Air conduit system with adsorber, household appliance with air conduit system and method of operating a household appliance

Abstract

An air duct system with a sorption material has a blocking and guiding system which allows a normal operating state of the air duct system without use of the sorption material and a sorption state. The sorption state helps to reduce the drying time and the energy consumption. The air duct system is used in a domestic appliance, such as a laundry dryer or a dishwasher for laundry. The water released during the regeneration of the sorption material can be used for the next washing cycle. Furthermore, a method of operating the air duct system and a computer program for a domestic appliance are disclosed.

Description

TECHNICAL FIELD

[0001] The present invention relates to an air duct system with a sorber, which can be used in household appliances, such as dishwashers and / or laundry drying machines for laundry. BACKGROUND

[0002] In household appliances with a washing process and a drying process, the drying phase is usually supported by a conventional device, such as a heat pump. This process is usually designed at a single operating point. This operating point is chosen so that the drying process has the maximum efficiency for most of its duration. At a certain point, when most of the water has been removed, but when the laundry is still considered to be wet, the efficiency of this heat pump-based drying process starts to decrease. The condensation rate decreases. As a result, the drying time becomes longer.

[0003] By using a drying system with an electric heater instead of a heat pump-based system, the long drying time can be avoided. However, this drying system using only an electric heater is not very energy efficient.

[0004] Furthermore, the drying process can also be carried out in a relatively short time by using sorption materials such as zeolites, silica gels, metal-organic framework (MOF) based substances or other hygroscopic materials. The water sorption process in these materials releases thermal energy. When this sorption drying process is combined with a heat pump drying process, the thermal energy released by the sorption material supports the drying of the air by the heat pump. Thus, the energy efficiency is improved.

[0005] Since the capacity of the sorption material to absorb moisture is limited, regeneration must be carried out. For zeolites, a temperature of approximately 200°C is usually required in the regeneration cycle to expel the moisture. The limited capacity of the sorption material has another disadvantage: the amount of sorption material must be matched to the amount of water to be absorbed from, for example, a full load of laundry in a household appliance, in terms of mass and volume. Therefore, a large amount of sorption material is often required. A commonly used material can only absorb, for example, one third of its mass of water. Therefore, the use of zeolites in the drying system of a laundry drying machine, as described in EP 2935685 A1, is not common. On the other hand, in dishwashers, zeolite technology is considered to be efficient in terms of drying efficiency and energy efficiency and is accepted on the market. SUMMARY

[0006] It is an object of the present invention to provide a technology for using sorption materials in the drying cycle of a household appliance for washing and drying household items, thereby taking advantage of the sorption materials in the drying process while reducing the disadvantages.

[0007] Thus, an air duct system for a household appliance for cleaning and drying household items is described, wherein the household appliance comprises a controller, an air duct embodied to direct an air flow to a compartment for receiving items to be cleaned, wherein the air duct system is embodied to be arranged in the air duct upstream of the compartment, wherein the air duct system has a first duct line and a second duct line, the second duct line being embodied to contain an adsorbent material, wherein the first and second duct lines are respectively provided with a first and a second blocking device, the first and second blocking devices being embodied to open or close the first and second duct lines, respectively, in response to a control signal from the controller, wherein the air duct system is embodied to:

[0008] be operable in a normal operating state, in which the first duct line is opened by the first blocking device and the second duct line is closed by the second blocking device, and

[0009] be operable in an adsorption state, in which the second duct line is opened by the second blocking device.

[0010] This design using an adsorbent material allows the system to work in parallel with the normal operation of a drying process using, for example, a heat pump. When the compressor of the heat pump is also running, the temperature of the air inlet of the compartment containing the household items that have been washed and are being dried can be increased due to the heat energy released in the adsorption process. Thus, the drying process will be accelerated and the energy consumption can be reduced. In other words, this air duct system enables the use of an adsorbent material in a support system of a main drying system.

[0011] In an embodiment, the blocking devices comprise valves, flaps, gates or switches for closing the inlet of the respective duct line, thereby preventing and / or controlling the air flow into the respective duct line.

[0012] According to one embodiment, in this air duct system, in the adsorption state, the first duct line is at least partially closed by the first blocking device.

[0013] In this embodiment, the normal drying process without the use of adsorbent material can continue as long as it still contributes to drying or as long as it is still energy efficient. The normal drying process without the use of adsorbent material can be completely switched off, for example, in the last phase of the drying cycle. If the first duct line is completely closed, the drying process using the adsorbent material can be used as the only drying process.

