WO2021165850A1

WO2021165850A1 - Micro-fibre filter cartridge

Info

Publication number: WO2021165850A1
Application number: PCT/IB2021/051342
Authority: WO
Inventors: James Brian Sirmon
Original assignee: Cleaner Seas Group Limited
Priority date: 2020-02-18
Filing date: 2021-02-17
Publication date: 2021-08-26
Also published as: GB2592196A; GB202002182D0

Abstract

Micro-fibre filter cartridgeA filter cartridge for removing micro-fibres e.g. from a washingmachine has a delivery spool 22 and an uptake spool 21. Aperforated partition wall 23 extends between the spools, and afilter medium 27 in the form of an elongate liquid permeable sheetextends along the partition wall. A drive coupling 33 is associatedwith at least one of said spools, enabling the filter medium to bewound from one spool to the other. The filter cartridge includes aradio frequency signaling device 43 to wirelessly transmit dataenabling the cartridges to be tracked. Sensors 44-48 allow usageto be monitored, including the rate of use of the filter medium aswell as pressure, temperature and opacity of the filtered liquid.

Description

MICRO-FIBRE FILTER CARTRIDGE

TECHNICAL FIELD OF THE INVENTION

This invention relates to a micro-fibre filter cartridge and filter unit.

BACKGROUND

The kinetic action of washing machines abrades fibrous material from clothes, which is flushed out with the waste water. Once redistributed within a large water mass as in a public sewer, these micro-fibres are difficult to remove at water treatment facilities. Hence, plastic micro-fibres from the washing of synthetic clothes often pass into natural water-courses (rivers, and ultimately seas) where they have a prolonged detrimental impact.

One way to address this problem is to use a washing machine outlet filter which removes such entrained micro-fibres. However, the filter medium quickly becomes blocked and requires frequent replacement. This potentially consumes large quantities of natural resources and may itself generate significant amounts of waste plastic which also has a detrimental environmental impact. SUMMARY OF THE INVENTION

The present invention arises from the idea that if such micro-fibre filters employ a filter cartridge which can be used and recycled in an intelligent way the potential impact upon the environment can be minimised.

When viewed from one aspect the present invention proposes a micro-fibre filter cartridge:

- a delivery spool (22) and an uptake spool (21),

- a perforated partition wall (23) extending between said spools,

- a filter medium (27) in the form of an elongate liquid permeable sheet extending between the spools along the perforated partition wall,

- a drive coupling (34) associated with at least one of said spools, wherein the filter cartridge includes a radio frequency signaling device (43) to wirelessly transmit data.

Each cartridge may be allocated a unique identification code which allows the cartridges to be individually tracked throughout their life. Such tracking enables recipients to be identified who do not return cartridges within the normal period so that they can be followed up to ensure that the cartridges are not being used or disposed of in an environmentally damaging way.

In a basic embodiment the radio frequency signaling device could comprise a passive RFID tag. An RFID tag does not contain an internal power source as the power is supplied by a reader. When radio waves from the reader are encountered by a passive RFID tag, a coiled antenna within the tag picks up the electromagnetic energy. The tag draws power from the antenna, energizing the circuits in the tag. Once the tag circuit is energised a unique id number can be transmitted back to the reader so that an individual filter cartridge can be identified and tracked.

In a preferred embodiment the micro-fibre filter cartridge incorporates a power source (42) such as a battery or supercapacitor. In a preferred embodiment the radio frequency signaling device (43) is powered by the power source (42).

In a preferred embodiment the radio frequency signaling device (43) may be a data processing and communication device, e.g. a Bluetooth, wifi or IOT data processing and communication device.

In a preferred embodiment the micro-fibre filter cartridge incorporates a sensor (44, 48) to monitor movement of an associated uptake or delivery spool (21, 22).

In a preferred embodiment the micro-fibre filter cartridge incorporates an opacity sensor (45) to monitor the opacity of liquid when the filter cartridge is received in a filter chamber (2).

In a preferred embodiment the micro-fibre filter cartridge incorporates a back-pressure sensor (46) to monitor liquid pressure when the filter cartridge is received in a filter chamber

(2).

In a preferred embodiment the micro-fibre filter cartridge incorporates a temperature sensor (47) to monitor the temperature of liquid when the filter cartridge is received in a filter chamber (2).

