Novel titanium sponge feeding process

Abstract

The invention relates to the technical field of titanium sponge processing, in particular to a novel titanium sponge feeding process which comprises the following steps: S1, checking the air tightness of a reduction furnace and a reactor, and heating four heating areas of the reactor from top to bottom to preset temperature; s2, after the temperature is reached, starting a first feeding stage; s3, after the time reaches a specified value, starting a second feeding stage; s4, after the time reaches a specified value, starting a third feeding stage; s5, when the feeding amount of titanium tetrachloride reaches a preset value, the reduction reaction is finished; and S6, carrying out subsequent distillation and crushing processes. According to the novel titanium sponge feeding process, the problem that the temperature in the middle stage of reaction is too high is effectively solved, the titanium tetrachloride and the liquid magnesium are added in a parallel-flow mode, the original method that all the liquid magnesium is added into a reactor at a time is abandoned, and the liquid magnesium is added step by step, so that the space of the reactor is sufficient, and heat dissipation is more sufficient; therefore, the temperature in the middle stage of reaction is effectively reduced.

Description

Technical Field

[0001] The invention relates to the technical field of titanium sponge processing, in particular to a novel titanium sponge feeding process. Background Art

[0002] Titanium is widely used in aerospace, ships, petroleum, chemical industry, light industry, electric power, nuclear power plants and many other fields due to its low density, high strength, high and low temperature resistance, corrosion resistance and other excellent properties. At present, the main process for producing titanium sponge is magnesium thermal reduction method (Kroll method), which mainly includes chlorination, refining, reduction, distillation, magnesium electrolysis and crushing. Among them, the reduction process, as the main reaction step, determines the formation form of titanium sponge, while the distillation process is the main impurity removal process, which determines the grade of the finished product.

[0003] In the traditional reduction process, the initial method is to add liquid magnesium and all titanium tetrachloride into the reactor together, but because the reaction is too violent, it is easy to explode. Therefore, later it was changed to add all the required liquid magnesium into the reactor first, and then add titanium tetrachloride according to a specific addition curve. However, this method has a significant drawback, that is, the temperature is easy to be too high in the middle of the reaction. Although an air cooling device is installed, the cooling effect is not ideal. Excessive temperature can cause a series of problems, such as the hard core of sponge titanium, increased iron content and increased amount of wall-climbing titanium, all of which seriously affect the final quality of sponge titanium. In order to solve this problem, the present invention provides a new sponge titanium feeding process. Summary of the invention

[0004] The purpose of the present invention is to provide a novel titanium sponge feeding process to solve the problem of excessively high temperature in the middle stage of the reaction mentioned in the above background technology.

[0005] To achieve the above object, the present invention provides a novel titanium sponge feeding process, comprising the following steps:

[0006] S1. Check the air tightness of the reduction furnace and the reactor, and heat up the four heating zones of the reactor from top to bottom to the preset temperature;

[0007] S2. After the temperature is reached, the first feeding stage begins. A titanium tetrachloride feeding pipe and a liquid magnesium feeding pipe are provided on the large cover of the reactor at the same time. The feeding speed is controlled to ensure that the feeding ratio of liquid magnesium is 1.5-2 times that of titanium tetrachloride. The pressure in the reactor is controlled, and magnesium chloride is discharged for a specified number of times during the period.

[0008] S3. After the time reaches the specified value, the second feeding stage begins, and the feeding speed is controlled to ensure that the feeding ratio of liquid magnesium is 1.5-2 times that of titanium tetrachloride, and the pressure in the reactor is controlled, and magnesium chloride is discharged for a specified number of times during the period;

[0009] S4, after the time reaches the specified value, the third feeding stage begins, and the feeding speed is controlled to ensure that the feeding ratio of liquid magnesium is 1.5-2 times that of titanium tetrachloride, and the pressure in the reactor is controlled, and magnesium chloride is discharged for a specified number of times during the period;

[0010] S5. When the amount of titanium tetrachloride added reaches the preset value, the reduction reaction is completed, and the magnesium chloride ladle is prepared for the last discharge of magnesium chloride, and then the heat preservation is carried out to prepare for the distillation section;

[0011] S6. The subsequent distillation and crushing steps are carried out according to conventional operations.

