Rectification process and rectification device for high-purity nitrous oxide
Through the double-tower distillation process and improved tower plate combination block design, the problems of unstable nitrous oxide purity and high production cost were solved, and efficient nitrous oxide purification and stable production were achieved.
Patent Information
- Application Number
- CN202511188836.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-25
- Publication Date
- 2025-10-03
AI Technical Summary
In the existing nitrous oxide distillation process, the single-tower process results in unstable nitrous oxide purity, short contact time between liquid and gas phase materials, low separation rate, and increased production costs due to liquid phase retention.
A double-tower distillation process is adopted, through the combination of a heavy removal tower and a light removal tower, and a pump body is used to transport 99.5wt% of crude nitrous oxide. Combined with the temperature control of the reboiler and condenser, the separation of nitrous oxide from light and heavy components is achieved, and the contact time of the gas phase and liquid phase is extended through the improved tower plate combination block design.
The purity and stability of nitrous oxide are improved, the production cost is reduced, the working efficiency of the heavy removal tower and the light removal tower is improved, and the separation effect is enhanced.
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Figure CN120733374A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of chemical production, in particular to a distillation process and a distillation device for high-purity nitrous oxide. Background Art
[0002] With the development of the LED and semiconductor industries, the demand for high-purity nitrous oxide as an important raw material in the electronics industry is increasing, and higher purity requirements are required. The current industrial purification processes for nitrous oxide are mainly adsorption, filtration and distillation.
[0003] The industry mainly uses a single-tower process for the distillation of nitrous oxide. In actual operation, the gaseous nitrous oxide is condensed into liquid in the condenser of the distillation tower, and light component impurities flow out from the top of the tower. Some heavy component impurities will flow out with the liquid nitrous oxide, which will affect the purity of the nitrous oxide. The single-tower process is unstable for the removal of impurities from nitrous oxide.
[0004] The distillation tower plate assembly is the core component of the distillation tower. When the existing plate assembly is in use, the contact time between the liquid and gas phase materials is short, resulting in a low separation rate. In order to obtain a better separation effect, it is necessary to extend the contact time between the gas and liquid phase materials to improve the separation efficiency; and if too much liquid phase material flows in, it will be difficult for the liquid phase material to quickly pass through the sieve holes on the plate, which will cause part of the liquid phase material to remain on the plate for a long time. This phenomenon will cause material loss and greatly increase production costs. Summary of the Invention
[0005] In order to solve the above technical problems, the present invention provides a high-purity nitrous oxide distillation process and distillation device that reduce production costs and improve product precision.
[0006] The distillation process of high-purity nitrous oxide of the present invention comprises the following steps:
[0007] Step 1: Select crude nitrous oxide with a purity of 99.5 wt % and transport it to de-weighting column A under the transportation of a pump body. The feed rate of crude nitrous oxide is 600 kg / h, the feed temperature is 25 ° C, and the pressure is 20 bar;
[0008] Step 2: The hot side inlet temperature of the deweighting tower reboiler C is 40°C to -50°C, the hot side outlet temperature is 30°C to 40°C, the cold side inlet temperature of the deweighting tower condenser B is -30°C to -40°C, and the cold side outlet temperature is -20°C to -25°C;
[0009] Step 3: Most of the nitrous oxide and other light components are transported to the light component removal tower D through the No. 1 A outlet of the de-weighting tower condenser B and the No. 1 light component pipeline. A small part of the nitrous oxide and other light components are refluxed to the inside of the de-weighting tower A through the No. 1 B outlet of the de-weighting tower condenser B and the No. 1 B reflux pipeline.
