Fluidized bed reactor and epoxypropane preparation device

Abstract

The invention discloses a fluidized bed reactor and an epoxypropane preparation device. The fluidized bed reactor comprises a shell and a tube pass, the shell is provided with a feeding section, a reaction section and a discharging section which are sequentially arranged, the tube pass is communicated with the feeding section and the discharging section, and the tube pass is of a spiral structure. The fluidized bed reactor can improve the heat dissipation effect of reaction heat of propylene and hydrogen peroxide, so that the effective utilization rate of hydrogen peroxide and the selectivity of epoxypropane are improved.

Description

Technical Field

[0001] This application belongs to the field of fluidized bed technology, specifically relating to a fluidized bed reactor and an apparatus for preparing propylene oxide. Background Technology

[0002] Propylene oxide, a key derivative of propylene, is mainly used in the production of polyether polyols, propylene glycol, propylene carbonate, and other products, and is widely used in the petroleum, chemical, pesticide, textile, and daily chemical industries. Currently, the process of directly oxidizing propylene with hydrogen peroxide to produce propylene oxide is considered one of the fastest-growing and most promising technologies due to its simple process, mild reaction conditions, and environmental friendliness.

[0003] However, in this process, the direct oxidation of propylene by hydrogen peroxide is exothermic. The propylene oxide preparation unit, as the apparatus for implementing this process, needs to effectively and promptly dissipate the heat generated by the direct oxidation of propylene by hydrogen peroxide. If the heat generated within the propylene oxide preparation unit cannot be effectively dissipated, it may lead to a localized temperature increase. This could not only cause the hydrogen peroxide to decompose but also trigger other side reactions, thereby reducing the utilization rate of hydrogen peroxide and the selectivity of propylene oxide. In extreme cases, a rapid temperature rise could lead to runaway reaction, resulting in an overpressure safety accident. Summary of the Invention

[0004] This application aims to at least partially solve the technical problem of poor heat dissipation in current propylene oxide preparation equipment. To this end, this application provides a fluidized bed reactor and a propylene oxide preparation apparatus.

[0005] The technical solution of this application is as follows:

[0006] In a first aspect, this application provides a fluidized bed reactor, comprising:

[0007] The shell has a feeding section, a reaction section and a discharging section arranged sequentially.

[0008] A tube is located in the reaction section, the tube connects the feed section and the discharge section, and the tube has a spiral structure.

[0009] In some embodiments, the tube section includes multiple sets of reaction tubes, each set of reaction tubes being arranged sequentially and extending from the feed section to the discharge section in a spiral configuration.

[0010] In some embodiments, the helical directions of adjacent sets of reaction tubes are opposite.

[0011] In some embodiments, each group of reaction tubes is provided with multiple tubes, all rotating in the same direction.

[0012] In some embodiments, the multiple sets of reaction tubes are arranged in a nested structure.

[0013] In some embodiments, the diameter of the reaction tube is 19 mm to 65 mm.

[0014] In some embodiments, the reaction section is provided in multiple ways, and an oxidant replenishment section is provided between two adjacent reaction sections. The oxidant replenishment section is connected to the tube side of the two adjacent reaction sections and is provided with an oxidant replenishment port.

[0015] In some embodiments, the feeding section has a raw material inlet, a solvent inlet, a catalyst inlet, an oxidant inlet, a raw material chamber and a mixing chamber connected in communication, the mixing chamber connecting the raw material chamber and the reaction section, the raw material inlet and the solvent inlet connecting to the raw material chamber, and the catalyst inlet and the oxidant inlet connecting to the mixing chamber.

[0016] In some embodiments, the raw material chamber is provided with the Venturi tube and the mixer, which are arranged sequentially along the direction from the raw material chamber to the mixing chamber. The inlet section of the Venturi tube is connected to the solvent inlet, and the diffusion section of the Venturi tube is correspondingly arranged with the mixer. The chamber between the outer wall of the Venturi tube and the cavity wall of the raw material chamber is connected to the raw material inlet, and the diffusion section of the Venturi tube is provided with a through hole connecting the raw material inlet and the solvent inlet.

[0017] In some embodiments, an orifice plate and a baffle are provided between the raw material chamber and the mixing chamber, the baffle being spaced apart on the side of the orifice plate near the mixing chamber, and the baffle blocking the raw material orifice of the orifice plate.

[0018] Secondly, this application also proposes an apparatus for preparing propylene oxide, comprising:

[0019] The fluidized bed reactor described above has a feed section with a raw material inlet, a solvent inlet, a catalyst inlet, and an oxidant inlet; a reaction section with a coolant inlet and a coolant outlet; and a discharge section with a mixed material outlet.

[0020] A refrigerant circulation system, wherein the output end of the refrigerant circulation system is connected to the refrigerant inlet, and the input end of the refrigerant circulation system is connected to the refrigerant outlet;

[0021] The separating hopper has a mixture inlet, a first diversion outlet and a second diversion outlet. The first diversion outlet is located at the bottom of the separating hopper. Along the height direction of the separating hopper, the position of the mixture inlet is lower than the first diversion outlet and higher than the second diversion outlet.

[0022] A catalyst circulation system, wherein the input end of the catalyst circulation system is connected to the second diversion outlet, and the output end of the catalyst circulation system is connected to the catalyst inlet.

