WO2023174978A1

WO2023174978A1 - The use of ozone in cleaning reusable water containers

Info

Publication number: WO2023174978A1
Application number: PCT/EP2023/056554
Authority: WO
Inventors: Ulf STENERHAG; Martin Renck; Mattias LISS; Hector CAMARA
Original assignee: Wayout International Ab
Priority date: 2022-03-18
Filing date: 2023-03-15
Publication date: 2023-09-21
Also published as: SE2250343A1

Abstract

There is provided a method comprising a) providing a container, where said container having a volume of from 2 liters to 60 liters, b) rinsing the interior of the container with water, c) filling the container with water intended for drinking, and closing the container where the container is made of metal and the water in step b) or step c) has an ozone concentration of from 1 ppm to 10 ppm.

Description

The use of ozone in cleaning reusable water containers

Field of the invention

This invention relates to the distribution of drinking water in reusable containers, o

The use of ozone as a disinfectant of plastic bottles for potable beverages is known. However, the use of ozone in plastic bottles has drawbacks. One such drawback is that the ozone may react with the plastic material in the bottle. This may cause the material to become brittle. Moreover, unsuitable compounds may be released into the water. Furthermore, prolonged exposure to ozone maybe harmful to persons that are working close to the filling equipment.

Furthermore, it would be desirable to provide water from a dispensing station in an even and fast stream with a reduced risk of air locks and without a bubbling sound.

This invention solves this and other problems.

Summary of invention

In a first aspect of the invention there is provided a method comprising a) providing a container, where said container having a volume of from 2 liters to 60 liters, b) rinsing the interior of the container with water, c) filling the container with water intended for drinking, and closing the container where the container is made of metal and the water in step b) or step c) has an ozone concentration of from 1 ppm to 10 ppm. By using a metal container, a higher concentration of ozone can be used. This increases the removal of harmful microorganisms.

In a preferred embodiment both the water used in step a) and b) has an ozone concentration of from 1 ppm to 10 ppm.

This provides a simple rinsing and washing procedure and also provides additional sanitation. It is preferred that the ozonated water comes from the same source.

The ozone concentration may be from 2 ppm to 5 ppm.

Ozonated water may be the only agent used to clean or sanitize the container. This makes it unnecessary to use sodium hydroxide or other additional compounds to clean the containers.

In a preferred embodiment the method comprises the additional step d) of providing the container to a user. The containers may be reused. Hence steps b) and c) may be carried out at a first time and a second time with the same container, where the container is provided to an end user who dispenses at least some of the water from the container between the first time and the second time.

In a second aspect of the invention there is provided a water filling system comprising a water purification system with a water supply, an ozonation unit and a water rinsing and filling device, the system being arranged to provide water from the water purification system to the ozonation unit and from the ozonation unit to the rinsing and filling device, the rinsing and filling device comprising a second connector having first and second outlets, the second connector being configured to connect to a first connector of a water container such that the first outlet is connected to a first conduit of the container in an airtight manner and the second outlet is connected to a second conduit of the container in an airtight manner, the rinsing and filling device being configured to provide ozonated rinsing water from the first outlet to rinse the interior of the container and configured to collect used rinsing water from the container in the second outlet, where the water filling system comprises a recirculation loop for collecting used rinsing water from the second outlet of the rinsing and filling device, the recirculation loop being arranged to provide water to the water purification system, where the recirculation loop has an ozone destructor.

By having a recirculation loop the waste of water in the system is minimized. Prolonged exposure to ozone may be harmful. By collecting the ozone in a controlled way and having an ozone destructor, the exposure to ozone around the system is minimized.

The water rinsing and filling device may be configured to fill a connected container with ozonated water provided from the ozonation unit.

The concentration of ozone in the rinsing and filling water may be from 1 to 10 ppm.

At least some water from the recirculation loop is preferably filled into a container. Hence, at least some of the recirculation loop is subsequently consumed by an end user.

The rinsing and filling device may be arranged to fill a connected container, and any overfill is collected in the first outlet and provided to the recirculation loop.

The ozone destructor may be provided on a recirculation tank which is a part of the recirculation loop.

The accompanying drawings form a part of the specification and schematically illustrate preferred embodiments of the invention, and serve to illustrate the principles of the invention.

Fig. la is a schematic section of a container

Fig. lb is a schematic cross section of a container seen from above. Fig. 2 is a schematic perspective view of an example of a water container, different from the ones in Fig. la and lb.

Fig. 3 is an example of water container.

