Gas-phase cold extraction and heavy component removal system and method in furan production through gas-phase furfural decarbonylation

Abstract

The invention discloses a gas-phase cold extraction and heavy component removal system in furan production through gas-phase furfural decarbonylation, which comprises: an extraction cold tower, the top of which is provided with a gas-phase outlet, the middle of which is provided with a gas-phase inlet, the upper part of which is provided with a liquid-phase inlet, the lower part of which is provided with a liquid-phase outlet, and the inside of which is provided with a stainless steel filler and a demister; and an outlet of the reaction cooler is connected with a gas phase inlet in the middle of the extraction cooling tower through a pipeline, a thermometer and a pressure gauge are arranged on the pipeline, and the reaction cooler takes circulating water as a cooling medium. In the process of decarbonylation of gas-phase furfural to furan production, a common cooling mode is not water-cooled or air-cooled because the gas-phase flow rate is relatively high. According to the invention, the cold extraction tower is additionally arranged, the temperature of a reaction gas phase can be easily reduced to about 15 DEG C by utilizing a furan vaporization cooling mode, the cooling effect is obvious, and furan is used as a final product without introducing other materials, so that the quality of the product is not influenced.

Description

Technical Field

[0001] This invention relates to the field of gas-phase furfural decarbonylation to furan production technology, and particularly to a gas-phase extraction cold degravimetric system and method for gas-phase furfural decarbonylation to furan production. Background Technology

[0002] In the industrial production of furfural to furan via decarbonylation in the gas phase, the post-reaction gas phase temperature is high, and some furfural remains unreacted, along with byproducts. If not separated promptly, this can lead to unnecessary waste of furfural, affect product purity, and cause compressor coking and damage, impacting production stability. Currently, commonly used separation methods in China are simple water or air cooling, which have low cooling efficiency and make precise temperature control difficult. Furthermore, in traditional cooling devices, insufficient contact between the reaction gas phase and the cooling medium results in poor cooling, increasing energy consumption and costs. In addition, incomplete separation of the cooled liquid phase from the reaction gas phase leads to furfural waste, increases the difficulty of subsequent product processing, and affects the stable operation of the compressor.

[0003] This device abandons the traditional water-cooling or air-cooling method and adds a cooling tower to cool down the furan by vaporization, condense the heavy components in the gas phase, and separate the unreacted furfural and the heavy components generated by the by-products. This avoids the heavy components from entering the compressor and affecting the stable operation of the compressor. At the same time, it can reduce the waste of furfural and the difficulty of subsequent product distillation. Summary of the Invention

[0004] To address the problems mentioned in the background section, this invention provides a gas-phase extraction and cold degravimetric system and method for the production of furfural from furfural.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A gas-phase extraction and cold degravimetric system for the production of furfural to furan via decarbonylation includes:

[0007] The evaporation tower is provided with a gas phase outlet at the top, a gas phase inlet in the middle, a liquid phase inlet at the top, a liquid phase inlet at the bottom, and a liquid phase outlet at the bottom. It is equipped with stainless steel packing and a demister inside.

[0008] The reaction cooler has its outlet connected to the gas phase inlet in the middle of the condensation tower via a pipe. The pipe is equipped with a thermometer and a pressure gauge, and the reaction cooler uses circulating water as the cooling medium.

[0009] The outlet cooler of the condensation tower has its inlet connected to the gas phase outlet at the top of the condensation tower via a pipeline, and its liquid phase outlet connected back to the condensation tower via a pipeline. The outlet cooler of the condensation tower uses zero-degree water as the cooling medium, and a thermometer is installed at its gas phase outlet.

[0010] The buffer tank's inlet is connected to the gas phase outlet of the cooling tower via a pipeline.

[0011] The furan cooler's outlet is connected to the upper liquid phase inlet of the continuous extraction cooling tower via a pipeline;

[0012] In addition, multiple regulating valves, flow meters, pressure gauges and level gauges are installed on the corresponding pipelines and equipment to control the operating parameters of the monitoring device;

[0013] The circulating pump, as well as the hot water inlet and outlet pipes.

