Device for inhibiting self-polymerization in tetrafluoroethylene production

Abstract

The utility model provides a device for inhibiting self-polymerization in tetrafluoroethylene production. The device comprises a tetrafluoroethylene crude product tank, a compressor, a sulfuric acid tower and a deoxidizing tower, an outlet of the tetrafluoroethylene crude product tank is communicated with a first-stage inlet of the compressor, a first-stage exhaust port of the compressor is sequentially connected with the sulfuric acid tower and the deoxidizing tower in series, a tower top gas phase outlet of the deoxidizing tower is connected with a condenser, a gas phase outlet of the condenser is communicated with a second-stage inlet of the compressor, and a second-stage exhaust port of the compressor is connected with a rectification device; a spraying layer, a plurality of composite tower plate layers and a liquid storage tank are arranged in the deoxidizing tower from top to bottom; each composite tower plate layer comprises a tower plate and a metal wire mesh filler arranged at the lower part of the tower plate; the liquid storage tank is communicated with the spraying layer through a circulating pump, an air inlet is formed in one side of the lower portion of the deoxidizing tower, and an air outlet is formed in the top of the deoxidizing tower and connected with a condenser. According to the invention, self-polymerization of tetrafluoroethylene monomers in tetrafluoroethylene production is avoided.

Description

TECHNICAL FIELD

[0001] The application relates to the fluorine chemical technology field, in particular to a device for inhibiting self-polymerization in tetrafluoroethylene production. BACKGROUND

[0002] Tetrafluoroethylene is an important fluorine-containing monomer, is the basic raw material of many fluorine-containing copolymers (such as polytetrafluoroethylene, amorphous fluorine resin, perfluoroether elastomer, etc.), is also the intermediate of many fluorine-containing compounds (such as hexafluoropropylene, tetrafluoropropyl alcohol, etc.), and has a huge demand. At present, tetrafluoroethylene is mainly prepared by the water vapor dilution cracking method. The water vapor dilution cracking method has the characteristics of high conversion rate of difluorochloromethane, high selectivity of product tetrafluoroethylene, low raw material consumption, simple reactor structure, reliable operation and difficulty in coking.

[0003] However, in the production process of tetrafluoroethylene, in the presence of oxygen and water at the same time, the self-polymerization of active fluorine-containing olefin monomers is intensified. The self-polymerization phenomenon has great harm to normal production, often causes pipe and equipment blockage, so that the production operation cannot continue, and more seriously, local overheating occurs, chain reaction occurs and explosion occurs, which has great safety hidden danger. It also causes unstable operation of the oxygen removal tower and poor oxygen removal effect, thereby affecting the stable operation of the rectification system and restricting the high-load production of tetrafluoroethylene. CONTENT OF THE UTILITY MODEL

[0004] The application provides a device for inhibiting self-polymerization in tetrafluoroethylene production to solve the above problems mentioned in the background.

[0005] The application provides a device for inhibiting self-polymerization in tetrafluoroethylene production, which comprises a tetrafluoroethylene crude product tank, a compressor, a sulfuric acid tower and an oxygen removal tower.

[0006] The outlet of the tetrafluoroethylene crude product tank is communicated with the first inlet of the compressor, the first exhaust port of the compressor is sequentially connected with the sulfuric acid tower and the oxygen removal tower, the gas phase outlet of the top of the oxygen removal tower is connected with a condenser, the gas phase outlet of the condenser is communicated with the second inlet of the compressor, and the second exhaust port of the compressor is connected with a rectification device.

[0007] The inside of the oxygen removal tower is provided with a spraying layer, a plurality of composite tray layers and a liquid storage tank from top to bottom, and the composite tray layer comprises a tray and a metal wire mesh filler arranged at the lower part of the tray.

[0008] The liquid storage tank is communicated with the spraying layer through a circulating pump, one side of the lower part of the oxygen removal tower is provided with an air inlet, and the top is provided with an air outlet, and the air outlet is connected with the condenser.

[0009] Optionally, the composite tray layer further comprises a liquid receiving plate, a lower liquid plate and an overflow weir, the cross section of the fluid passage formed by the lower liquid plate and the side wall of the oxygen removal tower, the area sum of the liquid receiving plate and the tray is equal to the cross section of the oxygen removal tower.

