1. TECHNICAL FIELD OF THE INVENTION

The present disclosure generally relates to a system and method of an ultrasonic agitator, comprising at least one ultrasonic transducer with or without an arrangement of packed bed assembly for gas and water separation process; specifically to increase mass transfer rate or reaction rate between at least one fluid for absorption, desorption, and distillation system.

2. BACKGROUND OF THE INVENTION Sweet natural gas fields are depleting worldwide. Southeast Asia is one of the regions that possesses the highest numbers of acid gas fields. In order to tap these natural gas resources, acid gases (for example CO2) and water in these sour gas reservoirs must be removed at offshore prior to the delivery to the end-user. Absorption is one of the best separation technologies used for natural gas purification. It consistently provides better separation performance with minimum hydrocarbon losses. The concept of using ultrasonic agitator to enhance the absorption process has been proven in lab scale experiment. However, there is no scale-up history of this technology for industry application. Based on the above motivation, a multilayer ultrasonic agitation system has been developed for the scale-up purpose for the acid gas absorption process with minimum footprint and tonnage. The mass transfer of two-phase system is encountered in absorption, desorption, and distillation processes. These processes are commonly used for gas separation application. Therefore, the intensification technology attaches commercial interest to enhance the absorption process. Several designs and methods have been developed for promoting the two- phase mass transfer process for gas separation, such as packed bed columns, rotating packed bed, membrane contactor, microchannel and ultrasonic agitator. Nonetheless, some drawbacks are found in the current absorption technologies.

For example, the conventional packed bed absorption technology is limited by the low mass transfer coefficient result in its larger footprint. The identified major problem of packed bed column is the enormous column required to achieve the targeted performance.

Therefore, the advanced technology is essential in order to increase the flexibility of two-phase mass transfer process. Ultrasonic agitator emerges as a potential intensification technology for two-phase mass transfer process. The ultrasonic agitator provides the physical effect in term of lower mass transfer resistance of liquid phase via the ultrasonic vibration and fountain formation. In addition, ultrasonic agitator is also plausible to induce the sonochemical effect for chemical reaction intensification via the micro -turbulent and cavitation effect. The ultrasonic piezo material is less than 2 mm thickness for high frequency vibration. Therefore, the ultrasonic transducer can be attached on the absorption tray with introduction of the packed bed assembly to further improve the two- phase mass transfer process. Ultrasonic packed bed agitator also offers a series of the advantages over the other two-phase mass transfer system, which includes the high flexibility of the solvent, operating condition, high performance stability. Due to the resonant vibration of packed bed assembly, the ultrasonic packed bed is resistance of suspended particle.

Nevertheless, the design of the prior art is limited by their low flow capacity, which is not able to fulfill the industry application. This invention provides a scale-up solution to treat the high flow capacity for the industry process using ultrasonic agitator. The absorption column is designed in such a way to integrate the multiple ultrasonic transducer on the tray.

3. SUMMARY OF THE INVENTION

The present disclosure concerns a gas-liquid mass transfer system, which comprising at least one packed bed assembly within at least one ultrasonic transducer, for varied gas-liquid mass transfer application, such as absorption, desorption, and distillation. The configuration of the system can be designed in a single layer/ segment or multiple layers/ segments.

The frequency of ultrasound produced from the ultrasonic transducer is more than 1 MHz to generate the fountain formation.

The packed bed assembly is designed to allow the fountain formation occur within the packed bed without any distortion of fountain. The packed bed assembly can be designed to match with ultrasonic resonant frequency to amplify the vibration.

