VALVE FOR CARRYING OUT A MASS TRANSFER PROCESS

Abstract

A valve accommodated in a separation tray including upper (3) and lower (5) trays, a lock (1) formed between the upper (3) and lower (5) trays. The valve (13) includes a closing element (11) configured such that an orifice (9) in the lower tray (5) is closed by the closing element (11) in a first valve position so that liquid flows from the upper tray (3) into the lock (1), and, in a second valve position, the orifice (9) and an orifice (7) in the upper tray (3) are opened so that gas flows through the lock (1) and liquid on the upper tray (3). The closing element (11) is in the form of a hood including a jacket (23) having orifices (21) positioned in such a way that, in the second valve position, gas flows through the orifices (21) into the liquid on the upper tray (3).

Claims

1. A valve for carrying out a mass transfer process, the valve accommodated in a separation tray comprising an upper tray and a lower tray, and a lock formed between the upper tray and the lower tray, the valve comprising: a closing element which is configured such that an orifice in the lower tray can be closed by means of the closing element in a first valve position so that liquid can flow from the upper tray into the lock, and, in a second valve position, the orifice in the lower tray is opened and an orifice in the upper tray is opened so that gas can flow through the lock and through liquid on the upper tray, wherein the closing element is in the form of a hood comprising a jacket having orifices positioned in such a way that, in the second valve position, gas can flow through the orifices into the liquid on the upper tray; and a chimney which is configured such that a cross section of the chimney is smaller than a cross section of the closing element and is connected to the lower tray and projecting into the lock, or is connected to the closing element.

2. The valve of claim 1, wherein a hood is formed on the upper tray such that the closing element abuts the hood on the upper tray in the second valve position.

3. The valve of claim 1, wherein the chimney is connected to the lower tray, and a stop is formed on the chimney such that the closing element abuts with a stop on the jacket.

4. The valve of claim 3, wherein the stop on the chimney is in the form of a bead or a ring-shaped widening at the upper end of the chimney.

5. The valve of claim 3, wherein the stop on the jacket is a peripheral rib at the lower end of the jacket.

6. The valve of claim 3, wherein the stop on the jacket comprises at least one pin.

7. The valve of claim 1, wherein a lower end of the chimney has a diametral widening.

8. The valve of claim 1, wherein the lower tray and the upper tray are connected to a sleeve, and the closing element is guided in the sleeve.

9. The valve of claim 8, wherein the chimney is connected to the closing element, and a stop is formed on the sleeve such that the closing element abuts the stop on the sleeve in the first valve position.

10. The valve of claim 8, wherein orifices are formed in the sleeve in the region of the lock, so that liquid can flow from the upper tray through the sleeve into the lock when the closing element is in the first valve position, and can flow out of the lock when the closing element is in the second valve position.

11. The valve of claim 1, wherein the chimney and the orifice in the lower tray are configured such that gas flows through the chimney from the bottom upward and liquid flows through the cross section of the orifice in the lower tray when the closing element is moved from the first valve position to the second valve position.

12. The valve of claim 1, wherein guide elements for the liquid are arranged at a lower end of the chimney.

Description

[0024] In these figures:

[0025] FIG. 1 shows a valve for a lock in a first embodiment,

[0026] FIG. 2 shows a valve according to FIG. 1 with additional guide elements for the liquid,

[0027] FIG. 3 shows a valve for a lock in a second embodiment, the closing element being in the first valve position,

[0028] FIG. 4 shows a valve for a lock in a second embodiment, the closing element being in the second valve position,

[0029] FIGS. 5A to 5G show different cross sections of the chimney,

[0030] FIG. 6 shows a stop for the closing element designed as a hood in a first embodiment,

[0031] FIG. 7 shows a stop for the closing element designed as a hood in a second embodiment,

[0032] FIG. 8 shows a lower portion of the chimney with a diametral widening,

[0033] FIG. 9 shows a valve with a closing element in a third embodiment.

