Continuous loop reactor for gas-liquid-solid three-phase reaction and three-phase reaction method

Abstract

The present application relates to a continuous loop reactor for gas-liquid-solid three-phase reaction and a three-phase reaction method, the continuous loop reactor comprising a reaction kettle, a heat exchanger, a circulating pump and a Venturi gas-liquid ejector and being connected to form a loop, the upper part and the lower part of the reaction kettle being respectively provided with a feeding opening and a gas-liquid inlet, a product outlet and a gas phase outlet being arranged between the feeding opening and the gas-liquid inlet and the gas phase outlet being located above the product outlet, an annular flow channel being arranged at the product outlet, a hole being arranged in the side wall of the annular flow channel and being communicated with the reaction kettle, and a filter screen being arranged in the hole. The annular flow channel is arranged at the product outlet of the reaction kettle, the hole is arranged in the side wall of the annular flow channel and is communicated with the reaction kettle, and the filter screen is arranged in the hole, so that the solid catalyst can be blocked from flowing out with the liquid phase separation, the solid catalyst can be prevented from entering the circulating pump, and the reaction activity of the solid catalyst can be ensured.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of gas-liquid-solid multiphase reaction in chemical production, and particularly relates to a continuous loop reactor for gas-liquid-solid three-phase reaction. BACKGROUND

[0002] Gas-liquid-solid three-phase reaction is a common reaction in the field of chemical industry, and there are many types. In most cases, the solid is a catalyst, and the gas and liquid are reactants and products. Traditional loop reactors have good mass transfer effect, large external heat exchange area, good device sealing, and are widely used in gas-liquid two-phase reactions. There are many patent documents about loop reactors, for example: CN114011336A discloses a continuous production equipment and production method for biodiesel. The continuous production equipment adopts a jet loop reactor and a filter core pipe. The filter core pipe is composed of an inner pipe and an outer pipe of a tubular filter core. The bottom of the reaction kettle is connected with a heat exchanger through a circulating pump. The heat exchanger is connected with a venturi injector arranged at the top end of the reaction kettle through the inner pipe of the filter core pipe and a feed pipe. The venturi injector includes an inlet section, a nozzle, a mixing section and a diffusion section connected in sequence. The outer periphery of the inlet section and the nozzle is provided with a tapered annular gas chamber which is connected with the mixing section. The gas chamber is connected with the gas inlet arranged at the upper part of the reaction kettle through a gas circulation pipe. The feed pipe is provided with a feed inlet. The outer pipe of the filter core pipe is provided with a discharge outlet. CN215823085U discloses a loop reactor with high-efficiency venturi injector, which comprises a high-pressure reaction kettle, a loop circulating pump and a heat exchanger connected in sequence. The high-pressure reaction kettle is provided with a gas storage cavity and a gas-liquid storage cavity from top to bottom. The upper end of the high-pressure reaction kettle is provided with a venturi injector which is connected with the heat exchanger. The venturi injector comprises a gas chamber, a nozzle, a loop pipe, an air inlet pipe, a jet pipe and a mixing reaction pipe. The two ends of the jet pipe are connected with the gas chamber and the mixing reaction pipe respectively. The lower end of the mixing reaction pipe extends into the gas-liquid storage cavity. The gas chamber is arranged above the high-pressure reaction kettle. The nozzle is arranged in the gas chamber and opposite to the jet pipe. The gas chamber is also connected with the gas storage cavity through the loop pipe and connected with the air inlet pipe.

[0003] However, the dispersion effect of solid catalyst in the reaction kettle is poor, which is easy to mix into the circulating pump and is easy to be broken and deactivated under the high shear effect of the circulating pump, which limits the application of gas-liquid-solid three-phase reaction in the traditional loop reactor. SUMMARY

[0004] In view of the deficiencies and shortcomings in the prior art, the present application provides a continuous loop reactor for gas-liquid-solid three-phase reaction and a three-phase reaction method. The reactor can ensure the continuous progress of chemical reaction, uniform dispersion of gas-liquid-solid three-phase, avoid the solid catalyst entering the circulating pump, and ensure the reaction activity of the catalyst.

