less before application. The insulating layer 17 is provided with a plurality of gas flow paths 17a for guiding chlorine gas flowing upward from the vent holes 11a to the upper side of the insulating layer 17.

[0016] A dispersion layer 18 is disposed above the heat insulating layer 17 to disperse the chlorine gas flowing upward from the gas flow passage 17a into the vessel 10. The dispersion layer 18 is composed of chlorine-resistant inert solid particles (for convenience, referred to as initial inert solid particles 18a). The initial inert solid particles 18a are silica (SiO), alumina (AlO), silicon nitride (SiN), or the like. The particle diameter of the initial inert solid particles 18a is 3 mm to 50 mm. Note that the particle diameters of the inert solid particles and the particle diameters of the titanium raw material and coke described below refer to the average particle diameter D50.

[0017] Above the dispersion layer 18, there is disposed a fluidized bed 19 composed of a titanium raw material (referred to as initial titanium raw material 19a for convenience) and coke (referred to as initial coke 19b for convenience), which are raw materials for producing titanium tetrachloride by chemical reaction with chlorine gas flowing from the dispersion layer 18. The titanium raw material is titanium ore containing titanium oxide. The coke is used as a reducing agent in the chemical reaction for producing titanium tetrachloride. The particle sizes of the titanium raw material and the coke are 100 μm to 3000 μm. During operation of the titanium tetrachloride production apparatus 1, the height of an interface 19c, which is the upper end of the fluidized bed 19, is controlled to be lower than the height of the supply holes 13 and to be approximately constant, although there are some fluctuations.

[0018] A first pressure measurement hole 15 communicating with the lower space S1 is provided in the side wall 10b of the lower space S1. A second pressure measurement hole 16 communicating with the fluidized bed 19 is provided in the side wall 10b of the upper space S2 where the fluidized bed 19 is disposed. The second pressure measurement hole 16 is located between the upper end of the dispersion layer 18 and the interface 19c of the fluidized bed 19 in the vertical direction. The first pressure measurement hole 15 and the second pressure measurement hole 16 are holes for measuring the pressures of the lower space S1 and the fluidized bed 19, respectively. For example, pressure measurement sensors A1 and A2 measure the pressures of the lower space S1 and the fluidized bed 19 in the container 10 via the measurement holes 15 and 16, respectively (see FIG. 1).

[0019] Next, a method for producing titanium tetrachloride using the titanium tetrachloride production apparatus 1 will be described.

[0020] As shown in Fig. 1, a dispersion layer 18 composed of initial inert solid particles 18a and a fluidized bed 19 composed of initial titanium raw material 19a and initial coke 19b (referred to as initial raw material) are arranged inside a vessel 10 of a titanium tetrachloride production apparatus 1. In the state shown in Fig. 1, the vessel 10 is maintained at a high temperature of 900°C to 1100°C to chemically react the initial raw material with chlorine gas.

[0021] Chlorine gas is introduced through the gas inlet hole 12 of the vessel 10, which is maintained at a high temperature, and passes through the vent hole 11a in the bottom plate 11 and the gas flow passage 17a in the heat insulating layer 17, and flows upward toward the dispersion layer 18. The chlorine gas that has reached the dispersion layer 18 flows through numerous gaps between the initial inert solid particles 18a that make up the dispersion layer 18. This allows the flow of chlorine gas to be dispersed in the planar direction. Therefore, the chlorine gas that has passed through the dispersion layer 18 and reached the fluidized bed 19 is dispersed approximately uniformly in the planar direction.

[0022] The chlorine gas that arrives in the fluidized bed 19 comes into contact with the initial raw materials that make up the fluidized bed 19 and undergoes a chemical reaction. Most of the chlorine gas is consumed by this chemical reaction, and gaseous titanium tetrachloride, carbon dioxide, carbon monoxide, etc. are produced. The products such as titanium tetrachloride and the remaining chlorine gas are discharged through the discharge hole 14 of the vessel 10. The discharged titanium tetrachloride is then cooled separately to become a liquid, and is separated from the other products. In this way, titanium tetrachloride is produced.

