Energy-saving preparation device and preparation method for high-purity phosphorus oxychloride

Abstract

The invention discloses an energy-saving preparation device and method for high-purity phosphorus oxychloride, the preparation device comprises a raw material mixing mechanism, a micro-channel reactor, a condensation mechanism and a raw material treatment mechanism, the raw material mixing mechanism comprises a mixing device, and the mixing device is used for mixing phosphorus trichloride and oxygen; the micro-channel reactor comprises a feed distribution pipe, a plurality of micro-channel pipes are mounted on the feed distribution pipe, and a reflux collection pipe is mounted at one end, far away from the feed distribution pipe, of each micro-channel pipe. High-purity phosphorus oxychloride filtered by the raw material treatment mechanism is mixed with oxygen in the micro-channel reactor to react, and the micro-channel reactor is used for preparing phosphorus oxychloride in a reaction medium circulating flow mode, so that the reaction rate and the reaction effect of phosphorus oxychloride and oxygen are improved; the preparation time of the phosphorus oxychloride is shortened, and meanwhile, the generation of byproducts is reduced, so that the purity of the prepared phosphorus oxychloride is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of phosphorus oxychloride preparation, and particularly relates to an energy-saving preparation device and a preparation method for high-purity phosphorus oxychloride. Background Art

[0002] Phosphorus oxychloride is an inorganic compound with the chemical formula POCl3. It is a colorless and transparent liquid. Phosphorus oxychloride is a key raw material in semiconductor, photovoltaic and optical fiber manufacturing, and its purity directly affects the device performance.

[0003] In the traditional preparation of phosphorus oxychloride, it is prepared by the reaction of phosphorus trichloride and oxygen in a reaction kettle. In the reaction kettle, the stirring device stirs to make phosphorus trichloride and oxygen mix and react. In the existing preparation process, the contact between oxygen and phosphorus trichloride is not sufficient, and a long reaction time is required, resulting in high energy consumption and many by-products in the preparation of phosphorus oxychloride; at the same time, the heat generated during the reaction is not effectively recovered, and the energy utilization rate is low.

[0004] The information disclosed in this background art section is only intended to enhance the overall understanding of the present invention and should not be regarded as an admission or any form of suggestion that this information constitutes prior art already known to those of ordinary skill in the art. Summary of the Invention

[0005] The purpose of the present invention is to provide an energy-saving preparation device and a preparation method for high-purity phosphorus oxychloride, which can solve the problems of long reaction time, high energy consumption and many by-products caused by insufficient contact between oxygen and phosphorus trichloride during the preparation of phosphorus oxychloride; at the same time, it can also solve the problem of low energy utilization rate caused by ineffective heat recovery during the preparation of phosphorus oxychloride.

[0006] In order to achieve the above purpose, the technical solution provided by a specific embodiment of the present invention is as follows:

[0007] An energy-saving preparation device for high-purity phosphorus oxychloride, comprising:

[0008] A raw material mixing mechanism, including a mixing device, which is used for mixing phosphorus trichloride and oxygen so that oxygen and phosphorus trichloride are preliminarily mixed and then undergo subsequent reactions.

[0009] Microchannel reactor, including a feed distribution pipe, on which a plurality of microchannel pipes are installed. One end of the plurality of microchannel pipes away from the feed distribution pipe is installed with a reflux collection pipe, and a dynamic disperser is installed in each of the plurality of microchannel pipes. Phosphorus trichloride and oxygen pass through and are mixed in the microchannel pipe through a co-current microchannel, so that phosphorus oxychloride and oxygen are fully mixed through the co-current microchannel. And a dynamic disperser is arranged in the microchannel pipe, so that when oxygen and phosphorus trichloride flow in the microchannel pipe, the dynamic disperser forces the microbubble dispersion of oxygen, greatly improving the mixing effect of oxygen and phosphorus oxychloride, thereby shortening the time required for the preparation of phosphorus oxychloride, and further improving the preparation efficiency of phosphorus oxychloride.

[0010] Condensing mechanism, including a condenser housing, in which a plurality of condensing pipes are installed, and a waste heat recovery member is installed between the condenser housing and the mixing device. Phosphorus trichloride and oxygen need to be prepared into phosphorus oxychloride through sufficient mixing reaction. Therefore, phosphorus oxychloride and oxygen need to circulate in the microchannel pipe. Therefore, in order to control the temperature of the reaction medium during the circulation of phosphorus oxychloride and oxygen, the waste heat in the reaction medium is recovered by setting the condensing pipe. While realizing the recovery and utilization of waste heat, the temperature of the reaction medium can be regulated, so that the reaction medium reacts within the temperature range required for the preparation of phosphorus oxychloride.

[0011] Raw material treatment mechanism, including a filtering device housing, in which a primary filtering member and a secondary filtering member are installed, and the primary filtering member is installed on one side close to the liquid inlet of the filtering device housing. In order to reduce the impurities in the raw materials, the phosphorus trichloride is filtered twice by the primary filtering member and the secondary filtering member to ensure that the phosphorus trichloride transported into the mixing device does not contain solid particle impurities, and to ensure that no solid particles enter the microchannel pipe, thereby ensuring the smooth flow of phosphorus trichloride and oxygen in the microchannel pipe and improving the purity of the preparation of phosphorus oxychloride.