[0034] FIG. 1 illustrates a valve for a lock, such as is used in columns for cyclic mass transfer processes.

[0035] A lock 1 for a column for cyclic mass transfer processes comprises an upper tray 3 and a lower tray 5. Located both in the upper tray 3 and in the lower tray 5 in each case is at least one orifice 7, 9, through which liquid can flow downward and gas can flow upward. The orifice 7 in the upper tray 3 and the orifice 9 in the lower tray 5 are arranged in alignment one above the other, so that a closing element 11 of a valve 13, which connects the upper tray 3 and the lower tray 5, can be moved through the orifices 7, 9 into the trays 3, 5. According to the invention, the closing element 11 is configured in the form of a hood.

[0036] According to the invention, the valve 13 comprises a chimney 15 which is connected firmly to the lower tray 5 and the orifice cross section of which is smaller than the orifice cross section of the orifice 9 in the lower tray. In the embodiment illustrated here, the chimney 15 has at its upper end a ring-shaped widening 17, the diameter of which corresponds to the inside diameter of the closing element 11 designed as a hood. At the start of gas supply, the ring-shaped widening 17 prevents gas from being able to flow into the lock when the closing element 11 designed as a hood is raised. The gas pressure below the closing element 11 designed as a hood is consequently kept sufficiently high to raise the closing element 11 designed as a hood into the second valve position.

[0037] So that the closing element 11 designed as a hood can be raised in a fault-free manner and liquid does not flow out of the lock 1 immediately upon the commencement of the lifting movement of the closing element 11 designed as a hood, in the first valve position the chimney 15 and the closing element 11 designed as a hood project by a distance h into the space below the lower tray 5. When gas flow commences, the gas first flows only through a lower orifice 25 into the chimney and consequently exerts a sufficiently high force upon the closing element 11 designed as a hood to raise the latter out of the first valve position. As soon as the closing element 11 designed as a hood has been raised over the distance h, liquid can flow from the lower tray 5 out of the lock. In this case, the liquid flows through the orifice 9 outside the chimney 15. As a result of a ring-shaped widening 19 at the lower end of the chimney 15, the liquid is defected, so that it does not directly counteract the gas flow directed into the chimney. So that the outflowing liquid does not give rise in the lock 1 to a vacuum which at the same time obstructs the further outflow of liquid, the closing element 11 designed as a hood has provided in it orifices 21 through which gas can flow out of the closing element 11 designed as a hood into the lock 1 as soon as the closing element designed as a hood has been raised over the distance h. For this purpose, the orifices 21 are arranged in the jacket 23 of the closing element 11 designed as a hood, such that the top edge of the orifices 21 lies by the amount of the distance h below the upper end of the chimney 15 when the closing element 11 designed as a hood is in the first valve position.

[0038] So that the closing element 11 designed as a hood, when it moves out of the first valve position into a second valve position, is moved only in the axial direction and is not tilted, in the embodiment illustrated here the closing element 11 designed as a hood is guided in a sleeve 27. So as not to obstruct the liquid flow and gas flow, the sleeve 27 has formed in it, below the lower tray 5, lower orifices 29 through which the liquid can flow out of the lock 1 into the space lying underneath. At the same time, the sleeve 27 and the ring-shaped widening 19 at the lower end of the chimney 15 also serve for holding the chimney 15 in position. For this purpose, the sleeve 27 projects over the distance h into the space below the lower tray 5. So that gas and liquid can flow into and out of the sleeve 27 in the region of the lock 1, orifices 31 are likewise formed in the sleeve 27 inside the lock 1.