[0010] Step 4, the hot side inlet temperature of the light removal tower reboiler F is 40°C to -50°C, the hot side outlet temperature of the light removal tower reboiler F is 30°C to 40°C, the cold side inlet temperature of the light removal tower condenser E is -30°C to -40°C, and the cold side outlet temperature of the light removal tower condenser E is -20°C to -25°C;
[0011] Step 5, nitrous oxide is separated from other light components, and the separated nitrous oxide enters the interior of the de-lightening tower condenser E for condensation, and most of the condensed nitrous oxide is discharged through the No. 2 A outlet on the de-lightening tower condenser E and the No. 2 light component pipeline, and a small part of the condensed nitrous oxide is refluxed to the interior of the de-lightening tower D through the No. 2 B outlet on the de-lightening tower condenser E and the No. 2 B reflux pipeline; a pump body is used to transport the crude nitrous oxide with a purity of 99.5wt% to the interior of the de-weighting tower A, and the de-weighting tower reboiler C heats the crude nitrous oxide inside the de-weighting tower A, and nitrous oxide, other light components and heavy components are separated inside the de-weighting tower A, and the gas After condensation in the de-heavy tower condenser B, the gaseous nitrous oxide and other light components enter the light-removing tower D through a pipeline. The condensed nitrous oxide and other light components are separated in the light-removing tower D. The separated gaseous nitrous oxide enters the light-removing tower condenser E for condensation. Most of the nitrous oxide is transported to the high-purity storage tank through the No. 2 A outlet on the light-removing tower condenser E and the No. 2 light component pipeline. A small part of the condensed nitrous oxide is refluxed to the light-removing tower D through the No. 2 B outlet on the light-removing tower condenser E and the No. 2 B reflux pipeline, thereby improving the working efficiency of the de-heavy tower A and the light-removing tower D, and at the same time improving the purity and stability of the nitrous oxide.
[0012] Preferably, in the step 1, the number of theoretical plates of the deweighting tower A is 50 to 60, the reflux ratio is 1 to 2, the top temperature is -17°C to -18°C, the bottom temperature is -17°C to -18°C, and the crude nitrous oxide feed position is at 54 to 60 plates.
[0013] Preferably, the number of theoretical plates of the light removal tower D in step 3 is 50 to 60, the reflux ratio is 30 to 40, the top temperature is -18°C to -19°C, the bottom temperature is -18°C to -19°C, and the feed position of nitrous oxide and other light components is at 3 to 9 plates.
[0014] A high-purity nitrous oxide distillation device comprises a de-weighting tower A, a de-weighting tower condenser B, a de-weighting tower reboiler C, a light-removing tower D, a light-removing tower condenser E, and a light-removing tower reboiler F. The top of the de-weighting tower A is connected to the de-weighting tower condenser B via a pipeline, an outlet No. A on the de-weighting tower condenser B is connected to the input end of the light component pipeline No. 1, an outlet No. B on the de-weighting tower condenser B is connected to the input end of the No. B reflux pipeline No. 1, and the output end of the No. B reflux pipeline is connected to the upper part of the de-weighting tower A. The kettle of the de-weighting tower A is connected to the de-weighting tower reboiler C via a pipeline, and the output end of the light component pipeline No. 1 is connected to the input end of the light-removing tower D.
[0015] The top of the light-removing tower D is connected to the light-removing tower condenser E through a pipeline, the No. 2 A outlet on the light-removing tower condenser E is connected to the No. 2 light component pipeline input end, the No. 2 B outlet on the light-removing tower condenser E is connected to the No. 2 B reflux pipeline input end, the No. 2 B reflux pipeline output end is connected to the upper part of the light-removing tower D, and the tower kettle of the light-removing tower D is connected to the light-removing tower reboiler F through a pipeline; the nitrous oxide gas raw material enters the heavy-removing tower A, enters the heavy-removing tower condenser B along the pipeline, and the nitrous oxide and other light components are transported to the light-removing tower D through the No. 1 A outlet of the heavy-removing tower condenser B and the No. 1 light component pipeline; the heavy component is condensed and passed through the No. 1 B outlet and the No. 1 B reflux pipeline on the heavy-removing tower condenser B. After entering the de-weighting tower A through the flow line, it flows along the pipeline into the de-weighting tower reboiler C, is heated into gas through the de-weighting tower reboiler C, and is repeatedly distilled and purified to remove the heavy component impurities in the nitrous oxide raw material to obtain a primary separation product. The heavy component impurities at the bottom of the de-weighting tower A are discharged through the sewage outlet, and the primary separation product enters the light component removal tower D, and is condensed through the light component removal tower condenser E. The light component impurities with a boiling point higher than that of nitrous oxide are transported to the high-purity storage tank through the No. 2 A outlet of the light component removal tower condenser E and the No. 2 light component pipeline. The crude nitrous oxide is refluxed into the light component removal tower D through the No. 2 B outlet and the No. 2 B reflux pipeline, is heated into gas through the light component removal tower reboiler F, and is repeatedly distilled and purified to obtain nitrous oxide liquid.
