DEVICE FOR HEAT TRANSFER BETWEEN A LIQUID AND A GAS AND METHOD FOR OPERATING THE DEVICE

Abstract

A device for heat transfer between a liquid and a gas, having: a gas inlet for providing the gas into an exchange region, a gas outlet for retrieving the gas from the exchange region, a liquid inlet connected to a reservoir for holding the liquid. The reservoir is formed with an opening in an upper region of the reservoir, the reservoir is arranged at an upper end of the exchange region, an impounding basin. The impounding basin is arranged below the reservoir, the impounding basin is formed with a liquid outlet, and an exchange element arranged in the exchange region. An upper part of the exchange element is disposed through the opening of the reservoir such that the upper part of the exchange element is arranged at least partially inside the reservoir and such that the upper part of the exchange element is at least partially submerged in the liquid.

Claims

1. A device for heat transfer between a liquid and a gas, comprising: a gas inlet for providing the gas into an exchange region, a gas outlet for retrieving the gas from the exchange region, a liquid inlet connected to a reservoir for holding the liquid, wherein the reservoir is formed with an opening in an upper region of the reservoir, and wherein the reservoir is arranged at an upper end of the exchange region, an impounding basin, wherein the impounding basin is arranged below the reservoir, and wherein the impounding basin is formed with a liquid outlet, and an exchange element arranged in the exchange region, wherein an upper part of the exchange element is disposed through the opening of the reservoir such that the upper part of the exchange element is arranged at least partially inside the reservoir and such that the upper part of the exchange element is at least partially submerged in the liquid.

2. The device of claim 1, wherein a lower part of the exchange element is arranged at least partially inside the impounding basin.

3. The device of claim 1, wherein the exchange element is tubular.

4. The device of claim 3, wherein a supporting element is arranged inside the tubular exchange element.

5. The device of claim 4, wherein the supporting element is a tube.

6. The device of claim 4, wherein the supporting element is formed with a perforated surface.

7. The device of claim 4, wherein the supporting element is a spiral.

8. The device of claim 3, wherein a heat exchanger element is arranged inside the tubular exchange element.

9. The device of claim 3, wherein a lower end of the tubular exchange element is connected to a perforated plate, and wherein the gas inlet is configured to provide a flow of gas through the perforated plate inside the tubular exchange element.

10. The device of claim 1, wherein the exchange element is flat.

11. The device of claim 1, wherein the exchange element is formed with two layers, wherein a separation element is arranged in the exchange region, and wherein the two layers of the exchange element are separated in the exchange region by the separation element.

12. The device of claim 11, wherein the two layers of the exchange element are arranged parallel to each other in the exchange region by the separation element.

13. The device of claim 10, wherein a heat exchanger element is exposed to the flat exchange element.

14. The device of claim 1, wherein the exchange element is made of an absorbent material.

15. A method for operating a heat transfer device, wherein the heat transfer device comprises: a gas inlet, a gas outlet, a liquid inlet connected to a reservoir for holding the liquid, wherein the reservoir is formed with an opening in an upper region of the reservoir, and wherein the reservoir is arranged at an upper end of the exchange region, an impounding basin, wherein the impounding basin is arranged below the reservoir, and wherein the impounding basin is formed with a liquid outlet, and an exchange element arranged in the exchange region, and wherein the method comprises steps of: disposing an upper part of the exchange element through the opening of the reservoir such that the upper part of the exchange element is arranged at least partially inside the reservoir, filling the reservoir at least partially with the liquid such that the upper part of the exchange element is at least partially submerged in the liquid and a flow of liquid along the exchange element is created, providing, by the gas inlet, the gas into the exchange region, such that the gas is in direct contact with the liquid in the exchange element, and retrieving, by the gas outlet, the gas from the exchange region.