[0039] In the embodiment illustrated in FIG. 1, the sleeve 27 projects in the form of a hood 33 into a space above the upper tray 3. An upper stop for the closing element 11 designed as a hood is thereby formed, which limits the movement of the closing element 11 designed as a hood in the second valve position. The sleeve 27 has formed in it, above the upper tray 3, upper orifices 35 through which liquid can flow from the upper tray into the lock as soon as the gas flow is no longer sufficiently strong to obstruct the outflow of liquid from the upper tray 3. So that mass transfer can take place, the stop for the closing element 11 designed as a hood is designed, in the second valve position, such that the orifices 21 in the closing element 11 designed as a hood lie above the upper tray 3 in the second valve position, the lower edge of the orifices 21 preferably terminating flush with the upper tray 3. In the second valve position, gas thereby flows through the orifices 21 in the jacket 23 of the closing element 11 designed as a hood and through the upper orifices 35 in the sleeve 27 into the liquid of the upper tray 3, so that intensive mass transfer takes place between gas and liquid of the upper tray 3.

[0040] In a cyclic mass transfer process, the gas supply is interrupted after a stipulated time and the entire liquid of a separation tray is conducted onto a separation tray lying underneath. So that remixing does not occur in this case, the liquid first flows into the lock 1 and, after a renewed start of the gas supply, from there onto the separation tray lying underneath. During the mass transfer process, the closing element 11 of the valve 13 is in the second valve position. When the gas flow is terminated, the closing element 11 falls into the first valve position in which the orifice 9 in the lower tray 5 of the lock 1 is closed. So that no liquid can flow out from the upper tray 3 through the lock 1 into the space below the lock 1 during the lifting movement of the closing element 11 out of the second valve position into the first, the orifices 31 in the sleeve 27 are designed such that the spacing of the top edge of the orifices 31 from the upper end of the chimney 15 corresponds to the distance h. Liquid can consequently flow through the orifices 31 into the lock 1 only when the lower edge of the jacket 23 of the closing element 11 designed as a hood closes the orifice 9 in the lower tray 5. This ensures that, when the gas supply is interrupted, the entire liquid from the upper tray 3 is first collected in the lock 1 and cannot flow out through the orifice 9 in the lower tray 5.

[0041] FIG. 2 shows a valve for a lock with additional guide elements for the liquid.

[0042] The valve illustrated in FIG. 2 corresponds in its set-up essentially to that illustrated in FIG. 1. In contrast to the valve illustrated in FIG. 1, it additionally comprises guide elements in the form of outflow gutters 38 which are arranged at the lower end of the chimney 15. For this purpose, the outflow gutters 38 adjoin the ring-shaped widening 19. By means of the outflow gutters 38, the liquid is conducted away from the lower orifice 25 through which the gas flows. The advantage of this is that the liquid flows out in a region in which the gas velocity is so low that no liquid drops are entrained. For this purpose, as in the embodiment illustrated here, the outflow gutters 38 are preferably oriented obliquely downward at an angle, the run of the outflow gutters 38 extending away from the lower orifice 25. The cross section of the outflow gutters 38 may, for example, be u-shaped, v-shaped or preferably rectangular, the outflow gutters 38 preferably being open upwardly.

[0043] Guide elements of this type, for example outflow gutters 38, may be used whenever the chimney is connected firmly to the lower tray 5 of the lock 1, as is also the case in the embodiments shown in FIGS. 6 and 7. In embodiments, such as those shown below in FIGS. 3, 4 and 9 in which the chimney is connected to the closing element, corresponding guide elements may be dimensioned or mounted merely such that the function of the valve is not obstructed as a result.

[0044] A second embodiment of a valve for a lock in a column for cyclic mass transfer processes, in a first valve position, is illustrated in FIG. 3. FIG. 4 shows the closing element according to the embodiment illustrated in FIG. 3 in a second valve position.

[0045] In contrast to the embodiment illustrated in FIG. 1, in the embodiment shown in FIGS. 3 and 4 the chimney 15 is connected to the closing element 11 designed as a hood. So that, when the outflow of liquid from the lock 1 commences, the orifice 9 in the lower tray 5 is not filled completely with liquid, so that the gas flow is interrupted or weakened, the chimney 15 is in this case longer than the jacket 23 of the closing element 11 designed as a hood. As a result, the liquid first flows through the cross section, not filled by the chimney 15, of the orifice 9 in the lower tray 5, and the gas can still flow through the orifice 25 into the chimney 15.

