Rectification system with multiple separation modules horizontally and flexibly arranged and gas-liquid reversely connected in series

Abstract

The invention discloses a multi-separation-module horizontal flexible layout and gas-liquid reverse series connection rectification system, which comprises a stripping unit and a rectification unit which are in multi-separation-module horizontal flexible layout and are in gas-liquid reverse series connection, as well as a feeding buffer unit, a condensation reflux unit and a reboiler unit. The rectification unit and the stripping unit are respectively composed of multi-stage separation modules with similar structures and can be horizontally and flexibly arranged according to an actual space; liquid passages among the multiple separation modules are driven by a pump, and the interior of each separation module drives gas-liquid countercurrent contact mass transfer through gravity; a gas-liquid two-phase heat and mass transfer runner structure is arranged in the separation module so as to vaporize light components in a liquid phase and condense heavy components in a gas phase. The separation modules are horizontally arranged, the layout can be adjusted according to the actual space, the overall height of the system is remarkably reduced while the space applicability is improved, and the device is suitable for material rectification separation in a height limiting scene.

Description

Technical Field

[0001] This invention relates to the field of chemical engineering, and in particular to a distillation system with a horizontally flexible layout of multiple separation modules and gas-liquid counter-current series connection. Background Technology

[0002] In chemical production, especially in the downstream production of green hydrogen, distillation columns are commonly used to purify and separate products, improving product precision. Currently, commonly used distillation columns are quite tall, generally exceeding 30 meters. In special production scenarios with height restrictions, such as offshore platforms, it is necessary to break down the distillation column into multiple units, significantly increasing the floor space required and process complexity. Therefore, a miniaturized design for distillation columns is needed.

[0003] Among existing distillation system technologies, one improved fractionation distillation tower system enhances separation efficiency and saves chiller power by using a plate-fin fractionation distiller. While this system utilizes a traditional plate-fin heat exchanger structure and achieves improved separation efficiency and chiller power savings, it does not optimize the tower's volume. Another technology, a marine exhaust-driven ammonia absorption chiller, replaces the distillation unit with a coil structure, allowing ammonia gas and ammonia water to flow in parallel thin tubes. This simplifies the distillation apparatus and makes the entire system compact, achieving miniaturization. However, marine exhaust-driven ammonia absorption chillers have low flow rates and are not suitable for large-scale chemical production.

[0004] In summary, current improvements to distillation columns for separating mixed gases mainly focus on increasing separation efficiency and reducing energy consumption. However, improvements to distillation columns for large-scale chemical production cannot adapt to the swaying conditions of offshore platforms simply by significantly reducing column volume and height. Furthermore, control methods for offshore floating chemical synthesis systems still need improvement.

[0005] Therefore, those skilled in the art are dedicated to providing a distillation system with a horizontally flexible layout of multiple separation modules and gas-liquid counter-current series connection, which reduces the overall system volume, achieves a compact system structure, and is applicable to scenarios such as offshore platforms with height restrictions. Summary of the Invention

[0006] In view of the deficiencies in the prior art, the technical problem to be solved by the present invention is how to provide a distillation system suitable for scenarios with height restrictions.

[0007] To achieve the above objectives, the present invention provides a distillation system with a horizontally flexible layout of multiple separation modules and a gas-liquid counter-current series configuration, comprising: The feeding buffer unit has a feeding end, a conveying end, and a return end; The distillation unit has a liquid phase input end, a liquid phase output end, a gas phase input end, and a gas phase output end. The liquid phase input end of the distillation unit is connected to the feed buffer unit's feed end, and the liquid phase and gas phase of the distillation unit flow in opposite directions. The reboiler unit has an input end, an output end and a reflux end. The input end of the reboiler unit is connected to the liquid phase output end of the stripping unit, the reflux end of the reboiler unit is connected to the gas phase input end of the stripping unit, and the output end of the reboiler unit outputs the separated and purified heavy component product. A distillation unit has a liquid phase input end, a liquid phase output end, a gas phase input end, and a gas phase output end. The gas phase input end of the distillation unit is connected to the gas phase output end of the stripping unit, and the liquid phase output end of the distillation unit is connected to the return end of the feed buffer unit. The liquid phase and gas phase of the distillation unit flow in opposite directions. The reflux condenser has an input end, an output end, and a reflux end. The input end of the reflux condenser is connected to the gas phase output end of the distillation unit, the reflux end of the reflux condenser is connected to the liquid phase input end of the distillation unit, and the output end of the reflux condenser outputs the separated and purified light component product.

