Pressure Consuming Regenerative Filter

Abstract

The present invention relates to preventing microplastics from entering the environment. In particular, the present invention is directed to regenerating the pressure consumption of a filter for removing microplastics from effluent. A separator for separating microplastics from effluent is provided, the separator comprising a chamber having an inlet and an outlet, a sieve structure forming a permeable barrier between the inlet and the outlet for filtering the effluent, thus having an inlet side for unfiltered effluent and an outlet side for filtered effluent, the separator further comprising a filter pressure regeneration device for removing filtered material from the sieve structure, the filter pressure regeneration device comprising a conduit and a nozzle assembly having at least one washing nozzle oriented toward the outlet side of the sieve structure to remove filtered material from the inlet side of the sieve structure.

Description

[Technical field]

[0001] The present invention relates to preventing microplastics from entering the environment. In particular, the present invention is directed to removing microplastics in effluent from any source, but is particularly directed to regenerating the pressure consumption of filters for removing microfibers from washing machine wastewater. [Background technology]

[0002] Microfibers are the most abundant form of microplastic pollution in rivers and oceans. Due to their microscopic scale, microfibers are eaten by organisms at all levels of the food chain, from plankton to top predators. When ingested, plastics can reduce feeding efficiency (false satiety), damage the animal's intestines, and transfer harmful additives such as PCBs, pesticides, and flame retardants to the animals that consume them. Plastics consumed by animals lower in the food chain also affect their predators, which consume a lot of contaminated food every day. The pervasiveness of microfibers in the food chain has understandably raised concerns about their transfer to humans, and contamination has been observed in crustacean, mollusc, and fish species that are destined for human consumption.

[0003] Unlike microbeads, which are easily eliminated from cosmetics and cleaning products, microfibers are formed by damage to clothing. One third of all microplastics in the ocean come from the washing of synthetic fibers. Synthetic fabrics, derived from petrochemicals, make up 65% of all textiles. Wear and tear caused by abrasive forces in washing machines leads to the fragmentation of synthetic fibers, forming hundreds of thousands of microfibers less than 5 mm long, which leak into the ocean from homes and drainage networks.

[0004] The profound impact of microplastics on marine ecosystems is beginning to be understood. A 2019 study published in the journal Science of the Total Environment found that 49% of 150 fish samples from the Northeast Atlantic contained microplastics, with evidence that this causes harm to the brain, gills, and back muscles. These microplastics are also passed on to people who consume fish, at a rate of 518-3078 microplastic items per person per year.

[0005] The impacts are seen not only on fish stocks but also on algae, the building blocks of life. A 2015 study published in the journal Aquatic Toxicology demonstrated that high concentrations of polystyrene particles reduced algae growth by up to 45%. This is of concern as microalgae are one of the world's largest producers of oxygen on the planet.

[0006] Wastewater treatment plants cannot remove the millions of fibers that pass through them every day. Currently, secondary levels of water treatment remove about 98% of the microplastics that pass through them. However, the small percentage that leaks still amounts to tens of millions of fibers per treatment run per day.

[0007] Additionally, wastewater treatment plants produce "sewage sludge" and plastic microfibers are found in the discharge when the sludge is spread on agricultural land or released into the natural environment, thus allowing the microfibers to enter the food chain, waste-to-energy (which breaks down the fibers but can release harmful gases), or be discharged into rivers or oceans.

[0008] Solutions have been developed to capture microfibers generated in domestic washing machines by filtering the effluent from the washing machine.

[0009] A typical front-loading domestic washing machine is shown in schematic form in FIG. 1. The washing machine 100 includes a rotatable sealed drum unit 101 for receiving the clothes to be washed. The drum unit 101 has a perforated cylindrical rotatable drum mounted inside a stationary waterproof shroud. Clean water is pumped into the drum 101 under mains pressure, typically 1-5 bar, via a cold or hot water inlet 102 connected to the mains. Water entering the drum 101 is managed by an electronic valve, under the control of a CPU 104. The inlet 102 is connected to a drawer 105 where the user can add liquid or powder detergent. The drawer has an outlet leading to the drum unit 101. The drum unit may include a heater, under the control of the CPU, to heat the water to the desired wash temperature, typically 90 degrees Celsius. The drum is rotatable by an electric motor 106, under the control of the CPU 104, at a speed typically between 5 and 1600 rpm. The drum unit can be emptied via a drain pump 108, which is controlled by the CPU. The drain pump is rated at a given power to generate a known pressure at its output. The drain pump connects to a domestic or industrial drain and ultimately to an outlet 109 which is connected to a wastewater network.