[0014] According to another embodiment, an air duct system according to the above-mentioned embodiments is described, wherein the second duct line comprises a heater.

[0015] According to another embodiment, the first duct line in the air duct system comprises a heater.

[0016] The purpose of the two embodiments described above is to provide additional heat energy to the compartment that contains household items that have been washed and are being dried. The heater in the second conduit line can also be used for regeneration of the adsorbent material.

[0017] Furthermore, a household appliance for cleaning and drying household items is described, comprising a controller, an air conduit to direct an air flow to a compartment for receiving items to be cleaned, an air conduit system arranged in the air conduit upstream of the compartment, wherein the air conduit system has a first conduit line and a second conduit line, the second conduit line comprising an adsorbent material, wherein the first and second conduit lines are respectively provided with a first and a second blocking device, the first and second blocking devices being arranged to open or close the first and second conduit lines respectively in response to a control signal from the controller, wherein the controller is arranged to operate the conduit system such that:

[0018] there is a normal operation state in which the first conduit line is open by the first blocking device and the second conduit line is closed by the second blocking device, and

[0019] there is an adsorption state in which the second conduit line is open by the second blocking device.

[0020] According to one embodiment of the household appliance, the controller operates the conduit system such that in the adsorption state the first conduit line is at least partially closed by the first blocking device.

[0021] According to another embodiment, the household appliance is a dishwasher.

[0022] According to another embodiment, the household appliance is a washer-dryer for laundry.

[0023] Furthermore, a method of controlling a household appliance for cleaning and drying household items is described, the household appliance comprising a controller, an air conduit to direct an air flow to a compartment for items to be cleaned, and an air conduit system arranged in the air conduit upstream of the compartment, wherein the air conduit system has a first conduit line and a second conduit line, the second conduit line comprising an adsorbent material, wherein the controller is arranged to at least partially open or close the conduit lines, the method comprising a step of causing air to flow through the conduit system towards the compartment, the step comprising:

[0024] a normal operation step in which the controller opens the first conduit line and closes the second conduit line, so that the flowing air passes through the first conduit line, and

[0025] an adsorption step in which the controller opens the second conduit line, so that the flowing air passes through the second conduit line, wherein the normal operation step precedes the adsorption step.

[0026] According to one embodiment of the method, the step of adsorbing comprises the step of at least partly closing the first conduit line by the controller.

[0027] According to another embodiment, the method comprises the step of starting the step of adsorbing by the controller after the step of normal operation has been performed for a first predetermined time, and the step of ending the step of normal operation by the controller after the step of normal operation has been performed for a second predetermined time.

[0028] According to another embodiment, the method comprises the step of starting the step of adsorbing by the controller after the controller determines that the signal level of the sensor exceeds a first predetermined value, and the step of ending the step of normal operation by the controller after the controller determines that the signal level of the sensor exceeds a second predetermined value.

[0029] According to another embodiment, the method comprises the step of starting the step of adsorbing by the controller after the controller determines that the signal level of the sensor is within a first predetermined range for a third predetermined time, and the step of ending the step of normal operation by the controller after the controller determines that the signal level of the sensor is within a second predetermined range for a fourth predetermined time.

[0030] According to another embodiment, when the household appliance is arranged to perform a drying process and a wetting process, during which water is supplied to the compartment, the method comprises a step of regenerating after the step of adsorbing, the step of regenerating comprising:

[0031] the step of flowing air through the second conduit line, the second conduit line being opened by the controller, and

[0032] the step of transporting water released from the adsorption material by the flowing air through the heater into the compartment during the wetting process, wherein the water is adsorbed in the step of adsorbing.

[0033] This method of integrating a regeneration step in the wetting process of the next wash cycle increases the environmental friendliness of the household appliance by reducing the fresh water consumption of the household appliance. In addition, the additional effect is that the amount of water entering the drainage system is reduced, since the water absorbed by the adsorption material is retained by the adsorption material. In the next wash cycle, this water is released from the adsorption material and used, instead of being drained. Since this water is adsorbed in the form of water vapor, it is clean and can be used in the next wash cycle.

[0034] According to another aspect, the invention relates to a computer program carrier comprising instructions which, when the program is executed by a computer, cause the computer to perform any of the above-mentioned methods.

[0035] The embodiments and features described with reference to the air duct system of the present application are applicable to the household appliance of the present application mutatis mutandis.

[0036] The embodiments and features described with reference to the air duct system of the present application are applicable to the method of the present application mutatis mutandis.