[0008] Furthermore, the distillation unit includes at least two stages of distillation separation modules connected in series, the at least two stages of distillation separation modules being arranged horizontally; the liquid phase output terminal of the preceding stage distillation separation module is connected to the liquid phase input terminal of the following stage distillation separation module, and the gas phase input terminal of the preceding stage distillation separation module is connected to the gas phase output terminal of the following stage distillation separation module; the liquid phase input terminal and gas phase output terminal of the first stage distillation separation module are respectively the liquid phase input terminal and gas phase output terminal of the distillation unit, and the liquid phase output terminal and gas phase input terminal of the last stage distillation separation module are respectively the liquid phase output terminal and gas phase input terminal of the distillation unit.

[0009] Furthermore, the distillation separation module includes a distillation pump and a distillation separation unit, wherein the distillation pump is used to deliver liquid phase to the distillation separation unit.

[0010] Furthermore, the distillation and separation unit has a flow channel structure for gas-liquid two-phase heat and mass transfer, and gas-liquid countercurrent contact mass transfer is driven by gravity.

[0011] Preferably, the distillation and separation unit is one of a plate-fin structure, a coiled tube structure, or a packing structure, and achieves the vaporization of light components in the liquid phase and the condensation of heavy components in the gas phase by gravity drive.

[0012] Furthermore, the distillation unit includes at least two stages of distillation separation modules connected in series, the at least two stages of distillation separation modules being arranged horizontally; the liquid phase output terminal of the preceding stage distillation separation module is connected to the liquid phase input terminal of the following stage distillation separation module, and the gas phase input terminal of the preceding stage distillation separation module is connected to the gas phase output terminal of the following stage distillation separation module; the liquid phase input terminal and gas phase output terminal of the first stage stripping separation module are respectively the liquid phase input terminal and gas phase output terminal of the distillation unit, and the liquid phase output terminal and gas phase input terminal of the last stage distillation separation module are respectively the liquid phase output terminal and gas phase input terminal of the distillation unit.

[0013] Furthermore, the distillation separation module includes a distillation pump and a distillation separation unit, wherein the distillation pump is used to deliver liquid phase to the distillation separation unit.

[0014] Furthermore, the distillation separation unit has a flow channel structure for gas-liquid two-phase heat and mass transfer, and gas-liquid countercurrent contact mass transfer is driven by gravity.

[0015] Preferably, the distillation separation unit is one of a plate-fin structure, a coiled tube structure, or a packed structure, and achieves the vaporization of light components in the liquid phase and the condensation of heavy components in the gas phase by gravity drive.

[0016] Preferably, the feed at the feed end of the feed buffer unit is an azeotrope or a near-azeotrope.

[0017] The reboiler unit is also used to provide heat to the last stage of the distillation unit, causing the liquid produced by the distillation unit to partially vaporize and form a gas flow towards the next stage, thereby driving the component separation of the overall distillation system.

[0018] The reflux condenser is also used to cool the steam drawn from the top of the first-stage distillation unit, causing it to partially or completely condense into a liquid phase, thereby forming a reflux liquid and realizing the condensation and collection of the product; the reflux liquid is driven by a pump to form a liquid flow to the next stage, thereby driving the component separation of the entire distillation system.