[0012] As a preferred embodiment of the present invention, in step S1, the preset temperatures of the four heating zones are 720-800°C, 720-800°C, 800-900°C and 800-900°C from top to bottom respectively.

[0013] As a preferred embodiment of the present invention, in step S2, the first stage time is 2-10 hours, the titanium tetrachloride feeding rate is 50-100 kg / h, the liquid magnesium feeding rate is 75-200 kg / h, the reactor pressure is controlled at 3-10 kPa, and the magnesium chloride is discharged 2-4 times.

[0014] As a preferred embodiment of the present invention, in step S3, the second stage time is 40-60h, the titanium tetrachloride feeding rate is 300-400kg / h, the liquid magnesium feeding rate is 450-800kg / h, the reactor pressure is controlled at 3-10kPa, and the magnesium chloride is discharged 5-7 times.

[0015] As a preferred embodiment of the present invention, in step S4, the feeding rate of titanium tetrachloride is 80-150 kg / h, the feeding rate of liquid magnesium is 120-300 kg / h, the reactor pressure is controlled at 3-10 kPa, and the magnesium chloride is discharged 2-4 times.

[0016] As a preferred embodiment of the present invention, in step S5, the total amount of titanium tetrachloride added is 20-30 t.

[0017] As a preferred embodiment of the present invention, the reactor is arranged on the inner side of the reaction furnace, the inner wall of the reaction furnace is arranged around the reactor, a group of electric heating tubes are installed inside the four partitions of the reactor, and the control end of the electric heating tube is located inside the reaction furnace.

[0018] As a preferred embodiment of the present invention, the large cover is installed on the top of the reactor through a flange structure, and a titanium tetrachloride feeding pipe and a liquid magnesium feeding pipe are installed on the large cover, and the ends of the titanium tetrachloride feeding pipe and the liquid magnesium feeding pipe extend into the bottom of the reactor.

[0019] As a preferred embodiment of the present invention, a discharge pipe is connected to one side of the bottom of the reactor, and a control valve and a flow meter are installed on the discharge pipe.

[0020] As a preferred embodiment of the present invention, a pressure sensor is installed inside the reactor, a pressure control pipeline is installed on the outer wall of the reactor, and a pressure control valve is installed on the pressure control pipeline.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] 1. The new titanium sponge feeding process effectively solves the problem of excessively high temperature in the middle of the reaction: by adopting the method of adding titanium tetrachloride and liquid magnesium in parallel, the original method of adding all the liquid magnesium into the reactor at once is abandoned, and instead it is added gradually, so that the reactor space is sufficient and the heat dissipation is more sufficient, thereby effectively reducing the temperature in the middle of the reaction, reducing the generation of wall-climbing titanium and hard core, and significantly improving product quality.

[0023] 2. The new titanium sponge feeding process reduces the iron content in the finished titanium sponge product: Since the liquid magnesium is added and utilized gradually, a large amount of liquid magnesium is prevented from being in contact with the reactor for a long time, thereby reducing the dissolution of iron in the liquid magnesium, thereby reducing the iron content in the finished titanium sponge product and improving the purity of the product.