The packed bed assembly is designed in such a way to better circulation of the liquid phase. According to the preferred embodiment of the present disclosure the following is provided:

An ultrasonic agitator for two-phase fluids mass transfer, comprising: a chamber; and characterized in that the two-phase fluids are a first fluid and a second fluid; the chamber comprising: first inlet to inject an untreated first fluid and first outlet to expel treated first fluid; second inlet to inject lean second fluid and second outlet to expel rich second fluid; the lean second fluid absorbed at least one group of targeted gas in the untreated first fluid, thereby resulted the treated first fluid and rich second fluid; at least one segment therein, wherein each segment comprising a first tray; the first or sonication tray submerged in the second fluid of a predetermined height, comprising at least one ultrasonic transducer electrically coupled to a generator configured to emit a predetermined resonant frequency, thereby produce second fluid fountain formation upwardly. According to the preferred embodiment of the present disclosure the following aspect is provided:

A method of ultrasonic agitator for two-phase fluids mass transfer, comprising steps of: injecting untreated hydrocarbon gas, natural gas, sour gas, or flue gas into a chamber comprising transducer which energizing at a predetermined resonant frequency; injecting fresh solvent or lean solvent from a desorption system into ultrasonic agitator; energizing ultrasonic transducer to produce ultrasonic streaming force to capture targeted gas from the untreated gas; ejecting treated gas from the ultrasonic agitator; and ejecting rich solvent from the ultrasonic agitator; characterized in that vibrating the ultrasonic agitator at the predetermined resonant frequency. 4. BRIEF DESCRIPTION OF THE DRAWINGS Other aspect of the present disclosure and their advantages will be discerned after studying the Detailed Description in conjunction with the accompanying drawings in which:

FIG. 1 illustrates an internal view of a preferred embodiment of the present disclosure.

FIG. 2(i) illustrates an enlarged internal view of a preferred embodiment first or sonication tray in Segment 1.

FIG. 2(ii) illustrates an enlarged internal view of a preferred embodiment second tray in Segment 2. FIG. 3 illustrates an internal view of another embodiment of the present disclosure.

FIG. 4(i) illustrates an enlarged internal view of another embodiment first or sonication tray in Segment 1.

FIG. 4(ii) illustrates an enlarged internal view of another embodiment second tray in Segment 1.

FIG. 5 illustrates an internal view of another embodiment of the present disclosure.

FIG. 6(i) illustrates an enlarged internal view of the first or sonication tray in Segment 1, similar to FIG. 4(i). FIG. 6(ii) illustrates an enlarged internal view of another embodiment of first or sonication tray in Segment 2, here illustrates a packed bed assembly is mechanically coupled to the tray.

FIG. 6(iii) illustrates an enlarged internal view of another embodiment second tray in Segment 2, here illustrates a packed bed assembly is mechanically coupled to the tray.

FIGS. 7(a) (b) (c) illustrate cross flow, counter-current flow, or zigzag flow of gas flow paths and solvent flow paths, respectively, which can be configured in the present disclosure. FIG. 8A illustrates a side view of one of the segments/ layers of the ultrasonic agitator with packed bed assembly and ultrasonic transducers.

FIG. 8B illustrates a side view of the segment ultrasonic agitator being energized to produce fountain formations.

FIG. 9A illustrates an exemplary top view of an arrangement of packed bed assembly over an arrangement of ultrasonic transducers.

FIG. 9B illustrates partial top view of FIG. 9A.

FIG. 10 illustrates an exemplary process flow of the present disclosure.

TABLE 1 lists type of targeted gases that contained in the natural gas, flue gas, sour gas, or the like, that can be removed by its corresponding solvents. 5. DETAILED DESCRIPTION OF THE DRAWINGS

In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the disclosure. However, it will be understood by the person having ordinary skill in the art that the disclosure may be practised without these specific details. In other instances, well known methods, procedures and/or components have not been described in detail so as not to obscure the disclosure.

The disclosure will be more clearly understood from the following description of the embodiments thereof, given by way of example only with reference to the accompanying drawings, which are not drawn to scale.