[0005] The technical scheme of the present application is as follows:

[0006] A continuous loop reactor for gas-liquid-solid three-phase reaction, comprising a reactor, a heat exchanger, a circulating pump and a Venturi gas-liquid ejector, the upper and lower parts of the reactor are respectively provided with a feeding port and a gas-liquid inlet, a product outlet and a gas phase outlet are arranged between the feeding port and the gas-liquid inlet, the gas phase outlet is above the product outlet, an annular flow channel is arranged at the product outlet, the side wall of the annular flow channel is provided with a hole communicating with the reactor, and a filter screen is arranged in the hole;

[0007] The product outlet of the reactor is connected with the liquid phase inlet of the Venturi gas-liquid ejector in sequence through the heat exchanger and the circulating pump, the gas phase outlet of the reactor is connected with the gas phase inlet of the Venturi gas-liquid ejector, and the gas-liquid outlet of the Venturi gas-liquid ejector is connected with the gas-liquid inlet of the reactor.

[0008] According to the application, preferably, the gas phase outlet of the reactor is further connected with a gas inlet valve. The gas raw material of the gas inlet valve and the separated gas phase of the gas phase outlet are jointly introduced into the gas phase inlet of the Venturi gas-liquid ejector.

[0009] According to the application, preferably, a product discharge valve is further arranged between the product outlet and the heat exchanger, for discharging the reaction product.

[0010] According to the application, preferably, a material inlet valve is further arranged between the heat exchanger and the circulating pump, for adding liquid reaction material into the reaction system.

[0011] According to the application, preferably, a porous baffle is further arranged in the reactor between the product outlet and the gas phase outlet, for separating the gas phase from the liquid phase in the reactor.

[0012] According to the application, preferably, the reactor is further provided with a scraper system composed of a servo motor, a transmission shaft and a scraper, the scraper is located at the same position as the filter screen of the annular flow channel, and the scraper is connected with the servo motor through the transmission shaft. The scraper is mainly used for removing the solid catalyst on the filter screen.

[0013] According to the application, preferably, an auxiliary function port is further arranged on the upper part of the reactor. The auxiliary function port can be used as a temperature measuring port, a pressure measuring port, a safety valve interface, an observation port, a liquid level meter installation port and the like.

[0014] According to the application, preferably, a check valve is further arranged between the gas-liquid inlet of the reactor and the gas-liquid outlet of the Venturi gas-liquid ejector; further preferably, an emptying valve is arranged between the check valve and the gas-liquid inlet of the reactor.

[0015] According to the application, preferably, the hole of the annular flow channel is in the shape of a sector;

[0016] Preferably, the maximum pore size of the filter screen is less than the average particle size of the solid catalyst.

[0017] According to the present application, preferably, the bottom of the annular flow channel is provided with a discharge port.

[0018] According to the present application, preferably, the reaction kettle is a cylindrical structure, and from the gas-liquid inlet to the feeding port, there are in sequence a catalyst suspension zone, a settling zone, and a gas phase zone, and the region of the annular flow channel is a solid phase separation zone; the catalyst suspension zone, the settling zone, and the solid phase separation zone are the main places for the gas-liquid-solid three-phase reaction.

[0019] Preferably, the diameter of the catalyst suspension zone is less than the diameter of the settling zone; that is, the catalyst suspension zone includes a variable-diameter zone and a small-diameter zone, and the settling zone is a large-diameter zone.

[0020] The present application also provides a method for carrying out a gas-liquid-solid three-phase reaction using the above continuous loop reactor, which comprises the following steps:

[0021] The solid catalyst is added into the reaction kettle through the feeding port, the gas raw material is fed into the gas phase inlet of the Venturi gas-liquid ejector through the gas inlet valve, the liquid raw material is fed into the circulating pump through the material inlet valve and then enters the liquid phase inlet of the Venturi gas-liquid ejector after being pressurized, the gas-liquid two-phase mixture is fed into the reaction kettle through the gas-liquid inlet after being mixed by the Venturi gas-liquid ejector, and the gas-liquid-solid three-phase reaction is carried out with the solid catalyst in the reaction kettle, the liquid phase product is discharged from the product outlet and is divided into two parts, one part of the product flows into the next process through the product discharge valve, and the other part of the product is mixed with the raw material supplemented through the material inlet valve after being heat-exchanged by the heat exchanger, is pressurized by the circulating pump, enters the liquid phase inlet of the Venturi gas-liquid ejector, and then enters the reaction kettle through the gas-liquid inlet to carry out continuous gas-liquid-solid three-phase loop reaction. Preferably, the flow rate of the raw material supplemented through the material inlet valve is the same as the flow rate of the product discharged through the product discharge valve.

[0022] The present application is provided with an annular flow channel at the product outlet of the reaction kettle, the side wall of the annular flow channel is provided with a hole and is in communication with the reaction kettle, a filter screen is arranged in the hole, the scraper system continuously removes the solid catalyst on the filter screen, the solid catalyst can be blocked from flowing out with the liquid phase separation, and thus the solid catalyst is prevented from entering the circulating pump, and the reaction activity of the solid catalyst is ensured. The multi-hole baffle is used for separating the gas phase and the liquid phase, and the liquid phase is prevented from entering the gas phase outlet. The reaction kettle, the heat exchanger, the circulating pump, and the Venturi gas-liquid ejector are connected to form a loop, which is very beneficial to the gas-liquid-solid three-phase loop reaction. At the same time, the material inlet valve continuously supplements the liquid raw material into the reaction system, the gas inlet valve continuously supplements the gas raw material into the system, and the product discharge valve continuously discharges a part of the reaction product, so that the gas-liquid-solid three-phase reaction is realized continuously.

[0023] The present application has the following beneficial effects:

[0024] 1、The present application is provided with annular flow channel at the product outlet of the reactor, the side wall of the annular flow channel is provided with hole and communicates with the reactor, the hole is provided with filter screen, which can prevent solid catalyst from flowing out with liquid phase separation, at the same time, the scraper system removes the solid catalyst on the filter screen constantly, further avoids the solid catalyst flowing out of the reactor, and avoids the solid catalyst entering the circulating pump, thereby ensuring the reaction activity of the solid catalyst.

[0025] 2、The diameter of the catalyst suspension zone of the reactor of the present application is smaller than the diameter of the settling zone, that is, the diameter of the reactor increases from bottom to top. Not only can the gas-liquid-solid three-phase be uniformly dispersed in the catalyst suspension zone, but also the settling of the solid catalyst is more conducive in the settling zone, which has certain effect on preventing the solid catalyst from entering the liquid phase outlet.

[0026] 3、The present application connects the reactor, heat exchanger, circulating pump and venturi gas-liquid ejector to form a circulating loop, which is very beneficial to the gas-liquid-solid three-phase reaction. At the same time, the material inlet valve constantly supplements the liquid raw material into the reaction system, the gas inlet valve constantly supplements the gas raw material into the system, and the product discharge valve constantly discharges part of the reaction product, so that the gas-liquid-solid three-phase reaction is realized continuously. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 It is the main structure schematic diagram of the continuous loop reactor of the gas-liquid-solid three-phase reaction of the present application.

[0028] Figure 2 It is the main structure schematic diagram of the reactor in the continuous loop reactor of the gas-liquid-solid three-phase reaction of the present application.

[0029] Figure 3 It is the main structure schematic diagram of the annular flow channel in the continuous loop reactor of the gas-liquid-solid three-phase reaction of the present application.

[0030] Figure 4 It is the interface schematic diagram of the venturi gas-liquid ejector in the continuous loop reactor of the gas-liquid-solid three-phase reaction of the present application.

[0031] Among them: 1-reaction kettle, 2-product discharge valve, 3-heat exchanger, 4-material inlet valve, 5-circulating pump, 6-venturi gas-liquid ejector, 7-check valve, 8-emptying valve, 9-gas inlet valve, 100-servo motor, 101-transmission shaft, 102-scraper, 11-assisted function port, 12-feeding port, 13-perforated baffle, 14-annular flow channel, 15-product outlet, 16-filter screen, 17-discharge port, 18-gas-liquid inlet, 19-gas phase outlet, 41-gas-liquid outlet, 42-gas phase inlet, 43-liquid phase inlet, I-catalyst suspension zone, II-settling zone, III-solid phase separation zone, IV-gas phase zone. DETAILED DESCRIPTION

[0032] The present invention will be further described below with reference to specific embodiments and accompanying drawings, but is not limited thereto.

