Rotary microreactor and liquid-liquid extraction method

Abstract

The application belongs to the field of chemical separation method and equipment, and provides a rotating micro-reactor and a liquid-liquid extraction method.The rotating micro-reactor comprises a driving device, a rotating shaft, a centrifugal phase separation structure, a plurality of rotating discs arranged alternately and a fixed ring.The rotating shaft is composed of a rotating disc mounting section and a material conveying section.The rotating disc is horizontally arranged on the rotating disc mounting section, and the fixed ring is horizontally arranged on the inner side wall of the lower shell.The centrifugal phase separation structure is located above the lower shell and comprises a separation cylinder and an upper shell.The bottom of the separation cylinder is provided with a separation cylinder feed inlet.The lower end of the rotating shaft is connected with the driving device, and the upper end is communicated with the separation cylinder feed inlet.The rotating disc mounting section and the liquid inlet are located in the lower shell.The axis of the lower shell is perpendicular to the horizontal plane.The rotating disc, the fixed ring, the rotating shaft and the separation cylinder are coaxially arranged with the lower shell.The application can realize continuous high-efficiency mass transfer and phase separation, and reduce the industrial amplification difficulty of the micro-reactor.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of chemical separation methods and equipment, and relates to a rotating microreactor and a liquid-liquid extraction method. BACKGROUND

[0002] Liquid-liquid extraction is a key separation technology in the field of chemical engineering, and high-efficiency separation of target components is achieved through selective mass transfer between two liquid phases. As a kind of high-efficiency liquid-liquid extraction and chemical reaction process intensification equipment, the microreactor can significantly improve the contact area and mass transfer efficiency of two phases due to its microchannel structure. However, the conventional microreactor is limited by the single-channel volume flux, and its volume is usually less than the order of mL / min, so the actual processing capacity is difficult to meet the application requirements of industrial-scale. At the same time, the two-phase flow in the microchannel of the conventional microreactor is dominated by laminar flow, and the mass transfer process mainly depends on the slow molecular diffusion mechanism, and the interface update rate between the two phases is insufficient, resulting in a significant gap between the actual mass transfer coefficient and the theoretical limit. More prominent problem is that the conventional microreactor generally lacks built-in phase separation function, and needs to rely on external phase separation equipment to realize two-phase separation after extraction, which not only increases the complexity of the extraction system, but also seriously restricts the continuous production process. The above bottleneck problems seriously limit the popularization and application of conventional microreactors in industrial extraction scenarios.

[0003] In recent years, in order to intensify the mass transfer between two phases, there have been reports of microreactors that introduce ultrasonic vibration, electric field regulation, magnetic field induction and other external field energy. By inputting external field energy to disturb the phase interface or regulate the fluid behavior, the mass transfer kinetics can be intensified, and the mass transfer coefficient can be improved by 1-2 orders of magnitude compared to the case without external field. However, the existing microreactors that introduce external field energy to intensify mass transfer still have the following deficiencies to be improved: (1) The input of external field energy can promote the breakup and mixing of dispersed phase, but it cannot simultaneously realize high-efficiency separation of two phases, and the phase separation process still needs to rely on traditional means, such as external phase separation equipment to realize two-phase separation, resulting in low energy utilization efficiency; (2) When the microreactor is scaled up in parallel, the problem of difficult energy field synergistic regulation is faced, and the energy attenuation and interference effect among multiple channels will exacerbate the problem of uneven fluid distribution, further weakening the feasibility of its scaled application. Therefore, it is urgent to develop a microreactor that has both mass transfer intensification and high-efficiency phase separation functions, in order to break through the technical barriers faced by the current conventional microreactor in industrial scaling, and promote the application of microreactors in industrial extraction scenarios. SUMMARY

[0004] In view of the problem that the existing micro-reactor based on external field energy input cannot realize efficient separation of two phases in liquid-liquid extraction, needs to be additionally configured with a phase separation device for phase separation, and has low processing capacity and difficulty in industrial scaling, the application provides a rotating micro-reactor and a liquid-liquid extraction method to realize continuous efficient mass transfer and phase separation and reduce the difficulty in industrial scaling of the micro-reactor.

[0005] To achieve the above-mentioned application purposes, the application adopts the technical solutions as follows:

[0006] A rotating micro-reactor comprises a driving device, a rotating shaft, a shell, rotating discs, fixed rings and a centrifugal phase separation structure.

[0007] The rotating shaft is composed of rotating disc mounting sections and material conveying sections which are connected to each other, and the material conveying sections are provided with liquid inlets and open at the ends. The lower shell is a cylindrical body with closed ends, and the lower shell is provided with a mixing feed inlet, a rotating shaft inlet and a rotating shaft outlet.

[0008] The centrifugal phase separation structure is located above the lower shell, and comprises a separation cylinder and an upper shell which is arranged on the outside of the separation cylinder. The lower end of the rotating shaft is connected to the driving device below the lower shell, the upper end of the rotating shaft is communicated with the separation cylinder inlet, and the rotating disc mounting sections and the liquid inlets are located in the lower shell. The rotating discs and the fixed rings are alternately arranged. The axis of the lower shell is perpendicular to the horizontal plane, and the axes of the rotating discs, the fixed rings, the rotating shaft and the separation cylinder are coincident with the axis of the lower shell. Gaps are formed between the fixed rings and the rotating shaft, between the rotating discs and the inner side wall of the lower shell, and between adjacent rotating discs and fixed rings.

[0009] In the above-mentioned technical solution of the rotating micro-reactor, the separation cylinder is a cylindrical body with closed ends, the upper end surface of the separation cylinder is provided with a light phase outlet, and the upper part of the side wall of the separation cylinder is provided with a heavy phase outlet. The lower end of the upper shell is fixed to the top of the lower shell, and a gap is formed between the inner wall of the upper shell and the separation cylinder. The upper part of the heavy phase outlet and the inner side wall of the upper shell are provided with a first rotary sealing element, and the lower part of the heavy phase outlet and the heavy phase collection weir are provided with a second rotary sealing element. The gaps between the rotating shaft and the rotating shaft inlet and the rotating shaft outlet of the lower shell are provided with third rotary sealing elements.

[0010] The technical scheme of the rotating micro-reactor comprises the following steps: the rotating micro-reactor is provided with a plurality of heavy phase outlets, the heavy phase outlets are arranged around the same height position of the separation cylinder, the distance between each heavy phase outlet and the upper end surface of the separation cylinder is 0.5-10 cm, the aperture of each heavy phase outlet is 1-20 mm, and the aperture and the number of the heavy phase outlets increase with the increase of the processing capacity of the rotating micro-reactor.

[0011] The technical scheme of the rotating micro-reactor comprises the following steps: the rotating micro-reactor comprises a plurality of light phase outlets, each light phase outlet is located in the region close to the axis of the separation cylinder on the upper end surface of the separation cylinder, further, the distance between each light phase outlet and the axis of the separation cylinder is not more than 0.5 times the diameter of the separation cylinder; the aperture of each light phase outlet is 1-20 mm, and the aperture and the number of the light phase outlets increase with the increase of the processing capacity of the rotating micro-reactor. The region between the upper end surface of the separation cylinder and the top of the upper shell is a light phase chamber, and the distance between the upper end surface of the separation cylinder and the top of the upper shell is usually 3-30 cm.

[0012] The technical scheme of the rotating micro-reactor comprises the following steps: the annular gap formed between the inner side wall of the upper shell and the outer side wall of the separation cylinder has a width of 1-10 cm.

[0013] The technical scheme of the rotating micro-reactor comprises the following steps: the heavy phase collection weir is arranged on the inner side wall of the upper shell, and the heavy phase collection weir is arranged around the separation cylinder below the heavy phase outlet.

[0014] The technical scheme of the rotating micro-reactor comprises the following steps: the light phase weir is located above the first rotary seal; the heavy phase collection port is arranged on the upper shell between the first rotary seal and the second rotary seal, and the heavy phase collection port is communicated with the heavy phase collection weir.