[0014] Preferably, the hot water inlet pipe and the hot water outlet pipe are respectively connected to the bottom of the evaporation tower. The hot water inlet pipe is equipped with a regulating valve to control the hot water flow rate and regulate the temperature of the evaporation tower bottom. The circulating pump is used to promote the circulation of hot water.

[0015] Preferably, a precision flow meter and a regulating valve are installed on the furan feed pipe connected to the liquid phase inlet at the top of the evaporation tower;

[0016] The feed pipe of the furan cooler is also equipped with a precision flow meter and a regulating valve to control the furan feed rate and the degree of furan cooling, respectively.

[0017] Preferably, the stainless steel packing inside the evaporation tower is used to increase the gas-liquid contact area to enhance mass and heat exchange, and the demister is used to reduce liquid impurities entrained in the gas phase discharged from the top gas phase outlet of the evaporation tower.

[0018] Preferably, both the hot water inlet and outlet pipelines are connected to the bottom of the evaporation tower. The hot water heats the bottom of the evaporation tower, causing the light components in the bottom liquid to vaporize, while preventing the heavy components from agglomerating inside the tower.

[0019] Preferably, the condenser outlet cooler includes a shell-side inlet and a shell-side outlet, and the interior of the condenser outlet cooler is provided with a cooling water tube bundle. The top and bottom ends of the cooling water tube bundle are connected to distribution containers, and the two distribution containers are respectively connected with a cooling water inlet and a cooling water outlet. The cooling water inlet and the cooling water outlet extend to the outside of the condenser outlet cooler, and the interior of the condenser outlet cooler is provided with a condenser tube cleaning mechanism.

[0020] Preferably, the condenser tube cleaning mechanism includes a first cleaning blade holder and a first cleaning blade holder, both of which are fixed with multiple branches, and the branches are provided with arc-shaped grooves that correspond to and match the cooling water pipe bundle.

[0021] Preferably, the first cleaning blade holder and the first cleaning blade holder are driven to move up and down by a lifting drive mechanism. The lifting mechanism includes an upper fixed plate, a lower fixed plate and a lifting plate. A guide column and a reciprocating screw are installed between the upper fixed plate and the lower fixed plate. The guide column and the reciprocating screw pass through the lifting plate through a guide sleeve and a threaded sleeve, respectively. A driven bevel gear is fixed at the top of the reciprocating screw. A rotary motor is fixed on the outer wall of the cooler at the outlet of the condensation tower. A driving bevel gear is fixed on the output shaft of the rotary motor. The driven bevel gear and the driving bevel gear mesh with each other.

[0022] Preferably, a first mounting slide rail is fixed on the lifting plate, a first cleaning knife holder and a first cleaning knife holder are slidably mounted on the first mounting slide rail, a first wedge is fixed at the top and bottom of the first cleaning knife holder and the first cleaning knife holder, and a first trigger rod is fixed on the side of the upper fixing plate and the lower fixing plate that are close to each other.

[0023] A gas-phase quenching and heavy component removal method for furfural decarbonylation to furan includes the following steps: S1: The high-temperature reaction gas after the furfural decarbonylation reaction is introduced into a reaction cooler. After initial cooling by circulating water, it enters the quenching tower from the gas phase inlet in the middle of the quenching tower. A small amount of liquid phase in the reaction gas flows down along the surface of the stainless steel packing in the quenching tower to the bottom of the tower. The gas phase passes through the upper stainless steel packing under the pressure difference and comes into contact with the furan cooled by the furan cooler at the top of the quenching tower. The furan vaporizes and cools down, causing the furfural and heavy components of the by-products in the gas phase to condense into liquid. The condensate flows down along the surface of the packing to the bottom of the tower.

[0024] S2: Hot water is introduced into the bottom of the evaporation tower through the hot water inlet pipeline. The hot water flow rate is controlled by the regulating valve on the hot water inlet pipeline to regulate the temperature of the bottom of the tower, so that the light components in the bottom liquid are vaporized and rise, and exchange mass and heat with the downward liquid on the surface of the packing.

