Green n-iso-butyl aldehyde separation system

Abstract

The utility model provides a kind of green normal iso-butylaldehyde separation system, the separation system includes atmospheric column, pressurized tower and splitter, and wherein the splitter is connected with the atmospheric column and the pressurized tower by atmospheric column raw material liquid entrance and pressurized tower raw material liquid entrance respectively.The utility model is through efficient heat recovery and unique pipeline design, significantly reduce energy consumption, improve separation efficiency, while reducing environmental pollution, realize the green separation of normal butylaldehyde and iso-butylaldehyde.Compared with prior art, the utility model has significant progress in energy saving and environmental protection, separation effect and system stability.

Description

Technical Field

[0001] This utility model belongs to the field of chemical production technology, specifically to a green isobutyraldehyde separation system. Background Technology

[0002] In the chemical production field, the separation of n-butyraldehyde and isobutyraldehyde is a key process, widely used in the synthetic resin, plastics, and fragrance industries. Traditional separation methods mainly rely on conventional distillation technology. However, due to the close boiling points of n-butyraldehyde and isobutyraldehyde, the separation process requires high energy input and has low efficiency, resulting in high production costs. Furthermore, the significant waste of heat energy during traditional distillation not only increases energy consumption but also exacerbates environmental pollution, contradicting the current trend of green chemistry. To address these issues, existing technologies have attempted to employ methods such as pressure distillation or azeotropic distillation. However, these methods often suffer from drawbacks such as complex equipment, high operational difficulty, high energy consumption, or the introduction of additional solvents leading to difficulties in subsequent processing. For example, while azeotropic distillation can improve separation efficiency, it requires the addition of an azeotropic agent, increasing the separation steps and potentially introducing new pollutants. Simple pressure distillation, while reducing the boiling point difference, places high demands on equipment and fails to effectively address the heat recovery problem. In recent years, heat recovery technology has gradually gained attention, but it still faces many challenges in practical applications, such as low pipeline heat transfer efficiency, insufficient insulation, and susceptibility to corrosion or scaling. Especially under high temperature and high pressure conditions, the durability and thermal stability of traditional pipelines often fail to meet long-term operational requirements. Furthermore, existing technologies lack a systematic solution for the comprehensive utilization of heat energy during the separation of n-butyraldehyde and isobutyraldehyde, resulting in low energy efficiency.

[0003] Therefore, developing a highly efficient, energy-saving, and environmentally friendly separation system for isobutyraldehyde has become a pressing technical challenge in this field.

[0004] In view of the above, this utility model is hereby proposed. Utility Model Content

[0005] The primary objective of this invention is to provide a green separation system for n- and isobutyraldehyde. Through efficient heat recovery and a unique pipeline design, it significantly reduces energy consumption, improves separation efficiency, and simultaneously reduces environmental pollution, achieving green separation of n-butyraldehyde and isobutyraldehyde. Compared with existing technologies, this invention represents a significant advancement in energy conservation, environmental protection, separation efficiency, and system stability.

[0006] In order to achieve the above-mentioned objectives of this utility model, the following technical solution is adopted:

[0007] A green isobutyraldehyde separation system includes an atmospheric pressure tower, a pressurized tower, and a distributor, wherein the distributor is connected to the atmospheric pressure tower and the pressurized tower respectively through the feed liquid inlet of the atmospheric pressure tower and the feed liquid inlet of the pressurized tower;

[0008] The atmospheric pressure tower is connected to the pressurized tower through a heat recovery system; the heat recovery system includes a heat recovery pipeline and an atmospheric pressure tower reboiler and a pressure control valve connected in sequence on the heat recovery pipeline. The atmospheric pressure tower reboiler is connected to the bottom of the atmospheric pressure tower, and the pressure control valve is connected to the top of the pressurized tower.

[0009] The heat recovery pipeline adopts a double-layer sleeve structure, with the inner pipe being a corrugated pipe and the outer pipe being an insulation jacket. The two ends of the outer pipe are connected to the reboiler and pressure control valve flange of the atmospheric pressure tower.

[0010] The space between the inner and outer pipes of the heat recovery pipeline is filled with inert gas.

[0011] This invention provides a green isobutyraldehyde separation system. Its core lies in achieving efficient heat energy utilization between the atmospheric and pressurized towers through a specific heat recovery system, thereby reducing energy consumption and improving separation efficiency. The separation system includes an atmospheric tower, a pressurized tower, and a distributor. The distributor separately delivers the feed liquid to the atmospheric and pressurized towers for separation. The heat recovery system transfers the steam heat energy from the top of the pressurized tower to the reboiler of the atmospheric tower through a double-layered heat recovery pipeline, achieving cascaded energy utilization. The heat recovery pipeline adopts a double-layered structure with an inner corrugated pipe and an outer insulated jacket, with inert gas filling the space between the inner and outer pipes. This design not only improves heat transfer efficiency but also increases... The system's stability and safety are enhanced. The inner wall of the corrugated pipe is coated with a hydrophobic-oleophilic composite coating, composed of nano-silica particles and fluorinated polymers. This coating effectively reduces fluid flow resistance and prevents scaling, while also improving affinity for organic matter, ensuring uniform and efficient heat transfer. In addition, thermally conductive ceramic particles are embedded in the troughs of the corrugated pipe, further enhancing its heat conduction performance. This allows heat to spread quickly and evenly within the pipe, preventing localized overheating or energy loss. The outer surface of the insulation jacket is covered with a removable reflective insulation layer, composed of multiple layers of aluminum foil and fiberglass cloth stacked alternately. This structure not only effectively reflects heat radiation and reduces heat loss but also facilitates maintenance and replacement, ensuring long-term insulation performance. The pressure control valve adopts an angle regulating valve with a double valve core structure inside. The upper valve core is connected to the steam outlet of the pressurized tower, and the lower valve core is connected to the reboiler of the atmospheric tower. This design can precisely regulate the steam flow and pressure, ensuring the stable operation of the heat recovery system and avoiding equipment damage or reduction in separation efficiency due to pressure fluctuations. Furthermore, the layout and connection method of the atmospheric and pressurized towers have been optimized in this invention. The top of the atmospheric tower has a discharge port and a reflux tank inlet. Both the condenser and the reflux tank are connected to the isobutyraldehyde storage tank, while the bottom of the tower is connected to the n-butyraldehyde storage tank and the reboiler through the discharge port, forming a closed-loop cycle to ensure efficient collection of separated products and continuous energy utilization. The top of the pressurized tower is connected to the pressure control valve through the steam outlet and is equipped with a buffer reflux tank to stabilize the system pressure. The bottom is connected to an external reboiler and connected to the n-butyraldehyde storage tank through the discharge port, further optimizing the thermodynamic efficiency of the separation process.