[0016] Preferably, the deweighting tower reboiler C is provided with a No. C outlet connected to the input end of the No. C reflux pipeline, and the output end of the No. C reflux pipeline is connected to the lower part of the deweighting tower A.
[0017] Preferably, the light removal tower reboiler F is provided with a No. 2 C outlet connected to the No. 2 C reflux line input end, and the output end of the No. 2 C reflux line is connected to the lower part of the light removal tower D.
[0018] Preferably, the heavy removal tower A and the light removal tower D both include multiple layers of tower sections, and a distillation tower plate assembly block is provided between two adjacent layers of tower sections.
[0019] Preferably, the distillation tower tray assembly block includes a tray, a triangular stopper, a fastener screw, an upper sieve hole and a lower sieve hole, the tray includes an upper sieve plate and a lower sieve plate, the upper sieve plate and the lower sieve plate are connected by fastener screws, the upper sieve plate is provided with a plurality of upper sieve holes, the aperture of the upper sieve holes gradually decreases from top to bottom along the upper sieve plate, the lower sieve plate is provided with a plurality of groups of lower sieve holes, the aperture of the lower sieve holes gradually increases from top to bottom along the lower sieve plate, the lower sieve plate is provided with a plurality of triangular stoppers, the axis of the upper sieve hole is aligned with the axis of the lower sieve hole The lines are staggered; the liquid in the distillation tower enters the interior of the tray through the upper sieve holes due to gravity. Several triangular blocks act as buffers, slowing down the forward speed of the liquid phase and prolonging the time for heat and mass exchange between the liquid and gas phases. Each tray is installed at an angle of 22.5 degrees to the horizontal plane, and the angle between adjacent trays is 45 degrees. This allows the liquid phase to flow from top to bottom by gravity without flowing too fast. In addition, the inclined tray can maximize the area for liquid phase flow and the time for gas phase to rise on the basis of the same floor space. The contact area of heat and mass exchange with the liquid phase, the triangular block is designed to be narrow at the top and wide at the bottom, which can not only slow down the flow rate of the liquid phase, but also prevent the liquid phase from being unable to flow down. According to the normal distribution, most of the liquid phase will flow to the large aperture position of the lower sieve plate, and then flow to the next level of tower plate, which will not cause some residual liquid phase materials to be unable to flow down, resulting in material waste. The aperture of the upper sieve hole gradually decreases from top to bottom, which is beneficial to the liquid phase to enter the interior of the tower plate smoothly and quickly. The aperture of the lower sieve hole gradually increases from top to bottom, which is beneficial to most of the liquid phase must flow through Multiple triangular blocks are required to enter the next level tower plate, delaying the time for the liquid phase to enter the tower plate and then enter the next level tower plate, thereby extending the heat and mass exchange time. Since the upper sieve holes and the lower sieve holes are arranged in an interlaced manner, the contact time between the gas and liquid phase materials is extended, thereby achieving better separation effect. At the same time, the number of tower plates in the distillation tower can be increased or decreased according to the properties of different materials, making it suitable for various production needs. The opening rate and diameter range of the tower plate can also be adjusted to avoid affecting the output due to the opening being too large or too small.