[0023] In the above process, the initial raw material is consumed by chemical reaction with chlorine gas, so that the interface 19c of the fluidized bed 19 gradually decreases. In the titanium tetrachloride manufacturing apparatus 1 of the present embodiment, in order to keep the interface 19c approximately constant, additional titanium raw material and additional coke (referred to as additional raw materials) are supplied to the fluidized bed 19 through the supply holes 13 of the vessel 10.

[0024] The additional titanium raw material and additional coke in this embodiment are the same as the initial titanium raw material 19a and initial coke 19b. Therefore, the additional raw material and the initial raw material are mixed in the fluidized bed 19 after the additional raw material has been supplied. In the titanium tetrachloride manufacturing apparatus 1, chlorine gas is continuously introduced into the vessel 10, and the titanium raw material and coke are continuously consumed, so the additional raw material is also basically continuously supplied. However, there may be cases where the supply of the additional raw material is temporarily stopped due to reasons such as equipment inspection.

[0025] The supply mass of the additional raw material is automatically or manually controlled according to fluctuations in the height of the interface 19c. The supply mass of the additional raw material per hour, calculated by dividing the supply mass of the additional raw material per day by 24 hours, is defined as the additional raw material supply rate M1.

[0026] On the other hand, the chlorine gas flowing through the dispersion layer 18 has already been heated by the high-temperature vessel 10 and is therefore at a high temperature, which corrodes and wears away the initial inert solid particles 18a in the dispersion layer 18. As a result, the particle size of the initial inert solid particles 18a decreases and they may eventually be worn away. For this reason, if the titanium tetrachloride production apparatus 1 is operated for a long period of time, the length of the dispersion layer 18 may decrease, and the chlorine gas may not be dispersed efficiently. If the chlorine gas is not dispersed efficiently, the chemical reaction with the titanium raw material and coke in the fluidized bed 19 may not occur uniformly in the planar direction, which may reduce the titanium tetrachloride production efficiency. The worn powder of the inert solid particles is discharged to the outside of the vessel 10 through the discharge hole 14.

[0027] In the method for producing titanium tetrachloride of this embodiment, additional inert solid particles are supplied to the fluidized bed 19 through the supply holes 13 as the length of the dispersion layer 18 decreases. Specifically, the additional inert solid particles are supplied through the supply holes 13 together with the continuously supplied additional raw material. The additional inert solid particles supplied to the fluidized bed 19 descend within the fluidized bed 19 by their own weight, arrive at the dispersion layer 18, and form a dispersion layer together with the initial inert solid particles 18a. As a result, the reduced length of the dispersion layer 18 increases again due to the supply of the additional inert solid particles. As a result, efficient dispersion of chlorine gas is maintained, and it may be possible to efficiently produce titanium tetrachloride for a longer period of time.

[0028] The material of the additional inert solid particles is preferably chlorine-resistant and may be the same as the material of the initial inert solid particles 18a. The particle size of the additional inert solid particles is preferably 3 mm or more and 50 mm or less, more preferably 10 mm or more and 30 mm or less. If the particle size of the additional inert solid particles is too small, the additional inert solid particles will have difficulty descending in the fluidized bed 19 due to their own weight and may be discharged through the discharge hole 14. If the particle size of the additional inert solid particles is too large, the gaps between the additional inert solid particles and between the additional inert solid particles and the initial inert solid particles 18a will become large, which may prevent efficient dispersion of chlorine gas.

[0029] Next, a method for supplying the additional inert solid particles will be described.

[0030] The amount of additional inert solid particles is preferably supplied in accordance with the amount of wear of the additional inert solid particles and / or the initial inert solid particles 18a in the dispersion layer 18. If the amount of additional inert solid particles supplied is too small compared to the amount of wear of the additional inert solid particles and / or the initial inert solid particles 18a, the length of the dispersion layer 18 may not increase as desired. If the amount of additional inert solid particles supplied is too large compared to the amount of wear of the additional inert solid particles and / or the initial inert solid particles 18a, the proportion of the dispersion layer 18 in the vessel 10 may increase excessively and the proportion of the fluidized bed 19 may decrease, which may result in a decrease in the amount of titanium tetrachloride produced. In addition, if an excessive amount of additional inert solid particles is supplied, the temperature of the additional inert solid particles is room temperature, which reduces the temperature inside the vessel 10 and makes it difficult for the chlorine gas to react with the titanium raw material and coke, which may result in a decrease in the amount of titanium tetrachloride produced.