[0010] Multiple air holes are opened through the tray. The top of the metal wire mesh packing is in contact with the bottom of the tray. Overflow weirs are vertically arranged on both sides of the tray. The liquid receiving plate is vertically connected to one overflow weir. The lower liquid plate is arranged vertically, and the top of the lower liquid plate is connected to the bottom of another overflow weir.

[0011] Optionally, the pore size of the wire mesh filler is larger than the pore size of the air pores.

[0012] Optionally, a metal mesh layer is provided above the tray, with the thickness of the metal mesh layer being 1 / 4 to 1 / 3 of the tray thickness.

[0013] Optionally, the pore size of the metal mesh layer is larger than the pore size of the air pores.

[0014] Optionally, a quench cooler, a graphite cooler, a water washing tower, and an alkali washing tower are connected sequentially between the crude tetrafluoroethylene tank and the compressor.

[0015] The outlet of the tetrafluoroethylene reactor is connected to the inlet of the quench cooler, and the gas phase outlet of the alkali washing tower is connected to the inlet of the tetrafluoroethylene crude product tank.

[0016] Optionally, demisters are installed at the top of both the sulfuric acid tower and the deoxygenation tower.

[0017] The apparatus for inhibiting self-polymerization in the production of tetrafluoroethylene provided in this application avoids the self-polymerization of tetrafluoroethylene monomers during the production of tetrafluoroethylene, and has the following advantages compared with the prior art:

[0018] (1) By conveying crude tetrafluoroethylene to a sulfuric acid tower for dehydration, the sulfuric acid absorbs the moisture in the crude tetrafluoroethylene, and then conveying it to a deoxygenation tower for deoxygenation, the self-polymerization of tetrafluoroethylene monomers during transportation can be avoided, preventing blockage of pipelines and equipment, and thus ensuring smooth reaction. At the same time, production safety is improved, thereby increasing the yield of tetrafluoroethylene. The deoxygenated crude tetrafluoroethylene is fed into a condenser for condensation, and the trace amounts of terpenes carried with the crude tetrafluoroethylene are condensed into liquid and separated from the tetrafluoroethylene, thus purifying the tetrafluoroethylene. During the ascent of the crude tetrafluoroethylene in the deoxygenation tower, it passes through multiple trays and metal wire mesh packing in sequence. Due to the pores distributed in the metal wire mesh packing, the crude tetrafluoroethylene and terpene droplets can be dispersed and mixed, prolonging the contact time between the crude tetrafluoroethylene and terpenes, and increasing the material flow path, thereby improving the combination of terpenes and oxygen in the crude tetrafluoroethylene, enhancing the deoxygenation efficiency, and thus greatly reducing the self-polymerization of tetrafluoroethylene monomers, avoiding blockage of pipelines and equipment, and improving production efficiency. Meanwhile, the use of metal wire mesh packing reduces tower pressure, increases operating gas velocity, and enhances separation efficiency, thereby improving deoxygenation efficiency.

[0019] (2) The crude tetrafluoroethylene first passes through the metal mesh packing, and then passes through multiple gas holes on the tray to carry out gas-liquid mass transfer and heat transfer. The terpene reacts with oxygen in the crude tetrafluoroethylene, so as to achieve the purpose of removing oxygen from the crude tetrafluoroethylene, so that the production process of tetrafluoroethylene can be carried out smoothly and safely. The pore size of the metal mesh packing is larger than the pore size of the gas hole. When the crude tetrafluoroethylene passes through the composite tray layer, the flow cross section changes from large to small, and then the flow rate changes from small to large after entering the gas hole, and the kinetic energy is also improved. The collision with the terpene is more intense, and then the contact between the crude tetrafluoroethylene and the terpene is more sufficient, and the oxygen removal efficiency is improved.

[0020] (3) By setting the metal mesh layer, and the thickness of the metal mesh layer is 1 / 4-1 / 3 of the thickness of the tray, the crude tetrafluoroethylene passes through the composite tray layer and contacts the terpene, and then passes through the metal mesh layer after being output from the gas hole. The setting of the metal mesh layer not only further improves the mixing time of the crude tetrafluoroethylene and the terpene, but also removes the foam and liquid droplets entrained in the rising process of the crude tetrafluoroethylene, thereby improving the oxygen removal efficiency and reducing the load of the oxygen removal tower. BRIEF DESCRIPTION OF DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are some embodiments of the present application, and those skilled in the art can also obtain other drawings according to these drawings without creative labor.

