Feed premixing intensified mass transfer annular centrifugal extractor

Abstract

The application relates to an annular-gap type centrifugal extractor with pre-mixed and intensified mass transfer of feed, belonging to the technical field of extraction devices. The annular-gap type centrifugal extractor comprises an outer shell, a rotating drum and a rotating shaft coaxially arranged in the outer shell, a driving device arranged at the top end of the outer shell, the driving device being used for driving the rotating shaft to rotate the rotating drum in the outer shell, the rotating drum being used for realizing the separation of heavy phase and light phase, an annular-gap type feeding cavity arranged between the outer shell and the rotating drum, a material guiding hole arranged at the bottom of the rotating drum and communicated with the annular-gap type feeding cavity, a feeding end of the annular-gap type feeding cavity arranged on the side wall of the outer shell, and a micro-disperser arranged at the feeding end of the annular-gap type feeding cavity, liquid-liquid two phases which are not mutually soluble entering the micro-disperser from two feeding ports of the micro-disperser. The annular-gap type centrifugal extractor has the advantages of simple structure, pre-dispersion of liquid-liquid two phases which are not mutually soluble, intensified two-phase mass transfer, increased two-phase contact area, accelerated phase interface renewal rate, reduced mass transfer resistance, improved mass transfer efficiency and separation effect of the annular-gap type centrifugal extractor, and the like.

Description

Technical Field

[0001] This invention relates to the field of extraction apparatus technology, and more specifically, to an annular centrifugal extractor with feed premixing and enhanced mass transfer. Background Technology

[0002] In many industrial fields such as chemical engineering, pharmaceuticals, metallurgy, and environmental protection, liquid-liquid extraction, as a highly efficient separation and purification technology, is widely used in key processes such as raw material refining, product separation, and pollutant treatment. Its core principle is to utilize the difference in solubility of different components in a mixture in two immiscible (or slightly soluble) solvents to achieve the selective separation and enrichment of the target components. As industrial production develops towards higher efficiency, energy conservation, and refinement, increasingly higher demands are being placed on the separation efficiency, processing capacity, operational stability, and adaptability of liquid-liquid extraction equipment.

[0003] Annular centrifugal extractors, as highly efficient liquid-liquid extraction devices, demonstrate unique application value in processing easily emulsified systems, difficult-to-separate systems, and materials sensitive to residence time, thanks to their significant advantages such as high centrifugal force field strength, fast mass transfer rate, short residence time, and small footprint. Their core structure typically includes key components such as a rotating drum, a fixed cylinder, a feeding device, a light phase outlet, and a heavy phase outlet. During operation, the high-speed rotation of the drum generates a powerful centrifugal force, enabling rapid stratification and mass transfer of two liquid phases with different densities within the annular channel.

[0004] However, existing annular centrifugal extractors still face the challenge of improving mass transfer efficiency in practical applications, especially when processing high-viscosity materials, systems with low partition coefficients, or requiring high separation purity. A deeper analysis reveals that the main reason lies in the flawed feeding method of existing equipment: most annular centrifugal extractors employ a direct feeding mode, where the two phases to be processed are directly fed into the annular mass transfer zone, either separately or after mixing. Because the two phases are not sufficiently premixed before entering the centrifugal force field, the contact area between the two phases is small, and the phase interface renewal rate is slow.

[0005] Therefore, how to achieve sufficient premixing of two-phase materials by optimizing the feed structure without significantly increasing equipment energy consumption, volume, and operating costs, thereby increasing the contact area between the two phases, accelerating the phase interface renewal rate, reducing mass transfer resistance, and ultimately improving the mass transfer efficiency and separation effect of annular centrifugal extractors, has become a technical challenge that urgently needs to be solved by those skilled in the art. Based on this, developing an annular centrifugal extractor with efficient feed premixing capabilities and the ability to enhance the mass transfer process is of significant practical importance for promoting the development of liquid-liquid extraction technology and meeting the high-efficiency requirements of industrial production. Summary of the Invention