As used in this disclosure and the appended claims herein, the singular forms "a", "an", and "the" include plural referents unless the context clearly dictates or denotes otherwise. Ranges may be expressed herein as form "about" one particular value, and/ or to "about" another particular value. When such a range is expressed, another embodiment includes from the one particular value and/or to the other particular value. Similarly, when values are expressed as approximations, by use of the antecedent "about," it will be understood that the particular value forms another embodiment. It will be further understood that the endpoints of each of the ranges are significant both in relation to the other endpoint, and independently of the other endpoint.

Referring to FIG. 1, there is shown an internal view of a preferred embodiment of the present disclosure, an ultrasonic agitator (1) for gas separation. Here shown a column (10), reactor, sonication chamber, chamber or the like, that comprising at least one segment demarcated as "Segment 1" on ground level, 2, and so forth.

Accordingly in this embodiment, the column, reactor, or chamber (10) can be designed to withstand pressurized or high temperature fluids therein. In this disclosure, fluids are defined as gas (first fluid) and solvent (second fluid).

A two-phase fluid is defined as chemical/ mechanical property changes due to mass transfer of the fluid itself or between the fluids, for example, under sonication energy of a predetermined resonant frequency emitted by ultrasonic transducer, the solvent (second fluid) volume will bulge and fountain formation can be created. The top portion of the fountain formation, being the furthest portion from the solvent level, may break into droplet, mist, vapor, or the like. Hence, a mass transfer or absorption of the fluids, specifically the solvent absorbs at least one group of targeted gas in the gas can be realized. Referring to FIG. 2(i), there is shown an enlarged internal view of a preferred embodiment first tray or sonication tray (21) in Segment 1. Accordingly, a first inlet (2) is provided at the bottommost of the chamber, to inject untreated first fluid or natural gas, flue gas, sour gas, or the like. A distributor (9) substantially a tray, comprising a plurality of apertures, tubes, or channels enabling a uniform distribution of the untreated gas. Each segment of the chamber can be configured to have only a first tray (21) as in Segment 1, or may have a first tray (21) and a second tray (25) as in Segment 2. Referring to FIG. 2(i), the untreated first fluid enters the Segment 1 through gas holes or apertures (14) of the first or sonication tray (21). The first or sonication tray comprising at least one ultrasonic transducer (11); the transducers are being submerged in the second fluid (5). Referring FIG. 2(ii) there is shown an enlarged internal view of preferred embodiment second tray (25) in the Segment 2, the tray (25) is comprising a plurality of first fluid apertures (18) and second fluid apertures (15) allowing them to flow therethrough.

Referring to FIG. 3, there is shown an internal view of another embodiment of the present disclosure, an ultrasonic agitator (1) for gas separation. Here shown the column, reactor, sonication chamber, chamber or the like, that comprising at least one segment demarcated as "Segment 1" on ground level, 2, 3, and so forth.

Accordingly, a first inlet (2) is provided at the bottommost of the chamber, to inject untreated first fluid or natural gas, flue gas, sour gas, or the like. A distributor (9) substantially a tray, comprising a plurality of apertures, tubes, or channels enabling a uniform distribution of the untreated gas. Each segment of the chamber is confined or defined between a first tray (21) and second tray (25). Referring to FIG. 4(i), the untreated first fluid enters the Segment 1 through gas holes or apertures (14) of the first or sonication tray (21). The first or sonication tray comprising at least one ultrasonic transducer (11); the transducers are being submerged in the second fluid (5). Referring FIG. 4(ii) there is shown an enlarged internal view of another embodiment second tray (25) in the Segment 1, the tray (25) is comprising a plurality of first fluid apertures (18) and second fluid apertures (15) allowing them to flow therethrough. Referring to FIG. 3, specifically between Segment 1-2 and Segment 2-3 illustrates that the first tray (21) and the second tray (25) are separated trays. It is understood that a person skilled in the art can combine, modify, or alter the trays (21)(25) into an integral tray comprising features of the first tray's sonication and the second tray's with a plurality of apertures enabling the two- phase fluids therethrough. As such, this embodiment of integral tray can co share in more than one segment.