[0025] S3: The heavy components accumulated in the tower bottom are returned to the gas phase furfural decarbonylation reaction system for reuse of furfural; the gas phase at the top of the evaporation tower is introduced into the outlet cooler of the evaporation tower and cooled to 7-8°C by zero-degree water, so that more than 99.5% of furfural and by-products in the gas phase are condensed. The condensate is returned to the evaporation tower through a pipeline. The cooled gas phase enters the buffer tank and is then sent to the next process from the buffer tank.

[0026] Precision flow meters and regulating valves on the furan feed pipe and furan cooler feed pipe are used to accurately control the furan feed rate and cooling degree, ensuring stable temperature inside the condensation tower and effective separation of heavy components.

[0027] In the industrial production of furfural to furan via decarbonylation in the gas phase, the post-reaction gas phase temperature is high, and some furfural remains unreacted, along with byproducts. If not separated promptly, this can easily lead to furfural waste, affect product concentration, and cause compressor coking and damage, impacting production stability. Currently, commonly used separation methods in China are simple water or air cooling, which have low cooling efficiency and are difficult to control precisely. Furthermore, in traditional cooling devices, insufficient contact between the reaction gas phase and the cooling medium results in poor cooling, increasing energy consumption and costs. In addition, incomplete separation of the cooled liquid phase from the reaction gas phase also leads to furfural waste, increased difficulty in processing subsequent products, and a certain impact on the stable operation of the compressor.

[0028] The production of furfural to furan via gas-phase decarbonylation is a continuous process. The compressor, as a key piece of equipment for gas compression and transmission, is crucial. If heavy components from the reaction gas phase are not separated and enter the compressor, it can cause coking of the compressor valves, leading to compressor damage. Even with a backup compressor, compressor switching can cause production fluctuations, affecting system stability and even posing safety hazards. This invention addresses this by adding a cooling tower, utilizing furan vaporization for cooling, and controlling the temperature at the bottom of the cooling tower. This effectively separates unreacted furfural and byproducts from the reaction gas phase, reducing furfural waste and preventing heavy components from entering the compressor and causing valve coking damage. It also reduces compressor switching frequency, improves compressor operational stability, and ensures stable production.

[0029] Compared with the prior art, the beneficial effects of the present invention are:

[0030] 1. In the production of furfural to furan from gas phase carbonylation, common cooling methods include water cooling or air cooling. Because the gas phase flow rate is relatively high, the contact time between the reacting gas phase and the cooling medium in the cooler is insufficient, resulting in poor cooling effect and increased energy consumption and cost. In this invention, an extraction cooling tower is added, utilizing furan vaporization for cooling. This easily reduces the temperature of the reacting gas phase to approximately 15°C, demonstrating a significant cooling effect. Furthermore, since furan is the final product, no other materials are introduced, and it will not affect the quality of the product.

[0031] 2. In this invention, heating the bottom of the evaporation tower allows the light components in the liquid to vaporize and rise from the bottom. These vaporize and exchange mass and heat with the liquid flowing downwards, facilitating mass exchange on the packing surface. This achieves effective separation of the light and heavy components in the reaction gas phase. The heavy components continuously accumulate in the bottom of the evaporation tower and are eventually returned to the system via a regulating valve, enabling the reuse of furfural and saving costs. Furthermore, this invention uses hot water for heating, unlike the common use of steam. Hot water has a lower temperature and less temperature fluctuation compared to steam, preventing the heavy components from polymerizing in the bottom of the evaporation tower and ensuring a more stable temperature.