[0033] Example 1

[0034] like Figures 1-4 As shown, a continuous loop reactor for a gas-liquid-solid three-phase reaction includes a reactor 1, a heat exchanger 3, a circulating pump 5, and a Venturi gas-liquid ejector 6. The reactor 1 is provided with a feed port 12 and a gas-liquid inlet 18 at its upper and lower parts, respectively. A product outlet 15 and a gas phase outlet 19 are provided between the feed port 12 and the gas-liquid inlet 18, with the gas phase outlet 19 located above the product outlet 15. An annular flow channel 14 is provided at the product outlet 15. The sidewall of the annular flow channel 14 is provided with a channel and communicates with the reactor 1. A filter screen 16 is provided in the channel.

[0035] The product outlet 15 of the reactor 1 is connected to the liquid phase inlet 43 of the Venturi gas-liquid ejector 6 via a heat exchanger 3 and a circulating pump 5 in sequence. The gas phase outlet 19 of the reactor 1 is connected to the gas phase inlet 42 of the Venturi gas-liquid ejector 6. The gas-liquid outlet 41 of the Venturi gas-liquid ejector 6 is connected to the gas-liquid inlet 18 of the reactor 1.

[0036] In this embodiment, the reactor 1 is a cylindrical structure. From the gas-liquid inlet 18 to the feed port 12, there are sequentially a catalyst suspension zone I, a settling zone II, and a gas phase zone IV. The area of ​​the annular flow channel 14 is a solid phase separation zone III. The catalyst suspension zone I, settling zone II, and solid phase separation zone III are the main sites of the gas-liquid-solid three-phase reaction. The diameter of the catalyst suspension zone I is smaller than the diameter of the settling zone II; that is, the catalyst suspension zone I includes a variable diameter zone and a small diameter zone, while the settling zone is a large diameter zone. This not only ensures that the gas-liquid-solid three phases are evenly dispersed in the catalyst suspension zone I, but also facilitates the settling of the solid catalyst in the settling zone II, which helps prevent the solid catalyst from entering the liquid phase outlet 15.

[0037] In this embodiment, the annular flow channel 14 has a fan-shaped pore shape, and the maximum pore size of the filter screen 16 is smaller than the average particle size of the solid catalyst.

[0038] Example 2

[0039] As described in Example 1, the difference is:

[0040] The gas phase outlet 19 of the reactor 1 is also connected to the gas inlet valve 9. The gaseous raw material from the gas inlet valve 9 and the separated gas phase from the gas phase outlet 19 both enter the gas phase inlet 42 of the Venturi gas-liquid injector 6. The gaseous raw material can be continuously replenished into the reaction system.

[0041] Example 3

[0042] As described in Example 1 or 2, except that:

[0043] A product discharge valve 2 is also provided between the product outlet 15 and the heat exchanger 3 for discharging the reaction product.

[0044] Example 4

[0045] As described in Example 1 or 2 or 3, except that:

[0046] A material inlet valve 4 is also provided between the heat exchanger 3 and the circulating pump 5 for adding liquid reaction material into the reaction system. The material inlet valve 4 continuously supplements the liquid raw material into the reaction system, the gas inlet valve 9 continuously supplements the gas raw material into the system, and the product discharge valve 2 continuously discharges a part of the reaction product, so that the gas-liquid-solid three-phase reaction is realized continuously.

[0047] Example 5

[0048] As described in Example 1 or 2 or 3 or 4, except that:

[0049] A porous baffle 13 is also provided between the product outlet 15 and the gas phase outlet 19 in the reaction kettle 1 for separating the gas phase from the liquid phase in the reaction kettle 1.

