Method for preventing vacuum distillation channel of titanium sponge produced by inverted-U-shaped furnace from being blocked

Abstract

The invention discloses a method for preventing a vacuum distillation channel for producing sponge titanium in an inverted U-shaped furnace from being blocked, which comprises a distillation electric furnace heating step, a low-vacuum distillation step and a high-vacuum distillation step, in the distillation electric furnace heating step, the temperatures of a first area and a second area of a distillation electric furnace are controlled to be 950-980 DEG C, the temperatures of a third area and a fourth area of the distillation electric furnace are controlled to be 900-980 DEG C, and the temperature of a third area and the temperature of a fourth area of the distillation electric furnace are controlled to be 950-980 DEG C; the temperatures of the fifth area and the sixth area of the electric distillation furnace are controlled to be 920-980 DEG C; according to the method, the evaporated Mg and MgCl2 gas can be prevented from being condensed at the condenser channel, and the quality of the sponge titanium is guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of titanium sponge production, in particular to a method for preventing blockage of a vacuum distillation channel of an inverted U-shaped furnace for producing titanium sponge. Background Art

[0002] The magnesium thermal reduction method is used in industry to produce titanium sponge, in which the process of preparing titanium sponge includes two steps: magnesium reduction and vacuum distillation. The vacuum distillation process of titanium sponge is to separate the residual MgCl2, Mg, and inadequately reduced low-valent titanium chloride from the magnesium reduction from the titanium sponge to obtain pure titanium sponge. The separated MgCl2 and Mg enter the condensation tank and solidify into a solid on the tank wall, while the titanium sponge remains in the distillation tank to form a product.

[0003] At present, the production processes adopted by titanium sponge manufacturers include I-type furnace and inverted U-type furnace. Whether it is an I-type furnace or an inverted U-type furnace, a channel pipe is required to connect the distillation tank and the condensation tank during the vacuum distillation stage. During distillation, the residual MgCl2 and Mg in the distillation tank are distilled out under high temperature and high vacuum conditions and enter the condensation tank through the channel pipe. Among them, the I-type furnace is named because the distillation tank and the condensation tank are installed in an I-type during vacuum distillation. In the I-type furnace, the distillation tank and the condensation tank are in an upper and lower structure, and a channel pipe is set in the middle, and a cooling water nozzle is arranged on the condensation tank for forced cooling. When the distillation process conditions are not properly controlled, the distillation channel is very easy to be blocked. After the blockage, the distillation can only be forced to stop. After cooling to room temperature, the high-temperature baffle and condensation tank are replaced, and then the assembly and heating distillation operation are performed again. The blockage of the distillation channel directly affects the smooth distillation production, increases the furnace time and distillation power consumption. At the same time, it will be difficult to separate the impurities in the titanium sponge due to the return to the furnace, and the quality of the titanium sponge will be affected.

[0004] The inverted U-shaped furnace uses an intermediate channel to connect the distillation tank and the condensation tank. The distillation tank and the condensation tank are placed in an inverted "U" shape. The volatile steam enters the condensation tank from the distillation tank and condenses on the inner surface of the condensation tank. The channel pipe as the channel adopts an external heating method to ensure that the evaporated condensate can smoothly pass through the channel into the condensation tank. In the actual production process, when the distillation process is not properly controlled, the steam will condense at the inlet end of the condensation tank and eventually block the channel at the end of the condensation tank. When the channel is blocked, it is necessary to manually dredge the blocked part of the channel, resulting in reduced production efficiency and increased labor intensity. In order to solve the technical problem of channel blockage in the vacuum distillation process of the inverted "U" type furnace, the industry has proposed a method of using a MgCl2 discharge tube as a vacuum tube to regulate the flow direction of Mg and MgCl2 gases, and also proposed a method of regularly dredging the distillation channel by mechanical dredging.

[0005] Chinese patent application CN202410421356.6 discloses a process control method for preventing the distillation channel from being blocked in the production process of titanium sponge in an inverted U-shaped furnace, which mainly includes the following steps: during the reduction feeding process, when the feeding amount reaches 50%-60% of the target total feeding amount, the feeding rate is reduced; when the feeding amount reaches 80%-85% of the target amount, the end point of the reduction feeding is judged according to the pressure relief situation, and the feeding is stopped in time; during the reduction feeding process, when discharging, the liquid level fluctuation in the early and middle stages of the reduction is controlled at 60-70cm, and the liquid level fluctuation in the late and final stages of the reduction is controlled at 30-40cm; after the reduction is completed, it is assembled in sequence according to normal production, and then heated up. In the process control method for preventing the distillation channel from being blocked in the production process of titanium sponge in an inverted U-shaped furnace, the main purpose is to control the magnesium thermal reduction reaction process to prevent secondary reactions and the generation of metal titanium from being blocked in the channel. However, the control effect of the patented method is not good, and there is still a phenomenon that the evaporated Mg and MgCl2 gases condense in the channel at the end of the condenser.