[0046] When the gas supply is interrupted, the closing element 11 designed as a hood is in the first valve position illustrated in FIG. 3. Since the jacket of the closing element 11 designed as a hood projects downward through the orifice 9 in the lower tray 5, the orifice 9 is closed, so that no liquid can flow out of the lock 1 into space lying below the lock. All the orifices which would enable the liquid to flow out of the lock are closed.

[0047] When the gas supply is restarted, the closing element 11 designed as a hood is raised by gas flowing into the chimney 15 and into the interspace between chimney 15 and jacket 23. Since the jacket 23 projects downward through the lower tray 5 into the space underneath the lock 1, the closing element 11 designed as a hood first has to be raised until the lower end of the jacket 23 is above the lower tray 5, so that the liquid can flow out of the lock. For this purpose, as may be gathered from FIG. 4, orifices 36 are formed in the sleeve 27 directly above the lower tray 5. The liquid can flow through these orifices 36 in the sleeve 27 through the orifice cross section, not filled by the chimney 15, of the orifice 9 in the lower tray 5 and out of the lock 1. Since the chimney 15 projects downward out of jacket 23 of the closing element 11 designed as a hood, gas can still flow into the chimney 15 and raise the closing element 11 further, while at the same time the liquid flows out of the lock 1 into the space lying underneath. Since the liquid starts to flow out of the lock 1 only after the closing element 11 is already in movement, this ensures that the entire liquid remains on the upper tray 3 of the next lower lock and no liquid flows out further through the next lower lock while the gas supply is being started. The mass transfer process can thereby be further optimized.

[0048] So that the liquid can flow out of the lock 1 during the lifting movement of the closing element 11 and no vacuum is formed in the lock, which would cause liquid to be sucked into the lock and the outflow of liquid thereby interrupted, orifices 21 are formed in the jacket 23 of the closing element 11 designed as a hood and orifices 37 are formed in the chimney 15. Both the orifices 21 in the jacket 23 and the orifices 37 in the chimney are in this case preferably arranged in the upper region of the closing element 11 designed as a hood. As soon as the orifices 21 in the jacket 23 overlap orifices 31 in the upper region of the sleeve 27, gas can flow out of the chimney and out of the region below the jacket 23 through the orifices 21, 31 into the lock in order to compensate the pressure.

[0049] As a result of the gas flow, the closing element 11 designed as a hood is raised further until it has reached the second valve position illustrated in FIG. 4. In the second valve position, the orifices 21 are located at least partially above the upper tray 3, so that the gas can flow out through the orifices 21 into the space above the upper tray 3. Since liquid is located on the upper tray during the mass transfer process, the gas is conducted through the liquid.

[0050] As soon as the gas supply is interrupted again, the closing element 11 designed as a hood falls again into the first valve position illustrated in FIG. 3, with the result that the orifice 7 in the upper tray is released, so that the liquid can flow out from the upper tray through the orifices 31 in the sleeve 27 into the lock.

[0051] So that, during the lifting movement of the closing element 11, the gas flow is not obstructed by liquid flowing out of the lock 1 and at the same time the liquid is not prevented by the gas flow from flowing out of the lock 1, the chimney 15 is configured such that it fills only part of the orifice cross section of the orifice 9 in the lower tray 5. Possible variants for the configuration of the orifice 25 of the chimney 15 are illustrated in FIGS. 5A to 5G. In this case, the orifice 9 in the lower tray 5 is in each case of circular shape. However, in addition to the circular shape, illustrated here, for the orifice 9, the orifice 9 may also assume any other cross section.