[0006] The purpose of this invention is to propose an annular gap centrifugal extractor with premixed feed to enhance mass transfer. This invention uses a micro-disperser to form immiscible liquid-liquid phases into micron-sized droplets for pre-dispersion, thus enhancing mass transfer. The material then passes through an annular gap feed chamber for further mass transfer. Furthermore, a baffle plate extends the mass transfer time, thereby increasing the contact area between the two phases, accelerating the phase interface renewal rate, and reducing mass transfer resistance. This ultimately improves the mass transfer efficiency and separation effect of the annular gap centrifugal extractor.

[0007] To achieve the above objectives, the present invention provides the following technical solution: An annular gap centrifugal extractor for enhanced mass transfer through premixed feeding includes a shell and a rotating drum and shaft coaxially disposed within the shell. A drive device is provided at the top of the shell and is connected to the rotating shaft to drive the rotating drum to rotate within the shell. The bottom of the rotating shaft is rotatably connected to the inner bottom wall of the shell. The rotating drum is used to separate the heavy phase and the light phase, and the separated heavy phase and light phase are discharged through the heavy phase outlet and light phase outlet respectively provided on the shell. An annular gap feeding chamber is provided between the shell and the rotating drum. The bottom of the rotating drum is provided with a guide hole communicating with the annular gap feeding chamber. The feed end of the annular gap feeding chamber is located on the side wall of the shell, and a micro-disperser is provided at the feed end of the annular gap feeding chamber. The feed end of the micro-disperser has two feed ports, and immiscible liquid-liquid phases enter the micro-disperser from the two feed ports respectively.

[0008] Preferably, the micro-disperser is provided with several micron-level channels, and the micro-dispersion and mass transfer of the liquid-liquid two phases are achieved by adopting at least one fluid flow mode among cross flow, impingement flow or shear dispersion flow in the micron-level channels, thereby achieving the purpose of feeding premixing and enhancing mass transfer.

[0009] Preferably, the size of the micron-level channel is 0.001~1.0 mm.

[0010] Preferably, the drive device is a variable frequency motor, and the output shaft of the variable frequency motor is connected to the rotating shaft through a coupling. This configuration allows the variable frequency motor to drive the rotating shaft to rotate at a set speed.

[0011] Preferably, the rotating drum has a heavy phase outlet at its top center and a light phase guide port on its upper side wall. The inner wall of the rotating drum has a light phase guide box connected to the light phase guide port. A heavy phase outlet channel is provided between the outer wall of the light phase guide box and the inner wall of the rotating drum. The top of the light phase guide box is fixedly connected to the rotating shaft, and the bottom of the light phase guide box has a light phase outlet coaxial with the rotating shaft. This configuration allows the rotating drum to rotate via the rotating shaft, so that after centrifugal separation, the denser liquid phase adheres tightly to the rotating drum and is sequentially led out through the heavy phase outlet channel and then through the heavy phase outlet to the heavy phase outlet for discharge. The less dense liquid phase, located near the rotating shaft, enters the light phase guide box through the light phase outlet and then through the light phase guide port to the light phase outlet for discharge.

[0012] Preferably, the upper end of the inner side of the outer casing is provided with a first guide cone and a second guide cone from top to bottom. The top end of the first guide cone is rotatably and sealingly connected to the outer wall of the top end of the rotating cylinder, and the bottom end of the first guide cone is fixedly connected to the inner wall of the outer casing. A heavy phase collection chamber is formed between the first guide cone and the outer casing, and the heavy phase outlet is connected to the bottom of the heavy phase collection chamber. The upper end of the second guide cone is correspondingly arranged to the lower edge of the light phase guide port, and the upper end of the second guide cone is rotatably and sealingly connected to the outer wall of the rotating cylinder. The lower end of the second guide cone is fixedly connected to the inner wall of the outer casing, and a light phase collection chamber is formed between the second guide cone and the outer casing. The light phase outlet is connected to the bottom of the light phase collection chamber. This arrangement is used to guide the heavy phase from the heavy phase inlet to the heavy phase outlet, and to guide the light phase from the light phase guide port to the light phase outlet.