[0012] Overall, this invention's separation system achieves efficient, energy-saving, and green separation of n-butyraldehyde and isobutyraldehyde through heat recovery pipeline design, optimized tower layout, and precise pressure control. It solves the problems of high energy consumption, low efficiency, and severe environmental pollution in traditional separation technologies, demonstrating significant industrial application value and market prospects. Specifically, the system's double-layered heat recovery structure significantly improves thermal energy utilization, reduces external energy input, and lowers production costs. The application of hydrophobic-oleophilic coatings and thermally conductive ceramic particles further optimizes the heat transfer process, improving system stability and durability. The design of a detachable insulation layer and a dual-valve pressure control valve enhances system maintainability and operational flexibility, making it more adaptable to the needs of industrial production. Furthermore, the closed-loop circulation and energy cascade utilization design concept aligns with the development trend of green chemistry, reducing waste heat emissions and resource waste, and exhibiting significant environmental advantages.

[0013] Preferably, as a further feasible option, the inner wall of the corrugated pipe is coated with a hydrophobic-oleophilic composite coating, which is composed of nano-silica particles and fluorinated polymers, wherein the nano-silica particles have a particle size of 10-50 nm and the fluorinated polymers have a thickness of 0.5-2 μm.

[0014] This invention further defines the green isobutyraldehyde separation system, specifically involving a hydrophobic-oleophilic composite coating technology for the inner wall of a heat recovery pipeline. The coating is defined as being composed of nano-silica particles and a fluorinated polymer. The particle size of the nano-silica particles is controlled within the range of 10-50 nm, and the thickness of the fluorinated polymer is precisely controlled between 0.5-2 μm. The introduction of nano-silica particles first solves the industry problem of easy scaling and corrosion on the inner wall of traditional pipelines. Their nanoscale size endows the coating with an extremely high specific surface area and surface activity, enabling the formation of a rough structure at the microscale. This structure mimics the biomimetic principle of lotus leaf surfaces, giving the coating excellent hydrophobic properties and effectively preventing energy loss and corrosion risks caused by water vapor condensation on the pipe wall. Simultaneously, the addition of the fluorinated polymer not only acts as a binder for the nanoparticles, but its low surface energy further enhances the hydrophobic effect, forming a stable composite coating system.

[0015] More importantly, during the distillation process, the raw material liquid and steam contain a large number of organic components. The inner wall of traditional metal pipes has poor affinity for these substances, easily forming a stagnant layer that hinders heat transfer. The oleophilic properties of this invention are achieved through the molecular design of fluorinated polymers. The fluorinated segments can interact specifically with organic molecules, promoting the wetting and spreading of organic matter on the pipe wall, thereby significantly improving heat transfer efficiency. The particle size range of the nano-silica particles ensures sufficient surface roughness for superhydrophobic effects while avoiding the problems of uneven coating or reduced mechanical strength caused by excessively large particles. The fluorinated polymer thickness, controlled at 0.5-2 μm, balances the coating's durability and thermal resistance effect; too thin a layer would result in insufficient protection, while too thick a layer might affect heat conduction.

[0016] Furthermore, the coating technology of this invention solves several bottleneck problems in actual operation. First, under long-term high temperature and high pressure conditions, traditional coatings are prone to peeling and aging. However, this invention, through the synergistic effect of nanoparticles and polymers, gives the coating excellent heat resistance and mechanical stability. Second, in the phase change heat transfer process, the wetting characteristics of the pipe wall directly affect the condensation heat transfer coefficient. The hydrophobic-oleophilic intelligent design allows the droplets formed by steam condensation to quickly detach from the wall surface (hydrophobic effect), while organic matter can be evenly distributed on the wall surface to form a thin film (oleophilic effect). This dual mechanism improves heat transfer efficiency. Moreover, the anti-fouling properties of the coating significantly reduce the frequency of cleaning.

[0017] Preferably, as a further feasible option, thermally conductive ceramic particles are embedded in the troughs of the corrugated pipe of the heat recovery pipe.

[0018] This invention also embeds thermally conductive ceramic particles in the troughs of the corrugated pipe in the heat recovery pipeline. The corrugated pipe itself, due to its special waveform structure, already has better heat transfer characteristics than ordinary straight pipes. The alternating arrangement of its crests and troughs can effectively disrupt the laminar boundary layer of the fluid, promote turbulence formation, and thus enhance heat transfer efficiency. However, this invention further embeds thermally conductive ceramic particles in the troughs, thereby better breaking through the performance limits of traditional corrugated pipes and achieving a step-by-step improvement in heat transfer performance. The selection of thermally conductive ceramic particles in this invention is not arbitrary, but rather involves strict material screening. They typically have high thermal conductivity and excellent high-temperature stability and chemical inertness, making them particularly suitable for the corrosive environment that may occur during the separation of n-butyraldehyde and isobutyraldehyde. These particles are precisely embedded in the troughs. This specific location is based on the results of fluid dynamics simulation and experimental verification, because the troughs are areas with relatively low fluid velocity and high thermal resistance. Introducing high thermal conductivity materials in these areas can most effectively compensate for the weak points in heat transfer of traditional corrugated pipes.

[0019] Furthermore, in this invention, the embedding of thermally conductive ceramic particles forms a solid thermally conductive channel through direct contact between the particles and the metal pipe wall, and the extended heat transfer surface formed by the array of thermally conductive ceramic particles at the troughs; in addition, the fluid micro-disturbance effect caused by the gaps between the ceramic thermally conductive particles, these three mechanisms work together to fundamentally solve the problem of "thermal dead zones" existing in traditional corrugated pipes.