[0020] Preferably, the number of the tower plates is not less than four groups and the tower plates are staggered and stacked, with an angle of 45 degrees between two adjacent groups of tower plates and fixedly connected by welding, and an angle of 22.5 degrees between the tower plates and the horizontal.
[0021] Preferably, the outside of the upper sieve plate is fixedly connected to the outside of the lower sieve plate by welding, the upper sieve plate is provided with upper sieve screw holes, the lower sieve plate is provided with lower sieve screw holes, and the fastener screws are respectively threadedly connected to a group of lower sieve screw holes and a group of upper sieve screw holes.
[0022] Compared with the prior art, the present invention has the following beneficial effects: a pump body is selected to transport crude nitrous oxide with a purity of 99.5wt% to the interior of the de-weighting tower A, the de-weighting tower reboiler C heats the crude nitrous oxide in the de-weighting tower A, and nitrous oxide, other light components and heavy components are separated inside the de-weighting tower A. The gaseous nitrous oxide and other light components are condensed in the de-weighting tower condenser B and enter the interior of the de-weighting tower D through a pipeline. The condensed nitrous oxide and other light components are separated inside the de-weighting tower D, and the separated gaseous nitrous oxide enters the interior of the de-weighting tower condenser E for condensation. Most of the nitrous oxide is transported to a high-purity storage tank through the No. 2 A outlet on the de-weighting tower condenser E and the No. 2 light component pipeline, and a small part of the condensed nitrous oxide is refluxed to the interior of the de-weighting tower D through the No. 2 B outlet on the de-weighting tower condenser E and the No. 2 B reflux pipeline, thereby improving the working efficiency of the de-weighting tower A and the de-weighting tower D, and at the same time improving the purity and stability of the nitrous oxide. BRIEF DESCRIPTION OF THE DRAWINGS
[0023] Figure 1 It is a structural schematic diagram of the distillation device of the present invention;
[0024] Figure 2 It is a structural diagram of a distillation tower tray assembly block;
[0025] Figure 3 Schematic diagram of the top view of the upper sieve plate;
[0026] Figure 4 Schematic diagram of the top view of the lower sieve plate;
[0027] Figure 5 Schematic diagram of the top view of the tower plate shown.
[0028] Markings in the accompanying drawings: 1. tower plate; 2. upper sieve plate; 3. lower sieve plate; 4. triangular stopper; 5. fastener screw; 6. upper sieve hole; 7. screw hole of lower sieve plate; 8. lower sieve hole; 9. screw hole of upper sieve hole; 111. de-weighting tower A; 112. de-weighting tower condenser B; 113. de-weighting tower reboiler C; 114. de-lighting tower D; 115. de-lighting tower condenser E; 116. de-lighting tower reboiler F. DETAILED DESCRIPTION
[0029] To facilitate understanding of the present invention, the present invention will be described more fully below with reference to the accompanying drawings. The present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thorough and comprehensive.
[0030] Example 1
[0031] like Figure 1As shown, the distillation process and distillation device of the present invention for high-purity nitrous oxide have a crude nitrous oxide content of 99.5%, a feed flow rate of 600 kg / h, a feed temperature of 28° C., and a feed pressure of 20 bar.
[0032] The crude gaseous nitrous oxide is fed from the 55th tray of the de-weighting tower A111 at a reflux ratio of 1.2 for distillation. The top temperature of the de-weighting tower A111 is -17°C, and the bottom temperature is 35°C. The gas phase composition at the top of the tower is condensed by the de-weighting tower condenser B112. The heavy components are condensed into liquid phase and refluxed to the distillation tower at a flow rate of 700 kg / h. The light components in the gas phase are extracted from the top of the tower to the lightness removal tower D114 at a flow rate of 580 kg / h.
[0033] The gaseous light components are fed from the 5th tray of the de-lightness tower D114 with a reflux ratio of 35 for distillation. The top temperature of the de-lightness tower D114 is -17°C and the bottom temperature is 35°C. The top vapor of the de-lightness tower D114 is condensed by the de-lightness tower condenser E115, and a 99.99995% high-purity nitrous oxide product is extracted in the bottom of the tower and input into a high-purity storage tank.
