WO2022158925A1

WO2022158925A1 - Laundry treating apparatus and method for controlling the same

Info

Publication number: WO2022158925A1
Application number: PCT/KR2022/001209
Authority: WO
Inventors: Jooseong LEE; Yanggyu Kim; Jangseok Lee
Original assignee: Lg Electronics Inc.
Priority date: 2021-01-25
Filing date: 2022-01-24
Publication date: 2022-07-28
Also published as: KR102594903B1; KR20220107552A

Abstract

The present disclosure relates to a laundry treating apparatus including a pressure vessel for accommodating carbon dioxide, a storage tank for storing carbon dioxide therein to supply carbon dioxide to the pressure vessel, a distillation tank for accommodating carbon dioxide discharged from the pressure vessel to remove foreign substances dissolved in carbon dioxide discharged from the pressure vessel, a recovery flow path located outside the pressure vessel to circulate gaseous carbon dioxide of the pressure vessel, and a recovery heat exchanger located on the recovery flow path to exchange heat with gaseous carbon dioxide passing through the recovery flow path to liquefy gaseous carbon dioxide.

Description

LAUNDRY TREATING APPARATUS AND METHOD FOR CONTROLLING THE SAME

The present disclosure relates to a laundry treating apparatus. More particularly, the present disclosure relates to a laundry treating apparatus that performs laundry treatment such as washing or the like using carbon dioxide as a washing solvent and a method for controlling the same.

A laundry treating apparatus may perform washing and drying laundry at home or in other places, and can remove wrinkles on the laundry. For example, the laundry treating apparatus can include a washing machine that washes the laundry, a dryer that dries the laundry, a washing machine/dryer that has both a washing function and a drying function, a laundry manager that refreshes the laundry, a steamer that removes the wrinkles from the laundry, and the like.

Recently, Carbon dioxide (CO2) may be used as a new cleaning solvent. Carbon dioxide is a colorless and odorless gas at an ambient pressure and at a room temperature, and carbon dioxide may evaporate when a washing process at a high pressure is completed and the pressure is lowered to the atmospheric pressure, which may obviate the need for a separate drying cycle. In addition, as carbon dioxide is one of components of general atmosphere, carbon dioxide may not pollute the environment.

In addition, when using a distillation tank, carbon dioxide contaminated after the washing may be reused by removing only the foreign substances from the contaminated carbon dioxide and then distilling the contaminated carbon dioxide into clean carbon dioxide. To this end, only liquid carbon dioxide in which the foreign substances are dissolved is vaporized to be separated from the foreign substances, and then, the vaporized pure liquid carbon dioxide is liquefied again and used.

For such distillation, a carbon dioxide compressor that compresses gaseous carbon dioxide at high temperature and pressure is required. This is to continuously vaporize the liquid carbon dioxide through heat exchange between the high-temperature gaseous carbon dioxide and the liquid carbon dioxide in which the foreign substances are dissolved. In addition, in order to recover gaseous carbon dioxide remaining in a washing chamber or a pressure vessel after distillation, the carbon dioxide compressor should be used.

European Patent EP2576886B1 discloses a distillation operation and a recovery operation using the carbon dioxide compressor. However, in order to compress carbon dioxide, there is a problem in that energy consumption is large and a compressor having a large size must be used to compress the carbon dioxide at once because a pressure difference before and after the compression is large.

US Patent No. US10352591B2 discloses a laundry treating apparatus that efficiently utilizes energy using two-stage compression. However, because of characteristics of the compressor, oil for lubrication of the compressor or other impurities occurred by friction may be mixed with the carbon dioxide. This has a problem that ultimately degrades a washing performance.

First, the present disclosure is to make oil for lubrication, other frictional impurities, or the like not enter a carbon dioxide compressor due to use of the carbon dioxide compressor.

Second, the present disclosure is to utilize a compressor that compresses a refrigerant, which is small in size unlike carbon dioxide, in a distillation operation and a recovery operation of recovering gaseous carbon dioxide after the distillation operation.

Third, the present disclosure is to minimize energy consumption during vaporization of liquid carbon dioxide and flow and liquefaction of vaporized carbon dioxide in a distillation operation.

Fourth, the present disclosure is to distill carbon dioxide using a thermosiphon phenomenon.

In order to solve the above problems, a laundry treating apparatus according to the present disclosure may use a compressor for compressing a refrigerant instead of a compressor for compressing gaseous carbon dioxide. In addition, by installing heat exchangers respectively in a storage tank and a distillation tank, vaporization of liquid carbon dioxide in the distillation tank is made through heat exchange with a refrigerant compressed at high temperature and pressure, and vaporization of gaseous carbon dioxide in the storage tank is made through heat exchange with a refrigerant cooled after expansion.

In addition, flow from the storage tank to the distillation tank may be made without a separate fluid flowing apparatus such as a pump or a compressor.

To this end, provided is a laundry treating apparatus including a pressure vessel for maintaining carbon dioxide accommodated therein at a pressure higher than an atmospheric pressure, a storage tank for storing carbon dioxide therein to supply carbon dioxide to the pressure vessel, a distillation tank for storing therein carbon dioxide discharged from the pressure vessel to remove foreign substances dissolved in carbon dioxide discharged from the pressure vessel, a recovery flow path located outside the pressure vessel to circulate gaseous carbon dioxide of the pressure vessel, and a recovery heat exchanger located on the recovery flow path to exchange heat with gaseous carbon dioxide passing through the recovery flow path to liquefy gaseous carbon dioxide.

The laundry treating apparatus may further include a recovery body positioned on the recovery flow path to accommodate the recovery heat exchanger therein and store carbon dioxide liquefied through the recovery heat exchanger therein.

The laundry treating apparatus may further include a recovery tank positioned between the pressure vessel and the distillation tank to store liquefied carbon dioxide therein.

The laundry treating apparatus may further include a recovery compressor for compressing and circulating a refrigerant to exchange heat with gaseous carbon dioxide through the recovery heat exchanger, and a recovery fan positioned on the recovery flow path to circulate gaseous carbon dioxide of the pressure vessel.

The laundry treating apparatus may further include a first recovery pipe for connecting the recovery flow path and the recovery tank to each other to flow the liquefied carbon dioxide, and a first recovery valve positioned on the first recovery pipe to open and close the first recovery pipe.

The laundry treating apparatus may further include a second recovery pipe for connecting the recovery tank and the distillation tank to each other to flow gaseous carbon dioxide of carbon dioxide stored in the distillation tank, a second recovery valve positioned on the second recovery pipe to open and close the second recovery pipe, a third recovery pipe for connecting the recovery tank and the distillation tank to each other to flow liquid carbon dioxide of carbon dioxide stored in the recovery tank, and a third recovery valve located on the third recovery pipe to open and close the third recovery pipe.

The laundry treating apparatus may further include a distillation heat exchanger located inside the distillation tank to exchange heat with carbon dioxide stored inside the distillation tank, a storage heat exchanger located inside the storage tank to exchange heat with carbon dioxide stored in the storage tank, a distillation compressor for compressing the refrigerant circulating through the distillation heat exchanger and the storage heat exchanger, and a distillation refrigerant flow path for connecting the distillation heat exchanger, the storage heat exchanger, and the distillation compressor to each other to form a flow path for circulating the refrigerant therethrough.

The distillation heat exchanger may be located inside the distillation tank at a lower portion of the distillation tank, and the storage heat exchanger may be located inside the storage tank at an upper portion of the storage tank.

The laundry treating apparatus may further include a distillation expander for expanding the refrigerant that has passed through the distillation heat exchanger on the distillation refrigerant flow path.

The distillation refrigerant flow path may include a first circulation pipe for connecting the distillation compressor and the distillation heat exchanger to each other to flow the refrigerant compressed in the distillation compressor to the distillation heat exchanger, a second circulation pipe for connecting the distillation heat exchanger and the distillation expander to each other to flow the refrigerant that has exchanged heat with carbon dioxide stored in the distillation tank from the distillation heat exchanger to the distillation expander, a third circulation pipe for connecting the distillation expander and the storage heat exchanger to each other to flow the refrigerant cooled through the distillation expander to the storage heat exchanger, and a fourth circulation pipe for connecting the storage heat exchanger and the distillation compressor to each other to flow the refrigerant that has exchanged heat with carbon dioxide stored in the storage tank from the storage heat exchanger to the distillation compressor.

A temperature of the refrigerant passing through the second circulation pipe may be higher than a temperature of the refrigerant passing through the third circulation pipe.

A temperature of the refrigerant passing through the distillation heat exchanger may be higher than a temperature of the refrigerant passing through the storage heat exchanger.

The laundry treating apparatus may further include a storage pipe for connecting the distillation tank and the storage tank to each other to flow gaseous carbon dioxide stored in the distillation tank to the storage tank.

The storage pipe may connect a top of the distillation tank and a top of the storage tank to each other.

In one example, provided is a method for controlling a laundry treating apparatus including a pressure vessel for maintaining carbon dioxide accommodated therein at a pressure higher than an atmospheric pressure, a drum rotatably disposed inside the pressure vessel to accommodate laundry therein, a storage tank for storing carbon dioxide therein to supply carbon dioxide to the pressure vessel, and a distillation tank for storing therein carbon dioxide discharged from the pressure vessel to remove foreign substances dissolved in carbon dioxide discharged from the pressure vessel including a rinsing operation of removing the foreign substances by rotating the drum at a preset rotation speed and using friction between liquid carbon dioxide supplied from the storage tank and the laundry, a discharge operation of discharging liquid carbon dioxide used in the pressure vessel to the distillation tank when the rinsing operation is completed, and a recovery operation of liquefying gaseous carbon dioxide remaining in the pressure vessel through heat exchange with a recovery flow path for circulating gaseous carbon dioxide to the outside of the pressure vessel and a recovery heat exchanger located on the recovery flow path, and then, storing liquefied carbon dioxide in a recovery tank located between the pressure vessel and the distillation tank.