[0023] In some embodiments, the refrigerant circulation system includes a refrigerant circulation pump and a refrigerant cooler connected sequentially from the input end to the output end;

[0024] The catalyst circulation system includes a buffer hopper, a lock hopper, and an elevator connected sequentially from the input end to the output end.

[0025] The catalyst circulation system also includes a regenerator, which is connected between the buffer hopper and the lock hopper. The regenerator is provided with a high-temperature regenerated liquid inlet, a regenerated liquid outlet and a low-temperature regenerated liquid inlet in sequence from top to bottom along the height direction of the regenerator.

[0026] The embodiments of this application have at least the following beneficial effects:

[0027] This application discloses a fluidized bed reactor and a propylene oxide preparation apparatus. The fluidized bed reactor is the core equipment of the propylene oxide preparation apparatus, mainly used to realize the chemical reaction of reactants to generate products. The feed section of the fluidized bed reactor is the area where reactants enter the reactor. In the feed section, the reactants are mixed and begin to form a fluidized state to ensure uniform distribution and prepare for the chemical reaction. The reaction section is the main area where the reactants undergo chemical reaction. In the reaction section, the reactants are in full contact to carry out the chemical reaction. The reaction section provides sufficient contact time and a suitable environment to promote the reaction. The discharge section is the area used to collect the reactants after the chemical reaction, thus preparing them for further processing.

[0028] The reaction section is equipped with a tube side, connecting the feed and discharge sections. This means the chemical reaction between propylene and hydrogen peroxide occurs within the tube side. The reaction section is equivalent to the shell side. Cooling is achieved by placing a refrigerant within the reaction section, positioned between the inner wall of the reaction section and the outer wall of the tube side, to dissipate heat from the tube side and thus cool it. Furthermore, the tube side of the reaction section has a helical tube structure, resulting in turbulent flow of the reactants. This ensures a more complete reaction and higher heat transfer efficiency, thereby improving the heat exchange effect and ultimately enhancing the effective utilization of hydrogen peroxide and the selectivity of propylene oxide. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 This is a schematic diagram of the propylene oxide preparation apparatus according to an embodiment of this application;

[0031] Figure 2 for Figure 1 A schematic diagram of the feed section of the fluidized bed reactor in the propylene oxide preparation unit.

[0032] Figure label:

[0033] 10. Propylene oxide preparation unit; 100. Fluidized bed reactor; 110. Shell; 111. Feed section; 111a. Raw material inlet; 111b. Solvent inlet; 111c. Catalyst inlet; 111d. Oxidant inlet; 111e. Raw material chamber; 111f. Mixing chamber; 112. Reaction section; 112a. Refrigerant inlet; 112b. Refrigerant outlet; 113. Discharge section; 113a. Mixed material outlet; 114. Oxidant replenishment section; 114a. Oxidant replenishment port; 120. Tube side; 121. Reaction tube; 130. Venturi tube; 131. Through hole; 140. Mixing... Combiner; 150, orifice plate; 151, raw material orifice; 160, baffle; 170, distributor; 200, refrigerant circulation system; 210, refrigerant circulation pump; 220, refrigerant cooler; 300, separating hopper; 310, mixed material inlet; 320, first diversion outlet; 330, second diversion outlet; 400, catalyst circulation system; 410, buffer hopper; 411, unloading port; 420, locking hopper; 421, catalyst addition port; 430, elevator; 440, regenerator; 441, high-temperature regenerated liquid inlet; 442, low-temperature regenerated liquid inlet; 443, regenerated liquid outlet. Detailed Implementation

[0034] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0035] Furthermore, reference numerals and / or reference letters may be repeated in different examples in this application. Such repetition is for simplification and clarity purposes and does not in itself indicate a relationship between the various embodiments and / or settings discussed. In addition, this application provides examples of various specific processes and materials; however, those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0036] Propylene oxide, a key derivative of propylene, is mainly used in the production of polyether polyols, propylene glycol, propylene carbonate, and other products, and is widely used in the petroleum, chemical, pesticide, textile, and daily chemical industries. Currently, the process of directly oxidizing propylene with hydrogen peroxide to produce propylene oxide is considered one of the fastest-growing and most promising technologies due to its simple process, mild reaction conditions, and environmental friendliness.

[0037] However, in this process, the direct oxidation of propylene by hydrogen peroxide is an exothermic reaction. The propylene oxide preparation unit 10, as the apparatus for implementing this process, needs to effectively dissipate the heat generated by the direct oxidation of propylene by hydrogen peroxide. If the heat generated within the propylene oxide preparation unit 10 cannot be effectively dissipated, it may lead to a localized temperature increase within the unit. This could not only cause the hydrogen peroxide to decompose but also trigger other side reactions, thereby reducing the utilization rate of hydrogen peroxide and the selectivity of propylene oxide. In extreme cases, a rapid temperature rise could lead to runaway reaction, resulting in an overpressure safety accident.

[0038] In order to improve the heat dissipation effect when preparing propylene oxide in the propylene oxide preparation apparatus 10, this application proposes a fluidized bed reactor 100 and a propylene oxide preparation apparatus 10.

[0039] This application is described below with reference to the accompanying drawings and specific embodiments:

[0040] Please see Figure 1 as well as Figure 2 The first aspect of this application provides a fluidized bed reactor 100. Combined with... Figure 1 The fluidized bed reactor 100 includes a shell 110 and a tube side 120. The shell 110 has a feed section 111, a reaction section 112 and a discharge section 113 arranged sequentially. The tube side 120 connects the feed section 111 and the discharge section 113 and has a spiral structure.