[0034] After testing, the component contents of high-purity nitrous oxide are as follows:
[0035]
[0036]
[0037] Example 2
[0038] like Figure 1 As shown, the distillation process and distillation device of the present invention for producing high-purity nitrous oxide have a crude nitrous oxide content of 99.5%, a feed flow rate of 600 kg / h, a feed temperature of 28° C., and a feed pressure of 20 bar.
[0039] The crude gaseous nitrous oxide is fed from the 55th tray of the de-weighting tower A111 with a reflux ratio of 1.1 for distillation. The top temperature of the de-weighting tower A111 is -17°C and the bottom temperature is 35°C. The top vapor is condensed through the de-weighting tower condenser B112, and the heavy components are condensed into liquid and refluxed to the de-weighting tower A111 at a flow rate of 720 kg / h. The gaseous light components are extracted from the top of the tower to the de-weighting tower D114 at a flow rate of 650 kg / h.
[0040] The gaseous components are fed from the 5th tray of the de-lightness tower D114 with a reflux ratio of 37 for distillation. The top temperature of the de-lightness tower D114 is -17°C and the bottom temperature is 35°C. After the top vapor is condensed by the de-lightness tower reboiler F116, a 99.99995% high-purity nitrous oxide product is extracted from the bottom of the tower and input into a high-purity storage tank.
[0041] After testing, the component contents of high-purity nitrous oxide are as follows:
[0042]
[0043] Example 3
[0044] like Figures 1 to 5 As shown, the distillation process and distillation device of high-purity nitrous oxide of the present invention include a deweighting tower A111, a deweighting tower condenser B112, a deweighting tower reboiler C113, a light-removing tower D114, a light-removing tower condenser E115 and a light-removing tower reboiler F116. The top of the deweighting tower A111 is connected to the deweighting tower condenser B112 through a pipeline, the No. 1 A outlet on the deweighting tower condenser B112 is connected to the No. 1 light component pipeline input end, the No. 1 B outlet on the deweighting tower condenser B112 is connected to the No. 1 B reflux pipeline input end, the No. 1 B reflux pipeline output end is connected to the upper part of the deweighting tower A111, the tower bottom of the deweighting tower A111 is connected to the deweighting tower reboiler C113 through a pipeline, and the No. 1 light component pipeline output end is connected to the light-removing tower D114 input end.
[0045] The top of the lightness removal tower D114 is connected to the lightness removal tower condenser E115 through a pipeline, the No. 2 A outlet on the lightness removal tower condenser E115 is connected to the No. 2 light component pipeline input end, the No. 2 B outlet on the lightness removal tower condenser E115 is connected to the No. 2 B reflux pipeline input end, the No. 2 B reflux pipeline output end is connected to the upper part of the lightness removal tower D114, and the tower kettle of the lightness removal tower D114 is connected to the lightness removal tower reboiler F116 through a pipeline;
[0046] The de-weighting column reboiler C113 is provided with a No. C outlet connected to the input end of the No. C reflux pipeline, and the output end of the No. C reflux pipeline is connected to the lower part of the de-weighting column A111;
[0047] The light removal tower reboiler F116 is provided with a No. 2 C outlet connected to the input end of the No. 2 C reflux pipeline, and the output end of the No. 2 C reflux pipeline is connected to the lower part of the light removal tower D114;
[0048] The de-heavy tower A111 and the de-light tower D114 both include multiple layers of tower sections, with distillation tower plate assembly blocks provided between adjacent layers of tower sections;
[0049] The distillation tower tray assembly block includes a tray 1, a triangular stopper 4, a fastener screw 5, an upper sieve hole 6 and a lower sieve hole 8. The tray 1 includes an upper sieve plate 2 and a lower sieve plate 3, and the upper sieve plate 2 and the lower sieve plate 3 are connected by fastener screws 5. The upper sieve plate 2 is provided with a plurality of upper sieve holes 6, and the aperture of the upper sieve holes 6 gradually decreases from top to bottom along the upper sieve plate 2. The lower sieve plate 3 is provided with multiple groups of lower sieve holes 8, and the aperture of the lower sieve hole 8 gradually increases from top to bottom along the lower sieve plate 3. The lower sieve plate 3 is provided with a plurality of triangular stoppers 4, and the axis line of the upper sieve hole 6 is staggered with the axis line of the lower sieve hole 8;