The method may further include a distillation operation of, after the discharge operation, vaporizing liquid carbon dioxide stored in the distillation tank through heat exchange with a distillation heat exchanger located in the distillation tank and flowing the vaporized carbon dioxide to the storage tank, and liquefying gaseous carbon dioxide stored in the storage tank through heat exchange with a storage heat exchanger located in the storage tank.

First, the present disclosure may make the oil for the lubrication, other frictional impurities, or the like not enter the carbon dioxide compressor due to the use of the carbon dioxide compressor.

Second, the present disclosure may utilize the compressor that compresses the refrigerant, which is small in size unlike the carbon dioxide, in the distillation operation and the recovery operation of recovering the gaseous carbon dioxide after the distillation operation.

Third, the present disclosure may minimize the energy consumption during the vaporization of the liquid carbon dioxide and the flow and the liquefaction of the vaporized carbon dioxide in the distillation operation.

Fourth, the present disclosure may distill the carbon dioxide using the thermosiphon phenomenon.

(a) and (b) in FIG. 1 show an example of a laundry treating apparatus described in the present disclosure.

FIG. 2 shows an example of a drum and a driver disposed inside a pressure vessel.

(a) and (b) in FIG. 3 are a front view and a side view of a partition wall, respectively.

FIG. 4 shows components of a conventional laundry treating apparatus using carbon dioxide as a washing solvent.

(a) in FIG. 5 shows flow of heat in a distillation operation in a conventional laundry treating apparatus. (b) in FIG. 5 shows flow of heat in a distillation operation using a thermosiphon phenomenon. (c) in FIG. 5 shows a distillation operation and a recovery operation using a thermosiphon phenomenon.

FIG. 6 is a schematic diagram of circulation of a refrigerant during a distillation operation proceeding in a laundry treating apparatus according to the present disclosure.

FIG. 7 is a schematic diagram of flow of gaseous carbon dioxide that exchanges heat with a refrigerant from a distillation tank to a storage tank during the distillation operation.

FIG. 8 is a schematic diagram of a recovery operation of recovering gaseous carbon dioxide remaining in a pressure vessel after a distillation operation.

FIG. 9 is a schematic diagram of a recovery discharge operation of flowing carbon dioxide stored in a recovery tank to a storage tank after a recovery operation.

FIG. 10 is a flowchart briefly showing a washing cycle proceeding in a laundry treating apparatus according to the present disclosure.

Hereinafter, a preferred embodiment of the present disclosure will be described in detail with reference to the accompanying drawings. In one example, a configuration of a device or a method for controlling the same to be described below is only for describing an embodiment of the present disclosure, not for limiting the scope of the present disclosure, and reference numerals used the same throughout the specification refer to the same components.

Specific terms used in this specification are only for convenience of description and are not used as a limitation of the illustrated embodiment.

For example, expressions indicating that things are in the same state, such as "same", "equal", "homogeneous", and the like, not only indicate strictly the same state, but also indicate a state in which a tolerance or a difference in a degree to which the same function is obtained exists.

For example, expressions indicating a relative or absolute arrangement such as “in a certain direction”, “along a certain direction”, “parallel”, “orthogonal”, “central”, “concentric”, “coaxial”, or the like not only strictly indicate such arrangement, but also indicate a state in which a relative displacement is achieved with a tolerance, or an angle or a distance that achieves the same function.

In order to describe the present disclosure, the description below will be achieved on the basis of a spatial orthogonal coordinate system with an X-axis, a Y-axis, and a Z-axis orthogonal to each other. Each axial direction (an X-axis direction, a Y-axis direction, or a Z-axis direction) means both directions in which each axis extends. Adding a '+' sign in front of each axial direction (a +X-axis direction, a +Y-axis direction, or a +Z-axis direction) means a positive direction, which is one of the two directions in which each axis extends. Adding a '-' sign in front of each axial direction (a -X-axis direction, a -Y-axis direction, or a -Z-axis direction) means a negative direction, which is the other of the two directions in which each axis extends.

Expressions referring to directions such as “front (+Y)/rear (-Y)/left (+X)/right (-X)/up (+Z)/down (-Z)” to be mentioned below are defined based on a XYZ coordinate axis. However, this is to describe the present disclosure such that the present disclosure may be clearly understood. In one example, each direction may be defined differently depending on the standard.

The use of terms such as 'first, second, third' in front of the components to be mentioned below is only to avoid confusion of the components referred to, and is independent of the order, importance, or master-slave relationship between the components. For example, an invention including only the second component without the first component may also be implemented.

The singular expression includes the plural expression unless the context clearly dictates otherwise.

Hereinafter, the present disclosure is described on the premise that carbon dioxide is used as a washing solvent, but other washing solvents other than the carbon dioxide may be used.

(a) and (b) in FIG. 1 show a laundry treating apparatus 1000 as an example of the present disclosure. Referring to (a) in FIG. 1, the laundry treating apparatus 1000 includes a pressure vessel (or a washing chamber) 200 for maintaining the carbon dioxide contained therein at a pressure higher than an atmospheric pressure, a storage tank 150 that is located above the pressure vessel 200 and stores the carbon dioxide and supplies the carbon dioxide to the pressure vessel 200, and a distiller 400 disposed below the pressure vessel 200 and vaporizing liquid carbon dioxide of the carbon dioxide discharged from the pressure vessel 200 to remove foreign substances therefrom, and then, liquefying the vaporized carbon dioxide and supplying the liquid carbon dioxide to the storage tank 150.

The storage tank 150 being located above the pressure vessel 200 may mean that, when viewed from the front, a vertical height from a bottom surface to a center of a circular cross-section of the storage tank 150 having a cylindrical shape is greater than a vertical height to a center of a circular cross-section of the pressure vessel 200 having a cylindrical shape. This may be interpreted similarly to a distillation tank of the distiller 400, so that a distillation tank 401 may be located below the pressure vessel 200.

That is, a vertical level at which the storage tank 150 is installed may be higher than that of the pressure vessel 200, and a vertical level at which the distillation tank 401 is installed may be lower than that of the pressure vessel 200.

In addition, the laundry treating apparatus 1000 may include a cabinet 100 forming an appearance of the laundry treating apparatus 1000. The pressure vessel 200 may include a drum 300 rotatably disposed inside the pressure vessel 200 and accommodating laundry therein, and a driver 500 for rotating the drum 300.

In addition, the laundry treating apparatus 1000 may further include a frame 110 disposed inside the cabinet 100 for supporting the cabinet and supporting the pressure vessel, the storage tank 150, and the distiller 400.

The laundry treating apparatus 1000 may perform a washing cycle of, after supplying the carbon dioxide to the pressure vessel 200 from the storage tank 150 in response to an input of a user, removing the foreign substances from the laundry using friction between the laundry accommodated in the drum 300 and the liquid carbon dioxide by rotating the drum 300.

The washing cycle refers to a series of operations performed by the laundry treating apparatus 1000 when the user selects a course for washing of the laundry. The washing cycle may include a pressurization operation and a supply operation of supplying the carbon dioxide to the pressure vessel 200 from the storage tank 150, a washing operation of removing the foreign substances from the laundry using the friction between the liquid carbon dioxide and the laundry by rotating the drum 300 at a preset first rotation speed, and a rinsing operation of removing the foreign substances from the laundry using the friction between the liquid carbon dioxide and the laundry by rotating the drum 300 at a preset second rotation speed.

The rinsing operation may be repeated twice. Preferably, inside the pressure vessel (or washing chamber) 200, under conditions of approximately 45 to 51 bar and 10 to 15 ℃, the washing operation may be performed for 10 to 15 minutes and the rinsing operation may be performed for 3 to 4 minutes.

After the washing operation and the rinsing operation are completed, a distillation operation may be included. The distillation refers to heating a specific liquid mixed with the foreign substances (or pollutants), then vaporizing (or evaporating) only the specific liquid, and then cooling the specific liquid again to separate only a specific pure liquid. In this specification, the distillation refers to an operation of vaporizing the liquid carbon dioxide mixed with the foreign substances removed from the laundry and then cooling the vaporized carbon dioxide to separate only pure liquid carbon dioxide. The separated liquid carbon dioxide may be reused in a next operation after being supplied to the storage tank again.

The cabinet 100 may include a cabinet bottom surface (not shown) that forms a bottom surface of the laundry treating apparatus 1000, a top panel (not shown) that forms a top surface of the cabinet 100, a front panel 103 that forms a front surface of the cabinet 100 and connects the cabinet bottom surface and the top panel to each other, side panels (not shown) that form both side surfaces of the cabinet 100 and connect the cabinet bottom surface and the top panel to each other, and a rear panel (not shown) that forms a rear face of the cabinet.

The front panel 103 may have a cabinet inlet 1031 defined therein through which the laundry may be put into the drum 300 or the laundry accommodated in the drum 300 may be withdrawn to the outside of the cabinet 100. In addition, the laundry treating apparatus 1000 may include a door 130 pivotably disposed on the front panel 103 to open and close the cabinet inlet 1031.

The pressure vessel 200 may be located inside the cabinet 100 to accommodate the carbon dioxide therein. The pressure vessel 200 may include a vessel inlet 219 defined therein capable of being in communication with the cabinet inlet. When the door 130 is closed, not only the cabinet inlet 1031, but also the vessel inlet 219 is closed, so that the pressure vessel 200 may be a pressure vessel or a pressure-resistant vessel capable of accommodating high-pressure carbon dioxide therein.

For example, the carbon dioxide supplied to the pressure vessel 200 may maintain a predetermined pressure to exist as the liquid carbon dioxide. Preferably, the pressure may be a single pressure set in a pressure range from 45 bar to 51 bar.