Fig. 4a is a schematic drawing of a water filling system.

Fig. 4b is a schematic drawing of a water filling system where ozonated rinsing water is being collected in a recirculation loop.

Fig. 5 is a schematic drawing of a water container connected to a rinsing and filling device.

Fig. 6 is a schematic drawing of parts of a rinsing and filling device.

Fig. 7 is a drawing of a container connected to a dispensing station.

Fig. 8 is a diagram of parts of control circuitry for a dispensing station.

Fig. 9 is a schematic drawing of a container connected to a dispensing station.

Fig. 10 is a schematic drawing of a water distribution system.

Figs. 11- 12 are flowcharts.

Fig. 13 is a flowchart with accompanying schematic drawings.

Figs. 14a and 14b are schematic drawings of a container connected to a dispensing station or a rinsing and filling device, seen from above.

Detailed description

As used herein in relation to ozone, parts per million (ppm) refers to milligrams of ozone per liter of water (mg/liter).

A container 1 is used for the distribution of potable water. The container 1 may have a volume of from 2 to 60 litres, more preferably 3-30 litres and even more preferably from 4 to 25 litres. The container 1 is preferably portable when filled with water. For example, the container 1 may have a handle 13 for carrying the container. The container 1 may be suitable for distribution to an end user that dispenses water from the container.

Fig. la shows a container with a lower end 3 and upper end 4. When the container 1 is connected to a rinsing and filling device 54 or a dispensing station 80 (described below), the lower end 3 will typically be downwards. Hence the container 1 may then be supported by the rinsing and filling device 54 or the dispensing station 80.

The container 1 is preferably reusable. The containers 1 should preferably be easy to clean and preferably have a low weight and be durable in order to allow use many times. The number of use cycles is preferably predicted to be from 10 - 1000 for an individual container 1. Each cycle may comprise filling the container 1 with at least some water and providing the container to an end user who dispenses at least some water. Hence, the containers 1 are preferably suitable for repeated filing and distribution to an end user.

An end user is some who dispenses some of the filled water from the container 1, for example for using the water as drinking water. The end user is typically located at a location that is different from the water filling system 50 and the container is typically transported from the water filling system 50 to the end user. Dispensing water from the container 1 typically involves opening a valve of the container 1.

The container 1 is preferably of metal, which preferably is stainless steel or aluminium, where stainless steel is preferred. Other suitable materials include PET (polyethylene terephthalate), polypropylene and polyethylene. Such materials can be reinforced with glass fiber or carbon fiber.

The container 1 may have any suitable shape, for example a cylindrical shape. An example of a container 1 is seen in Fig. la and lb. An example is also shown in Fig. 2. In a preferred embodiment the container 1 is essentially cylinder shaped where the bases are bowlshaped, as in Figs la and lb.

The container 1 preferably has at least one conduit 6, 7 from the exterior of the container to the interior of the container 1 for rinsing the interior of the container l and filing the container 1 with water. In a preferred embodiment the container 1 has a first conduit 6 and a second conduit 7. The first and second conduits 6, 7 are preferably arranged in a lower end 3 of the container 1. The first conduit 6 is preferably connected to an internal extended nozzle 8. The extended nozzle 8 is a pipe, which has an opening 10, directed towards the interior surface 9 of the upper end 4 of the container 1. Preferably the opening 10 is the only opening of the extended nozzle 8 inside the container 1. The extended nozzle 8 is preferably vertical when the container 1 is arranged with the lower end 3 downwards. The extended nozzle 8 preferably ends a short distance from the interior surface 9 of the upper end 4 of the container 1, preferably at most 5 cm, and even more preferably at most 2 cm from the surface 9. The volume above the opening 10 is preferably at most 10 %, even more preferably at most 5% of the total volume of the container 1. The extended nozzle 8 is preferably straight. The extended nozzle 8 is preferably made of metal, or other ozone compatible material. The extended nozzle 8 may be an extension of the first conduit 6. The extended nozzle 8 is preferably arranged to spray water from opening 10 towards the interior surface 9 of the upper end 4 of the container 1. The interior surface 9 of the upper end 4 of the container 1 is preferably bowl-shaped in order to receive the water spray, and to distribute the flow of water on the inner walls 11 of the container 1 (Fig la). This rinses the interior walls 11 of the container 1.

The container 1 may be partly cylinder shaped, where the upper and the lower ends are arranged at the opposite bases of the cylinder. The extended nozzle 8 is preferably arranged in the axis of the cylinder.