[0041] Specifically, the fluidized bed reactor 100 is the core equipment of the propylene oxide preparation unit 10, mainly used to realize the chemical reaction of reactants to generate products. The feed section 111 of the fluidized bed reactor 100 is the area where reactants enter the reactor. In the feed section 111, the reactants are mixed and begin to form a fluidized state to ensure uniform distribution and prepare for the chemical reaction. The reaction section 112 is the main area where the reactants undergo the chemical reaction. In the reaction section 112, the reactants are in full contact to carry out the chemical reaction. The reaction section 112 provides sufficient contact time and a suitable environment to promote the reaction. The discharge section 113 is the area used to collect the reactants after the chemical reaction, thus preparing them for further processing.

[0042] The chemical reaction between propylene and hydrogen peroxide generates a large amount of heat, primarily occurring within reaction section 112. To dissipate this heat, a tube side 120 is installed within reaction section 112, connecting the feed section 111 and the discharge section 113. In other words, the chemical reaction between propylene and hydrogen peroxide takes place within tube side 120. Reaction section 112 acts as the shell side. By placing a coolant within reaction section 112—specifically, between the inner wall of reaction section 112 and the outer wall of tube side 120—the coolant dissipates heat from tube side 120, thereby cooling the reaction heat of propylene and hydrogen peroxide.

[0043] However, in fluidized bed reactors of related technologies, the tube side of the reaction section is usually a straight tube structure, and the flow of reactants within the tube side is laminar. This results in low reaction uniformity, poor heat exchange efficiency, and the formation of local hot spots, reducing the effective utilization rate of hydrogen peroxide and the selectivity of propylene oxide. In contrast, in the fluidized bed reactor 100 of this application embodiment, the tube side 120 of the reaction section 112 is a helical tube structure, and the flow of reactants within the tube side 120 is turbulent. This allows for more complete reaction of the reactants, resulting in higher heat transfer efficiency, thereby improving the heat exchange effect and ultimately enhancing the effective utilization rate of hydrogen peroxide and the selectivity of propylene oxide.

[0044] Furthermore, the fluidized bed reactor 100 is typically arranged vertically, with the feed section 111, reaction section 112, and discharge section 113 arranged vertically from bottom to top. With the reaction section 112 of the fluidized bed reactor 100 having the same height, using a helical tube structure increases the length of the tube side 120, thus increasing the reaction time of propylene and hydrogen peroxide within the reaction section 112, resulting in a more complete reaction. In other words, with the same length of the tube side 120 of the reaction section 112, using a helical tube structure reduces the height of the fluidized bed reactor 100, reducing its space requirements and thus lowering the construction cost of the propylene oxide preparation unit 10.

[0045] In some implementations, such as Figure 1 As shown, the tube side 120 includes multiple sets of reaction tubes 121. Each set of reaction tubes 121 is arranged sequentially and extends from the feed section 111 to the discharge section 113 in a spiral configuration. The tube side 120 of the reaction section 112 is composed of spirally structured reaction tubes 121. The number of reaction tubes 121 corresponds to the flow rate of the reactants in the fluidized bed reactor 100. An increase in the number of reaction tubes 121 means an increase in the flow rate of the reactants in the fluidized bed reactor 100, thereby improving the preparation efficiency of the fluidized bed reactor 100.

[0046] In some implementations, such as Figure 1 As shown, the spiral directions of adjacent groups of reaction tubes 121 are opposite. Setting the spiral directions of adjacent groups of reaction tubes 121 to opposite directions avoids overlap of adjacent groups of reaction tubes 121 in the spiral direction, thereby improving the heat exchange effect of the refrigerant on the reaction tubes 121.

[0047] In some implementations, such as Figure 1 As shown, each group has multiple reaction tubes 121 arranged in the same spiral direction. By arranging multiple reaction tubes 121 in each group in the same spiral direction, the heat exchange effect is ensured while the arrangement of the reaction tubes 121 is made more uniform, increasing the number of reaction tubes 121 in the reaction section 112, thereby improving the preparation efficiency of the fluidized bed reactor 100.

[0048] In some implementations, such as Figure 1 As shown, multiple sets of reaction tubes 121 are arranged in a nested structure. That is, each set of reaction tubes 121 is arranged in a circle, and multiple sets of reaction tubes 121 are arranged around the same center, thus forming a nested structure. This increases the number of reaction tubes 121 while ensuring the heat exchange effect of the refrigerant on the reaction tubes 121. Furthermore, when multiple reaction tubes 121 in each set of the tube side 120 are spiraled in the same direction, the spiral directions of adjacent sets of reaction tubes 121 are opposite to improve the heat exchange effect of the refrigerant on the reaction tubes 121.

[0049] In some embodiments, the diameter of the reaction tube 121 is 19mm to 65mm. To ensure the flow rate and heat exchange effect of the reaction tube 121, and to avoid both excessively small diameters that would reduce the flow rate of the reactants and excessively large diameters that would reduce the heat exchange effect, the diameter of the reaction tube 121 is set to 19mm to 65mm. Optional specifications for the reaction tube 121 include 19mm, 25mm, 38mm, 50mm, and 65mm.