The drum 300 may be rotatably disposed inside the pressure vessel 200. Specifically, the drum 300 may be rotatably disposed in an inner space of a first housing 211 (see FIG. 2), that is, in a first chamber 210. The drum 300 may include a plurality of side through-holes (not shown) defined in an inner circumferential surface of the drum 300 to allow fluid communication between the pressure vessel 200 and the drum 300. That is, the drum 300 may include a drum body 301 for accommodating the laundry therein, and the plurality of side through-holes (not shown) penetrating a side surface of the drum body.

Through the plurality of side through-holes, the carbon dioxide supplied to the pressure vessel 200, specifically to the first chamber 210 (see FIG. 2) may be introduced into an accommodation space, which is a space in which the laundry is accommodated inside the drum body, or may come out of the accommodation space into a space between the first chamber 210 (see FIG. 7) and the drum 300.

The drum 300 may have a cylindrical shape. Alternatively, the drum body 301 forming an appearance of the drum 300 may have a cylindrical shape.

Therefore, the pressure vessel may perform a role of the washing chamber in which the washing operation and the rinsing operation occur using the drum 300 disposed therein.

Referring to (a) and (b) in FIG. 1, the storage tank 150, the pressure vessel 200, and the distiller 400 may be located in an order of the vertical level in a height direction with respect to the bottom surface of the cabinet. This is to flow the liquid carbon dioxide by gravity even under the same pressure condition. That is, when the storage tank 150 and the pressure vessel 200 communicate with each other even when pressures thereof are the same, the gravity may flow the liquid carbon dioxide from the storage tank 150 to the pressure vessel 200. Similarly, even when pressures of the pressure vessel 200 and the distillation tank 401 of the distiller 400 are the same, the liquid carbon dioxide may be discharged from the pressure vessel 200 to the distillation tank 401 by the gravity based on a vertical level difference.

In addition, considering weights of the storage tank 150, the pressure vessel 200, and the distillation tank 401, and the size of the laundry treating apparatus, it may be preferable for the storage tank 150, the pressure vessel 200, and the distillation tank 401 to be disposed diagonally with respect to the height direction rather than disposed vertically in a straight line in the height direction in terms of weight distribution or miniaturization of the laundry treating apparatus.

Alternatively, as shown in (a) in FIG. 1, the distillation tank 401 and the storage tank 150 may be disposed closer to the other side surface than to one side surface of the cabinet 100.

Referring to (a) and (b) in FIG. 1, although it is shown that the storage tank 150 and the distillation tank 401 among the storage tank 150, the pressure vessel 200, and the distillation tank 401 are located closer to a right side of the cabinet than to a left side of the cabinet when viewed from the front, the storage tank 150 and the distillation tank 401 may be located on a side opposite thereto.

In an empty space remaining after the storage tank 150, the pressure vessel 200, and the distillation tank 401 are disposed,

various compressors

283 and 403, a controller 900, a heat dissipation fan 299, and various connection pipes may be located.

Referring to (b) in FIG. 1, the controller 900 may be located at a rear portion of the cabinet. This is for easy access to the controller 900. However, this is merely an embodiment. The controller 900 may be located on the side surface or the front surface of the cabinet. In FIG. 1, the controller 900 is formed in a shape of a box. A control device such as a programmable logic controller (PLC) may be disposed in the box. Alternatively, the controller 900 may be formed as a PCB including a microcomputer. FIG. 1 shows a state in which the box-like shape is pivotably disposed on the frame 110.

The controller may control the flow of the carbon dioxide by controlling opening and closing of each pipe through various flow rate control valves. In addition, the driver may be controlled to rotate the drum. In addition, the controller may receive the user input and perform the course or a cycle selected by the user based on a preset operation.

This is a result of considering maintenance because the pressure vessel 200 is exposed as the controller 900 is pivoted.

The heat dissipation fan 299 may be disposed to cool the compressors 283 and 403 (see FIG. 6) that compress the refrigerant or to maintain air inside the cabinet 100 at a constant temperature. FIG. 1 shows an example in which the heat dissipation fan is located at a rear lower portion of the cabinet, but the heat dissipation fan may be located anywhere as long as the heat dissipation fan is able to cool the

compressors

283 and 403 and maintain the air inside the cabinet 100 at the constant temperature. The

compressors

283 and 403 may be used to compress the gaseous carbon dioxide in the distillation operation. Alternatively, heat may be supplied to the pressure vessel 200 using the high-temperature gaseous carbon dioxide compressed in a recovery operation.

FIG. 2 shows the pressure vessel 200. The pressure vessel 200 may accommodate the carbon dioxide therein at the pressure higher than the atmospheric pressure. This is because the liquid carbon dioxide is required for the washing of the laundry, and the high pressure is essential for the same. The pressure vessel 200 may include the drum 300 and the driver 500 therein.

Specifically, the pressure vessel 200 may include the first housing 211 and a second housing 221 forming an appearance of the pressure vessel. The first housing 211 may form the first chamber 210 which is the space to which the drum 300 for accommodating the laundry is inserted.

The drum 300 may be constructed to be rotatable, so that the liquid carbon dioxide and the laundry will be mixed with each other in the state in which the laundry is accommodated inside the drum 300.

The first housing 211 may have a first opening 213 defined therein that is opened on a side opposite to the vessel inlet 219 defined in a front surface of the first housing 211, that is, a side coupled to the second housing. That is, the first opening 213 may be located on the opposite side of the vessel inlet 219, and may be larger than the vessel inlet 219.

The first housing 211 may be formed in a shape of a cylinder as a whole, and may have the vessel inlet 219 defined therein having a circular shape on one side thereof, and have the first opening 213 defined therein having a circular shape on the other side.

The drum 300 may be formed in a cylindrical shape similar to the shape of the first chamber 210, which is the inner space of the first housing 211. In addition, the drum 300 may rotate in a clockwise or counterclockwise direction inside the first housing 211.

The size of the first opening 213 may be larger than a size of a cross-section of the drum 300 such that an operator or the user may withdraw the drum 300 through the first opening 213 and repair the drum 300. In this connection, the size of the first opening 213 may be greater than a size of a maximum cross-section of the drum 300. Accordingly, the operator or the like may withdraw the drum 300 by opening the first opening 213 after separating the first housing 211 and the second housing 221 from each other. In addition, it is also possible to install the drum 300 inside the first housing 211 through the first opening 213.

The first housing 211 has an inflow pipe (not shown) through which the carbon dioxide is supplied from the storage tank 150 to the first housing 211. The inflow pipe, which is a pipe exposed to the outside of the first housing 211, may flow the carbon dioxide to the interior of the first housing 211, that is, to the first chamber 210 from the storage tank 150.

The first housing 211 may include a filter assembly 350 filtering large foreign substances that do not dissolve in the liquid carbon dioxide when the liquid carbon dioxide used in the first chamber 210 flows to the distiller 400. The filter 350 may be disposed on a lower outer circumferential surface of the first housing 211. The filter 350 may include a filter insertion portion 351 formed to protrude from the cylindrical shape of the first housing 211 in a radial direction to define a space into which a filter may be inserted, and a discharge hole defined through the filter insertion part 351 to discharge the liquid carbon dioxide that has passed through the filter to the distillation tank 401.

The first housing 211 and the distillation tank 401, specifically, the discharge hole 352 and the distillation tank 401 may be connected to each other through a discharge pipe 630 (see FIG. 6).

The first housing 211 may include a first flange 212 formed along the first opening 213. The first flange 212 may extend in the radial direction along the outer circumferential surface of the first housing 211 similarly to the cylindrical shape of the first housing 211. The first flange 212 is disposed evenly along a circumference of the first housing 211 in a direction in which a radius of the first housing 211 increases.

Referring to FIG. 2, the second housing 221 may be coupled to the first housing 211 to form one pressure vessel 200. In this connection, the interior of the pressure vessel 200 may be divided into the first chamber 210, which is a space in which laundry treatment is performed, and a second chamber 220, which is a space in which the driver 500 providing a driving force for rotating the drum is installed, by a separator 250. However, this is merely one example, and the interior of the pressure vessel 200 may be defined as a single space without being divided by the separator 250.

Schematically, the separator 250 may be coupled to the first opening 213 in a disk shape. Therefore, the first chamber 210 of an inner space of the pressure vessel 200 may be formed by the first housing 211 and the separator 250, and the second chamber 220 may be formed by the second housing 221 and the separator 250. The drum 300 may be accommodated in the first chamber 210, and the driver 500 may be accommodated in the second chamber 220. Accordingly, a through-hole for connecting a rotation shaft (not shown) disposed in the driver 500 to the drum 300 may be defined at a center of the separator 250.

The second housing 221 may include a second flange 222 coupled to the first flange 212. The second housing 221 may be formed to have a size similar to that of the cross-section of the first housing 211 to be disposed at the rear of the first housing 211.

The second flange 222 may be coupled to the first flange 212 by a plurality of fastening members, for example, bolts and nuts, to allow an internal pressure to be maintained to be higher than an external atmospheric pressure in a state in which the second housing 221 is fixed to the first housing 211.

The filter capable of filtering the foreign substances is disposed in the filter insertion portion 351 formed in the first housing 211. The filter includes a plurality of small holes, so that, while the foreign substances are not able to pass through the holes, the liquid carbon dioxide may pass through the holes and be discharged to the outside of the first housing 211 through the discharge pipe 630. For example, the filter may be formed in a shape of a mesh.

FIG. 2 shows a state in which the partition wall 251 is coupled to the first housing 211, but the separator 250 may be coupled to the second housing 221.

The separator 250 may block the flow of the liquid carbon dioxide of the carbon dioxide stored in the first chamber 210 to the second chamber 220. On the other hand, the gaseous carbon dioxide of the carbon dioxide stored in the first chamber 210 may flow through the separator 250 freely. This is to reduce a stress on the partition wall by balancing a pressure between the first chamber 210 and the second chamber 220.