[0037] Other possible implementations or alternative solutions of the present application also encompass combinations of the features described above or below with respect to the embodiments, even if not explicitly mentioned. The skilled person can also add to the most basic form of the present application individual or isolated aspects and features. BRIEF DESCRIPTION OF DRAWINGS

[0038] Other embodiments, features and advantages of the present application will become apparent from the subsequent description and technical solutions, taken in conjunction with the accompanying drawings, in which:

[0039] Figure 1 A conventional drying apparatus using a sorber in a household appliance is shown;

[0040] Figure 2 A drying apparatus in a household appliance is shown, having an air duct system comprising a sorber;

[0041] Figure 3 is a schematic view of the air duct system in a normal operating condition;

[0042] Figure 4 is a schematic view of the air duct system in a sorbing condition;

[0043] Figure 5 is a schematic view of the air duct system according to a variant;

[0044] Figure 6 is a flow chart explaining a method of operating the air duct system;

[0045] Figure 7 is a flow chart explaining a first variant of the method of operating the air duct system;

[0046] Figure 8 is a flow chart explaining a second variant of the method of operating the air duct system;

[0047] Figure 9 is a flow chart of a method for regenerating the sorption material. DETAILED DESCRIPTION

[0048] In the drawings, like reference numerals refer to like or functionally equivalent elements, unless otherwise indicated.

[0049] The drying system shown here is a heat pump. The operation of this heat pump follows the same principle as a normal refrigerator. In addition to a heat pump, other drying systems can also be used. One example is a drying system comprising a heater, wherein the air passing through the drying system is heated by means of a heating fluid, which can flow through the drying system in a direction transverse to the direction of the air flow or in a flow direction opposite to the direction of the air flow. Such a drying system with a heater comprises a container or an outlet for condensed moisture, i.e. water removed from the air coming out of the compartment for the items to be cleaned. In addition, an electric heater can also be used as a drying element in the drying system.

[0050] Figure 1 is a schematic diagram of the air circulation in a drying system of a conventional household appliance 10, such as a dishwasher or a laundry dryer for laundry. The household appliance is equipped with a sorber. A fan 3 pushes the air to a heater 4 and from there into the sorber system 5. The drying air is then supplied into a compartment 6 for items that have been washed or cleaned and are being dried. This air flow influences the drying process of the household items (dishes, laundry) in the compartment. In Figure 1 and Figure 2 In the example of a household appliance 1, the compartment has a cylindrical shape typical of a laundry dryer drum. In the air discharge path, there can be a sensor 15 for, for example, temperature, relative humidity, electrical conductivity. Since there is a second sensor (not shown) on the side where the air is supplied into the compartment, the temperature difference, the relative humidity difference before and after the compartment with the household items can also be measured. Of course, more than one sensor can also be used so that, for example, both the temperature and the humidity can be measured. The signal of the sensor 15 is transmitted to a controller 16 by means of a connection 17, which is usually a microprocessor that performs process control for the household appliance 1. The air passes through a filter from the sensor and returns to the drying system 2 through an air duct 8. Here, a heat pump is used as the drying system 2. The heat pump comprises a compressor 21, a first heat exchanger 22 in which the refrigerant is at least partially condensed, a throttling valve 23 that expands the refrigerant, and a second heat exchanger 24 in which the refrigerant is evaporated. The air flow passes through both heat exchangers, as indicated by the arrows. When the air carrying water from the compartment 6 with the items to be dried passes through these heat exchangers 22 and 24, heat is transferred to the heat exchangers, and the flowing air will be cooled. This temperature drop causes the moisture in the air to condense. Thus, the air has been dried and flows back from the drying system 2 to the inlet side of the fan 3. Thus, the drying cycle starts again and can be repeated until the household items in the compartment 6 are considered to be dry.

[0051] Figure 2 is a schematic diagram of the air circulation in a drying system of a conventional household appliance 1, which is equipped with an improved arrangement of sorbers in the air duct system. Most of the components in this household appliance are the same as in Figure 1The components shown are the same. Figure 2 The overall use of and Figure 1 The same reference numerals are used in the accompanying drawings. However, as air leaves heater 4, a guiding and blocking system 52 exists to guide the airflow to the lower junction. Figures 3-5 In a pair of conduit lines described in detail. The guiding and blocking system 52 is operated via a controller 16 through a second connection 18. From Figure 2 As can be seen, air from the heater is directly delivered through the first conduit to the compartment 6 containing the items to be dried via the guide and block system 52. The guide and block system 52 also directs air into a second conduit containing the adsorbent material 51. From there, air also flows into the compartment 6 through the second conduit. The adsorbent materials used in this household appliance 1, which has both first and second conduits, are the same as those mentioned in the introduction of this specification.