[0020] Preferably, as a further feasible option, the outer surface of the insulation jacket of the heat recovery pipe is covered with a removable reflective heat insulation layer, which is composed of multiple layers of aluminum foil and fiberglass cloth alternately stacked, with each layer of aluminum foil having a thickness of 0.1-0.3 mm and each layer of fiberglass cloth having a thickness of 0.5-1 mm.

[0021] This invention also defines the outer surface of the insulation jacket of the heat recovery pipeline. Specifically, the insulation layer is composed of multiple layers of aluminum foil and fiberglass cloth alternately laminated. The thickness of each aluminum foil layer is controlled at 0.1-0.3 mm, and the thickness of the fiberglass cloth is controlled at 0.5-1 mm. This multi-layered alternating structure combines the dual mechanisms of reflective and barrier insulation. The aluminum foil layer reflects a large amount of radiant heat through its high reflectivity, while the fiberglass cloth effectively blocks conductive heat through its low thermal conductivity. This synergistic effect makes the overall insulation performance far exceed that of traditional single-material insulation layers. More importantly, if the aluminum foil is too thin, it will result in insufficient mechanical strength and reduced reflectivity, while if it is too thick, it will increase unnecessary weight and cost. Similarly, the limited thickness of the fiberglass cloth ensures sufficient structural support and thermal resistance, while avoiding the problem of reduced flexibility caused by excessive thickness.

[0022] Preferably, as a further feasible option, the pressure control valve is an angle regulating valve with a double valve core structure inside the valve body. The upper valve core is connected to the steam outlet of the pressurized tower, and the lower valve core is connected to the reboiler of the atmospheric tower.

[0023] Furthermore, this utility model also specifies the specific structural design of the pressure control valve, which is an angle regulating valve with a double valve core structure inside the valve body. The upper valve core is connected to the steam outlet of the pressurized tower, and the lower valve core is connected to the reboiler of the atmospheric tower. Compared with the traditional straight-through regulating valve, the angle regulating valve can effectively reduce turbulence and pressure drop when the fluid passes through because its flow channel is a right angle turn, thereby reducing energy loss. In the isobutyraldehyde separation system, the steam generated at the top of the pressurized tower needs to be efficiently transferred to the reboiler of the atmospheric tower. The structure of the angle valve can ensure that the steam maintains high kinetic energy during the flow process and avoid steam condensation or pressure fluctuations caused by valve resistance.

[0024] Secondly, the upper valve core is connected to the steam outlet of the pressurized tower, responsible for regulating the steam flow and pressure; the lower valve core is connected to the reboiler in the atmospheric tower, used to control the heat transfer efficiency. This dual-valve core structure achieves coordinated control of pressure and heat, avoiding the insufficient control precision caused by the centralized function of a single valve core. In actual operation, the steam pressure of the pressurized tower may fluctuate due to changes in feed composition or operating conditions. The dual-valve core structure can quickly respond to these fluctuations by independently adjusting the opening of the upper and lower valve cores, ensuring the stability of the heat load of the reboiler in the atmospheric tower. For example, when the steam pressure increases, the upper valve core can be appropriately closed to reduce the flow, while the lower valve core adjusts its opening according to the actual needs of the reboiler, thereby maintaining the balance of heat transfer. This dynamic adjustment capability significantly improves the operational stability of the system, avoiding the temperature or pressure runaway caused by the adjustment lag of the traditional single-valve core structure. In addition, the dual-valve core structure also enhances the safety and fault tolerance of the system. In abnormal situations (such as a sudden increase in steam pressure or a sudden surge in reboiler heat load), the dual valve cores can work together to quickly cut off or restrict fluid flow, preventing overpressure or overheating of the equipment. For example, the upper valve core can quickly close when an abnormal pressure is detected, while the lower valve core adjusts its opening through feedback signals to ensure that the medium in the reboiler does not over-boil due to excessive heat input. This dual protection mechanism reduces the risk of system failure and extends the service life of the equipment. In addition, the modular design of the dual valve core structure facilitates maintenance and replacement. When one valve core becomes worn or clogged, it can be repaired separately without affecting the function of the other valve core, reducing downtime and maintenance costs.

[0025] Furthermore, the pressure control valve of this invention significantly improves the system's energy utilization efficiency. The steam at the top of the pressurized tower is rich in thermal energy, and direct discharge would result in enormous waste. Through the precise adjustment of the dual-valve-core pressure control valve, the steam's thermal energy is efficiently transferred to the reboiler in the atmospheric pressure tower, replacing traditional electric heating or external steam heating methods, thereby significantly reducing energy consumption. Particularly noteworthy is that the dual-valve-core structure can dynamically adjust the thermal energy input according to the actual needs of the atmospheric pressure tower, avoiding energy redundancy or insufficiency caused by excessive steam. For example, when the separation load is low, the lower valve core can reduce its opening to match the reboiler's requirements; while at high loads, the two valve cores work together to increase the steam flow, ensuring that separation efficiency is not affected. This adaptive adjustment capability allows the system to maintain optimal energy efficiency under different operating conditions, meeting the core requirements of green chemical engineering.

[0026] Preferably, as a further feasible option, the top of the atmospheric pressure tower is respectively provided with an atmospheric pressure tower outlet and a reflux tank inlet, the condenser is connected through the atmospheric pressure tower outlet, the reflux tank is connected to the atmospheric pressure tower through the reflux tank inlet, and both the reflux tank and the condenser are connected to the isobutyraldehyde storage tank; the bottom of the atmospheric pressure tower is provided with an atmospheric pressure tower outlet, the atmospheric pressure tower outlet is respectively connected to the n-butyraldehyde storage tank and the atmospheric pressure tower reboiler; the middle of the atmospheric pressure tower is provided with a feed liquid inlet, and the distributor is connected to the feed liquid inlet.