[0012] In one or more embodiments of the present invention, a sandwich layer is arranged in the mixing device, and a heating device is installed in the sandwich layer. When the temperature of the circulating reaction medium is lower than the reaction range, the temperature can be compensated by the heating device. A liquid inlet pipe is fixedly connected to the feed inlet of the mixing device, and the liquid inlet pipe is used for transporting phosphorus trichloride. A first regulating valve is installed on the liquid inlet pipe, and the first regulating valve is used for controlling the flow rate and pressure of the transported phosphorus trichloride. An air inlet pipe is fixedly connected to the side wall of the liquid inlet pipe, and the air inlet pipe is used for transporting oxygen. A second regulating valve is installed on the air inlet pipe, and the second regulating valve is used for controlling the flow rate and pressure of the transported oxygen. A first discharge pipe is installed at the discharge outlet of the mixing device, and phosphorus trichloride and oxygen are transported through the first discharge pipe after being mixed in the mixing device. A reflux pipe is fixedly connected to the bottom of the liquid inlet pipe, and the reaction medium returns to the mixing device through the reflux pipe.

[0013] In one or more embodiments of the present invention, the microchannel tube is arranged in a ring shape, which increases the length of the microchannel tube arranged in a limited space, increases the flow time of phosphorus trichloride and oxygen in the microchannel tube, and thus improves the mixing and contact effect. The microchannel tube is made of quartz material. Since the reaction of phosphorus trichloride and oxygen will produce highly corrosive hydrogen chloride, the microchannel tube is made of corrosion-resistant quartz material. The inner diameter of the microchannel tube is set to 1-1.5 mm. One end of the first discharge pipe far from the mixing device is fixedly connected to the feed distribution pipe, so that the phosphorus trichloride and oxygen mixed by the mixing device are transported into the feed distribution pipe through the first discharge pipe. The bottom of the reflux collection pipe is fixedly connected with a second discharge pipe, and a third regulating valve is installed on the second discharge pipe. The reaction medium in the microchannel tube flows into the reflux collection pipe and then is transported through the second discharge pipe. The third regulating valve is used to control the circulation reaction or discharge of the reaction medium transported by the second discharge pipe.

[0014] In one or more embodiments of the present invention, the dynamic disperser includes a plurality of spiral guide vanes. The plurality of spiral guide vanes are fixedly connected to the inner side wall of the microchannel tube in an interlaced manner, so that when the reaction medium flows in the microchannel tube, the oxygen microbubbles are forced to disperse through the plurality of spiral guide vanes arranged in an interlaced manner, reducing the escape loss, thereby improving the oxygen utilization rate. And the spiral guide vanes can disturb the reaction medium, prolonging the residence time of the reaction medium in the microchannel tube, improving the reaction rate and reaction effect of phosphorus trichloride and oxygen, thereby shortening the preparation time of phosphorus oxychloride and reducing the generation of by-products during the preparation of phosphorus oxychloride, and improving the purity of the prepared phosphorus oxychloride. The plurality of spiral guide vanes are all arranged to incline downward in the direction of the medium flow, so that the arrangement of the spiral guide vanes can disperse the oxygen microbubbles without causing interception of the reaction medium, avoiding the reaction medium remaining in the microchannel tube, and making the shear force direction match the fluid direction, resulting in a better dispersion effect on the medium. A plurality of micro-through holes are formed in a penetrating manner on one side of the spiral guide vane close to the side wall of the microchannel tube, further improving the effect of forcing the oxygen microbubbles to disperse through the micro-through holes. A plurality of micro-grooves are formed on the upper surface of one side of the spiral guide vane far from the inner side wall of the microchannel tube, thus forming a multi-scale flow disturbance. The spacing of the spiral guide vanes is set to 5-10 mm, increasing the number of shear action times per unit length while balancing the pressure drop and energy consumption. The included angle between the inclination angle of the spiral guide vane and the central axis of the microchannel tube is set to 30-60 degrees.

[0015] In one or more embodiments of the present invention, the condenser tube includes a first housing and a second housing. The second housing is fixedly connected to the outside of the first housing. An accommodation chamber is formed between the first housing and the second housing, and the accommodation chamber is filled with a nano-phase change material. A fluid channel is provided inside the first housing. A plurality of fins are fixedly connected to the outer side wall of the second housing. The first housing is made of a graphite material, and the second housing and the fins are both made of a copper alloy material. When the reaction medium flows in the fluid channel, the heat of the reaction medium is transferred through the first housing, and the nano-phase change material can absorb the heat. When the nano-phase change material absorbs enough heat, it will undergo a phase change, and the absorbed heat is stored and released through the second housing and the fins at the same time, so as to realize the cooling of the reaction medium through the nano-phase change material, and the absorbed heat is recycled through storage. When the temperature of the reaction medium drops, the nano-phase change material releases heat when solidifying, so as to heat the reaction medium in the fluid channel through the heat released by the nano-phase change material. Therefore, through the condenser tube, the temperature during the reaction of phosphorus trichloride and oxygen is adjusted. When the temperature of the reaction medium is high, the temperature is recovered and stored through the condenser tube for utilization; when the temperature of the reaction medium is low, the heat stored in the condenser tube is used to heat the reaction medium, realizing the recycling of heat and greatly improving the energy utilization rate.

[0016] In one or more embodiments of the present invention, a distributor is installed on one side of the condenser housing close to the feed port. The inlet of the fluid channel of the first housing is communicated with the distributor, so that the reaction medium entering the condenser housing is evenly distributed into a plurality of condenser tubes through the distributor. A collector is installed on one side of the condenser housing close to the discharge port. The outlet of the fluid channel of the first housing is communicated with the collector, so that the reaction medium is collected through the collector after heat transfer in the condenser tube. An exhaust pipe is installed on the collector. The upper end of the exhaust pipe penetrates through the condenser housing and is located outside the condenser housing. A gas-liquid separator is installed at the upper end of the exhaust pipe. Since hydrogen chloride gas is generated during the reaction of phosphorus trichloride and oxygen, in order to treat the hydrogen chloride gas, after the heat of the hydrogen chloride is absorbed through the condenser tube, the hydrogen chloride gas is subjected to solid-liquid separation through the gas-liquid separator and then discharged into the hydrogen chloride treatment device for treatment.