[0032] 3. In order to prevent some heavy components or liquid from remaining in the gas phase coming out of the evaporation tower, a cooler is installed at the outlet of the evaporation tower to cool it down with zero-degree water. After cooling, 99.5% of furfural and by-products in the reaction gas phase can be condensed and then returned to the evaporation tower, which can basically achieve complete separation of heavy components in the reaction gas phase. Attached Figure Description

[0033] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0034] Figure 1 This is a flowchart of the present invention;

[0035] Figure 2 This is a front view of the outlet cooler of the condenser tower according to the present invention;

[0036] Figure 3 This is a perspective sectional view of the outlet cooler of the condenser tower of the present invention;

[0037] Figure 4 This is a schematic diagram of the cooperation between the cooling water pipe bundle and the condenser pipe cleaning mechanism of the present invention;

[0038] Figure 5 This is a schematic diagram of the drive mechanism structure of the present invention;

[0039] Figure 6 This is a schematic diagram showing the cooperation relationship between the first wedge block and the first trigger rod of the present invention;

[0040] Figure 7 This is a schematic diagram of the first cleaning blade holder and the first cleaning blade holder's mating relationship according to the present invention;

[0041] Figure 8 This is a first-view perspective perspective view of the first cleaning blade holder of the present invention;

[0042] Figure 9 for Figure 8 Enlarged detail image of position A in the middle;

[0043] Figure 10 This is a second-view perspective perspective view of the first cleaning blade holder of the present invention;

[0044] Figure 11 for Figure 10 Enlarged detail image of position B in the middle;

[0045] In the diagram: 1. Cooling tower; 2. Reaction cooler; 3. Cooling tower outlet cooler; 301. Shell-side inlet; 302. Shell-side outlet; 303. Cooling water inlet; 304. Cooling water outlet; 4. Buffer tank; 5. Furan cooler; 6. Cooling water pipe bundle; 601. Distribution container; 7. First cleaning knife holder; 701. First cleaning knife holder; 702. Arc-shaped groove; 703. Positioning hole; 704. First wedge; 8. Lifting plate; 801. Upper fixed plate; 802. Lower fixed plate; 803. Reciprocating screw; 804. Guide column; 805. Driven bevel gear; 806. Rotary motor; 807. Driving bevel gear; 808. Second trigger rod; 809. First trigger rod; 9. First mounting slide rail; 901. Positioning plate; 902. Positioning pin; 903. Return spring; 904. Second wedge; 10. Second mounting slide rail. Detailed Implementation

[0046] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0047] Example 1

[0048] Reference Figure 1 A gas-phase extraction and cold degravimetric system for the production of furfural to furan via decarbonylation includes:

[0049] Cooling tower 1 has a gas phase outlet at the top, a gas phase inlet in the middle, a liquid phase inlet at the top, a liquid phase inlet at the bottom, and a liquid phase outlet at the bottom. It is equipped with stainless steel packing and a demister inside.

[0050] The outlet of the reaction cooler 2 is connected to the gas phase inlet in the middle of the condensation tower 1 through a pipeline. The pipeline is equipped with a thermometer and a pressure gauge, and the reaction cooler 2 uses circulating water as the cooling medium.

[0051] The outlet cooler 3 of the condensation tower has its inlet connected to the gas phase outlet at the top of the condensation tower 1 through a pipeline, and its liquid phase outlet connected back to the condensation tower 1 through a pipeline. The outlet cooler 3 of the condensation tower uses zero-degree water as the cooling medium, and a thermometer is installed at its gas phase outlet.

[0052] Buffer tank 4, whose inlet is connected to the gas phase outlet of the cooling tower 3 via a pipeline;

[0053] The outlet of the furan cooler 5 is connected to the upper liquid phase inlet of the continuous extraction cooling tower 1 via a pipeline;

[0054] In addition, multiple regulating valves, flow meters, pressure gauges and level gauges are installed on the corresponding pipelines and equipment to control the operating parameters of the monitoring device;

[0055] The circulating pump, as well as the hot water inlet and outlet pipes.

[0056] The hot water inlet pipe and the hot water outlet pipe are connected to the bottom of the condensation tower 1. A regulating valve is installed on the hot water inlet pipe to control the hot water flow rate and regulate the temperature of the bottom of the condensation tower 1. A circulating pump is used to promote the circulation of hot water.

[0057] Among them, the furan feed pipe connected to the upper liquid phase inlet of the evaporation tower 1 is equipped with a precision flow meter and a regulating valve;

[0058] The feed pipe of the furan cooler 5 is also equipped with a precision flow meter and a regulating valve to control the furan feed rate and the degree of furan cooling.