[0027] Preferably, as a further feasible option, the top of the pressurization tower is provided with a steam outlet and a buffer reflux tank inlet, the pressure control valve is connected to the steam outlet, and the buffer reflux tank is connected to the pressurization tower through the buffer reflux tank inlet.

[0028] Preferably, as a further feasible option, a circulation pipeline is provided between the reboiler of the atmospheric pressure column and the isobutyraldehyde storage tank, and the circulation pipeline is also connected to the buffer reflux tank.

[0029] Preferably, as a further feasible option, the bottom of the pressurized tower is also externally connected to a pressurized tower reboiler, and the bottom of the pressurized tower is also provided with a pressurized tower outlet, which is connected to the n-butyraldehyde storage tank.

[0030] The core components of the separation system of this utility model include an atmospheric pressure tower, a pressurized tower, a distributor, a heat recovery system, and related pipelines and storage tanks. The specific separation process is as follows: the raw material liquid is first divided into two streams by the distributor, which enter the atmospheric pressure tower and the pressurized tower respectively.

[0031] The splitter design ensures uniform flow distribution, laying the foundation for subsequent separation processes. The coordinated operation of the atmospheric and pressurized columns is key to achieving efficient separation. The atmospheric column operates at atmospheric pressure and is mainly used to separate isobutyraldehyde, which has a lower boiling point; the pressurized column operates under pressurized conditions and is used to separate n-butyraldehyde, which has a higher boiling point. The two columns are closely connected by a heat recovery system, enabling cascaded energy utilization.

[0032] The heat recovery system includes heat recovery piping, a reboiler in the atmospheric pressure tower, and a pressure control valve. The heat recovery piping employs a double-layered structure: an inner corrugated pipe and an outer insulating jacket, with an inert gas filling the space between them. This design not only improves heat transfer efficiency but also enhances system stability and safety. The inner wall of the corrugated pipe is coated with a hydrophobic-oleophilic composite coating composed of nano-silica particles and fluorinated polymers, effectively reducing fluid flow resistance and preventing scaling. Furthermore, thermally conductive ceramic particles are embedded in the troughs of the corrugated pipe, further enhancing heat conduction. The outer surface of the insulating jacket is covered with a removable reflective insulation layer, constructed from alternating layers of aluminum foil and fiberglass cloth, effectively reducing heat loss.

[0033] After the feed liquid enters the atmospheric distillation column, it is first distributed into the column through the feed inlet in the middle of the column. Then, the feed liquid is heated and vaporized by the atmospheric distillation reboiler in the bottom of the column. After vaporization, the feed liquid rises in the column and undergoes mass and heat transfer with the condensate flowing down from the top of the atmospheric distillation column. The isobutyraldehyde with a lower boiling point gradually rises to the top of the column. The top of the column is equipped with an atmospheric distillation column outlet and a reflux tank inlet. The vaporized isobutyraldehyde enters the condenser through the outlet and flows into the isobutyraldehyde storage tank after condensation. The reflux tank is connected to the condenser, and part of the condensate is returned to the column as condensate to ensure separation efficiency. The design of the reflux tank avoids unstable fluctuations of the components at the top of the column and improves the operational stability of the system.

[0034] At the bottom of the atmospheric distillation column, high-boiling-point n-butyraldehyde and other high-boiling-point components accumulate. The column has an outlet at the bottom, connected to both the n-butyraldehyde storage tank and the reboiler. A portion of the bottom liquid enters the reboiler, where heat recovery from the heat recovery system reheats the material before returning it to the column. This circular design ensures continuous utilization of heat within the column, reducing the need for external energy input. The remaining bottom liquid flows into the n-butyraldehyde storage tank as the n-butyraldehyde product, completing the separation process in the atmospheric distillation column.

[0035] Another stream of feed liquid enters the pressurized column and is separated under pressure. The operating pressure of the pressurized column is higher than that of the atmospheric column, which lowers the boiling point of n-butyraldehyde, making it easier to vaporize. The feed liquid entering the pressurized column is heated by the reboiler in the column bottom and gradually rises in the column. Mass and heat transfer occur after contacting the condenser flowing in from the top of the column. The top of the pressurized column is equipped with a steam outlet and a buffer reflux tank inlet. The vaporized isobutyraldehyde enters the heat recovery system through the steam outlet. The heat energy of the steam is used to heat the reboiler in the atmospheric column bottom. After condensation, most of the isobutyraldehyde flows into the isobutyraldehyde storage tank through the circulation pipeline, while a small portion flows into the buffer reflux tank. The buffer reflux tank is connected to the pressurized column, so a small portion of the isobutyraldehyde flows into the pressurized column as condensate for mass and heat transfer, thus achieving the separation of n- and isobutyraldehyde in the pressurized column.

[0036] The pressurized tower has a discharge port and an external reboiler at the bottom. A portion of the liquid at the bottom flows into the n-butyraldehyde storage tank through the discharge port. The reboiler provides additional heat energy through an external heat source (such as steam or electric heating) to ensure that the temperature at the bottom of the tower is maintained at the required level.

[0037] The heat recovery system serves as the link between the atmospheric and pressurized towers. Its core function is to transfer the heat energy of the steam at the top of the pressurized tower to the reboiler in the atmospheric tower via heat recovery pipes. The steam at the top of the pressurized tower first enters the heat recovery pipes through a pressure control valve. This pressure control valve is an angle regulating valve with a double-core structure. The upper valve core connects to the steam outlet of the pressurized tower, and the lower valve core connects to the reboiler in the atmospheric tower. This design allows for precise regulation of steam flow and pressure, ensuring efficient heat transfer. As steam flows through the heat recovery pipeline, its heat is efficiently transferred to the reboiler at the atmospheric pressure tower via the corrugated pipe and thermally conductive ceramic particles. The hydrophobic-oleophilic coating on the inner wall of the corrugated pipe reduces flow resistance and prevents scaling, while the thermally conductive ceramic particles further enhance heat conduction. The insulation jacket and reflective insulation layer effectively reduce heat loss, ensuring full utilization of heat energy. Finally, after releasing heat in the reboiler at the atmospheric pressure tower, the steam condenses, and the condensate returns to the pressurized tower or enters the isobutyraldehyde storage tank through the circulation pipeline, forming a closed-loop cycle.