[0017] In one or more embodiments of the present invention, a return pipe is fixedly connected to the outer side wall of the condenser housing feed port. A fourth regulating valve is installed on the return pipe. The end of the return pipe away from the condenser housing is fixedly connected to the side wall of the second discharge pipe, so that the reaction medium conveyed by the second discharge pipe can be conveyed into the condenser housing through the return pipe for heat transfer, and then flow back into the mixing device for cyclic reaction. The end of the return pipe away from the liquid inlet pipe is installed on the outer side wall of the liquid outlet of the condenser housing. An air delivery pipe is installed on the bottom side wall of the condenser housing. A fifth regulating valve is installed on the air delivery pipe. The end of the air inlet pipe away from the liquid inlet pipe is installed on the top side wall of the condenser housing. Oxygen is conveyed into the condenser housing through the air delivery pipe. When the oxygen flows in the condenser housing, it can absorb the heat transferred by the second housing and the fins, and then the preheated oxygen is conveyed into the liquid inlet pipe through the air inlet pipe, so that when oxygen and phosphorus trichloride are mixed in the mixing device, they are preheated by the recovered heat, improving the reaction effect of the two.

[0018] In one or more embodiments of the present invention, the primary filter element is set as a sintered metal filter element, and the pore diameter of the sintered metal filter element is set to 20 μm, so as to filter out larger solid particles in phosphorus trichloride through the primary filter element. The secondary filter element is set as a ceramic fiber filter membrane, and the pore diameter of the ceramic fiber filter membrane is set to 5 μm, and sub-micron suspended solids and colloidal particles are removed through the secondary filter element. An inert gas delivery pipe is installed on one side of the filter device housing at the feed port. Inert gas is provided into the filter device housing through the inert gas delivery pipe to maintain an inert environment in the filter device housing and prevent hydrolysis of phosphorus trichloride. An anti-blow pipe is installed on one side of the filter device housing at the discharge port. Inert gas for anti-blowing is provided into the filter device housing through the anti-blow pipe to clean the primary filter element and the secondary filter element. The end of the liquid inlet pipe away from the mixing device is fixedly connected to the liquid outlet of the filter device housing, so that the phosphorus trichloride filtered by the filter device housing is conveyed into the mixing device through the liquid inlet pipe.

[0019] A method for energy-saving preparation of high-purity phosphorus oxychloride, the preparation method comprising:

[0020] S1. Convey high-purity phosphorus trichloride into the filter device housing through an infusion pipe, and filter the phosphorus trichloride through the primary filter element and the secondary filter element; at the same time, convey oxygen into the condenser housing through an air delivery pipe, and recycle the waste heat in the condenser housing through the oxygen;

[0021] S2. The filtered phosphorus oxychloride is conveyed into the mixing device through the liquid inlet pipe, and the oxygen after absorbing heat is conveyed into the mixing device through the return pipe. In the mixing device, phosphorus oxychloride and oxygen are preliminarily mixed to obtain a reaction medium;

[0022] S3. The reaction medium is transported into the feed distribution pipe through the first discharge pipe. The feed distribution pipe distributes the reaction medium to flow in multiple microchannel tubes. Under the action of the dynamic disperser in the microchannel tubes, the microbubble dispersion of oxygen in the medium is realized. Under the action of the microchannel tubes and the dynamic disperser, the reaction efficiency of phosphorus trichloride and oxygen is improved. The reaction medium in the microchannel tubes flows into the reflux collection pipe;

[0023] S4. The reaction medium in the reflux collection pipe flows into the condenser housing through the return pipe. In the condenser housing, the waste heat in the reaction medium is absorbed by the condenser tube. The waste heat absorbed by the condenser tube is used for preheating oxygen and compensating the heat of the reaction medium, so that the temperature of the reaction medium in the microchannel tubes is within the reaction range;

[0024] S5. After the temperature of the reaction medium is adjusted in the condenser housing, it is transported into the mixing device through the return pipe, and then transported into the microchannel tubes through the mixing device for circulation. Phosphoryl chloride is prepared by circulating and flowing in the microchannel tubes, and the prepared phosphoryl chloride is discharged through the third regulating valve.

[0025] In one or more embodiments of the present invention, the temperature of the reaction medium in the microchannel tubes is controlled at 50-80 °C, and the pressure of the reaction medium in the microchannel tubes is controlled at 0.1-0.3 MPa.

[0026] Compared with the prior art, the present invention has the following advantages:

[0027] 1. The present invention is provided with a microchannel reactor. Phosphorus trichloride and oxygen are mixed in the microchannel reactor through a co-current microchannel, and a dynamic disperser is arranged in the microchannel. The oxygen is forced to disperse into bubbles through the dynamic disperser, and at the same time, the reaction medium is dispersed through turbulence, so that phosphorus trichloride and oxygen can be fully mixed in the microchannel, greatly improving the mixing effect of oxygen and phosphoryl chloride, thereby shortening the time required for the preparation of phosphoryl chloride, and further improving the preparation efficiency of phosphoryl chloride;

[0028] 2. The present invention is provided with a condensation mechanism. The reaction medium after mixing in the microchannel reactor flows back to the condensation mechanism. The waste heat in the reaction medium is recovered and stored by the nano-phase change material in the condenser tube. Oxygen is preheated in the condensation structure and then mixed with phosphorus trichloride to realize the recovery and utilization of waste heat, and the temperature of the reaction medium is adjusted by the heat absorption and release of the nano-phase change material, greatly improving the energy utilization rate;