[0019] The present invention has at least the following beneficial technical effects: The present invention provides a horizontally flexible distillation system with multiple separation modules connected in counter-current gas-liquid flow. The stripping and rectification units are each composed of multiple levels of structurally similar separation modules, and can be horizontally flexibly arranged according to actual space. The liquid passages between the multiple separation modules are driven by pumps, and the internal mass transfer of gas and liquid is driven by gravity through counter-current gas-liquid contact. The horizontally flexible layout significantly reduces the overall height of the system, making it suitable for material distillation and separation in height-restricted scenarios, and solving the problem that the height of the distillation device is not suitable for special production scenarios with height restrictions.

[0020] The following will further explain the concept, specific structure, and technical effects of the present invention in conjunction with the accompanying drawings, so as to fully understand the purpose, features, and effects of the present invention. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of a distillation system with a horizontally flexible layout of multiple separation modules and gas-liquid reverse series connection, according to an embodiment of the present invention.

[0022] In the diagram, 1-distillation unit, 2-rectification unit, 3-feed buffer unit, 4-condensation reflux unit, 5-reboiler unit, 6-rectification pump, 7-rectification separation unit. Detailed Implementation

[0023] The preferred embodiments of the present invention are described below to make the technical content clearer and easier to understand. The present invention can be embodied in many different forms, and the scope of protection of the present invention is not limited to the embodiments mentioned herein.

[0024] In the accompanying drawings, components with the same structure are indicated by the same numerical designation, and components with similar structures or functions are indicated by similar numerical designations. The dimensions and thicknesses of each component shown in the drawings are arbitrary, and the present invention does not limit the dimensions and thicknesses of each component. To make the illustrations clearer, the thickness of some components has been appropriately exaggerated in the drawings.

[0025] This invention provides a distillation system with multiple horizontally flexible separation modules connected in counter-current gas-liquid phases. The system includes a stripping unit and a rectification unit with multiple horizontally flexible separation modules connected in counter-current gas-liquid phases, as well as a feed buffer unit, a condenser reflux unit, and a reboiler unit. All separation modules are arranged horizontally and their layout can be adjusted according to the actual space. This improves the space applicability while significantly reducing the overall height of the system, making it suitable for material distillation and separation in height-restricted scenarios.

[0026] like Figure 1 As shown, the distillation system of this embodiment with multiple separation modules arranged horizontally and in counter-current gas-liquid phase has a feed buffer unit 3 with a feed end, a conveying end, and a return end. The feed end is used to input raw materials from the outside, and the return end is used to input the liquid phase separated from the distillation unit 2. The raw materials input from the outside and the liquid phase input from the distillation unit 2 are mixed in the feed buffer unit 3 and then conveyed to the lifting unit 1 from the conveying end.

[0027] The liquid phase inlet of stripping unit 1 is connected to the feed inlet of feed buffer unit 3 for inputting liquid phase; the liquid phase outlet of stripping unit 1 is connected to the inlet of reboiler unit 5 for supplying liquid phase to reboiler unit 5; the gas phase inlet of stripping unit 1 is connected to the outlet of reboiler unit 5 for receiving gas phase separated from reboiler unit 5; and the gas phase outlet of stripping unit 1 is connected to the gas phase inlet of rectification unit 2 for supplying gas phase to rectification unit 2. The liquid and gas phases flow countercurrently within stripping unit 1.

[0028] The distillation unit 1 includes multi-stage distillation and separation modules connected in series, such as two, three, or more stages. The liquid phase input and gas phase output of the first-stage distillation and separation module are the same as the liquid phase input and gas phase output of distillation unit 1. Similarly, the liquid phase output and gas phase input of the last-stage distillation and separation module are the same as the liquid phase output and gas phase input of distillation unit 1. The liquid phase output of the preceding stage distillation and separation module is connected to the liquid phase input of the following stage, and the gas phase input of the preceding stage distillation and separation module is connected to the gas phase output of the following stage, thus achieving countercurrent flow of the gas and liquid phases. The multi-stage distillation and separation modules are arranged horizontally and can be adjusted according to the actual space, significantly reducing the overall system height while improving spatial adaptability, making it suitable for material distillation and separation in height-restricted environments.