Referring again to FIG. 3, the second fluid inlet (3) supplies unsaturated solvent for Segment 3, firstly the solvent passes through solvent inlet distributor (15) of the second tray (25), then accumulated in the first tray (21) to be subject a predetermined resonant frequency from the ultrasonic transducer (11). The spent or saturated second fluid is then discharged through the second fluid outlet (13). Accordingly, each segment is provided at least one second fluid inlet and outlet. The second fluid remains in the same segment and does not flow to the different segments. Accordingly in this embodiment shown a cross flow configuration allows the first fluid to subject at least one segment of absorption, then a filter (8) is disposed at the uppermost part of the chamber, the first fluid is filtered prior expel through the first outlet (6).

Accordingly, the cross flow configuration enables each segment of the chamber with at least one second fluid inlets (3) to feed in lean second fluid, then second fluid outlets (13) to discharge rich second fluid therefrom. Accordingly, the rich second fluid can be channelled to a desorption system whereby the targeted gas such as carbon dioxide can be separated so that the second fluid becomes lean, thereby it can be recirculated back to the ultrasonic agitator (1). Referring to FIG. 5, there is shown an internal view of another embodiment of the present disclosure. Again, it is understood that a person skilled in the art can combine, modify, or alter the trays (21)(25) into an integral tray, whereby the first tray (21) has sonication and packed bed assembly (22); whereby the second tray (25) with a plurality of apertures enabling the two- phase fluids therethrough and packed bed assembly (22). As such, this embodiment of the integral tray can co-share in more than one segment.

Referring to FIG. 6(i), there is shown an enlarged internal view of the first or sonication tray (21) used in Segment 1, similar to FIG. 4(i). A plurality of gas holes (14) is provided to allow gas flow. In this case, the gas flows from beneath of the tray to the solvent (5). Then referring to FIG. 6(ii), there is shown an enlarged internal view of another embodiment of first or sonication tray (21) used in Segment 2. Accordingly, a packed bed assembly (22) is mechanically coupled to the first tray (21). Accordingly, the gas flows upwardly from a lower segment or Segment 1 through gas holes (14) of the tray (21) to the solvent (5).

Then referring to FIG. 6(iii), there is shown an enlarged internal view of another embodiment second tray (25) used in Segment 2. Accordingly, a packed bed assembly is mechanically coupled to the second tray (25). Accordingly, the gas flows upwardly from a lower segment or Segment 1 through gas holes (18) of the second tray (25). The second tray (25) further comprising a solvent inlet distributor (15) to distribute solvent to lower segment.

Referring to FIGS. 7(a) (b) (c) illustrate cross flow, counter -current flow, or zigzag flow, respectively, of how gas flow and solvent flow paths can be configured in the present disclosure. In the cross flow configuration (also shown in FIG. 3), gas inlet is provided at the bottommost of the chamber to inject untreated gas, the gas may pass through an inlet gas distributor, then the gas is being treated in each segment of the chamber upwardly by passing through gas hole. Finally, the treated gas is filtered and discharged through the topmost of the chamber. Solvent inlet is provided at each segment to inject fresh solvent therein and remained therein to be subject sonication energy, depleted/ rich solvent is ejected out from the segment. In the counter-current configuration (also shown in FIG. 5), gas inlet is provided at the bottommost of the chamber to inject untreated gas, the gas may pass through an inlet gas distributor, then the gas is being treated in each segment of the chamber upwardly by passing through gas hole. Finally, the treated gas is filtered and discharged through the topmost of the chamber. Solvent inlet is provided at the topmost of the chamber, the fresh or lean solvent is subject to sonication energy therein to enable mass transfer or absorption with the gas, the solvent can pass through each segment downwardly through configured solvent channels, distributors, or apertures. Then depleted/ rich solvent is collected in a solvent sump at the bottommost of the chamber then ejected out from the chamber.