[0029] 3. The high-purity phosphorus oxychloride filtered by the raw material treatment mechanism of the present invention reacts with oxygen in the microchannel reactor. The microchannel reactor prepares phosphorus oxychloride by circulating the reaction medium, which improves the reaction rate and effect of phosphorus trichloride and oxygen, shortens the preparation time of phosphorus oxychloride, reduces the generation of by-products, and thus improves the purity of the prepared phosphorus oxychloride. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments recorded in the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0031] Figure 1 Schematic diagram of a high-purity phosphorus oxychloride energy-saving preparation device in an embodiment of the present invention;

[0032] Figure 2 Stereogram of a high-purity phosphorus oxychloride energy-saving preparation device in an embodiment of the present invention;

[0033] Figure 3 Cross-sectional view of a high-purity phosphorus oxychloride energy-saving preparation device in an embodiment of the present invention;

[0034] Figure 4 Sectional view of a high-purity phosphorus oxychloride energy-saving preparation device in an embodiment of the present invention;

[0035] Figure 5 For the present invention Figure 4 Schematic diagram at location A;

[0036] Figure 6 Internal schematic diagram of the microchannel reactor of the present invention;

[0037] Figure 7 Connection schematic diagram of the raw material mixing mechanism and the condensation mechanism of the present invention;

[0038] Figure 8 Cross-sectional view of the condensation structure of the present invention;

[0039] Figure 9 For the present invention Figure 8 Schematic diagram at location B;

[0040] Figure 10 Cross-sectional view of the raw material treatment mechanism of the present invention.

[0041] Main reference numeral description:

[0042] 1 - Raw material mixing mechanism, 11 - Mixing device, 12 - Interlayer, 13 - Heating device, 14 - Liquid inlet pipe, 15 - First regulating valve, 16 - Gas inlet pipe, 17 - Second regulating valve, 18 - First discharge pipe, 19 - Return pipe, 2 - Microchannel reactor, 21 - Feed distribution pipe, 22 - Microchannel pipe, 23 - Return material collection pipe, 24 - Spiral guide vane, 25 - Micro through hole, 26 - Micro groove, 27 - Protective shell, 28 - Second discharge pipe, 29 - Third regulating valve, 3 - Condensing mechanism, 31 - Condenser housing, 32 - Distributor, 33 - Condensing pipe, 3301 - First housing, 3302 - Second housing, 3303 - Nano phase change material, 3304 - Fins, 34 - Recoverer, 35 - Return material pipe, 36 - Fourth regulating valve, 37 - Exhaust pipe, 38 - Gas-liquid separator, 39 - Gas transmission pipe, 310 - Fifth regulating valve, 4 - Raw material treatment mechanism, 41 - Filter device housing, 42 - Primary filter element, 43 - Secondary filter element, 44 - Liquid delivery pipe, 45 - Inert gas delivery pipe, 46 - Backwashing pipe. Detailed implementation mode

[0043] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present invention.

[0044] As Figures 1 to 4 shown, a high-purity phosphorus oxychloride energy-saving preparation device in an embodiment of the present invention includes a raw material mixing mechanism 1, a microchannel reactor 2, a condensing mechanism 3, and a raw material treatment mechanism 4.

[0045] As Figures 1 to 4 shown, the raw material mixing mechanism 1 includes a mixing device 11, and the mixing device 11 is used for mixing phosphorus trichloride and oxygen, so that oxygen and phosphorus trichloride are preliminarily mixed for subsequent reactions.

[0046] As Figure 4 and Figure 7As shown in the figure, a sandwich layer 12 is provided inside the mixing device 11, and a heating device 13 is installed inside the sandwich layer 12. When the temperature of the circulating reaction medium is lower than the reaction range, temperature compensation can be carried out through the heating device 13. A liquid inlet pipe 14 is fixedly connected to the feed inlet of the mixing device 11. The liquid inlet pipe 14 is used for transporting phosphorus trichloride, and a first regulating valve 15 is installed on the liquid inlet pipe 14. The first regulating valve 15 is used for controlling the flow rate and pressure of the transported phosphorus trichloride. An air inlet pipe 16 is fixedly connected to the side wall of the liquid inlet pipe 14. The air inlet pipe 16 is used for transporting oxygen, and a second regulating valve 17 is installed on the air inlet pipe 16. The second regulating valve 17 is used for controlling the flow rate and pressure of the transported oxygen. A first discharge pipe 18 is installed at the discharge outlet of the mixing device 11. After phosphorus trichloride and oxygen are mixed in the mixing device 11, they are transported through the first discharge pipe 18. A reflux pipe 19 is fixedly connected to the bottom of the liquid inlet pipe 14. The reaction medium is refluxed into the mixing device 11 through the reflux pipe 19.

[0047] As Figures 1 to 4 and Figure 7 shown in the figure, the microchannel reactor 2 includes a feed distribution pipe 21. A plurality of microchannel pipes 22 are installed on the feed distribution pipe 21. A reflux collection pipe 23 is installed at one end of the plurality of microchannel pipes 22 away from the feed distribution pipe 21. Dynamic dispersers are installed in all of the plurality of microchannel pipes 22. Phosphorus trichloride and oxygen pass through and are mixed in the microchannel pipes 22 through a co-current microchannel, so that phosphorus oxychloride and oxygen are mixed sufficiently through the co-current microchannel. And a dynamic disperser is provided in the microchannel pipes 22. When oxygen and phosphorus trichloride flow in the microchannel pipes 22, the dynamic disperser forces the microbubbles of oxygen to be dispersed, greatly improving the mixing effect of oxygen and phosphorus oxychloride, thereby shortening the time required for the preparation of phosphorus oxychloride, and further improving the preparation efficiency of phosphorus oxychloride.

