Method and system for recovering titanium tetrachloride from titanium tetrachloride slurry

Abstract

The invention provides a method for recovering titanium tetrachloride from titanium tetrachloride slurry. The invention also provides a system for recovering titanium tetrachloride from titanium tetrachloride slurry. The atomization device and the titanium tetrachloride gas storage device are additionally arranged in an existing titanium tetrachloride slurry evaporation system, waste heat of high-temperature titanium tetrachloride gas is used for conducting heat exchange drying on atomized titanium tetrachloride slurry, and the waste heat of the high-temperature titanium tetrachloride is combined with the efficient drying efficiency of atomization drying; the energy of titanium tetrachloride can be fully utilized, the burden of the system is reduced, the system is optimized, the treatment capacity of titanium tetrachloride slurry is increased, and the recovery efficiency and recovery rate of titanium tetrachloride are improved. The method provided by the invention is beneficial to smooth operation of the whole chlorination refining system, and the obtained titanium tetrachloride product is stable in quality.

Description

Technical Field

[0001] The present invention relates to the technical field of titanium tetrachloride production, and in particular to a method for recovering titanium tetrachloride from titanium tetrachloride slurry. The present invention also relates to a system for recovering titanium tetrachloride from titanium tetrachloride slurry. Background Art

[0002] Titanium products are widely used in various important fields such as aerospace, aviation, vehicle engineering, coatings, inks, biomedical engineering, etc. Titanium tetrachloride is a colorless and transparent liquid with a pungent odor at room temperature. It is an intermediate product in the production process of titanium and its compounds and an important raw material for titanium industry production. Titanium tetrachloride is mainly used to produce sponge titanium, chloride titanium dioxide, pearlescent dyes, solvents, nano-titanium dioxide, titanate functional ceramics, ultrafine titanium dioxide, titanate coupling agent, mica titanium pearlescent pigments, and catalysts for polyethylene and polypropylene. It can also be widely used in many fields such as chemical industry, electronics, agriculture and military.

[0003] The methods for preparing titanium tetrachloride are generally molten salt chlorination and boiling chlorination. The characteristics of both methods are to mix high-titanium slag with petroleum coke and then react with chlorine gas for chlorination. Molten salt chlorination can treat low-grade high-calcium and high-magnesium titanium slag. It is widely used in China, especially in Panxi area. The crude titanium tetrachloride produced by the chlorination furnace has many impurities after leaving the furnace, including high-boiling point impurities FeCl3, AlCl3, MgCl2 and low-boiling point impurities VOCl3, SiCl4, as well as some soluble gas impurities such as Cl2, HCl and O2. The process of removing impurities by heating, distillation, condensation, adsorption and chemical reaction to obtain refined titanium tetrachloride is called titanium tetrachloride refining process.

[0004] However, some crude titanium tetrachloride is attached with small solid particles that cannot be effectively separated from the solid and liquid, forming titanium tetrachloride slurry that cannot be effectively utilized. Some companies return the titanium tetrachloride slurry to the chlorination furnace to recover titanium tetrachloride, but for slurry with high solid content, long-term operation will cause fine particles in the system to never be discharged from the system, which will cause a series of blockages, quality deterioration and other problems. The mud evaporation method combined with the return of mud to the furnace is a method that is widely used in existing production by enterprises. The mud evaporation method heats the mud in the evaporation device to evaporate and gasify it, and then condenses and recovers the titanium tetrachloride liquid. This method has strict requirements on the evaporation temperature control, and it is easy to overheat and sublimate other chlorinated impurities into the tail gas system, thereby clogging the system. In addition, the amount of mud entering the furnace is affected by the volume of the mud itself, and the evaporation recovery efficiency is low.

[0005] Therefore, the prior art still has much room for improvement in treating titanium tetrachloride slurry to recover titanium tetrachloride. Summary of the invention

[0006] In view of the shortcomings of the prior art, the present invention aims to provide a method for recovering titanium tetrachloride from titanium tetrachloride slurry. The present invention also provides a system for recovering titanium tetrachloride from titanium tetrachloride slurry.