[0015] The technical scheme of the rotating micro-reactor comprises the following steps: the separation cylinder is provided with a flow baffle, and the flow baffle is located near the feed inlet of the separation cylinder. Further, the flow baffle is located at the middle position of the lower part of the separation cylinder. Usually, the vertical distance between the flow baffle and the feed inlet of the separation cylinder is 0.5-10 cm.

[0016] Further, the structure of the baffle plate in the above-mentioned rotating micro-reactor is designed with reference to the structure of the baffle plate in the existing centrifugal phase separation device. For example, a feasible structure of the baffle plate is a radial baffle plate, which includes a plurality of blades with the same structure, each blade is uniformly distributed on the central shaft, each blade extends outward along the radial direction of the central shaft, the number of blades is 4-8, and the included angle between adjacent blades is 45-90°. When the structure of the baffle plate is a radial baffle plate, the central shaft of the baffle plate is fixed to the inner wall of the separation cylinder through a fixed rod, so that the central shaft of the baffle plate is parallel to the horizontal plane, and the center of the central shaft of the baffle plate passes through the axis of the separation cylinder. Further, the vertical distance between the end of the blade closest to the feed inlet of the separation cylinder in the baffle plate and the feed inlet of the separation cylinder is 0.5-10 cm, and the distance between the end of the blade closest to the side wall of the separation cylinder in the baffle plate and the side wall of the separation cylinder is 0.4-0.6 times the radius of the separation cylinder.

[0017] In the above-mentioned rotating micro-reactor, the distance between the inner wall of the fixed ring and the outer wall of the rotating shaft is preferably 5-100 mm, the distance between the side wall of the rotating disc and the inner wall of the lower shell is preferably 5-100 mm, and the distance between adjacent rotating discs and the fixed ring in the direction of the rotating shaft axis is preferably 0.5-100 mm.

[0018] In the above-mentioned rotating micro-reactor, the distance between the fixed ring and the adjacent rotating disc above it in the direction of the rotating shaft axis is 0.5-2 times the distance between the fixed ring and the adjacent rotating disc below it in the direction of the rotating shaft axis.

[0019] In the above-mentioned rotating micro-reactor, the center of the rotating disc is provided with a mounting hole with a diameter matching the diameter of the rotating disc mounting section of the rotating shaft, and the rotating disc is fixedly mounted on the rotating disc mounting section through the mounting hole. That is, the cross section of the rotating disc is a ring, and the diameter of the rotating disc refers to the outer diameter of the circular cross section.

[0020] In the above-mentioned rotating micro-reactor, the thickness of the rotating disc is preferably 5-50 mm, the thickness of the fixed ring is preferably 5-50 mm, and the diameter of the rotating disc is preferably 4-150 cm.

[0021] In the above-mentioned rotating micro-reactor, the diameter and material of the rotating shaft are determined according to the mechanical strength of the rotating shaft to meet the actual application requirements, that is, the diameter and material of the rotating shaft should ensure that the rotating shaft is not easily deformed or damaged during use. The diameter of the rotating shaft is positively correlated with the number of rotating discs and the size of the rotating discs, and preferably, the diameter of the rotating shaft is 0.08-0.2 times the diameter of the rotating disc.

[0022] In the technical scheme of the rotating micro-reactor, the fixed annular rings are arranged between adjacent rotating discs, that is, one fixed annular ring is arranged between every two adjacent rotating discs, and thus the number of the fixed annular rings is one less than the number of the rotating discs. The number of the rotating discs is preferably 2-25, that is, N is an integer between 2 and 25.

[0023] In the technical scheme of the rotating micro-reactor, the structures of the rotating discs are the same, and when the number of the fixed annular rings is greater than or equal to 2, the structures of the fixed annular rings are the same.

[0024] In the technical scheme of the rotating micro-reactor, the ratio of the inner diameter of the separation cylinder to the diameter of the rotating disc is preferably (0.6-0.9):1, and the ratio of the height of the separation cylinder to the diameter of the rotating disc is preferably (1-8):1. Generally, the height of the separation cylinder is 6-300 cm.

[0025] In the technical scheme of the rotating micro-reactor, in order to strengthen the turbulence of the liquid-liquid two-phase mixing process in a high-speed shearing field, the upper surface or / and the lower surface of the rotating disc is provided with a plurality of annular or spiral grooves; when the grooves are annular, the axes of all the grooves coincide with the axis of the rotating disc; when the grooves are spiral, the center points (starting points) of the grooves on the upper surface of the rotating disc are located at the center of the upper surface of the rotating disc, and the center points (starting points) of the grooves on the lower surface of the rotating disc are located at the center of the lower surface of the rotating disc. Further, the width and the depth of the grooves are both in the millimeter scale, for example, in the range of 0.2-10 mm. Still further, the width of the groove and the depth of the groove can generally be 0.001-0.01 times the diameter of the rotating disc. Generally, the distance between adjacent grooves is 0.2-2 times the width of the groove.

[0026] In the technical scheme of the rotating micro-reactor, the surface of the fixed annular ring is smooth.

[0027] In the technical scheme of the rotating micro-reactor, the mixing feed inlet is preferably a T-shaped mixing feed inlet or a Y-shaped mixing feed inlet. Further, the channel inner diameter of the mixing feed inlet can be 0.02-0.2 times the diameter of the rotating disc, and the channel inner diameter of the mixing feed inlet is generally 5-40 mm.

[0028] In the technical scheme of the rotating micro-reactor, the rotating disc mounting section and the material conveying section of the rotating shaft are not mutually penetrative, for example, the rotating disc mounting section is in a solid structure, or the two ends of the rotating disc mounting section are closed, and the material conveying section is in a hollow structure with open ends.

[0029] The liquid inlet is arranged on the side wall of the lower part of the material conveying section, and the liquid inlet is arranged in multiple, each liquid inlet is arranged around the side wall of the material conveying section, and the aperture of the liquid inlet is 0.5-20 mm.

[0030] In the technical scheme of the rotating micro-reactor, the materials of the rotating shaft, the upper shell, the lower shell, the rotating disc, the fixed ring, the separation cylinder and the upper shell are preferably duplex stainless steel.

[0031] In the technical scheme of the rotating micro-reactor, the driving device can be a driving motor.

[0032] In the operation process of the rotating micro-reactor, the rotating micro-reactor is supported and fixed by the support frame, and the driving device is also supported and fixed by the support frame, so as to ensure that the position of the rotating shaft remains stable during the operation of the rotating micro-reactor.

[0033] The application also provides a liquid-liquid extraction method, which uses the rotating micro-reactor and comprises the following steps:

[0034] ①Start the driving device to drive the rotating shaft to rotate the rotating disc and the separation cylinder;

[0035] ②The extractant and the liquid to be extracted are continuously introduced into the lower shell through the mixed feed inlet, the liquid-liquid extraction reaction is carried out in the lower shell, and then the material conveying section of the rotating shaft is continuously introduced into the separation cylinder for centrifugal phase separation, and the light phase and the heavy phase after phase separation are continuously discharged from the light phase weir and the heavy phase collection port.

[0036] In the technical scheme of the liquid-liquid extraction method, the rotating speed of the rotating shaft can be determined according to the material characteristics and phase ratio of the two phases required for liquid-liquid extraction, the size of the rotating micro-reactor and other factors, and generally, the rotating speed of the rotating shaft can be controlled to be 500-3000 rpm.

[0037] The principle of the technical scheme of the application is mainly as follows:

[0038] The rotating micro-reactor of the application is coupled by the rotating shaft, the rotating disc in the lower shell and the separation cylinder in the upper shell, and the rotating disc and the separation cylinder are rotated by the driving device to generate a rotational flow field, the shear force provided by the rotational flow field is used to realize high-efficiency mixing of liquid-liquid two phases in the lower shell to promote the mass transfer process of extraction, and the centrifugal force provided by the rotational flow field can realize high-efficiency separation of the mixed phase after mass transfer.