[0010] A typical top-loading machine has a vertical drum axis, but otherwise shares many of the characteristics of a front-loading machine.

[0011] In use, dirty laundry is placed into the drum and a wash cycle is started by the user. The CPU allows cold water to flow through the drawer to mix with the detergent and then into the drum where the water is heated. The combined water, detergent and laundry are agitated by spinning the drum. During this process, dirt and grease are released into the water and fibers are also released from the clothes. If the clothes are synthetic, microfibers are typically released as the clothes rub against each other. The resulting effluent at the end of the wash cycle is a mixture of debris, dirt, grease and microfibers along with potentially larger objects such as coins or fingernails that are left on the clothes. This effluent is then drained and pumped out of the drum at a typical rate of 3-8 gallons per minute. A second or third rinse cycle with clean water may be performed, resulting in an effluent with a lower concentration of contaminants. The drain rate of the washing machine is influenced by the water level in the drum, the height of the outlet point and if a filter is connected to the outlet.

[0012] Current washing machine filters are designed to stop pennies and buttons that destroy washing machine pumps. These filters often have open apertures of 7-14 mm, which are too large to effectively capture large amounts of microfibers. The filtration required to stop microfibers is typically less than 400 micrometers (um). Reducing the aperture size removes a higher percentage of the fibers in the water.

[0013] It is known to provide mesh filters that stop the problem at the source. However, mesh filters quickly become clogged and when this happens, their effectiveness is significantly reduced. This can increase pressure and reduce flow rate, leading to damage to the pump and slowing down the wash cycle.

[0014] In a typical wash, the highest concentration of microfibers ranges from 5mm to 50um, but shorter microfibers exist and these are still harmful in the environment. If it is required to remove 99% of all sizes of microfibers up to 50um in length, a mesh with 25um apertures could theoretically achieve this. However, in practice, such a mesh placed directly in the effluent stream will clog almost immediately and the filter will become inoperable. This will cause an increase in pressure consumption at the outlet and may damage the pump.

[0015] A conventional separator or filter arrangement is shown in FIG. 2a. An inlet 201 directs effluent into a filter housing 202 in which a sieve structure 203 is supported. The sieve structure can be a mesh or other perforated material, with the mesh opening size selected to capture particles of the required size. The filtered effluent passes through the sieve structure 203 to an outlet 204. Filtered waste accumulates on the side of the sieve structure called the unfiltered side, while the outlet side of the sieve structure is called the filtered side. Filter efficiency is its effectiveness in removing debris of a given size range while maintaining an acceptable flow rate, and is closely related to the pressure consumption of the filter. The sieve structure shown in FIG. 2a quickly becomes clogged by filtered debris, which results in its pressure consumption increasing.

[0016] In use, as effluent fills the chamber, particles are filtered out and remain attached to the outside of the mesh, increasing the power consumption of the filter as the mesh begins to clog.

[0017] Curve 1 in Figure 2b is a measure of the effectiveness of the arrangement shown in Figure 2a, assuming a constant contamination level and a constant wastewater flow rate. The y-axis represents the fluid pressure P at the inlet 201, which can be seen to increase gradually and then exponentially as the mesh becomes clogged with filtrate.

[0018] In reality, the flow of effluent from the washing machine is not constant over time, since a limited amount of water is used in each wash cycle. Curve 2 in Figure 2b shows how the inlet pressure changes over time when the flow of effluent stops, drains through the device, and then starts again. A reduction in pressure is seen as the flow stops and the debris previously held against the mesh by the pressure of the flow is dislodged, exposing pores that allow the fluid to flow again until it is blocked off again in the next cycle. Curve 2 demonstrates that the pressure consumption required by the conventional device increases through use, so that the inlet pressure required to filter the effluent eventually becomes higher than the pump can provide.

[0019] The device must be opened and the mesh manually cleaned to return its pressure consumption to a level at which the device will operate effectively, i.e. to regenerate its pressure consumption. This is a tedious and laborious process. In some filter types, regeneration is not possible, for example if the filter is a cartridge type filter. These filters require the user to periodically remove and replace the filter, which leads to a poor user experience and waste from consumable parts. Thus, the present invention seeks to overcome the challenge of effectively regenerating the pressure consumption of mesh filters used to separate microplastics from effluent streams.