[0031] The mass of the additional inert solid particles fed per hour is defined as the additional inert solid particle feed rate M2. The additional inert solid particle feed rate M2 indicates the mass of the additional inert solid particles fed per hour when they are continuously fed. The additional inert solid particle feed rate M2 is controlled so that the ratio M2 / M1 of the additional inert solid particle feed rate M2 to the additional raw material feed rate M1 is 0.01% or more and 30% or less. By controlling the additional inert solid particle feed rate M2 in this manner, the desired length of the dispersion layer 18 can be maintained without a decrease in the temperature inside the vessel 10.

[0032] That is, by maintaining the ratio M2 / M1 at 0.01% or more, the additional inert solid particles can be supplied so that the supply amount of the additional inert solid particles does not fall below the amount of loss. Also, by maintaining the ratio M2 / M1 at 30% or less, the additional inert solid particles can be supplied so as to suppress fluctuations in the ratio of the fluidized bed 19 to an extent that does not affect the production amount of titanium tetrachloride and to suppress fluctuations in the temperature inside the vessel 10 to an extent that does not affect the chemical reaction between the chlorine gas and the titanium raw material, etc.

[0033] Furthermore, the inventors have found that the pressure difference Pd between the first pressure P1 in the lower space S1 and the second pressure P2 in the fluidized bed 19 correlates with the amount of wear of the additional inert solid particles and / or the initial inert solid particles 18a, and that by determining the supply mass of the additional inert solid particles in accordance with the pressure difference Pd, the supply rate M2 of the additional inert solid particles can be controlled with higher precision, thereby ensuring that the additional inert solid particles are supplied without excess or deficiency.

[0034] The lower space S1 is filled mainly with chlorine gas introduced through the gas inlet hole 12. The gaps in the fluidized bed 19 are filled mainly with chlorine gas that has passed through the bottom plate 11, the insulating layer 17, the dispersion layer 18, and the fluidized bed 19, and the gas produced in the fluidized bed 19 (titanium tetrachloride, carbon monoxide, carbon dioxide, etc.). That is, the second pressure P2 is composed of the partial pressure of chlorine gas, the pressure of which has been reduced by passing through the bottom plate 11, the insulating layer 17, the dispersion layer 18, and the fluidized bed 19, and the partial pressure of the produced gas. The partial pressure of the produced gas also drops because the produced gas passes through the fluidized bed 19. For this reason, the second pressure P2 is lower than the first pressure P1.

[0035] As described above, the particle diameters of the titanium raw material and coke constituting the fluidized bed 19 are 100 μm to 3000 μm, and the particle diameters of the inert solid particles constituting the dispersion layer 18 are 3 mm to 50 mm. Therefore, the particle diameters of the titanium raw material, etc. in the fluidized bed 19 are smaller than the particle diameters of the inert solid particles in the dispersion layer 18. Therefore, the gaps between the titanium raw material and the coke in the fluidized bed 19 are smaller than the gaps between the inert solid particles in the dispersion layer 18. Since these gaps serve as flow paths for the chlorine gas, the smaller the gaps, the larger the pressure drop of the chlorine gas. Therefore, the pressure drop per unit length of the chlorine gas in the fluidized bed 19 is larger than the pressure drop per unit length of the chlorine gas in the dispersion layer 18.

[0036] Here, the length from the lower end of the dispersion layer 18 to the second pressure measurement hole 16 is referred to as pressure measurement length L1, the length of the dispersion layer 18 at pressure measurement length L1 (i.e., the length from the lower end to the upper end of the dispersion layer 18) is referred to as dispersion layer length L2, and the length of the fluidized bed 19 at pressure measurement length L1 (i.e., the length from the lower end of the fluidized bed 19 to the second pressure measurement hole 16) is referred to as fluidized bed length L3. As wear of the inert solid particles in the dispersion layer 18 progresses and the dispersion layer length L2 decreases, the fluidized bed length L3 increases. This increases the proportion of the fluidized bed 19, which experiences a relatively large pressure drop, so the pressure drop of the chlorine gas and the generated gas when the dispersion layer length L2 decreases is greater than the pressure drop when the dispersion layer 18 is maintained at the desired length. In other words, the pressure difference Pd when the dispersion layer length L2 decreases is greater than the pressure difference Pd when the dispersion layer 18 is maintained at the desired length.

