Foam separation device and method for high-gravity efficient foaming

Abstract

The invention discloses a supergravity efficient foaming foam separation device and method, and belongs to the field of chemical separation equipment. The device comprises a supergravity rotating packed bed, a foam rectifying tower and a foam stripping tower, the foam rectifying tower is connected with the top of the supergravity rotating packed bed; the foam stripping tower is connected with the bottom of the supergravity rotating packed bed; the bottom of the foam stripping tower and a gas inlet of the supergravity rotating packed bed are connected with a gas conveying pipeline; the gas conveying pipeline consists of a fan, a gas buffer tank, a gas valve and a gas flow meter which are connected in sequence; the supergravity rotating packed bed is connected with a liquid conveying pipeline, and the liquid conveying pipeline comprises a raw material liquid tank, a pump, a liquid valve and a liquid flowmeter which are connected in sequence. The problems of large and non-uniform bubbles, low mass transfer efficiency and low separation efficiency of traditional foam separation equipment are solved, the gas-liquid contact effective area is increased by utilizing a supergravity technology, the separation effect is greatly improved, and efficient separation of target substances is realized.

Description

Technical Field

[0001] The invention relates to a supergravity high-efficiency foaming foam separation device and method, belonging to the field of chemical separation equipment. Background Art

[0002] Foam separation technology is an effective method for separating and enriching trace substances. It is based on the principle of interfacial chemical surface adsorption and uses bubbles generated by ventilation bubbling as the separation medium to separate solutes or particles in the liquid phase. This technology is used for separation based on the difference in surface activity between various components in the solution. It has the advantages of simple equipment, low energy consumption, easy operation, low operating cost, high efficiency at low concentration, no pollution, and suitability for large-scale industrial production. In recent years, with the development of foam separation technology, the separation objects have expanded from solid minerals to metal ions, organic pollutants, biomolecules (such as proteins), enzymes, etc. It is one of the emerging separation technologies with great development prospects.

[0003] There are two necessary conditions for separation by foam separation technology: first, the substance to be separated needs to have surface activity or be able to combine with a certain type of surfactant substance, using bubbles as a medium to make the substance to be separated adsorbed on the foam. The adsorption of the surfactant on the interface changes the interfacial properties including surface tension, thereby affecting the foaming and stability of the foam; second, the liquid phase can produce a large number of microbubbles, and the substance to be separated is separated from the liquid phase with the help of bubbles and enriched at the top of the tower. The foam can be continuously collected from the top of the tower without violent collapse (the enriched substance can form a stable foam layer during the separation process). After the separation, defoaming treatment is carried out to obtain the enriched product. The entire mass transfer process includes two stages: one stage occurs in the bubbling zone, between the liquid phase and the bubble surface; the other stage occurs in the foam zone, on the bubble surface.

[0004] When the solute to be separated in the solution is a surfactant component, the solute can be enriched on the foam by using the foam formed by the gas in the solution, and then the foam is collected. After defoaming, a foam liquid with a higher solute content than the raw material liquid can be obtained. Surfactants are a class of compounds with a special amphiphilic structure, usually composed of two main parts: a hydrophilic group and a hydrophobic group. Its structure can cause the surfactant to aggregate on the surface, reduce the surface tension of the liquid, and cause the surfactant molecules to be oriented on the surface with the hydrophilic group located in the water phase and the hydrophobic group away from the water phase. When it exists in a system at a low concentration, it can significantly change the free energy properties of these surfaces (or interfaces). When the concentration exceeds the critical micelle concentration, the excess surfactant molecules exist in the main solution as molecular aggregates-micelles (Micelle) inside the solution. Foam separation is a method developed by utilizing the interface selective directional adsorption of surfactants. The process parameters involved in foam separation technology include feed concentration, solution pH, separation temperature, gas inlet velocity, liquid volume, gas distributor pore size, etc., among which improving the foam separation effect is the main goal.

[0005] Traditional foam separation equipment is a vertical single-stage foam separation column with the foam phase located above the liquid phase, no internal components added to the foam phase and the liquid phase, and no reflux device. The column body is generally a long cylinder of organic glass with a height-to-diameter ratio usually greater than 10, in order to reduce axial backmixing and provide sufficient gas-liquid contact and foam drainage time to obtain better foam separation effect. However, traditional foam separation equipment has certain limitations on the adsorption of target substances and foam drainage, and cannot achieve a good separation effect.

[0006] Chinese patent CN110240625A discloses a method for separating quinoa saponins and a foam separation device. The invention method uses foam separation technology to separate and extract quinoa saponins; the most preferred raw material liquid concentration is 0.5296 mg / mL, the temperature is 25°C, the ventilation flow rate is 22 mL / min, and the raw material liquid volume is 250 mL. Among them, the quinoa saponin enrichment ratio is 2.0-2.6, and the recovery rate is 42%-52%; the invention optimizes the process parameters (pH, temperature, gas flow, etc.) involved in the experiment to improve the foam separation effect.