[0013] Preferably, a baffle plate is provided inside the rotating drum. The baffle plate is fixedly connected to the lower part of the rotating shaft and is positioned above the feed guide hole. This arrangement is used to block the upward flow velocity of the two-phase solution, thereby further prolonging the mass transfer time between the two phases and accelerating the two-phase solution to the rotating shaft speed.

[0014] The present invention also includes other components that enable its normal use, all of which are conventional means in the art. In addition, devices or components not limited in the present invention, such as variable frequency motors, micro-dispersers, and rotating drums, all adopt existing technologies in the art.

[0015] The working principle of this invention is as follows: two immiscible liquid-liquid phases enter the micro-disperser from two feed ports respectively. After micro-dispersion, they are formed into micron-sized droplets for pre-dispersion to enhance the mass transfer between the two phases. The dispersed two-phase solution enters the annular feed chamber for further sufficient mass transfer. The two-phase material with sufficient mass transfer enters the rotating drum through the feed guide hole to achieve centrifugal phase separation. The denser liquid phase adheres tightly to the side wall of the rotating drum and is guided to the heavy phase outlet for discharge. The less dense liquid phase is located near the rotating shaft and is guided to the light phase outlet for discharge.

[0016] Compared with the prior art, the invention has the following beneficial effects: The invention has a simple structure and is easy to operate. It can enable the premixing of immiscible liquid-liquid two phases to enhance mass transfer, thereby increasing the contact area between the two phases, accelerating the phase interface renewal rate, reducing the mass transfer resistance, and thus improving the mass transfer efficiency and separation effect of the annular gap centrifugal extractor. Attached Figure Description

[0017] The invention will be further described below with reference to the accompanying drawings and embodiments: Figure 1 This is a schematic diagram of the overall structure of the present invention in Embodiment 1.

[0018] Figure 2 This is a top view of the connection structure between the light phase guide box and the rotating cylinder in Embodiment 1 of the present invention.

[0019] Figure 3 This is a schematic diagram of the connection structure between the first guide cone, the second guide cone, and the rotating cylinder in Embodiment 1 of the present invention. Detailed Implementation

[0020] The invention will now be clearly described in conjunction with the accompanying drawings and specific embodiments. This description is merely for illustrative purposes and is not intended to limit the invention. Any modifications, equivalent substitutions, or improvements made by those skilled in the art based on the embodiments of the invention without inventive effort to obtain all other embodiments should be included within the scope of protection of the invention.

[0021] Example 1 like Figure 1 As shown, this embodiment provides an annular gap centrifugal extractor with enhanced mass transfer through premixed feeding, including a shell 2 and a rotating drum 3 and a rotating shaft 4 coaxially disposed within the shell. A driving device 5 is provided at the top of the shell, and the driving device is connected to the rotating shaft to drive the rotating drum to rotate within the shell. The bottom of the rotating shaft is rotatably connected to the inner bottom wall of the shell. The rotating drum is used to separate the heavy phase and the light phase, and the separated heavy phase and light phase are discharged through the heavy phase outlet 6 and the light phase outlet 7 respectively provided on the shell. An annular gap feeding chamber 8 is provided between the shell and the rotating drum. The bottom of the rotating drum is provided with a guide hole 9 that communicates with the annular gap feeding chamber. The feed end of the annular gap feeding chamber is provided on the side wall of the shell, and a micro-disperser 1 is provided at the feed end of the annular gap feeding chamber. The feed end of the micro-disperser is provided with two feed ports 10, and the immiscible liquid-liquid phases enter the micro-disperser from the two feed ports respectively.

[0022] In this embodiment, the microdispersor is provided with several micron-level channels, and the micro-dispersion and mass transfer of the liquid-liquid two phases are achieved by adopting a cross-flow pattern within the micron-level channels, thereby achieving the purpose of enhanced mass transfer through feed premixing. The size of the micron-level channels is 0.001~1.0 mm.