The second conduit 7 preferably has an opening 21 that opens to the to the interior of the container at the lower end 3 of the container 1. The opening 21 should be arranged below opening 10 of extended nozzle 8.

The container 1 preferably has a connector 12 through which the container 1 can connect a second device. This preferably connects the conduits 6, 7 as described below. The second device can be rinsing and filling device 54 or a dispensing station 80, as described in more detail below. The connector 12 is preferably arranged at the lower end 3 of the container 1. Each conduit 6, 7 of the container 1 may have a valve. The valve may be a self-closing valve. For example, the valve may be spring loaded, such that the valve is closed unless the spring is counter-acted in some manner. The first connector 12 may be arranged to open the valves when being connected the second connector 55 or third connector 81. When a self-closing valve is used, it is preferably in a closed state when the first connector 12 is not mechanically coupled to second connector 55 or third connector 81 and in an open state when coupled to second connector 55 or third connector 81. Hence connecting the first connector 12 to the second connector 55 or third connector 81 preferably opens the valves of the first and second conduits 6, 7 of the container 1, and disconnecting the first connector 12 closes the valves.

The first connector 12 may hence be able to mechanically engage with the second 55 and third connector 81. The connectors 12, 55, 81 may have a suitable locking mechanism that is operable by a user or which is automatically operated by rinsing and filling device 54. The first, second and third connectors 12, 55, 81 are preferably arranged to ensure that the correct conduit 6, 7 is connected to the correct outlet or that the container 1 has a predetermined orientation. This may be ensured by a directional fit or keying between the first connector 12 and the second connector 55 and the fist connector 12 and the third connector 81. For example, a bayonet coupling may be used. In general, the second and third connector 55, 81 may have a similar or identical shapes.

Hence, when the container 1 is connected to the second or third connector 55, 81, the container 1 may have a predetermined orientation. This may be used to ensure that an identification tag 5 of the container 1 can be read by a tag reader 85 with a short range of detection (Figs 14a, 14b).

In some embodiments the first and second conduits 6, 7 of the container 1 are arranged separately from the connector 12 of the container 1. The first and second outlets 57, 58 of the rinsing and filling device 54 are then in a corresponding manner arranged separately from the second connector 55, and connector 81 of the dispensing station 80 is then arranged in the same manner.

The container 1 is preferably airtight . When a conduit 6, 7 of the container 1 is connected to a second device such as rinsing and filling device 54 or dispensing station 80, the container 1 may form a closed space with a part of the rinsing and filling device 54 or dispensing stion 80. The closed space may be airtight. For example, the connectors 12, 55 81, may have appropriate gaskets. Hence the connectors 12,55, 81 should be such that air, water or ozone does not escape from the filling system 50. In particular connections between the first and second conduits 6,7 and the first and second outlets 57, 58 of the rinsing and filling device 54 may be airtight and the connections between the first and second conduits 6, 7 and the water dispensing conduit 82 and air inlet conduit 84 of dispensing station 80 may be airtight.

In particular, the connectors 12, 55, 81 may be a connector of the type often used for beer kegs. Examples of such beer keg valves include D-type coupler, U-type coupler, G-type coupler, S-type coupler, A type coupler and M type coupler, or modified versions of these. These couplers provides first and second conduits 6, 7, self-closing valves and a connector 12, 55, 81.

Container 1 may have an identification tag 5, such as a RFID tag such as for example an NFC tag (Near Field Communication) attached to it. The tag 5 may have stored thereon a unique identity of the container 1. The tag 5 may for example comprise an antenna that sends a signal when it receives a signal. A RFID tag may be a passive RFID tag. The identification tag, in particular a NFC tag is preferably arranged at the lower end 3 of the container, preferably at the lower half of the height of the container 1, even more preferably at the lower 25% of the height of the container 1, and most preferably at the lowest 10 % of the height of the container 1. This ensures that the tag 5 can be read by a tag reader 85 in the dispensing station 80 or the rinsing and filling device 54. NFC tags typically has short detection range, and this arrangement ensures that the tag reader 85 detects the identification tag 5 of the container 1 attached to the dispensing station 80 and not of a random container 1 standing in the vicinity of the dispensing station 80.

Fig. 3 shows how a container has a handle 13 in the lower end 3, hence the container 1 may be carried with the lower end 3 upwards in some embodiments. The container 1 may have a rime 14 in the lower end for protecting the connector 12. The tag 5 may be placed on the inside of the rim 14. In Fig 3, the connector 12 is covered by a detachable lid 15 which protects the connector 12 during transport.