[0007] Chinese patent CN109336945A discloses a method for water extraction and foam separation of tea saponin from tea cake, including water extraction of tea saponin, foam separation, repeated purification and other steps. The invention also relates to a foam separation device, including a raw material processing device, a foam processing device and a foam reflux device. The invention extracts tea saponin from tea cake powder by the foam separation device of the invention, wherein the tea saponin extraction rate is 13.86%, the tea saponin yield reaches 73.21%, and the concentration multiple reaches 2.15.

[0008] At present, foam separation equipment has certain limitations on the adsorption of target substances and foam drainage, and cannot achieve a good separation effect. Among them, there are the following deficiencies: (1) The bubbles in existing equipment are large and unevenly distributed, and the effective contact area between the target substance and the gas-liquid interface is limited, which directly affects the mass transfer rate and adsorption efficiency of the gas-liquid interface, resulting in poor separation effect; (2) There is still a contradiction between the enrichment ratio and the recovery rate, and the inverse proportional relationship is difficult to maintain; (3) The foam separation equipment with added internal components is relatively complex, with a large pressure drop, high processing cost, and limited application.

[0009] The traditional foam separation process has problems such as large and uneven bubbles, slow mass transfer efficiency, and low separation efficiency. Therefore, reducing the bubble size, improving the bubble morphology, and improving the mass transfer efficiency and separation efficiency are issues that need to be urgently addressed.

[0010] In order to achieve the above-mentioned object, the present invention proposes a foam separation device and method for supergravity high-efficiency foaming. Summary of the invention

[0011] In view of the problems existing in the current foam separation technology, such as large bubbles, slow mass transfer efficiency, low separation efficiency, etc., the present invention provides a supergravity high-efficiency foaming foam separation device and method.

[0012] The innovative features of the present invention are as follows: ① It is the first time that the ultra-gravity technology is applied to the field of foam separation, and the ultra-gravity foam separation technology is pioneered. A foam separation device with ultra-gravity high-efficiency foaming is independently developed; the use of ultra-gravity technology can greatly enhance the foam separation process; ultra-gravity technology can effectively improve the gas-liquid mass transfer efficiency. The high-speed rotating filler in the ultra-gravity field generates huge shear force. The liquid is torn into a micro-liquid state after multiple times and quickly contacts with the gas, which accelerates the frequency of gas-liquid surface renewal and the degree of liquid turbulence, increases the effective contact area of ​​the target substance at the gas-liquid interface, and greatly improves the interphase mass transfer rate. ② In the present invention, after the raw material liquid enters the ultra-gravity rotating packed bed, uniform sub-millimeter microbubbles can be quickly generated; the bubbles undergo several dispersion-aggregation processes, which strengthens the liquid phase adsorption process; and then directly contact with the gas, which greatly increases the effective contact area between the foam and the gas, accelerates the gas-liquid phase velocity, improves the surface adsorption capacity, has a high foaming rate, and quickly completes the gas-liquid mass transfer process; the surfactant can quickly form bubbles under the action of stirring due to its low surface tension; the surfactant forms bubbles more quickly under the action of the high-speed rotating filler, and the bubbles can be sheared into extremely small sizes, the specific surface area is increased, and the gas-liquid interface is continuously updated, thereby increasing the adsorption amount and improving the separation efficiency.

[0013] The invention provides a high-efficiency foaming foam separation device, comprising a high-gravity rotating packed bed, a foam distillation tower and a foam stripping tower; the foam distillation tower is connected to the top of the high-gravity rotating packed bed; the foam stripping tower is connected to the bottom of the high-gravity rotating packed bed; The bottom of the foam distillation tower and the gas inlet of the ultra-gravity rotating packed bed are both connected to a gas delivery pipeline, the gas delivery pipeline is composed of a blower, a gas buffer tank, a gas valve, and a gas flow meter connected in sequence, and the gas delivery pipeline is connected to the gas inlet of the foam distillation tower; The ultra-gravity rotating packed bed is connected to a liquid delivery pipeline, and the liquid delivery pipeline comprises a raw material liquid tank, a pump, a liquid valve and a liquid flow meter which are connected in sequence.

[0014] Furthermore, the ultra-gravity rotating packed bed includes a rotor, packing, a shell, a motor, and a liquid distributor. The lower side of the shell is provided with a gas inlet, the top is provided with a liquid inlet and a foam outlet, and the bottom is provided with a liquid outlet; various packings are installed in the rotor, the bottom of the rotor is connected to the motor, and is driven to rotate by the motor; the foam outlet of the ultra-gravity rotating packed bed is connected to the gas inlet of the foam distillation tower, and its liquid outlet is connected to the foam outlet of the foam distillation tower; the liquid inlet is connected to the liquid delivery pipeline, and the liquid is delivered to the inside of the packing through the liquid distributor.