[0037] On the other hand, if an excessive amount of additional inert solid particles is supplied, the dispersed bed length L2 increases and the fluidized bed length L3 decreases. The pressure drop at this time is smaller than the pressure drop when the dispersed bed 18 is maintained at the desired length. That is, the pressure difference Pd when the dispersed bed length L2 increases excessively is smaller than the pressure difference Pd when the dispersed bed 18 is maintained at the desired length.

[0038] In the titanium tetrachloride manufacturing apparatus 1 of this embodiment, a first pressure P1 is measured at the first pressure measurement hole 15, and a second pressure P2 is measured at the second pressure measurement hole 16. A differential pressure Pd is calculated by a separate external device based on the measured first pressure P1 and second pressure P2. The differential pressure Pd is a value obtained by subtracting the second pressure P2 from the first pressure P1. During operation of the titanium tetrachloride manufacturing apparatus 1, the differential pressure Pd is constantly calculated. The supply rate M2 of the additional inert solid particles is controlled so that the differential pressure Pd falls within a predetermined range.

[0039] The predetermined range is a range of ±15% of the reference differential pressure Pdb. The reference differential pressure Pdb is the differential pressure when the dispersion layer 18 is maintained at a desired length, for example, the differential pressure between the first pressure P1 and the second pressure P2 when the titanium tetrachloride manufacturing apparatus 1 starts operating in a state where the dispersion layer 18 is composed only of initial inert solid particles.

[0040] A range of ±15% of the reference differential pressure Pdb is a desirable range in which titanium tetrachloride can be produced efficiently. If the differential pressure Pd exceeds +15% of the reference differential pressure Pdb, the dispersion layer length L2 decreases, making it difficult to continuously disperse chlorine gas in the dispersion layer 18 for a long period of time. If the differential pressure Pd becomes less than -15% of the reference differential pressure Pdb, the dispersion layer length L2 increases excessively, thereby reducing the fluidized bed length L3 and potentially reducing the amount of titanium tetrachloride produced.

[0041] For example, when the differential pressure Pd exceeds +15% of the reference differential pressure Pdb in a situation where the additional inert solid particles are not being supplied, the additional inert solid particles start to be supplied to the fluidized bed 19. Thereafter, the differential pressure Pd approaches the reference differential pressure Pdb and becomes +15% or less of the reference differential pressure Pdb, so that the desired length of the dispersed bed 18 can be maintained.

[0042] For example, when the pressure difference Pd exceeds +15% of the reference pressure difference Pdb while the additional inert solid particles are being supplied, the mass of the additional inert solid particles supplied increases, i.e., the supply rate M2 of the additional inert solid particles increases. Thereafter, the pressure difference Pd approaches the reference pressure difference Pdb and becomes equal to or less than +15% of the reference pressure difference Pdb, thereby maintaining the dispersion layer 18 at a desired length.

[0043] On the other hand, for example, when the additional inert solid particles are being supplied, if the differential pressure Pd becomes less than -15% of the reference differential pressure Pdb, the supply rate M2 of the additional inert solid particles is reduced or the supply of the additional inert solid particles is stopped. Thereafter, the differential pressure Pd approaches the reference differential pressure Pdb and becomes -15% or more of the reference differential pressure Pdb, thereby maintaining the dispersion layer 18 at a desired length.

[0044] The additional inert solid particles may be supplied continuously or intermittently as long as the differential pressure Pd is within ±15% of the reference differential pressure Pdb. The control of the additional inert solid particle supply rate M2 is performed automatically or manually. For example, a control unit may be provided that determines the additional inert solid particle supply rate M2 based on the differential pressure Pd calculated by a separate external device. The additional inert solid particles may be automatically supplied by a separate external supply device based on the additional inert solid particle supply rate M2 determined by this control.

[0045] By controlling the additional inert solid particle supply rate M2 in this manner, it becomes possible to produce titanium tetrachloride efficiently for a longer period of time.