That is, when the high-pressure carbon dioxide is accommodated in the first chamber 210 and the second chamber is maintained at the atmospheric pressure, or the pressure of the first chamber 210 is reduced from the high pressure to the atmospheric pressure or increased from the atmospheric pressure to the high pressure, the partition wall 251 may be stressed by a pressure difference, which may cause destruction due to fatigue or deformation due to stress of the partition wall 251. To prevent this, the partition wall 251 allows the gaseous carbon dioxide to flow freely but does not allow the liquid carbon dioxide to flow freely to prevent the liquid carbon dioxide from being filled in an unnecessary portion and being wasted while maintaining the pressure difference.

To this end, a graphite gasket (not shown) may be disposed between the partition wall 251 and a seating groove 2122 to which the partition wall is coupled. In addition, all through-holes defined in the partition wall, which will be described later, may be sealed except for a second through-hole. This is to prevent the flow of the liquid carbon dioxide while allowing the gaseous carbon dioxide to flow freely through the second through-hole 2512 (see FIG. 3).

At least one second through-hole 2512 may be defined at an upper end of the partition wall where the liquid carbon dioxide does not reach. Therefore, the flow of the gaseous carbon dioxide is possible, so that it is possible to maintain the pressure equalization between the left and right spaces. After all, because there is no pressure difference between the first chamber 210 and the second chamber 220, the graphite gasket does not need to block the flow of the liquid carbon dioxide resulted from the pressure and simply blocks the flow by gravity, so that an excessive fastening force may not be required for the graphite gasket.

However, this is merely one embodiment. The liquid carbon dioxide may be accommodated in the pressure vessel without the separator 250 or the partition wall 251, that is, without the distinction between the first chamber 210 and the second chamber 220. In this case, the driver 500 and the drum 300 will be disposed in the same space without the distinction of the chamber by the partition wall.

Based on FIG. 2, in the space on the left side of the partition wall 251, in the first chamber 210, the drum 300 is disposed, so that the laundry and the liquid carbon dioxide may be mixed with each other to perform the laundry treatment such as the washing operation, the rinsing operation, or the like. On the other hand, in the space on the right side of the partition wall 251, the driver 500 may be disposed to provide the driving force for rotating the drum 300. In this connection, a portion of the driver 500 may penetrate the partition wall 251 to be coupled to the drum 300.

The partition wall 251 may be formed to be larger than the first opening 213 and may be disposed to be in contact with the first opening 213 to seal the first opening 213. The partition wall 251 and the first opening 213 are formed in an approximately circular shape similar to the shape of the first housing 211. A diameter L of the first opening 213 is smaller than a diameter of the partition wall 251. The diameter L of the first opening 213 is larger than a diameter of the drum 300. Accordingly, the size of the cross-section of the drum 300 is the smallest, a cross-section of the first opening 213 has a middle size, and the size of the partition wall 251 is the largest.

The partition wall 251 is constructed to have a plurality of steps, so that strength may be secured.

The seating groove 2122 to which the partition wall 251 is coupled may be defined in the first flange 212 along the first opening 213. That is, the seating groove 2122 may be defined at a portion extended in the radial direction from the first opening 213. The seating groove 2122 may be recessed by a depth equal to greater than a thickness of the partition wall 251, so that the first flange 212 and the second flange 222 may be in contact with each other. When the seating groove 2122 is defined to be recessed by the thickness of the partition wall 251 and to have a shape corresponding to a shape of an outer circumferential surface of the partition wall 251, it may be possible to flatten a surface of the first flange 212 when the partition wall 251 is seated in the seating groove 2122.

A first seating surface 2124 extending in the radial direction further than a circumference of the seating groove 2122 is disposed in the first flange 212, and a second seating surface (not shown) in surface contact with and coupled to the first seating surface 2124 is disposed in the second flange 222. The first seating surface 2124 and the second seating surface are disposed to be in contact with each other, so that the carbon dioxide injected into the inner space of the first housing 211 is prevented from being discharged to the outside. The first seating surface 2124 and the second seating surface may be respectively disposed on outer circumferential surfaces of the first housing 211 and the second housing 221 to provide a coupling surface where the two housings may be coupled to each other by a fastening member while being in surface contact with each other.

When the partition wall 251 is separated from the first housing 211, the first opening 213 will be exposed. In this connection, the drum 300 may be withdrawn to the outside through the first opening 213. Because the size of the first opening 213 is larger than the size of the drum 300, maintenance of the drum 300 is possible through the first opening 213.

A gasket (not shown) is disposed between the partition wall 251 and the seating groove 2122. Accordingly, when the partition wall 251 is coupled to the first housing 211, it is possible to prevent the carbon dioxide from leaking to the space between the partition wall 251 and the seating groove 2122. When the partition wall 251 is seated in the seating groove 2122, the partition wall 251 may be coupled to the seating groove 2122 by a plurality of fastening members while pressing the gasket. The plurality of third through-holes 2513 (see FIG. 3) for coupling to the first housing 211 may be evenly defined in the partition wall 251 along an outer circumferential surface of the partition wall 251.

In addition, the partition wall 251 may be coupled to the driver 500 to support the driver 500. Because the rotation shaft of the driver 500 passes through the separator 250 and is connected to the drum 300, the partition wall may eventually serve to support both the drum 300 and the driver 500.

(a) and (b) in FIG. 3 are views of the partition wall 251 viewed from the front and the side, respectively.

Referring to (a) in FIG. 3, the first through-hole 2511 through which the rotation shaft of the driver 500 passes to be coupled with the drum 300 may be defined at the center of the partition wall 251. The first through-hole 2511 may have a circular shape, so that interference thereof with the rotation shaft passing through the first through-hole 2511 may be prevented.

In addition, the partition wall 251 may further include the at least one second through-hole 2512 for allowing the gaseous carbon dioxide to freely flow between the first chamber 210 and the second chamber 220. The at least one second through-hole 2512 may be defined at a higher position than the first through-hole 2511. A maximum liquid level of the liquid carbon dioxide is lower than a vertical level at which the at least one second through-hole 2512 is located with respect to the bottom surface, so that the liquid carbon dioxide may be prevented from flowing through the at least one second through-hole 2512.

Normally, an amount of liquid carbon dioxide used in the washing operation or the rinsing operation does not exceed half of the drum 300. That is, the liquid carbon dioxide does not flow up to a vertical level equal to or higher than a vertical level of the rotation shaft of the driver 500 coupled to the drum 300, that is, a minimum vertical level of the first through-hole with respect to the bottom surface (a vertical level of a center of the first through-hole - a radius of the first through-hole).

Therefore, when the second through-hole 2512 is located at the higher position than the first through-hole 2511, no liquid carbon dioxide will flow through the second through-hole 2512. On the other hand, because the gaseous carbon dioxide is filled in the space defined by the first housing 211 and the partition wall 251, the gaseous carbon dioxide may freely flow into the space defined by the second housing 221 and the partition wall 251 to achieve the pressure equalization.

That is, while the laundry treatment such as the washing operation or the rinsing operation is performed, in the space partitioned by the first housing 211 and the partition wall 251, the gaseous carbon dioxide and the liquid carbon dioxide are mixed. On the other hand, in the space partitioned by the second housing 221 and the partition wall 251, the liquid carbon dioxide does not exist and only the gaseous carbon dioxide exists. Because the two spaces are in the state of pressure equilibrium, the liquid carbon dioxide may not need to exist in the space defined by the second housing 221 and the partition wall 251, and an amount of liquid carbon dioxide used may be reduced.

Therefore, the total amount of carbon dioxide used for the washing operation, the rinsing operation, or the like may be reduced, so that the amount of carbon dioxide used is reduced compared to that in the prior art. This will reduce an amount of carbon dioxide that has to be reprocessed after the use.

As the amount of carbon dioxide used is reduced, a capacity of the tank for storing the carbon dioxide may be reduced, as well as an overall size of the washing machine for using the carbon dioxide. In addition, because an amount of carbon dioxide that has to be distilled after the use is reduced, a time it takes for the washing cycle may be reduced.

In addition, when the partition wall 251 is separated from the first housing 211, it is possible to provide an environment in which the user or the like may separate the drum 300 from the first housing 211.

The partition wall 251 may be stepped forwardly or rearwardly a plurality of times, and strength thereof may be increased. In addition, the partition wall 251 may have a curved surface in some sections, so that the partition wall 251 may be formed to withstand forces in various directions.

An outermost portion of the partition wall 251 may have a shape coupled to the seating groove 2122 of the first housing 211. In addition, the partition wall 251 may include the plurality of third through-holes 2513 in a portion corresponding to the seating groove 2122 to be coupled to the first housing 211 using the fastening member after being coupled to the seating groove 2122.

Based on (b) in FIG. 3, in a direction from the outermost portion of the partition wall 251 to a central portion, the partition wall 251 may be stepped by various lengths in various directions, such as protruding leftwards, then protruding rightwards, and then protruding leftwards again, so that the strength may be increased.

FIG. 4 shows an example of components of a conventional laundry treating apparatus using carbon dioxide as a washing solvent. Referring to FIG. 4, the laundry treating apparatus using the carbon dioxide as the washing solvent may include the pressure vessel 200 that accommodates the laundry therein and performs the washing and the rinsing using the supplied carbon dioxide, the storage tank 150 that stores the used carbon dioxide after the distillation and supplies the carbon dioxide to the pressure vessel (or the washing chamber) 200, and the distiller 40 that distills the carbon dioxide emitted after the use.

The pressure vessel 200 may further include the filter assembly 350 for removing the foreign substances insoluble in the liquid carbon dioxide discharged after the use. As described above, the filter assembly 350 may be disposed on the lower surface of the pressure vessel 200. However, for description, the present drawing illustrates an example in which the filter assembly 350 is independently disposed between the pressure vessel 200 and the distiller 40.