[0015] Furthermore, the foam distillation tower is cylindrical, with an elbow at the top, the elbow is semicircular, and the other end of the elbow is connected to an anti-overflow hood, wherein the ratio of the bottom diameter of the anti-overflow hood to the upper diameter is 1:1~10:1, and the anti-overflow hood is straight or gradually expanded, and its shape is determined by the diameter ratio; the anti-overflow hood is connected to a foam catcher; a reflux pipe is arranged below one side of the foam distillation tower, and a part of the reflux liquid in the foam catcher flows into the foam distillation tower again, and the other part enters the defoaming liquid collecting tank; a diverter valve is arranged on the liquid outlet pipe of the foam catcher, and the diverter valve can be adjusted manually or automatically, and the diversion ratio of the reflux liquid and the defoaming liquid is controlled by adjusting the opening of the valve, and a flow meter is installed on each of the pipes where the reflux liquid enters the foam distillation tower and the defoaming liquid enters the collecting tank, and the flow of the reflux liquid and the defoaming liquid is monitored in real time, and the opening of the valve is accurately adjusted to realize dynamic control of the liquid flow. If conditions permit, an automatic control system can be installed to automatically adjust the opening of the diverter valve according to the preset diversion ratio. For example, when the liquid reaches a certain reflux volume, the system automatically reduces the reflux volume and increases the amount of defoaming liquid.

[0016] Furthermore, the structure of the overflow prevention cover is: a bowl-shaped structure with upper and lower openings, the upper opening is connected to an elbow, and the lower opening is connected to a foam catcher to prevent foam from overflowing; the structure of the foam catcher is: the body of the device is cylindrical, an ultrasonic device is installed on one side of the interior, and an ultrasonic rod is extended into the interior to break the foam; a needle-shaped foam breaker is arranged at the bottom and the side, and the needle-shaped foam breaker is a mace-shaped structure with sharp thorns arranged upward; the ultrasonic rod and the needle-shaped foam breaker can be used simultaneously or separately, and the size of the needle-shaped foam breaker is determined according to the size of the foam catcher.

[0017] Furthermore, the body of the foam distillation tower is cylindrical, the top foam outlet is connected to the liquid outlet of the supergravity rotating packed bed, the gas blown out by the fan enters the tower from the gas inlet, and a gas distributor is arranged above the gas inlet; the residual liquid outlet is arranged on the side of the bottom of the tower and connected to the residual liquid collection tank.

[0018] Furthermore, the residual liquid collecting tank is connected to the liquid inlet of the high gravity rotating packed bed.

[0019] Furthermore, the filler of the high gravity rotating packed bed is at least one or more combinations of ball ring fillers, wire mesh fillers, spherical fillers, and arc saddle fillers, and the type of filler can be replaced.

[0020] Furthermore, the height-to-diameter ratio of the foam distillation tower and the foam stripping tower is in the range of 5-50.

[0021] The present invention provides a foam separation method of supergravity high-efficiency foaming. In the above-mentioned foam separation device of supergravity high-efficiency foaming, a raw material liquid is foamed by a supergravity rotating packed bed to generate a foam phase and a liquid phase. The foam phase enters a foam distillation tower through a gas outlet of the rotating packed bed, and a high-concentration target substance is collected at the top of the foam distillation tower; the liquid phase enters a foam stripping tower due to gravity for further foam separation, and the remaining liquid phase component is obtained at the bottom of the foam stripping tower.