[0007] In order to achieve the above object, the present invention adopts the following technical solutions: The present invention provides a method for recovering titanium tetrachloride from titanium tetrachloride slurry, comprising the following steps: S10, transporting the first titanium tetrachloride slurry to an evaporation device for evaporation treatment to obtain a first titanium tetrachloride gas; S20, transporting the first titanium tetrachloride gas to a gas storage device; S30, atomizing the second titanium tetrachloride slurry to obtain an atomized second titanium tetrachloride slurry; S40, using the first titanium tetrachloride gas obtained in step S20 to dry the atomized second titanium tetrachloride slurry obtained in step S30, to obtain the dried second titanium tetrachloride slurry and the first titanium tetrachloride gas after heat exchange; S50, condensing the first titanium tetrachloride gas obtained after heat exchange in step S40 to obtain crude titanium tetrachloride; S60, transporting the dried second titanium tetrachloride slurry obtained in step S40 to an evaporation device for evaporation treatment to obtain a second titanium tetrachloride gas, and performing a slag discharge treatment on the evaporation device; S70, repeat the above steps.

[0008] In one embodiment, in step S10, the concentration of the first titanium tetrachloride slurry is 50 g / ml to 300 g / ml.

[0009] In one embodiment, in step S10, the evaporation temperature is 200°C to 500°C, and the heating time is 2h to 10h.

[0010] In one embodiment, in step S20, when the pressure of the gas storage device rises to 30 MPa to 150 MPa, the first titanium tetrachloride gas is stopped from being delivered to the gas storage device.

[0011] In one embodiment, in step S40, the concentration of the dried second titanium tetrachloride slurry is 300 g / ml to 500 g / ml.

[0012] In one embodiment, in step S60, when the material level of the conveyed dried second titanium tetrachloride slurry in the evaporation device reaches 50% to 80% of the maximum material level of the evaporation device, the second titanium tetrachloride gas is conveyed to the gas storage device, and then the evaporation device is deslagging.

[0013] In one embodiment, before step S20, a step of removing dust from the first titanium tetrachloride gas is further included.

[0014] In one embodiment, before step S50, a step of removing dust from the first titanium tetrachloride gas after heat exchange is further included.

[0015] The present invention also provides a system for recovering titanium tetrachloride from titanium tetrachloride slurry, the system comprising: An evaporation device, the evaporation device comprising a first slurry inlet for introducing a first titanium tetrachloride slurry, a second slurry inlet for introducing a dried second titanium tetrachloride slurry, a gas outlet for the evaporation device, and a slag outlet for the evaporation device; A gas storage device, the gas storage device comprising a gas storage device inlet and a gas storage device outlet, the gas storage device inlet is connected to the gas outlet of the evaporation device, and the gas storage device is used to store titanium tetrachloride gas; an atomizing device, wherein the atomizing device comprises an atomizing device mud inlet and an atomizing device mud outlet, and the second titanium tetrachloride slurry enters the atomizing device through the atomizing device mud inlet; a heat exchange device, the heat exchange device comprising a heat exchange device mud inlet, a heat exchange device mud outlet, a heat exchange device gas inlet and a heat exchange device gas outlet, the heat exchange device mud inlet is connected to the atomization device mud outlet, the heat exchange device mud outlet is connected to the evaporation device second mud inlet, and the heat exchange device gas inlet is connected to the gas storage device outlet; and A condensing device, wherein the condensing device comprises a condensing device inlet and a condensing device outlet, wherein the condensing device inlet is communicated with the gas outlet of the heat exchange device, and the condensing device outlet is communicated with the crude titanium tetrachloride storage device.

[0016] In one embodiment, the system further comprises: a first dust removal device, the first dust removal device comprising a first dust removal device inlet and a first dust removal device outlet, the first dust removal device inlet is connected to the evaporation device gas outlet, and the first dust removal device outlet is connected to the gas storage device inlet; a second dust removal device, the second dust removal device comprising a second dust removal device inlet and a second dust removal device outlet, the second dust removal device inlet is connected to the gas outlet of the heat exchange device, and the second dust removal device outlet is connected to the condensing device inlet; and A slag storage device is connected to a slag discharge port of the evaporation device.

[0017] Compared with the prior art, the beneficial technical effects of the present invention are: The method of the present invention solves the technical problems of low titanium tetrachloride sludge recovery rate, difficult process control, high equipment requirements and low production efficiency in the prior art by adopting the method of "mud evaporation method + utilization of titanium tetrachloride waste heat + atomization drying method".