[0048] As Figure 4 and Figure 6As shown, the microchannel tube 22 is arranged in a ring shape, which increases the length of the microchannel tube 22 arranged in a limited space, increases the flow time of phosphorus trichloride and oxygen in the microchannel tube 22, and thus improves the mixing and contact effect. The microchannel tube 22 is made of quartz material. Since the reaction of phosphorus trichloride and oxygen will produce highly corrosive hydrogen chloride, the microchannel tube 22 is made of corrosion-resistant quartz material. The inner diameter of the microchannel tube 22 is set to 1-1.5 mm. One end of the first discharge pipe 18 far from the mixing device 11 is fixedly connected to the feed distribution pipe 21, so that the phosphorus trichloride and oxygen mixed by the mixing device 11 are transported into the feed distribution pipe 21 through the first discharge pipe 18. The bottom of the reflux collection pipe 23 is fixedly connected with a second discharge pipe 28, and a third regulating valve 29 is installed on the second discharge pipe 28. The reaction medium in the microchannel tube 22 flows into the reflux collection pipe 23 and then is transported through the second discharge pipe 28. The third regulating valve 29 is used to control the reaction medium transported by the second discharge pipe 28 to carry out cyclic reaction or discharge.

[0049] As Figure 4 Combined Figure 5 As shown, the dynamic disperser includes a plurality of spiral guide vanes 24. The plurality of spiral guide vanes 24 are fixedly connected to the inner side wall of the microchannel tube 22 in an interlaced manner, so that when the reaction medium flows in the microchannel tube 22, the forced dispersion of oxygen microbubbles is achieved through the plurality of spiral guide vanes 24 arranged in an interlaced manner, reducing the escape loss, thereby improving the oxygen utilization rate. And the spiral guide vanes 24 can disturb the reaction medium, prolonging the residence time of the reaction medium in the microchannel tube 22, improving the reaction rate and reaction effect of phosphorus trichloride and oxygen, thereby shortening the preparation time of phosphorus oxychloride, and reducing the generation of by-products during the preparation of phosphorus oxychloride, and improving the purity of the prepared phosphorus oxychloride. The plurality of spiral guide vanes 24 are all arranged to incline downward in the direction of the medium flow, so that the setting of the spiral guide vanes 24 can achieve the dispersion of oxygen microbubbles without causing the interception of the reaction medium, avoiding the reaction medium remaining in the microchannel tube 22, and making the shear force direction match the fluid direction, resulting in a better dispersion effect on the medium. A plurality of micro-through holes 25 are formed in a penetrating manner on one side of the spiral guide vane 24 close to the side wall of the microchannel tube 22, and the forced dispersion effect of oxygen microbubbles is further improved through the micro-through holes 25. A plurality of micro-grooves 26 are formed on the upper surface of one side of the spiral guide vane 24 far from the inner side wall of the microchannel tube 22, so as to form multi-scale flow disturbances.

[0050] Preferably, the spacing of the spiral guide vanes 24 is set to 5-10 mm, which increases the number of shear action times per unit length while balancing the pressure drop and energy consumption. The included angle between the inclination angle of the spiral guide vane 24 and the central axis of the microchannel tube 22 is set to 30-60 degrees.

[0051] As Figure 3As shown, the microchannel reactor 2 is provided with a protective shell 27 to protect the microchannel tube 22 through the protective shell 27.

[0052] As Figures 1 to 4 and Figure 8 shown, the condensation mechanism 3 includes a condenser housing 31. A plurality of condenser tubes 33 are installed inside the condenser housing 31, and a waste heat recovery component is installed between the condenser housing 31 and the mixing device 11. Phosphorus trichloride and oxygen need to be prepared into phosphorus oxychloride through sufficient mixing reaction. Therefore, phosphorus oxychloride and oxygen need to circulate in the microchannel tube 22. Therefore, in order to control the temperature of the reaction medium during the circulation of phosphorus oxychloride and oxygen, the waste heat in the reaction medium is recovered by setting the condenser tubes 33. While realizing the recovery and utilization of waste heat, the temperature of the reaction medium can be regulated so that the reaction medium reacts within the temperature range required for the preparation of phosphorus oxychloride.

[0053] As Figure 8 Combined Figure 9 shown, the condenser tube 33 includes a first housing 3301 and a second housing 3302. The second housing 3302 is fixedly connected to the outside of the first housing 3301. An accommodation chamber is formed between the first housing 3301 and the second housing 3302, and a nano-phase change material 3303 is filled in the accommodation chamber. A fluid channel is provided inside the first housing 3301. A plurality of fins 3304 are fixedly connected to the outer side wall of the second housing 3302. The first housing 3301 is made of graphite material, and the second housing 3302 and the fins 3304 are both made of copper alloy material. When the reaction medium flows in the fluid channel, the heat of the reaction medium will be transferred through the first housing 3301, and the nano-phase change material 3303 can absorb the heat. When the nano-phase change material 3303 absorbs enough heat, it will undergo a phase change, and the absorbed heat is stored and released through the second housing 3302 and the fins 3304. Thus, the temperature of the reaction medium is reduced through the nano-phase change material 3303, and the absorbed heat is recovered and utilized through storage. When the temperature of the reaction medium drops, the nano-phase change material 3303 releases heat when solidifying, so as to heat the reaction medium in the fluid channel through the heat released by the nano-phase change material 3303. Therefore, through the condenser tube 33, the temperature during the reaction of phosphorus trichloride and oxygen is regulated. When the temperature of the reaction medium is high, the temperature is recovered and stored through the condenser tube 33 for utilization; when the temperature of the reaction medium is low, the heat stored in the condenser tube 33 is used to heat the reaction medium, realizing the recovery and utilization of heat and greatly improving the energy utilization rate.