[0022] The above-mentioned method for separating foam by high-efficiency supergravity foaming comprises the following steps: The raw material liquid is placed in a raw material liquid storage tank, a certain speed is set for the supergravity rotating packed bed, the motor is started, and the liquid in the raw material liquid storage tank is pumped into the supergravity rotating packed bed from the liquid inlet through the liquid delivery pipe, and is sprayed radially through the inner edge of the packing by the liquid distributor. At the same time, the fan is started to blow in gas, which passes through the gas buffer tank and adjusts the gas flow meter. When the gas speed tends to be stable, the gas is divided into two routes to enter the foam distillation tower and the supergravity rotating packed bed respectively. One gas pipeline enters the foam distillation tower from the gas inlet through the gas distributor and rises to the rotating packed bed. The other gas pipeline enters the supergravity rotating packed bed from the gas inlet, and then the two gases are collected in the rotating packed bed. At this time, the raw material liquid and gas are fully in contact in the rotating packed bed, generating a large number of evenly distributed sub-millimeter microbubbles. Under the action of centrifugal force, the bubbles are thrown between the outer edge of the packing and the inner wall of the shell. Due to the effect of gas pressure, the bubbles enter the foam distillation tower from the foam outlet to realize the foam separation process. The foam enters the foam catcher through the overflow cover. Most of the bubbles form defoaming liquid in the foam catcher through the ultrasonic rod or needle-shaped foam breaker. The diversion ratio of the reflux liquid and the defoaming liquid is controlled by adjusting the opening of the diversion valve on the liquid outlet pipe of the foam catcher, wherein a part of the defoaming liquid enters the defoaming liquid collecting tank, and the other part of the defoaming liquid is introduced into the foam distillation tower from the side port of the foam distillation tower as the reflux liquid; at the same time, during the foam separation process, the foam interstitial liquid and the reflux liquid flow into the supergravity rotating packed bed due to gravity and are discharged through the liquid outlet and transferred to the foam distillation tower, and the continuously rising gas and liquid are separated from the foam again, and the foam is transferred into the supergravity rotating packed bed again under the action of the gas, and finally returns to the foam catcher, until the foam no longer overflows, the valve of the reflux pipe is closed, and the remaining defoaming liquid is all transferred to the defoaming liquid collecting tank, and the residual liquid in the foam distillation tower is introduced into the residual liquid collecting tank, and finally the residual liquid is collected.

[0023] In the above method, the gas-liquid contact mode is one of cross-flow, counter-flow or parallel flow, the hypergravity factor is 5-120; the gas is at least one or more of air, carbon dioxide, nitrogen, oxygen or inert gas.

[0024] In the above separation method, the reflux ratio of the defoaming liquid, the height of the stripping section, the height of the rectifying section and the height of the packing are determined according to the foam rising speed, the gas-liquid flow rate and the separation effect; that is, the reflux ratio is controlled by controlling factors such as the gas flow rate, the liquid flow rate, the concentration of the raw material liquid, and the pH value, and finally a suitable reflux ratio is selected during operation to ensure that the process can be operated continuously; The reflux ratio R refers to the ratio of the reflux liquid flow rate L in the defoaming liquid returning to the tower to the liquid flow rate D in the defoaming liquid collecting tank, that is, R=L / D; the gas flow rate and liquid flow rate need to be analyzed and determined based on the specific equipment, and the raw liquid concentration and pH need to be determined based on the target substance and the exploration experiment. If the target substance is a surfactant, the raw liquid concentration needs to be kept below the critical micelle concentration.

[0025] Beneficial effects of the present invention: (1) The ultra-gravity high-efficiency foaming foam separation device and method provided by the present invention solve the problems faced by traditional foam separation equipment, such as large and uneven bubbles, slow mass transfer efficiency, and low separation efficiency; and achieve high-efficiency separation performance of the target substance; (2) The present invention utilizes ultra-gravity technology to increase the effective area of ​​gas-liquid contact, thereby achieving the advantage of fully adsorbing the target substance on the interface to achieve sub-millimeter microbubbles, while also stabilizing the bubble morphology, effectively increasing the contact time between the bubbles and the target substance in the main liquid phase, and greatly improving the separation effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the foam separation device of the present invention for high-efficiency supergravity foaming; Figure 2 It is a schematic diagram of a foam distillation tower in the device of the present invention; Figure 3 It is a schematic diagram of a foam distillation tower in the device of the present invention; Figure 4 It is a structural diagram of the anti-overflow cover in the device of the present invention; Figure 5 for Figure 4 A top view of the middle overflow hood; Figure 6 It is the reflux and defoaming liquid collecting unit of the present invention; Figure 7 It is a structural diagram of the foam catcher in the device of the present invention; Figure 8 for Figure 7 A top view of the internal structure of the middle foam catcher; Fig. 9 This is a diagram of the internal structure of the ultra-gravity rotating packed bed of the present invention.

[0027] In the figure: 1, raw liquid storage tank; 2, pump; 3, liquid valve; 4, liquid flow meter; 5, supergravity rotating packed bed; 6, foam distillation tower; 7, fan; 8, gas buffer tank; 9, gas valve; 10, gas flow meter; 11, foam distillation tower; 12, residual liquid collecting tank; 13, overflow cover; 14, ultrasonic rod; 15, foam catcher; 16, diverter valve; 17, defoaming liquid collecting tank; 18, ultrasonic disperser; 19, motor; 601, foam distillation tower gas inlet; 602, foam distillation tower side port; 1101, foam distillation tower gas inlet; 1102, gas distributor; 1103, foam distillation tower residual liquid outlet; 1104, foam distillation tower foam outlet; 501, gas inlet; 502, liquid inlet; 503, foam outlet; 504, liquid outlet; 505, filler; 506, liquid distributor. DETAILED DESCRIPTION

[0028] The present invention will be further described below by means of specific embodiments, but the protection scope of the invention is not limited thereto. Example 1