[0046] The method for producing titanium tetrachloride according to this embodiment has the following advantages.

[0047] (1) A method for producing titanium tetrachloride in an apparatus 1 for producing titanium tetrachloride, the apparatus 1 comprising a vessel 10, a bottom plate 11 dividing the inside of the vessel 10 into a lower space S1 and an upper space S2 and having a plurality of vent holes 11a, a gas inlet hole 12 for introducing chlorine gas into the lower space S1, and a dispersion layer 18 arranged above the bottom plate 11 and made up of initial inert solid particles 18a, the method comprising: producing titanium tetrachloride by chemically reacting chlorine gas in a fluidized bed 19 arranged above the dispersion layer 18 and made up of initial titanium raw material 19a and initial coke 19b; introducing chlorine gas through the gas inlet hole 12; supplying additional titanium material and additional coke to the fluidized bed (19); Supplying additional inert solid particles to the fluidized bed 19 as the dispersed bed 18 decreases Equipped with.

[0048] As a result, even if the inert solid particles are worn away by contact with chlorine gas, it is easy to maintain the desired length of dispersion layer 18 by supplying additional inert solid particles. This allows chlorine gas to be continuously dispersed in dispersion layer 18, making it possible to efficiently produce titanium tetrachloride over a long period of time.

[0049] (2) The particle size of the additional inert solid particles is not less than 3 mm and not more than 50 mm. Since the particle size of the additional inert solid particles is 3 mm or more, the additional inert solid particles can easily descend within the fluidized bed 19 and form the dispersion layer 18. Furthermore, since the particle size of the additional inert solid particles is 50 mm or less, gaps between the inert solid particles in the dispersion layer 18 can be suitably formed, and the chlorine gas can be efficiently dispersed.

[0050] (3) The ratio M2 / M1 of the additional inert solid particle feed rate M2, which is the mass of additional inert solid particles fed per hour, to the additional raw material feed rate M1, which is the mass of additional titanium raw material and additional coke fed per day divided by 24 hours, is 0.01% or more and 30% or less.

[0051] By setting the ratio M2 / M1 to 0.01% or more, the dispersion layer length L2, which has decreased due to wear of the inert solid particles, can be increased to a desired length. Furthermore, by setting the ratio M2 / M1 to 30% or less, a decrease in the proportion of the fluidized bed 19 in the vessel 10 and a decrease in the temperature inside the vessel 10 can be suppressed, making it easier to maintain efficient production of titanium tetrachloride.

[0052] (4) The titanium tetrachloride manufacturing method is Measuring a first pressure P1 in the lower space S1; Measuring a second pressure P2 in the fluidized bed 19; The additional inert solid particle supply rate M2, which is the supply mass of the additional inert solid particles per hour, is controlled so that the pressure difference Pd between the first pressure P1 and the second pressure P2 falls within a predetermined range. Further provided are:

[0053] As a result, the supply rate M2 of the additional inert solid particles can be controlled more accurately, so that the additional inert solid particles can be supplied in just the right amount.

[0054] The method for producing titanium tetrachloride according to the present disclosure is not limited to the configuration of the above embodiment, and various modifications are possible.

[0055] Although the additional inert solid particles are supplied from the supply holes 13 together with the additional raw material, they may be supplied separately from the additional raw material. For example, the additional inert solid particles may be supplied from the supply holes 13 while the supply of the additional raw material is temporarily stopped. Alternatively, the additional inert solid particles may be supplied from a dedicated supply hole provided separately from the supply holes 13.

[0056] Although the titanium tetrachloride manufacturing apparatus 1 of this embodiment has the heat insulating layer 17, it does not have to have the heat insulating layer 17. If the titanium tetrachloride manufacturing apparatus 1 does not have the heat insulating layer 17, the dispersion layer 18 is arranged above the bottom plate 11, and the fluidized bed 19 is arranged above the dispersion layer 18. That is, chlorine gas passes through the vent hole 11a of the bottom plate 11, flows into the dispersion layer 18, and then reaches the fluidized bed 19.

[0057] Even when the interface 19c of the fluidized bed 19 is located below the second pressure measurement hole 16 during operation of the titanium tetrachloride manufacturing apparatus 1, the supply rate M2 of the additional inert solid particles may be controlled based on the differential pressure Pd.