[0006] Therefore, there is an urgent need for a process control method to prevent the distillation channel from being blocked in the sponge titanium production process of an inverted U-shaped furnace. By controlling the process parameters of distillation and condensation and controlling the operating steps, the evaporated Mg and MgCl2 gases can be prevented from condensing in the condenser channel, thereby preventing the channel from being blocked and ensuring the quality of the sponge titanium. Summary of the invention

[0007] The purpose of the present invention is to provide a method for preventing blockage of a vacuum distillation channel in an inverted U-shaped furnace for producing sponge titanium, comprising a distillation furnace temperature control step, a channel temperature control step, a low vacuum distillation step and a high vacuum distillation step, etc., thereby preventing evaporated Mg and MgCl2 gases from condensing in the condenser channel, preventing blockage of the channel and ensuring the quality of sponge titanium.

[0008] In order to achieve the purpose of the above invention, the present invention provides a method for preventing blockage of a vacuum distillation channel of an inverted U-shaped furnace for producing sponge titanium, comprising a distillation furnace heating step, a low vacuum distillation step and a high vacuum distillation step, in which the temperature of zones 1 and 2 of the distillation furnace is controlled at 950°C-980°C, the temperature of zones 3 and 4 of the distillation furnace is controlled at 900°C-980°C, and the temperature of zones 5 and 6 of the distillation furnace is controlled at 920°C-980°C; wherein the bottom of the distillation furnace is set as a reference plane, the temperature measuring point of zone 1 of the distillation furnace is 5.5±0.5 meters away from the reference plane, the temperature measuring point of zone 2 is 4.5±0.5 meters away from the reference plane, the temperature measuring point of zone 3 is 3.5±0.5 meters away from the reference plane, the temperature measuring point of zone 4 is 2.5±0.2 meters away from the reference plane, the temperature measuring point of zone 5 is 1.5±0.2 meters away from the reference plane, and the temperature measuring point of zone 6 is 0.5±0.1 meter away from the bottom.

[0009] According to the method for preventing blockage of the vacuum distillation channel of an inverted U-shaped furnace for producing sponge titanium, preferably, in the distillation electric furnace heating step, the temperatures of points 1 and 2 of the channel are controlled at 850°C to 880°C, and the temperature of point 3 of the channel is 850°C to 900°C; wherein, the temperature measuring point at point 1 of the channel is located at the beginning of the channel pipe, the temperature measuring point at point 2 is located in the middle of the channel pipe, and the temperature measuring point at point 3 is located at the end of the channel pipe.

[0010] According to the method for preventing blockage of the vacuum distillation channel of an inverted U-shaped furnace for producing sponge titanium, preferably, in the low vacuum distillation step, the duration of the low vacuum distillation is 20h to 30h; wherein the vacuum pressure of the vacuum unit of the low vacuum distillation is >20Pa.

[0011] According to a method for preventing blockage of a vacuum distillation channel in an inverted U-shaped furnace for producing sponge titanium according to the present invention, preferably, in the low vacuum distillation step, when the detected temperature in the condensation tank is ≤420°C or the low vacuum duration is >30h, the high vacuum distillation step is started; wherein the vacuum pressure of the vacuum unit of the high vacuum distillation is ≤20Pa.

[0012] According to the method for preventing blockage of the vacuum distillation channel of an inverted U-shaped furnace for producing sponge titanium according to the present invention, preferably, in the high vacuum distillation step, within 0 to 30 hours of the high vacuum distillation, the opening of the water inlet valve of the cooling water jacket is controlled to be 35% to 50%.

[0013] According to the method for preventing blockage of the vacuum distillation channel of an inverted U-shaped furnace for producing sponge titanium, preferably, in the high vacuum distillation step, when the detected temperature in the condenser is lower than 300°C, the opening of the water inlet valve of the cooling water jacket is adjusted to 20% to 30%.