[0029] like Figures 1 to 9 As shown, a foam separation device for high-efficiency foaming under ultra-gravity comprises an ultra-gravity rotating packed bed 5, a foam distillation tower 6 and a foam stripping tower 11; the foam distillation tower 6 is connected to the top of the ultra-gravity rotating packed bed 5; the foam stripping tower 11 is connected to the bottom of the ultra-gravity rotating packed bed 5; The bottom of the foam distillation tower 11 and the high gravity rotating packed bed 5 are connected to a gas delivery pipeline, which is composed of a blower 7, a gas buffer tank 8, a gas valve 9, and a gas flow meter 10 connected in sequence. The gas delivery pipeline is connected to the gas inlet 1101 of the foam distillation tower and the gas inlet 501 of the high gravity rotating packed bed; The ultra-gravity rotating packed bed 5 is connected to a liquid delivery pipeline, and the liquid delivery pipeline includes a raw material liquid storage tank 1, a pump 2, a liquid valve 3 and a liquid flow meter 4 which are connected in sequence.

[0030] Furthermore, the ultra-gravity rotating packed bed 5 includes a rotor, a packing 505, a shell, a motor 19, and a liquid distributor 506. A gas inlet 501 (connected to a gas delivery pipeline) is provided on the lower side of the shell, a liquid inlet 502 and a foam outlet 503 are provided on the top, and a liquid outlet 504 is provided on the bottom; various packings 505 are installed in the rotor, and the bottom of the rotor is connected to the motor 19 and is driven to rotate by the motor 19; the foam outlet 503 of the ultra-gravity rotating packed bed 5 is connected to the gas inlet 601 of the foam distillation tower, and its liquid outlet 504 is connected to the foam outlet 1104 of the foam distillation tower; the liquid inlet 502 is connected to the liquid delivery pipeline, and the liquid is transported to the inside of the packing through the liquid distributor 506.

[0031] Furthermore, the foam distillation tower 6 has a cylindrical body and an elbow at the top, the elbow is semicircular, and the other end of the elbow is connected to an overflow hood 13, wherein the ratio of the bottom diameter to the upper diameter of the overflow hood is 1:1~10:1, and the overflow hood is straight or gradually expanding, and its shape is determined by the diameter ratio; the overflow hood 13 is connected to a foam catcher 15; a reflux pipe is arranged below one side of the foam distillation tower 6, and a part of the reflux liquid in the foam catcher 15 flows into the foam distillation tower 6, and the other part enters the defoaming liquid collecting tank 17; a diverter valve 16 is provided on the liquid outlet pipe of the foam catcher 15, and the diverter valve 16 can be adjusted manually or automatically, and the diversion ratio of the reflux liquid and the defoaming liquid is controlled by adjusting the opening of the valve, and a flow meter is installed on each of the pipes for the reflux liquid to enter the foam distillation tower 6 and the defoaming liquid to enter the collecting tank, so as to monitor the flow of the reflux liquid and the defoaming liquid in real time, accurately adjust the opening of the valve, and realize dynamic control of the liquid flow. If conditions permit, an automatic control system can be installed to automatically adjust the opening of the diverter valve according to the preset diverter ratio. For example, when the liquid reaches a certain reflux volume, the system automatically reduces the reflux volume and increases the amount of defoaming liquid.

[0032] Furthermore, the structure of the overflow prevention cover 13 is: a bowl-shaped structure with upper and lower openings, the upper opening is connected to an elbow, and the lower opening is connected to a foam catcher to prevent foam from overflowing and affecting the separation efficiency; the structure of the foam catcher is: the body of the device is cylindrical, and an ultrasonic rod 14 is installed on one side of the interior, and the ultrasonic rod extends into the interior to break the foam; the ultrasonic rod 14 is connected to an ultrasonic disperser 18; a needle-shaped foam breaker is arranged at the bottom and side of the foam catcher, and the needle-shaped foam breaker is a mace-shaped structure with sharp thorns arranged upward; the ultrasonic rod and the needle-shaped foam breaker can be used simultaneously or separately, and the size of the needle-shaped foam breaker is determined according to the size of the foam catcher.

[0033] Furthermore, the foam distillation tower 11 has a cylindrical body, the top foam outlet is connected to the liquid outlet of the supergravity rotating packed bed, the gas blown out by the fan enters the tower from the gas inlet, and a gas distributor 1102 is provided above the gas inlet; the residual liquid outlet is provided on the side of the bottom of the tower and is connected to the residual liquid collection tank 12.

[0034] Furthermore, the residual liquid collecting tank 12 is connected to the liquid inlet of the high gravity rotating packed bed 5 .

[0035] Furthermore, the packing 505 of the high gravity rotating packing bed is at least one or more combinations of ball ring packing, wire mesh packing, spherical packing, and arc saddle packing, and the type of packing can be replaced.