[0018] The present invention adds an atomizing device and a titanium tetrachloride gas storage device to the existing titanium tetrachloride slurry evaporation system, utilizes the waste heat of the high-temperature titanium tetrachloride gas itself to heat exchange and dry the atomized titanium tetrachloride slurry, combines the waste heat of the high-temperature titanium tetrachloride with the efficient drying efficiency of the atomization drying, can fully utilize the energy of titanium tetrachloride, reduce the system burden, optimize the system, increase the titanium tetrachloride slurry processing capacity, and improve the titanium tetrachloride recovery efficiency and recovery rate. The method of the present invention is conducive to the smooth operation of the entire chlorination refining system, and the quality of the titanium tetrachloride product obtained is stable. In addition, the present invention does not perform pretreatment operations such as vanadium removal on the titanium tetrachloride slurry, saving costs. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0020] Figure 1 A schematic flow chart of a method for recovering titanium tetrachloride from titanium tetrachloride slurry according to the present invention; Figure 2 The figure is a schematic structural diagram of a system for recovering titanium tetrachloride from titanium tetrachloride slurry according to the present invention. DETAILED DESCRIPTION

[0021] The following is a further detailed description of the embodiments of the present disclosure in conjunction with the accompanying drawings and examples. The detailed description of the following embodiments and the accompanying drawings are used to exemplarily illustrate the principles of the present disclosure, but cannot be used to limit the scope of the present disclosure. The present disclosure can be implemented in many different forms and is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

[0022] The present disclosure provides these embodiments to make the present disclosure thorough and complete, and to fully express the scope of the present disclosure to those skilled in the art. It should be noted that unless otherwise specifically stated, the relative arrangement of the parts and steps, the composition of the materials, the numerical expressions and the numerical values ​​set forth in these embodiments should be interpreted as being merely exemplary, and not as limiting.

[0023] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0024] The terms "including" and "having" and any variations thereof in the specification and claims of the present invention and the above-mentioned drawings are intended to cover non-exclusive inclusions; the terms "first", "second", etc. in the specification and claims of the present disclosure or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order. "Multiple" means two or more, unless otherwise clearly and specifically limited.

[0025] It should be understood by those skilled in the art that the temperature of the titanium tetrachloride slurry in the evaporation device can reach about 300°C, while the condensation point of titanium tetrachloride gas is about 135°C. If the temperature control in the evaporation device is not fine enough, the temperature of the titanium tetrachloride gas in the evaporation device will be too high, and the pressure of the condensation system will be large, and the condensation efficiency will be low. At the same time, due to the large volume of titanium tetrachloride slurry, the processing capacity of the evaporation device is not high enough. Spray drying has a unique advantage in drying speed. Therefore, combining the atomization device to treat the titanium tetrachloride slurry can solve the technical problem of insufficient titanium tetrachloride processing capacity when using a single evaporation device for processing.

[0026] like Figure 1 As shown, the present invention provides a method for recovering titanium tetrachloride from titanium tetrachloride slurry, the method comprising the following steps: S10, transporting the first titanium tetrachloride slurry to the evaporation device 100 for evaporation treatment to obtain a first titanium tetrachloride gas.

[0027] S20, transporting the first titanium tetrachloride gas to the gas storage device 200.

[0028] S30, atomizing the second titanium tetrachloride slurry to obtain an atomized second titanium tetrachloride slurry.

[0029] S40, using the first titanium tetrachloride gas obtained in step S20 to dry the atomized second titanium tetrachloride slurry obtained in step S30, to obtain the dried second titanium tetrachloride slurry and the first titanium tetrachloride gas after heat exchange.

[0030] S50, condensing the first titanium tetrachloride gas obtained after heat exchange in step S40 to obtain crude titanium tetrachloride.

[0031] S60, transporting the dried second titanium tetrachloride slurry obtained in step S40 to the evaporation device 100 for evaporation treatment to obtain second titanium tetrachloride gas, and performing slag discharge treatment on the evaporation device.

[0032] S70, repeat the above steps.