[0024] 3. The new titanium sponge feeding process improves the reaction completeness and reduces the production of low-valent titanium: the parallel flow addition method allows the liquid magnesium to always be present on the surface of the generated titanium sponge lump, effectively avoiding the capillary phenomenon of liquid magnesium in the gaps of the titanium sponge lump, reducing the reaction resistance between liquid magnesium and titanium tetrachloride, making the reaction more complete, thereby reducing the production of low-valent titanium and further improving product quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0026] Figure 2 It is a partial structural schematic diagram of the present invention;

[0027] The meaning of each number in the figure is:

[0028] 1. Reactor; 11. Electric heating tube; 2. Reactor; 3. Large cover; 4. Titanium tetrachloride feeding tube; 5. Liquid magnesium feeding tube; 6. Discharge pipe; 7. Pressure sensor; 8. Pressure control valve. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] Example 1

[0031] The present invention provides a novel titanium sponge feeding process, such as Figure 1-Figure 2 As shown, the reactor 2 is divided into four zones A, B, C, and D from top to bottom, and the steps include:

[0032] S1. After checking the air tightness of the reduction furnace 1 and the reactor 2, the temperature of the A and B zones of the reactor 2 is raised to 720°C, and the temperature of the C and D zones is raised to 800°C;

[0033] S2. After the temperature is reached, the first feeding stage (i.e., the initial stage of the reaction) is started. A titanium tetrachloride feeding pipe 4 and a liquid magnesium feeding pipe 5 are provided on the large cover 3 of the reactor 1. The titanium tetrachloride feeding rate is controlled to be 50 kg / h, the liquid magnesium feeding rate is controlled to be 75 kg / h, and the pressure in the reactor is controlled to be 3 kPa. During this period, magnesium chloride is discharged twice. This stage lasts for 2 hours.

[0034] S3, after the time reaches the specified value, the second feeding stage (i.e., the middle stage of the reaction) is started, the titanium tetrachloride feeding rate is controlled to be 300kg / h, the liquid magnesium feeding rate is controlled to be 450kg / h, the pressure in the reactor 2 is controlled to be 3kPa, and magnesium chloride is discharged 5 times during this period. The time of this stage is 40h;

[0035] S4, after the time reaches the specified value, the third feeding stage (i.e. the end of the reaction) is started, the titanium tetrachloride feeding rate is controlled to be 80kg / h, the liquid magnesium feeding rate is controlled to be 120kg / h, the pressure in the reactor 2 is controlled to be 3kPa, and magnesium chloride is discharged twice during the period;

[0036] S5. When the amount of titanium tetrachloride added reaches 20t, the reduction reaction is completed, and the magnesium chloride ladle is prepared for the last discharge of magnesium chloride, and then the heat preservation is carried out to prepare for the distillation section;

[0037] S6, distillation and crushing steps are carried out according to conventional operations.

[0038] Furthermore, the reactor 2 is arranged on the inner side of the reaction furnace 1, and the inner wall of the reaction furnace 1 is arranged around the reactor 2. A group of electric heating tubes 11 are installed inside the four partitions of the reactor 2, and the control end of the electric heating tube 11 is located inside the reaction furnace 1, which is convenient for independent heating operations of different partitions.

[0039] Furthermore, the large cover 3 is installed on the top of the reactor 2 through a flange structure, and a titanium tetrachloride feeding pipe 4 and a liquid magnesium feeding pipe 5 are installed on the large cover 3. The ends of the titanium tetrachloride feeding pipe 4 and the liquid magnesium feeding pipe 5 extend into the bottom of the reactor 2 to facilitate sufficient feeding operation.

[0040] Furthermore, a discharge pipe 6 is connected to one side of the bottom of the reactor 2, and a control valve and a flow meter are installed on the discharge pipe 6 to facilitate the switching of the discharge and the flow detection.

[0041] Furthermore, a pressure sensor 7 is installed inside the reactor 2, a pressure control pipeline is installed on the outer wall of the reactor 2, and a pressure control valve 8 is installed on the pressure control pipeline for pressure control.

[0042] Example 2

[0043] The present invention provides a novel titanium sponge feeding process, such as Figure 1-Figure 2 As shown, the reactor 2 is divided into four zones A, B, C, and D from top to bottom, and the steps include:

[0044] S1. After checking the air tightness of the reduction furnace 1 and the reactor 2, the temperature of the A and B zones of the reactor 2 is raised to 760°C, and the temperature of the C and D zones is raised to 850°C;

[0045] S2. After the temperature is reached, the first feeding stage (i.e., the initial stage of the reaction) is started. A titanium tetrachloride feeding pipe 4 and a liquid magnesium feeding pipe 5 are provided on the large cover 3 of the reactor 1. The titanium tetrachloride feeding rate is controlled to be 80 kg / h, the liquid magnesium feeding rate is controlled to be 120 kg / h, and the pressure in the reactor is controlled to be 5 kPa. During this period, magnesium chloride is discharged 3 times. This stage lasts for 7 hours.