[0052] In the embodiment illustrated in FIG. 5A, the chimney 15 likewise has a circular cross section. The chimney 15 is in this case arranged concentrically in the orifice 9. However, an eccentric arrangement would likewise be possible. It would also be possible to configure the chimney with a cross-sectional surface in another shape, for example as a polygon with at least three corners, as an ellipse or in any other form. What must simply be remembered is that the cross-sectional surface of the orifice 25 of the chimney 15 is smaller than the cross-sectional surface of the orifice 9 in the lower tray 5, and that the maximum extents are selected such that the chimney 15 does not intersect the orifice 9, but is located completely in the orifice 9.

[0053] Different variants in which the chimney is configured in the form of a segment of a circle are illustrated in FIGS. 5B, 5C and 5D. In this case, in FIG. 5B the cross-sectional surface of the orifice 25 in the chimney is larger than the free cross-sectional surface 39 of the orifice 9, in the embodiment illustrated in FIG. 5C the cross-sectional surface of the orifice 25 in the chimney is smaller than the free cross-sectional surface 39 of the orifice 9, and in the embodiment illustrated in FIG. 5D the two cross-sectional surfaces 25, 39 are of equal size.

[0054] In the embodiment shown in FIG. 5E, the chimney has a cross section in the form of two circle sectors. Alternatively, it is also possible to configure the chimney with a cross section of only one circle sector or else of a plurality of circle sectors. Nor is it necessary for the circle sectors to have in each case a center angle of 90. The center angle of the individual circle sectors may assume any other value. It is merely necessary to ensure that the overall cross-sectional surface of the orifice 25 of the chimney 15 is smaller than the overall cross-sectional surface of the orifice 9 in the lower tray 5.

[0055] In the embodiments illustrated in FIGS. 5F and 5G, in FIG. 5F the cross section 39, not filled by the chimney 15, of the orifice 9 is configured in the form of two axially symmetrical segments of a circle which lie opposite one another, and in the embodiment illustrated in FIG. 5G the chimney 15 is, mirror-inverted, in the form of the two axially symmetrical segments of a circle which lie opposite one another.

[0056] In FIGS. 5A to 5G, the free cross-sectional surface 39 is in each case the cross-sectional surface of the orifice 9 through which the liquid flows out of the lock 1.

[0057] So that the closing element 11 designed as a hood remains respectively in the first and the second valve position, it is necessary in each case to provide a stop which limits the lifting movement of the closing element 11 designed as a hood.

[0058] If the chimney 15 is connected to the lower tray 5 via the sleeve 27, the lower stop for limiting the lift in the first valve position is implemented by the ring-shaped widening 19 at the lower end of the chimney 15.

[0059] As illustrated in FIG. 1, the upper stop can be implemented in the form of a hood 33 above the upper tray 3. Alternatively, it is also possible to use the ring-shaped widening 17 at the upper end of the chimney 15 as a stop for the second valve position. This is illustrated, for example, in FIGS. 6 and 7.

[0060] In the embodiment illustrated in FIG. 6, a flanged edge 41 is shaped at the lower end of the jacket 23 of the closing element 11 designed as a hood. In the second valve position, the closing element 11 designed as a hood abuts with the flanged edge 41 against the ring-shaped widening 17 at the upper end of the chimney 15, so that the lifting movement of the closing element is limited upwardly.

[0061] Alternatively, a bead 43 may also be shaped in the jacket 23 of the closing element designed as a hood and abuts against the ring-shaped widening 17 of the chimney 15 in order to limit the lifting movement in the second valve position. This is illustrated, for example, in FIG. 7.

[0062] Since, in the embodiment illustrated in FIGS. 3 and 4, the chimney 15 cannot be used as a stop, it is possible here, for example, to shape the upper and the lower stop for limiting the lift in the sleeve 27. The stop can in this case likewise be implemented in the form of a flanged edge or a bead or in the form of pins.