[0039] On one hand, the shear force provided by the rotational flow field in the small scale channel in the lower shell fully disperses one phase into another phase, reduces the droplet size of the dispersed phase, and increases the specific surface area of the dispersed phase in contact with the continuous phase; at the same time, the introduced rotational flow field can change the laminar flow state of the liquid in the conventional microreactor into a turbulent flow state, strengthen the renewal and turbulent motion of the liquid-liquid interface, cause the concentration gradient in the two phases to be renewed and redistributed, strengthen the mass transfer efficiency, and macroscopically shorten the liquid-liquid mass transfer time and improve the processing capacity of the microreactor. On the other hand, the mixed phase after completing the mass transfer is introduced into the separation cylinder, and under the action of the centrifugal force provided by the rotational flow field for the separation cylinder, the two phases in the mixed phase are subjected to different centrifugal accelerations in the separation cylinder due to the different densities, so that the heavy phase with large density is enriched in the area close to the side wall of the separation cylinder in the separation cylinder, and the light phase with small density is enriched in the area close to the axis of the separation cylinder in the separation cylinder, thereby realizing the rapid separation of the liquid-liquid two phases. Under the action of the above two factors, the application effectively couples the mixing and phase separation operations in the microreactor, realizes the continuous mass transfer and phase separation, compared with the operation mode of separate mixing + separate separation adopted in the prior art, the application can reduce the number of equipment and the floor area, and can save the energy consumption and cost of operation and running.

[0040] At the same time, by increasing the number of rotating discs and fixed rings, the processing capacity of the microreactor can be increased by several times, and by increasing the size of the rotating disc, the processing capacity of the microreactor can be increased by square times. The combination of the two aspects significantly improves the processing capacity of the microreactor, and further realizes the industrial amplification of the microreactor, which can effectively solve the problems faced by the conventional microreactor in industrial amplification and parallel amplification.

[0041] Compared with the prior art, the technical scheme provided by the application has the following beneficial technical effects:

[0042] The application provides a rotating micro-reactor and a liquid-liquid extraction method, by setting a plurality of rotating discs and fixed rings alternately distributed in a lower shell, setting a separation cylinder in an upper shell, and coupling the rotating discs in the lower shell and the separation cylinder in the upper shell by a rotating shaft, under the driving of a driving device, the rotating shaft drives the rotating discs and the separation cylinder to rotate to generate a rotational flow field, and the shear force and centrifugal force provided by the rotational flow field are used to realize efficient mixing and separation of liquid-liquid two phases in the lower shell and the upper shell. On the one hand, the shear force provided by the rotational flow field in the micro-scale channel in the lower shell can promote the dispersion of one phase in another phase, reduce the size of the dispersed phase droplets, and increase the specific surface area of the two-phase contact; at the same time, the introduction of the rotational flow field can strengthen the renewal and turbulence of the liquid-liquid interface, promote the renewal and redistribution of the concentration gradient in the two phases, and further strengthen the mass transfer efficiency and shorten the mass transfer time. On the other hand, the centrifugal force provided by the rotational flow field in the separation cylinder can make the two phases in the mixed phase after mass transfer realize rapid phase separation due to different centrifugal accelerations. The above factors make the micro-reactor of the application realize continuous and efficient mass transfer and phase separation. Compared with the existing technology which separately operates the mixing and phase separation processes, the application can reduce the number of equipment and the floor area, and save the energy consumption and cost of operation and running.

[0043] 2. The rotating micro-reactor of the application can double the processing capacity of the micro-reactor by increasing the number of rotating discs and fixed rings, and can enlarge the processing capacity of the micro-reactor in square times by increasing the size of the rotating discs. The double mode of "number enlargement" + "size enlargement" can significantly improve the processing capacity of the micro-reactor and realize the industrial enlargement of the micro-reactor. Taking phosphoric acid extraction as an example, experiments prove that the rotating micro-reactor of the application basically has no adverse effect on the phosphoric acid extraction effect after industrial enlargement. The application can break through the technical bottleneck of the conventional micro-reactor, such as small single-channel processing capacity and uneven fluid distribution caused by parallel multiple micro-channels, which is difficult to realize industrial enlargement. BRIEF DESCRIPTION OF DRAWINGS

[0044] Figure 1 is a structural schematic view of the rotating micro-reactor of the application.

[0045] Figure 2 is a structural schematic view of the rotating shaft of the rotating micro-reactor of the application.

[0046] Figure 3 is a structural schematic view of the upper surface and the lower surface of the rotating disc of the rotating micro-reactor of the application.

[0047] Figure 4 is a structural schematic view of the upper end surface of the separation cylinder of the rotating micro-reactor of the application.

[0048] Figure 5 is a schematic diagram of using the rotating micro-reactor of the present application for phosphoric acid extraction.

[0049] In the figure, 1 is a driving device, 2 is a rotating shaft, 201 is a rotating disc mounting section, 202 is a material conveying section, 203 is a liquid inlet, 3 is a lower shell, 4 is a rotating disc, 5 is a fixed ring, 6 is a mixing feed inlet, 7 is a separation cylinder, 8 is an upper shell, 9 is a light phase outlet, 10 is a heavy phase outlet, 11 is a light phase weir, 12 is a heavy phase collection weir, 13 is a heavy phase collection port, 14 is a first rotating seal, 15 is a second rotating seal, 16 is a third rotating seal, 17 is a flow baffle, 18 is a groove, 19 is an extractant storage tank, 20 is a first conveying pump, 21 is a feed liquid storage tank, and 22 is a second conveying pump. DETAILED DESCRIPTION

[0050] The rotating micro-reactor and liquid-liquid extraction method provided by the present application are further described below through examples. It is necessary to point out that the following examples are only used to further describe the present application and cannot be understood as limiting the protection scope of the present application. Those skilled in the art can make some non-essential improvements and adjustments to the specific implementation of the present application according to the above description, which still belongs to the protection scope of the present application.

[0051] Example 1

[0052] In this embodiment, a rotating micro-reactor is provided, and a structure diagram of the rotating micro-reactor is as shown in Figure 1 which includes a driving device 1, a rotating shaft 2, a shell, a rotating disc 4, a fixed ring 5, and a centrifugal phase separation structure. The shell includes a lower shell 3 and an upper shell 8.

[0053] The rotating shaft 2 is composed of a rotating disc mounting section 201 and a material conveying section 202 which are connected to each other. The material conveying section 202 has a hollow structure and is open at the end. The material conveying section 202 is provided with a liquid inlet 203, and the liquid inlet 203 is located at the lower part of the side wall of the material conveying section 202. Multiple liquid inlets 203 are provided, and each liquid inlet 203 is arranged around the side wall of the material conveying section 202, as shown in Figure 2 The rotating disc mounting section 201 has a solid structure, and the material conveying section 202 has a hollow structure which is open at both ends, i.e., the rotating disc mounting section 201 and the material conveying section 202 are not connected to each other.

[0054] The lower shell 3 is a cylinder with both ends closed, which is specifically composed of a cylinder with the upper end closed and the lower end open, and a lower cover detachably mounted at the lower end of the cylinder, so as to facilitate the maintenance, repair and replacement of the internal components of the lower shell. The bottom of the lower shell 3 is provided with a mixing feed inlet 6 and a rotating shaft inlet, and the top of the lower shell is provided with a rotating shaft outlet; the mixing feed inlet 6 is located near the center of the bottom of the lower shell, and the mixing feed inlet 6 is a T-shaped mixing feed inlet, which is equipped with a control valve.