[0050] In some implementations, such as Figure 1 As shown, multiple reaction sections 112 are provided, and an oxidant replenishment section 114 is provided between two adjacent reaction sections 112. The oxidant replenishment section 114 is connected to the tube side 120 of the two adjacent reaction sections 112 and is provided with an oxidant replenishment port 114a. In the direction from the feed section 111 to the discharge section 113 of the fluidized bed reactor 100, by setting multiple reaction sections 112 and setting oxidant replenishment sections 114 between two adjacent reaction sections 112, the heat of reaction of the reactants is dispersed in each reaction section 112, rather than concentrated in one reaction section 112, thus improving the heat exchange effect. At the same time, it also promotes a more complete chemical reaction of the reactants, improving the reaction efficiency.

[0051] In some implementations, such as Figure 1 as well as Figure 2As shown, the feed section 111 has a raw material inlet 111a, a solvent inlet 111b, a catalyst inlet 111c, an oxidant inlet 111d, a raw material chamber 111e connected to it, and a mixing chamber 111f. The mixing chamber 111f connects the raw material chamber 111e to the reaction section 112. The raw material inlet 111a and the solvent inlet 111b are connected to the raw material chamber 111e, and the catalyst inlet 111c and the oxidant inlet 111d are connected to the mixing chamber 111f. The raw material inlet 111a of the feed section 111 is used to feed propylene into the feed section 111, the solvent inlet 111b is used to feed solvent into the feed section 111, the catalyst inlet 111c is used to feed catalyst into the feed section 111, and the oxidant inlet 111d is used to feed hydrogen peroxide into the feed section 111. To improve the reaction efficiency, the feed section 111 is configured as a raw material chamber 111e and a mixing chamber 111f. The mixing chamber 111f is located between the raw material chamber 111e and the reaction section 112, with the raw material inlet 111a and solvent inlet 111b connected to the raw material chamber 111e, and the catalyst inlet 111c and oxidant inlet 111d connected to the mixing chamber 111f. This allows propylene and solvent to enter the raw material chamber 111e through the raw material inlet 111a and solvent inlet 111b for initial mixing, and then enter the mixing chamber 111f to mix with the catalyst and hydrogen peroxide that enter the mixing chamber 111f through the catalyst inlet 111c and oxidant inlet 111d.

[0052] In some implementations, such as Figure 1 as well as Figure 2As shown, a Venturi tube 130 and a mixer 140 are provided in the raw material chamber 111e. The Venturi tube 130 and the mixer 140 are arranged sequentially along the direction from the raw material chamber 111e to the mixing chamber 111f. The inlet section of the Venturi tube 130 is connected to the solvent inlet 111b, and the diffusion section of the Venturi tube 130 is correspondingly arranged with the mixer 140. The chamber between the outer wall of the Venturi tube 130 and the cavity wall of the raw material chamber 111e is connected to the raw material inlet 111a. The diffusion section of the Venturi tube 130 is provided with a through hole 131 connecting the raw material inlet 111a and the solvent inlet 111b. Solvent inlet 111b is located at the bottom of feed section 111, raw material inlet 111a is located on the peripheral wall of feed section 111, and venturi tube 130 is vertically arranged in the raw material cavity 111e of feed section 111 so that the inlet section of venturi tube 130 communicates with solvent inlet 111b. Housing 110 is fitted onto venturi tube 130, thereby forming a chamber between the outer wall of venturi tube 130 and the cavity wall of raw material cavity 111e. The through hole 131 on the diffuser section of venturi tube 130 is used to connect the inner cavity of venturi tube 130 and the chamber between the outer wall of venturi tube 130 and the cavity wall of raw material cavity 111e. When propylene and solvent are fed into the raw material chamber 111e through the raw material inlet 111a and solvent inlet 111b, the solvent sequentially passes through the solvent inlet 111b of the feed section 111 and the inlet section, contraction section and throat of the Venturi tube 130 before entering the diffusion section of the Venturi tube 130. This creates a negative pressure in the diffusion section of the Venturi tube 130. Under the action of the negative pressure, the raw material sequentially passes through the raw material inlet 111a of the feed section 111, the chamber between the outer wall of the Venturi tube 130 and the cavity wall of the raw material chamber 111e, and the through hole 131 of the diffusion section of the Venturi tube 130 before entering the diffusion section of the Venturi tube 130, thereby improving the mixing effect of propylene and solvent.

[0053] In some implementations, the mixer 140 is typically a static mixer of the SV type, SK type, or SX type, etc., and this application embodiment does not limit this.

[0054] In some implementations, such as Figure 2 As shown, the diffuser section of the Venturi tube 130 has multiple through holes 131, with a spacing of 3mm to 10mm between adjacent through holes 131, and a hole diameter of 1mm to 3mm. By setting the number of through holes 131 in the diffuser section of the Venturi tube 130 to be multiple and the spacing of adjacent through holes 131 to be 3mm to 10mm, the conveying effect of the feed section 111 on the raw materials is ensured. Furthermore, by setting the hole diameter of the through holes 131 to 1mm to 3mm, the droplet diameter of propylene is reduced, the reaction transfer area of ​​propylene is increased, thereby allowing for better mixing of propylene and solvent, and better reaction of propylene and hydrogen peroxide.