[0054] As Figure 8 Combined Figure 9As shown, a distributor 32 is installed on one side of the condenser housing 31 near the feed port. The inlet of the fluid passage of the first housing 3301 communicates with the distributor 32, so that the reaction medium entering the condenser housing 31 is evenly distributed into a plurality of condenser tubes 33 through the distributor 32. A collector 34 is installed on one side of the condenser housing 31 near the discharge port. The outlet of the fluid passage of the first housing 3301 communicates with the collector 34, so that the reaction medium is collected through the collector 34 after heat transfer in the condenser tubes 33. An exhaust pipe 37 is installed on the collector 34. The upper end of the exhaust pipe 37 penetrates through the condenser housing 31 and is located outside the condenser housing 31. A gas-liquid separator 38 is installed at the upper end of the exhaust pipe 37. Since hydrogen chloride gas is generated when phosphorus trichloride reacts with oxygen, in order to treat the hydrogen chloride gas, after the heat of the hydrogen chloride is absorbed by the condenser tube 33, the hydrogen chloride gas is subjected to solid-liquid separation through the gas-liquid separator 38 and then discharged into the hydrogen chloride treatment device for treatment.

[0055] As Figures 1 to 4 and Figure 7 As shown, a return pipe 35 is fixedly connected to the outer side wall of the feed port of the condenser housing 31. A fourth regulating valve 36 is installed on the return pipe 35. The end of the return pipe 35 away from the condenser housing 31 is fixedly connected to the side wall of the second discharge pipe 28, so that the reaction medium conveyed by the second discharge pipe 28 can be conveyed into the condenser housing 31 through the return pipe 35 for heat transfer, and then flows back into the mixing device 11 for cyclic reaction. The end of the return pipe 19 away from the liquid inlet pipe 14 is installed on the outer side wall of the liquid outlet of the condenser housing 31. An air delivery pipe 39 is installed on the bottom side wall of the condenser housing 31. A fifth regulating valve 310 is installed on the air delivery pipe 39. The end of the air inlet pipe 16 away from the liquid inlet pipe 14 is installed on the top side wall of the condenser housing 31. Oxygen is conveyed into the condenser housing 31 through the air delivery pipe 39. When the oxygen flows in the condenser housing 31, it can absorb the heat transferred by the second housing 3302 and the fins 3304, and then the preheated oxygen is conveyed into the liquid inlet pipe 14 through the air inlet pipe 16, so that the oxygen and phosphorus trichloride are preheated by the recovered heat when they are mixed in the mixing device 11, improving the reaction effect of the two.

[0056] As Figures 1 to 4 and Figure 10As shown in the figure, the raw material processing mechanism 4 includes a filtering device housing 41. Inside the filtering device housing 41, a primary filtering element 42 and a secondary filtering element 43 are installed. The primary filtering element 42 is installed on the side close to the liquid inlet of the filtering device housing 41. In order to reduce impurities in the raw material, the phosphorus trichloride is filtered twice through the primary filtering element 42 and the secondary filtering element 43 to ensure that the phosphorus trichloride transported into the mixing device 11 does not contain solid particle impurities, and to ensure that no solid particles enter the microchannel tube 22, thereby ensuring the smooth flow of phosphorus trichloride and oxygen in the microchannel tube 22 and improving the purity of the preparation of phosphorus oxychloride at the same time.

[0057] As Figure 10 shown, the primary filtering element 42 is set as a sintered metal filter element, and the pore diameter of the sintered metal filter element is set to 20 μm, so as to filter larger solid particles in the phosphorus trichloride through the primary filtering element 42. The secondary filtering element 43 is set as a ceramic fiber filter membrane, and the pore diameter of the ceramic fiber filter membrane is set to 5 μm, and sub-micron suspended matter and colloidal particles are removed through the secondary filtering element 43. An inert gas delivery pipe 45 is installed on one side of the filtering device housing 41 at the feed port, and inert gas is supplied into the filtering device housing 41 through the inert gas delivery pipe 45 to maintain an inert environment inside the filtering device housing 41 and prevent the hydrolysis of phosphorus trichloride. An anti-blow pipe 46 is installed on one side of the filtering device housing 41 at the discharge port, and inert gas for anti-blowing is supplied into the filtering device housing 41 through the anti-blow pipe 46 to clean the primary filtering element 42 and the secondary filtering element 43. One end of the liquid inlet pipe 14 far from the mixing device 11 is fixedly connected to the liquid outlet of the filtering device housing 41, so that the phosphorus trichloride filtered by the filtering device housing 41 is transported into the mixing device 11 through the liquid inlet pipe 14.

[0058] It should be noted that during the preparation process of phosphorus oxychloride, since the reaction medium is corrosive, the pipelines and equipment through which the reaction medium flows are all made of corrosion-resistant materials. At the same time, for the intelligent operation of this device, necessary sensors and electrical components are equipped, and the automatic or semi-automatic control of the present invention can be realized through a single-chip microcomputer or other control devices in cooperation with necessary sensors and electrical components, which are well-known to those skilled in the art and will not be elaborated here.

[0059] A method for energy-saving preparation of high-purity phosphorus oxychloride, the preparation method includes:

[0060] S1. Transport high-purity phosphorus trichloride into the filtering device housing 41 through the liquid delivery pipe 44, and filter the phosphorus trichloride through the primary filtering element 42 and the secondary filtering element 43; at the same time, transport oxygen into the condenser housing 31 through the gas delivery pipe 39, and recover and utilize the waste heat in the condenser housing 31 through the oxygen.