[0055] The number of rotating discs 4 is 3, each rotating disc 4 has the same structure, the number of fixed rings 5 is 2, each fixed ring 5 has the same structure, and the surfaces of the rotating discs 4 and the fixed rings 5 are smooth; the center of each rotating disc 4 is provided with an installation hole with a size matching the diameter of the rotating disc installation section 201 of the rotating shaft 2, each rotating disc 4 is fixedly installed on the rotating disc installation section 201 of the rotating shaft 2 through the installation hole, and each rotating disc 4 is horizontally installed on the rotating disc installation section 201; the major radius of each fixed ring 5 matches the inner diameter of the lower shell 3, the outer side wall of each fixed ring 5 is fixed to the inner side wall of the lower shell 3, and each fixed ring 5 is horizontally installed on the inner side wall of the lower shell 3.

[0056] The centrifugal phase separation structure is composed of an upper shell 8 and a separation cylinder 7. The separation cylinder 7 is a cylinder with both ends closed, the center of the bottom of the separation cylinder 7 is provided with a separation cylinder feed inlet, and the upper end of the separation cylinder 7 is also provided with a light phase outlet 9 and a heavy phase outlet 10. The light phase outlet 9 is provided with a plurality of light phase outlets 9, each light phase outlet 9 is located in the area near the axis of the separation cylinder 7 on the upper end face of the separation cylinder 7, such as Figure 4The heavy phase outlet 10 is provided with a plurality of heavy phase outlets 10, each of which is located on the upper portion of the side wall of the separation cylinder 7, and each of which is arranged around the same height position of the side wall of the separation cylinder 7. The upper shell 8 is arranged outside the separation cylinder 7, and the lower end of the upper shell 8 is fixed to the top of the lower shell 3. There is a gap between the inner wall of the upper shell 8 and the separation cylinder 7. The upper shell 8 is provided with a light phase weir 11, a heavy phase collection weir 12 and a heavy phase collection port 13. The heavy phase collection weir 12 is arranged on the inner side wall of the upper shell 8, and is arranged around the separation cylinder 7 below the heavy phase outlet 10. More specifically, a circular ring is fixedly arranged on the inner side wall of the upper shell 8, which is located below the heavy phase outlet 10. The axis of the circular ring coincides with the axis of the separation cylinder 7. The outer side wall of the circular ring is fixed to the inner side wall of the upper shell 8. The inner side wall of the circular ring is close to the outer side wall of the separation cylinder 7. The gap between the inner side wall of the circular ring and the separation cylinder 7 is sealed by the second rotary seal 15. The area above the circular ring, between the outer side wall below the heavy phase outlet 10 of the separation cylinder 7 and the inner side wall of the upper shell 8, is the heavy phase collection weir 12. The light phase weir 11 is located above the first rotary seal 14, and the heavy phase collection port 13 is located on the upper shell between the first rotary seal 14 and the second rotary seal 15, and is in communication with the heavy phase collection weir 12. The first rotary seal 14 is arranged between the upper portion of the heavy phase outlet 10 of the separation cylinder 7 and the inner side wall of the upper shell 8, and the second rotary seal 15 is arranged between the lower portion of the heavy phase outlet 10 of the separation cylinder 7 and the heavy phase collection weir 12. The third rotary seal 16 is arranged between the gap of the rotary shaft 2 and the rotary shaft inlet and outlet of the lower shell 3. The separation cylinder 7 is provided with a baffle 17 near the feed inlet of the separation cylinder 7. The baffle 17 is located at the middle position of the lower portion of the separation cylinder 7. The baffle 17 is a radial baffle, which includes four blades with the same structure. The blades are uniformly distributed on a central axis, and extend outward along the radial direction of the central axis. The included angle between adjacent blades is 90°. The baffle 17 is fixed to the inner wall of the separation cylinder by the central axis and the fixed rod. After being fixed, the central axis is parallel to the horizontal plane, and the center of the central axis passes through the axis of the separation cylinder 7.

[0057] The centrifugal phase separation structure is located above the lower housing 3, and the driving device 1 is located below the lower housing 3; the lower end of the rotating shaft 2 is connected with the driving device 1, the upper end of the rotating shaft 2 is communicated with the separation cylinder feed inlet, and the rotating disc mounting section 201 and the liquid inlet 203 are located in the lower housing 3. Each rotating disc 4 is arranged alternately with each fixed ring 5, and the fixed ring 5 is located between adjacent rotating discs 4, that is, one fixed ring 5 is arranged between every two adjacent rotating discs 4. The axis of the lower housing 3 is perpendicular to the horizontal plane, and the axes of the upper housing 8, each rotating disc 4, each fixed ring 5, the rotating shaft 2 and the separation cylinder 7 all coincide with the axis of the lower housing 3. There are gaps between the fixed ring 5 and the rotating shaft 2, between the rotating disc 4 and the inner side wall of the lower housing 3, and between the adjacent rotating discs 4 and the fixed ring 5.

[0058] The rotating micro-reactor is supported and fixed by the support frame, and the driving device 1 is also supported and fixed by the support frame, so as to ensure the position stability of the rotating shaft 2 during the operation of the rotating micro-reactor.

[0059] More specifically:

[0060] The diameter of the rotating disc 4 is 4 cm, and the thickness of the rotating disc 4 is 5 mm; the ring width of the fixed ring 5 is 1.6 cm, and the thickness of the fixed ring 5 is 5 mm; the inner diameter of the lower housing 3 is 5 cm; the diameter of the rotating disc mounting section 201 and the material conveying section 202 of the rotating shaft 2 is 8 mm, and the hole diameter of the liquid inlet 203 is 0.5 mm. That is, the distance between the side wall of the rotating disc 4 and the inner side wall of the lower housing 3 is 5 mm, and the distance between the inner side wall of the fixed ring 5 and the outer wall of the rotating shaft 2 is 5 mm. The distance between the uppermost rotating disc 4 and the upper end of the lower housing 3 is 2 cm, and the distance between the lowermost rotating disc 4 and the lower end of the lower housing 3 is 1 cm; the distance between each fixed ring 5 and the rotating disc 4 adjacent to and above the fixed ring 5 in the axis direction of the rotating shaft 2 is 0.5 mm, and the distance between each fixed ring 5 and the rotating disc 4 adjacent to and below the fixed ring 5 in the axis direction of the rotating shaft 2 is 1 mm. The channel inner diameter of the mixed feed inlet 6 is 5 mm.

[0061] The inner diameter of the separation cylinder 7 is 2.5 cm, the height of the separation cylinder 7 is 6 cm, the width of the annular gap formed between the inner side wall of the upper housing 8 and the outer side wall of the separation cylinder 7 is 1 cm, and the distance between the upper end surface of the separation cylinder 7 and the top of the upper housing 8 is 3 cm. The distance between the heavy phase outlet 10 and the upper end surface of the separation cylinder 7 is 1 cm, and the hole diameter of the heavy phase outlet 10 is 1 mm. The hole diameter of the light phase outlet 9 is 1 mm. The vertical distance between the distal end of the blade closest to the separation cylinder feed inlet in the baffle 17 and the separation cylinder feed inlet is 0.5 cm, and the distance between the distal end of the blade closest to the side wall of the separation cylinder 7 in the baffle 17 and the side wall of the separation cylinder 7 is 0.6 times the radius of the separation cylinder 7.

[0062] The material of the rotating shaft 2, the lower shell 3, the upper shell 8, the rotating disc 4, the fixed ring 5 and the separation cylinder 7 is duplex stainless steel. The driving device 1 is a driving motor, and the driving device 1 drives the rotating shaft 2 to drive the rotating disc 4 and the separation cylinder 7 to rotate.

[0063] Example 2

[0064] In this embodiment, a rotating micro-reactor is provided, which has substantially the same structure as the rotating micro-reactor of Example 1, and the only difference is that:

[0065] The number of the rotating discs 4 is 2, each rotating disc 4 has the same structure, and the number of the fixed rings 5 is 1; as shown in Figure 3 Each rotating disc 4 is provided with a plurality of annular grooves 18 on the upper and lower surfaces thereof, and the axes of all the grooves 18 coincide with the axis of the rotating disc 4.