[0063] An embodiment in which the chimney 15 has at the lower end a diametral widening 45 which runs without an edge is illustrated in FIG. 8. In contrast to the embodiment illustrated in FIGS. 1, 6 and 7 with a ring-shaped widening 19 at the lower end of the chimney 15, in the embodiment illustrated in FIG. 8 the diameter increases continuously. This avoids a sharp edge at which dead spaces may form, in which, in turn, deposits may occur. As a result of the continuous increase in diameter, the liquid can be deflected smoothly. The continuous increase in diameter may in this case be implemented, for example, as a radius, as illustrated here. Alternatively, a parabolic, elliptic or hyperbolic diameter increase would also be conceivable.

[0064] A further embodiment of a valve with a chimney 15 integrally formed on the closing element 11 designed as a hood is illustrated in FIG. 9.

[0065] In contrast to the embodiment illustrated in FIGS. 3 and 4, in the embodiment illustrated in FIG. 9 the chimney 15 is formed below the jacket 23 of the closing element 11 designed as a hood. The chimney is in this case formed by a diametral narrowing of the jacket 23.

[0066] In the embodiment illustrated in FIG. 9, the jacket 23 of the closing element 11 designed as a hood is configured such that, in the first valve position, lower orifices 29 below the lower tray 5 and orifices 36 directly above the lower tray 5, in a sleeve surrounding the closing element 11 designed as a hood, are closed, in order thereby to prevent the outflow of liquid from the lock 1. During the lifting movement of the closing element 11 designed as a hood into the second valve position, the chimney 15 formed the lower end of the jacket 23 moves in the direction of the lower orifices 29 and the orifices 36 directly above the lower tray 5. As soon as the chimney has reached the orifices 36 above the lower tray 5, the liquid can flow out of the lock through the orifices 36 and the lower orifices 29. At the same time, gas can flow out of the closing element 11 designed as a hood through orifices 21 in the jacket and orifices 31 in the upper region of the sleeve 27 within the lock 1 into the lock 1. As soon as the closing element 11 has reached the second valve position, the gas flows through the orifices 21 in the jacket 23 of the closing element 11 designed as a hood and through the upper orifices 25 in the sleeve 27 into the liquid on the upper tray 3. The lifting movement of the closing element 11 designed as a hood in the second valve position is in this case limited by a flanged edge 47 at the upper end of the sleeve 27 projecting into the space above the upper tray 3.

[0067] The stop in the first valve position is implemented by a flanged edge 49 which is formed at the lower end of the sleeve 27 projecting into the space below the lower tray 3. In this case, the chimney, optionally with a ring-shaped widening 19, abuts against the flanged edge 49 in order to limit the lifting movement in the first valve position downwardly.

[0068] Alternatively to the flanged edge 47, 49 at the upper and at the lower end of the sleeve 27, any other form of a stop may also be provided, for example a bead or pins which project into the sleeve 27. The stop for the second valve position above the upper tray 3 may also be implemented in the form of a hood, as illustrated in FIG. 1.

[0069] In all the embodiments illustrated, it is preferable, furthermore, if the hood 11 has formed in it, above the maximum liquid level in the lock 1, a bore, by means of which pressure compensation can take place when the closing element is in the lower position and the gas flow through the column is thereby interrupted.

LIST OF REFERENCE SYMBOLS

[0070] 1 lock [0071] 3 upper tray [0072] 5 lower tray [0073] 7 orifice in the upper tray 3 [0074] 9 orifice in the lower tray 5 [0075] 11 closing element [0076] 13 valve [0077] 15 chimney [0078] 17 ring-shaped widening at the upper end of the chimney 15 [0079] 19 ring-shaped widening at the lower end of the chimney 15 [0080] 21 orifice [0081] 23 jacket [0082] 25 lower orifice in the chimney 15 [0083] 27 sleeve [0084] 29 lower orifice [0085] 31 orifice in the sleeve 27 [0086] 33 hood [0087] 35 upper orifice [0088] 36 orifice in the sleeve 27 [0089] 37 orifice in the chimney 15 [0090] 38 outflow gutter [0091] 39 cross section not filled by the chimney 15 [0092] 41 flanged edge [0093] 43 bead [0094] 45 diametral widening [0095] 47 flanged edge [0096] 49 flanged edge