[0036] Furthermore, the height-to-diameter ratio of the foam distillation tower 6 and the foam stripping tower 11 is in the range of 5-50.

[0037] The present invention provides a foam separation method of supergravity high-efficiency foaming. In the above-mentioned foam separation device of supergravity high-efficiency foaming, a raw material liquid is foamed by a supergravity rotating packed bed to generate a foam phase and a liquid phase. The foam phase enters a foam distillation tower through a gas outlet of the rotating packed bed, and a high-concentration target substance is collected at the top of the foam distillation tower; the liquid phase enters a foam stripping tower due to gravity for further foam separation, and the remaining liquid phase component is obtained at the bottom of the foam stripping tower.

[0038] The above-mentioned high-efficiency foaming foam separation method comprises the following steps: The raw material liquid is placed in the raw material liquid storage tank 1, and the supergravity rotating packed bed is preheated first, a certain speed is set, and the motor 19 is started. The liquid in the raw material liquid storage tank is pumped into the supergravity rotating packed bed through the liquid delivery pipe from the liquid inlet 502, and is sprayed radially through the inner edge of the packing 505 by the liquid distributor 506. At the same time, the fan 7 is started to blow in gas, and the gas is passed through the gas buffer tank 8. The gas flow meter 10 is adjusted to make the intake speed blow in at a specified flow value. When the gas speed tends to be stable, the gas is divided into two paths and enters the foam distillation tower 11 and the supergravity rotating packed bed 5 respectively. One gas pipeline enters from the gas inlet 1101 of the foam distillation tower through the gas distributor 1102 and rises to the supergravity rotating packed bed 5. The other gas pipeline enters the supergravity rotating packed bed 5 from the gas inlet 501. Then the two gases are collected in the rotating packed bed 5. Driven by the motor, the rotor and the filler rotate at a high speed together, fully contacting with the gas, increasing the gas-liquid mass transfer contact area, rapidly generating bubbles, and starting the foam separation process; the raw liquid and the gas are fully contacted in the rotating filler bed, generating a large number of evenly distributed submillimeter microbubbles, and under the action of centrifugal force, the bubbles are thrown between the outer edge of the filler and the inner wall of the shell, and due to the action of gas pressure, the bubbles enter the foam distillation tower 6 from the foam outlet 503 to realize the foam separation process, and the foam enters the foam catcher 15 through the overflow prevention cover 13, and most of the bubbles form defoaming liquid in the foam catcher. The split ratio of reflux liquid and defoaming liquid is controlled by adjusting the opening of the diverter valve 16 on the liquid outlet pipe of the foam catcher, wherein a part of the defoaming liquid enters the defoaming liquid collecting tank 17, and the other part of the defoaming liquid is introduced into the foam distillation tower 6 from the side port 602 of the foam distillation tower as reflux liquid; at the same time, the foam interstitial liquid and the reflux liquid flow into the supergravity rotating packed bed 5 due to gravity during the foam separation process and are discharged through the liquid outlet 504, and transferred to the foam distillation tower 11, and the continuously rising gas and liquid are separated from the foam again, and the foam is transferred to the supergravity rotating packed bed again under the action of the gas, and finally returns to the foam catcher 15, until the foam no longer overflows, the valve 16 of the reflux pipe is closed, and the remaining defoaming liquid is all transferred to the defoaming liquid collecting tank 17, and the residual liquid in the foam distillation tower 11 is introduced into the residual liquid collecting tank 12, and the residual liquid is finally collected. After use, it is necessary to add deionized water to clean the foam tower and the supergravity rotating packed bed more than twice.

[0039] In the above method, the gas-liquid contact mode is one of cross-flow, counter-flow or parallel flow, the hypergravity factor is 5-120; the gas is at least one or more of air, carbon dioxide, nitrogen, oxygen or inert gas.

[0040] The separation efficiency of foam separation technology is evaluated by the enrichment ratio E and the recovery rate R: Recovery rate:

[0041] Enrichment ratio:

[0042] In the formula, C f Indicates the concentration of target substance in the collected defoaming solution (mg / L), C 0 represents the initial concentration of the target solute in the feed solution (mg / L), C w Indicates the concentration of target substance in the residual liquid (mg / L); V w represents the residual liquid volume (L), V 0 represents the volume of the raw material solution (L), V f Indicates the volume of defoaming solution (L).

[0043] In order to make the above-mentioned purpose of the present invention more intuitive, the specific implementation methods of the technical solution of the present invention are described in detail below in conjunction with specific embodiments.