[0066] The diameter of the rotating disc 4 is 25 cm, the thickness of the rotating disc 4 is 10 mm, the cross section of the groove 18 provided on the upper and lower surfaces of the rotating disc 4 is rectangular, the width of the groove 18 is 1.5 mm, the depth of the groove 18 is 1 mm, and the distance between adjacent grooves 18 is 3 mm; the ring width of the fixed ring 5 is 8 cm, the thickness of the fixed ring 5 is 10 mm; the inner diameter of the lower shell 3 is 27 cm; the diameter of the rotating disc mounting section 201 and the material conveying section 202 of the rotating shaft 2 is 2 cm, and the hole diameter of the liquid inlet 203 is 1 mm. That is, the distance between the side wall of the rotating disc 4 and the inner side wall of the lower shell 3 is 10 mm, and the distance between the inner side wall of the fixed ring 5 and the outer wall of the rotating shaft 2 is 45 mm. The distance between the uppermost rotating disc 4 and the upper end of the lower shell 3 is 4 cm, and the distance between the lowermost rotating disc 4 and the lower end of the lower shell 3 is 2 cm; the distance between each fixed ring 5 and the rotating disc 4 adjacent thereto and located above it in the axial direction of the rotating shaft 2 is 2 mm, and the distance between each fixed ring 5 and the rotating disc 4 adjacent thereto and located below it in the axial direction of the rotating shaft 2 is 5 mm. The channel inner diameter of the mixed feed inlet 6 is 10 mm.

[0067] The inner diameter of the separation cylinder 7 is 15 cm, the height of the separation cylinder 7 is 30 cm, the width of the annular gap between the inner side wall of the upper shell 8 and the outer side wall of the separation cylinder 7 is 2.5 cm, and the distance between the upper end surface of the separation cylinder 7 and the top of the upper shell 8 is 3 cm. The distance between the heavy phase outlet 10 and the upper end surface of the separation cylinder 7 is 0.5 cm, and the hole diameter of the heavy phase outlet 10 is 2 mm. The hole diameter of the light phase outlet 9 is 2 mm. The vertical distance between the distal end of the vane closest to the separation cylinder inlet in the baffle 17 and the separation cylinder inlet is 0.5 cm, and the distance between the distal end of the vane closest to the side wall of the separation cylinder 7 in the baffle 17 and the side wall of the separation cylinder 7 is 0.5 times the radius of the separation cylinder 7.

[0068] Example 3

[0069] In this embodiment, a rotating microreactor is provided, which has substantially the same structure as the rotating microreactor of Example 1, except that:

[0070] The mixing inlet 6 is a Y-shaped mixing inlet; the number of rotating discs 4 is 10, each rotating disc 4 has the same structure, and the number of fixed rings 5 is 9; as shown in Figure 3 Each rotating disc 4 is provided with a plurality of annular grooves 18 on the upper and lower surfaces thereof, and the axes of all the grooves 18 coincide with the axis of the rotating disc 4.

[0071] The diameter of the rotating disc 4 is 100 cm, the thickness of the rotating disc 4 is 15 mm, the cross section of the groove 18 provided on the upper and lower surfaces of the rotating disc 4 is rectangular, the width of the groove 18 is 5 mm, the depth of the groove 18 is 2.5 mm, and the distance between adjacent grooves 18 is 5 mm; the ring width of the fixed ring 5 is 40 cm, and the thickness of the fixed ring 5 is 15 mm; the inner diameter of the lower shell 3 is 110 cm; the diameters of the rotating disc mounting section 201 and the material conveying section 202 of the rotating shaft 2 are both 10 cm, and the hole diameter of the liquid inlet 203 is 10 mm. That is, the distance between the side wall of the rotating disc 4 and the inner side wall of the lower shell 3 is 5 cm, and the distance between the inner side wall of the fixed ring 5 and the outer wall of the rotating shaft 2 is 10 cm. The distance between the uppermost rotating disc 4 and the upper end of the lower shell 3 is 5 cm, and the distance between the lowermost rotating disc 4 and the lower end of the lower shell 3 is 3 cm; the distance between each fixed ring 5 and the rotating disc 4 adjacent thereto and located above it in the axial direction of the rotating shaft 2 is 15 mm, and the distance between each fixed ring 5 and the rotating disc 4 adjacent thereto and located below it in the axial direction of the rotating shaft 2 is 30 mm. The channel inner diameter of the mixing inlet 6 is 15 mm.

[0072] The separator 7 has an inner diameter of 75 cm and a height of 150 cm. The width of the annular gap formed between the inner wall of the upper shell 8 and the outer wall of the separator 7 is 10 cm. The distance between the upper end face of the separator 7 and the top of the upper shell 8 is 8 cm. The distance between the heavy phase outlet 10 and the upper end face of the separator 7 is 10 cm, and the orifice diameter of the heavy phase outlet 10 is 10 mm. The orifice diameter of the light phase outlet 9 is 10 mm. The vertical distance between the tip of the blade closest to the separator inlet in the baffle 17 and the separator inlet is 5 cm. The distance between the tip of the blade closest to the side wall of the separator 7 and the side wall of the separator 7 is 0.5 times the radius of the separator 7.

[0073] Example 4

[0074] In this embodiment, a rotating microreactor is provided, the structure of which is basically the same as that of the rotating microreactor in Embodiment 1, with the only difference being:

[0075] There are 25 rotating disks 4, all with the same structure, and 24 fixed rings 5; for example... Figure 3 As shown, each rotating disk 4 has several annular grooves 18 on its upper and lower surfaces, and the axis of all grooves 18 coincides with the axis of the rotating disk 4.

[0076] The rotating disk 4 has a diameter of 25 cm and a thickness of 10 mm. The grooves 18 on the upper and lower surfaces of the rotating disk 4 have rectangular cross-sections, with a width of 1.5 mm and a depth of 1 mm. The distance between adjacent grooves 18 is 3 mm. The fixing ring 5 has a ring width of 7 cm and a thickness of 10 mm. The inner diameter of the lower housing 3 is 27 cm. The diameter of the rotating disk mounting section 201 and the material conveying section 202 of the rotating shaft 2 is 5 cm, and the diameter of the liquid inlet 203 is 5 mm. Specifically, the distance between the sidewall of the rotating disk 4 and the inner sidewall of the lower housing 3 is 10 mm, and the distance between the inner sidewall of the fixing ring 5 and the outer wall of the rotating shaft 2 is 45 mm. The distance between the uppermost rotating disk 4 and the upper end of the lower housing 3 is 6 cm, and the distance between the lowermost rotating disk 4 and the lower end of the lower housing 3 is 2 cm. The distance between each fixed ring 5 and the adjacent rotating disk 4 above it in the direction of the axis of rotation 2 is 2 mm, and the distance between each fixed ring 5 and the adjacent rotating disk 4 below it in the direction of the axis of rotation 2 is 5 mm. The inner diameter of the mixing inlet 6 is 20 mm.

[0077] The inner diameter of the separation cylinder 7 is 20 cm, the height of the separation cylinder 7 is 200 cm, the width of the annular gap between the inner side wall of the upper shell 8 and the outer side wall of the separation cylinder 7 is 2.5 cm, and the distance between the upper end surface of the separation cylinder 7 and the top of the upper shell 8 is 10 cm. The distance between the heavy phase outlet 10 and the upper end surface of the separation cylinder 7 is 3 cm, and the aperture of the heavy phase outlet 10 is 10 mm. The aperture of the light phase outlet 9 is 10 mm. The vertical distance between the tip of the blade in the baffle 17 closest to the separation cylinder inlet and the separation cylinder inlet is 0.5 cm, and the distance between the tip of the blade in the baffle 17 closest to the side wall of the separation cylinder 7 and the side wall of the separation cylinder 7 is 0.5 times the radius of the separation cylinder 7.