[0055] In some implementations, such as Figure 2 As shown, an orifice plate 150 and a baffle plate 160 are provided between the raw material chamber 111e and the mixing chamber 111f. The baffle plate 160 is spaced apart on the side of the orifice plate 150 near the mixing chamber 111f, and blocks the raw material holes 151 of the orifice plate 150. The orifice plate 150 is located between the raw material chamber 111e and the mixing chamber 111f in the feed section 111. The orifice plate 150 has multiple raw material holes 151 to allow the mixture of raw material and solvent in the raw material chamber 111e to enter the raw material chamber 111e through the raw material holes 151 of the orifice plate 150. Since the catalyst is fed into the mixing chamber 111f through the catalyst inlet 111c, and the catalyst is a solid particle, a baffle plate 160 is provided at the raw material holes 151 of the orifice plate 150 to prevent the catalyst from entering the raw material chamber 111e through the raw material holes 151 of the orifice plate 150, thereby blocking the catalyst from entering the raw material chamber 111e. Meanwhile, the baffle 160 and the orifice plate 150 are spaced apart so that after the mixed solution is discharged from the raw material hole 151 of the orifice plate 150, it enters the mixing chamber 111f from the side of the baffle 160, thereby avoiding obstruction of the mixed solution by the baffle 160. The baffle 160 is usually composed of two plates arranged at an angle. The baffle 160 is placed on the raw material hole 151 of the orifice plate 150, and the mixed solution enters the mixing chamber 111f from both sides of the baffle 160.

[0056] In some implementations, such as Figure 1 As shown, in the direction from feed section 111 to discharge section 113, catalyst inlet 111c and oxidant inlet 111d are sequentially arranged on the peripheral wall of feed section 111. This allows propylene to be mixed with solvent and catalyst before contacting with hydrogen peroxide, thereby improving the reaction efficiency.

[0057] In some implementations, such as Figure 1 As shown, the fluidized bed reactor 100 also includes a distributor 170. The main body of the distributor 170 is located within the mixing chamber 111f of the feed section 111. The main body of the distributor 170 is equipped with multiple nozzles, and the tube of the distributor 170 extends through the oxidant inlet 111d. Hydrogen peroxide enters the main body of the distributor 170 through the tube and is then injected into the mixing chamber 111f of the feed section 111 through the nozzles on the main body of the distributor 170 to improve the mixing effect. Furthermore, the oxidant replenishment section 114 is also equipped with a distributor 170. The main body of the distributor 170 is located within the oxidant replenishment section 114, and the tube of the distributor 170 extends through the oxidant replenishment port 114a to similarly improve the mixing effect.

[0058] Please see Figure 1 In a second aspect of this application, an apparatus 10 for preparing propylene oxide is also provided. (In conjunction with...) Figure 1The propylene oxide preparation apparatus 10 includes a refrigerant circulation system 200, a separation hopper 300, a catalyst circulation system 400, and a fluidized bed reactor 100 according to the first aspect of this application.

[0059] In this embodiment, the feed section 111 of the fluidized bed reactor 100 has a raw material inlet 111a, a solvent inlet 111b, a catalyst inlet 111c, and an oxidant inlet 111d; the reaction section 112 has a refrigerant inlet 112a and a refrigerant outlet 112b; and the discharge section 113 has a mixture outlet 113a. The output end of the refrigerant circulation system 200 is connected to the refrigerant inlet 112a of the fluidized bed reactor 100, and the input end of the refrigerant circulation system 200 is connected to the refrigerant outlet 112b of the fluidized bed reactor 100. The mixture inlet 310 of the separation hopper 300 is connected to the mixture outlet 113a of the fluidized bed reactor 100. The input end of the catalyst circulation system 400 is connected to the second diversion outlet 330 of the separation hopper 300, and the output end of the catalyst circulation system 400 is connected to the catalyst inlet 111c of the fluidized bed reactor 100.

[0060] Specifically, the feed section 111 has a raw material inlet 111a, a solvent inlet 111b, a catalyst inlet 111c, and an oxidant inlet 111d, through which reactants are introduced into the feed section 111. The raw material inlet 111a is used to feed propylene, the solvent inlet 111b is used to feed solvent, the catalyst inlet 111c is used to feed catalyst, and the oxidant inlet 111d is used to feed hydrogen peroxide. After the propylene, solvent, catalyst, and hydrogen peroxide are mixed in the feed section 111, they enter the reaction section 112. The reaction section 112 has a refrigerant inlet 112a and a refrigerant outlet 112b. Refrigerant is introduced into the reaction section 112 through the refrigerant inlet 112a. The refrigerant in the reaction section 112 exchanges heat with the tube side 120 to reduce the temperature of the tube side 120. After the heat exchange is completed, the refrigerant is discharged to the outside of the shell side through the refrigerant outlet 112b, thereby achieving heat dissipation of the reaction heat of propylene and hydrogen peroxide.

[0061] The output end of the refrigerant circulation system 200 is connected to the refrigerant inlet 112a of the fluidized bed reactor 100, and the input end of the refrigerant circulation system 200 is connected to the refrigerant outlet 112b of the fluidized bed reactor 100. This allows refrigerant to be introduced into the reaction section 112 of the fluidized bed reactor 100 through the refrigerant circulation system 200, thereby dissipating the heat of reaction within the reaction section 112. The refrigerant, whose temperature has increased due to heat exchange, exits from the refrigerant outlet 112b of the reaction section 112 and enters the refrigerant circulation system 200. After being cooled by the refrigerant circulation system 200, the cooled refrigerant is then introduced back into the reaction section 112 through the refrigerant inlet 112a to continue heat exchange. This, in turn, achieves continuous heat dissipation of the heat of reaction within the reaction section 112 through the refrigerant circulation system 200.