[0061] Specifically, phosphorus trichloride is transported into the filtration device housing 41 through the infusion tube 44, and inert gas is provided into the filtration device housing 41 through the inert gas delivery tube 45. The inert gas ensures that phosphorus trichloride does not hydrolyze when passing through the primary filter element 42 and the secondary filter element 43 in the filtration device housing 41. Oxygen is transported into the condenser housing 31 through the gas delivery pipe 39. When the oxygen flows in the condenser housing 31, it absorbs the heat absorbed by the condenser tube 33, enabling the oxygen to carry the waste heat for recycling.

[0062] S2. The filtered phosphorus oxychloride is transported into the mixing device 11 through the liquid inlet pipe 14, and the oxygen after absorbing heat is transported into the mixing device 11 through the return pipe 19. In the mixing device 11, phosphorus oxychloride and oxygen are preliminarily mixed to obtain a reaction medium.

[0063] Specifically, the phosphorus trichloride filtered by the filtration device housing 41 and the oxygen carrying heat are mixed in the mixing device 11, thereby preheating the raw materials during the preparation of phosphorus oxychloride through waste heat. While realizing heat recovery and utilization, the efficiency of phosphorus oxychloride preparation is improved by preheating and pre-mixing the raw materials.

[0064] S3. The reaction medium is transported into the feed distribution pipe 21 through the first discharge pipe 18. The feed distribution pipe 21 distributes the reaction medium to flow in multiple microchannel tubes 22. And under the action of the dynamic disperser in the microchannel tubes 22, microbubble dispersion of oxygen in the medium is achieved. Under the action of the microchannel tubes 22 and the dynamic disperser, the reaction efficiency of phosphorus trichloride and oxygen is improved. The reaction medium in the microchannel tubes 22 flows into the reflux collection pipe 23.

[0065] Specifically, the mixed solution of phosphorus oxychloride and oxygen flows in the microchannel tubes 22. When the mixed solution contacts the spiral guide vane 24, the spiral guide vane 24 can cause turbulence to the mixed solution, and dispersion of the mixed solution is achieved through shear force. At the same time, the spiral guide vane 24 will force microbubble dispersion of oxygen, greatly improving the contact effect between oxygen and phosphorus trichloride. At the same time, the micro through holes 25 and the micro grooves 26 further disturb the reaction medium, making the mixing of phosphorus oxychloride and oxygen more sufficient. Thus, the preparation time of phosphorus oxychloride is greatly shortened, the preparation efficiency of phosphorus oxychloride is improved, the generation of by-products is reduced, and the purity of phosphorus oxychloride is improved.

[0066] S4. The reaction medium in the reflux collection pipe 23 flows into the condenser housing 31 through the return pipe 35. In the condenser housing 31, the waste heat in the reaction medium is absorbed by the condenser tube 33. The waste heat absorbed by the condenser tube 33 is used for preheating oxygen and compensating the heat of the reaction medium, so that the temperature of the reaction medium in the microchannel tubes 22 is within the reaction range.

[0067] Specifically, when the high-temperature reaction medium flows in the condenser tube 33, the nano-phase change material 3303 will absorb and store heat. At the same time, the second housing 3302 and the fins 3304 release the heat absorbed by the nano-phase change material 3303, so that oxygen can absorb the heat to preheat the raw materials, thereby reducing the temperature of the reaction medium through the condenser tube 33, making the temperature of the reaction medium flowing back into the micro-channel tube 22 within the required range; when the temperature of the reaction medium entering the condenser tube 33 is low, the nano-phase change material 3303 can release heat to heat the reaction medium when it solidifies, thereby increasing the temperature of the reaction medium to the required range; enabling the temperature of the reaction medium to be adjusted through the condenser tube 33 by using waste heat, realizing the recovery and utilization of heat, and improving the energy utilization rate.

[0068] S5. After the temperature of the reaction medium is adjusted in the condenser housing 31, it is transported to the mixing device 11 through the return pipe 19, and then transported to the micro-channel tube 22 through the mixing device 11 for circulation. The phosphorus oxychloride is prepared by circulating in the micro-channel tube 22, and the prepared phosphorus oxychloride is discharged through the third regulating valve 29.

[0069] In one or more embodiments of the present invention, the temperature of the reaction medium in the micro-channel tube 22 is controlled at 50-80 °C, and the pressure of the reaction medium in the micro-channel tube 22 is controlled at 0.1-0.3 MPa.

[0070] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above-described exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present invention. Any reference signs in the claims should not be regarded as limiting the claims involved.

[0071] In addition, it should be understood that although this specification is described according to embodiments, not every embodiment only contains an independent technical solution. This narrative way of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. An energy-saving preparation device for high-purity phosphorus oxychloride, characterized in that, Including: A raw material mixing mechanism, including a mixing device for mixing phosphorus trichloride and oxygen; A microchannel reactor, including a feed distribution pipe, on which a plurality of microchannel pipes are installed. At the ends of the plurality of microchannel pipes far from the feed distribution pipe, a reflux collection pipe is installed, and a dynamic disperser is installed in each of the plurality of microchannel pipes; A condensation mechanism, including a condenser housing, in which a plurality of condenser pipes are installed, and a waste heat recovery component is installed between the condenser housing and the mixing device; A raw material treatment mechanism, including a filter device housing, in which a primary filter element and a secondary filter element are installed, and the primary filter element is installed on one side close to the liquid inlet of the filter device housing.

2. The energy-saving preparation device for high-purity phosphorus oxychloride according to claim 1, wherein, A sandwich layer is provided inside the mixing device, and a heating device is installed in the sandwich layer. A liquid inlet pipe is fixedly connected to the feed inlet of the mixing device, and a first regulating valve is installed on the liquid inlet pipe. An air inlet pipe is fixedly connected to the side wall of the liquid inlet pipe, and a second regulating valve is installed on the air inlet pipe. A first discharge pipe is installed at the discharge outlet of the mixing device, and a reflux pipe is fixedly connected to the bottom of the liquid inlet pipe.