[0058] [Note] The method for producing titanium tetrachloride according to the present disclosure provides the following aspects.

[0059] [Aspect 1] A method for producing titanium tetrachloride comprising: a vessel; a bottom plate dividing the inside of the vessel into a lower space and an upper space and having a plurality of vent holes; a gas inlet hole for introducing chlorine gas into the lower space; and a dispersion layer disposed above the bottom plate and made of initial inert solid particles, the method comprising producing titanium tetrachloride by chemically reacting the chlorine gas in a fluidized bed disposed above the dispersion layer and made of initial titanium raw material and initial coke, the method comprising: introducing the chlorine gas through the gas inlet; supplying additional titanium material and additional coke to the fluidized bed; supplying additional inert solid particles to the fluidized bed as the dispersed bed decreases; A method for producing titanium tetrachloride, comprising:

[0060] [Aspect 2] The particle size of the additional inert solid particles is 3 mm or more and 50 mm or less. 2. The method for producing titanium tetrachloride according to claim 1.

[0061] [Aspect 3] a ratio of an additional inert solid particle feed rate, which is the mass of the additional inert solid particles fed per hour, to an additional raw material feed rate, which is the mass of the additional titanium raw material and the additional coke fed per day divided by 24 hours, is 0.01% or more and 30% or less; 3. The method for producing titanium tetrachloride according to claim 1 or 2.

[0062] [Aspect 4] The method for producing titanium tetrachloride comprises: measuring a first pressure in the lower space; measuring a second pressure in the fluidized bed; controlling a supply rate of the additional inert solid particles, which is a supply mass of the additional inert solid particles per hour, so that the differential pressure between the first pressure and the second pressure falls within a predetermined range; The method for producing titanium tetrachloride according to any one of aspects 1 to 3, further comprising: [Explanation of symbols]

[0063] 1: Titanium tetrachloride manufacturing equipment 10: Container 10a: Bottom wall 10b: Side wall 10c: Upper wall 11: Bottom plate 11a: Ventilation hole 12: Gas inlet hole 13: Supply hole 14: Discharge hole 15: First pressure measurement hole 16: Second pressure measurement hole 17: Heat insulating layer 17a: Gas flow path 18:Dispersion layer 18a: Initial inert solid particles 19: Fluidized bed 19a: Initial titanium raw material 19b: Early coke 19c: Interface S1: Lower space S2: Upper space L1: Pressure measurement length L2: Dispersion layer length L3: fluidized bed length A1, A2: Pressure measurement sensors

Claims

1. A method for producing titanium tetrachloride comprising: a vessel; a bottom plate dividing the inside of the vessel into a lower space and an upper space and having a plurality of vent holes; a gas inlet hole for introducing chlorine gas into the lower space; and a dispersion layer disposed above the bottom plate and made of initial inert solid particles, the method comprising producing titanium tetrachloride by chemically reacting the chlorine gas in a fluidized bed disposed above the dispersion layer and made of initial titanium raw material and initial coke, the method comprising: introducing the chlorine gas through the gas inlet; supplying additional titanium material and additional coke to the fluidized bed; supplying additional inert solid particles to the fluidized bed as the dispersed bed decreases; A method for producing titanium tetrachloride, comprising:

2. The particle size of the additional inert solid particles is 3 mm or more and 50 mm or less.

2. The method for producing titanium tetrachloride according to claim 1.

3. a ratio of an additional inert solid particle feed rate, which is the mass of the additional inert solid particles fed per hour, to an additional raw material feed rate, which is the mass of the additional titanium raw material and the additional coke fed per day divided by 24 hours, is 0.01% or more and 30% or less; 3. The method for producing titanium tetrachloride according to claim 1 or 2.

4. The method for producing titanium tetrachloride comprises: measuring a first pressure in the lower space; measuring a second pressure in the fluidized bed; controlling a supply rate of the additional inert solid particles, which is a supply mass of the additional inert solid particles per hour, so that the differential pressure between the first pressure and the second pressure falls within a predetermined range; The method for producing titanium tetrachloride according to claim 1 or 2, further comprising:

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