[0062] The mixing inlet 310 of the separation hopper 300 is connected to the mixing outlet 113a of the fluidized bed reactor 100. The discharge section 113 of the fluidized bed reactor 100 is used to collect substances that have completed the chemical reaction in the reaction section 112. For the propylene oxide preparation apparatus 10, after the propylene, solvent, catalyst, and hydrogen peroxide have completed the chemical reaction, the main substances in the discharge section 113 of the fluidized bed reactor 100 are a mixture of propylene oxide, solvent, and catalyst, wherein propylene oxide and solvent are both liquids, and the catalyst is solid particles. In order to separate the substances that have completed the chemical reaction in the discharge section 113, the separation hopper 300 is connected to the mixing outlet 113a of the discharge section 113. The separation hopper 300 has a first diversion outlet 320 and a second diversion outlet 330. The first diversion outlet 320 is located at the bottom of the separation hopper 300. When the mixture in the reaction section 112 enters the separation hopper 300 through the mixture inlet 310, the mixture will be diverted under the action of gravity. Among them, the catalyst, which is a solid particle, will be discharged from the first diversion outlet 320 of the separation hopper 300, and the propylene oxide and formaldehyde, which are liquids, will be discharged from the second diversion outlet 330 of the separation hopper 300, thereby realizing the diversion of the mixture.

[0063] Furthermore, in the separation hopper 300, to achieve better separation, the bottom of the separation hopper 300 has a conical structure, and the mixture inlet 310 of the separation hopper 300 faces the tangential direction of the separation hopper 300. When the mixture enters the separation hopper 300 through the mixture inlet 310, the mixture will form a swirling flow within the separation hopper 300, and under the action of gravity, due to the uneven pressure distribution of the swirling flow generated by the mixture in the radial direction, the pressure is lower closer to the swirling axis, and the pressure will approach zero at the swirling axis, thus forming a low-pressure zone or even a vacuum zone. In this zone, the less dense substances in the mixture (propylene oxide and solvent) will rotate and concentrate towards the swirling axis, while the more dense substances in the mixture (catalyst) will swirl down along the inner wall of the separation hopper 300. Because the first diversion outlet 320 is located lower than the mixture inlet 310, and the bottom of the separation hopper 300 has a conical structure, the mixture cannot be discharged quickly from the first diversion outlet 320. Also, because the second diversion outlet 330 is located higher than the mixture inlet 310, the lighter substances concentrate in the low-pressure area and move towards the second diversion outlet 330, thus forming an upward rotational motion, and are eventually discharged from the second diversion outlet 330, while the heavier substances are discharged from the first diversion outlet 320.

[0064] The input end of the catalyst circulation system 400 is connected to the second diversion outlet 330 of the separation hopper 300, and the output end of the catalyst circulation system 400 is connected to the catalyst inlet 111c of the fluidized bed reactor 100. In the propylene oxide preparation apparatus 10, the catalyst, as a recyclable reactant, is separated by the separation hopper 300 and then transported to the catalyst inlet 111c of the fluidized bed reactor 100 through the catalyst circulation system 400, thereby realizing the recycling of the catalyst.

[0065] In some implementations, such as Figure 1 As shown, the refrigerant circulation system 200 includes a refrigerant circulation pump 210 and a refrigerant cooler 220 connected sequentially from the input end to the output end. The refrigerant circulation pump 210, the refrigerant cooler 220, and the fluidized bed reactor 100 are all connected by pipelines. The refrigerant circulation pump 210 provides the circulation power for the refrigerant, and the refrigerant cooler 220 cools the refrigerant, thereby achieving the circulation of the refrigerant between the refrigerant circulation pump 210, the refrigerant cooler 220, and the fluidized bed reactor 100. The refrigerant can be chilled water, and the corresponding refrigerant cooler 220 can be a chilled water heat exchanger, a closed-loop cooling tower, etc., which is not limited in this embodiment. The refrigerant outlet 112b is located at the bottom of the peripheral wall of the reaction section 112, and the refrigerant inlet 112a is located at the top of the peripheral wall of the reaction section 112 to ensure the heat exchange effect of the refrigerant on the tube side 120.

[0066] In some implementations, such as Figure 1 As shown, the catalyst circulation system 400 includes a buffer hopper 410, a lock hopper 420, and a booster 430 connected sequentially from the input end to the output end. The catalyst circulation system 400 also includes a regenerator 440, which is connected between the buffer hopper 410 and the lock hopper 420. Along the height direction of the regenerator 440, from top to bottom, there are a high-temperature regenerated liquid inlet 441, a regenerated liquid outlet 443, and a low-temperature regenerated liquid inlet 442. The separation hopper 300, buffer hopper 410, lock hopper 420, booster 430, and fluidized bed reactor 100 are all connected by pipelines, as are the buffer hopper 410, regenerator 440, and lock hopper 420. To control the amount of catalyst entering the regenerator 440, a control valve is typically installed on the pipeline between the buffer hopper 410 and the regenerator 440.