Looking at Fig. 4a, a filling system 50 for rinsing and filling containers 1 may comprise a water supply 51 for providing water, for example regular tap water or water from a different source such as a river or a lake. The water may be treated in water treatment unit 52, in order to produce potable water. For example, the water may be cleaned using any suitable technology such as filters, UV light, reverse osmosis or AOP, or similar technologies. Treated water may be stored in storage tank 53 and drawn from the storage tank 53 using pump 63. The filing system 50 may comprise an ozonation unit 64. The water is ozonated in ozonation unit 64 and then brought to rinsing and filling device 54.

The rinsing and filling device 54 (Fig. 5) has a second connector 55 which is connectable to first connector 12 of the container 1. The rinsing and filling device 54 may have at least one first outlet 57 that connects to a first conduit 6 of the container 1 when the first and second connecters 12, 55 are engaged. The rinsing and filling device 54 also preferably has a second outlet 58 which connects to the second conduit 7 of the container 1. The first outlet 57 preferably provides rinsing water to the first conduit 6. The second outlet 58 preferably fills the container with water. It should be noted that the water coming from fist and second outlets 57, 58 preferably comes from the same source, preferably the ozonation unit 64 or directly from water treatment unit 52. The second outlet 58 may also be used to allow air to escape during injection of rinsing water also collect used rinsing water from the container 1. The second conduit 7 and the second outlet 58 are preferably used to allow air to escape during rinsing. Rinsing and filling device 54 delivers water trough first and second outlet 57, 58 at a suitable pressure which may be from 2 to 5 bars. The pressure during rinsing is selected so that a suitable washing action of the container 1 is achieved during rinsing. Rinsing and filling device 54 may comprise at least one flow sensor for detecting the amount of water delivered to a container 1 during rinsing or filling.

The second connector 55 is preferably arranged on the rinsing and filling device 54 such that the extended nozzle 8 of the container 1 points upwards when the container 1 is engaged with the rinsing and filling device 54 using the first connector 12. This enables the extended nozzle 8 to spray water into the upper end 4 of the container 1 such that water flows down over the interior of the walls 11 of the container 1.

The rinsing and filling device 54 comprises suitable tanks, piping, water pumps and air pumps, valves and sensors and control circuitry to carry out rinsing and filling. The valves and pumps may be controlled by suitable software and hardware. Example of suitable rinsing and filling devices 54 include MICROMAT M 2/2-b provided by m+f KEG-Technik GmbH & Co. KG, Bottrop, Germany.

Fig. 6 shows a schematic overview of an example of parts of a rinsing and filling device 54. Sensor 60 is a sensor that senses when water comes from the extended nozzle 8 during the filling of the container 1 and may be used to stop filling the container 1. Sensor 60 may be pressure sensor, a conductivity meter or similar.

The filling and rinsing device 54 may be configured to carry out a rinsing and filling cycle for a connected container 1, for example as described below with reference to Fig. 11 (steps 100-102).

In some embodiments ozonated water is used. The concentration of ozone in the water used for rinsing or filling is preferably at least 1 ppm, more preferably at least 2 ppm and even more preferably at least 3 ppm. An upper limit of the ozone concentration may be 50 ppm. The concentration may be for example from 1 ppm to 10 ppm, more preferably from

2 ppm to 5 ppm. This provides for an efficient elimination of microorganisms.

Ozone is preferably generated on site due its low half-life. Machines for generating ozonated water are known. These produce ozone by splitting O2 into single oxygen atoms using high voltage or UV light. The single oxygen atoms will then combine to O3 to a certain extent. The ozone may be introduced into the water using a venturi injector, a static mixer or diffusion stones, for example. A useful ozonated water generator is OZONFILT® OZVb from ProMinent GmbH, Heidelberg. The ozone concentration in the water can be determined using an ozone analyser. The concentration of ozone in the water is determined by pressure, temperature and also, to a lesser extent of pH and mineral content in the water.

The filling system 50 may have recirculation a loop 56 for collecting used rinsing water from the container 1 and providing it back to the water treatment unit 52. The recirculation loop 56 may collect the rinsing water from second conduit 7 for example, as seen in Fig. 4b. Moreover, any water spill from filling the container may be collected in recirculation loop 56. Air that escapes during rinsing or filling or air used to purge the container 1 (from first and second conduits 6, 7) may also be collected in recirculation loop 56. Hence all residual ozone will preferably be collected in recirculation loop 56.

The recirculation loop 56 may have a pump for providing water to the water treatment unit 52.