[0023] Following the above embodiments, please refer to Figure 1 The drive device uses a variable frequency motor, and the output shaft of the variable frequency motor is connected to the rotating shaft through a coupling. This configuration allows the variable frequency motor to drive the rotating shaft to rotate at a set speed.

[0024] Specifically, such as Figure 1 and Figure 2 As shown, the top center of the rotating drum is provided with a heavy phase outlet 11, and the upper side wall of the rotating drum is provided with a light phase guide port 12. The inner wall of the rotating drum is provided with a light phase guide box 13 that communicates with the light phase guide port. A heavy phase outlet channel 14 is left between the outer side wall of the light phase guide box and the inner wall of the rotating drum. The top of the light phase guide box is fixedly connected to the rotating shaft, and the bottom of the light phase guide box is provided with a light phase outlet 15 that is coaxial with the rotating shaft. This configuration can drive the rotating drum to rotate through the rotating shaft, so that after the two phases of material in the rotating drum are separated by centrifugation, the denser liquid phase adheres tightly to the rotating drum and is led out through the heavy phase outlet channel and heavy phase outlet to the heavy phase outlet for discharge. The less dense liquid phase is located near the rotating shaft, enters the light phase guide box through the light phase outlet, and is then led out through the light phase guide port to the light phase outlet for discharge.

[0025] More specifically, such as Figure 1 and Figure 3 As shown, the upper part of the inner side of the outer shell is provided with a first guide cone 16 and a second guide cone 17 from top to bottom. The top end of the first guide cone is rotatably and sealingly connected to the outer wall of the top end of the rotating cylinder through an O-ring rubber seal 18, and the bottom end of the first guide cone is fixedly connected to the inner wall of the outer shell. A heavy phase collection chamber 19 is formed between the first guide cone and the outer shell, and the heavy phase outlet is connected to the bottom of the heavy phase collection chamber. The upper end of the second guide cone is correspondingly arranged to the lower edge of the light phase guide port, and the upper end of the second guide cone is rotatably and sealingly connected to the outer wall of the rotating cylinder through an O-ring rubber seal 20. The lower end of the second guide cone is fixedly connected to the inner wall of the outer shell, and a light phase collection chamber 21 is formed between the second guide cone and the outer shell, and the light phase outlet is connected to the bottom of the light phase collection chamber. This arrangement is used to guide the heavy phase from the heavy phase outlet to the heavy phase outlet, and to guide the light phase from the light phase guide port to the light phase outlet.

[0026] Following the above embodiments, please refer to Figure 1A baffle plate 22 is provided inside the rotating drum. The baffle plate is fixedly connected to the lower part of the rotating shaft and is positioned above the feed guide hole. This arrangement is used to block the upward flow velocity of the two-phase solution, thereby further prolonging the mass transfer time between the two phases and accelerating the two-phase solution to the rotating shaft speed.

[0027] The working principle of this invention is as follows: two immiscible liquid-liquid phases enter the micro-disperser from two feed inlets respectively. After micro-dispersion, they are formed into micron-sized droplets for pre-dispersion to enhance the mass transfer between the two phases. The dispersed two-phase solution enters the annular feed chamber for further sufficient mass transfer. With the help of the baffle plate, the mass transfer time between the two phases is further extended. The two-phase materials with sufficient mass transfer enter the rotating drum through the guide hole to achieve centrifugal phase separation. The denser liquid phase adheres tightly to the side wall of the rotating drum and is guided to the heavy phase outlet for discharge. The less dense liquid phase is located near the rotating shaft and is guided to the light phase outlet for discharge.

[0028] Example 2 The only difference between this embodiment and Embodiment 1 is that the liquid-liquid two-phase mass transfer is achieved in the micron-level channel by using an impinging flow mode.