16. The device of claim 2, wherein the exchange element is tubular.

17. The device of claim 5, wherein the supporting element is formed with a perforated surface.

18. The device of 4, wherein a heat exchanger element is arranged inside the tubular exchange element.

19. The device of 4, wherein the exchange element is made of an absorbent material.

20. The device of 2, wherein the exchange element is flat.

Description

DESCRIPTION OF EMBODIMENTS

[0028] In the following, embodiments are described with reference to figures of a drawing.

[0029] FIG. 1 shows a first embodiment of a device for heat transfer between a liquid and a gas.

[0030] FIG. 2 shows a second embodiment of a device for heat transfer between a liquid and a gas.

[0031] FIG. 3 shows a third embodiment of a device for heat transfer between a liquid and a gas.

[0032] In the following, same reference numbers are used for same components.

[0033] FIG. 1 shows a first embodiment of a heat (and mass) transfer device. The device comprises a duct 3. The reservoir 7, the exchange element 11 and the impounding basin 9 are arranged within the duct 3. A gas inlet 4 is formed in a lower region of the duct 3. A gas outlet 5 is formed at an upper region of the duct 3. A gas stream flows from the gas inlet 4 to the gas outlet 5.

[0034] In an upper part of the device, a reservoir 7 is arranged which is in connection to a liquid inlet 6. A liquid impounding basin 9 is arranged below the reservoir 7. An exchange element 11 (also called wet pad) is arranged between the reservoir 7 and the impounding basin 9. An upper part 11a of the exchange element is disposed through an opening 20 of the reservoir 7 such that the upper part 11a is arranged inside the reservoir 7. The upper part 11a may touch a bottom of the reservoir. Liquid 2 is filled in the reservoir via the liquid inlet 6. When the liquid 2 contacts the upper part 11a of the exchange element 11, capillary forces draw the liquid along the exchange element (against the force of gravity). By controlling the fill level of the reservoir, the strength of the capillary forces is determined. Liquid flows along the upper part 11a of the exchange element 11 until it reaches the opening 20. The opening 20 provides an overflow 8. After the liquid 2 passes the opening 20 (and overflow 8), it is drawn by gravitation downwards the exchange element 11. The liquid 2 is gathered in the impounding basin 9 which is formed with a liquid outlet 10 for retrieving the liquid 2. A lower part 11c of the exchange element 11 is arranged in the impounding basin 9. Hereby, formation of droplets is avoided.

[0035] A stream of gas is provided by a gas inlet 4. The gas streams along the exchange elements where it is in direct contact with the liquid. Heat (and mass) can be exchanged between the gas and the liquid. The gas is retrieved from the device by a gas outlet 5.

[0036] Another embodiment of the device is shown in FIG. 2. Several exchange elements are arranged in the exchange region. Further, a separation element 16 is provided. The exchange elements 11 are each formed by two layers of a material (e.g. a textile). The two layers are put together in the upper part of the exchange elements. Inside the exchange region, the two layers are separated by the separation element 16 such that the two layers of each exchange element 11ba, 11bb hang parallel to each other.

[0037] FIG. 3 shows another embodiment. The exchange element 11 is tubular at least in the exchange region below the reservoir 7. A supporting element 14 is arranged inside the tubular exchange element 11 in order to support the separation of the walls of the exchange element. The supporting element 14 can be a perforated tube. At a lower end of the duct 3, a perforated plate 15 is arranged. The exchange element 11 is positioned such that the lower end of the exchange element fits through an opening of the perforated plate 15. Gas 1 provided by the gas inlet 4 flows through the lower part of the exchange element 11 and then further inside the supporting element 14 along the exchange region, being in direct contact with the liquid here. The gas may leave the tubular exchange element 11 through openings in the supporting element 14 and through the permeable structure of the exchange element 11.

[0038] A pump 12 is connected to the liquid inlet 6. Hereby, the amount of liquid transported to the reservoir 7 can be controlled. The liquid outlet 10 is connected with the liquid inlet 6 providing a liquid circuit.

[0039] The features disclosed in the specification, the claims and the figures can be relevant for implementing embodiments, either alone or in any possible combination of each other.