[0029] Each stage of the distillation and separation module includes a distillation pump and a distillation and separation unit. The distillation pump delivers liquid phase to the distillation and separation unit, enabling the liquid phase to flow between the distillation and separation modules. The distillation and separation unit has a flow channel structure for gas-liquid two-phase heat and mass transfer. Through gravity-driven countercurrent contact mass transfer of gas and liquid, it realizes the vaporization of light components in the liquid phase and the condensation of heavy components in the gas phase.

[0030] Specifically, the distillation and separation unit can adopt a plate-fin structure, a coiled tube structure, a packed structure, or other structures that can achieve the same separation effect.

[0031] The reboiler unit 5 has an input end and a reflux end, which are connected to the liquid phase input end and the gas phase input end of the stripping unit 1, respectively. The reboiler unit 5 provides heat to the last-stage stripping separation module, causing the liquid portion produced by the stripping unit 1 to vaporize and form a gas flow towards the next stage, thereby driving the component separation of the overall distillation system.

[0032] The reboiler unit 5 also has a discharge end for separating heavy components from the distillation system.

[0033] The liquid phase inlet of distillation unit 2 is connected to the reflux inlet of reflux condenser unit 4, for receiving liquid phase from reflux condenser unit 4; the liquid phase outlet of distillation unit 2 is connected to the feed return inlet of feed buffer unit 3, for supplying the separated liquid phase to feed buffer unit 3; the vapor phase inlet of distillation unit 2 is connected to the vapor phase outlet of stripping unit 1, for receiving vapor phase separated from stripping unit 1; the vapor phase outlet of distillation unit 2 is connected to the vapor phase inlet of reflux condenser unit 4, for supplying vapor phase to reflux condenser unit 4. The liquid and vapor phases flow countercurrently within distillation unit 2.

[0034] Distillation unit 2 also includes multi-stage distillation separation modules connected in series, such as two, three, or more stages. The liquid phase input and gas phase output of the first-stage distillation separation module are the same as the liquid phase input and gas phase output of distillation unit 2. Similarly, the liquid phase output and gas phase input of the last-stage distillation separation module are the same as the liquid phase output and gas phase input of distillation unit 2. The liquid phase output of the preceding distillation separation module is connected to the liquid phase input of the following distillation separation module, and the gas phase input of the preceding distillation separation module is connected to the gas phase output of the following distillation separation module, thus achieving countercurrent flow of the gas and liquid phases. The multi-stage distillation separation modules are also arranged horizontally and can be adjusted according to the actual space.

[0035] Each stage of the distillation separation module includes a distillation pump 6 and a distillation separation unit 7. The distillation pump 6 delivers liquid phase to the distillation separation unit 7, enabling the liquid phase to flow between the distillation separation modules. The distillation separation unit 7 also has a flow channel structure for gas-liquid two-phase heat and mass transfer. Through gravity-driven countercurrent contact mass transfer of gas and liquid, the vaporization of light components in the liquid phase and the condensation of heavy components in the gas phase are realized.

[0036] Similarly, the distillation separation unit 7 can adopt a plate-fin structure, a coiled tube structure, a packed structure, or other structures that can achieve the same separation effect.

[0037] The reflux condenser 4 has an input end and a reflux end, which are connected to the vapor phase output end and the liquid phase input end of the distillation unit 2, respectively. The reflux condenser 4 cools the vapor drawn from the top of the first-stage distillation separation module, causing it to partially or completely condense into a liquid phase, thereby forming a reflux liquid and realizing the condensation and collection of the product; the reflux liquid is driven by the distillation pump 6 to form a liquid flow in the direction of the next stage, thereby driving the component separation of the entire distillation system.

[0038] The condensation reflux unit 4 also has a discharge end for separating light components from the distillation system.

[0039] This invention uses the green hydrogen methanol synthesis process as an example and specifically discloses the following embodiments. After methanol synthesis, crude methanol needs to be separated to form high-purity methanol product and wastewater with extremely low methanol content. The distillation system of this invention can achieve effective separation.