[0059] The stainless steel packing inside the condensation tower 1 is used to increase the gas-liquid contact area to enhance mass and heat exchange, and the demister is used to reduce liquid impurities entrained in the gas phase discharged from the top gas phase outlet of the condensation tower 1.

[0060] The hot water inlet and outlet pipelines are both connected to the bottom of the evaporation tower 1. The hot water heats the bottom of the evaporation tower 1, causing the light components in the bottom liquid to vaporize, while preventing the heavy components from polymerizing in the bottom of the tower.

[0061] Example 2

[0062] A gas-phase quenching and heavy component removal method for furfural decarbonylation to furan includes the following steps: S1: The high-temperature reaction gas after the furfural decarbonylation reaction is introduced into the reaction cooler 2. After initial cooling by circulating water, it enters the quenching tower 1 from the gas phase inlet in the middle of the quenching tower 1. A small amount of liquid phase in the reaction gas flows down along the surface of the stainless steel packing in the quenching tower 1 to the bottom of the tower. The gas phase passes through the upper stainless steel packing under the pressure difference and comes into contact with the furan cooled by the furan cooler 5 at the top of the quenching tower 1. The furan vaporizes and cools down, causing the furfural and heavy component of the by-products in the gas phase to condense into liquid. The condensate flows down along the surface of the packing to the bottom of the tower.

[0063] S2: Hot water is introduced into the bottom of the condensation tower 1 through the hot water inlet pipeline. The hot water flow rate is controlled by the regulating valve on the hot water inlet pipeline to regulate the bottom temperature, so that the light components in the bottom liquid are vaporized and rise, and exchange mass and heat with the downward liquid on the surface of the packing.

[0064] S3: The heavy components accumulated in the tower bottom are returned to the gas phase furfural decarbonylation reaction system for reuse of furfural; the gas phase at the top of the evaporation tower 1 is introduced into the outlet cooler 3 of the evaporation tower and cooled to 7-8°C by zero-degree water, so that more than 99.5% of the furfural and by-products in the gas phase are condensed. The condensate is returned to the evaporation tower 1 through the pipeline. The cooled gas phase enters the buffer tank 4 and is then sent to the next process from the buffer tank 4.

[0065] The feed rate and cooling level of furan are precisely controlled by the precision flow meter and regulating valve on the furan feed pipe and the feed pipe of furan cooler 5, so as to ensure the temperature stability and the separation effect of heavy components in the condensation tower 1.

[0066] Example 3

[0067] Reference Figure 2-11 The difference between this embodiment and embodiment 1 is that the condenser tower outlet cooler 3 includes a shell-side inlet 301 and a shell-side outlet 302, and the condenser tower outlet cooler 3 is provided with a cooling water tube bundle 6 inside. The top and bottom ends of the cooling water tube bundle 6 are connected to distribution containers 601, and the two distribution containers 601 are respectively connected to a cooling water inlet 303 and a cooling water outlet 304. The cooling water inlet 303 and the cooling water outlet 304 extend to the outside of the condenser tower outlet cooler 3, and the condenser tower outlet cooler 3 is provided with a condenser tube cleaning mechanism inside.

[0068] The condenser tube cleaning mechanism includes a first cleaning blade holder 7 and a first cleaning blade holder 701. Both the first cleaning blade holder 7 and the first cleaning blade holder 701 have multiple branches fixed on them, and the branches are provided with arc-shaped grooves 702 that correspond to and match the cooling water tube bundle 6. The first cleaning blade holder 7 and the first cleaning blade holder 701 cooperate to clamp the cooling water tube bundle 6 in the arc-shaped grooves 702. By moving the first cleaning blade holder 7 and the first cleaning blade holder 701 synchronously up and down, the dirt on the outer wall of the cooling water tube bundle 6 can be scraped off, thereby improving the heat exchange efficiency and the condensation effect.