[0033] In one embodiment, in step S10, the concentration of the first titanium tetrachloride slurry is 50 g / ml to 300 g / ml. A first titanium tetrachloride slurry with too low a concentration will result in low evaporation efficiency of titanium tetrachloride, and a first titanium tetrachloride slurry with too high a concentration will have a greater impact on the smooth operation of the entire system, for example, the probability of blockage is greatly increased. The concentration of the first titanium tetrachloride slurry of the present invention comprehensively considers the evaporation efficiency and the smoothness of the system operation.

[0034] In one embodiment, in step S10, the evaporation temperature is 200°C to 500°C, and the heating time is 2h to 10h. When the evaporation temperature is lower than 200°C, the gasification effect of titanium tetrachloride in the evaporation device 100 is poor, and the heating time is prolonged. When the evaporation temperature is higher than 500°C, the cooling pressure of the system increases, and the smoke and dust carried away by the hot air flow that heats up too quickly is not conducive to the stable operation of the dust removal device.

[0035] In one embodiment, in step S20, when the pressure of the gas storage device 200 rises to 30MPa-150MPa, the first titanium tetrachloride gas is stopped from being delivered to the gas storage device 200. The heating time in step S10 is related to the pressure of the gas storage device 200. The pressure of the gas storage device 200 is set to 30MPa-150MPa so that the pressure of the gas storage device 200 is raised to ensure that the first titanium tetrachloride gas stored in the gas storage device 200 can smoothly enter the heat exchange device 400 for heat exchange treatment, and at the same time, there will be no situation of causing a large load on the system. The premise of increasing the pressure of the gas storage device 200 is to heat the evaporation device 100 to generate the first titanium tetrachloride gas so that it enters the gas storage device 200. Setting a certain heating time is conducive to process control.

[0036] In one embodiment, in step S40, the concentration of the dried second titanium tetrachloride slurry is 300 g / ml to 500 g / ml. Due to the high efficiency of the atomization drying process, an excessively high concentration of the second titanium tetrachloride slurry will lead to a reduction in the evaporable liquid in the evaporation device 100, affecting the continuous operation of the gas storage device 200 and the system cycle.

[0037] In one embodiment, in step S60, when the material level of the transported dried second titanium tetrachloride slurry in the evaporation device 100 reaches 50% to 80% of the maximum material level of the evaporation device 100, the second titanium tetrachloride gas is transported to the gas storage device 200, and then the evaporation device 100 is deslagging. During the entire evaporation process, the pressure of the gas storage device 200 is constantly changing, which depends on the pressure control of the entire system. When the system continues to operate, the volume of the entire titanium tetrachloride slurry rises dynamically, and the titanium tetrachloride in the titanium tetrachloride slurry is continuously recycled into the gas storage device 200. 50% to 80% of the maximum material level of the evaporation device 100 is used as a signal to replenish titanium tetrachloride gas to the gas storage device 200 and to deslagging the evaporation device 100, so as to ensure stable operation of the system.

[0038] In one embodiment, before step S20, the first titanium tetrachloride gas is further subjected to dust removal. In one embodiment, before step S50, the first titanium tetrachloride gas after heat exchange is further subjected to dust removal.

[0039] The present invention has the advantages of simple process flow, continuous stability, mature equipment, energy saving and environmental protection. After use, the titanium tetrachloride liquid in the titanium tetrachloride slurry can be greatly reduced, and the maximum capacity of the titanium tetrachloride refined tailings entering the slurry evaporation furnace can be increased, the evaporation efficiency of the slurry in the evaporation furnace can be increased, the utilization rate of the crude titanium tetrachloride can be increased, and the recovery rate of titanium tetrachloride can be increased as a whole. The method and system of the present invention are easy to implement and have obvious economic benefits, so they can be fully promoted and applied on-site at titanium tetrachloride refining enterprises at home and abroad.

[0040] like Figure 2 As shown, the present invention provides a system for recovering titanium tetrachloride from titanium tetrachloride slurry, the system comprising an evaporation device 100 (for example, an evaporation furnace), a gas storage device 200, an atomization device 300, a heat exchange device 400 and a condensation device 500. The system of the present invention should be isolated from air influence and not be corroded during operation.

[0041] The evaporation device 100 comprises a first evaporation device slurry inlet 101 for introducing a first titanium tetrachloride slurry, a second evaporation device slurry inlet 102 for introducing a dried second titanium tetrachloride slurry, an evaporation device gas outlet 103 and an evaporation device slag outlet 104. The evaporation device 100 is used to perform evaporation treatment on titanium tetrachloride slurry.