[0040] Example 1

[0041] The crude methanol flow rate was 33,652 kg / h, of which 36.28 wt% was water and the remainder was methanol; the refined methanol flow rate after separation was 42,884 kg / h, with a methanol purity greater than 99.85%; the wastewater flow rate after separation was 24,450 kg / h, with a water purity greater than 99.99%.

[0042] The stripping unit 1 has two stripping separation modules, and the rectification unit 2 has three rectification separation modules. Both the stripping and rectification separation units adopt a plate-fin structure. The height of each separation module is less than 5m. By adopting a horizontal arrangement, the overall height of the device is less than 5m. The total area occupied by the stripping unit 1 and the rectification unit 2 is 100 square meters.

[0043] Example 2

[0044] The crude methanol flow rate was 33,652 kg / h, of which 36.28 wt% was water and the remainder was methanol; the refined methanol flow rate after separation was 42,884 kg / h, with a methanol purity greater than 99.85%; the wastewater flow rate after separation was 24,450 kg / h, with a water purity greater than 99.99%.

[0045] Unlike Example 1, both the stripping and rectification separation units adopt a packed structure. Each of the stripping unit 1 and the rectification unit 2 has two-stage separation modules. The height of each separation module is less than 6m. By adopting a horizontal arrangement, the overall height of the device is less than 6m. The total floor area of ​​the stripping unit 1 and the rectification unit 2 is 80 square meters.

[0046] Example 3

[0047] The crude methanol flow rate was 33,652 kg / h, of which 36.28 wt% was water and the remainder was methanol; the refined methanol flow rate after separation was 42,884 kg / h, with a methanol purity greater than 99.85%; the wastewater flow rate after separation was 24,450 kg / h, with a water purity greater than 99.99%.

[0048] Both the stripping and rectification separation units adopt a plate-fin structure.

[0049] Unlike Example 1, the stripping unit 1 has one separation module and the rectification unit 2 has two separation modules. Each separation module is less than 10m high. By adopting a horizontal arrangement, the overall height of the device is less than 10m. The total area occupied by the stripping unit 1 and the rectification unit 2 is 60 square meters.

[0050] In addition to the methanol / water mixture in the above embodiments, the distillation system of the present invention can also be used to separate other mixtures with similar separation characteristics, such as mixtures that form azeotropic or near-azeotropic systems, such as ethanol / water and acetone / water, all of which can be effectively separated.

[0051] This invention relates to a horizontally flexible, multi-separation module distillation system with counter-current gas-liquid flow, comprising a stripping unit and a rectification unit, as well as a feed buffer unit, a condenser / reflux unit, and a reboiler unit. Each of the rectification and stripping units consists of multiple stages of similarly structured separation modules, which can be flexibly arranged horizontally according to available space. The liquid pathways between the separation modules are driven by pumps, and gravity drives counter-current gas-liquid mass transfer within each module. Each separation module incorporates a flow channel structure for two-phase heat and mass transfer, enabling the vaporization of lighter components in the liquid phase and the condensation of heavier components in the gas phase. The separation modules are all horizontally arranged, and their layout can be adjusted according to available space, significantly reducing the overall system height while improving space adaptability, making it suitable for material distillation and separation in height-restricted environments.

[0052] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A distillation system with multiple horizontally flexible separation modules and gas-liquid counter-current series configuration, characterized in that, include: The feeding buffer unit has a feeding end, a conveying end, and a return end; The distillation unit has a liquid phase input end, a liquid phase output end, a gas phase input end, and a gas phase output end. The liquid phase input end of the distillation unit is connected to the feed buffer unit's feed end, and the liquid phase and gas phase of the distillation unit flow in opposite directions. The reboiler unit has an input end, an output end and a reflux end. The input end of the reboiler unit is connected to the liquid phase output end of the stripping unit, the reflux end of the reboiler unit is connected to the gas phase input end of the stripping unit, and the output end of the reboiler unit outputs the separated and purified heavy component product. A distillation unit has a liquid phase input end, a liquid phase output end, a gas phase input end, and a gas phase output end. The gas phase input end of the distillation unit is connected to the gas phase output end of the stripping unit, and the liquid phase output end of the distillation unit is connected to the return end of the feed buffer unit. The liquid phase and gas phase of the distillation unit flow in opposite directions. The reflux condenser has an input end, an output end, and a reflux end. The input end of the reflux condenser is connected to the gas phase output end of the distillation unit, the reflux end of the reflux condenser is connected to the liquid phase input end of the distillation unit, and the output end of the reflux condenser outputs the separated and purified light component product.