Accordingly, in a zigzag flow configuration, edges or rims of the first tray and second tray can be configured to have baffles, channels, ducts, apertures or the like, to allow an upwardly gas flow and downwardly solvent flow paths. Both fluids are required to flow entire horizontal plane of corresponding segment prior flowing to different segments.

Referring to FIG. 8A, there is shown a side view of one of the segments of the ultrasonic agitator with packed bed assembly and ultrasonic transducers (11). Accordingly in this embodiment, the segment is defined or confined between a first tray (21) and second tray (25), wherein the second tray is disposed above the first tray. The first tray (21) or sonication tray comprising a plurality of ultrasonic transducer (11) arranged in such a way sonication energy is directed upwardly. The first tray also comprising a plurality of gas hole (14) which enable gas flow from segment beneath. Accordingly, the second tray (25) comprising at least one solvent inlet distributor (15) that enables solvent flow from upper segments, also comprising a plurality of gas holes (18) that enables gas flow upwardly to upper segments.

Referring to FIG. 8B, there is shown a side view of one of the segment of the ultrasonic agitator being energized to produce fountain formations (27). As the solvent flows down from the second tray (25) through solvent inlet distributor, the solvent (5) accumulated at a predetermined level (5h) on the first or sonication tray (21), preferably the level is higher than the ultrasonic transducers (11) and nozzle (12). The transducers are electrically coupled (shown in parallel connection) to a signal/ function generator and amplifier (30), as the transducers emit a predetermined resonant frequency upwardly will cause solvent to bulge upward to form fountain formations. Top region of the fountain formations may contain solvent droplets/mists/ vapors (28) so that a mass transfer, absorption can be enabled on the untreated gas (26) inside the segment. The untreated gas may get partially or fully treated by having at least one group of targeted gas (for example carbon dioxide) absorbed by the solvent. The partially or fully treated gas can flow upwardly though the second tray (25) to enter into upper segments.

Accordingly, the packed bed assembly is arranged within the ultrasonic agitator without distorting ultrasonic fountain formation. The packed bed assembly can be fine-tuned to match with ultrasonic frequency to induce the resonant vibration. The ultrasonic agitator with the packed bed assembly offers a better circulation and mixing effect for promoting the mass transfer process, which is potentially used for absorption, desorption, and distillation system.

Referring to FIG. 9 A, there is shown an exemplary top view of an arrangement of packed bed assembly over an arrangement of ultrasonic transducers. FIG. 9B illustrates partial top view of FIG. 9A demarcated by a box.

Accordingly, the packed bed assembly is arranged in such a way that the ultrasonic transducer (11) is surrounded therein, when the transducer (11) produced sonication energy at a predetermined resonant frequency, for example, more than 1 MHz, will cause a fountain formation upwardly but inside the arrangement of packed bed assembly. The sonication energy also vibrates the packed bed assembly. Furthermore, the transducer (11) can be coupled with a nozzle (12).

Two-phase fluids are defined as a first fluid and a second fluid. The first fluid is hydrocarbon gas, sour gas, flue gas, or a combination thereof. An example of the hydrocarbon gas is natural gas. The second fluid is liquid solvent wherein the solvent can be physical or chemical solvent type to absorb at least one group of targeted gas contain in the first fluid. An example of the targeted gas is carbon dioxide. Accordingly, an ultrasonic agitator (1) comprising: a chamber (10) comprising: a first inlet (2) to inject an untreated first fluid and first outlet (6) to expel treated first fluid, second inlet (3) to inject lean second fluid and second outlet (13) to expel rich second fluid; the lean second fluid absorbed at least one group of targeted gas in the untreated first fluid, thereby resulted the treated first fluid and rich second fluid. The chamber comprising at least one segment therein, wherein each segment is defined between a first tray (21) and second tray (25). The second tray disposed above the first tray, comprising a plurality of apertures (18) enabling the two-phase fluids therethrough. The first tray (21) and second tray (25) are configured with channels or baffles to enable cross flow, counter-current flow, or zigzag flow of the first fluid and second fluid in the chamber (10).