In addition, the laundry treating apparatus 1000 may further include a replenishment tank 155 for replenishing the carbon dioxide lacking in the pressure vessel 200.

The distiller 40 is to remove the foreign substances from the carbon dioxide used in the washing operation and the rinsing operation, that is, the carbon dioxide used in the pressure vessel, and then distill the carbon dioxide for the reuse. As described above, in order to remove the foreign substances from the liquid carbon dioxide, particularly foreign substances dissolved in the liquid carbon dioxide, only the liquid carbon dioxide should be vaporized and then cooled again.

To this end, the conventional distiller 40 may include the distillation tank 401 for storing the carbon dioxide discharged from the pressure vessel, the CO2 compressor 290 located outside the distillation tank 401 and sucking and compressing the gaseous carbon dioxide from the distillation tank 401, and a heat exchanger 42 located inside the distillation tank 401 and connected to the CO2 compressor 290 to exchange the heat of the compressed gaseous carbon dioxide with the liquid carbon dioxide stored inside the distillation tank 401.

The conventional distiller 40 may further include a cooler 160 for liquefying the distilled carbon dioxide.

FIG. 4 schematically shows each component, so that the plurality of valves or the controller is omitted, and the plurality of pipes are indicated by lines. In addition, a flow direction of the carbon dioxide is indicated by an arrow.

A triple point of the carbon dioxide (CO2) is known to be 5.1 atm and -56.6 ℃. Therefore, a phase change from a solid (dry ice) to a gas occurs when the temperature is changed under a pressure lower than the triple point, whereas, under a pressure higher than the triple point, the carbon dioxide exists as a liquid and a gas, so that a phase change between a liquid and a gas may occur depending on given pressure and temperature.

Therefore, when the carbon dioxide is pressurized, like using water as the washing solvent in a general laundry treating apparatus, the liquid carbon dioxide (CO2(L) or L-CO2) may be used as the washing solvent. However, in a case of a water-soluble substance, washing power using the carbon dioxide is low, so that a detergent or a surfactant may be additionally used to remove water-soluble substances.

A fluid other than the carbon dioxide may be used as the washing solvent. The fluid may be a fluid whose phase change from a gas to a liquid occurs or that may be in a state of supercritical fluid when pressurized at a predetermined temperature.

When the carbon dioxide is used as the washing solvent, all of the carbon dioxide evaporates into gas when a pressure thereof is reduced to the atmospheric pressure after the washing cycle is completed. Therefore, there is no need to go through a separate drying cycle that requires a long time, and there is no odor even when there is residual carbon dioxide. However, because the carbon dioxide is used by being pressurized, unlike a tub of the general laundry treating apparatus, a sealed pressure vessel is required to prevent the carbon dioxide from leaking.

Therefore, the pressure vessel 200 is an airtight container from which the pressurized carbon dioxide is not able to escape, and must be formed as a tank that may withstand the pressure of the pressurized carbon dioxide. This is also true for the storage tank 150, the replenishment tank 155, and the distillation tank 401.

When the distiller 40 is constructed like in the conventional laundry treating apparatus shown in FIG. 4, the CO2 compressor 290 requires a size larger than that in a case of using a general refrigerant compressor to meet a required compression ratio. Accordingly, it requires a large space inside the laundry treating apparatus. In addition, during the compression of the CO2 compressor 290, lubricating oil and impurities resulted from friction of a mechanical driver may be mixed into the gas carbon dioxide compressed in the CO2 compressor 290. This eventually degrades the washing performance. In addition, when a general gas other than the refrigerant is compressed at a high compression ratio, energy is wasted severely.

In order to solve the above-mentioned problem, the laundry treating apparatus 1000 described in the present disclosure uses a thermosiphon for the distillation. The thermosiphon, which uses a phenomenon of fluid flowing from a place of high pressure to a place of low pressure without additional mobilization, occurs in the present disclosure because high-temperature gaseous carbon dioxide naturally flows from the distillation tank 401 to the storage tank 150, and the flowed high-temperature gaseous carbon dioxide is liquefied in the storage tank 150.

The liquid carbon dioxide in which the foreign substances are dissolved as being used after the washing is vaporized and only pure gaseous carbon dioxide is produced. As liquefying the pure gaseous carbon dioxide again, the used carbon dioxide may be reused.

(a) to (c) in FIG. 5 are shown to describe the thermosiphon used in the present disclosure. Supply and release of heat are indicated by large arrows, and flow of the carbon dioxide is indicated by solid lines and small arrows. However, in order to simplify the flow of the carbon dioxide, a position of the CO2 compressor 290 is marked differently, and a circulation path for heat exchange in the distillation tank is also marked differently. (a) in FIG. 5 shows the flow of the heat and the flow of the carbon dioxide in the conventional laundry treating apparatus. The gaseous carbon dioxide sucked from the distillation tank 401 into the CO2 compressor 290 may become the gaseous carbon dioxide of the high temperature and high pressure. The gaseous carbon dioxide of the high temperature and high pressure may go back into the distillation tank 401, then exchange heat with the liquid carbon dioxide, and then be liquefied through the cooler 160. Thereafter, the liquefied carbon dioxide may be stored in the storage tank 150.

Therefore, the CO2 compressor 290 is required for the compression and the flow of the carbon dioxide. In the distillation tank 401, the carbon dioxide vaporized by receiving the heat transferred by the high-temperature and high-pressure gaseous carbon dioxide will release the heat through the cooler 160 and then be stored in the storage tank 150. That is, because the heat is supplied and then the heat is released as it is, a lot of energy may be consumed.

On the other hand, (b) in FIG. 5 shows that the carbon dioxide vaporized by naturally receiving the heat from the distillation tank 401 without the CO2 compressor 290 is flowed to the storage tank 150. The carbon dioxide will release the heat and be liquefied and stored in the storage tank 150. To this end, something is needed to supply the heat to the carbon dioxide stored in the distillation tank 401 and to take the heat away from the gaseous carbon dioxide in the storage tank 150. To this end, the refrigerant is circulated instead.

To circulate the refrigerant, the refrigerant compressor for compressing the refrigerant and the heat exchanger for exchanging heat with the carbon dioxide in the distillation tank 401 and the storage tank 150 will be required. The high-temperature and high-pressure refrigerant compressed by the refrigerant compressor will supply the heat to the distillation tank 401, and the refrigerant cooled while circulating will take the heat away from the storage tank 150.

Energy use may be reduced using a refrigerant compressor with smaller capacity and size compared to the CO2 compressor 290 that compresses the carbon dioxide. It is possible to prevent the carbon dioxide and the refrigerant from mixing with each other, and prevent the carbon dioxide and the oil or the foreign substances of the refrigerant compressor from meeting each other. In other words, only the carbon dioxide will always flow in the pipe where the carbon dioxide flows.

(c) in FIG. 5 shows a case in which the laundry treating apparatus 1000 described in the present disclosure further includes a recovery assembly 280 for recovering gaseous carbon dioxide remaining in the pressure vessel (or the washing chamber) 200 after the distillation operation. When using the thermosiphon as in (b) in FIG. 5, the existing laundry treating apparatus may use the CO2 compressor 290 also in recovery operation. However, because there is no CO2 compressor 290 in the laundry treating apparatus 1000 described in the present disclosure, a separate component is required to recover the gas remaining in the pressure vessel after the distillation operation.

The recovery assembly 280 may also liquefy the gaseous carbon dioxide using the refrigerant that exchanges heat with the gaseous carbon dioxide.

As the compressor for compressing the refrigerant, a distillation compressor 403 for the distillation and a recovery compressor 283 for the recovery may be independently disposed.

FIG. 6 is a schematic diagram of circulation of the refrigerant between the distillation tank 401 and the storage tank 150 during the distillation operation proceeding in the laundry treating apparatus according to the present disclosure. FIG. 7 is a schematic diagram of flow of the gaseous carbon dioxide that exchanges heat with the refrigerant from the distillation tank 401 to the storage tank 150 during the distillation operation. Therefore, although FIGS. 6 and 7 are separated for convenience of description, the circulation of the refrigerant and the vaporization, the flow, and the liquefaction of the carbon dioxide will occur simultaneously in the distillation operation.

Referring to FIG. 6, the circulation path of the refrigerant for distilling the carbon dioxide used in the washing and rinsing operations and mixed with the foreign substances is shown. That is, FIG. 6 shows the circulation path of the refrigerant in the distillation operation of distilling the liquid carbon dioxide discharged from the pressure vessel 200 to the distillation tank 401.

While the distiller disposed in the conventional laundry treating apparatus compresses the carbon dioxide and exchanges heat using the compressed carbon dioxide, the laundry treating apparatus 1000 according to the present disclosure includes the pressure vessel 200 that maintains the carbon dioxide contained therein at the pressure higher than the atmospheric pressure, the storage tank 150 that stores the carbon dioxide to supply the carbon dioxide to the pressure vessel 200, and the distillation tank 401 that stores the carbon dioxide discharged from the pressure vessel 200 to remove the foreign substances dissolved in the carbon dioxide discharged from the pressure vessel 200.

In addition, in order to take advantage of the thermosiphon phenomenon, the laundry treating apparatus 1000 may further include a distillation heat exchanger 402 located inside the distillation tank 401 to exchange heat with the carbon dioxide stored in the distillation tank 401, a storage heat exchanger 152 located inside the storage tank 150 to exchange heat with the carbon dioxide stored in the storage tank 150, the distillation compressor 403 for compressing the refrigerant circulating in the distillation heat exchanger 402 and the storage heat exchanger 152, and a distillation refrigerant flow path 660 that connects the distillation heat exchanger 402, the storage heat exchanger 152, and the distillation compressor 403 to each other to form a flow path in which the refrigerant circulates.