2. The distillation system with a horizontally flexible layout of multiple separation modules and counter-current gas-liquid separation as described in claim 1, characterized in that, The distillation unit includes at least two stages of distillation separation modules connected in series, the at least two stages of distillation separation modules being arranged in a horizontal direction; the liquid phase output terminal of the preceding stage distillation separation module is connected to the liquid phase input terminal of the following stage distillation separation module, and the gas phase input terminal of the preceding stage distillation separation module is connected to the gas phase output terminal of the following stage distillation separation module. The liquid phase input and gas phase output of the first-stage distillation and separation module are the liquid phase input and gas phase output of the distillation unit, respectively. The liquid phase output and gas phase input of the last-stage distillation and separation module are the liquid phase output and gas phase input of the distillation unit, respectively.

3. The distillation system with a horizontally flexible layout of multiple separation modules and counter-current gas-liquid separation as described in claim 2, characterized in that, The distillation and separation module includes a distillation pump and a distillation and separation unit, wherein the distillation pump is used to deliver liquid phase to the distillation and separation unit.

4. The distillation system with a horizontally flexible layout of multiple separation modules and counter-current gas-liquid separation as described in claim 3, characterized in that, The distillation and separation unit has a flow channel structure for gas-liquid two-phase heat and mass transfer, and gas-liquid countercurrent contact mass transfer is driven by gravity.

5. The distillation system with a horizontally flexible layout of multiple separation modules and counter-current gas-liquid separation as described in claim 4, characterized in that, The distillation and separation unit is one of the following: plate-fin structure, coiled tube structure, or packed structure.

6. The distillation system with a horizontally flexible layout of multiple separation modules and counter-current gas-liquid separation as described in claim 1, characterized in that, The distillation unit includes at least two distillation separation modules connected in series, the at least two distillation separation modules being arranged in a horizontal direction; the liquid phase output terminal of the preceding distillation separation module is connected to the liquid phase input terminal of the following distillation separation module, and the gas phase input terminal of the preceding distillation separation module is connected to the gas phase output terminal of the following distillation separation module. The liquid phase input and gas phase output of the first-stage distillation separation module are the liquid phase input and gas phase output of the distillation unit, respectively. The liquid phase output and gas phase input of the last-stage distillation separation module are the liquid phase output and gas phase input of the distillation unit, respectively.

7. The distillation system with a horizontally flexible layout of multiple separation modules and counter-current gas-liquid separation as described in claim 6, characterized in that, The distillation separation module includes a distillation pump and a distillation separation unit, wherein the distillation pump is used to deliver liquid phase to the distillation separation unit.

8. The distillation system with a horizontally flexible layout of multiple separation modules and counter-current gas-liquid separation as described in claim 7, characterized in that, The distillation and separation unit has a flow channel structure for gas-liquid two-phase heat and mass transfer, and gas-liquid countercurrent contact mass transfer is driven by gravity.

9. The distillation system with a horizontally flexible layout of multiple separation modules and counter-current gas-liquid separation as described in claim 8, characterized in that, The distillation separation unit is one of the following: plate-fin structure, coiled tube structure, or packed structure.

10. The distillation system with a horizontally flexible layout of multiple separation modules and counter-current gas-liquid separation as described in claim 1, characterized in that, The feed at the feed end of the feed buffer unit is an azeotrope or a near-azeotrope.

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