[0050] Example 6

[0051] As described in Example 1 or 2 or 3 or 4 or 5, except that:

[0052] The reaction kettle 1 is also provided with a scraper system composed of a servo motor 100, a transmission shaft 101 and a scraper 102. The scraper 102 is located at the same position as the filter screen 16 of the annular flow channel 14, and the scraper 102 is connected to the servo motor 100 through the transmission shaft 101. The scraper 102 is mainly used to remove the solid catalyst on the filter screen 16.

[0053] Example 7

[0054] As described in Example 1 or 2 or 3 or 4 or 5 or 6, except that:

[0055] An auxiliary function port 11 is also provided at the upper part of the reaction kettle 1. The auxiliary function port can be used as a temperature measuring port, a pressure measuring port, a safety valve interface, an observation port, a liquid level meter installation port, etc.

[0056] Example 8

[0057] As described in Example 1 or 2 or 3 or 4 or 5 or 6 or 7, except that:

[0058] A check valve 7 is arranged between the gas-liquid inlet 18 of the reactor 1 and the gas-liquid outlet 41 of the venturi gas-liquid ejector 6, and a vent valve 8 is arranged between the check valve 7 and the gas-liquid inlet 18 of the reactor 1.

[0059] Example 9

[0060] As described in Example 1 or 2 or 3 or 4 or 5 or 6 or 7 or 8, except that:

[0061] The bottom of the annular flow channel 14 is provided with a discharge port 17.

[0062] Example 10

[0063] A method for carrying out a gas-liquid-solid three-phase reaction using the continuous loop reactor of any one of Examples 1-9, comprising the following steps:

[0064] The solid catalyst is added into the reactor 1 through the feed port 12, the gaseous raw material is fed into the gas phase inlet 42 of the venturi gas-liquid ejector 6 through the gas inlet valve 9, the liquid raw material is fed into the circulating pump 5 through the material inlet valve 4 for pressurization and then fed into the liquid phase inlet 43 of the venturi gas-liquid ejector 6, the venturi gas-liquid ejector 6 mixes the gas-liquid two phases and then enters the reactor 1 through the gas-liquid inlet 18, and the gas-liquid-solid three-phase reaction is carried out with the solid catalyst in the reactor 1, the liquid phase product is discharged from the product outlet 15 and divided into two parts, one part of the product flows into the next section through the product discharge valve 2, and the other part of the product is heated by the heat exchanger 3 and then mixed with the raw material supplemented through the material inlet valve 4, pressurized by the circulating pump 5, and then fed into the liquid phase inlet 43 of the venturi gas-liquid ejector 6, and then enters the reactor 1 through the gas-liquid inlet 18 for continuous gas-liquid-solid three-phase circulation loop reaction. The flow rate of the raw material supplemented through the material inlet valve 4 is the same as the flow rate of the product discharged through the product discharge valve 2.

[0065] The present application is provided with an annular flow channel 14 at the product outlet 15 of the reactor 1, the side wall of the annular flow channel 14 is provided with a hole and communicates with the reactor 1, a filter screen 16 is arranged in the hole, and a scraper system continuously removes the solid catalyst on the filter screen 16, which can block the solid catalyst from flowing out with the liquid phase, thereby avoiding the solid catalyst entering the circulating pump 5 and ensuring the reaction activity of the solid catalyst. The multi-hole baffle 13 is used for separating the gas phase and the liquid phase to avoid the liquid phase entering the gas phase outlet 19. The reactor 1, the heat exchanger 3, the circulating pump 5, and the venturi gas-liquid ejector 6 are connected to form a circulation loop, which is very conducive to the circulation loop reaction of the gas-liquid-solid three-phase. At the same time, the material inlet valve 4 continuously supplements the liquid raw material into the reaction system, the gas inlet valve 9 continuously supplements the gaseous raw material into the system, and the product discharge valve 2 continuously discharges part of the reaction product, so that the gas-liquid-solid three-phase reaction is realized continuously.