[0029] Example 3 The only difference between this embodiment and Embodiment 1 is that the liquid-liquid two-phase mass transfer is achieved in the micron-level channel by adopting a shear-dispersion flow mode.

[0030] Through the above embodiments 1-3, it is possible to achieve feed premixing and enhanced mass transfer of immiscible liquid-liquid two phases, thereby improving the mass transfer efficiency of the equipment.

[0031] The above description is merely a preferred embodiment of the present invention and is not limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A premixed feed-enhanced mass transfer annular centrifugal extractor, comprising a shell and a rotating drum and a rotating shaft coaxially disposed within the shell, wherein a driving device is disposed at the top of the shell, the driving device being kinetically connected to the rotating shaft and used to drive the rotating shaft to rotate the rotating drum within the shell, the bottom of the rotating shaft being rotatably connected to the inner bottom wall of the shell, the rotating drum being used to separate the heavy phase and the light phase, and the separated heavy phase and light phase being discharged externally through a heavy phase outlet and a light phase outlet respectively disposed on the shell, characterized in that: An annular feeding chamber is provided between the outer shell and the rotating drum. The bottom of the rotating drum is provided with a guide hole that communicates with the annular feeding chamber. The feeding end of the annular feeding chamber is located on the side wall of the outer shell, and a micro-disperser is provided at the feeding end of the annular feeding chamber. The feeding end of the micro-disperser is provided with two feeding ports, and the immiscible liquid-liquid phases enter the micro-disperser from the two feeding ports respectively.

2. The annular gap centrifugal extractor with feed premixing and enhanced mass transfer according to claim 1, characterized in that: The micro-dispersor is provided with several micron-level channels, and the micro-dispersion and mass transfer of the liquid-liquid two phases are achieved by using at least one fluid flow mode among cross flow, impingement flow or shear dispersion flow within the micron-level channels.

3. The annular gap centrifugal extractor with enhanced mass transfer through premixed feed as described in claim 2, characterized in that: The size of the micron-level channel is 0.001~1.0 mm.

4. The annular gap centrifugal extractor with enhanced mass transfer through premixed feed as described in claim 1, characterized in that: The drive device uses a variable frequency motor, and the output shaft of the variable frequency motor is connected to the rotating shaft through a coupling.

5. The annular gap centrifugal extractor with enhanced mass transfer through premixed feed as described in claim 1, characterized in that: The top center of the rotating drum is provided with a heavy phase outlet, and the upper side wall of the rotating drum is provided with a light phase guide port. The inner wall of the rotating drum is provided with a light phase guide box that communicates with the light phase guide port. A heavy phase outlet channel is left between the outer side wall of the light phase guide box and the inner wall of the rotating drum. The top of the light phase guide box is fixedly connected to the rotating shaft, and the bottom of the light phase guide box is provided with a light phase outlet that is coaxial with the rotating shaft.

6. The annular gap centrifugal extractor with feed premixing and enhanced mass transfer according to claim 5, characterized in that: The upper part of the inner side of the outer shell is provided with a first guide cone and a second guide cone from top to bottom. The top end of the first guide cone is rotatably and sealingly connected to the outer wall of the top end of the rotating cylinder, and the bottom end of the first guide cone is fixedly connected to the inner wall of the outer shell. A heavy phase collection chamber is formed between the first guide cone and the outer shell. The heavy phase outlet is connected to the bottom of the heavy phase collection chamber. The upper end of the second guide cone is correspondingly set to the lower edge of the light phase guide port. The upper end of the second guide cone is rotatably and sealingly connected to the outer wall of the rotating cylinder. The lower end of the second guide cone is fixedly connected to the inner wall of the outer shell. A light phase collection chamber is formed between the second guide cone and the outer shell. The light phase outlet is connected to the bottom of the light phase collection chamber.

7. The annular gap centrifugal extractor with feed premixing and enhanced mass transfer according to claim 1, characterized in that: A baffle plate is provided inside the rotating drum. The baffle plate is fixedly connected to the lower part of the rotating shaft and is positioned above the material guide hole.

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