[0038] Compared with traditional separation methods, the green separation system of this invention has significant advantages in energy conservation and environmental protection. Through the design of the heat recovery system, the system's thermal energy utilization rate is greatly improved, reducing the input of external energy. The application of hydrophobic-oleophilic coatings and thermally conductive ceramic particles optimizes the heat transfer process, further reducing energy consumption. Furthermore, the closed-loop design of the system reduces the emission of waste heat and waste liquid, aligning with the development trend of green chemical engineering.

[0039] In practical applications, this system can adapt to feed liquids with different compositions and flow rates, demonstrating excellent operational flexibility. For example, when the isobutyraldehyde content in the feed liquid is high, the load on the atmospheric distillation column increases, and the heat recovery system can dynamically adjust the heat energy distribution to ensure that the separation efficiency is not affected. This adaptive capability enables the system to maintain efficient and stable operation even under complex conditions.

[0040] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0041] (1) This utility model provides a green separation system for n- and isobutyraldehyde. Through efficient heat recovery and unique pipeline design, it significantly reduces energy consumption, improves separation efficiency, and reduces environmental pollution, thus achieving green separation of n-butyraldehyde and isobutyraldehyde. Compared with the prior art, this utility model has made significant progress in energy saving and environmental protection, separation effect and system stability. Attached Figure Description

[0042] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings.

[0043] Figure 1 This is a structural diagram of a green isobutyraldehyde separation system according to the present invention;

[0044] Figure 2 This is a cross-sectional view of the heat recovery pipeline in a green isobutyraldehyde separation system according to this utility model.

[0045] In the attached diagram:

[0046] 1. Feed inlet of atmospheric pressure column; 2. Reflux tank; 3. Condenser; 4. Atmospheric pressure column; 5. Buffer reflux tank; 6. Pressure control valve; 7. Isobutyraldehyde storage tank; 8. Pressurized column; 9. Pressurized column reboiler; 10. n-Butyraldehyde storage tank; 11. Atmospheric pressure column reboiler; 12. Diverter; 13. Removable reflective insulation layer; 14. Inert gas; 15. Bellows; 16. Thermally conductive ceramic particles. Detailed Implementation

[0047] The technical solution of this utility model will be clearly and completely described below with reference to the accompanying drawings and specific embodiments. However, those skilled in the art will understand that the embodiments described below are only some embodiments of this utility model, not all embodiments, and are only used to illustrate this utility model, and should not be regarded as limiting the scope of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall be followed. Where the manufacturers of reagents or instruments are not specified, they are all conventional products that can be purchased commercially.

[0048] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0049] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0050] To more clearly illustrate the technical solution of this utility model, the following description is provided in the form of specific embodiments.

[0051] Example 1

[0052] The specific separation process of the green isobutyraldehyde of this invention is as follows:

[0053] The feed liquid (a mixture of n-butyraldehyde and isobutyraldehyde) is first evenly divided into two streams by a splitter 12. 40% of the material enters the atmospheric column 4, and 60% enters the pressurized column 8. The splitter 12 delivers the first stream to the feed inlet in the middle of the atmospheric column 4 through the feed inlet 1 of the atmospheric column, and simultaneously delivers the second stream to the pressurized column 8 through the feed inlet of the pressurized column. The atmospheric column 4 operates at atmospheric pressure. The feed liquid is heated and vaporized in the reboiler at the bottom of the column and gradually rises to contact the condenser at the top of the column for mass and heat transfer. The vaporized isobutyraldehyde enters the condenser 3 through the outlet at the top of the column, and after condensation, flows into the isobutyraldehyde storage tank 7. The reflux tank 2 is connected to the condenser 3, and part of the condensate is returned to the atmospheric column 4 as condensate to ensure separation efficiency. The design of the reflux tank 2 avoids unstable fluctuations of the components at the top of the column and improves operational stability.

[0054] At the bottom of atmospheric column 4, high-boiling-point n-butyraldehyde and other high-boiling-point components accumulate. An atmospheric column outlet is located at the bottom of the column, connected to both the n-butyraldehyde storage tank 10 and the atmospheric column reboiler 11. Part of the bottom liquid enters the atmospheric column reboiler 11, is reheated by heat energy provided by the heat recovery system, and then returns to the column to maintain the bottom temperature. The other part of the bottom liquid flows into the n-butyraldehyde storage tank 10 as the n-butyraldehyde product. Pressurized column 8 operates under pressurized conditions, with the pressure set at an intermediate value to lower the boiling point of n-butyraldehyde, thus making it easier to... The material is easily vaporized. After being heated in the reboiler 9 of the pressurized tower, the material vaporizes and gradually rises in the tower. After mass and heat transfer with the condensate flowing down from the top of the tower, the vaporized isobutyraldehyde enters the heat recovery system through the steam outlet. Then, it flows into the atmospheric pressure tower reboiler 11 through the heat recovery pipeline for heat exchange. Afterward, most of the condensed isobutyraldehyde flows into the isobutyraldehyde storage tank 7 through the circulation pipeline, and a small part flows into the pressurized tower through the buffer reflux tank 5 connected to the pressurized tower 8 to act as a condenser for heat exchange.

[0055] The bottom of the pressurized tower 8 is equipped with a pressurized tower outlet and an external pressurized tower reboiler 9. The liquid at the bottom of the tower flows into the n-butyraldehyde storage tank 10 through the outlet for collection as high-purity n-butyraldehyde product. The pressurized tower reboiler 9 provides additional heat energy through an external heat source to ensure that the temperature at the bottom of the tower is maintained at the required level. The core of the heat recovery system of this utility model is to transfer the steam heat energy at the top of the pressurized tower 8 to the atmospheric pressure tower reboiler 11 through a heat recovery pipeline. The steam at the top of the pressurized tower 8 first enters the heat recovery pipeline through the pressure control valve 6. The pressure control valve 6 is an angle regulating valve with a double valve core structure inside the valve body. The upper valve core is connected to the steam outlet of the pressurized tower 8, and the lower valve core is connected to the atmospheric pressure tower reboiler 11. This design can accurately regulate the steam flow and pressure to ensure efficient heat energy transfer.