[0078] Example 5

[0079] In this embodiment, a rotating microreactor is provided, which has substantially the same structure as the rotating microreactor of Example 1, except that:

[0080] The number of rotating discs 4 is 5, each rotating disc 4 has the same structure, and the number of fixed rings 5 is 4. As shown in Figure 3 The upper and lower surfaces of each rotating disc 4 are provided with a plurality of annular grooves 18, and the axes of all the grooves 18 coincide with the axis of the rotating disc 4. The baffle 17 is in the form of a radial baffle, which includes 8 blades of the same structure, each blade is uniformly distributed on a central axis, and each blade extends outward along the radial direction of the central axis, and the included angle between adjacent blades is 45°.

[0081] The diameter of the rotating disc 4 is 150 cm, the thickness of the rotating disc 4 is 50 mm, the cross section of the groove 18 provided on the upper and lower surfaces of the rotating disc 4 is rectangular, the width of the groove 18 is 10 mm, the depth of the groove 18 is 10 mm, and the distance between adjacent grooves 18 is 2 mm; the ring width of the fixed ring 5 is 70 cm, and the thickness of the fixed ring 5 is 50 mm; the inner diameter of the lower shell 3 is 170 cm; the diameters of the rotating disc mounting section 201 and the material conveying section 202 of the rotating shaft 2 are 20 cm, and the aperture of the liquid inlet 203 is 20 mm. That is, the distance between the side wall of the rotating disc 4 and the inner side wall of the lower shell 3 is 10 cm, and the distance between the inner side wall of the fixed ring 5 and the outer wall of the rotating shaft 2 is 5 cm. The distance between the uppermost rotating disc 4 and the upper end of the lower shell 3 is 10 cm, and the distance between the lowermost rotating disc 4 and the lower end of the lower shell 3 is 5 cm; the distance between each fixed ring 5 and the rotating disc 4 adjacent thereto and located above it in the axial direction of the rotating shaft 2 is 10 cm, and the distance between each fixed ring 5 and the rotating disc 4 adjacent thereto and located below it in the axial direction of the rotating shaft 2 is 10 cm. The channel inner diameter of the mixed feed inlet 6 is 40 mm.

[0082] The inner diameter of the separation cylinder 7 is 135 cm, the height of the separation cylinder 7 is 150 cm, the width of the annular gap between the inner side wall of the upper shell 8 and the outer side wall of the separation cylinder 7 is 5 cm, and the distance between the upper end surface of the separation cylinder 7 and the top of the upper shell 8 is 30 cm. The distance between the heavy phase outlet 10 and the upper end surface of the separation cylinder 7 is 10 cm, and the aperture of the heavy phase outlet 10 is 20 mm. The aperture of the light phase outlet 9 is 20 mm. The vertical distance between the distal end of the blade closest to the separation cylinder inlet in the flow baffle 17 and the separation cylinder inlet is 10 cm, and the distance between the distal end of the blade closest to the side wall of the separation cylinder 7 in the flow baffle 17 and the side wall of the separation cylinder 7 is 0.4 times the radius of the separation cylinder 7.

[0083] Example 6

[0084] In this embodiment, the liquid-liquid extraction method of the present application is illustrated by taking phosphoric acid extraction as an example.

[0085] A mixture of tributyl phosphate and kerosene is used as the extractant, the volume ratio of tributyl phosphate to kerosene in the extractant is 8:2, and an aqueous phosphoric acid solution with a P2O5 mass content of 46% is used as the extractee. The rotary microreactor in Example 1 is used. The extractant is contained in the extractant storage tank 19, the extractant storage tank 19 is connected to one inlet of the T-shaped mixed inlet through a pipe and a first delivery pump 20, the extractee is contained in the extractee storage tank 21, the extractee storage tank 21 is connected to the other inlet of the T-shaped mixed inlet through a pipe and a second delivery pump 22, as shown in FIG. 1, and the steps are as follows: Figure 5

[0086] ①Start the driving device of the rotary microreactor to drive the rotating shaft, the rotating disc and the separation cylinder to rotate around the axis of the rotating shaft at a speed of 1500 rpm.

[0087] ②The extractant and the extractee are continuously introduced into the lower shell through the T-shaped mixed inlet by the first delivery pump and the second delivery pump respectively, the volume flow rate of the extractant is controlled to be 250 mL / min, the volume flow rate of the extractee is controlled to be 50 mL / min, the liquid-liquid extraction reaction is carried out in the lower shell, then the extractant and the extractee are continuously introduced into the separation cylinder through the material conveying section of the rotating shaft for centrifugal phase separation, and the light phase and the heavy phase after phase separation are continuously discharged from the light phase outlet and the heavy phase outlet of the rotary microreactor respectively. After the rotary microreactor is continuously operated for 30 min, the mass fraction of P2O5 in the raffinate is detected according to the method of GB / T 23843-2009, and the extraction rate is calculated according to the following formula w The results show that the extraction rate of phosphoric acid in this embodiment is 65.4%.

[0088] w =​m 1 c 1- m 2 c 2) / m 1 c 1×100%

[0089] in the above formula, m 1 is the weight of the feed liquid to be extracted, c 1 is the mass fraction of P2O5 in the feed liquid to be extracted, m 2 is the weight of the raffinate phase, c 2 is the mass fraction of P2O5 in the raffinate phase.

[0090] Example 7

[0091] In this example, the liquid-liquid extraction method of the present application is illustrated by taking phosphoric acid extraction as an example.

[0092] A mixture of tri-butyl phosphate and kerosene is used as the extractant, the volume ratio of tri-butyl phosphate to kerosene in the extractant is 8:2, and an aqueous solution of phosphoric acid with a P2O5 mass content of 46% is used as the feed liquid to be extracted. The rotating micro-reactor in Example 2 is used. The extractant is filled in the extractant storage tank 19, the extractant storage tank 19 is connected to one inlet of the T-shaped mixed feed inlet through a pipe fitting via the first delivery pump 20, the feed liquid to be extracted is filled in the feed liquid storage tank 21, the feed liquid storage tank 21 is connected to the other inlet of the T-shaped mixed feed inlet through a pipe fitting via the second delivery pump 22, and the steps are as follows:

[0093] ① The driving device of the rotating micro-reactor is started to drive the rotating shaft to rotate the rotating disc and the separation cylinder around the axis of the rotating shaft at a speed of 1200 rpm.

[0094] ② The extractant and the feed liquid to be extracted are continuously fed into the lower housing through the T-shaped mixed feed inlet by the first delivery pump and the second delivery pump respectively, the volume flow rate of the extractant is controlled to be 300 mL / min, the volume flow rate of the feed liquid to be extracted is controlled to be 60 mL / min, the extractant and the feed liquid perform liquid-liquid extraction reaction in the lower housing, and then are continuously fed into the separation cylinder through the material delivery section of the rotating shaft to perform centrifugal phase separation, and the light phase and the heavy phase after phase separation are continuously discharged from the rotating micro-reactor through the light phase outlet and the heavy phase outlet respectively.

[0095] After the rotating micro-reactor is continuously operated for 30 min, the mass fraction of P2O5 in the raffinate phase is detected according to the method of GB / T 23843-2009, and the extraction rate is calculated according to the method in Example 6. w The results show that the extraction rate of phosphoric acid in this example is 65.3%.

[0096] Comparative Example 1

[0097] In the present comparative example, phosphoric acid extraction experiment was carried out in a beaker.

[0098] A mixture of tributyl phosphate and kerosene was used as the extractant, the volume ratio of tributyl phosphate to kerosene in the extractant was 8:2, and a phosphoric acid aqueous solution with a P2O5 mass content of 46% was used as the to-be-extracted feed liquid.