[0069] The first cleaning blade holder 7 and the first cleaning blade holder 701 are driven to move up and down by a lifting drive mechanism. The lifting mechanism includes an upper fixed plate 801, a lower fixed plate 802 and a lifting plate 8. A guide column 804 and a reciprocating screw 803 are installed between the upper fixed plate 801 and the lower fixed plate 802. The guide column 804 and the reciprocating screw 803 pass through the lifting plate 8 through a guide sleeve and a threaded sleeve, respectively. A driven bevel gear 805 is fixed at the top of the reciprocating screw 803. A rotary motor 806 is fixed on the outer wall of the cooler 3 at the outlet of the evaporation tower. A driving bevel gear 807 is fixed on the output shaft of the rotary motor 806. The driven bevel gear 805 and the driving bevel gear 807 mesh with each other.

[0070] Turning on the rotary motor 806, the driven bevel gear 805 and the driving bevel gear 807 mesh with each other to drive the reciprocating screw 803 to rotate, which in turn drives the lifting plate 8 to move up and down, which in turn drives the first cleaning blade holder 7 and the first cleaning blade holder 701 to move up and down, and scrapes the scale off the outer wall of the cooling water pipe bundle 6.

[0071] A first mounting slide rail 10 is fixed on the lifting plate 8. The first cleaning knife holder 7 and the first cleaning knife holder 701 are slidably mounted on the first mounting slide rail 10. The top and bottom ends of the first cleaning knife holder 7 and the first cleaning knife holder 701 are both fixed with first wedge blocks 704. The upper fixing plate 801 and the lower fixing plate 802 are both fixed with first trigger rods 809 on the side that are close to each other.

[0072] When the lifting plate 8 moves up and down, when the first wedge 704 contacts the first trigger rod 809, it can push the first cleaning blade holder 7 and the first cleaning blade holder 701 to move horizontally. The first cleaning blade holder 7 and the first cleaning blade holder 701 move in opposite directions, so that each contact switches the distance between the first cleaning blade holder 7 and the first cleaning blade holder 701 between the maximum and minimum states. When the first cleaning blade holder 7 and the first cleaning blade holder 701 are close together, they can tightly clamp the cooling water pipe bundle 6, thereby improving the cleaning effect. When the first cleaning blade holder 7 and the first cleaning blade holder 701 separate when they are close together... It can be separated from the cooling water pipe bundle 6. When the lifting plate 8 moves upward so that the upper first wedge 704 contacts the first trigger rod 809, it switches to the state where the distance between the first cleaning blade holder 7 and the first cleaning blade holder 701 is the smallest. When the lifting plate 8 moves downward so that the lower first wedge 704 contacts the first trigger rod 809, it switches to the state where the distance between the first cleaning blade holder 7 and the first cleaning blade holder 701 is the largest. This ensures that scale is only scraped off when the first cleaning blade holder 7 and the first cleaning blade holder 701 move downward, so that the scale will only be scraped downward and fall to the bottom of the cooler 3 at the outlet of the condensation tower, which is convenient for subsequent flushing and discharge.

[0073] A positioning plate 901 is slidably mounted on the lifting plate 8 via the second mounting slide rail 10. A positioning pin 902 is fixed on the positioning plate 901, and a return spring 903 is connected between the positioning plate 901 and the first mounting slide rail 10. The positioning pin 902 passes through the first mounting slide rail 10. Two positioning holes 703 corresponding to the positioning pin 902 are opened on the first cleaning knife holder 7 and the first cleaning knife holder 701. A second wedge 904 is fixed on the side of the positioning plate 901 away from the positioning pin 902. The top and bottom of the second wedge 904 are provided with symmetrical inclined surfaces. A second trigger rod 808 is fixed on the side of the upper fixing plate 801 and the lower fixing plate 802 that are close to each other.