Recirculation loop 56 may have an ozone destructor 61 for collecting and destroying ozone. The ozone destructor 61 may for example be a catalytic ozone destructor or a thermal ozone destructor. The recirculation loop 56 may have a recirculation tank 65. The purpose of the recirculation tank 65 is to collect residual ozone and separate it from the water. Hence ozone will collect in the upper part of the recirculation tank 65. The ozone destructor 61 is preferably connected to a vent in the upper part of the recirculation tank 65. The recirculation tank 65 may have a pump for providing water to the water treatment unit 52. The pump may be controlled by a level sensor in the recirculation tank 65. The recirculation tank 65 may have a valve for letting in air in the case of vacuum. The recitation tank 64 may have an overflow valve to discharge overflow of water and to protect the ozone destructor 61 from water.

Because of the recirculation loop 56, at least some of the used spraying water used for cleaning container 1, will be used for filling a container 1 with drinking water.

Filling system 50 also comprises suitable piping and control devices such as pumps, sensors, valves and tanks. All components are preferably ozone compatible.

Filling system 50, in particular rinsing and filling device 54, may comprise a tag reader 59, such as an RFID tag reader, for reading the identity tag 5 of container 1. The tag reader 59 may provide an identity of the container 1 to a server 401, as described below. The tag reader 59 may be arranged in relation to the rinsing and filling device 54 so that only containers that are connected to the rinsing and filling device 54 can be read (Fig 5). For example, the tag reader 59 may have a short detection range, such as an NFC tag reader 59 that is used to read an NFC tag. The tag reader 59 may be provided with appropriate control circuitry and a communication interface to be able to communicate an identity and a time point for detecting the tag 5 to server 401. The time point may be communicated as a time stamp.

The dispensing station 80 (Figs. 7-9) may for example be located in the homes of end-users, or at restaurants, bars, schools, hospitals, offices or other places of work, sporting facilities, or other places where it is useful to provide drinking water. Many different designs for the dispensing station 80 are possible. The dispensing station 80 may be suitable to be free standing such as for example on a bar, a table or a bench top or it may be designed to be free standing on a floor or on the ground. The dispensing station 80 may also be integrated into furniture, in particular furniture suitable for kitchens, restaurants, and bars. The dispensing station 80 may also be integrated into a fridge. The dispensing station 80 has a third connector 81 for connecting to the first connector 12 of the container 1. The third connector 81 is preferably arranged such that the container 1 is supported on the dispensing station 80 with the extended nozzle 8 of the container 1 pointing upwards when the container 1 is connected to the dispensing station 80.

The third connector 81 has a water dispensing conduit 82 for dispensing water from the container 1. The water dispensing conduit 82 connects to the second conduit 7 of the container 1. Water is preferably dispensed using gravity flow. The water dispensing conduit 82 preferably has a dispensing valve which an end-user can operate to dispense water from the container. In general, a dispensing valve of dispensing station 80 may be operated in any suitable way such as for example with a push button, or any other suitable means for controlling a dispensing valve. In Fig. 7 the dispensing valve is operated by a handle 91. Connecting the container 1 to the third connector 81 preferably opens the valve of the connector 12 of the container so that it remains open. Dispensing is controlled with the dispensing valve. In some embodiments dispensing from the dispensing station 80 may be controlled with the valve of the connector 12 of the container 1. For example a user may be able to control the connector 81 which opens a spring loaded valve in connector 12.

The third connector 81 has an air conduit 84 for letting in ambient air when dispensing water. The air conduit 84 connects to the first conduit 6 of the container 1. Hence during dispensing, air is let into the container 1 through the extended nozzle 8.

The container 1 may be switched such that a first container 1 that is mechanically connected by the dispensing station 80 is replaced with a second container 1 which then becomes mechanically connected to the dispensing station 80.

The dispensing station 80 may comprise a tag reader 85, which is able to read the tag 5. Looking at Fig. 8, the dispensing station 80 may comprise a network interface 86 for proving data to server 401, in particular data from the tag reader 85. The dispensing station 80 may comprise control circuitry comprising a memory 87, a processor 88, network interface 86 and a bus 90. The control circuitry may be partly arranged on a printed circuit board (PCB). The control circuitry may comprise a timer and a clock. Memory 87 may store software for controlling the tag reader 85 and communication with server 401, storing the identity of the dispensing station 80 and the identity of the container 1. The dispensing station 80 furthermore may further comprise a battery for powering the various electric and electronic components of the dispensing station 80 such as the control circuitry and the tag reader 85. Power may alternatively be provided by a connector and a regular power outlet. Tag reader 85 may read tag 5 at any suitable interval. The read identity may be stored in memory 87 together with a time for reading such as a timestamp.