In addition, the laundry treating apparatus 1000 may further include a distillation expander 406 that expands the refrigerant that has passed through the distillation heat exchanger on the distillation refrigerant flow path. The distillation expander 406 may cool the refrigerant through a throttling process. The distillation expander 406 may be in a form of a capillary-shaped pipe curved into a circle. Alternatively, the distillation expander 406 may be an electronic expansion valve (EEV) for adjusting the flow rate of the refrigerant.

In addition, the laundry treating apparatus 1000 may further include a storage pipe 610 that connects the distillation tank 401 and the storage tank 150 to each other to flow the gaseous carbon dioxide stored in the distillation tank 401 to the storage tank 150. Therefore, after flowing the carbon dioxide vaporized in the distillation tank 401 through the storage pipe 610, the carbon dioxide will be liquefied in the storage tank 150 and the liquid carbon dioxide will be stored.

When the gaseous carbon dioxide flows from the distillation tank 401 to the storage tank 150, a separate driving source is not required. This is because, when the temperature inside the distillation tank 401 rises through the heat exchange with the refrigerant, the internal pressure of the distillation tank 401 becomes higher than the internal pressure of the storage tank 150. Accordingly, the gaseous carbon dioxide will naturally flow from the distillation tank 401 to the storage tank 150. In addition, because the gaseous carbon dioxide is liquefied through the heat exchange with the refrigerant in the storage tank 150, the pressure of the storage tank 150 will be lowered. In addition, as the liquid carbon dioxide vaporizes in the distillation tank 401, the liquid level will be lowered, which will overheat the vaporized gaseous carbon dioxide and further increase the internal pressure of the distillation tank.

Therefore, when the internal pressure of the distillation tank 401 becomes higher than a preset danger pressure, the controller 900 may stop the operation of the distillation compressor 403. Preferably, the danger pressure may be set to 50 bar.

Between the distillation tank 401 and the storage tank 150, the refrigerant will circulate along the distillation refrigerant flow path 660. The distillation refrigerant flow path 660 may include a first circulation pipe 661 for connecting the distillation compressor 403 and the distillation heat exchanger 402 to each other to flow the refrigerant compressed in the distillation compressor 403 to the distillation heat exchanger 402, a second circulation pipe 662 for connecting the distillation heat exchanger 402 and the distillation expander 406 to each other to flow the refrigerant that has exchanged heat with the carbon dioxide stored in the distillation tank 401 from the distillation heat exchanger 402 to the distillation expander 406, a third circulation pipe 663 for connecting the distillation expander 406 and the storage heat exchanger 152 to each other to flow the refrigerant cooled through the distillation expander 406 to the storage heat exchanger 152, and a fourth circulation pipe 664 for connecting the storage heat exchanger 152 and the distillation compressor 403 to each other to flow the refrigerant that has exchanged heat with the carbon dioxide stored in the storage tank 150 from the storage heat exchanger 152 to the distillation compressor 403.

That is, it is possible to reduce the size of the compressor using the distillation compressor 403 that compresses the refrigerant instead of using the separate CO2 compressor 290. In addition, there will be no mixing of the oil or the impurities and the carbon dioxide in the compressor by differentiating the flow paths of the refrigerant and the carbon dioxide.

The refrigerant may be a refrigerant used in a conventional heat pump or refrigerator. For example, the refrigerant may be Freon gas, R-134a, or R-290.

A refrigerant of a relatively high temperature and high pressure will pass through the first circulation pipe 661 and the second circulation pipe 662 through which the refrigerant that has passed through the distillation compressor 403 passes, and a refrigerant of a relatively low temperature and low pressure will pass through the third circulation pipe 663 and the fourth circulation pipe 664 through which the refrigerant that has passed through the distillation expander 406 passes.

Therefore, a temperature of the refrigerant passing through the second circulation pipe 662 will be higher than a temperature of the refrigerant passing through the third circulation pipe 663. In addition, a temperature of the refrigerant passing through the distillation heat exchanger 402 will be higher than a temperature of the refrigerant passing through the storage heat exchanger 152.

In addition, in the distillation process, a temperature of the refrigerant passing through the distillation heat exchanger 402 will be higher than a temperature of the carbon dioxide stored in the distillation tank 401, and a temperature of the refrigerant passing through the storage heat exchanger 152 will be maintained higher than a temperature of the gaseous carbon dioxide stored in the storage tank 150.

Therefore, the vaporization and the liquefaction of the carbon dioxide occur due to the heat exchange with the refrigerant. Eventually, the gaseous carbon dioxide will naturally flow from the distillation tank 401 to the storage tank 150 by the thermosiphon phenomenon.

Preferably, the distillation heat exchanger 402 may be located inside the distillation tank 401 at a lower portion thereof, and the storage heat exchanger 152 may be located inside the storage tank 150 at an upper portion thereof. This is because a purpose of the distillation heat exchanger 402 is to vaporize the liquid carbon dioxide, whereas a purpose of the storage heat exchanger 152 is to liquefy the gaseous carbon dioxide.

FIG. 7 is a schematic diagram of the flow of the gaseous carbon dioxide that exchanges heat with the refrigerant from the distillation tank 401 to the storage tank 150 during the distillation operation.

As the refrigerant circulates between the distillation tank 401 and the storage tank 150, the heat will be released in the distillation tank 401 and the heat will be absorbed in the storage tank 150 through the distillation heat exchanger 402 and the storage heat exchanger 152. Accordingly, the liquid carbon dioxide stored in the distillation tank 401 will be vaporized, and the gaseous carbon dioxide stored in the storage tank 150 will be liquefied.

To this end, the laundry treating apparatus 1000 may further include the storage pipe 610 for connecting the distillation tank 401 and the storage tank 150 to each other to flow the gaseous carbon dioxide stored in the distillation tank 401 to the storage tank 150. In addition, a storage control valve 615 for opening and closing the storage pipe 610 may be further included on the storage pipe 610. In the distillation operation, the controller 900 will not only circulate the refrigerant by operating the distillation compressor 403, but also open the storage control valve 615 to flow the gaseous carbon dioxide from the distillation tank 401 to the storage tank 150.

Preferably, the storage pipe 610 may connect a top of the distillation tank 401 and a top of the storage tank 150 to each other. This is because, in the distillation tank 401, the gas must be flowed. In addition, this is because, when a bottom of the storage tank 150 is connected, heat may be transferred to the stored liquid carbon dioxide unnecessarily and the liquid carbon dioxide may be vaporized. It is also to maintain a stable liquid carbon dioxide liquid level.

In FIG. 7, the storage pipe 610 may be combined with a first supply pipe 621 that is used when supplying the gaseous carbon dioxide from the storage tank 150 to the pressure vessel 200 at a point A. Thereafter, an example in which the storage pipe 610 and the first supply pipe 621 are connected to the pressure vessel 200 through a shared pipe 680 is shown. However, this is merely an example. As long as the vaporized gaseous carbon dioxide is finally able to flow from the distillation tank 401 to the storage tank 150, the storage pipe may be connected in another way.

Referring to FIG. 7, a first supply control valve 625 for opening the first supply pipe 621 may be positioned on the first supply pipe 621. Accordingly, the controller 900 may open the storage control valve 615 and the first supply control valve 625 to flow the gaseous carbon dioxide from the distillation tank 401 to the storage tank 150 through the storage pipe 610. Other valves, such as a shared pipe control valve 6801, will be closed.

Alternatively, the storage pipe 610 may directly connect the distillation tank 401 and the storage tank 150 to each other to flow the gaseous carbon dioxide from the distillation tank 401 to the storage tank 150. As described with reference to FIGS. 6 and 7, the laundry treating apparatus 1000 according to the present disclosure may prevent the oil or the other impurities from entering the carbon dioxide because the circulation path of the refrigerant and the flow path of the carbon dioxide are separated from each other.

FIG. 8 shows a recovery operation for recovering the gaseous carbon dioxide remaining in the pressure vessel 200 before the completion of the washing cycle after the distillation operation is completed.

The recovery operation refers to an operation of recovering the gaseous carbon dioxide remaining in the pressure vessel 200 before terminating the washing cycle. This is because there is still a significant amount of gaseous carbon dioxide remaining in the pressure vessel 200 although all of the liquid carbon dioxide has been discharged from the pressure vessel 200 and has undergone the distillation operation.

To this end, the laundry treating apparatus 1000 may further include the recovery assembly 280 positioned outside the pressure vessel 200 to circulate and liquefy the gaseous carbon dioxide stored in the pressure vessel 200. The recovery assembly 280 may include a recovery flow path 284 located outside the pressure vessel 200 and circulating the gaseous carbon dioxide of the pressure vessel 200, and a recovery heat exchanger 281 located on the recovery flow path 284 and liquefying the gaseous carbon dioxide by exchanging heat with the gaseous carbon dioxide passing through the recovery flow path 284.

Accordingly, in the laundry treating apparatus 1000 according to the present disclosure, a recovery cycle for recovering the gaseous carbon dioxide and a distillation cycle for the distillation for removing the foreign substances from the carbon dioxide may be separated from each other.

The recovery heat exchanger 281 may include a first heat exchanger 2811 serving as an evaporator, and a second heat exchanger 2812 serving as a condenser. The first heat exchanger 2811 and the second heat exchanger 2812 may be a fin tube heat exchanger having thermally conductive fins in the radial direction of the pipe.

In addition, the laundry treating apparatus 1000 may further include a recovery body 2843 positioned on the recovery flow path 284 to accommodate the recovery heat exchanger 281 therein and store the carbon dioxide liquefied through the recovery heat exchanger 281.

In addition, a recovery compressor 283 that compresses and circulates the refrigerant to exchange heat with the gaseous carbon dioxide through the recovery heat exchanger 281, and a recovery fan 285 positioned on the recovery flow path 284 to circulate the gaseous carbon dioxide of the pressure vessel 200 may be further included.