[0042] The gas storage device 200 includes a gas storage device inlet 201 and a gas storage device outlet 202 . The gas storage device inlet 201 is connected to the evaporation device gas outlet 103 . The gas storage device 200 is used to store the titanium tetrachloride gas evaporated by the evaporation device 100 .

[0043] The atomizing device 300 includes an atomizing device slurry inlet 301 and an atomizing device slurry outlet 302. The second titanium tetrachloride slurry enters the atomizing device 300 through the atomizing device slurry inlet 301. The atomizing device 300 performs atomization treatment on the second titanium tetrachloride slurry.

[0044] The heat exchange device 400 includes a heat exchange device mud inlet 401, a heat exchange device mud outlet 402, a heat exchange device gas inlet 403 and a heat exchange device gas outlet 404. The heat exchange device mud inlet 401 is connected to the atomization device mud outlet 302, the heat exchange device mud outlet 402 is connected to the evaporation device second mud inlet 102, and the heat exchange device gas inlet 403 is connected to the gas storage device outlet 202. The heat exchange device mud inlet 401 and the heat exchange device gas outlet 404 are located at the upper part of the heat exchange device 400, and the heat exchange device mud outlet 402 and the heat exchange device gas inlet 403 are located at the bottom of the heat exchange device 400.

[0045] The condensing device 500 comprises a condensing device inlet 501 and a condensing device outlet 502 . The condensing device inlet 501 is connected to the heat exchange device gas outlet 404 , and the condensing device outlet 502 is connected to the crude titanium tetrachloride storage device 900 .

[0046] In one embodiment, the system further includes a first dust removal device 700, a second dust removal device 800 and a slag storage device 600. The first dust removal device 700 includes a first dust removal device inlet 701 and a first dust removal device outlet 702. The first dust removal device inlet 701 is connected to the evaporation device gas outlet 103, and the first dust removal device outlet 702 is connected to the gas storage device inlet 201. The second dust removal device 800 includes a second dust removal device inlet 801 and a second dust removal device outlet 802. The second dust removal device inlet 801 is connected to the heat exchange device gas outlet 404, and the second dust removal device outlet 802 is connected to the condensation device inlet 501. The slag storage device 600 is connected to the evaporation device slag discharge port 104.

[0047] like Figure 2 As shown by the arrow in , the first titanium tetrachloride slurry enters the evaporation device 100, and the obtained high-temperature titanium tetrachloride gas is dedusted by the first dust removal device 700 and then enters the gas storage device 200. The second titanium tetrachloride slurry is atomized by the atomization device 300 and then enters the heat exchange device 400. At the same time, the high-temperature titanium tetrachloride gas in the gas storage device 200 is sent to the heat exchange device 400 to dry the second titanium tetrachloride slurry. The titanium tetrachloride gas after heat exchange is dedusted by the second dust removal device 800 and then enters the condensation device 500 for condensation treatment. The crude titanium tetrachloride finally obtained enters the crude titanium tetrachloride storage device 900. In addition, the dried second titanium tetrachloride slurry continues to enter the evaporation device 100 for evaporation treatment, and then the above process is repeated. Figure 2As shown by the arrow in, those skilled in the art should understand that, as needed, the high-temperature titanium tetrachloride gas in the gas storage device 200 can also directly enter the condensation device 500 for condensation treatment after dust removal through the second dust removal device 800.

[0048] The specific embodiments of the present invention are described in detail below. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0049] Example 1 S10, adding the first titanium tetrachloride slurry with a concentration of 50 g / ml into the evaporation device, raising the temperature in the evaporation device to 200° C., and heating for 2 hours to obtain a high-temperature first titanium tetrachloride gas.

[0050] S20, passing the first titanium tetrachloride gas after dust removal into the gas storage device until the pressure of the gas storage device rises to 30 MPa, and stopping the delivery of the first titanium tetrachloride gas to the gas storage device.

[0051] S30, opening the atomizing device pipeline, passing the second titanium tetrachloride slurry into the atomizing device for atomization treatment, and obtaining an atomized second titanium tetrachloride slurry.