[0067] The buffer hopper 410 is a cylindrical container with an internal annular baffle. The lower part of the buffer hopper 410 is connected to a washing medium pipeline. The washing medium enters from the washing medium pipeline into the annular gap between the annular baffle and the inner wall of the buffer hopper 410, and then flows into the buffer hopper 410 through the annular gap to contact the catalyst and wash away the reaction products carried by the catalyst. The bottom of the buffer hopper 410 has a discharge port 411 equipped with a valve, allowing for online catalyst discharge. The lock hopper 420 is a conical container used to adjust the pressure between the regenerator 440 and the reactor, guiding the catalyst circulation and maintaining the stable operation of the catalyst circulation system 400. The top of the lock hopper 420 has a catalyst addition port 421, allowing for online catalyst addition. The booster 430 feeds the catalyst into the feed section 111 of the fluidized bed reactor 100. The booster 430 is a U-shaped pipe with a boosting medium line. The boosting line is divided into two streams: one is the primary stream, which is used to control the catalyst circulation rate, and the other is the secondary stream, which is used for boosting and circulating the catalyst. The total boosting medium flow rate of the two streams is fixed, and the catalyst circulation is controlled by the change in the boosting medium flow rate of the primary and secondary streams.

[0068] Regenerator 440 is used for catalyst regeneration. To maintain high catalyst activity and selectivity, it is necessary to regenerate some deactivated catalyst to restore its activity. Regenerator 440 adopts a two-stage regeneration process: the upper stage is high-temperature regeneration, with a high-temperature regeneration liquid inlet 441, and the lower stage is low-temperature regeneration, with a low-temperature regeneration liquid inlet 442. A small portion of the catalyst is fed from buffer hopper 410 to regenerator 440 via a control valve. The upper stage of regenerator 440 is connected to the high-temperature regeneration medium, which flows downward and contacts the catalyst flowing downward by gravity in the forward direction, replacing most of the toxic substances in the catalyst. The lower stage of regenerator 440 is connected to the low-temperature regeneration medium, which flows upward and contacts the catalyst flowing downward by gravity in the reverse direction, replacing and washing away the remaining toxic substances, completely restoring catalyst activity, and simultaneously lowering the catalyst temperature. The replaced high-temperature and low-temperature regeneration media merge in the middle of regenerator 440 and are discharged from the regeneration liquid outlet 443 in the middle of regenerator 440, and sent downstream for further processing and recycling.

[0069] In some embodiments, the catalyst is a TS-1 type titanium-silicon molecular sieve HPPO catalyst, which consists of solid particles with a diameter of 0.5 mm to 1 mm. The amount of catalyst regenerated in the regenerator 440 is 10 wt% to 20 wt% of the total catalyst in the propylene oxide preparation unit 10. The hydrogen peroxide concentration is 50% to 60 wt%. The reaction conditions for the direct oxidation of propylene by hydrogen peroxide in the propylene oxide preparation unit 10 are: temperature: 25℃ to 35℃; pressure: 2.4 MPa to 3.0 MPa; molar ratio of propylene to hydrogen peroxide: 1.2 to 1.5:1; molar ratio of methanol to hydrogen peroxide: 3 to 6:1. The flow rate of the reactants in the fluidized bed reactor 100 is 0.1 m / s to 0.4 m / s. When the fluidized bed reactor 100 has two reaction sections 112, the temperature of the coolant in the first and second sections is 5℃ to 15℃. In a fluidized bed reactor 100 with four reaction sections 112, the temperature of the coolant in the third and fourth sections is 30℃~40℃. The pressure of the coolant in reaction section 112 is 0.5MPa~0.7MPa. The washing medium is methanol, and the washing temperature is 25℃~35℃. The regeneration medium is methanol, with a high-temperature regeneration temperature of 100℃~150℃ and a low-temperature regeneration temperature of 25℃~35℃. The pressure in the regenerator 440 is 2.5MPa~3.0MPa.

[0070] Example 1:

[0071] With two reaction sections 112 within the fluidized bed reactor 100, the diameter of the reaction pipe 121 is 25 mm, and the coolant is circulating water. The reactants contain 99.6% propylene by volume, have a hydrogen peroxide concentration of 50%, and use methanol as the solvent. The molar ratio of hydrogen peroxide to propylene to methanol is 1:2.5:5. The reaction temperature of the fluidized bed reactor 100 is 35℃, the reaction pressure is 2.5 MPa, and the flow velocity of the liquid phase material in the fluidized bed reactor 100 is 0.2 m / s. Therefore, the propylene oxide production capacity is 200,000 tons / year.

[0072] Example 2:

[0073] With four reaction sections 112 within the fluidized bed reactor 100, the diameter of the reaction pipe 121 is 25 mm, and the coolant is circulating water. The reactants contain 99.6% propylene by volume, have a hydrogen peroxide concentration of 50%, and use methanol as the solvent. The molar ratio of hydrogen peroxide to propylene to methanol is 1:2.5:5. The reactor temperature is 35℃, the reaction pressure is 2.5 MPa, the flow velocity of the liquid phase in the fluidized bed reactor 100 is 0.2 m / s, and the propylene oxide production capacity is 200,000 tons / year.