Accordingly, the chamber (10) comprising filter (8) therein to filter the first fluid prior expelling through the first outlet (6). Furthermore, the chamber (10) comprising at least one distributor tray (9) therein, containing apertures, channels, or tubes to enable uniform flow of the first fluid. The segment comprising: a packed bed assembly arranged around the ultrasonic transducer such that the fountain formation is generated therein.

The packed bed assembly is designed to allow the fountain formation occur within the packed bed without any distortion of fountain. Optionally, the thickness of the packed bed assembly can be designed to match with the ultrasonic resonant frequency to allow the vibration of the packed bed. Accordingly, the segment may comprise at least one inlet (3) and outlet (13) for the second fluid.

Accordingly, the first or sonication tray submerged in the second fluid of a predetermined height, comprising at least one ultrasonic transducer (11) electrically coupled to a generator (30) configured to emit a predetermined resonant frequency of more than 1 MHz, thereby produce second fluid fountain formation (27) upwardly. The generator (30) comprising a signal generator, function generator, and amplifier.

Referring to FIG. 10, there is shown an exemplary process flow of the present disclosure. A method of ultrasonic agitator (20) for two-phase fluids mass transfer, comprising steps of: injecting, untreated hydrocarbon gas, natural gas, sour gas, or flue gas into a chamber comprising transducer which energizing at a predetermined resonant frequency (201); injecting, fresh solvent, or recycled solvent from a desorption system into ultrasonic agitator (202); energizing, the ultrasonic transducer to produce ultrasonic streaming force to capture the targeted gas from the untreated gas (203); ejecting, treated gas from the ultrasonic agitator (204); and ejecting, rich solvent from the ultrasonic agitator (205). The ultrasonic agitator vibrates at the predetermined resonant frequency of more than 1 MHz. Referring to TABLE 1, there is shown type of targeted gases that contained in the natural gas, flue gas, sour gas, or the like, that can be removed by its corresponding solvents. The mass transfer and absorption between the fluids is enabled, so that at least one group of the targeted gases (such as CO ₂ , H ₂ S, NOx, SO ₂ , NH ₃ , H ₂ O, HCN) is stripped or removed from the natural gas, flue gas, sour gas, or the like.

Accordingly, CO2 can be removed or absorbed by chemical solvents such as: amine-based solvents, carbonate-based solvents, hydroxide-based solvents, chilled ammonia, amino-acid salts, glycerol-based solvents, blended solvents, etc.

Accordingly, CO2 can be removed or absorbed by physical solvents such as: dimethyl ether of polyethylene glycol, methanol, n-methyl-2-pyrrolidone, propylene carbonate, water, ionic liquids, etc. Accordingly, H2S can be removed or absorbed by amine-based solvents, carbonate-based solvents, hydroxide-based solvents, methanol, n-methyl-2- pyrrolidone, poly(ethylene glycol) dimethyl ether, sulfolane & diisopropanolamine, ionic liquids, etc.

Accordingly, NOx and SO2 can be removed or absorbed by amine-based solvents, carbonate-based solvents, hydroxide-based solvents, water, etc.

Accordingly, N¾ can be removed or absorbed by water, ionic liquids, etc.

Accordingly, H2O can be removed or absorbed by glycol, hygroscopic salts, etc.

Accordingly, HCN can be removed or absorbed by oxidant solution. While the present disclosure has been shown and described herein in what are considered to be the preferred embodiments thereof, illustrating the results and advantages over the prior art obtained through the present disclosure, and the disclosure is not limited to those specific embodiments. Thus, the forms of the disclosure shown and described herein are to be taken as illustrative only and other embodiments may be selected without departing from the scope of the present disclosure, as set forth in the claims appended hereto.