Figs. 14a and 14b show how a tag reader 59, 85, can be arranged on rinsing and filling device 54 or dispensing station 80 to ensure that only the tag 5 of connected container 1 is read. Two different examples of how the tag reader 59,85 can be arranged in a beverage dispensing station 80 (schematically shown from above) and only detects a beverage container 1 supported by the dispensing station 80 or the rinsing and filling device 54. In Figs 14a and 14b the beverage container 1 rests on dispensing station 80 or rinsing and filling device 54.

For example, the tag reader 59, 85 may be an NFC tag reader that reads at a short distance and in a certain direction, forming a field of detection 62 directed to the site where the beverage container 1 is located on the dispensing station 80, see Fig. 14a. A tag 5 outside the field of detection 62 is not detected by tag reader 85. The tag reader 85, 59 of Fig. 14b has an even shorter range of detection, and only detects the tag 5 when the beverage container 1 is oriented in the correct manner so that the tag 5 faces the tag reader 85. This may be achieved with the use of a directional fit between the beverage container 1 and the dispensing station 80. For example, the correct orientation may be achieved with use of keying between the first connector 12 and the second connector 55 and the first connector 12 and the third connector 81. The arrangements of Figs. 14a and 14b are examples only. Water distribution system 400 (Fig. 10) preferably comprises a plurality of dispensing stations 80, such as two, three, four or more dispensing stations 80 such at least ten or at least 100 dispensing stations 80. Each dispensing station 80 may have a unique identity in system 1. The identity is stored in the dataset in the server 401.

Water distribution system 400 may comprise a plurality of containers 1 that are repeatedly filled with water a rinsing and filling device 54. Each container 1 may have a unique identity stored in the RFID tag. The identities may be stored in the dataset of the server 401.

Server 401 may be able to communicate with tag readers 59, 85 trough network 402. The tag readers 59, 85 may provide the identity of a container 1 to a server 401 when the tag has been read by a tag reader 59, 85. Server 401 may comprise a dataset for storing information about individual containers 1. For example, the dataset may store information about if a certain container 1 is present at a certain dispensing station 80. The dataset may comprise information about if the container has been through a rinsing and filling cycle as detected by tag reader 85, or "flagged" as such. In particular the server 401 may issue a warning message if a container 1 that has not been flagged as rinsed and filled is associated with a dispensing station 80. The server 401 may then output a warning message regarding this to a server user.

The tag readers 59, 85 may communicate with server 401 at any suitable interval, for example according to a predetermined schedule.

Fig. 11 is a flow chart showing a method. The container 1 may first be connected to the rinsing and filling device 54 using first and second connectors 12, 55. This may be done manually by an operator. The method may also comprise a purging step in which any previous content (residual water) of the container 1 is removed, for example by injecting pressurized air into the container 1, for example via first conduit 6. Residual water then exits through second conduit 7. Before a container 1 is filled with water for drinking, the container is cleaned or sanitized. This involves spraying the interior of container 1 with water which preferably is ozonated. A suitable volume for spraying may be from 5% to 30 % of the volume of the container 1. This removes solid waste, such as particles, from the container 1, and kills microorganisms such as bacteria, virus or parasites in particular when the water is ozonated.

The rinsing step 100 may be carried out in any suitable manner, but preferably by injecting water trough first outlet 57 and first conduit 6 of container 1, such that water exits extended nozzle 8 trough opening 10, as described herein.

When non-ozonated water is used for filing the container 1, ozonated water is preferably used for the rinsing step. The rinsing time and the concentration of ozone for the rinsing step may be selected such that microorganisms are destroyed with a high degree of probability. The total contact time for the rinsing step may be from 0.5 seconds to 60 seconds, more preferably from 3 to 20 seconds. The contact time is determined as the time from initiating spraying of water to the end of spraying of water into the container 1.

When the container 1 is filled with ozonated water the contact time of the rinsing step with ozonated water may not be crucial, since the container 1 will be filled with ozonated water for a prolonged time. The purpose of the rinsing step is then mainly to remove particles in container 1.

After the rinsing step, the rinsing water may be removed by purging the container with air. The rinsing step may be single or may be repeated two or three times. The rinsing time indicated includes total rinsing time including all repeated steps, but excluding any purging steps in between.