The recovery compressor 283 may be located outside the recovery body 2843. The recovery fan 285 may be positioned to meet the gaseous carbon dioxide inside the recovery body 2843 after the gaseous carbon dioxide passes through the recovery heat exchanger 281, or may be positioned to meet the gaseous carbon dioxide before the gaseous carbon dioxide passes through the recovery heat exchanger 281.

In addition, a recovery refrigerant flow path 2831 that circulates the refrigerant compressed in the recovery compressor 283, and a recovery expander 286 disposed outside the recovery body to expand the refrigerant through a throttling process may be further included. The recovery expander 286 may be a capillary tube-shaped pipe or an electronic expansion valve.

Through the recovery refrigerant flow path 2831, the refrigerant cooled in the recovery expander 286 may pass through the first heat exchanger 2811 and exchange heat with the gaseous carbon dioxide passing through the first heat exchanger 2811 to liquefy the gaseous carbon dioxide. In addition, the refrigerant that has passed through the first heat exchanger 2811 will be compressed through the recovery compressor 283. The refrigerant that has passed through the recovery compressor 283 will exchange heat with the gaseous carbon dioxide passing through the second heat exchanger 2812, thereby transferring heat to the gaseous carbon dioxide.

The recovery fan 285 may suck the gaseous carbon dioxide from the pressure vessel 200 and circulate the gaseous carbon dioxide back to the pressure vessel 200 through the recovery body 2843.

The recovery flow path 284 may include a recovery suction pipe 2841 for introducing the gaseous carbon dioxide from the pressure vessel 200 to the recovery body 2843, and a recovery discharge pipe 2842 for discharging the gaseous carbon dioxide from the recovery body 2843 to the pressure vessel 200.

The recovery body 2843 may be formed in a shape of a duct, and may include the first heat exchanger 2811 and he second heat exchanger 2812 therein. The recovery fan 285 may also be disposed inside the recovery body 2843. In addition, the carbon dioxide liquefied through the first heat exchanger may be collected at a lower portion of the recovery body 2843.

The recovery suction pipe 2841 connects the top of the storage tank 150 and the recovery body 2843 to each other at a location upstream of the first heat exchanger (based on the flow direction of the gaseous carbon dioxide). Preferably, the recovery suction pipe 2841 will be connected to the recovery body at a position higher than a maximum liquid level of the liquefied carbon dioxide that may be collected in the recovery body in one washing cycle.

The recovery discharge pipe 2842 will also connect the top of the storage tank 150 and the recovery body to each other at a location downstream of the second heat exchanger 2812.

The laundry treating apparatus 1000 may further include a recovery tank 289 located between the pressure vessel 200 and the distillation tank 401 and storing the liquefied carbon dioxide, a first recovery pipe 2891 for connecting the recovery flow path 284 and the recovery tank 289 to each other to flow the liquefied carbon dioxide, and a first recovery valve 2891a positioned on the first recovery pipe 2891 to open and close the first recovery pipe 2891.

In addition, the laundry treating apparatus 1000 may further include a second recovery pipe 2892 for connecting the recovery tank 289 and the distillation tank 401 to each other to flow the gaseous carbon dioxide of the carbon dioxide stored in the distillation tank 401, a second recovery valve 2892a located on the second recovery pipe 2892 to open and close the second recovery pipe 2892, a third recovery pipe 2893 for connecting the recovery tank 289 and the distillation tank 401 to each other to flow the liquid carbon dioxide of the carbon dioxide stored in the recovery tank 289, and a third recovery valve 2893a located on the third recovery pipe 2893 to open and close the third recovery pipe 2893.

First, in the recovery operation, the recovered and liquefied carbon dioxide may be temporarily stored at a lower portion of the recovery body. In addition, the liquid carbon dioxide temporarily collected in the recovery body 2843 in the recovery operation may be flowed to the recovery tank 289 through the first recovery pipe 2891 and stored.

In the recovery operation, the controller 900 will not only operate the recovery compressor 283 and the recovery fan 285, but also open the first recovery valve 2891a to flow the liquefied gaseous carbon dioxide to the recovery tank.

The reason that the recovery tank 289 is located between the pressure vessel 200 and the distillation tank 401 based on the bottom surface of the cabinet is to discharge the liquid carbon dioxide stored in the recovery tank 289 to the distillation tank using the vertical level difference without the separate driving source.

Similarly, the recovery body 2843 may also be located at a location higher than the recovery tank 289 based on the bottom surface of the cabinet.

The reason why the recovery body 2843 is not directly connected to the distillation tank 401 is because the liquid carbon dioxide or the gaseous carbon dioxide may flow back into the directly connected pipe as the pressure of the distillation tank 401 is high.

For example, after discharging the liquid carbon dioxide from the pressure vessel 200, the pressure of the pressure vessel may drop from 40 bar to 10 bar. When the recovery assembly 280 is operated at 10 bar, an amount in a range from 60 to 70 % of the gaseous carbon dioxide remaining in the pressure vessel 200 at 10 bar may be liquefied and recovered.

FIG. 9 shows a recovered CO2 discharge operation of discharging the liquid carbon dioxide stored in the recovery tank 289 to the distillation tank 401 after the recovery operation.

The vertical level at which the recovery tank 289 is located may be higher than the vertical level at which the distillation tank 401 is located. However, the internal pressure of the distillation tank 401 is higher than the internal pressure of the recovery tank 289. Therefore, the liquid carbon dioxide is not able to be discharged from the recovery tank 289 to the distillation tank 401 simply using the vertical level difference.

To solve this, the laundry treating apparatus 1000 may include the second recovery pipe 2892 for connecting the recovery tank 289 and the distillation tank 401 to each other to flow the gaseous carbon dioxide of the carbon dioxide stored in the distillation tank 401, the second recovery valve 2892a located on the second recovery pipe 2892 to open and close the second recovery pipe 2892, the third recovery pipe 2893 for connecting the recovery tank 289 and the distillation tank 401 to each other to flow the liquid carbon dioxide of the carbon dioxide stored in the recovery tank 289, and the third recovery valve 2893a located on the third recovery pipe 2893 to open and close the third recovery pipe 2893.

The controller 900 may close the first recovery pipe 2891 and open the second recovery pipe 2892 and the third recovery pipe 2893 to flow the liquid carbon dioxide stored in the recovery tank 289 to the storage tank 150 without the separate driving source.

The second recovery pipe 2892 is to flow the gaseous carbon dioxide to match the pressures of the recovery tank 289 and the distillation tank 401. In addition, the third recovery pipe may flow the liquid carbon dioxide from the recovery tank 289 to the distillation tank 401 based on the vertical level difference without the separate driving source.

FIG. 10 is a flowchart showing main operations of the washing cycle using the laundry treating apparatus. When the user selects the washing course, a control method of the present invention proceeds to a pressurization preparation operation (S50). In the pressurization preparation operation (S50), the control method of the present disclosure may open the vacuum control valve 687 and operate the vacuum pump 297 to remove the air contained in the pressure vessel 200. This is because, when the air remains in the pressure vessel 200 and contains moisture, a washing power of the carbon dioxide for the laundry may be reduced. Therefore, it is possible to maintain the internal pressure of the pressure vessel 200 lower than the atmospheric pressure, preferably close to the vacuum state.

When the pressurization preparation operation (S50) is completed, the control method of the present disclosure will flow the gaseous carbon dioxide stored in the storage tank 150 to the pressure vessel 200 through the first supply pipe by opening the first supply control valve 625. The control method of the present disclosure may open the first supply control valve 625 until the pressures of the storage tank 150 and the pressure vessel 200 reach the equilibrium pressure. In description using the example shown in FIGS. 6 to 9, the controller 900 will open the first supply control valve 625 and the shared pipe control valve 6801 as the controller 900 must supply the gaseous carbon dioxide through the first supply pipe 621 and the shared pipe 680. This is referred to as a pressurization operation (S100).

When the pressurization operation (S100) is completed, the control method of the present disclosure will replenish the lacking carbon dioxide by opening the replenishment tank 155. The reason the carbon dioxide is insufficient despite being reused is that the carbon dioxide that is not recovered even in the recovery operation is exhausted (S900) to the outside.

To this end, the controller will control the replenishment tank control valve 688 to open the replenishment pipe 683 and supply the insufficient carbon dioxide to the pressure vessel 200. In the example shown in FIGS. 6 to 9, because the replenishment pipe 683 is connected to the shared pipe 680, the control method of the present disclosure may flow the carbon dioxide from the replenishment tank 155 to the pressure vessel 200 by opening the replenishment tank control valve 688 and the shared pipe control valve 6801.

Thereafter, the control method of the present disclosure may flow (S200) the liquid carbon dioxide from the storage tank 150 to the pressure vessel 200. This uses gravity, and the liquid carbon dioxide is able to flow without the separate driving source. To this end, the controller 900 will open the second supply pipe 622 by controlling the second supply control valve 626.

After the liquid carbon dioxide is supplied to the pressure vessel 200, the control method of the present disclosure may proceed to a washing operation (S300) that rotates the drum 300 disposed inside the pressure vessel at a preset first rotation speed to remove the foreign substances on the laundry using a friction force between the liquid carbon dioxide and the laundry. The washing operation (S300) may be performed for a preset first time.

After the washing operation (S300) is completed, the control method of the present disclosure may proceed to a first discharge operation (S350) of discharging the liquid carbon dioxide used inside the pressure vessel 200 to the distillation tank 401.

The first discharge operation (S350) discharges the liquid carbon dioxide using the vertical level difference between the pressure vessel 200 and the distillation tank 401. To this end, the controller 900 may control a discharge control valve 635 to open the discharge pipe 630. In this connection, in order to eliminate the pressure difference between the pressure vessel 200 and the distillation tank 401, the controller 900 may open the shared pipe control valve 6801 and the storage control valve 615 to allow the gaseous carbon dioxide of the pressure vessel to flow from the pressure vessel 200 to the distillation tank 401.