[0014] According to the method for preventing blockage of the vacuum distillation channel of an inverted U-shaped furnace for producing sponge titanium according to the present invention, preferably, in the high vacuum distillation step, within 30 to 90 hours of high vacuum distillation, the opening of the water inlet valve of the cooling water jacket is controlled to be 20% to 30%.

[0015] According to the method for preventing blockage of the vacuum distillation channel of an inverted U-shaped furnace for producing sponge titanium, preferably, in the high vacuum distillation step, when the detected temperature in the condensation tank is lower than 250°C, the opening of the water inlet valve of the cooling water jacket is adjusted to 10% to 20%.

[0016] According to the method for preventing the blockage of the vacuum distillation channel of the inverted U-shaped furnace for producing sponge titanium, preferably, it also includes a channel blockage judgment step: during the process from the beginning of distillation in the distillation tank to 120 hours of distillation, the system pressure drops to below 1Pa and shows a continuous downward trend; at the same time, when the pressure of the distillation tank continues to rise and the detected temperature in the condenser continues to decrease, it is judged that blockage occurs; wherein, the temperature monitoring point of the system pressure is set on the connecting pipeline between the outlet of the condenser and the outlet of the vacuum unit.

[0017] According to the method for preventing blockage of the vacuum distillation channel of an inverted U-shaped furnace for producing sponge titanium, preferably, in the channel blockage judgment step, during the process from the beginning of distillation in the distillation tank to 120 hours of distillation, when the detected temperature of the condensing tank drops below 200°C and the rate of decrease of the detected temperature of the condensing tank is greater than 30°C / h, it is judged that blockage occurs.

[0018] The beneficial effects of the present invention are: The present invention provides a method for preventing blockage of a vacuum distillation channel in an inverted U-shaped furnace for producing sponge titanium, comprising a distillation furnace temperature control step, a channel temperature control step, a low vacuum distillation step, and a high vacuum distillation step, thereby preventing evaporated Mg and MgCl2 gases from condensing at the condenser channel and blocking the channel, while ensuring the quality of the sponge titanium. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other embodiments can be obtained based on these drawings without paying creative work.

[0020] Figure 1 The present invention is a schematic diagram of the device structure of a method for preventing the blockage of a vacuum distillation channel of an inverted U-shaped furnace for producing sponge titanium.

[0021] Among them, 1-distillation tank, 2-distillation furnace, 3-feeding inlet, 4-condensation tank, 5-cooling water jacket, 6-vacuum unit, 7-cooling water jacket, 8-external heater, 10-connecting pipeline. DETAILED DESCRIPTION

[0022] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the embodiments of the present invention are further described in detail below in combination with specific embodiments and with reference to the accompanying drawings.

[0023] Currently, if Figure 1The inverted U-shaped furnace includes a distillation tank 1 and a condensation tank 4, which are connected by a channel pipe 7 in the middle. The distillation tank is heated by a distillation electric furnace 2. The distillation tank 1 and the condensation tank 4 are placed in an inverted "U" shape. The volatile steam enters the condensation tank 4 from the distillation tank 1 through the channel pipe 7. The outside of the condensation tank 4 is provided with a cooling water jacket 5 to cool the condensation tank 4, and condensation occurs on the inner surface of the condensation tank 4. The cooling water jacket 7 uses an external heater 8 to ensure that the evaporated condensate can smoothly pass through the channel into the condensation tank 4. The distillation tank 4 is fed with TiCl4 through the feeding inlet 3.

[0024] In the prior art, in order to control the flow direction of Mg and MgCl2 gases, a vacuum unit is added to evacuate the condenser system, and the inlet of the vacuum unit is connected to the outlet of the condenser 4 through a pipe 10 to solve the technical problem of channel blockage during the vacuum distillation process of the inverted "U" furnace. Among them, the temperature detection point of the condenser 4 is detected by a temperature sensor inserted into the tank body; the system pressure detection point is set on the connecting pipe 10 between the outlet of the condenser and the inlet of the vacuum unit.

[0025] The present invention provides a method for preventing the blockage of a vacuum distillation channel in an inverted U-shaped furnace for producing sponge titanium, comprising a distillation electric furnace heating step, a low vacuum distillation step and a high vacuum distillation step. A more preferred technical solution is that the method of the present invention also includes a channel blockage judgment step.