The invention also provides a filter unit containing the micro-fibre filter cartridge.

BRIEF DESCRIPTION OF THE DRAWINGS

The following description and the accompanying drawings referred to therein are included by way of non-limiting example in order to illustrate how the invention may be put into practice. In the drawings:

Figure 1 is a general view of a filter unit with its lid removed to show an internal filter cartridge;

Figure 2 is an end view of the filter unit looking from the left in Fig. 1;

Figure 3 is a plan view of the filter unit;

Figure 4 is a rear view of a filter cartridge which can be used in such a filter unit;

Figure 5 is a bottom view of the filter cartridge.

DETAILED DESCRIPTION OF THE DRAWINGS

Referring firstly to Fig. 1, the micro-fibre filter unit shown in the drawing is particularly suitable to be connected in the water drainage outlet hose of a washing machine, e.g. in a cupboard under a sink. The filter comprises a generally rectangular housing 1 which contains a filter chamber 2 provided with an inlet 3 for unfiltered liquid and an outlet 4 for filtered liquid. (See Fig. 2 also.) Opposite sides of the housing are formed with side chambers 5 and 6 to receive and locate a filter cartridge 7 which extends across the filter chamber 2 between the two side chambers, as shown. A separate lid (not shown) is provided to seal the filter chamber 2 in use. In some embodiments the filter unit may include a suitable mechanical ejection mechanism to eject the filter cartridge 7 from the filter chamber 2, but such a mechanism is omitted for clarity.

Turning to Fig. 3, the filter cartridge 7 which is installed in the filter unit has a casing 20 which contains an uptake spool 21 and a delivery spool 22 rotatably mounted at opposite ends of the casing. Part of the casing 20 extends between the two spools forming a perforated double-layer partition wall 23, which is also seen in Fig. 1. In the filter cartridge which is shown in Fig.s 1 and 3 the partition wall 23 has a planar portion 24 with transverse channel sections 25 and 26 which both extend to the same side of the planar portion 24. The channel sections 25 and 26 increase the area of the partition wall which is exposed to liquid flowing through the filter chamber 2, but the partition wall 23 could also be straight. A filter medium 27 in the form of an elongate liquid permeable sheet of paper, cotton or other porous material, extends between the spools 21 and 22 traveling along the perforated partition wall 23 between its two layers. The filter medium preferably has a filter mesh or aperture size of 5 pm to 20 pm, although smaller or larger sizes can be used depending on the size of the micro-fibres being targeted. A 5 pm to 20 pm filter mesh size is suitable to remove at least 90% of all synthetic micro-fibres. In a new cartridge most of the filter medium is wound on the delivery spool 22, but the filter medium medium is progressively wound onto the uptake spool 21 by mans of a mechanical indexing mechanism, as described below.

The filter cartridge 7 is dimensioned to fit snugly into the filter chamber 2 with the two spools 21 and 22 located in the side chambers 5 and 6. The partition wall 23 and filter medium 27 extend across the chamber 2 passing through slots 8 and 9 in the side chambers 5 and 6. When the cartridge 7 is installed in the filter unit the filter medium divides the interior of the filter chamber 2 into an inlet chamber 2A and an outlet chamber 2B on opposite sides of the perforated partition wall 23. The two chambers 2A and 2B respectively connect with the water inlet 3 and the water outlet 4. The inlet chamber 2B contains an impeller 30 to drive a mechanical energy storage unit 31 which is drivably and releasably engaged with the uptake spool 21, e.g. via a splined or friction drive arrangement. During normal flow from inlet 3 to outlet 4 the impeller 30 winds up the energy storage unit 31 which in turn drives the uptake spool 21. The filter medium is therefore wound into the uptake spool, drawing clean sections of the filter medium across the partition wall 23. The impeller 30 also carries a magnet which co-operates with a hall effect sensor 32 to allow the flow rate through the inlet chamber 2B to be measured.