When the first discharge operation (S300) is completed, the control method of the present disclosure may proceed to a first distillation operation (S400) of exchanging heat with the refrigerant for removing the impurities from the liquid carbon dioxide stored in the distillation tank 401. Because the first distillation operation (S400) is the same as the above-described distillation operation, a detailed description thereof is omitted.

Schematically, the controller 900 may operate the distillation compressor 403 that circulates the refrigerant to circulate the refrigerant between the distillation tank 401 and the storage tank 150. Through the heat exchange with the refrigerant, the liquid carbon dioxide may be vaporized in the distillation tank 401, and the gaseous carbon dioxide may be liquefied in the storage tank 150. The controller 900 may open the storage control valve 615 and the first supply control valve 625 to flow the vaporized carbon dioxide from the distillation tank 401 to the storage tank 150 through the storage pipe.

When the first distillation operation (S400) is completed, the control method of the present disclosure will proceed to a liquid CO2 supply operation (S500) for rinsing of supplying the distilled liquid carbon dioxide to the pressure vessel 200 again. The liquid CO2 supply operation (S500) for the rinsing is the same as the liquid CO2 supply operation (S200) for the washing. That is, the controller 900 will control the second supply control valve 626 to open the second supply pipe 622.

After the liquid carbon dioxide is supplied to the pressure vessel 200, the control method of the present disclosure may proceed to a rinsing operation (S600) of rotating the drum 300 disposed inside the pressure vessel at a preset second rotation speed (or a rinsing rotation speed) to remove the foreign substances on the laundry using the friction between the liquid carbon dioxide and the laundry. The rinsing operation (S600) may be performed for a preset second time.

In addition, when the rinsing operation (S600) is completed, the control method of the present disclosure may proceed to a rinsing discharge operation (S650) and a rinsing distillation operation (S700) similar to the first discharge operation (S350) and the first distillation operation (S400), respectively. The controller may control each valve as in the first discharge operation (S350) and the first distillation operation (S400).

For clear foreign substances removal, the liquid CO2 supply operation (S500) for the rinsing, the rinsing operation (S600), the rinsing discharge operation (S650), and the rinsing distillation operation (S700), denoted by SA, may be repeated a plurality of times. Preferably, those may be repeated twice.

When the rinsing distillation operation (S700) is completed, the control method of the present disclosure may proceed to a recovery operation (S800) of recovering the gaseous carbon dioxide remaining in the pressure vessel 200 using the recovery assembly 280.

In the recovery operation (S800), the controller 900 compresses and circulates the refrigerant using the recovery compressor 283, circulates the gaseous carbon dioxide using the recovery flow path 284, and circulates and liquefies the gaseous carbon dioxide remaining in the pressure vessel 200 through the heat exchange with the refrigerant in the recovery heat exchanger 281.

Then, the liquefied carbon dioxide will be flowed to the recovery tank 289 from the recovery flow path 284 and stored in the recovery tank 289. To this end, the controller 900 may control the first recovery valve 2891a to open the first recovery pipe 2891 to flow the liquefied carbon dioxide to the recovery tank 289.

When the recovery operation (S800) is completed, the control method of the present disclosure may proceed to a recovered CO2 discharge operation (S900) of discharging the liquid carbon dioxide from the recovery tank 289 to the storage tank 150. The controller 900 may open the second recovery valve 2892a and the third control valve to flow the gaseous carbon dioxide to the recovery tank 289 and flow the liquid carbon dioxide to distillation tank 401 through second recovery pipe 2892 and third recovery pipe 2893, respectively.

Additionally, the controller 900 may discharge the gaseous carbon dioxide remaining without being recovered to the outside by controlling the purge valve 298 to open the purge pipe 681.

The present disclosure is able to be modified and implemented in various forms, so that the scope thereof is not limited to the above-described implementations. Therefore, when the modified implementation includes the components of the claims of the present disclosure, it should be viewed as belonging to the scope of the present disclosure.

Claims

A laundry treating apparatus comprising:

a pressure vessel configuring for accommodating carbon dioxide therein;

a storage tank configuring for storing carbon dioxide therein to supply carbon dioxide to the pressure vessel;

a distillation tank configuring for accommodating carbon dioxide discharged from the pressure vessel to remove foreign substances dissolved in carbon dioxide discharged from the pressure vessel;

a recovery flow path located outside the pressure vessel to circulate gaseous carbon dioxide of the pressure vessel; and

a recovery heat exchanger located on the recovery flow path to exchange heat with gaseous carbon dioxide passing through the recovery flow path to liquefy gaseous carbon dioxide.
The laundry treating apparatus of claim 1, further comprising:

a recovery body positioned on the recovery flow path to accommodate the recovery heat exchanger therein and store carbon dioxide liquefied through the recovery heat exchanger therein.
The laundry treating apparatus of claim 2, further comprising:

a recovery tank positioned between the pressure vessel and the distillation tank to store liquefied carbon dioxide therein.
The laundry treating apparatus of claim 2, further comprising:

a recovery compressor for compressing and circulating a refrigerant to exchange heat with gaseous carbon dioxide through the recovery heat exchanger; and

a recovery fan positioned on the recovery flow path to circulate gaseous carbon dioxide of the pressure vessel.
The laundry treating apparatus of claim 3, further comprising:

a first recovery pipe for connecting the recovery flow path and the recovery tank to each other to flow the liquefied carbon dioxide; and

a first recovery valve positioned on the first recovery pipe to open and close the first recovery pipe.
The laundry treating apparatus of claim 5, further comprising:

a second recovery pipe for connecting the recovery tank and the distillation tank to each other to flow gaseous carbon dioxide of carbon dioxide stored in the distillation tank;

a second recovery valve positioned on the second recovery pipe to open and close the second recovery pipe;

a third recovery pipe for connecting the recovery tank and the distillation tank to each other to flow liquid carbon dioxide of carbon dioxide stored in the recovery tank; and

a third recovery valve located on the third recovery pipe to open and close the third recovery pipe.
The laundry treating apparatus of any one of claims 1 to 6, further comprising:

a distillation heat exchanger located inside the distillation tank to exchange heat with carbon dioxide stored inside the distillation tank;

a storage heat exchanger located inside the storage tank to exchange heat with carbon dioxide stored in the storage tank;

a distillation compressor for compressing the refrigerant circulating through the distillation heat exchanger and the storage heat exchanger; and

a distillation refrigerant flow path for connecting the distillation heat exchanger, the storage heat exchanger, and the distillation compressor to each other to form a flow path for circulating the refrigerant therethrough.
The laundry treating apparatus of claim 7, wherein the distillation heat exchanger is located inside the distillation tank at a lower portion of the distillation tank,

wherein the storage heat exchanger is located inside the storage tank at an upper portion of the storage tank.
The laundry treating apparatus of claim 7, further comprising a distillation expander for expanding the refrigerant that has passed through the distillation heat exchanger on the distillation refrigerant flow path.
The laundry treating apparatus of claim 9, wherein the distillation refrigerant flow path includes:

a first circulation pipe for connecting the distillation compressor and the distillation heat exchanger to each other to flow the refrigerant compressed in the distillation compressor to the distillation heat exchanger;

a second circulation pipe for connecting the distillation heat exchanger and the distillation expander to each other to flow the refrigerant that has exchanged heat with carbon dioxide stored in the distillation tank from the distillation heat exchanger to the distillation expander;

a third circulation pipe for connecting the distillation expander and the storage heat exchanger to each other to flow the refrigerant cooled through the distillation expander to the storage heat exchanger; and

a fourth circulation pipe for connecting the storage heat exchanger and the distillation compressor to each other to flow the refrigerant that has exchanged heat with carbon dioxide stored in the storage tank from the storage heat exchanger to the distillation compressor.
The laundry treating apparatus of claim 10, wherein a temperature of the refrigerant passing through the second circulation pipe is higher than a temperature of the refrigerant passing through the third circulation pipe.
The laundry treating apparatus of claim 11, wherein a temperature of the refrigerant passing through the distillation heat exchanger is higher than a temperature of the refrigerant passing through the storage heat exchanger.
The laundry treating apparatus of claim 7, further comprising:

a storage pipe for connecting the distillation tank and the storage tank to each other to flow gaseous carbon dioxide stored in the distillation tank to the storage tank.
The laundry treating apparatus of claim 13, wherein the storage pipe connects a top of the distillation tank and a top of the storage tank to each other.
A method for controlling a laundry treating apparatus including a pressure vessel configuring for accommodating carbon dioxide therein a drum rotatably disposed inside the pressure vessel to accommodate laundry therein, a storage tank configuring for storing carbon dioxide therein to supply carbon dioxide to the pressure vessel, and a distillation tank configuring for accommodating carbon dioxide discharged from the pressure vessel to remove foreign substances dissolved in carbon dioxide discharged from the pressure vessel, the method comprising:

a rinsing operation of removing the foreign substances by rotating the drum at a preset rotation speed and using friction between liquid carbon dioxide supplied from the storage tank and the laundry;

a discharge operation of discharging liquid carbon dioxide used in the pressure vessel to the distillation tank when the rinsing operation is completed; and

a recovery operation of liquefying gaseous carbon dioxide remaining in the pressure vessel through heat exchange with a recovery flow path for circulating gaseous carbon dioxide to the outside of the pressure vessel and a recovery heat exchanger located on the recovery flow path, and then, storing liquefied carbon dioxide in a recovery tank located between the pressure vessel and the distillation tank.
The method of claim 15, further comprising:

a distillation operation of, after the discharge operation, vaporizing liquid carbon dioxide stored in the distillation tank through heat exchange with a distillation heat exchanger located in the distillation tank and flowing the vaporized carbon dioxide to the storage tank, and liquefying gaseous carbon dioxide stored in the storage tank through heat exchange with a storage heat exchanger located in the storage tank.