[0046] S3, after the time reaches the specified value, the second feeding stage (i.e., the middle stage of the reaction) is started, the titanium tetrachloride feeding rate is controlled to be 350kg / h, the liquid magnesium feeding rate is controlled to be 700kg / h, the pressure in the reactor 2 is controlled to be 5kPa, and magnesium chloride is discharged 6 times during this period. The time of this stage is 50h;

[0047] S4, after the time reaches the specified value, the third feeding stage (i.e. the end of the reaction) is started, the titanium tetrachloride feeding rate is controlled to be 100kg / h, the liquid magnesium feeding rate is controlled to be 200kg / h, the pressure in the reactor 2 is controlled to be 5kPa, and magnesium chloride is discharged twice during the period;

[0048] S5. When the amount of titanium tetrachloride added reaches 25t, the reduction reaction is completed, and the magnesium chloride ladle is prepared for the last discharge of magnesium chloride, and then the heat preservation is carried out to prepare for the distillation section;

[0049] S6, distillation and crushing steps are carried out according to conventional operations.

[0050] Furthermore, the reactor 2 is arranged on the inner side of the reaction furnace 1, and the inner wall of the reaction furnace 1 is arranged around the reactor 2. A group of electric heating tubes 11 are installed inside the four partitions of the reactor 2, and the control end of the electric heating tube 11 is located inside the reaction furnace 1, which is convenient for independent heating operations of different partitions.

[0051] Furthermore, the large cover 3 is installed on the top of the reactor 2 through a flange structure, and a titanium tetrachloride feeding pipe 4 and a liquid magnesium feeding pipe 5 are installed on the large cover 3. The ends of the titanium tetrachloride feeding pipe 4 and the liquid magnesium feeding pipe 5 extend into the bottom of the reactor 2 to facilitate sufficient feeding operation.

[0052] Furthermore, a discharge pipe 6 is connected to one side of the bottom of the reactor 2, and a control valve and a flow meter are installed on the discharge pipe 6 to facilitate the switching of the discharge and the flow detection.

[0053] Furthermore, a pressure sensor 7 is installed inside the reactor 2, a pressure control pipeline is installed on the outer wall of the reactor 2, and a pressure control valve 8 is installed on the pressure control pipeline for pressure control.

[0054] Example 3

[0055] The present invention provides a novel titanium sponge feeding process, such as Figure 1-Figure 2 As shown, the reactor 2 is divided into four zones A, B, C, and D from top to bottom, and the steps include:

[0056] S1. After checking the air tightness of the reduction furnace 1 and the reactor 2, the temperature of the A and B zones of the reactor 2 is raised to 800°C, and the temperature of the C and D zones is raised to 900°C;

[0057] S2. After the temperature is reached, the first feeding stage (i.e., the initial stage of the reaction) is started. A titanium tetrachloride feeding pipe 4 and a liquid magnesium feeding pipe 5 are provided on the large cover 3 of the reactor 1. The titanium tetrachloride feeding rate is controlled to be 100 kg / h, the liquid magnesium feeding rate is controlled to be 180 kg / h, and the pressure in the reactor is controlled to be 10 kPa. During this period, magnesium chloride is discharged 3 times. This stage lasts for 10 hours.