[0050] The number of the tower plates 1 is not less than four groups and the tower plates 1 are staggered and stacked, with an angle of 45 degrees between two adjacent groups of tower plates 1 and fixedly connected by welding;
[0051] The outside of the upper sieve plate 2 is fixedly connected to the outside of the lower sieve plate 3 by welding. The upper sieve plate 2 is provided with upper sieve hole screw holes 9, and the lower sieve plate 3 is provided with lower sieve plate screw holes 7. The fastener screws 5 are threadedly connected with a group of lower sieve plate screw holes 7 and a group of upper sieve hole screw holes 9 respectively.
[0052] In this embodiment, the nitrous oxide gas raw material enters the de-weighting tower A111, and enters the de-weighting tower condenser B112 along the pipeline. Nitrous oxide and other light components are transported to the de-weighting tower D114 through the No. A outlet and the No. B light component pipeline of the de-weighting tower condenser B112; the heavy component is condensed and enters the de-weighting tower A111 through the No. B outlet and the No. B reflux pipeline on the de-weighting tower condenser B112, and then flows into the de-weighting tower reboiler C113 along the pipeline. It is heated into gas by the de-weighting tower reboiler C113, and is repeatedly distilled and purified to remove the heavy component impurities in the nitrous oxide raw material to obtain a primary separation product. The heavy component impurities at the bottom of the de-weighting tower A111 are discharged through the sewage outlet, and the first separation product enters the de-weighting tower. The light tower D114 is condensed by the light removal tower condenser E115, and the light component impurities with a boiling point higher than that of nitrous oxide are transported to the high-purity storage tank through the No. 2 A outlet of the light removal tower condenser E115 and the No. 2 light component pipeline. The crude nitrous oxide is refluxed to the light removal tower D114 through the No. 2 B outlet and the No. 2 B reflux pipeline, and is heated into gas by the light removal tower reboiler F116. It is repeatedly distilled and purified to obtain nitrous oxide liquid. The liquid in the heavy removal tower A111 or the light removal tower D114 enters the interior of the tower plate 1 through the upper sieve hole 6 due to gravity. Several triangular blocks 4 act as buffers to slow down the forward speed of the liquid phase material and prolong the time for heat and mass exchange between the liquid phase and the gas phase. Each tower plate 1 is connected to the water phase. The plane is installed with an inclination of 22.5 degrees, and the angle between adjacent tower plates 1 is 45 degrees, which can make the liquid phase flow from top to bottom by gravity without causing the flow speed to be too fast. In addition, the inclined tower plate 1 can also increase the area of liquid phase flow and the contact area of heat and mass exchange between the gas phase and the liquid phase when the gas phase rises as much as possible on the basis of the same floor space. The triangular block 4 is designed to be narrow at the top and wide at the bottom, which can slow down the flow speed of the liquid phase without preventing the liquid phase from flowing down. According to the normal distribution, most of the liquid phase will flow to the large aperture position of the lower sieve plate 3, and then flow to the next tower plate 1, which will not cause some residual liquid phase materials to be unable to flow down, resulting in material waste. The aperture of the upper sieve hole 6 gradually decreases from top to bottom, which is beneficial In order to ensure that the liquid phase enters the interior of the tower plate 1 smoothly and quickly, the aperture of the lower sieve hole 8 gradually increases from top to bottom, which is beneficial for most of the liquid phase to flow through multiple triangular blocks 4 before entering the next tower plate 1, so that the liquid phase does not enter the interior of the tower plate 1 directly and quickly into the next tower plate 1, which greatly prolongs the heat and mass exchange time. Since the upper sieve holes 6 and the lower sieve holes 8 are arranged in an interlaced manner, the contact time between the gas phase and the liquid phase materials is prolonged, thereby achieving better separation effect. At the same time, the number of tower plates in the distillation tower can be increased or decreased according to the properties of different materials, making it suitable for various production needs to change the single-tower distillation process into a double-tower distillation process, improve the purity of the nitrous oxide product, and ensure the stability of the product quality.