[0020] Figure 3 shows an alternative arrangement in which the effluent inlet 301 is located at one end of a channel 302 and a sieve structure 303 forms the wall of the channel 302. In this way, the incoming effluent pushes the filtered waste towards the other end of the channel. The sieve structure does not clog as quickly as the one shown in Figure 2a, but the pressure consumption increases until the filtering action stops. It is therefore an object of the present invention to regenerate the pressure consumption of the microplastic separator unit. Summary of the Invention

[0021] In one embodiment, a separator for separating solid material, including microplastics, from a fluid, such as an effluent, is provided, the separator comprising a chamber having an inlet and an outlet, a sieve structure forming a permeable barrier between the inlet and the outlet for filtering the fluid, thus having an inlet side for unfiltered fluid and an outlet side for filtered fluid, the separator further comprising a filter pressure recovery device for removing filtered material from the sieve structure, the filter pressure recovery device comprising a conduit and a nozzle assembly having at least one washing nozzle for directing a washing fluid towards the outlet side of the sieve structure to remove filtered material from the inlet side of the sieve structure, the chamber comprising a chamber having an inlet and an outlet, the chamber having an inlet and an outlet, the sieve structure forming a permeable barrier between the inlet and the outlet for filtering the fluid, the sieve structure further comprising a filter pressure recovery device for removing filtered material from the sieve structure, the filter pressure recovery device comprising a conduit and a nozzle assembly having at least one washing nozzle for directing a washing fluid towards the outlet side of the sieve structure to remove filtered material from the inlet side of the sieve structure, the chamber comprising a chamber having an inlet and an outlet, the chamber having an inlet and an outlet, the chamber having an outlet and an outlet, the chamber having an inlet and an outlet, the sieve structure forming a permeable barrier between the inlet and the ... The separator includes a channel formed from the walls of the chamber and a sieve structure, the inlet may be located at one end of the channel, so that in use, fluid flows through the channel and material removed by the washing fluid from the washing nozzles can be swept away from the inlet towards the other end of the channel by the movement of the fluid, the sieve structure has a circular cross section and is located within the chamber, the inlet is arranged to direct the fluid into the chamber tangentially onto the sieve structure, and a wall is provided on one side of the inlet, so that the fluid is guided through the channel in a circumferential direction around the sieve structure, so that the filtered material removed by the washing fluid from the washing nozzles is swept around the chamber by the flow of fluid and accumulates on the side of the wall away from the inlet. The advantages of this arrangement, where the filtered solid material travels along the channel, are better use of space, increased solid material collection capacity, and ease of handling of the filtered solids. Although the description herein is directed to filtering microplastics from effluent, the separator may be applied to separate any solid material from any fluid.

[0022] A trap with an opening into the subchamber at the base of the channel can be provided to collect the accumulating filtered material.

[0023] The nozzle assembly may include a plurality of cleaning nozzles that are rotatable about a central axis of the sieve structure.

[0024] The wash nozzles may be disposed opposite one another and may be mounted to a central feed tube.

[0025] The nozzle assembly may be rotated by a motor.

[0026] The nozzle assembly may be rotated by a propulsion nozzle disposed to direct the flow of fluid. The nozzle may be disposed off-center from the central axis to provide the propulsion force or may have a vector tangential to the circumference of the sieve structure.

[0027] The cleaning nozzles may be arranged to direct cleaning fluid perpendicular to the sieve structure.

[0028] The wash nozzles may be arranged helically around the central feed tube.

[0029] The chamber may have a closed top and bottom.

[0030] A pump may be provided in fluid communication with the outlet of the chamber.

[0031] The pump may be a water pump arranged to drain the separator.

[0032] A pump may be disposed to recirculate the filtered fluid to a conduit of the filter pressure regeneration device.

[0033] A second pump may be disposed to recirculate the filtered fluid to the conduit of the filter pressure regeneration device.

[0034] The separator may further include an air pump located between the pump and the filter pressure regeneration device to introduce air into the conduit and to drain the separator.

[0035] A fluid detector may be provided and the filter pressure regeneration device may be arranged to be activated according to an output from the fluid detector.

[0036] A reservoir may be provided below the chamber and the fluid detector may be located within the reservoir. The fluid detector may also be located where a conduit feeding an inlet to the filter, an outlet to the filter, or a bypass conduit may be located. Some detector types, such as differential pressure sensors, may use multiple locations to provide a differential measurement, while other detector types may only require a single location.

[0037] In some embodiments, it may be advantageous to use multiple sensing options to provide a higher level of intelligence to the system.

[0038] The fluid detector may be a float switch, a capacitive sensor, an ultrasonic sensor, an optical detector, a differential pressure sensor, or a pressure sensor.