[0052] S40, passing the atomized second titanium tetrachloride slurry into the heat exchange device, and simultaneously passing the first titanium tetrachloride gas in the gas storage device into the heat exchange device to obtain the dried second titanium tetrachloride slurry and the first titanium tetrachloride gas after heat exchange, wherein the concentration of the dried second titanium tetrachloride slurry is 300 g / ml.

[0053] S50, the first titanium tetrachloride gas after dust removal and heat exchange enters a condensation device, and is condensed to obtain crude titanium tetrachloride.

[0054] S60, passing the dried second titanium tetrachloride slurry obtained in step S40 into an evaporation device for evaporation treatment to obtain a second titanium tetrachloride gas. When the material level of the transported dried second titanium tetrachloride slurry in the evaporation device reaches 50% of the maximum material level of the evaporation device, transport the second titanium tetrachloride gas to the gas storage device, and clean up the tailings in the evaporation device.

[0055] S70, continue to repeat the above steps. The yield of titanium tetrachloride gas in 20 hours reaches 98%, and the slag discharge time is 4 hours. The titanium tetrachloride slurry processing capacity is 1.5 times the capacity of the evaporation furnace.

[0056] Example 2 S10, adding the first titanium tetrachloride slurry with a concentration of 200 g / ml into the evaporation device, raising the temperature in the evaporation device to 300° C., and heating for 6 hours to obtain a high-temperature first titanium tetrachloride gas.

[0057] S20, passing the first titanium tetrachloride gas after dust removal into the gas storage device until the pressure of the gas storage device rises to 60 MPa, and stopping the delivery of the first titanium tetrachloride gas to the gas storage device.

[0058] S30, opening the atomizing device pipeline, passing the second titanium tetrachloride slurry into the atomizing device for atomization treatment, and obtaining an atomized second titanium tetrachloride slurry.

[0059] S40, passing the atomized second titanium tetrachloride slurry into the heat exchange device, and simultaneously passing the first titanium tetrachloride gas in the gas storage device into the heat exchange device to obtain the dried second titanium tetrachloride slurry and the first titanium tetrachloride gas after heat exchange, wherein the concentration of the dried second titanium tetrachloride slurry is 350 g / ml.

[0060] S50, the first titanium tetrachloride gas after dust removal and heat exchange enters a condensation device, and is condensed to obtain crude titanium tetrachloride.

[0061] S60, passing the dried second titanium tetrachloride slurry obtained in step S40 into an evaporation device for evaporation treatment to obtain a second titanium tetrachloride gas. When the material level of the transported dried second titanium tetrachloride slurry in the evaporation device reaches 60% of the maximum material level of the evaporation device, transport the second titanium tetrachloride gas to the gas storage device, and clean up the tailings in the evaporation device.

[0062] S70, continue to repeat the above steps. The yield of titanium tetrachloride gas in 17 hours reaches 98%, and the slag discharge time is 3.5 hours. The titanium tetrachloride slurry processing capacity is 1.5 times the capacity of the evaporation furnace.

[0063] Example 3 S10, adding the first titanium tetrachloride slurry with a concentration of 150 g / ml into the evaporation device, raising the temperature in the evaporation device to 400° C., and heating for 8 hours to obtain a high-temperature first titanium tetrachloride gas.

[0064] S20, passing the first titanium tetrachloride gas after dust removal into the gas storage device until the pressure of the gas storage device rises to 80 MPa, and stopping the delivery of the first titanium tetrachloride gas to the gas storage device.

[0065] S30, opening the atomizing device pipeline, passing the second titanium tetrachloride slurry into the atomizing device for atomization treatment, and obtaining an atomized second titanium tetrachloride slurry.

[0066] S40, passing the atomized second titanium tetrachloride slurry into the heat exchange device, and simultaneously passing the first titanium tetrachloride gas in the gas storage device into the heat exchange device to obtain the dried second titanium tetrachloride slurry and the first titanium tetrachloride gas after heat exchange, wherein the concentration of the dried second titanium tetrachloride slurry is 400 g / ml.

[0067] S50, the first titanium tetrachloride gas after dust removal and heat exchange enters a condensation device, and is condensed to obtain crude titanium tetrachloride.

[0068] S60, passing the dried second titanium tetrachloride slurry obtained in step S40 into an evaporation device for evaporation treatment to obtain a second titanium tetrachloride gas. When the material level of the transported dried second titanium tetrachloride slurry in the evaporation device reaches 70% of the maximum material level of the evaporation device, transport the second titanium tetrachloride gas to the gas storage device, and clean up the tailings in the evaporation device.