[0022] Figure 1 The structure schematic diagram of the device for inhibiting self-polymerization in the production of tetrafluoroethylene provided by an embodiment of the present application is shown in the figure.

[0023] Figure 2 The structure schematic diagram of the oxygen removal tower provided by an embodiment of the present application is shown in the figure.

[0024] Figure 3 The structure schematic diagram of the composite tray layer provided by an embodiment of the present application is shown in the figure.

[0025] Figure 4 The structure schematic diagram of the device for inhibiting self-polymerization in the production of tetrafluoroethylene provided by another embodiment of the present application is shown in the figure.

[0026] Explanation of reference signs:

[0027] 1: tetrafluoroethylene crude tank, 2: compressor, 3: sulfuric acid tower, 4: deoxidizing tower, 5: condenser, 6: quencher, 7: graphite cooler, 8: water washing tower, 9: alkali washing tower, 210: first-stage inlet, 220: first-stage exhaust port, 230: second-stage inlet, 240: second-stage exhaust port, 310: mist eliminator, 410: spray layer, 420: composite tray layer, 421: tray, 422: wire mesh packing, 423: liquid receiving plate, 424: liquid outlet plate, 425: overflow weir, 430: liquid storage tank, 440: circulating pump, 450: gas inlet, 460: gas outlet, 470: metal mesh layer, 4211: air hole. DETAILED DESCRIPTION

[0028] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application are described clearly and completely below. Obviously, the described embodiments are some but not all of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0029] As shown in Figure 1 and Figure 2 , the present application provides a device for inhibiting self-polymerization in tetrafluoroethylene production, comprising: a tetrafluoroethylene crude tank 1, a compressor 2, a sulfuric acid tower 3 and a deoxidizing tower 4.

[0030] The outlet of the tetrafluoroethylene crude tank 1 is in communication with the first-stage inlet 210 of the compressor 2, the first-stage exhaust port 220 of the compressor 2 is in series with the sulfuric acid tower 3 and the deoxidizing tower 4 in turn, the overhead gas phase outlet of the deoxidizing tower 4 is connected with a condenser 5, the gas phase outlet of the condenser 5 is in communication with the second-stage inlet 230 of the compressor 2, and the second-stage exhaust port 240 of the compressor 2 is connected with a rectification device.

[0031] The deoxidizing tower 4 is internally provided with a spray layer 410, a plurality of composite tray layers 420 and a liquid storage tank 430 from top to bottom, and the composite tray layer 420 comprises a tray 421 and wire mesh packing 422 arranged at the lower part of the tray 421.

[0032] The liquid storage tank 430 is in communication with the spray layer 410 through a circulating pump 440, the lower part of one side of the deoxidizing tower 4 is provided with a gas inlet 450, and the top is provided with a gas outlet 460, and the gas outlet 460 is connected with the condenser 5.

[0033] Specifically, in the production process of tetrafluoroethylene, after the reaction in the reaction process is completed, tetrafluoroethylene crude product is obtained, and the crude product is temporarily stored in a tetrafluoroethylene crude product tank 1. The tetrafluoroethylene crude product is subjected to primary pressurization through a first inlet 210 of a compressor 2, and is transported to a sulfuric acid tower 3 for water removal. The tetrafluoroethylene crude product moves upward in the sulfuric acid tower 3, and is countercurrently contacted with sulfuric acid sprayed from the upper part of the sulfuric acid tower 3. The sulfuric acid absorbs the water in the tetrafluoroethylene crude product, and falls to the bottom of the sulfuric acid tower 3. The tetrafluoroethylene crude product after water removal continues to rise to the top of the sulfuric acid tower 3, and is output from the top of the tower, enters an oxygen removal tower 4 through an air inlet 450, and is subjected to oxygen removal. After water removal in the sulfuric acid tower 3 and oxygen removal in the oxygen removal tower 4, self-polymerization of tetrafluoroethylene monomers in the transportation process can be avoided, and the pipes and equipment are prevented from being blocked, thereby enabling the reaction to proceed smoothly. At the same time, the production safety is improved, and the yield of tetrafluoroethylene is improved.