[0052] Figure 3 This is a schematic diagram of the air duct system 112 in normal operating condition, showing the first duct line 110 and the second duct line 111. Guiding / Blocking System ( Figure 2 Reference numeral 52) in the attached diagram constitutes two blocking devices, shown here as gates 90 and 91, which can also be implemented as stoppers, valves, baffles, or converters. Gate 90 is located in the first conduit 110, and gate 91 is located in the second conduit 111. Figure 3 In the normal operating state shown, gate 90 is fully open and gate 91 is fully closed. Therefore, all air flowing into the air duct system 112—such as… Figure 3 Arrows 140 and 141 on the left indicate that the air will pass through the first conduit 110 and exit the air duct system 112. Figure 3 As indicated by arrow 140 on the right. In normal operating mode, no adsorption material is used during the drying process. The drying process in normal mode is the same as that of traditional household appliances that do not use an adsorbent. Figure 4 and 5 In that way, Figure 3 Additional components are shown in the second conduit 111 of the air duct system 112. Adsorbent material 121 may be applied to the wall of the second conduit 111. Alternatively or additionally, adsorbent material 120 may be contained in a container 13 arranged within the second conduit 111. In this case, the adsorbent material 120 is in particle form (e.g., beads, pellets, or granules). A heater 101 may also be arranged within the second conduit 111. This heater 101 can function as a heater during regeneration and can also support… Figure 2 Heater 4 in the middle.

[0053] Generally, if the drying cycle is performed in a conventional way, i.e. in the normal operating mode, it is observed that the drying is quite effective within a certain time. However, when the drying cycle tends to end and a certain amount of humidity is still left in the compartment to be removed, e.g. 10-20% of humidity is still left in the compartment to be removed, the drying speed and condensation rate will decrease. Then, continuing only in the normal operating mode will result in a longer drying time.

[0054] Figure 4 is a schematic view of the air conduit system 112 in the adsorption state, showing the first conduit line 110 and the second conduit line 111. The components and reference numerals are the same as in Figure 3 . The difference between the normal operating state and the adsorption state is that in the adsorption state the shutter 90 is closed and the shutter 91 is open. The shutter 90 shuts off the air flow 140 on the Figure 4 left side into the first conduit line 110. When the shutter 91 is open, the air flow 141 on the Figure 4 left side into the second conduit line 111 passes the adsorption material 121 and through the container 13 with the adsorption material 120 to the Figure 4 outlet of the second conduit line 111 on the right side. From there, the air flow flows along the conduit to the compartment 6.

[0055] This adsorption state is most helpful to alleviate the problem that occurs when the drying cycle tends to end, at which point the drying efficiency decreases after most of the humidity has been removed from the compartment with the household items. When switching to the adsorption state, the drying process will also become much faster due to the moisture absorbing capacity of the adsorption material, especially when the drying cycle tends to end.

[0056] Figure 5 is a schematic view of the air conduit system 112 in a third state, in which the shutter 90 in the first conduit line 110 is partially closed and the shutter 91 in the second conduit line 111 is partially open. This third state is considered a variant of the adsorption state, because the adsorption material 120, 121 is exposed to the flowing air 141 in this state as in the adsorption state. Thus, the adsorption material 120, 121 at least supports the drying process.

[0057] Figure 5 An additional heater 100 in the first conduit line 110 is also shown. This combination of the heater 100 in the first conduit line 110 and the heater 101 in the second conduit line 111 can support or even replace the heater 4 in Figure 2 .

[0058] Figure 6is a flow chart explaining a method of operating an air conduit system. In step S1, the drying process is started. In step S2, the drying system is running and the air conduit system 112 is in a normal operating state, as shown in Figure 2 step S3, the controller determines whether a first condition for starting the adsorption step is met. One example of this first condition is that the controller determines whether a first predetermined time has elapsed. If this condition is not met, the drying system will continue running step S2. If, on the other hand, this condition is met, the controller will continue with step S4 and open the gate 91 so that moisture in the air stream 141 can be absorbed by the adsorption material 120, 121.