[0074] Compared with existing fixed-bed tubular reactor processes used in industrial applications, the reaction efficiency is significantly improved, and the height of the fluidized bed reactor is significantly reduced. The specific results are shown in the table below:

[0075] project Example 1 Example 2 Fixed bed tube process Reaction pressure (MPa) 2.5 2.5 2.7～3.3 Reaction temperature (°C) 35 35 40～44 Hydrogen peroxide conversion rate (%) 99.96 99.92 96.5 Hydrogen peroxide utilization rate (%) 99.99 99.99 86.1 propylene oxide selectivity (%) 99.75 99.55 97.8 Reaction temperature rise (°C) 0.4 0.8 4 Reactor height (m) 12 22 20 (5 units in series) Equipment investment 0.5 0.78 1 (Benchmark)

[0076] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0077] In the description of this application, 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", and "counterclockwise" 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 application 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 application.

[0078] It should be noted that all directional indications in the embodiments of this application are only used to explain the relative positional relationship and movement of each component in a specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0079] In this application, unless otherwise expressly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0080] Furthermore, the use of terms such as "first" and "second" in this application is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, features defined with "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0081] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. In addition, those skilled in the art can combine and integrate the different embodiments or examples described in this specification.

[0082] Furthermore, the technical solutions of the various embodiments can be combined with each other, but only if they are based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed in this application.

[0083] Although embodiments of this application have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the claims and their equivalents.

Claims

1. A fluidized bed reactor, characterized by, The fluidized bed reactor comprises: a housing having a feeding section, a reaction section and a discharging section arranged in sequence; a tube passage arranged in the reaction section, the tube passage being communicated with the feeding section and the discharging section, and the tube passage being in a spiral structure.

2. The fluidized bed reactor of claim 1, wherein, The tube passage comprises a plurality of groups of reaction tubes, each group of the reaction tubes being arranged in sequence and extending from the feeding section to the discharging section, and the reaction tubes being arranged in a spiral structure.

3. The fluidized bed reactor of claim 2, wherein, The spiral directions of the reaction tubes of two adjacent groups are opposite.

4. The fluidized bed reactor of claim 2, wherein, The reaction tubes of each group are arranged in a plurality and have the same rotation direction.

5. The fluidized bed reactor of claim 2, wherein, The reaction tubes of the plurality of groups are arranged in a sleeved structure.

6. The fluidized bed reactor of claim 2, wherein, The tube diameter of the reaction tube is 19mm-65mm.

7. Fluidized bed reactor according to any one of claims 1 to 6, characterized in that The reaction section is arranged in a plurality, and an oxidant supplement section is arranged between two adjacent reaction sections, the oxidant supplement section being communicated with the tube passages of the two adjacent reaction sections, and the oxidant supplement section being provided with an oxidant supplement port.

8. Fluidized bed reactor according to any one of claims 1 to 6, characterized in that The feeding section is provided with a raw material inlet, a solvent inlet, a catalyst inlet, an oxidant inlet, a raw material cavity and a mixing cavity arranged in communication, the mixing cavity being communicated with the raw material cavity and the reaction section, the raw material inlet and the solvent inlet being communicated with the raw material cavity, and the catalyst inlet and the oxidant inlet being communicated with the mixing cavity.

9. The fluidized bed reactor of claim 8, wherein, The raw material cavity is provided with the Venturi tube and the mixer, the Venturi tube and the mixer being arranged in sequence along the direction from the raw material cavity to the mixing cavity, the inlet section of the Venturi tube being communicated with the solvent inlet, the diffusion section of the Venturi tube being correspondingly arranged with the mixer, the chamber between the outer wall of the Venturi tube and the cavity wall of the raw material cavity being communicated with the raw material inlet, and the diffusion section of the Venturi tube being provided with a through hole communicated with the raw material inlet and the solvent inlet.

10. The fluidized bed reactor of claim 8, wherein, A hole plate and a baffle are arranged between the raw material cavity and the mixing cavity, the baffle being arranged at the side of the hole plate close to the mixing cavity, and the baffle being arranged at the raw material hole of the hole plate.

11. An isopropyl oxide production apparatus characterized by comprising: It comprises: The fluidized bed reactor of any one of claims 1-10, the feeding section being provided with a raw material inlet, a solvent inlet, a catalyst inlet and an oxidant inlet, the reaction section being provided with a coolant inlet and a coolant outlet, and the discharging section being provided with a mixed material outlet; a coolant circulation system, an output end of the coolant circulation system being connected with the coolant inlet, and an input end of the coolant circulation system being connected with the coolant outlet; a separation hopper, the separation hopper being provided with a mixed material inlet, a first shunt outlet and a second shunt outlet, the first shunt outlet being arranged at the bottom of the separation hopper, the position of the mixed material inlet being lower than the first shunt outlet and higher than the second shunt outlet along the height direction of the separation hopper; a catalyst circulation system, an input end of the catalyst circulation system being connected with the second shunt outlet, and an output end of the catalyst circulation system being connected with the catalyst inlet.

12. The propylene oxide production apparatus according to claim 11, characterized by The coolant circulation system comprises a coolant circulation pump and a coolant cooler arranged in sequence along the direction from the input end to the output end; The catalyst circulation system comprises a buffer hopper, a lock hopper and an elevator arranged in sequence along the direction from the input end to the output end. The catalyst circulation system further comprises a regenerator connected between the buffer hopper and the lock hopper, which is provided with a high-temperature regenerator liquid inlet, a regenerator liquid outlet and a low-temperature regenerator liquid inlet from top to bottom along the height direction of the regenerator.

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