[0034] The liquid storage tank 430 at the bottom of the oxygen removal tower 4 stores terpene, which is transported to the spray layer 410 by a circulating pump 440. The terpene is sprayed from top to bottom, and at the same time, the tetrafluoroethylene crude product moves upward. The tetrafluoroethylene crude product is countercurrently contacted with the terpene. The terpene contains a large number of unsaturated double bonds, which can combine with oxygen in the tetrafluoroethylene crude product when contacted with the tetrafluoroethylene crude product, thereby greatly reducing the oxygen content in the tetrafluoroethylene crude product, and further reducing the self-polymerization of tetrafluoroethylene monomers and improving the stability of production. The tetrafluoroethylene crude product is continuously subjected to oxygen removal during the upward movement, reaches the top of the oxygen removal tower 4, and is discharged through an air outlet 460. The tetrafluoroethylene crude product discharged from the air outlet 460 enters a condenser 5 for condensation, and a small amount of terpene entrained with the tetrafluoroethylene crude product is condensed. The non-condensable gas tetrafluoroethylene discharged from the condenser 5 enters the second inlet 230 of the compressor 2 after the second pressurization, and is transported to a rectification device for further purification to obtain tetrafluoroethylene product, thereby realizing the production of tetrafluoroethylene.

[0035] As the crude tetrafluoroethylene rises within the deoxygenation tower 4, it sequentially passes through multiple composite tray layers 420. Each composite tray layer 420 includes a tray 421 and a metal wire mesh packing 422 disposed below the tray 421. Each time the crude tetrafluoroethylene passes through the composite tray layer 420, it first passes through the metal wire mesh packing 422. Because the metal wire mesh packing 422 has pores, it can repeatedly disperse and mix the crude tetrafluoroethylene with terpene droplets, prolonging the contact time between the crude tetrafluoroethylene and the terpene. Simultaneously, it increases the material flow path, thereby improving the binding of oxygen between the terpene and the crude tetrafluoroethylene, enhancing deoxygenation efficiency, and significantly reducing the self-polymerization of tetrafluoroethylene monomers. This avoids blockages in pipelines and equipment, improving production efficiency. Meanwhile, the wire mesh packing 422 is a structured packing. When crude tetrafluoroethylene and terpenes pass through the wire mesh packing 422, the pressure distribution on the surface of the packing is uniform. Compared with the bulk packing in traditional technology, the tower pressure is reduced, the operating gas velocity is higher, the separation degree is increased, and the deoxygenation efficiency is improved. After passing through the wire mesh packing 422, the crude tetrafluoroethylene then passes through the tray 421, where it comes into contact with the terpenes again for deoxygenation, further improving the deoxygenation efficiency, further preventing the self-polymerization of tetrafluoroethylene monomers, and increasing the yield and productivity of tetrafluoroethylene.

[0036] This application achieves the avoidance of tetrafluoroethylene monomer self-polymerization during tetrafluoroethylene production through the aforementioned scheme. By conveying crude tetrafluoroethylene to a sulfuric acid tower for dehydration, where sulfuric acid absorbs the moisture, followed by deoxygenation in a deoxygenation tower, the self-polymerization of tetrafluoroethylene monomers during transportation is prevented, avoiding blockages in pipelines and equipment, thus ensuring smooth reaction. This also improves production safety and consequently increases the yield of tetrafluoroethylene. The deoxygenated crude tetrafluoroethylene is then fed into a condenser for condensation, where trace amounts of terpenes carried along with the crude tetrafluoroethylene are condensed and separated from the tetrafluoroethylene, achieving purification of the tetrafluoroethylene. During its ascent within the deoxygenation tower, crude tetrafluoroethylene (TEF) passes sequentially through multiple trays and wire mesh packing. The porous structure of the wire mesh packing repeatedly disperses and mixes the TEF and terpene droplets, prolonging their contact time and increasing the material flow path. This enhances the binding of oxygen between the terpene and TEF, improving deoxygenation efficiency and significantly reducing the self-polymerization of TEF monomers. This prevents blockages in pipelines and equipment, thereby increasing production efficiency. Furthermore, the use of wire mesh packing lowers the tower pressure, increases the operating gas velocity, and enhances the separation degree, further improving deoxygenation efficiency.