[0039] A bypass conduit may be provided between the inlet and outlet to provide an alternative path for fluid if fluid flow through the filter chamber is interrupted.

[0040] The bypass conduit may include a pressure activated valve.

[0041] The nozzle assembly may include a nozzle arranged to direct a flow of fluid toward a rotatable body, the body arranged to rotate under the force of the fluid flow and to project the fluid outwardly toward the sieve structure.

[0042] In one embodiment, the washing machine includes a separator of the type described above.

[0043] In one embodiment, a method of operating a separator of the type described above is provided, comprising the steps of filtering a fluid through a sieve structure, washing the filtered side of the sieve structure with a jet of fluid from a nozzle to clean accumulated debris from the unfiltered side of the sieve structure and regenerate pressure consumption of the separator.

[0044] The method may include a further step of sweeping a nozzle across the filtered side of the sieve structure.

Brief Description of the Drawings

[0045] [Figure 1] Shows a typical household washing machine. [Figure 2a] Shows a conventional separator. [Figure 2b] It is a graph showing the effectiveness of different types of filter assemblies. [Diagram 3] Shows a cross-section of a conventional filter assembly. [Figure 4] Shows a cross-sectional view of one embodiment having a single nozzle for regenerating the pressure consumption of the filter. [Diagram 5] Shows a cross-sectional view of one embodiment having an array of nozzles for regenerating the pressure consumption of the filter. [Figure 6a] Shows one embodiment having a cylindrical sieve structure and an array of fixed cleaning nozzles. [Figure 6b] Shows another view of the embodiment of 6a. [Figure 7a] Shows one embodiment having a rotating cleaning nozzle. [Figure 7b] Shows a detailed view of waste material discharged from the unfiltered side of the sieve structure by spraying a jet of fluid from the filtered side of the sieve structure. [Figure 7c] Shows a detailed view of water pellets being discharged from the nozzle. [Figure 8a] Shows an alternative arrangement of the cleaning nozzles. [Figure 8b] Shows an alternative arrangement of the cleaning nozzles. [Figure 9a] Shows an alternative arrangement of the cleaning nozzles. [Figure 9b] Shows an alternative arrangement of the cleaning nozzles. [Figure 10a] Shows a propulsion nozzle assembly. [Figure 10b] Shows the propulsion nozzle assembly in operation. [Figure 11a]FIG. 2 shows a perspective view of one embodiment of a separator. [Figure 11b] FIG. 2 shows a cross-sectional view of one embodiment of a separator. [Figure 11c] FIG. 2 shows a cross-sectional view of one embodiment of a separator. [Figure 11d] FIG. 2 shows a cross-sectional view of one embodiment of a separator. [Figure 12] FIG. 2 shows a cross-sectional view of one embodiment of a separator having a recirculation pump for recirculating filtered effluent as a wash fluid. [Figure 13a] FIG. 1 shows a cross-sectional view of one embodiment of a separator having a combined recirculation and drain pump for recirculating filtered effluent as a wash fluid and draining the separator. [Figure 13b] 1 shows an alternative arrangement of pumps and conduits; [Figure 14a] FIG. 11 is a diagram of different mesh heights. [Figure 14b] FIG. 11 is a diagram of different mesh heights. [Figure 15a] FIG. 13 illustrates different filter chamber diameters. [Figure 15b] FIG. 13 illustrates different filter chamber diameters. [Figure 16] FIG. 2 is a cross-sectional view of a filter chamber having a flap. [Figure 17] FIG. 2 is a cross-sectional view of a filter chamber having a restriction. [Figure 18] FIG. 2 is a cross-sectional view of a filter chamber having a direct drive nozzle assembly. [Figure 19A] FIG. 2 is a perspective view of a nozzle assembly having a slot. [Figure 19B] FIG. 1 is a perspective view of a nozzle assembly having a slot and only a single arm. [Figure 20a] FIG. 1 is a perspective view of a filter assembly having a fixed nozzle and a rotating mesh. [Figure 20b] FIG. 1 is a perspective view of a filter assembly having a rotating nozzle on the exterior of a sieve structure. [Figure 20c]FIG. 2 is a perspective view of a filter assembly having a nozzle assembly with a rotatable plate. [Figure 21a] FIG. 2 is a perspective view of one embodiment of a separator unit. [Figure 21b] FIG. 21b is a perspective view of the embodiment of FIG. 21a with the jug removed. [Figure 22a] FIG. 21b is a cross-sectional view of the embodiment of FIG. 21a. [Figure 22b] FIG. 21b is a perspective view of the pump and duct assembly of the embodiment of FIG. 21a. [Diagram 23] FIG. 21b is a perspective view of a portion of the filter assembly of the embodiment of FIG. 21a. [Figure 24] FIG. 21b is a perspective view of the nozzle assembly of the embodiment of FIG. 21a. [Diagram 25] FIG. 21b is a top view of the jug of FIG. 21b with the cap removed. [Figure 26] FIG. 21b is a diagram of a printed circuit board in place within the components of the embodiment of FIG. 21a. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0046] Although the following description focuses on washing machines for clothes, it should be understood that the teachings herein are not limited to use in washing machines, as the teachings herein are similarly suitable for other processing appliances, such as, but not limited to, dryers, such as combined washer-dryers, tumble dryers, dyeing machines, cutting machines, recycling machines, dry cleaning machines, and the like. The washing machines or other processing appliances may be domestic or commercial. The teachings herein may also be used in other industries where particulates may be generated as a result of the processing of items. Thus, references herein to washing machines should be understood to include any similar appliances of the type contemplated herein.