The second conduit 7 is preferably used for emptying the container after the rinsing step and for any purging step. The first conduit 6 may be used for introducing pressurized air during a purging step. After the final rinsing step, the container 1 is filled with water intended for drinking in step 101. The drinking water is preferably ozonated and may be provided from the same source as the rinsing water. The ozonated water should, however, not be consumed right away. The ozone concentration in the water will however decrease fast due to the low half-life of ozone and the water is safe for consumption within approximately 30 minutes of filling. The exact time depends on the temperature and the concentration of ozone used.

The container may preferably be connected to a filling and rinsing device 54 during steps 100 and 101 as is described with reference to Fig. 5. The filling and rinsing device 54 may automatically carry out a cleaning and filling cycle, when receiving a signal to do so. For example, an operator may manually connect the container 1 to the connector 55 of the rinsing and filling device 54 and then provide a signal to the rinsing and filing device 54 to initiate the cycle.

The rinsing and filling device may scan the tag 5 at the end of the filling step. The identity of the container may then be provided to the server 401 and the container may then be flagged as rinsed and filled by server 401.

The container 1 is then closed for example using a lid or valve in step 102. Alternatively, a self-closing valve closes, for example when the first connector 12 of container 1 is removed from the second connector 55.

If for some reason the container 1 is overfilled any surplus water may leave the container 1 trough opening 10 of extended nozzle 8, and from extended nozzle 8 to the first conduit 6 and the first outlet 57. The surplus water may then be provided to the recirculation loop 56.

In a preferred embodiment ozonated water is the sole agent used to clean or sanitize the container 1. Hence there is no need for other agents such detergents such as sodium hydroxide or potassium hydroxide which is frequently used to clean beer kegs. In a preferred embodiment the container 1 is both filled and rinsed with ozonated water. This provides a safe and simple solution for sanitizing and filling the container 1 with safe drinking water. Using ozonated water in water filling system 50 in general also prevents the growth of microorganisms in the water filling system 50.

Ozonated water may also be used to clean outside of connector 12 in a separate step. For example, by spraying the connector 12 with ozonated water.

Fig. 12 is a flowchart that shows reuse of the container 1. In step 200 the container is rinsed and cleaned as described with reference to Fig. 11 (steps 100-102). In step 201 the container is provided to an end user. This may involve dispensing at least some of the water from the container 1. It may also involve the user attaching the container 1 to a dispensing station 80, for dispensing water from the container 1. It may also involve the tag reader 85 of the dispensing station 80 reading the identification tag 5 of the container 1 and the dispensing station 80 providing the identity of the container 1 to the server 401.

After use, for example when the container 1 is empty, the container 1 may be transported from the end user to the filling system 50 for rinsing and filling in step 202. Hence the container 1 may be reused several times.

Fig. 13 is a flowchart that shows a method for rinsing, filling and dispensing water. The drawings on the left side accompany the steps 300-302. Dashed arrows indicate flow of air whereas full drawn arrows are flow of water.

In step 300 the container 1 is connected to rinsing and filling device 54 and is rinsed by providing water from first outlet 57 of rinsing and filling device 54 so that extended nozzle 8 sprays water on inner surface 9 of upper end 4 of container 1. Water flows along the inner walls 11 of the container, as indicated by the arrows. Air may leave the container 1 trough second conduit 7 and second outlet 58. Rinsing water may then leave the container 1 by second conduit 7, for example by purging with air trough first conduit 6. In step 301 the container 1 is connected to rinsing and filling device 54 and is being filled with water. This is suitably done through second conduit 7 and second outlet 58, while air escapes trough fist conduit 6 and first outlet 57. A predetermined volume of water may be filled. Alternatively, a sensor may sense when the container 1 has reached the desired filling level. Preferably water is not filled above opening 10 of extended nozzle 8. Line 20 indicates the water level in container 1, and in Fig. 13 the container 1 is half full in the process of being filled. Sensor 60 may be used to stop the filling. For example, a sensor 60 may sense when water comes down trough first conduit 6 and first outlet 57. The container 1 is then closed and disconnected from the rinsing and filling device 54.

There may be transport step between step 301 and 302 in which the filled container is transported from the filling system 50 to an end user.

In step 302 the container is connected to a dispensing station 80. A user of the dispensing station 80 may now dispense water from the container 1 by opening two valves, for allowing air to enter through the first conduit 6 via air conduit 84 and for allowing water to flow from second conduit 7 via water dispensing conduit 82. The two valves may be operated simultaneously by one push button, lever or similar in dispensing station 80. The opening 10 of extended nozzle 8 is above the water level 20 so that air can enter container 1 evenly without a bubbling sound and without risk for air lock.