[0059] In step S5, the controller determines whether a second condition for ending the normal operating step is met. One example of this second condition is that the controller determines whether a second predetermined time has elapsed. This second predetermined time can be longer than, equal to or shorter than the first predetermined time. If this condition is not met, the drying system will continue running step S4 and the gate 91 is open. If, on the other hand, the second condition is met, the controller will continue with step S6 and at least partially close the gate 91. The gate 90 can also be gradually closed over time in step S6. If the gate 90 is fully closed in step S6, the air conduit system 112 will be in an adsorption state. When the gate 90 is fully closed, the controller will also switch off the drying system 2, i.e. the compressor 21 or the corresponding heater. In this state, drying is only active through the adsorption material. The drying system 2 is no longer needed. Of course, the fan 3 will continue to run and circulate air through the second conduit line 111, the compartment 6 and the air conduit 8, thereby running the drying in the adsorption state. When the drying system is run in the adsorption state at the end of the drying cycle with the drying system 2 switched off, the energy consumption of the household appliance is reduced. Figure 4

[0060] In step S7, the controller 16 will determine whether the drying process is completed, for example by determining whether a third predetermined time has elapsed or based on the signal of the humidity sensor 15. If the drying process is completed, in step S8 the controller will terminate the drying process and continue its program cycle by, for example, releasing the door lock of the household appliance 1. In step S9, the drying process is ended.

[0061] Apart from two steps, Figure 7 are the same as Figure 6 in Figure 7 , Figure 6 ​Step S3 is replaced by step S31 and step S5 is replaced by step S51. All other steps are identical for both figures. Their description will not be repeated. In step S31, the controller determines whether the signal level of sensor 15 exceeds a first predetermined threshold. Exceeding the first predetermined threshold is another example of satisfying the first condition. If the first predetermined threshold has not been exceeded, the drying system will continue with step S2. If, on the other hand, the first predetermined threshold has been exceeded, the controller will continue with step S4.

[0062] In step S51, the controller determines whether the signal level of sensor 15 exceeds a second predetermined threshold. Exceeding the second predetermined threshold is another example of satisfying the second condition. If the predetermined threshold has not been exceeded, the drying system will continue with step S4 and the gate 91 is opened. If, on the other hand, the second predetermined threshold has been exceeded, the controller will continue with step S6.

[0063] Except for two steps, Figure 8 are also identical to Figure 6 In Figure 8 , Figure 6 Step S3 is replaced by step S32 and step S5 is replaced by step S52. All other steps are identical for both figures. Their description will not be repeated. In step S32, the controller determines whether the signal level of sensor 15 has been within a predetermined first range for a predetermined first time. If not, the controller 16 will continue with step S2. If the signal level of sensor 15 has been within a predetermined first range for a predetermined first time, the controller 16 will continue with step S4.

[0064] In step S52, the controller determines whether the signal level of sensor 15 has been within a predetermined second range for a predetermined second time. If not, the controller 16 will continue with step S2. If the signal level of sensor 15 has been within a predetermined second range for a predetermined second time, the controller 16 will continue with step S4.

[0065] Figure 9 is a flow chart of a method for regenerating adsorption material. Basically, the method uses the water that has been adsorbed by the adsorption material in the last drying cycle by releasing the water, i.e. by regenerating the adsorption material for the next washing cycle. Thus, fresh water consumption can be reduced. When the adsorption material is a zeolite, it has to be heated to several hundred degrees Celsius so that the water that has been adsorbed in the drying cycle is expelled from the adsorption material in order to be ready for the next drying cycle.

[0066] In step Sll, the next washing cycle and regeneration cycle is started. In step S12, air is flowed through the second conduit line containing the adsorbing material which is heated in step S13 to a temperature at which the adsorbed water will be released. In step S13, the heater is set for regeneration, i.e. for zeolites, to a higher setting than in the drying mode. A heater different from the air heater can be used which will mainly heat the adsorbing material itself and less the air surrounding the adsorbing material. If the adsorbing material is realized in the form of a wall coating, then electric heating wires can be embedded in the wall coating. If the adsorbing material is realized in the form of beads, pellets or granules, then the electric wires of the heater can be arranged in close contact with the beads, pellets or granules. In step S14, the controller 16 determines whether the wetting part of the washing cycle has been completed. If not, the process continues with steps S13 and S18. In step S18, the wetting process of the washing cycle is started by introducing fresh water from the water supply. Step S18 can be started after steps S12 and S13. In step S15, the wetting process by means of the water supply is terminated. The controller can also start the next step of the washing cycle, like rotating the drum chamber to achieve washing in this step S15. In step S16, the controller determines whether the regeneration cycle has been completed. If not, in step S19, the controller 16 switches from supplying air to the compartment to an alternative air exhaust which can be connected to a drain line or a condenser. In step S20, similar to step S16, the controller 16 determines whether the regeneration cycle has been completed. If not, the controller 16 will continue to operate the heater and the air flow to the alternative air exhaust in step S19. Otherwise, i.e. if the controller determines in step S16 or step S20 that the regeneration cycle has been completed, in step S17, the controller will reduce the heater and the air flow. The combined wetting and regeneration process is terminated in step S22.