[0037] like Figure 2 As shown, optionally, the composite tower plate layer 420 also includes a liquid receiving plate 423, a lower liquid plate 424 and an overflow weir 425. The total area of ​​the fluid channel formed by the lower liquid plate 424 and the inner wall of the deaerator 4, the liquid receiving plate 423 and the tower plate 421 is equal to the cross-section of the deaerator 4.

[0038] A plurality of air holes 4211 are formed through the tray 421, the top of the wire mesh packing 422 is connected to the bottom of the tray 421, the two sides of the tray 421 are respectively provided with overflow weirs 425 vertically, and the receiving plate 423 is connected to one of the overflow weirs 425 vertically, and the liquid outlet plate 424 is arranged vertically and the top of the liquid outlet plate 424 is connected to the bottom of the other overflow weir 425.

[0039] Specifically, the two sides of the tray 421 are respectively provided with overflow weirs 425 vertically, the space formed by the overflow weir 425 on one side, the side wall of the deoxidizing tower 4 and the receiving plate 423 is a receiving area, and the space formed by the overflow weir 425 on the other side, the side wall of the corresponding deoxidizing tower 4 and the liquid outlet plate 424 is a liquid outlet area, the liquid outlet area is used to provide a channel for liquid flow, and the receiving area and the liquid outlet area of the adjacent two composite tray layers 420 are aligned in the vertical direction. The sum of the fluid cross sections of the receiving plate 423, the tray 421 and the liquid outlet area is equal to the cross section of the deoxidizing tower 4. The liquid falls through the liquid outlet plate 424 to the receiving plate 423 of the next composite tray layer 420, and then overflows the overflow weir 425 to the tray 421 from the receiving plate 423, and the crude tetrafluoroethylene and the terpene pass through the plurality of air holes 4211 on the tray 421 after passing through the wire mesh packing 422, so that the gas-liquid mass transfer and heat transfer are carried out, the terpene reacts with the oxygen in the crude tetrafluoroethylene, the purpose of deoxidizing the crude tetrafluoroethylene is achieved, and the production process of tetrafluoroethylene can be carried out smoothly and safely.

[0040] Optionally, the pore size of the wire mesh packing 422 is larger than the pore size of the air hole 4211.

[0041] Specifically, the crude tetrafluoroethylene has a certain kinetic energy during the rising process, and the pore size of the wire mesh packing 422 is larger than the pore size of the air hole 4211, so that when the crude tetrafluoroethylene passes through the composite tray layer 420, the flow cross section changes from large to small, the flow rate changes from small to large after entering the air hole 4211, and the kinetic energy also increases, so that the collision with the terpene is more violent, and the contact between the crude tetrafluoroethylene and the terpene is more sufficient, thereby improving the deoxidizing efficiency.

[0042] As shown in Figure 3 Optionally, a metal mesh layer 470 is further arranged above the tray 421, and the thickness of the metal mesh layer 470 is 1 / 4-1 / 3 of the thickness of the tray 421.

[0043] Optionally, the pore size of the metal mesh layer 470 is larger than the pore size of the air hole 4211.

[0044] Specifically, the tetrafluoroethylene crude product is output from the gas hole 4211 after being contacted with the terpene through the composite tray layer 420, and then passes through the metal mesh layer 470. The metal mesh layer 470 is not only arranged to further improve the mixing time of the tetrafluoroethylene crude product and the terpene, but also can remove the foam and liquid droplets entrained by the tetrafluoroethylene crude product in the ascending process, thereby improving the oxygen removal efficiency and reducing the load of the oxygen removal tower 4.

[0045] Meanwhile, the thickness of the metal mesh layer 470 is 1 / 4-1 / 3 of the thickness of the tray 421. If the metal mesh layer 470 is too thick, the liquid phase terpene is not easy to enter the gas hole 4211. If the metal mesh layer 470 is too thin, the mixing effect cannot be enhanced. The aperture of the metal mesh layer 470 is larger than that of the wire mesh packing 422.