3. The energy-saving preparation device for high-purity phosphorus oxychloride according to claim 2, wherein, The microchannel pipe is arranged in a ring shape, made of quartz material, with an inner diameter of 1 - 1.5 mm. One end of the first discharge pipe far from the mixing device is fixedly connected to the feed distribution pipe, and the bottom of the reflux collection pipe is fixedly connected to a second discharge pipe, on which a third regulating valve is installed.

4. The energy-saving preparation device for high-purity phosphorus oxychloride according to claim 3, characterized in that, The dynamic disperser includes a plurality of spiral guide vanes, which are fixedly connected to the inner side wall of the microchannel pipe in an interlaced manner. The plurality of spiral guide vanes are all arranged to incline downward in the direction of the medium flow. A plurality of micro through holes are provided on the side of the spiral guide vane close to the side wall of the microchannel pipe in a penetrating manner, and a plurality of micro grooves are provided on the upper surface of the side of the spiral guide vane far from the inner side wall of the microchannel pipe. The spacing of the spiral guide vanes is set to 5 - 10 mm, and the included angle between the inclination angle of the spiral guide vane and the central axis of the microchannel pipe is set to 30 - 60 degrees.

5. The energy-saving preparation device for high-purity phosphorus oxychloride according to claim 4, wherein, The condenser pipe includes a first housing and a second housing. The second housing is fixedly connected to the outside of the first housing, and a containing chamber is formed between the first housing and the second housing. The containing chamber is filled with a nano-phase change material. A fluid channel is provided inside the first housing, and a plurality of fins are fixedly connected to the outer side wall of the second housing. The first housing is made of graphite material, and the second housing and the fins are both made of copper alloy material.

6. The energy-saving preparation device for high-purity phosphorus oxychloride according to claim 5, characterized in that, A distributor is installed on one side close to the feed inlet inside the condenser housing. The inlet of the fluid channel of the first housing is communicated with the distributor. A collector is installed on one side close to the discharge outlet inside the condenser housing. The outlet of the fluid channel of the first housing is communicated with the collector. An exhaust pipe is installed on the collector, and the upper end of the exhaust pipe penetrates through the condenser housing and is located outside the condenser housing. A gas-liquid separator is installed at the upper end of the exhaust pipe.

7. A high-purity phosphorus oxychloride energy-saving preparation device according to claim 6, characterized in that, A return pipe is fixedly connected to the outer side wall of the feed inlet of the condenser housing. A fourth regulating valve is installed on the return pipe. The end of the return pipe away from the condenser housing is fixedly connected to the side wall of the second discharge pipe. The end of the reflux pipe away from the liquid inlet pipe is installed on the outer side wall of the liquid outlet of the condenser housing. An air delivery pipe is installed on the bottom side wall of the condenser housing. A fifth regulating valve is installed on the air delivery pipe. The end of the air inlet pipe away from the liquid inlet pipe is installed on the top side wall of the condenser housing.

8. The energy-saving preparation device for high-purity phosphorus oxychloride according to claim 7, characterized in that, The primary filter element is a sintered metal filter element with a pore size of 20 μm. The secondary filter element is a ceramic fiber filter membrane with a pore size of 5 μm. An inert gas delivery pipe is installed on one side of the filter device housing where the feed inlet is located. A backflush pipe is installed on one side of the filter device housing where the discharge outlet is located. The end of the liquid inlet pipe away from the mixing device is fixedly connected to the liquid outlet of the filter device housing.

9. A method for preparing high-purity phosphorus oxychloride with energy conservation, which is used in a device for preparing high-purity phosphorus oxychloride with energy conservation as described in any one of claims 1 to 8, characterized in that, The preparation method includes: S1. High-purity phosphorus trichloride is transported into the filter device housing through a liquid delivery pipe, and phosphorus trichloride is filtered by the primary filter element and the secondary filter element. At the same time, oxygen is transported into the condenser housing through the air delivery pipe, and the waste heat in the condenser housing is recovered and utilized by the oxygen. S2. The filtered phosphorus oxychloride is transported into the mixing device through the liquid inlet pipe, and the oxygen after absorbing heat is transported into the mixing device through the reflux pipe. In the mixing device, phosphorus oxychloride and oxygen are preliminarily mixed to obtain a reaction medium. S3. The reaction medium is transported into the feed distribution pipe through the first discharge pipe. The feed distribution pipe distributes the reaction medium to flow in multiple microchannel tubes. Under the action of the dynamic disperser in the microchannel tubes, microbubble dispersion of oxygen in the medium is achieved. Under the action of the microchannel tubes and the dynamic disperser, the reaction efficiency of phosphorus trichloride and oxygen is improved. The reaction medium in the microchannel tubes flows into the reflux collection pipe. S4. The reaction medium in the reflux collection pipe flows into the condenser housing through the return pipe. In the condenser housing, the waste heat in the reaction medium is absorbed by the condenser tube. The waste heat absorbed by the condenser tube is used for preheating the oxygen and compensating the heat of the reaction medium, so that the temperature of the reaction medium in the microchannel tubes is within the reaction range. S5. After the temperature of the reaction medium is adjusted in the condenser housing, it is transported into the mixing device through the reflux pipe, and then transported into the microchannel tubes through the mixing device for circulation. Phosphorus oxychloride is prepared by circulating and flowing in the microchannel tubes, and the prepared phosphorus oxychloride is discharged through the third regulating valve.

10. A method for energy-saving preparation of high-purity phosphorus oxychloride according to claim 9, characterized in that, The temperature of the reaction medium in the microchannel tubes is controlled at 50 - 80 °C, and the pressure of the reaction medium in the microchannel tubes is controlled at 0.1 - 0.3 MPa.

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