[0026] The distillation electric furnace heating step includes: in the distillation electric furnace heating step, the temperature of zones 1 and 2 of the distillation electric furnace is controlled at 950°C ~ 980°C, the temperature of zones 3 and 4 of the distillation electric furnace is controlled at 900°C ~ 980°C, and the temperature of zones 5 and 6 of the distillation electric furnace is controlled at 920°C ~ 980°C; wherein, the furnace bottom of the distillation electric furnace is set as a reference plane, the temperature measuring point of zone 1 of the distillation electric furnace is 5.5±0.5 meters away from the reference plane, the temperature measuring point of zone 2 is 4.5±0.5 meters away from the reference plane, the temperature measuring point of zone 3 is 3.5±0.5 meters away from the reference plane, the temperature measuring point of zone 4 is 2.5±0.2 meters away from the reference plane, the temperature measuring point of zone 5 is 1.5±0.2 meters away from the reference plane, and the temperature measuring point of zone 6 is 0.5±0.1 meter away from the bottom.

[0027] The low vacuum distillation step also includes: in the distillation electric furnace heating step, the temperature of points 1 and 2 of the channel is controlled at 850℃~880℃, and the temperature of point 3 of the channel is 850℃~900℃; wherein, the temperature measuring point of point 1 of the channel is located at the beginning of the channel pipe, the temperature measuring point of point 2 is located in the middle of the channel pipe, and the temperature measuring point of point 3 is located at the end of the channel pipe.

[0028] The low vacuum distillation step includes: the duration of the low vacuum distillation is 20h to 30h; wherein, the vacuum pressure of the vacuum unit of the low vacuum distillation is greater than 20Pa; preferably, in the low vacuum distillation step, when the detected temperature in the condensation tank is ≤420°C or the low vacuum duration is greater than 30h, the high vacuum distillation step is started; wherein, the vacuum pressure of the vacuum unit of the high vacuum distillation is ≤20Pa.

[0029] The high vacuum distillation step includes: within 0 to 30 hours of high vacuum distillation, controlling the opening of the water inlet valve of the cooling water jacket to be 35% to 50%; preferably, when the detected temperature in the condenser is lower than 300°C, adjusting the opening of the water inlet valve of the cooling water jacket to 20% to 30%; more preferably, within 30 to 90 hours of high vacuum distillation, controlling the opening of the water inlet valve of the cooling water jacket to be 20% to 30%.

[0030] As a specific embodiment of the present invention, in the high vacuum distillation step, when the detected temperature in the condenser is lower than 250° C., the opening of the water inlet valve of the cooling water jacket is adjusted to 10% to 20%.

[0031] Regarding the channel blockage judgment step: during the process from the start of distillation in the distillation tank to 120 hours of distillation, the system pressure drops to below 1Pa and shows a continuous downward trend; at the same time, the pressure in the distillation tank continues to rise, and the detected temperature in the condenser continues to drop; wherein, the temperature monitoring point of the system pressure is arranged on the connecting pipeline between the outlet of the condenser and the outlet of the vacuum unit; preferably, in the channel blockage judgment step, during the process from the start of distillation in the distillation tank to 120 hours of distillation, when the detected temperature of the condenser drops to below 200°C, the detected temperature drop rate of the condenser is greater than 30°C / h.

[0032] Example 1 This embodiment provides a method for preventing blockage of a vacuum distillation channel of an inverted U-shaped furnace for producing titanium sponge, which specifically comprises the following steps: (1) Assembling the channel pipe 7 of the inverted U-shaped furnace that has undergone the pressure control test with the external heater 8; (2) Control the temperature of zones 1 and 2 of the distillation furnace 2 at 950°C, the temperature of zones 3 and 4 of the distillation furnace 2 at 900°C, and the temperature of zones 5 and 6 of the distillation furnace 2 at 920°C; control the temperature of points 1 and 2 of the channel pipe 7 at 850°C, and the temperature of point 3 of the channel pipe 7 at 880°C.

[0033] (3) First, start the vacuum pump 6 to perform low vacuum distillation operation. The low vacuum distillation lasts for 22 hours. The detected temperature of the condenser 4 drops to 410°C. At this time, adjust the vacuum degree of the vacuum pump 6 to start the high vacuum distillation operation.

[0034] (4) After the high vacuum distillation is started, the water inlet valve opening of the cooling water jacket 5 is controlled to be 40% in the first 30 hours; from 30 hours to 90 hours, the water inlet valve opening of the cooling water jacket 5 is controlled to be 25%; and this is continued until the vacuum distillation is completed.