[0074] When the lifting plate 8 moves up and down, the second trigger rod 808 first contacts the second wedge 904 and pushes the positioning plate 901 to slide along the first mounting slide rail 10. At this time, the reset spring 903 is stretched, so that the positioning pin 902 is pulled out from the positioning hole 703 and continues to move. Only then will the distance between the first wedge 704 and the first trigger rod 809, the first cleaning blade holder 7 and the first cleaning blade holder 701 switch. Therefore, the locking will only be released when the lifting plate 8 moves up and down to near the highest and lowest states, so that the positions of the first cleaning blade holder 7 and the first cleaning blade holder 701 can be changed. During the up and down movement of the first cleaning blade holder 7 and the first cleaning blade holder 701, the distance between them is locked to ensure that the position will not change during cleaning.

[0075] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention 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. Therefore, they should not be construed as limitations on this invention.

[0076] In this invention, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," "link," and "fix" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, a direct connection, or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0077] The control method of this invention is automatic control through a controller. The control circuit of the controller can be implemented by simple programming by those skilled in the art. The power supply is also common knowledge in the art. Furthermore, since this invention is mainly used to protect mechanical devices, the control method and circuit connection will not be explained in detail here.

[0078] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A system for removing heavy components from a gas phase in the production of furan by decarboxylation of furfural in a gas phase, characterized in that It comprises: The extraction column (1) is provided with a gas phase outlet at the top, a gas phase inlet at the middle, a liquid phase inlet at the upper part, a liquid phase inlet at the lower part, a liquid phase outlet at the bottom, a stainless steel filler and a demister inside; The outlet of the reaction cooler (2) is connected to the middle gas phase inlet of the extraction column (1) through a pipeline, a thermometer and a pressure gauge are installed on the pipeline, and the reaction cooler (2) uses circulating water as the cooling medium; The inlet of the extraction column outlet cooler (3) is connected to the top gas phase outlet of the extraction column (1) through a pipeline, the liquid phase outlet is connected back to the extraction column (1) through a pipeline, the extraction column outlet cooler (3) uses zero-degree water as the cooling medium, and a thermometer is installed at the gas phase outlet; The inlet of the buffer tank (4) is connected to the gas phase outlet of the extraction column outlet cooler (3) through a pipeline; The outlet of the furan cooler (5) is connected to the upper liquid phase inlet of the extraction column (1) through a pipeline; A plurality of regulating valves, flow meters, pressure gauges and liquid level meters are respectively installed on the corresponding pipelines and equipment to control and monitor the operating parameters of the device; A circulating pump and hot water inlet and outlet pipelines.

2. The system for removing heavy components from the gas phase according to claim 1, characterized in that: The hot water inlet and outlet pipelines are respectively connected to the bottom of the extraction column (1), a regulating valve is installed on the hot water inlet pipeline to control the hot water flow and adjust the temperature of the extraction column (1) kettle, and the circulating pump is used to promote the circulation of hot water.

3. The system for removing heavy components from the gas phase according to claim 1, characterized in that: A precision flow meter and a regulating valve are installed on the furan inlet pipeline connected to the upper liquid phase inlet of the extraction column (1); A precision flow meter and a regulating valve are also installed on the furan cooler (5) inlet pipeline to control the furan feed amount and the furan cooling degree respectively.

4. The system for removing heavy components from the gas phase according to claim 1, characterized in that: The stainless steel filler in the extraction column (1) is used to increase the gas-liquid contact area to strengthen heat exchange, and the demister is used to reduce the liquid impurities entrained in the gas phase discharged from the top gas phase outlet of the extraction column (1).

5. The system for removing heavy components from the gas phase according to claim 1, characterized in that: The hot water inlet and outlet pipelines are both connected to the kettle of the extraction column (1), and the kettle is heated by hot water to make the light components in the kettle vaporize, while avoiding the polymerization of heavy components in the kettle.

6. The system for removing heavy components from the gas phase according to claim 1, wherein: The extraction column outlet cooler (3) comprises a shell inlet (301) and a shell outlet (302), and the inside of the extraction column outlet cooler (3) is provided with a cooling water pipe bundle (6), the top end and the bottom end of the cooling water pipe bundle (6) are connected with distribution containers (601), and the two distribution containers (601) are respectively connected with a cooling water inlet (303) and a cooling water outlet (304), the cooling water inlet (303) and the cooling water outlet (304) extend to the outside of the extraction column outlet cooler (3), and the inside of the extraction column outlet cooler (3) is provided with a condenser pipe cleaning mechanism.