[0044] Example 2: The experiment uses a simulated surfactant wastewater sodium dodecylbenzene sulfonate (SDBS) aqueous solution as the system, the SDBS concentration is 300 mg / L, the experiment is a continuous operation, and the wastewater treatment volume is 4 L each time; the surfactant wastewater is pumped in through the liquid inlet 502 of the supergravity rotating packed bed, the liquid phase height is 500 mm, the foam height is 800 mm, the gas velocity is 300L / h, the feed flow rate is 300mL / min, the supergravity factor is 40, the experimental temperature is maintained at 25°C, the operation time is 40 min, and the experiment is stopped when the foam no longer bulges, the foam enters the defoaming liquid collection tank 17, and the remaining liquid enters the remaining liquid collection tank 12 for collection. Finally, the recovery rate of SDBS in this embodiment is 98.79%, the enrichment ratio is 35.79, and the separation effect is good. Example 3

[0045] In this experiment, simulated soybean whey wastewater was used as the separation system to extract soybean whey protein from the wastewater. Based on the study of the effects of initial pH value, bubble size, apparent gas velocity, feed concentration and foam layer height on the foam separation of soybean protein wastewater, a supergravity high-efficiency foaming foam separation device that can simultaneously improve the enrichment ratio and recovery rate was invented. With SDS as the capture agent and foaming agent, the optimal separation conditions were determined. The experimental temperature was maintained at 25°C, the whey protein concentration was 200 mg / L, the pH was 4.1, the supergravity factor was 30, the gas velocity was 40 L / h, the feed flow rate was 350 mL / min, the foam phase was 500 mm, and the liquid phase height was 700 mm. The operation time was 35 min. After the residual liquid entered the residual liquid tank, it was mixed with the raw material liquid for foam separation again. The experiment was stopped when the foam no longer bulged. The foam entered the defoaming liquid collection tank 17, and the residual liquid entered the residual liquid collection tank 12 for collection. Finally, the total recovery rate of soy whey protein in this embodiment was 98.8%, the enrichment ratio was 40.1, and the separation effect was good.

[0046] For matters not covered in the embodiments of the present invention, those skilled in the art can select from the prior art.

[0047] The above disclosure is only a specific implementation of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art can easily conceive of changes or substitutions within the technical scope disclosed in the present invention, which should all be included in the protection scope of the present invention.

Claims

1. A super gravity high efficiency foaming foam separation device, characterized in that: It includes a supergravity rotating packed bed, a foam distillation tower and a foam stripping tower; the foam distillation tower is connected to the top of the supergravity rotating packed bed; the foam stripping tower is connected to the bottom of the supergravity rotating packed bed; the bottom of the foam stripping tower and the supergravity rotating packed bed are connected to a gas delivery pipeline, the gas delivery pipeline consists of a blower, a gas buffer tank, a gas valve, and a gas flow meter connected in sequence, and the gas delivery pipeline is connected to the gas inlet of the foam stripping tower and the supergravity rotating packed bed; the supergravity rotating packed bed is connected to a liquid delivery pipeline, and the liquid delivery pipeline includes a raw material liquid tank, a pump, a liquid valve and a liquid flow meter connected in sequence.

2. The ultra-gravity high-efficiency foaming foam separation device according to claim 1 is characterized in that: The ultra-gravity rotating packed bed comprises a rotor, a packing, a shell, a motor, and a liquid distributor. A gas inlet is arranged on the lower side of the shell, a liquid inlet and a foam outlet are arranged on the top, and a liquid outlet is arranged on the bottom. Various packings are installed in the rotor, and the bottom of the rotor is connected to the motor and driven to rotate by the motor. The foam outlet of the ultra-gravity rotating packed bed is connected to the gas inlet of the foam distillation tower, and the liquid outlet is connected to the foam outlet of the foam distillation tower. The liquid inlet is connected to a liquid delivery pipeline, and the liquid is delivered to the inside of the packing through the liquid distributor.

3. The ultra-gravity high-efficiency foaming foam separation device according to claim 1 is characterized in that: The foam distillation tower body is cylindrical, with an elbow at the top, the elbow is semicircular, and the other end of the elbow is connected to an anti-overflow hood, wherein the ratio of the bottom diameter to the upper diameter of the anti-overflow hood is 1:1~10:1, and the anti-overflow hood is straight or gradually expanding, and its shape is determined by the diameter ratio; the anti-overflow hood is connected to a foam catcher; a reflux pipe is arranged below one side of the foam distillation tower, and a part of the reflux liquid in the foam catcher flows into the foam distillation tower again, and the other part flows into a defoaming liquid collecting tank; a diverter valve is arranged on the liquid outlet pipe of the foam catcher, and the diverter valve can be adjusted manually or automatically, and the diversion ratio of the reflux liquid and the defoaming liquid is controlled by adjusting the opening of the valve.