Turning Fig.s 4 and 5, for convenience of illustration these figures show the perforated partition wall 23 schematically without the perforations or the channel sections 25 and 26. As can be seen in the bottom view, the spools 21 and 22 have radial fins 33 and 34 respectively, which in the case of the uptake spool 21 may form part of a drive coupling with the energy storage unit 31. The filter cartridge 7 includes two printed circuit boards, shown separately in Fig. 4, namely a main board 40 and a second board 41, which are both electrically insulated from the liquid within the filter chamber 2, e.g. by use of a suitable potting material. The two boards 40 and 41 are mounted at opposite ends of the perforated partition wall 23. In this embodiment a main board 40 is associated with the delivery spool 22 and the second board 41 is associated with the uptake spool 21, but these could be reversed. The two boards are electrically connected together by suitable insulated electrical conductors (not shown). The main board 40 may also be connected to the hall effect sensor 32 via a releasable electrical connection. Alternatively, with a minor modification to the cartridge casing the sensor 32 could be incorporated into the filter cartridge 7.

The main board 40 carries a power source 42 such as a replaceable or rechargeable battery or a capacitor with a high capacitance value (known as a supercapacitor). Board 40 also carries a radio frequency communication device 43 such as a Bluetooth CPU, a wifi or IOT (Internet of Things) data processing and communication device with an appropriate chipset, along with various sensors 44-47. Sensor 44 is an optical sensor which is located to optically monitor the associated delivery spool 22 by sensing movement of the fins 34. Sensor 45 is an opacity sensor which monitors a light signal emitted from the second board 41 (see below). A back-pressure sensor 46 monitors the liquid pressure within the inlet chamber 2A, and a temperature sensor 47 monitors the temperature of liquid within the chamber.

The second board 41 carries a further optical sensor 48 which is located to optically monitor the associated uptake spool 21 by sensing movement of the fins 33. In addition, an opacity emitter 49 emits a light signal which is directed towards the optical sensor 45 on the main board 40. Both sensors 48 and 49 communicate with the main board 40 via the aforementioned wired connection.

The sensors 44-48 collect various information about the working conditions of the filter cartridge which is fed to the radio frequency communication and data processing device 43 which collects and stores the information. The communication device 43 enables the stored information to be transmitted in real time to various physically unconnected devices such as smart phones, wifi hubs or other data collection devices.

An important feature of the filter unit is that the cartridges are not discarded after use but are mailed to a recycling unit where the filter medium is removed and disposed of in an environmentally responsible manner. Each cartridge is allocated a unique electronically stored identification code which, at a basic level, allows the cartridges to be individually tracked throughout their life for stock control purposes. Such tracking enables recipients to be identified who habitually do not return cartridges within a required period so that they can be followed up to ensure that the cartridges are not being disposed of in an environmentally damaging way or washed in a sink and returned to service, which is also damaging. The stored data can also be gathered by the recycling centre to obtain useful information about the operating conditions of the filter unit. The power source 42 for the electronic parts of the filter cartridge is recharged each time the cartridge is returned for recycling.

By way of example, the information collected by the various sensors 32 and 44-48 can typically be used as follows.

Wash temperature sensor 47: The data from this sensor can be used to monitor the users washing habits. This can be used to advise the user to wash at lower temperatures to reduce fibre shedding, for example.

Water flow rate sensor 32: The rate of flow through the filter cartridge is monitored by the hall effect sensor 32. Flow data can be used to monitor users washing habits and advise accordingly.

Back pressure sensor 46: This data can be used to trigger the unit to wind on new filter medium and/or warn of any blockages which result in a rapid rise in the back pressure.

Filter roll usage rate (sensors 44 and 48): This data can be used to advise the user how much filter medium is being used per wash and advise the user on how to be more efficient with the system.

Filter cartridge jam detection (sensors 44 and 48): This data can be used to detect when the filter medium is not being wound on and either trigger the unit to attempt to wind on the filter medium and/or send out a filter jam warning.

Overdosing powder sensor 45: The filter cartridge should typically have an in-situ service life of around 6 months. One of the biggest factors which causes the system to use large volumes of filter medium per wash is the amount of washing powder or liquid detergent used per wash. The sensor 45 monitors the opacity of the liquid in the inlet chamber 2A enabling the processing device 43 to determine whether the amount of washing powder/liquid used per wash is significantly greater than is required. If so, the communication device can advise the user accordingly to ensure that the amount of detergents entering the environment is minimised. The information obtained from the sensors can be transmitted to a users smart phone which is provided with an app which will be linked to a customer internet server account. The following general information about the status of the filter unit can thus be made readily and instantly available to the user:

• Filter Cartridge washes remaining

• Filter jam

• Usage rate

• Blockage alarm

• Wash temperature

• Last wash date and time

• Number of washes per week/month

• Detergent dosing level

• Washing detergent/temp/program setting advice

• Overall user green score

The information listed above would all be viewable on a customer app which can run on Android or Mac or Windows systems. The user will also be able to log in to a website using an account name a password to also see all of the collected data. This information can be sent back to a recycling organisation server for storage and analysis. The user app can also be used to configure and setup the filter for the profile of the customer. These options can include:

Washing machine type (Back pressure setting)

Family profile (Usage rate)

Preferred washing temperature

Main washing type

Detergent dosing rate

GPS Location (Water type, Local water supplier)

On filter units installed with mains powered washing machines there could be an option to wind on the filter cartridge by means of an electric motor, auto eject/auto drain/refill then auto retract the filter cartridge, and give a visual indication of the filter status.

The filter cartridge should typically have an in-situ service life of around 6 months, so as not to require frequent recharging or other maintenance. To summarise the main features of the filter:

• The filter cartridge is capable of removing at least 90% of all synthetic micro-fibres.

• The filter cartridge is a mailable item to enable central processing and exchange of filters.

• Filter medium movement is self-powered e.g. by water flow.

• The filter system can be retro-fitted to existing washing machines. • All components of the filter can have high environmental credentials through use of recycled plastics etc.

Although an external micro-fibre filter has been described herein for purposes of example the filter could equally be incorporated into washing machines at manufacture. When the filter is intended to be installed in a washing machine the drainage chamber may not be necessary since an electrical signal from the door interlock of the washing machine can be used to operate a solenoid which prevents the filter from being opened while the machine is in use. Furthermore, the cartridge ejection mechanism itself could be operated by a solenoid or electric servo-motor instead of a manual lever, which is again linked to the door interlock to prevent the cartridge from being ejected while the machine is operating. It will also be appreciated that since an electrical supply is readily available inside a washing machine the filter medium in the filter cartridge can be indexed by an electric motor or solenoid controlled by water back-pressure.

The development of the micro-fibre filter has been driven by a desire to make the unit easy and convenient to use, reducing the barriers to actual deployment and the filter's environmental benefit. Central filter processing would prevent users cleaning the filters themselves and the plastic micro-fibres ending up in landfill where they are not suitably contained within a closed loop recycling system and still have a high likelihood of being carried into a water course. Whilst the above description places emphasis on the areas which are believed to be new and addresses specific problems which have been identified, it is intended that the features disclosed herein may be used in any combination which is capable of providing a new and useful advance in the art.

Claims

1. A micro-fibre filter cartridge:

- a delivery spool (22) and an uptake spool (21),

- a perforated partition wall (23) extending between said spools,

- a drive coupling (33) associated with at least one of said spools, wherein the filter cartridge includes a radio frequency signaling device (43) to wirelessly transmit data.

2. A micro-fibre filter cartridge according to claim 1 which incorporates a power source (42) such as a battery or supercapacitor.

3. A micro-fibre filter cartridge according to claim 2 wherein the radio frequency signaling device (43) is powered by the power source (42).

4. A micro-fibre filter cartridge according to any preceding claim wherein the radio frequency signaling device (43) is a data processing and communication device.

5. A micro-fibre filter cartridge according to claim 4 wherein the radio frequency signaling device (43) is a Bluetooth, wifi or IOT data processing and communication device.

6. A micro-fibre filter cartridge according to any preceding claim which incorporates a sensor (44, 48) to monitor movement of an associated uptake or delivery spool (21, 22).

7. A micro-fibre filter cartridge according to any preceding claim which incorporates an opacity sensor (45) to monitor the opacity of liquid when the filter cartridge is received in a filter chamber (2).

8. A micro-fibre filter cartridge according to any preceding claim which incorporates a back-pressure sensor (46) to monitor liquid pressure when the filter cartridge is received in a filter chamber (2).

9. A micro-fibre filter cartridge according to any preceding claim which incorporates a temperature sensor (47) to monitor the temperature of liquid when the filter cartridge is received in a filter chamber (2).

10. A filter unit containing a micro-fibre filter cartridge according to any preceding claim.