1. TECHNICAL FIELD OF THE DISCLOSURE

The present disclosure generally relates to an ultrasonic packed bed agitator comprising an assembly for gas separation from a hydrocarbon gas, sour gas, flue gas or the like by mass transfer rate or reaction rate for absorption, desorption, and distillation processes.

2. BACKGROUND OF THE DISCLOSURE

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 resource, acid gases (for example CO2) 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 gas treatment process. For natural gas purification, it consistently provides better separation performance with minimum hydrocarbon losses. Nevertheless, this technology is only feasible for onshore gas processing due to its bulky packed absorption column. For offshore operation, oil and gas (O&G) operators have to rely on cryogenic and membrane technology, which are energy intensive and suffer from high hydrocarbon losses. Based on the above motivation, a compact structured packing system with ultrasonic agitator has been developed to enhance the acid gas absorption process with minimum footprint and tonnage for offshore application. 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 design 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 resonant 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 systems, which includes the high flexibility of the solvent, operating condition, and high performance stability.

This invention provides a better solution to further enhance the absorption process for ultrasonic agitator. The enhancement is contributed by the better circulation of the liquid phase from the ultrasonic fountain. Besides, based on this design, the spent solvent can be discharge efficiently from the reactor.

3. SUMMARY OF THE DISCLOSURE

The present disclosure concerns a gas-liquid mass transfer system, which comprising at least one packed bed assembly configured within at least one ultrasonic transducer, for varied gas-liquid mass transfer application, such as absorption, desorption, and distillation.

Accordingly, the resonant frequency of ultrasound produced from the ultrasonic transducer is more than 1 MHz to generate fountain formation. Accordingly, the packed bed assembly is designed to allow the fountain formation occur within the packed bed without any distortion of fountain.

Accordingly, the packed bed assembly is designed to match with ultrasonic resonant frequency to amplify the vibration.

Accordingly, 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 packed bed agitator (1) for gas separation, characterized in that: said agitator (1) comprising a packed bed assembly (2); and at least one transducer (30) emitting ultrasound energy, the ultrasound energy is configured to energize at resonant frequency to form at least one fountain of a second fluid in a continuous and controlled flow path (F) upwardly of the assembly, then downwardly of the assembly, thereby enabling absorption, surface area, contact time, or mass transfer from a first fluid into the second fluid.

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 exemplary perspective view of an assembly of ultrasonic packed bed assembly.

FIG. 2 illustrates an exemplary perspective view of an outer structure packing. FIG. 3 illustrates an exemplary perspective view of an inner structure packing.

FIG. 4 illustrates an exemplary top view of first layer of the outer structure packing. FIG. 5 illustrates an exemplary top view of first layer of the inner structure packing.

FIG. 6 illustrates an exemplary top view of the outer structure packing of second layer being configured by rotating 22.5° clockwise of center axis from the first layer shown in FIG. 4. FIG. 7 illustrates an exemplary top view of the inner structure packing of second layer being configured by rotating 22.5° clockwise of center axis from the second layer shown in FIG. 5.

FIG. 8A illustrates the outer structure packing from FIG. 6, whereby outer curvilinear surfaces and inner curvilinear surfaces are alternating at a first angle.

FIG. 8B illustrates the inner structure packing from FIG. 7, whereby outer curvilinear surfaces and inner curvilinear surfaces are alternating at a second angle. FIG. 9A shows an exemplary top view of an arrangement of packed bed assembly comprising: first layer of outer structure packing, first layer of inner structure packing, second layer of outer structure packing, second layer inner structure packing, and four units of ultrasonic transducers disposed inside the void.

FIG. 9B shows another exemplary top view of an arrangement of packed bed assembly comprising: first layer of outer structure packing, second layer of outer structure packing, and four units of ultrasonic transducers disposed inside the void. FIG. 9C shows another exemplary top view of an arrangement of packed bed assembly comprising: four units of inner structure packings disposed around an ultrasonic transducer.

FIG. 10 shows a perspective view of a prototype ultrasonic packed bed showing solvent flow path upward from bottom of the bed then spiral downward back to the base (demarcated by arrows).

FIG. 11 shows a top view of the prototype ultrasonic packed bed. The structure packing guides the flow path of the solvent to maximize the absorption performance and solvent absorption capacity. Besides, the spent solvent can be discharged from the ultrasonic agitator efficiently. FIG. 12 illustrates an internal view of prior art ultrasonic agitator disclosed in Malaysian application number PI 2015704436. FIG. 13 illustrates an internal view of the assembly of ultrasonic packed bed can be configured inside the ultrasonic agitator.