[0056] The heat recovery pipeline adopts a double-layer sleeve structure, with an inner corrugated pipe 15 and an outer insulation jacket, filled with an inert gas 14. The inner wall of the corrugated pipe 15 is coated with a hydrophobic-oleophilic composite coating, composed of nano-silica particles (10nm in diameter) and fluorinated polymers (0.5 μm thick), which effectively reduces fluid flow resistance and prevents scaling. Thermally conductive ceramic particles 16 are embedded in the troughs of the corrugated pipe 15, further enhancing the heat conduction performance. The outer surface of the insulation jacket is covered with a removable reflective insulation layer 13, which is composed of multiple layers of aluminum foil (0.1 mm thick) and fiberglass cloth (0.5 mm thick) alternately stacked, effectively reducing heat loss.

[0057] When steam flows in the heat recovery pipeline, its heat energy is efficiently transferred to the reboiler 11 of the atmospheric pressure tower through the bellows 15 and the thermally conductive ceramic particles 16. Finally, after releasing heat in the reboiler 11 of the atmospheric pressure tower, the steam condenses. The condensate is returned to the pressurized tower 8 or enters the isobutyraldehyde storage tank 7 through the circulation pipeline, forming a closed loop.

[0058] Example 2

[0059] The specific separation process of the green isobutyraldehyde of this invention is as follows:

[0060] The feed liquid (a mixture of n-butyraldehyde and isobutyraldehyde) is first evenly divided into two streams by a splitter 12. 50% of the material enters the atmospheric column 4, and 50% enters the pressurized column 8. The splitter 12 delivers the first stream to the feed inlet in the middle of the atmospheric column 4 through the feed inlet 1 of the atmospheric column, and simultaneously delivers the second stream to the pressurized column 8 through the feed inlet of the pressurized column. The atmospheric column 4 operates at atmospheric pressure. The feed liquid is heated and vaporized in the reboiler at the bottom of the column and gradually rises to contact the condenser at the top of the column for mass and heat transfer. The vaporized isobutyraldehyde enters the condenser 3 through the outlet at the top of the column, and after condensation, flows into the isobutyraldehyde storage tank 7. The reflux tank 2 is connected to the condenser 3, and part of the condensate is returned to the atmospheric column 4 as condensate to ensure separation efficiency. The design of the reflux tank 2 avoids unstable fluctuations of the components at the top of the column and improves operational stability.

[0061] At the bottom of atmospheric column 4, high-boiling-point n-butyraldehyde and other high-boiling-point components accumulate. An atmospheric column outlet is located at the bottom of the column, connected to both the n-butyraldehyde storage tank 10 and the atmospheric column reboiler 11. Part of the bottom liquid enters the atmospheric column reboiler 11, is reheated by heat energy provided by the heat recovery system, and then returns to the column to maintain the bottom temperature. The other part of the bottom liquid flows into the n-butyraldehyde storage tank 10 as the n-butyraldehyde product. Pressurized column 8 operates under pressurized conditions, with the pressure set at an intermediate value to lower the boiling point of n-butyraldehyde, thus making it easier to... The material is easily vaporized. After being heated in the reboiler 9 of the pressurized tower, the material vaporizes and gradually rises in the tower. After mass and heat transfer with the condensate flowing down from the top of the tower, the vaporized isobutyraldehyde enters the heat recovery system through the steam outlet. Then, it flows into the atmospheric pressure tower reboiler 11 through the heat recovery pipeline for heat exchange. Afterward, most of the condensed isobutyraldehyde flows into the isobutyraldehyde storage tank 7 through the circulation pipeline, and a small part flows into the pressurized tower through the buffer reflux tank 5 connected to the pressurized tower 8 to act as a condenser for heat exchange.

[0062] The bottom of the pressurized tower 8 is equipped with a pressurized tower outlet and an external pressurized tower reboiler 9. The liquid at the bottom of the tower flows into the n-butyraldehyde storage tank 10 through the outlet for collection as high-purity n-butyraldehyde product. The pressurized tower reboiler 9 provides additional heat energy through an external heat source to ensure that the temperature at the bottom of the tower is maintained at the required level. The core of the heat recovery system of this utility model is to transfer the steam heat energy at the top of the pressurized tower 8 to the atmospheric pressure tower reboiler 11 through a heat recovery pipeline. The steam at the top of the pressurized tower 8 first enters the heat recovery pipeline through the pressure control valve 6. The pressure control valve 6 is an angle regulating valve with a double valve core structure inside the valve body. The upper valve core is connected to the steam outlet of the pressurized tower 8, and the lower valve core is connected to the atmospheric pressure tower reboiler 11. This design can accurately regulate the steam flow and pressure to ensure efficient heat energy transfer.

[0063] The heat recovery pipeline adopts a double-layer sleeve structure, with an inner corrugated pipe 15 and an outer insulation jacket, filled with an inert gas 14. The inner wall of the corrugated pipe 15 is coated with a hydrophobic-oleophilic composite coating, composed of nano-silica particles (50nm in diameter) and fluorinated polymers (2μm thick), which effectively reduces fluid flow resistance and prevents scaling. Thermally conductive ceramic particles 16 are embedded in the troughs of the corrugated pipe 15, further enhancing the heat conduction performance. The outer surface of the insulation jacket is covered with a removable reflective insulation layer 13, which is composed of multiple layers of aluminum foil (0.3mm thick) and fiberglass cloth (1mm thick) alternately stacked, effectively reducing heat loss.

[0064] When steam flows in the heat recovery pipeline, its heat energy is efficiently transferred to the reboiler 11 of the atmospheric pressure tower through the bellows 15 and the thermally conductive ceramic particles 16. Finally, after releasing heat in the reboiler 11 of the atmospheric pressure tower, the steam condenses. The condensate is returned to the pressurized tower 8 or enters the isobutyraldehyde storage tank 7 through the circulation pipeline, forming a closed loop.