[0067] Although the application has been described in terms of preferred embodiments, it will be apparent to those skilled in the art that modifications can be made in all embodiments.

[0068] List of reference signs

[0069] 1, 10 household appliance

[0070] 2 drying system

[0071] 3 fan

[0072] 4 heater

[0073] 5 adsorbing system

[0074] 6 compartment for items to be cleaned

[0075] 7 air filter

[0076] 8 air conduit

[0077] 10 Household appliance with adsorber

[0078] 15 Sensor

[0079] 16 Controller

[0080] 17 Sensor connection

[0081] 18 Connection for guiding / blocking system

[0082] 21 Compressor (dryer pump)

[0083] 22 Heat exchanger (condenser)

[0084] 23 Throttle (choke element)

[0085] 24 Heat exchanger (evaporator)

[0086] 51 Adsorber material

[0087] 52 Guiding and blocking system

[0088] 90 Guiding and blocking first line

[0089] 91 Guiding and blocking second line

[0090] 100 Heater of first line

[0091] 101 Heater of second line

[0092] 110 First duct line

[0093] 111 Second duct line

[0094] 112 Air duct system

[0095] 120 Adsorber material (beads)

[0096] 121 Adsorber material (wall coating)

[0097] 13 Container for adsorber material

[0098] 140 Air flow first line

[0099] 141 Air flow second line

[0100] CT Control signal

Claims

1. A method for controlling a household appliance (1) for cleaning and drying household items, the household appliance (1) comprising... Controller (16); air duct (8) that directs airflow to a compartment (6) for items to be cleaned; air duct system (112) arranged upstream of the compartment (6) in the air duct (8); in, The air duct system (112) has a first duct (110) and a second duct (111), the second duct containing absorbent material (120, 121). The controller is configured to at least partially open or close the first conduit (110) and the second conduit (111). The method includes the step of directing air through an air duct system (112) to the compartment (6), the step of which includes: In the normal operation step (S2), the controller (16) opens the first conduit (110) and closes the second conduit (111), thereby allowing air to flow through the first conduit (110), and In the adsorption step (S4), the controller (16) opens the second conduit (111), allowing air to flow through it. The normal operation step (S2) includes a drying process without using adsorbent material, and this normal operation step (S2) is performed before the adsorption step (S4). The household appliance (1) is arranged to perform a drying process and a wetting process, during which water is supplied to the compartment (6), and the method includes a regeneration step (S12, S13) after the adsorption step (S4), the regeneration step including: In step (S12), which allows air to flow through the second conduit (111), the second conduit (111) is opened by the controller (16), and In the step (S13) where water is transported into the compartment by flowing air during the wetting process, water is released from the adsorbent material (120, 121) by heaters (4, 101), wherein water is adsorbed in the adsorption step (S4).

2. The method according to claim 1, wherein, The adsorption step (S4) includes the step (S6) of at least partially closing the first conduit line (110) by the controller (16).

3. The method according to claim 1 or 2, wherein, The method includes: After the normal operation step (S2) has been performed for a first predetermined time, the adsorption step (S4) is initiated by the controller (16); and After the normal operation step (S2) has been performed for a second predetermined time, the normal operation step (S2) is terminated by the controller (16) in step (S6).

4. The method according to claim 1 or 2, wherein, The method includes: After the controller (16) determines that the signal level of the sensor (15) exceeds a first predetermined value, the controller (16) initiates the adsorption step (S4); and After the controller (16) determines that the signal level of the sensor (15) exceeds the second predetermined value, the controller (16) terminates the normal operation step (S2) step (S6).

5. The method according to claim 1 or 2, wherein, The method includes: After the controller (16) determines that the signal level of the sensor (15) is within a first predetermined range for a third predetermined time, the controller (16) initiates the adsorption step (S4); and After the controller (16) determines that the signal level of the sensor (15) is within the second predetermined range for a fourth predetermined time, the controller (16) terminates the normal operation step (S2) (S6).

6. A computer program carrier including instructions that, when executed by a controller (16), cause the controller (16) to perform the method according to any one of claims 1-5.

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