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 practiced 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.

In this disclosure, a column, reactor, or chamber can be designed to withstand pressurized or high temperature fluids therein. Accordingly, in this present disclosure, fluids are defined as gas (first fluid) and liquid or solvent (second fluid). TABLE 1 shown a list of targeted gas that contained in the gas (first fluid) such as natural gas, hydrocarbon gas, flue gas, sour gas, or the like, that can be removed by its corresponding 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, when a sonication or ultrasound energy of a predetermined resonant frequency emitted by ultrasonic transducer toward a liquid surface, the liquid or solvent(second fluid) volume will bulge and fountain formation can be created upwardly. The top portion/ region of the fountain formation, being the furthest portion from the liquid level, may break into droplet, mist, vapor, or the like. Hence, a mass transfer or absorption of the fluids, specifically the liquid absorbs at least one group of acidic gas in the gas can be realized.

Referring to FIG. 1, there is shown an exemplary perspective view of an assembly of ultrasonic packed bed assembly (2) specifically for gas separation from a hydrocarbon gas, sour gas, flue gas or the like by mass transfer rate or reaction rate for absorption, desorption, and distillation processes. The packed bed assembly (2), comprising: at least one outer structure packing (10) and at least one inner structure packing (20). For example, the topmost layer of packed bed is formed by an outer structure packing (10a) and an inner structure packing (20a) is disposed inside an inner cavity of the outer structure packing (10a), both are aligned co-radially. Each layer of packed bed can be separated or spaced at a height (h). The assembly (2) is formed by arranging the plurality of outer structure packing (10..10n) and inner structure packing (20..20n) co-axially. Accordingly, total height (TH) of the packed bed assembly (10..10n), from the topmost layer of packed bed (10a) to bottommost layer of packed bed (10h), is lower than the height of the fountain (F) wherein the height of the fountain (F) is defined as the height from the bottommost packed bed layer to the highest point of the second fluid it can stream up, which exceeds the topmost packed bed layer, as shown in FIG. 10.

Referring to FIG. 2, there is shown an exemplary perspective view of an outer structure packing (10). The outer structure packing (10) substantially a disc, comprising a first surface (3) and inner cavity (4).

Referring to FIG. 3, there is shown an exemplary perspective view of an inner structure packing (20). The inner structure packing (20) substantially a disc, comprising a second surface (5) and center cavity (22). Referring to FIG. 4, there is shown an exemplary top view of first layer of the outer structure packing (10a). The first surface (3) is defined by a surface (3a) and a plurality of curvilinear surfaces (3a ¹ ), wherein the curvilinear surfaces (3a ¹ ) extend inwardly therefrom, the surfaces (3a) (3a ¹ ) are configured in such a way that they are alternating at a first angle with respect to center axis of the outer structure packing (10). Accordingly, the inner cavity (4) provides an accommodation for the inner structure packing (20). Referring to FIG. 5, it illustrates an exemplary top view of first layer of the inner structure packing (20a). The inner structure packing of first layer (20a) further comprising orifice, aperture or cavity (21a) disposed on each of the curvilinear surfaces (5a'), this is to allow fluid flow. An orifice, aperture or center cavity (22b) is provided at the center of the inner structure packing so that a spacer, rod, or packing holder (23) with a predetermined height can be inserted therethrough so that each layer of the inner structure packing is distinctively distant apart.

Referring to FIG. 6, it illustrates an exemplary top view of the outer structure packing of second layer (10b) being configured by rotating an angle of 22.5° clockwise of center axis with respect from the outer structure packing of the first layer (10a, FIG. 4).

Referring to FIG. 7, there is shown an exemplary top view of an inner structure packing of second layer (20b) being configured by rotating an angle of 22.5° clockwise of center axis with respect from the inner structure packing of the first layer (20a, FIG. 5). The inner structure packing of second layer (20b) comprising a surface which is defined by a surface (5b) and a plurality of curvilinear surfaces (5b ¹ ), wherein the curvilinear surfaces (5b ¹ ) extend outwardly therefrom, the surfaces (5b) (5b ¹ ) are configured in such a way that they are alternating at a second angle with respect to center axis of the inner structure packing of the first layer (20a).

The inner structure packing of second layer (20b) further comprising orifice, aperture or cavity (21b) disposed on each of the curvilinear surfaces (5b'), this is to allow fluid flow. An orifice, aperture, or center cavity (22b) is provided at the center of the inner structure packing so that a spacer, rod, or packing holder (23) with a predetermined height can be inserted therethrough so that each layer of the inner structure packing is distinctively distant apart. Referring again to FIGS. 6 and 7, in this embodiment, one of the outer curvilinear surface (3b) of the outer structure packing (10b) demarcated by region (B) aligns with one of the outer curvilinear surface (5b') of the inner structure packing (20b) demarcated by region (B').