Claims

1. A continuous loop reactor for gas-liquid-solid three-phase reactions, characterized in that, The continuous loop reactor comprises a reaction kettle, a heat exchanger, a circulating pump and a Venturi gas-liquid ejector, the upper and lower portions of the reaction kettle are respectively provided with a feeding opening and a gas-liquid inlet, a product outlet and a gas phase outlet are arranged between the feeding opening and the gas-liquid inlet, the gas phase outlet is located above the product outlet, an annular flow channel is arranged at the product outlet, the side wall of the annular flow channel is provided with a hole communicating with the reaction kettle, and a filter screen is arranged in the hole; the product outlet of the reaction kettle is connected with the liquid phase inlet of the Venturi gas-liquid ejector through the heat exchanger and the circulating pump in sequence, the gas phase outlet of the reaction kettle is connected with the gas phase inlet of the Venturi gas-liquid ejector, and the gas-liquid outlet of the Venturi gas-liquid ejector is connected with the gas-liquid inlet of the reaction kettle; a perforated baffle is further arranged between the product outlet and the gas phase outlet in the reaction kettle, the reaction kettle is further provided with a scraper system composed of a servo motor, a transmission shaft and a scraper, the scraper is located at the same position as the filter screen of the annular flow channel, and the scraper is connected with the servo motor through the transmission shaft; the reaction kettle has a cylindrical structure, and from the gas-liquid inlet to the feeding opening, the reaction kettle sequentially comprises a catalyst suspension zone, a settling zone and a gas phase zone, the region of the annular flow channel is a solid phase separation zone, and the diameter of the catalyst suspension zone is smaller than the diameter of the settling zone.

2. The continuous loop reactor for gas-liquid-solid three-phase reactions according to claim 1, characterized in that, The gas phase outlet of the reaction kettle is further connected with a gas inlet valve.

3. The continuous loop reactor for gas-liquid-solid three-phase reactions according to claim 1, characterized in that, A product discharge valve is further arranged between the product outlet and the heat exchanger.

4. The continuous loop reactor for gas-liquid-solid three-phase reactions according to claim 1, characterized in that, A material inlet valve is further arranged between the heat exchanger and the circulating pump.

5. The continuous loop reactor for gas-liquid-solid three-phase reactions according to claim 1, characterized in that, An auxiliary function opening is further arranged at the upper portion of the reaction kettle.

6. The continuous loop reactor for gas-liquid-solid three-phase reactions according to claim 1, characterized in that, A check valve is further arranged between the gas-liquid inlet of the reaction kettle and the gas-liquid outlet of the Venturi gas-liquid ejector, and an emptying valve is arranged between the check valve and the gas-liquid inlet of the reaction kettle.

7. The continuous loop reactor for gas-liquid-solid three-phase reactions according to claim 1, characterized in that, The hole of the annular flow channel is in the shape of a sector.

8. The continuous loop reactor for gas-liquid-solid three-phase reactions according to claim 1, characterized in that, The maximum pore size of the filter screen is smaller than the average particle size of the solid catalyst, and a discharge opening is arranged at the bottom of the annular flow channel. 9.A method for gas-liquid-solid three-phase continuous loop reaction, comprising using the continuous loop reactor according to any one of claims 1-8, comprising the following steps: the solid catalyst is added into the reaction kettle through the feeding opening, the gas raw material is introduced into the gas phase inlet of the Venturi gas-liquid ejector through the gas inlet valve, the liquid raw material is introduced into the circulating pump through the material inlet valve for pressurization and then introduced into the liquid phase inlet of the Venturi gas-liquid ejector, the gas-liquid two-phase mixture is introduced into the reaction kettle through the gas-liquid inlet after being mixed by the Venturi gas-liquid ejector, the gas-liquid-solid three-phase reaction is carried out with the solid catalyst in the reaction kettle, the liquid phase product is discharged from the product outlet and is divided into two parts, one part of the product flows into the next process through the product discharge valve, and the other part of the product is mixed with the raw material supplemented through the material inlet valve after heat exchange through the heat exchanger, is pressurized by the circulating pump, is introduced into the liquid phase inlet of the Venturi gas-liquid ejector, and then is introduced into the reaction kettle through the gas-liquid inlet to carry out continuous gas-liquid-solid three-phase circulation loop reaction.

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