[0053] The installation, connection or setting methods of the high-purity nitrous oxide distillation process and distillation apparatus of the present invention are all common mechanical methods, and any method that can achieve its beneficial effects can be implemented; the deweighting tower A111 and the delightening tower D114 are both distillation towers; the deweighting tower condenser B112 and the delightening tower condenser E115 of the high-purity nitrous oxide distillation process and distillation apparatus of the present invention are purchased on the market, and technicians in the industry only need to install and operate them according to the accompanying instruction manuals, without the need for technical personnel in this field to expend creative labor.
[0054] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.
Claims
1. A distillation process for high-purity nitrous oxide, characterized in that: The following steps are involved: Step 1: Select crude nitrous oxide with a purity of 99.5 wt %, and transport it to deweighting column A (111) under the transportation of a pump body. The feed rate of crude nitrous oxide is 600 kg / h, the feed temperature is 25° C., and the pressure is 20 bar; Step 2: The hot side inlet temperature of the deweighting tower reboiler C (113) is 40°C to -50°C, the hot side outlet temperature is 30°C to 40°C, the cold side inlet temperature of the deweighting tower condenser B (112) is -30°C to -40°C, and the cold side outlet temperature is -20°C to -25°C; Step 3: Most of the nitrous oxide and other light components are transported to the de-weighting tower D (114) through the No. A outlet of the de-weighting tower condenser B (112) and the No. B light component pipeline. A small portion of the nitrous oxide and other light components are refluxed to the interior of the de-weighting tower A (111) through the No. B outlet of the de-weighting tower condenser B (112) and the No. B reflux pipeline. Step 4: The hot side inlet temperature of the de-lightness column reboiler F (116) is 40°C to -50°C, the hot side outlet temperature of the de-lightness column reboiler F (116) is 30°C to 40°C, the cold side inlet temperature of the de-lightness column condenser E (115) is -30°C to -40°C, and the cold side outlet temperature of the de-lightness column condenser E (115) is -20°C to -25°C; Step 5: Nitrous oxide is separated from other light components. The separated nitrous oxide enters the light component removal tower condenser E (115) for condensation. Most of the condensed nitrous oxide is discharged through the No. 2 A outlet on the light component removal tower condenser E (115) and the No. 2 light component pipeline. A small part of the condensed nitrous oxide is refluxed to the interior of the light component removal tower D (114) through the No. 2 B outlet on the light component removal tower condenser E (115) and the No. 2 B reflux pipeline.
2. The distillation process for high-purity nitrous oxide according to claim 1, wherein: In the step 1, the number of theoretical plates of the deweighting tower A (111) is 50 to 60, the reflux ratio is 1 to 2, the top temperature is -17°C to -18°C, the bottom temperature is -17°C to -18°C, and the crude nitrous oxide is fed at the 54th to 60th plate.
3. The distillation process for high-purity nitrous oxide according to claim 1, wherein: In the step 3, the light components removal tower D (114) has a theoretical plate number of 50 to 60, a reflux ratio of 30 to 40, a top temperature of -18°C to -19°C, a bottom temperature of -18°C to -19°C, and the feed position of nitrous oxide and other light components is at 3 to 9 plates.