[0065] Example 3

[0066] The specific separation process of the green isobutyraldehyde of this invention is as follows:

[0067] The feed liquid (a mixture of n-butyraldehyde and isobutyraldehyde) is first evenly divided into two streams by a splitter 12. 40% of the material enters the atmospheric column 4, and 60% enters the pressurized column 8. The splitter 12 delivers the first stream to the feed inlet in the middle of the atmospheric column 4 through the feed inlet 1 of the atmospheric column, and simultaneously delivers the second stream to the pressurized column 8 through the feed inlet of the pressurized column. The atmospheric column 4 operates at atmospheric pressure. The feed liquid is heated and vaporized in the reboiler at the bottom of the column and gradually rises to contact the condenser at the top of the column for mass and heat transfer. The vaporized isobutyraldehyde enters the condenser 3 through the outlet at the top of the column, and after condensation, flows into the isobutyraldehyde storage tank 7. The reflux tank 2 is connected to the condenser 3, and part of the condensate is returned to the atmospheric column 4 as condensate to ensure separation efficiency. The design of the reflux tank 2 avoids unstable fluctuations of the components at the top of the column and improves operational stability.

[0068] At the bottom of atmospheric column 4, high-boiling-point n-butyraldehyde and other high-boiling-point components accumulate. An atmospheric column outlet is located at the bottom of the column, connected to both the n-butyraldehyde storage tank 10 and the atmospheric column reboiler 11. Part of the bottom liquid enters the atmospheric column reboiler 11, is reheated by heat energy provided by the heat recovery system, and then returns to the column to maintain the bottom temperature. The other part of the bottom liquid flows into the n-butyraldehyde storage tank 10 as the n-butyraldehyde product. Pressurized column 8 operates under pressurized conditions, with the pressure set at an intermediate value to lower the boiling point of n-butyraldehyde, thus making it easier to... The material is easily vaporized. After being heated in the reboiler 9 of the pressurized tower, the material vaporizes and gradually rises in the tower. After mass and heat transfer with the condensate flowing down from the top of the tower, the vaporized isobutyraldehyde enters the heat recovery system through the steam outlet. Then, it flows into the atmospheric pressure tower reboiler 11 through the heat recovery pipeline for heat exchange. Afterward, most of the condensed isobutyraldehyde flows into the isobutyraldehyde storage tank 7 through the circulation pipeline, and a small part flows into the pressurized tower through the buffer reflux tank 5 connected to the pressurized tower 8 to act as a condenser for heat exchange.

[0069] The bottom of the pressurized tower 8 is equipped with a pressurized tower outlet and an external pressurized tower reboiler 9. The liquid at the bottom of the tower flows into the n-butyraldehyde storage tank 10 through the outlet for collection as high-purity n-butyraldehyde product. The pressurized tower reboiler 9 provides additional heat energy through an external heat source to ensure that the temperature at the bottom of the tower is maintained at the required level. The core of the heat recovery system of this utility model is to transfer the steam heat energy at the top of the pressurized tower 8 to the atmospheric pressure tower reboiler 11 through a heat recovery pipeline. The steam at the top of the pressurized tower 8 first enters the heat recovery pipeline through the pressure control valve 6. The pressure control valve 6 is an angle regulating valve with a double valve core structure inside the valve body. The upper valve core is connected to the steam outlet of the pressurized tower 8, and the lower valve core is connected to the atmospheric pressure tower reboiler 11. This design can accurately regulate the steam flow and pressure to ensure efficient heat energy transfer.

[0070] The heat recovery pipeline adopts a double-layer sleeve structure, with an inner corrugated pipe 15 and an outer insulation jacket, filled with an inert gas 14. The inner wall of the corrugated pipe 15 is coated with a hydrophobic-oleophilic composite coating, composed of nano-silica particles (30nm in diameter) and fluorinated polymers (1.25 μm thick), which effectively reduces fluid flow resistance and prevents scaling. Thermally conductive ceramic particles 16 are embedded in the troughs of the corrugated pipe 15, further enhancing the heat conduction performance. The outer surface of the insulation jacket is covered with a removable reflective insulation layer 13, which is composed of multiple layers of aluminum foil (0.2mm thick) and fiberglass cloth (0.75mm thick) alternately stacked, effectively reducing heat loss.

[0071] When steam flows in the heat recovery pipeline, its heat energy is efficiently transferred to the reboiler 11 of the atmospheric pressure tower through the bellows 15 and the thermally conductive ceramic particles 16. Finally, after releasing heat in the reboiler 11 of the atmospheric pressure tower, the steam condenses. The condensate is returned to the pressurized tower 8 or enters the isobutyraldehyde storage tank 7 through the circulation pipeline, forming a closed loop.

[0072] Experiment Example 1: Performance Testing of a Green N-Isobutyraldehyde Separation System

[0073] Experimental objective: To verify the separation efficiency, energy consumption, and environmental performance of the green isobutyraldehyde separation system described in this invention in actual operation, and to compare it with traditional distillation technology;

[0074] Raw material solution: a mixture of n-butyraldehyde and isobutyraldehyde (mass ratio 1:1).

[0075] Testing instruments: Gas chromatograph (GC), flow meter, temperature sensor, pressure sensor, electricity meter;

[0076] Data collection:

[0077] Record the following parameters every 30 minutes:

[0078] Purity of the separated product (GC detection);

[0079] Energy consumption (the electricity meter records the additional heat input of the pressurized tower reboiler 9);

[0080] Heat recovery efficiency (calculated using temperature sensors to measure the heat transfer coefficient of the heat recovery pipe).

[0081] System stability (pressure fluctuation range);

[0082]

[0083] As can be seen from the above data, the green n- and isobutyraldehyde separation system provided by this utility model achieves efficient, energy-saving, and environmentally friendly separation of n-butyraldehyde and isobutyraldehyde through innovative structural design and process optimization. The core of the system consists of an atmospheric pressure tower, a pressurized tower, and a heat recovery system. Through a unique collaborative working mechanism, the separation performance is significantly improved. The three embodiments demonstrate the technical effects under different parameter configurations, with Embodiment 3 achieving the best overall performance by optimizing the parameters of key components.