[0099] 1500 mL of the extractant and 300 mL of the to-be-extracted feed liquid were added to the beaker, and the material in the beaker was stirred at a speed of 1500 rpm at room temperature to carry out liquid-liquid extraction reaction, the stirring time was controlled to be 8 s, then the stirring was stopped, and phase separation was carried out after standing to obtain an extraction phase and a raffinate phase.

[0100] The mass fraction of P2O5 in the raffinate phase was detected according to the method of GB / T 23843-2009, and the extraction rate was calculated according to the method in Example 6. w The results show that the extraction rate of phosphoric acid in the present comparative example is 25.4%. At the same time, it is found in the experiment that 66 min is needed for phase separation after stopping stirring.

[0101] Comparative Example 2

[0102] In the present comparative example, phosphoric acid extraction experiment was carried out in a beaker.

[0103] A mixture of tributyl phosphate and kerosene was used as the extractant, the volume ratio of tributyl phosphate to kerosene in the extractant was 8:2, and a phosphoric acid aqueous solution with a P2O5 mass content of 46% was used as the to-be-extracted feed liquid.

[0104] 1500 mL of the extractant and 300 mL of the to-be-extracted feed liquid were added to the beaker, and the material in the beaker was stirred at a speed of 1500 rpm at room temperature to carry out liquid-liquid extraction reaction, the stirring time was controlled to be 30 min, then the stirring was stopped, and phase separation was carried out after standing to obtain an extraction phase and a raffinate phase.

[0105] The mass fraction of P2O5 in the raffinate phase was detected according to the method of GB / T 23843-2009, and the extraction rate was calculated according to the method in Example 6. w The results show that the extraction rate of phosphoric acid in the present comparative example is 65.1%. At the same time, it is found in the experiment that 82 min is needed for phase separation after stopping stirring.

[0106] Compared with the method of directly extracting the extractant and the feed liquid under stirring, the method of the present application can significantly shorten the phase separation time. Meanwhile, in order to achieve the same extraction rate, under the flow conditions of Example 7, the residence time of the extractant and the feed liquid in the shell is not more than 60 s, while the extractant and the feed liquid need to be stirred and mixed for 30 min in Comparative Example 2. This shows that the method of the present application can significantly shorten the extraction time and improve the extraction efficiency.

[0107] Comparative Example 3

[0108] In this comparative example, phosphoric acid extraction experiments were carried out in a T-shaped coil microchannel.

[0109] The T-shaped coil microchannel used in this comparative example has a microchannel width of 0.5 mm, a microchannel depth of 0.5 mm, and a microchannel length of 100 cm. A mixture of tributyl phosphate and kerosene was used as the extractant, and the volume ratio of tributyl phosphate to kerosene in the extractant was 8:2. An aqueous phosphoric acid solution with a P2O5 mass content of 46% was used as the feed liquid to be extracted.

[0110] The extractant and the feed liquid to be extracted were continuously fed into the T-shaped coil microchannel by a delivery pump, the volume flow rate of the extractant was controlled to be 1500 mL / min, and the volume flow rate of the feed liquid to be extracted was controlled to be 300 mL / min. The extractant and the feed liquid were subjected to liquid-liquid extraction reaction in the T-shaped coil microchannel, and then were continuously discharged from the T-shaped coil microchannel and collected in a collection tank for phase separation.

[0111] After the T-shaped coil microchannel was continuously operated for 30 min, the raffinate phase was taken and the mass fraction of P2O5 in the raffinate phase was detected according to the method of GB / T 23843-2009, and the extraction rate was calculated according to the method in Example 6. w The results show that the extraction rate of phosphoric acid in this comparative example is 33.7%. At the same time, it was found during the experiment that the material discharged from the T-shaped coil microchannel needed to be left standing for 14 min after entering the collection tank to achieve phase separation.

[0112] As can be seen from Example 7 and Comparative Example 3, the same liquid-liquid extraction of phosphoric acid is carried out using a microreactor, the method of the present application can not only effectively shorten the phase separation time, but also effectively improve the extraction rate under the same treatment capacity.

[0113] Example 8

[0114] In this example, the liquid-liquid extraction method of the present application is illustrated by taking phosphoric acid extraction as an example.

[0115] The mixture of tributyl phosphate and kerosene is used as the extractant, the volume ratio of tributyl phosphate to kerosene in the extractant is 8:2, and the aqueous solution of phosphoric acid with a P2O5 mass content of 46% is used as the to-be-extracted feed liquid. The rotating micro-reactor in Example 3 is adopted. The extractant is filled in the extractant storage tank 19, the extractant storage tank 19 is connected with one inlet of the Y-shaped mixed feed inlet through the pipe fitting and the first conveying pump 20, the to-be-extracted feed liquid is filled in the feed liquid storage tank 21, the feed liquid storage tank 21 is connected with the other inlet of the Y-shaped mixed feed inlet through the pipe fitting and the second conveying pump 22, as shown in Figure 5 FIG. 2, the steps are as follows:

[0116] ① The driving device of the rotating micro-reactor is started to drive the rotating shaft to rotate the rotating disc and the separation cylinder around the axis of the rotating shaft at a rotating speed of 1500 rpm.

[0117] ② The extractant and the to-be-extracted feed liquid are continuously introduced into the lower housing through the Y-shaped mixed feed inlet by the first conveying pump and the second conveying pump respectively, the volume flow rate of the extractant is controlled to be 30 m 3 / h, and the volume flow rate of the to-be-extracted feed liquid is controlled to be 6 m 3 / h, the extractant and the feed liquid perform liquid-liquid extraction reaction in the lower housing, and then are continuously introduced into the separation cylinder through the material conveying section of the rotating shaft to perform centrifugal phase separation, the light phase and the heavy phase after phase separation are continuously flowed out of the rotating micro-reactor through the light phase outlet and the heavy phase outlet respectively.

[0118] After the rotating micro-reactor is continuously operated for 30 min, the mass fraction of P2O5 in the raffinate is detected according to the method in GB / T 23843-2009, and the extraction rate is calculated according to the method in Example 6 w , and the results show that the extraction rate of phosphoric acid in this example is 63.9%.

[0119] Example 9

[0120] In this example, the liquid-liquid extraction method is illustrated by taking phosphoric acid extraction as an example.

[0121] The mixture of tributyl phosphate and kerosene is used as the extractant, the volume ratio of tributyl phosphate to kerosene in the extractant is 8:2, and the aqueous solution of phosphoric acid with a P2O5 mass content of 46% is used as the to-be-extracted feed liquid. The rotating micro-reactor in Example 4 is adopted. The extractant is filled in the extractant storage tank 19, the extractant storage tank 19 is connected with one inlet of the T-shaped mixed feed inlet through the pipe fitting and the first conveying pump 20, the to-be-extracted feed liquid is filled in the feed liquid storage tank 21, the feed liquid storage tank 21 is connected with the other inlet of the T-shaped mixed feed inlet through the pipe fitting and the second conveying pump 22, and the steps are as follows:

[0122] ①Start the driving device of the rotary micro-reactor to drive the rotating shaft to rotate the rotating disc and the separation cylinder around the axis of the rotating shaft at a rotating speed of 600 rpm.

[0123] ②The extractant and the liquid to be extracted are continuously introduced into the lower shell through the T-shaped mixing feed port by the first delivery pump and the second delivery pump respectively, the volume flow rate of the extractant is controlled to be 250 L / h, the volume flow rate of the liquid to be extracted is controlled to be 50 L / h, the extractant and the liquid to be extracted carry out liquid-liquid extraction reaction in the lower shell, and then are continuously introduced into the separation cylinder through the material conveying section of the rotating shaft to carry out centrifugal phase separation, and the light phase and the heavy phase after phase separation are continuously flowed out of the rotary micro-reactor through the light phase outlet and the heavy phase outlet respectively.

[0124] After the rotary micro-reactor is continuously operated for 30 min, the mass fraction of P2O5 in the raffinate phase is detected according to the method of GB / T 23843-2009, and the extraction rate is calculated according to the method in Embodiment 6. w The results show that the extraction rate of phosphoric acid in this embodiment is 64.1%.