7. The system for removing heavy components from the gas phase according to claim 6, characterized in that: The condenser pipe cleaning mechanism comprises a first cleaning knife holder (7) and a first cleaning knife holder (701), a plurality of branches are fixed on the first cleaning knife holder (7) and the first cleaning knife holder (701), and arc-shaped grooves (702) corresponding to the cooling water pipe bundle (6) are formed on the branches.

8. The system for removing heavy components from the gas phase according to claim 7, characterized in that: The first cleaning tool holder (7) and the first cleaning tool holder (701) drive the lifting movement by a lifting drive mechanism, the lifting mechanism comprises an upper fixed plate (801), a lower fixed plate (802) and a lifting plate (8), a guide column (804) and a reciprocating screw rod (803) are installed between the upper fixed plate (801) and the lower fixed plate (802), the guide column (804) and the reciprocating screw rod (803) penetrate the lifting plate (8) through a guide sleeve and a threaded sleeve respectively, and the top end of the reciprocating screw rod (803) is fixed with a driven bevel gear (805), a rotary motor (806) is fixed on the outer wall of the cold tower outlet cooler (3), the output shaft of the rotary motor (806) is fixed with a driving bevel gear (807), and the driven bevel gear (805) and the driving bevel gear (807) are meshed with each other.

9. The system for removing heavy components from the gas phase according to claim 8, characterized in that: The lifting plate (8) is fixed with a first mounting sliding rail (10), the first cleaning tool holder (7) and the first cleaning tool holder (701) are slidingly installed on the first mounting sliding rail (10), and the top end and the bottom end of the first cleaning tool holder (7) and the first cleaning tool holder (701) are fixed with first wedge blocks (704), and the side of the upper fixed plate (801) and the lower fixed plate (802) close to each other is fixed with a first trigger lever (809).

10. A method for removing heavy phase in the production of furan from furfural by decarboxylation in gas phase, by using a system for removing heavy phase in gas phase quenching as claimed in claims 1-9, characterized in that, The method comprises the following steps: S1: The high-temperature reaction gas after the gas-phase furfural decarbonylation reaction is introduced into the reaction cooler (2), and after being preliminarily cooled by circulating water, it is introduced into the extraction cold tower (1) from the middle gas-phase inlet of the extraction cold tower (1); a small amount of liquid phase in the reaction gas flows downward along the surface of the stainless steel filler in the extraction cold tower (1) to the tower kettle, and the gas phase passes through the upper layer of stainless steel filler under the push of the pressure difference, and contacts with furan cooled by the furan cooler (5) at the upper part of the extraction cold tower (1), so that the furfural and by-products in the gas phase are condensed into liquid by furan vaporization cooling, and the condensed liquid flows downward along the surface of the filler to the tower kettle; S2: hot water is introduced into the tower kettle of the extraction cold tower (1) through the hot water inlet pipeline, and the tower kettle temperature is adjusted by controlling the hot water flow through the adjusting valve on the hot water inlet pipeline, so that the light components in the kettle liquid are gasified and upward, and the downward liquid exchanges heat and mass with the upward gas on the surface of the filler; S3: the heavy components accumulated in the tower kettle are returned to the furfural decarbonylation reaction system for repeated use of furfural; the gas phase at the top of the extraction cold tower (1) is introduced into the extraction cold tower outlet cooler (3), and is cooled to 7-8 DEG C by zero-degree water, so that more than 99.5% of the furfural and by-products in the gas phase are condensed, the condensed liquid is connected back to the extraction cold tower (1) through the pipeline, and the cooled gas phase enters the buffer tank (4) and is then sent to the next process from the buffer tank (4); The furan inlet pipeline and the precise flow meter and adjusting valve on the furan cooler (5) inlet pipeline are used to accurately control the furan feeding amount and the cooling degree, so as to ensure the temperature stability in the extraction cold tower (1) and the separation effect of the heavy components.

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