4. The ultra-gravity high-efficiency foaming foam separation device according to claim 1 is characterized in that: The structure of the overflow prevention cover is: a bowl-shaped structure with upper and lower openings, the upper opening is connected to an elbow, and the lower opening is connected to a foam catcher to prevent foam from overflowing; the structure of the foam catcher is: the body of the device is cylindrical, an ultrasonic device is installed on one side of the interior, and an ultrasonic rod is extended into the interior to break the foam; a needle-shaped foam breaker is arranged at the bottom and the side, and the needle-shaped foam breaker is a mace-shaped structure with sharp thorns arranged upward; the ultrasonic rod and the needle-shaped foam breaker can be used simultaneously or separately, and the size of the needle-shaped foam breaker is determined according to the size of the foam catcher.

5. The ultra-gravity high-efficiency foaming foam separation device according to claim 1 is characterized in that: The foam distillation tower body is cylindrical, the top foam outlet is connected to the liquid outlet of the supergravity rotating packed bed, the gas blown out by the fan enters the tower from the gas inlet, and a gas distributor is arranged above the gas inlet; the residual liquid outlet is arranged on the side of the bottom of the tower and connected to the residual liquid collection tank.

6. The ultra-gravity high-efficiency foaming foam separation device according to claim 1 is characterized in that: The packing of the ultra-gravity rotating packing bed is at least one or more combinations of ball ring packing, wire mesh packing, spherical packing, and arc saddle packing, and the type of packing can be replaced.

7. The ultra-gravity high-efficiency foaming foam separation device according to claim 1 is characterized in that: The height-to-diameter ratio of the foam distillation tower and the foam stripping tower ranges from 5 to 50.

8. A method for separating foam by high-efficiency foaming under high gravity, using the foam separation device by high-efficiency foaming under high gravity according to any one of claims 1 to 7, characterized in that: In the ultra-gravity high-efficiency foaming foam separation device, the raw material liquid is foamed by the ultra-gravity rotating packed bed to generate a foam phase and a liquid phase. The foam phase enters the foam distillation tower through the gas outlet of the rotating packed bed, and the high-concentration target substance is collected at the top of the foam distillation tower; The liquid phase enters the foam distillation tower due to gravity for further foam separation, and the remaining liquid phase components are obtained at the bottom of the foam distillation tower.

9. The foam separation method of high-efficiency supergravity foaming according to claim 8, characterized in that The following steps are involved: (1) The raw material liquid is placed in a raw material liquid storage tank, and the supergravity rotating packed bed is started. The liquid in the raw material liquid storage tank is pumped into the supergravity rotating packed bed from the liquid inlet through the liquid delivery pipe, and is sprayed radially through the inner edge of the packing by the liquid distributor. At the same time, the fan is started to blow in gas, which passes through the gas buffer tank and adjusts the gas flow meter. When the gas velocity tends to be stable, the gas is divided into two paths and enters the foam distillation tower and the supergravity rotating packed bed respectively. One gas pipeline enters the foam distillation tower from the gas inlet through the gas distributor and rises to the rotating packed bed. The other gas pipeline enters the supergravity rotating packed bed from the gas inlet. Then the two gas streams are collected in the rotating packed bed; (2) The raw material liquid and the gas are fully contacted in the rotating packed bed, generating a large number of evenly distributed submillimeter microbubbles. Under the action of centrifugal force, the bubbles are thrown between the outer edge of the packing and the inner wall of the shell. Due to the effect of gas pressure, the bubbles enter the foam distillation tower from the foam outlet to realize the foam separation process. The foam enters the foam catcher through the overflow cover. Most of the bubbles form defoaming liquid in the foam catcher through the ultrasonic rod or needle-shaped bubble breaker. The diversion ratio of the reflux liquid and the defoaming liquid is controlled by adjusting the opening of the diversion valve on the outlet pipe of the foam catcher. Among them, a part of the defoaming liquid enters the defoaming liquid collection tank, and the other part of the defoaming liquid is introduced into the foam distillation tower from the side port of the foam distillation tower as the reflux liquid. (3) During the foam separation process, the foam interstitial liquid and reflux liquid flow into the supergravity rotating packed bed due to gravity and are discharged through the liquid outlet and transferred to the foam distillation tower. The continuously rising gas and liquid realize foam separation again. The foam is transferred into the supergravity rotating packed bed again under the action of the gas and finally returns to the foam catcher. When the foam no longer overflows, the valve of the reflux pipe is closed and the remaining defoaming liquid is transferred to the defoaming liquid collection tank. The residual liquid in the foam distillation tower is introduced into the residual liquid collection tank and the residual liquid is finally collected.

10. The foam separation method of high-efficiency supergravity foaming according to claim 9, characterized in that: The gas-liquid contact mode is one of cross-flow, counter-flow or parallel flow, and the hypergravity factor is 5-120; the gas is at least one or more of air, carbon dioxide, nitrogen, oxygen or inert gas.

Images