[0125] Embodiment 10

[0126] In this embodiment, the liquid-liquid extraction method is illustrated by taking phosphoric acid extraction as an example.

[0127] The mixture of tributyl phosphate and kerosene is used as the extractant, the volume ratio of tributyl phosphate to kerosene in the extractant is 8:2, and the aqueous solution of phosphoric acid with a P2O5 mass content of 46% is used as the liquid to be extracted. The rotary micro-reactor in Embodiment 5 is used. The extractant is contained in the extractant storage tank 19, the extractant storage tank 19 is connected with the T-shaped mixing feed port through the pipe fitting and the first delivery pump 20, the liquid to be extracted is contained in the liquid storage tank 21, the liquid storage tank 21 is connected with the T-shaped mixing feed port through the pipe fitting and the second delivery pump 22, and the steps are as follows:

[0128] ①Start the driving device of the rotary micro-reactor to drive the rotating shaft to rotate the rotating disc and the separation cylinder around the axis of the rotating shaft at a rotating speed of 500 rpm.

[0129] ②The extractant and the liquid to be extracted are continuously introduced into the lower shell through the T-shaped mixing feed port by the first delivery pump and the second delivery pump respectively, the volume flow rate of the extractant is controlled to be 60 m 3 / h, the volume flow rate of the liquid to be extracted is controlled to be 12 m 3 / h, the extractant and the liquid to be extracted carry out liquid-liquid extraction reaction in the lower shell, and then are continuously introduced into the separation cylinder through the material conveying section of the rotating shaft to carry out centrifugal phase separation, and the light phase and the heavy phase after phase separation are continuously flowed out of the rotary micro-reactor through the light phase outlet and the heavy phase outlet respectively.

[0130] After the rotary microreactor is continuously operated for 30 min, the mass fraction of P2O5 in the raffinate phase is detected according to the method of GB / T 23843-2009, and the extraction rate is calculated according to the method in Example 6 w The results show that the extraction rate of phosphoric acid in this example is 63.5%.

[0131] It can be known from Examples 6-10 that the extraction rates of phosphoric acid in Examples 6-10 are at a basically equivalent level, which shows that the same liquid-liquid extraction reaction is carried out after the rotary microreactor is scaled up, and the scaling up of the microreactor does not cause obvious adverse effects on the extraction rate. This shows that the rotary microreactor provided by the application has the characteristics of easy industrial scaling up.

Claims

1. A rotating microreactor comprising a drive device (1), a rotating shaft (2), a housing, characterized in that The device also comprises a rotating disc (4), a fixed ring (5) and a centrifugal phase separation structure, and the shell comprises a lower shell (3) and an upper shell (8); The rotating shaft (2) is composed of a rotating disc mounting section (201) and a material conveying section (202) which are connected to each other, and the material conveying section (202) is provided with a liquid inlet (203) and is open at the end; the lower shell (3) is a cylinder with both ends closed, and the lower shell (3) is provided with a mixing feed inlet (6), a rotating shaft inlet and a rotating shaft outlet, and the mixing feed inlet (6) is located at the bottom of the lower shell (3); the rotating disc (4) is N in number, and the fixed ring (5) is N-1 in number, wherein N is an integer greater than or equal to 2, each rotating disc (4) is horizontally arranged on the rotating disc mounting section (201), and each fixed ring (5) is horizontally arranged on the inner side wall of the lower shell (3); The centrifugal phase separation structure is located above the lower shell (3), and the centrifugal phase separation structure comprises a separation cylinder (7) and an upper shell (8) covering the separation cylinder (7), and the bottom center of the separation cylinder (7) is provided with a separation cylinder feed inlet; the lower end of the rotating shaft (2) is connected with a driving device (1) located below the lower shell (3), the upper end of the rotating shaft (2) is in communication with the separation cylinder feed inlet, the rotating disc mounting section (201) and the liquid inlet (203) are located in the lower shell (3); each rotating disc (4) and each fixed ring (5) are arranged alternately; the axis of the lower shell (3) is perpendicular to the horizontal plane, and the axes of the rotating disc (4), the fixed ring (5), the rotating shaft (2) and the separation cylinder (7) all coincide with the axis of the lower shell (3); there are gaps between the fixed ring (5) and the rotating shaft (2), between the rotating disc (4) and the inner side wall of the lower shell (3), and between adjacent rotating discs (4) and fixed rings (5); The separation cylinder (7) is a cylinder with both ends closed, the upper end surface of the separation cylinder (7) is provided with a light phase outlet (9), and the upper part of the side wall of the separation cylinder (7) is provided with a heavy phase outlet (10); the lower end of the upper shell (8) is fixed to the top of the lower shell (3), there is a gap between the inner wall of the upper shell (8) and the separation cylinder (7), the upper shell (8) is provided with a light phase weir (11), a heavy phase collection weir (12) and a heavy phase collection port (13); a first rotary sealing element (14) is arranged between the upper side wall of the upper shell (8) and the upper side of the heavy phase outlet (10), and a second rotary sealing element (15) is arranged between the heavy phase collection weir (12) and the lower side of the heavy phase outlet (10); third rotary sealing elements (16) are arranged at the gaps between the rotating shaft (2) and the rotating shaft inlet and the rotating shaft outlet of the lower shell (3); The distance between the inner side wall of the fixed ring (5) and the outer wall of the rotating shaft (2) is 5-45 mm, the distance between the side wall of the rotating disc (4) and the inner side wall of the lower shell (3) is 5-10 mm, and the distance between adjacent rotating discs (4) and fixed rings (5) in the axis direction of the rotating shaft (2) is 0.5-5 mm; the upper surface or / and the lower surface of the rotating disc is provided with a plurality of annular or spiral grooves (18).

2. The rotating microreactor according to claim 1, characterized in that The heavy phase collection weir (12) is arranged on the inner side wall of the upper shell (8), and is arranged around the separation cylinder (7) below the heavy phase outlet (10).

3. The rotating microreactor of claim 1, wherein, The separation cylinder (7) is provided with a flow baffle (17) near the separation cylinder inlet.

4. The rotating microreactor according to any one of claims 1 to 3, characterized in that The distance between the fixed ring (5) and the adjacent rotating disc (4) above it in the axial direction of the rotating shaft (2) is 0.4-1 times the distance between the fixed ring (5) and the adjacent rotating disc (4) below it in the axial direction of the rotating shaft (2).

5. The rotating microreactor according to any one of claims 1 to 3, characterized in that The thickness of the rotating disc (4) is 5-50 mm, the thickness of the fixed ring (5) is 5-50 mm, and the diameter of the rotating disc (4) is 4-150 cm.

6. The rotating microreactor according to any one of claims 1 to 3, characterized in that N is an integer between 2 and 25.

7. The rotating microreactor according to any one of claims 1 to 3, characterized in that The ratio of the inner diameter of the separation cylinder (7) to the diameter of the rotating disc (4) is (0.6-0.9):1, and the ratio of the height of the separation cylinder (7) to the diameter of the rotating disc (4) is (1-8):

1.

8. A liquid-liquid extraction method characterized by, The use of the rotating microreactor according to any one of claims 1-7 comprises the following steps: ①Start the driving device (1) to drive the rotating shaft (2) to rotate the rotating disc (4) and the separation cylinder (7) at a speed of 500-3000 rpm; ②The extractant and the liquid to be extracted are continuously introduced into the lower shell (3) from the mixed feed inlet (6), and the extractant and the liquid are subjected to liquid-liquid extraction reaction in the lower shell (3), and then continuously introduced into the separation cylinder (7) from the material conveying section (202) of the rotating shaft (2) for centrifugal phase separation, and the light phase and the heavy phase after phase separation are continuously discharged from the light phase weir (11) and the heavy phase collection port (13) respectively.

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