[0084] First, the feed liquid is evenly distributed to the atmospheric distillation column and the pressurized distillation column via a distributor, forming a dual-column synergistic separation mode. The atmospheric distillation column preferentially separates isobutyraldehyde, which has a lower boiling point, under atmospheric pressure. The vaporized component at the top is condensed and purified before entering the isobutyraldehyde storage tank, while the high-boiling-point component at the bottom is either recycled through a reboiler or collected as n-butyraldehyde. The pressurized distillation column lowers the boiling point of n-butyraldehyde by increasing the operating pressure. The heat energy contained in the vapor at the top of the pressurized distillation column is transferred to the reboiler of the atmospheric distillation column through an innovative heat recovery system, achieving cascaded energy utilization. This design overcomes the bottleneck of low energy utilization in traditional distillation technology, forming a highly efficient energy closed loop.

[0085] The heat recovery system is the core technology of this invention. Its double-layered tube structure integrates multiple design features. The inner corrugated tube is coated with a nano-level hydrophobic-oleophilic composite coating, which prevents scaling and improves heat transfer efficiency. Thermally conductive ceramic particles embedded in the troughs further enhance heat conduction. Combined with a reflective insulation layer composed of 0.2mm aluminum foil and 0.75mm fiberglass cloth, the system's heat loss is minimized. The pressure control valve adopts a dual-valve core angle structure, which can precisely regulate steam flow and pressure, ensuring stable operation of the system within a minimal fluctuation range of ±2.4kPa.

[0086] Comparative experimental data from the three embodiments fully validated the technological advantages. Embodiment 3 demonstrated outstanding performance in key indicators: product purity reached 99.87% (n-butyraldehyde) and 99.83% (isobutyraldehyde), an improvement of 1.7-1.9% compared to traditional technologies; unit energy consumption was only 1.18 kWh / kg, achieving an energy saving rate of 52.2%; an 87.6% heat recovery rate enabled efficient energy recycling; the system could operate continuously and stably for 168 hours, extending the maintenance cycle by 133%; and the scaling rate was as low as 0.2 times / month, reducing production interruptions caused by shutdowns for cleaning. These performance breakthroughs are mainly attributed to: optimized coating parameters balancing hydrophobicity and heat transfer efficiency; a moderate insulation layer thickness ensuring insulation performance while avoiding bulky equipment; and a dual-valve core design perfectly solving the industry challenge of precise pressure control.

[0087] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.

Claims

1. A green n- isobutyraldehyde separation system, characterized by, It includes an atmospheric pressure tower, a pressurized tower, and a distributor, wherein the distributor is connected to the atmospheric pressure tower and the pressurized tower respectively through the feed liquid inlet of the atmospheric pressure tower and the feed liquid inlet of the pressurized tower; The atmospheric pressure tower is connected to the pressurized tower through a heat recovery system; the heat recovery system includes a heat recovery pipeline and an atmospheric pressure tower reboiler and a pressure control valve connected in sequence on the heat recovery pipeline. The atmospheric pressure tower reboiler is connected to the bottom of the atmospheric pressure tower, and the pressure control valve is connected to the top of the pressurized tower. The heat recovery pipeline adopts a double-layer sleeve structure, with the inner pipe being a corrugated pipe and the outer pipe being an insulation jacket. The two ends of the outer pipe are connected to the reboiler and pressure control valve flange of the atmospheric pressure tower. The space between the inner and outer pipes of the heat recovery pipeline is filled with inert gas.

2. The green n- isobutyraldehyde separation system of claim 1, wherein, The inner wall of the corrugated pipe is coated with a hydrophobic-oleophilic composite coating, which is composed of nano-silica particles and fluorinated polymers, wherein the nano-silica particles have a particle size of 10-50 nm and the fluorinated polymers have a thickness of 0.5-2 μm.

3. The green n- isobutyraldehyde separation system of claim 1, wherein, Thermally conductive ceramic particles are embedded in the troughs of the corrugated pipe of the heat recovery pipeline.

4. The green n- isobutyraldehyde separation system of claim 1, wherein, The heat recovery pipe has a removable reflective insulation layer on its outer surface, which is composed of multiple layers of aluminum foil and fiberglass cloth stacked alternately. The thickness of each layer of aluminum foil is 0.1-0.3 mm, and the thickness of each layer of fiberglass cloth is 0.5-1 mm.

5. The green n- isobutyraldehyde separation system of claim 1, wherein, The pressure control valve is an angle regulating valve with a double valve core structure inside the valve body. The upper valve core is connected to the steam outlet of the pressurized tower, and the lower valve core is connected to the reboiler of the atmospheric tower.

6. The green n- isobutyraldehyde separation system of claim 1, wherein, The atmospheric pressure column is provided with an atmospheric pressure column outlet and a reflux tank inlet at the top. The condenser is connected to the atmospheric pressure column outlet, and the reflux tank is connected to the atmospheric pressure column through the reflux tank inlet. Both the reflux tank and the condenser are connected to the isobutyraldehyde storage tank. The atmospheric pressure column is provided with an atmospheric pressure column outlet at the bottom, which is connected to the n-butyraldehyde storage tank and the atmospheric pressure column reboiler. The atmospheric pressure column is provided with a feed liquid inlet in the middle, and the distributor is connected to the feed liquid inlet.

7. The green n- isobutyraldehyde separation system of claim 1, wherein, The top of the pressurization tower is provided with a steam outlet and a buffer reflux tank inlet. The pressure control valve is connected to the steam outlet, and the buffer reflux tank is connected to the pressurization tower through the buffer reflux tank inlet.

8. The green n- isobutyraldehyde separation system of claim 6, wherein, A circulation pipeline is also provided between the reboiler of the atmospheric pressure tower and the isobutyraldehyde storage tank, and the circulation pipeline is also connected to the buffer reflux tank.

9. The green n- isobutyraldehyde separation system of claim 6, wherein, The bottom of the pressurizing tower is also externally connected to a reboiler, and the bottom of the pressurizing tower is also provided with a discharge port, which is connected to the n-butyraldehyde storage tank.

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