[0035] The entire vacuum distillation stage of producing titanium sponge in the inverted U-shaped furnace went smoothly, and there was no channel blockage problem. The produced titanium sponge did not exceed the chlorine impurity standard. The content of chlorine impurities in the titanium sponge was 0.038%, meeting the national standard product quality requirements.

[0036] Example 2 This embodiment provides a method for preventing blockage of a vacuum distillation channel of an inverted U-shaped furnace for producing titanium sponge, which specifically comprises the following steps: (1) Assembling the channel pipe 7 of the inverted U-shaped furnace that has undergone the pressure control test with the external heater 8; (2) Control the temperature of zones 1 and 2 of the distillation furnace 2 at 960°C, the temperature of zones 3 and 4 of the distillation furnace 2 at 950°C, and the temperature of zones 5 and 6 of the distillation furnace 2 at 960°C; control the temperature of points 1 and 2 of the channel pipe 7 at 860°C, and the temperature of point 3 of the channel pipe 7 at 880°C.

[0037] (3) First, start the vacuum pump 6 to perform low vacuum distillation. The low vacuum distillation lasts for 30 hours. The detected temperature of the condenser 4 drops to 430°C. At this time, adjust the vacuum degree of the vacuum pump 6 to perform high vacuum distillation operation.

[0038] (4) After the high vacuum distillation is started, the water inlet valve opening of the cooling water jacket 5 is controlled to be 45% in the first 30 hours; from 30 hours to 70 hours, the water inlet valve opening of the cooling water jacket 5 is controlled to be 20%; when the measured temperature of the condenser 4 is 240°C, adjust the water inlet valve opening of the cooling water jacket 5 to 15% and continue until the end of the vacuum distillation.

[0039] The entire vacuum distillation stage of producing titanium sponge in the inverted U-shaped furnace went smoothly, and there was no channel blockage problem. The produced titanium sponge did not exceed the chlorine impurity standard. The content of chlorine impurities in the titanium sponge was 0.042%, meeting the national standard product quality requirements.

[0040] Example 3 This embodiment provides a method for preventing blockage of a vacuum distillation channel of an inverted U-shaped furnace for producing titanium sponge, which specifically comprises the following steps: (1) Assemble the channel pipe of the inverted U-shaped furnace that has passed the pressure control test with an external heater; (2) Control the temperature of zones 1 and 2 of the distillation furnace 2 at 900°C, the temperature of zones 3 and 4 of the distillation furnace 2 at 930°C, and the temperature of zones 5 and 6 of the distillation furnace 2 at 920°C; control the temperature of points 1 and 2 of the channel pipe 7 at 850°C, and the temperature of point 3 of the channel pipe 7 at 850°C.

[0041] (3) First, start the vacuum pump 6 to start low vacuum distillation. The low vacuum distillation lasts for 30 hours. When the temperature detected in the condenser 4 drops to 430°C, adjust the vacuum degree of the vacuum pump 6 to perform high vacuum distillation operation.

[0042] (4) After the high vacuum distillation is started, the water inlet valve opening of the cooling water jacket 5 is controlled at 45% in the first 30 hours; from 30 hours to 60 hours, the water inlet valve opening of the cooling water jacket 5 is controlled at 30%; when the measured temperature of the condenser 4 is 200°C, the water inlet valve opening of the cooling water jacket 5 is adjusted down to 15%; from 60 hours to 80 hours, when the detected temperature drop rate of the condenser 4 reaches 35°C / h, it is judged that the channel is blocked, and the blocked part is manually cleaned, and the process parameters are fine-tuned until the end of the vacuum distillation.

[0043] The produced titanium sponge has relatively high chlorine impurities, with a content of 0.064% in the titanium sponge, which does not meet the quality requirements of grade 0 in the national standard products.

[0044] A person skilled in the art should understand that the discussion of any of the above embodiments is only exemplary and is not intended to imply that the scope of the disclosure of the embodiments of the present invention (including the claims) is limited to these examples; under the concept of the embodiments of the present invention, the technical features in the above embodiments or different embodiments can also be combined, and there are many other changes in different aspects of the embodiments of the present invention as described above, which are not provided in detail for the sake of simplicity. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the embodiments of the present invention should be included in the protection scope of the embodiments of the present invention.