[0069] S70, continue to repeat the above steps. The yield of titanium tetrachloride gas within 16 hours reaches 98%, and the slag discharge time is 3.5 hours. The titanium tetrachloride slurry processing capacity is 1.6 times the capacity of the evaporation furnace.

[0070] Example 4 S10, adding the first titanium tetrachloride slurry with a concentration of 300 g / ml into the evaporation device, raising the temperature in the evaporation device to 500° C., and heating for 10 hours to obtain a high-temperature first titanium tetrachloride gas.

[0071] S20, passing the first titanium tetrachloride gas after dust removal into the gas storage device until the pressure of the gas storage device rises to 150 MPa, and stopping the delivery of the first titanium tetrachloride gas to the gas storage device.

[0072] S30, opening the atomizing device pipeline, passing the second titanium tetrachloride slurry into the atomizing device for atomization treatment, and obtaining an atomized second titanium tetrachloride slurry.

[0073] S40, passing the atomized second titanium tetrachloride slurry into the heat exchange device, and simultaneously passing the first titanium tetrachloride gas in the gas storage device into the heat exchange device to obtain the dried second titanium tetrachloride slurry and the first titanium tetrachloride gas after heat exchange, wherein the concentration of the dried second titanium tetrachloride slurry is 500 g / ml.

[0074] S50, the first titanium tetrachloride gas after dust removal and heat exchange enters a condensation device, and is condensed to obtain crude titanium tetrachloride.

[0075] S60, passing the dried second titanium tetrachloride slurry obtained in step S40 into an evaporation device for evaporation treatment to obtain a second titanium tetrachloride gas. When the material level of the transported dried second titanium tetrachloride slurry in the evaporation device reaches 80% of the maximum material level of the evaporation device, transport the second titanium tetrachloride gas to the gas storage device, and clean up the tailings in the evaporation device.

[0076] S70, continue to repeat the above steps. The yield of titanium tetrachloride gas within 15 hours reaches 98%, and the slag discharge time is 3 hours. The titanium tetrachloride slurry processing capacity is 1.6 times the capacity of the evaporation furnace.

[0077] Comparative Example 1 The titanium tetrachloride slurry with a concentration of 50g / ml is directly introduced into the slurry evaporation furnace, heated to 300℃ and kept warm for 22h. During evaporation, the crude titanium tetrachloride gas is collected until the titanium tetrachloride slurry is completely evaporated, and the slag is discharged. The slag discharge time is 4h. The yield of titanium tetrachloride gas reaches 97%, and the titanium tetrachloride slurry treatment capacity is 1 times the capacity of the evaporation furnace.

[0078] Comparative Example 2 A portion of the titanium tetrachloride slurry with a concentration of 150g / ml is returned to the chlorination furnace for temperature control, and the other portion is passed into the slurry evaporation furnace and heated to 300°C for 22 hours. During evaporation, crude titanium tetrachloride gas is collected until the titanium tetrachloride slurry is completely evaporated, and slag is discharged for 4 hours. The yield of titanium tetrachloride gas reaches 97%, and the titanium tetrachloride slurry treatment capacity is 1 times the capacity of the evaporation furnace.

[0079] The evaporation time of the present invention is 15h to 20h, while the evaporation time of the traditional pulp evaporation furnace evaporation recovery method is 22h. In comparison, the evaporation recovery time of the present invention is shortened by 2h to 7h, and the recovery efficiency is increased. The method of the present invention adds an improved atomization drying system and an intermediate gas storage device for titanium tetrachloride. After implementation, titanium tetrachloride slurry can be processed in large quantities. Compared with the traditional method, the processing volume can be increased by more than 50%, providing a large-scale carbon tetrachloride slurry processing technical solution for large-scale chlorination furnace expansion. The titanium tetrachloride gas storage device can also be used as pipeline dredging gas, which greatly reduces the probability of system blockage.

[0080] It should be particularly pointed out that the various components or steps in the above-mentioned embodiments can be cross-linked, replaced, added, or deleted with each other. Therefore, the combinations formed by these reasonable arrangements and combinations should also fall within the scope of protection of the present invention, and the scope of protection of the present invention should not be limited to the embodiments.