Referring to FIG. 8A, it illustrates the outer structure packing (10b) taken from FIG. 6, wherein it comprising outer curvilinear surfaces (3b) and inner curvilinear surfaces (3b') which are alternating at a first angle (a). In this embodiment, four outer surfaces and four inner surfaces gives a total of 8 surfaces, being alternating at 22.5° of the first angle.

Referring to FIG. 8B, it illustrates the inner structure packing (20b) taken from FIG. 7, wherein it comprising outer curvilinear surfaces (5b') and inner curvilinear surfaces (5b) which are alternating at a second angle (b). In this embodiment, four outer surfaces and four inner surfaces gives a total of 8 surfaces, being alternating at 22.5° of the second angle.

Referring to FIG. 9 A, there is shown an exemplary top view of an arrangement of packed bed assembly (2) comprising: first layer of outer structure packing (10a), first layer of inner structure packing (20a), second layer of outer structure packing (10b, demarcated by hatch area), and second layer inner structure packing (20b, partially); the packings are arranged such that between the outer structure packing and inner structure packing forms a void (6, gray) enabling at least one ultrasonic fountain formation zone (31, crosshair area) therein. Accordingly, the ultrasonic energy of a single transducer is higher than onset of the fountain formation. Also accordingly, the onset of ultrasonic fountain is depended on the height of the liquid/ solvent layer, which is about 1.5 Watt for 5 cm height of liquid/ solvent layer.

Referring to FIG. 9B, there is shown another exemplary top view of an arrangement of packed bed assembly (2) comprising: first layer of outer structure packing (10a), second layer of outer structure packing (10b, demarcated by hatch area), the packings are arranged such that the outer structure packing forms a void (6, gray) enabling at least one an ultrasonic fountain formation zone (31, crosshair area) therein. Accordingly, the ultrasonic energy of a single transducer is higher than onset of the fountain formation. Also accordingly, wherein the onset of ultrasonic fountain is depended on the height of the liquid/ solvent layer, which is about 1.5 Watt for 5 cm height of liquid/ solvent layer.

Referring to FIG. 9C, there is shown yet another exemplary top view of an arrangement of packed bed assembly comprising: four units of inner structure packings (20) comprising first layer (20a), second layer (20b) and subsequent layers (hidden) disposed around one an ultrasonic fountain formation zone (31, crosshair area).

Referring to FIG. 10, there is shown a perspective view of a prototype ultrasonic packed bed showing upon an activation of sonication energy disposed at the bottom of the bed toward the solvent, causing the solvent flow path (F) upwardly from bottom of the bed then spiral downwardly back to the base (demarcated by arrows).

Referring to FIG. 11, there is shown a top view of the prototype ultrasonic packed bed. The structure packing guides the flow path of the solvent to maximize the absorption performance and solvent absorption capacity. Besides, the spent solvent can be discharged from the ultrasonic agitator efficiently.

Referring to FIG. 12, there is shown an internal view of prior art ultrasonic agitator disclosed in Malaysian application number PI 2015704436. Then referring to FIG. 13 illustrates an internal view of the assembly of ultrasonic packed bed (2) can be configured or disposed above the arrangement of at least one ultrasonic transducer (30) inside the reactor (40) to form the ultrasonic agitator (1), wherein said transducer (30) emits ultrasound energy, the ultrasound energy is configured to energize at resonant frequency to form at least one fountain of a second fluid in a continuous and controlled flow path (F) upwardly, through voids (6) of the assembly, then downwardly of the assembly, thereby enabling absorption, surface area, contact time, or mass transfer from a first fluid into the second fluid. The transducers (30) operate at 1 MHz or higher. The reactor (40) can be configured with at least one inlet for the first fluid (41) injecting fresh/ regenerated solvent, at least one outlet for the first fluid (42) discharging spent/ saturated/high loaded solvent, at least one inlet for the second fluid (43) injecting untreated hydrocarbon gas, flue gas, sour gas or a combination thereof, and at least one outlet for the second fluid (44) discharging treated hydrocarbon gas, flue gas, sour gas or a combination thereof. Referring to TABLE 1, there is shown types of targeted gas that contained in the first fluid such as natural gas, hydrocarbon gas, flue gas, sour gas, or the like, that can be removed by its corresponding liquid or solvent (second fluid). 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, NH ₃ 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 and alternative 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.