Claims

1. A method for preventing blockage of a vacuum distillation channel in an inverted U-shaped furnace for producing sponge titanium, comprising a distillation electric furnace heating step, a low vacuum distillation step and a high vacuum distillation step, characterized in that: In the distillation furnace heating step, the temperature of the distillation furnace zones 1 and 2 is controlled at 950°C to 980°C, the temperature of the distillation furnace zones 3 and 4 is controlled at 900°C to 980°C, and the temperature of the distillation furnace zones 5 and 6 is controlled at 920°C to 980°C; wherein, The bottom of the distillation electric furnace is set as the reference plane. The temperature measuring point in zone 1 of the distillation electric furnace is 5.5±0.5 meters away from the reference plane, the temperature measuring point in zone 2 is 4.5±0.5 meters away from the reference plane, the temperature measuring point in zone 3 is 3.5±0.5 meters away from the reference plane, the temperature measuring point in zone 4 is 2.5±0.2 meters away from the reference plane, the temperature measuring point in zone 5 is 1.5±0.2 meters away from the reference plane, and the temperature measuring point in zone 6 is 0.5±0.1 meter away from the bottom.

2. A method for preventing blockage of a vacuum distillation channel in an inverted U-shaped furnace for producing titanium sponge according to claim 1, characterized in that: In the distillation furnace heating step, the temperature of channel 1 and 2 is controlled at 850°C to 880°C, and the temperature of channel 3 is controlled at 850°C to 900°C; wherein, The temperature measuring point at point 1 of the channel is located at the beginning of the channel pipe, the temperature measuring point at point 2 is located in the middle of the channel pipe, and the temperature measuring point at point 3 is located at the end of the channel pipe.

3. A method for preventing blockage of a vacuum distillation channel in an inverted U-shaped furnace for producing titanium sponge according to claim 2, characterized in that: In the low vacuum distillation step, the duration of the low vacuum distillation is 20h to 30h; wherein, The vacuum pressure of the vacuum unit for low vacuum distillation is >20Pa.

4. A method for preventing blockage of a vacuum distillation channel in an inverted U-shaped furnace for producing titanium sponge according to claim 3, characterized in that: In the low vacuum distillation step, when the detected temperature in the condenser is ≤420°C or the low vacuum duration is >30h, the high vacuum distillation step is started; wherein, The vacuum pressure of the vacuum unit for high vacuum distillation is ≤20Pa.

5. The method for preventing blockage of the vacuum distillation channel of an inverted U-shaped furnace for producing titanium sponge according to claim 1, characterized in that: In the high vacuum distillation step, within 0 to 30 hours of high vacuum distillation, the opening of the water inlet valve of the cooling water jacket is controlled to be 35% to 50%.

6. A method for preventing blockage of a vacuum distillation channel in an inverted U-shaped furnace for producing titanium sponge according to claim 5, characterized in that: In the high vacuum distillation step, when the detected temperature in the condenser is lower than 300°C, adjust the opening of the water inlet valve of the cooling water jacket to 20% to 30%.

7. The method for preventing blockage of a vacuum distillation channel in an inverted U-shaped furnace for producing titanium sponge according to claim 1, characterized in that: In the high vacuum distillation step, within 30 to 90 hours of high vacuum distillation, the opening of the water inlet valve of the cooling water jacket is controlled to be 20% to 30%.

8. A method for preventing blockage of a vacuum distillation channel in an inverted U-shaped furnace for producing titanium sponge according to claim 7, characterized in that: In the high vacuum distillation step, when the detected temperature in the condenser is lower than 250°C, adjust the opening of the water inlet valve of the cooling water jacket to 10% to 20%.

9. The method for preventing blockage of a vacuum distillation channel in an inverted U-shaped furnace for producing titanium sponge according to claim 1, characterized in that: It also includes a channel blockage judgment step: during the process from the beginning of distillation in the distillation tank to 120 hours of distillation, the system pressure drops below 1Pa and shows a continuous downward trend; at the same time, the pressure in the distillation tank continues to rise, and the detection temperature in the condensation tank continues to drop, judging that blockage occurs; wherein, The temperature monitoring point of the system pressure is set on the connecting pipeline between the condenser outlet and the vacuum unit outlet.

10. A method for preventing blockage of a vacuum distillation channel in an inverted U-shaped furnace for producing titanium sponge according to claim 9, characterized in that: In the channel blockage judgment step, during the process from the beginning of distillation in the distillation tank to 120 hours of distillation, when the detected temperature of the condensation tank drops below 200°C and the rate of decrease of the detected temperature of the condensation tank is greater than 30°C / h, it is judged that blockage occurs.

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