[0058] S3, after the time reaches the specified value, the second feeding stage (i.e., the mid-term reaction) is started, the titanium tetrachloride feeding rate is controlled to be 400kg / h, the liquid magnesium feeding rate is controlled to be 650kg / h, the pressure in the reactor 2 is controlled to be 10kPa, and magnesium chloride is discharged 7 times during this period. This stage time is 60h;

[0059] S4, after the time reaches the specified value, the third feeding stage (i.e. the end of the reaction) is started, the titanium tetrachloride feeding rate is controlled to be 150kg / h, the liquid magnesium feeding rate is controlled to be 300kg / h, the pressure in the reactor 2 is controlled to be 10kPa, and magnesium chloride is discharged 4 times during this period;

[0060] S5. When the amount of titanium tetrachloride added reaches 30t, the reduction reaction is completed, and the magnesium chloride ladle is prepared for the last discharge of magnesium chloride, and then the heat preservation is carried out to prepare for the distillation section;

[0061] S6, distillation and crushing steps are carried out according to conventional operations.

[0062] Furthermore, the reactor 2 is arranged on the inner side of the reaction furnace 1, and the inner wall of the reaction furnace 1 is arranged around the reactor 2. A group of electric heating tubes 11 are installed inside the four partitions of the reactor 2, and the control end of the electric heating tube 11 is located inside the reaction furnace 1, which is convenient for independent heating operations of different partitions.

[0063] Furthermore, the large cover 3 is installed on the top of the reactor 2 through a flange structure, and a titanium tetrachloride feeding pipe 4 and a liquid magnesium feeding pipe 5 are installed on the large cover 3. The ends of the titanium tetrachloride feeding pipe 4 and the liquid magnesium feeding pipe 5 extend into the bottom of the reactor 2 to facilitate sufficient feeding operation.

[0064] Furthermore, a discharge pipe 6 is connected to one side of the bottom of the reactor 2, and a control valve and a flow meter are installed on the discharge pipe 6 to facilitate the switching of the discharge and the flow detection.

[0065] Furthermore, a pressure sensor 7 is installed inside the reactor 2, a pressure control pipeline is installed on the outer wall of the reactor 2, and a pressure control valve 8 is installed on the pressure control pipeline for pressure control.

[0066] Comparative Example (Conventional Feeding Process)

[0067] (1) After checking the air tightness of the reduction furnace and reactor, add the specified amount of liquid magnesium, then start the temperature increase program, and heat the reactor A and B zones to 800°C, and C and D zones to 900°C;

[0068] (2) After the temperature is reached, the first feeding stage (i.e., the initial stage of the reaction) is started, the titanium tetrachloride feeding rate is controlled to be 100 kg / h, the pressure in the reactor is controlled to be 10 kPa, and magnesium chloride is discharged 3 times during this period. This stage lasts for 3 hours;

[0069] (3) After the time reaches the specified value, the second feeding stage (i.e., the middle stage of the reaction) begins, the titanium tetrachloride feeding rate is controlled to 400 kg / h, the pressure in the reactor is controlled to 10 kPa, and magnesium chloride is discharged 7 times during this period. This stage lasts for 60 hours;

[0070] (4) After the time reaches the specified value, the third feeding stage (i.e., the final stage of the reaction) begins, the titanium tetrachloride feeding rate is controlled to 150 kg / h, the pressure in the reactor is controlled to 10 kPa, and magnesium chloride is discharged 4 times during this period;

[0071] (5) When the amount of titanium tetrachloride added reaches 30t, the reduction reaction is completed, and the magnesium chloride ladle is prepared for the last discharge of magnesium chloride, and then the heat is kept and prepared for the distillation section;

[0072] (6) The distillation and crushing steps are carried out according to conventional operations.

[0073]

[0074]

[0075] It can be seen from the data in the table that the method provided by the present invention can effectively reduce the generation of wall-climbing titanium and reduce the content of impurity elements.