[0046] As shown in Figure 4 Optionally, the tetrafluoroethylene crude product tank 1 is further sequentially connected with a quencher 6, a graphite cooler 7, a water washing tower 8 and an alkali washing tower 9.

[0047] The outlet of the tetrafluoroethylene reactor is in communication with the inlet of the quencher 6, and the gas phase outlet of the alkali washing tower 9 is in communication with the inlet of the tetrafluoroethylene crude product tank 1.

[0048] Specifically, the tetrafluoroethylene crude product is cooled and the reaction is terminated after entering the quencher 6 after being output from the tetrafluoroethylene reactor, and then sequentially passes through the graphite cooler 7 to remove acid (such as hydrogen chloride), and then sequentially passes through the water washing tower 8 and the alkali washing tower 9 to further remove acid, thereby purifying the tetrafluoroethylene crude product and being beneficial to the corrosion of the equipment in the subsequent process of passing through the sulfuric acid tower 3 and the oxygen removal tower 4.

[0049] Optionally, the top of the sulfuric acid tower 3 and the oxygen removal tower 4 is provided with a mist eliminator 310.

[0050] Specifically, the mist eliminator 310 is used to remove the terpene liquid droplets entrained in the tetrafluoroethylene crude product at the top, thereby reducing the load of the subsequent condenser 5.

[0051] The technical scheme of the present application will be described in detail below with specific examples.

[0052] The device for inhibiting self-polymerization in the production of tetrafluoroethylene in the embodiment has the following operation process in the specific work:

[0053] The crude tetrafluoroethylene is cooled and the reaction is terminated after being output from the tetrafluoroethylene reactor into the quencher 6, and sequentially passes through the graphite cooler 7 to remove acid (such as hydrogen chloride), and then sequentially passes through the water washing tower 8 and the alkali washing tower 9 to further remove acid, so as to purify the crude tetrafluoroethylene and obtain the crude tetrafluoroethylene. The crude tetrafluoroethylene is temporarily stored in the crude tetrafluoroethylene tank 1, and is subjected to primary pressure increase through the primary inlet 210 of the compressor 2, and is then transported into the sulfuric acid tower 3 to remove water. The crude tetrafluoroethylene moves from bottom to top in the sulfuric acid tower 3, and is countercurrently contacted with the sulfuric acid sprayed from the upper part of the sulfuric acid tower 3. The sulfuric acid absorbs the water in the crude tetrafluoroethylene, and falls to the bottom of the sulfuric acid tower 3. The crude tetrafluoroethylene after water removal continues to rise to the top of the sulfuric acid tower 3, and is output from the top, and is then input into the oxygen removal tower 4 through the gas inlet 450 of the oxygen removal tower 4 to remove oxygen from the crude tetrafluoroethylene.

[0054] The accumulator tank 430 at the bottom of the oxygen removal tower 4 stores terpene. The terpene is transported into the spraying layer 410 by the circulating pump 440, and is sprayed from top to bottom. At the same time, the crude tetrafluoroethylene moves from bottom to top, and is countercurrently contacted with the terpene. The terpene combines with the oxygen in the crude tetrafluoroethylene, so as to greatly reduce the oxygen content in the crude tetrafluoroethylene. The crude tetrafluoroethylene is continuously subjected to oxygen removal in the process of rising, and reaches the top of the oxygen removal tower 4, and is then discharged through the gas outlet 460. The crude tetrafluoroethylene discharged from the gas outlet 460 is input into the condenser 5 to be condensed. The trace amount of terpene entrained with the crude tetrafluoroethylene is condensed. The non-condensable gas tetrafluoroethylene finally discharged from the condenser 5 is subjected to secondary pressure increase through the secondary inlet 230 of the compressor 2, and is then transported into the rectification device to be further purified, so as to obtain the tetrafluoroethylene product.