4. A distillation device for high-purity nitrous oxide, characterized in that: The invention comprises a de-weighting tower A (111), a de-weighting tower condenser B (112), a de-weighting tower reboiler C (113), a de-weighting tower D (114), a de-weighting tower condenser E (115) and a de-lighting tower reboiler F (116), wherein the top of the de-weighting tower A (111) is connected to the de-weighting tower condenser B (112) through a pipeline, the No. A outlet on the de-weighting tower condenser B (112) is connected to the No. 1 light component pipeline input end, the No. B outlet on the de-weighting tower condenser B (112) is connected to the No. 1 B reflux pipeline input end, the No. 1 B reflux pipeline output end is connected to the upper part of the de-weighting tower A (111), the tower bottom of the de-weighting tower A (111) is connected to the de-weighting tower reboiler C (113) through a pipeline, and the No. 1 light component pipeline output end is connected to the light component tower D (114) input end. The top of the light-removal tower D (114) is connected to the light-removal tower condenser E (115) through a pipeline, the second A outlet on the light-removal tower condenser E (115) is connected to the input end of the second light component pipeline, the second B outlet on the light-removal tower condenser E (115) is connected to the input end of the second B reflux pipeline, and the output end of the second B reflux pipeline is connected to the upper part of the light-removal tower D (114), and the bottom of the light-removal tower D (114) is connected to the light-removal tower reboiler F (116) through a pipeline.
5. The high-purity nitrous oxide distillation device according to claim 4, characterized in that: The de-weighting tower reboiler C (113) is provided with a No. C outlet connected to the input end of the No. C reflux pipeline, and the output end of the No. C reflux pipeline is connected to the lower part of the de-weighting tower A (111).
6. The high-purity nitrous oxide distillation device according to claim 4, characterized in that: The light removal tower reboiler F (116) is provided with a No. 2 C outlet connected to the input end of the No. 2 C reflux pipeline, and the output end of the No. 2 C reflux pipeline is connected to the lower part of the light removal tower D (114).
7. The high-purity nitrous oxide distillation device according to claim 4, characterized in that: The deheaving tower A (111) and the delighting tower D (114) both include multiple layers of tower sections, and a distillation tower plate assembly block is provided between two adjacent layers of tower sections.
8. The high-purity nitrous oxide distillation device according to claim 7, characterized in that: The distillation tower plate assembly block comprises a plate (1), a triangular stopper (4), a fastener screw (5), an upper sieve hole (6) and a lower sieve hole (8); the plate (1) comprises an upper sieve plate (2) and a lower sieve plate (3); the upper sieve plate (2) and the lower sieve plate (3) are connected by the fastener screw (5); a plurality of upper sieve holes (6) are provided on the upper sieve plate (2); the aperture of the upper sieve holes (6) gradually decreases from top to bottom along the upper sieve plate (2); a plurality of groups of lower sieve holes (8) are provided on the lower sieve plate (3); the aperture of the lower sieve holes (8) gradually increases from top to bottom along the lower sieve plate (3); a plurality of triangular stoppers (4) are provided on the lower sieve plate (3); the axis of the upper sieve hole (6) and the axis of the lower sieve hole (8) are arranged in a staggered manner.
9. The high-purity nitrous oxide distillation device according to claim 8, characterized in that: The number of the tower plates (1) is not less than four groups, and the tower plates (1) are staggered and stacked. Two upper and lower adjacent tower plates (1) form an angle of 45 degrees and are fixedly connected by welding. The angle between the tower plates (1) and the horizontal is 22.5 degrees.
10. The high-purity nitrous oxide distillation device according to claim 8, characterized in that: The outer portion of the upper sieve plate (2) and the outer portion of the lower sieve plate (3) are fixedly connected by welding. Upper sieve hole screw holes (9) are provided on the upper sieve plate (2), and lower sieve plate screw holes (7) are provided on the lower sieve plate (3). Fastener screws (5) are respectively threadedly connected to a group of lower sieve plate screw holes (7) and a group of upper sieve hole screw holes (9).