It is understood that some of the present methods and some parts of systems are computer- implemented, using digital computer equipment. The various embodiments and components described herein such as tag readers 59, 85 rinsing and filling device 54, dispensing station 80 server 401 and various components of filing system 50 and communication may use digital computer technology for storing and handling digital information and signals as well as suitable hardware and software, including for example suitable digital processors, digital memories, input means, output means, buses and communications interfaces. A user may be able to make input using for example a keyboard, a mouse or a touch screen. Output may be provided on for example a display. Each of tag readers 59, 85, rinsing and filling device 54, dispensing station 80, ozonation unit 64, and filling system 50 may comprise control circuitry comprising a memory, a processor, a bus and a communication interface.

Data communication in water distribution system 400 may be implemented using suitable networking technologies and protocols, inducing cellular communication such as 3G, 4G and 5G, LoRa, Wi-Fi or Bluetooth, or Ethernet. Data communication can be wireless, or wire bound. Information may be exchanged over a wide area net such as internet. Communication in distribution system 400 such as between dispensing station 80 and server 401 and between tag reader and 59 and server 401 may be carried out using any suitable schedule. Certain methods herein may be implemented with any suitable combination of software and hardware. Any suitable programming language may be used for the software units and methods described.

It is realized that everything which has been described in connection to one embodiment is fully applicable to other embodiments, as compatible. Hence, the invention is not limited to the described embodiments, but can be varied within the scope of the enclosed claims. While the invention has been described with reference to specific exemplary embodiments, the description is in general only intended to illustrate the inventive concept and should not be taken as limiting the scope of the invention. The invention is generally defined by the claims.

Claims

1. A method comprising a) providing a container, where said container having a volume of from 2 liters to 60 liters, b) rinsing the interior of the container with water, c) filling the container with water intended for drinking, and closing the container where the container is made of metal and the water in step b) or step c) has an ozone concentration of from 1 ppm to 10 ppm.

2. The method of claim 1 where both the water used in step a) and b) has an ozone concentration of from 1 ppm to 10 ppm.

3. The method of claim 1 or 2 where the concentration of ozone in the water is from 2 ppm to 5 ppm.

4. The method of any one of claims 1 to 3 where ozonated water is the only agent used to clean or sanitize the container.

5. The method of any one of claims I to 4 comprising the additional step d) of providing the container to a user.

6. The method of claim 5 where the steps b) and c) are carried out at a first time and a second time with the same container, where the container is provided to an end user who dispenses at least some of the water from the container between the first time and the second time.

7. A water filling system (50) comprising a water treatment unit (52) with a water supply (51), an ozonation unit (64) and a water rinsing and filling device (54), the system (50) being arranged to provide water from the water treatment unit (52) to the ozonation unit (64) and from the ozonation unit (64) to the rinsing and filling device (54), the rinsing and filling device (54) comprising a second connector (55) having first and second outlets (57, 58), the second connector (55) being configured to connect to a first connector (12) of a water container (1) such that the first outlet (57) is connected to a first conduit (6) of the container (1) in an airtight manner and the second outlet (58)is connected to a second conduit (7) of the container (1) in an airtight manner, the rinsing and filling device (54) being configured to provide ozonated rinsing water from the first outlet (57) to rinse the interior of the container (1) and configured to collect used rinsing water from the container (1) in the second outlet (58), the water filling system (50) characterized in that the water filling system (50) comprises a recirculation loop (56) for collecting used rinsing water from the second outlet (58) of the rinsing and filling device (54), the recirculation loop (56) being arranged to provide water to the water treatment unit (52), where the recirculation loop (56) has an ozone destructor (61). The water filling system (50) according to claim 7 where the concentration of ozone in the rinsing and filling water is from 1 to 10 ppm. The water filling system (50) of claim 7 or 8 where the water rinsing and filling device (54) is configured to fill a connected container (1) with ozonated water provided from the ozonation unit (64). The water filling system (50) according to any one of claims 7 to 9 where the rinsing and filling device (54) is arranged to fill a connected container (1), and any overfill is collected in the first outlet (6) and provided to the recirculation loop (56). The water filing system (50) according to any one of claims 7 to 10 where at least some water from the recirculation loop (56) is filled into a container (1). The water filing system (50) according to any one of claims 7 to 11 where the ozone destructor (61) is provided on a recirculation tank (65) which is a part of the recirculation loop (56).