[0081] 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 recovering titanium tetrachloride from titanium tetrachloride slurry, characterized in that: The following steps are involved: S10, transporting the first titanium tetrachloride slurry to an evaporation device for evaporation treatment to obtain a first titanium tetrachloride gas; S20, transporting the first titanium tetrachloride gas to a gas storage device; S30, atomizing the second titanium tetrachloride slurry to obtain an atomized second titanium tetrachloride slurry; S40, using the first titanium tetrachloride gas obtained in step S20 to dry the atomized second titanium tetrachloride slurry obtained in step S30, to obtain the dried second titanium tetrachloride slurry and the first titanium tetrachloride gas after heat exchange; S50, condensing the first titanium tetrachloride gas obtained after heat exchange in step S40 to obtain crude titanium tetrachloride; S60, transporting the dried second titanium tetrachloride slurry obtained in step S40 to an evaporation device for evaporation treatment to obtain a second titanium tetrachloride gas, and performing a slag discharge treatment on the evaporation device; S70, repeat the above steps.

2. The method according to claim 1, characterized in that In step S10, the concentration of the first titanium tetrachloride slurry is 50 g / ml to 300 g / ml.

3. The method according to claim 1, characterized in that In step S10, the evaporation temperature is 200°C to 500°C, and the heating time is 2h to 10h.

4. The method according to claim 1, characterized in that: In step S20, when the pressure of the gas storage device rises to 30 MPa to 150 MPa, the first titanium tetrachloride gas is stopped from being delivered to the gas storage device.

5. The method according to claim 1, characterized in that: In step S40, the concentration of the dried second titanium tetrachloride slurry is 300 g / ml to 500 g / ml.

6. The method according to claim 1, characterized in that In step S60, when the material level of the conveyed dried second titanium tetrachloride slurry in the evaporation device reaches 50% to 80% of the maximum material level of the evaporation device, the second titanium tetrachloride gas is conveyed to the gas storage device, and then the evaporation device is deslagging.

7. The method according to claim 1, characterized in that Before step S20, a step of removing dust from the first titanium tetrachloride gas is also included.

8. The method according to claim 1, characterized in that Before step S50, a step of removing dust from the first titanium tetrachloride gas after heat exchange is also included.

9. A system for recovering titanium tetrachloride from titanium tetrachloride slurry, characterized in that: The system comprises: An evaporation device, the evaporation device comprising a first slurry inlet for introducing a first titanium tetrachloride slurry, a second slurry inlet for introducing a dried second titanium tetrachloride slurry, a gas outlet for the evaporation device, and a slag outlet for the evaporation device; A gas storage device, the gas storage device comprising a gas storage device inlet and a gas storage device outlet, the gas storage device inlet is connected to the gas outlet of the evaporation device, and the gas storage device is used to store titanium tetrachloride gas; an atomizing device, wherein the atomizing device comprises an atomizing device mud inlet and an atomizing device mud outlet, and the second titanium tetrachloride slurry enters the atomizing device through the atomizing device mud inlet; a heat exchange device, the heat exchange device comprising a heat exchange device mud inlet, a heat exchange device mud outlet, a heat exchange device gas inlet and a heat exchange device gas outlet, the heat exchange device mud inlet is connected to the atomization device mud outlet, the heat exchange device mud outlet is connected to the evaporation device second mud inlet, and the heat exchange device gas inlet is connected to the gas storage device outlet; and A condensing device, wherein the condensing device comprises a condensing device inlet and a condensing device outlet, wherein the condensing device inlet is communicated with the gas outlet of the heat exchange device, and the condensing device outlet is communicated with the crude titanium tetrachloride storage device.

10. The system according to claim 9, characterized in that The system further comprises: a first dust removal device, the first dust removal device comprising a first dust removal device inlet and a first dust removal device outlet, the first dust removal device inlet is connected to the evaporation device gas outlet, and the first dust removal device outlet is connected to the gas storage device inlet; a second dust removal device, the second dust removal device comprising a second dust removal device inlet and a second dust removal device outlet, the second dust removal device inlet is connected to the gas outlet of the heat exchange device, and the second dust removal device outlet is connected to the condensing device inlet; and A slag storage device is connected to a slag discharge port of the evaporation device.

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