[0055] The crude tetrafluoroethylene rises in the oxygen removal tower 4, and sequentially passes through a plurality of composite tower plate layers 420. The composite tower plate layer 420 includes the tower plate 421 and the metal wire mesh packing 422 arranged at the lower part of the tower plate 421. When the crude tetrafluoroethylene passes through the composite tower plate layer 420, it first passes through the metal wire mesh packing 422. Since the metal wire mesh packing 422 is distributed with pores, it can disperse and mix the crude tetrafluoroethylene and the terpene droplets, so as to prolong the contact time of the crude tetrafluoroethylene and the terpene. Then, the crude tetrafluoroethylene passes through the tower plate 421 again, and is subjected to oxygen removal again, so as to further improve the oxygen removal efficiency.

[0056] The pore diameter of the metal wire mesh packing 422 is greater than the pore diameter of the air hole 4211. When the crude tetrafluoroethylene passes through the composite tower plate layer 420, the flow cross section changes from large to small, and then the flow rate changes from small to large after entering the air hole 4211, and the kinetic energy is also improved. The collision between the crude tetrafluoroethylene and the terpene is more intense, so as to make the crude tetrafluoroethylene and the terpene contact more fully, and improve the oxygen removal efficiency.

[0057] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, and are not limited thereto; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand; it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement to part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. An apparatus for inhibiting self-polymerization in tetrafluoroethylene production, characterized by comprising: The utility model relates to a kind of tetrafluoroethylene production device, including: Tetrafluoroethylene crude tank (1), compressor (2), sulfuric acid tower (3) and oxygen removal tower (4); The outlet of the tetrafluoroethylene crude tank (1) is communicated with the first inlet (210) of the compressor (2), the first exhaust port (220) of the compressor (2) is connected in series with the sulfuric acid tower (3) and the oxygen removal tower (4) in sequence, the overhead gas phase outlet of the oxygen removal tower (4) is connected with a condenser (5), the gas phase outlet of the condenser (5) is communicated with the second inlet (230) of the compressor (2), and the second exhaust port (240) of the compressor (2) is connected with a rectification device. A plurality of composite tray layers (420) and liquid storage tanks (430) are arranged in the oxygen removal tower (4) from top to bottom, and the composite tray layer (420) comprises a tray (421) and a metal wire mesh filler (422) arranged at the lower part of the tray (421). The liquid storage tank (430) is communicated with the spray layer (410) through a circulating pump (440), and the lower side of the oxygen removal tower (4) is provided with an air inlet (450), and the top is provided with an air outlet (460), and the air outlet (460) is connected with the condenser (5).

2. The apparatus according to claim 1, wherein The composite tray layer (420) further comprises a liquid receiving plate (423), a lower liquid plate (424) and an overflow weir (425), the cross section of the fluid passage formed by the inner side wall of the oxygen removal tower (4), the area sum of the lower liquid plate (424), the liquid receiving plate (423) and the tray (421) is equal to the cross section of the oxygen removal tower (4). A plurality of air holes (4211) are provided through the tray (421), the top of the metal wire mesh filler (422) is connected with the bottom of the tray (421), and the overflow weirs (425) are vertically arranged on both sides of the tray (421), and the liquid receiving plate (423) is vertically connected with one of the overflow weirs (425), and the lower liquid plate (424) is vertically arranged, and the top of the lower liquid plate (424) is connected with the bottom of the other overflow weir (425).

3. The apparatus according to claim 2, wherein The pore size of the metal wire mesh filler (422) is larger than the pore size of the air hole (4211).

4. The apparatus according to claim 3, wherein A metal mesh layer (470) is further arranged above the tray (421), and the thickness of the metal mesh layer (470) is 1 / 4-1 / 3 of the thickness of the tray (421).

5. The apparatus according to claim 4, wherein The pore size of the metal mesh layer (470) is larger than the pore size of the air hole (4211).

6. The apparatus according to claim 3, wherein The tetrafluoroethylene crude tank (1) is further connected with a quencher (6), a graphite cooler (7), a water washing tower (8) and an alkali washing tower (9) in sequence. The outlet of the tetrafluoroethylene reactor is communicated with the inlet of the quencher (6), and the gas phase outlet of the alkali washing tower (9) is communicated with the inlet of the tetrafluoroethylene crude tank (1).

7. The apparatus for inhibiting self-polymerization in tetrafluoroethylene production according to any one of claims 1 to 6, characterized by, The top of the sulfuric acid tower (3) and the oxygen removal tower (4) is provided with a mist eliminator (310).

Images