[0076] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. The above embodiments and descriptions are only preferred examples of the present invention and are not intended to limit the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A novel titanium sponge feeding process, characterized in that: The steps include: S1, checking the air tightness of the reduction furnace (1) and the reactor (2), and heating the four heating zones of the reactor (2) from top to bottom to a preset temperature; S2. After the temperature is reached, the first feeding stage begins. A titanium tetrachloride feeding pipe and a liquid magnesium feeding pipe are provided on the large cover (3) of the reactor (2). The feeding speed is controlled to ensure that the feeding ratio of liquid magnesium is 1.5-2 times that of titanium tetrachloride. The pressure in the reactor (1) is controlled, and magnesium chloride is discharged for a specified number of times during the period. S3, after the time reaches the specified value, the second feeding stage is started, and the feeding speed is controlled to ensure that the feeding ratio of liquid magnesium is 1.5-2 times that of titanium tetrachloride, and the pressure in the reactor (2) is controlled, and magnesium chloride is discharged for a specified number of times during the period; S4, after the time reaches the specified value, the third feeding stage is started, and the feeding speed is controlled to ensure that the feeding ratio of liquid magnesium is 1.5-2 times that of titanium tetrachloride, and the pressure in the reactor (2) is controlled, and magnesium chloride is discharged for a specified number of times during the period; S5. When the amount of titanium tetrachloride added reaches the preset value, the reduction reaction is completed, and the magnesium chloride ladle is prepared for the last discharge of magnesium chloride, and then the heat preservation is carried out to prepare for the distillation section; S6. The subsequent distillation and crushing steps are carried out according to conventional operations.

2. The novel titanium sponge feeding process according to claim 1 is characterized in that: In step S1, the preset temperatures of the four heating zones are 720-800°C, 720-800°C, 800-900°C and 800-900°C from top to bottom respectively.

3. The novel titanium sponge feeding process according to claim 1 is characterized in that: In step S2, the first stage lasts for 2-10 hours, the feeding rate of titanium tetrachloride is 50-100 kg / h, the feeding rate of liquid magnesium is 75-200 kg / h, the pressure of the reactor (2) is controlled at 3-10 kPa, and the magnesium chloride is discharged 2-4 times.

4. The novel titanium sponge feeding process according to claim 1 is characterized in that: In step S3, the second stage time is 40-60h, the titanium tetrachloride feeding rate is 300-400kg / h, the liquid magnesium feeding rate is 450-800kg / h, the pressure of the reactor (2) is controlled at 3-10kPa, and the magnesium chloride is discharged 5-7 times.

5. The novel titanium sponge feeding process according to claim 1 is characterized in that: In step S4, the feeding rate of titanium tetrachloride is 80-150 kg / h, the feeding rate of liquid magnesium is 120-300 kg / h, the pressure of the reactor is controlled at 3-10 kPa, and the magnesium chloride is discharged 2-4 times.

6. The novel titanium sponge feeding process according to claim 1 is characterized in that: In step S5, the total amount of titanium tetrachloride added is 20-30 t.

7. The novel titanium sponge feeding process according to claim 1 is characterized in that: The reactor (2) is arranged on the inner side of the reaction furnace (1), and the inner wall of the reaction furnace (1) is arranged around the reactor (2). A group of electric heating tubes (11) are installed inside the four partitions of the reactor (2), and the control end of the electric heating tube (11) is located inside the reaction furnace (1).

8. The novel titanium sponge feeding process according to claim 1 is characterized in that: The large cover (3) is installed on the top of the reactor (2) through a flange structure. A titanium tetrachloride feeding pipe (4) and a liquid magnesium feeding pipe (5) are installed on the large cover (3). The ends of the titanium tetrachloride feeding pipe (4) and the liquid magnesium feeding pipe (5) extend into the bottom of the reactor (2).

9. The novel titanium sponge feeding process according to claim 1 is characterized in that: A discharge pipe (6) is connected to one side of the bottom of the reactor (2), and a control valve and a flow meter are installed on the discharge pipe (6).

10. The novel titanium sponge feeding process according to claim 1 is characterized in that: A pressure sensor (7) is installed inside the reactor (2), a pressure control pipeline is installed on the outer wall of the reactor (2), and a pressure control valve (8) is installed on the pressure control pipeline.

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