[0047] The separators described herein can be installed within the appliance itself during manufacture, as shown in FIG. 23a, or can be retrofitted externally to the washing machine or other appliance, as shown in FIG. 23b.

[0048] The separator system 2800 described above may be installed in a washing machine as shown in Figure 28a. Waste from the washing machine drum connects to an inlet 2807 of the separator 2800 and the outlet of the separator connects to a waste outlet 2809.

[0049] A supply of fresh water 2806 to the regenerator is shown, but this supply is not necessary if a recirculation system is used. The separator system 2808 can be located outside the washing machine and connected to the waste water outlet of the washing machine, as shown in FIG. 28b. An inlet 2809 feeds the effluent into the separator 2808, and an outlet 2810 feeds the waste water pipe 2805. The embodiment shown is fitted with a drain pump to allow installation below the dotted water level line in the figure, i.e., the top of the waste water pipe. The embodiment shown also has a recirculation system, so a separate supply of fresh water is not required. The device can be connected to a power source (not shown) to operate the pump. It will be further understood that the teachings herein are suitable for any application in which microplastics, including microfibers, need to be removed from any effluent, including wastewater, in which such materials may be entrained. For example, to capture solid components entrained in runoff from roadside gutters, as described in more detail below.

[0050] It is noted that wastewater from washing machines and other applications contains a wide variety of compounds, including microplastics. The filter is particularly well suited to trapping microplastics, but due to the environment in which it operates, the system is also robust against the harsh and diverse compounds it comes into contact with.

[0051] Effluent is understood to include wastewater from the aforementioned sources. Effluent can also include wastewater from wastewater treatment plants. Effluent contains entrained dirt, detergents, and micro-pollutants including microplastics, including microfibers.

[0052] FIG. 4 shows an embodiment of the present invention for separating microplastics from effluent, regenerating the pressure consumption of the filter, comprising an effluent inlet 401 feeding a channel bounded by a filter housing 402 and a sieve structure 403. The filtered effluent leaves the separator via an outlet 404. A washing nozzle 405 is provided arranged to direct a washing jet of washing fluid to the filtered side of the sieve structure 403. The washing nozzle 405 is connected to a source of washing fluid by a conduit 406. The washing nozzle is periodically operated to remove the material to be filtered from the unfiltered side of the sieve structure, which regenerates the pressure consumption and thus allows more effluent to be filtered. Once the waste material is removed, the flow of effluent carries it further away from the inlet towards the far end of the channel.

[0053] The pressure regeneration effect can be enhanced by a filter pressure regeneration system. This system comprises a nozzle assembly with an array of washing nozzles. Figure 5 shows an embodiment for separating microplastics from effluent, comprising a filter housing 502 and an effluent inlet 501 feeding a channel bounded by a sieve structure 503. The filtered effluent leaves the separator via an outlet 504. The nozzle assembly 505 comprises a number of washing jets 506a, b, c, d, e to which washing fluid is fed by a conduit 507. The washing jets are periodically operated to remove the material to be filtered from the unfiltered side of the sieve structure, which regenerates the pressure consumption and thus allows more effluent to be filtered. Once the waste material is removed, the effluent flow carries it further away from the inlet towards the far end of the channel.

[0054] Figures 6a and 6b show an embodiment of the present invention for separating microplastics from effluent that regenerates the pressure consumption of the filter to or near the level when the filter was new. A cylindrical chamber 601 is provided with an inlet 602 and a central cylindrical sieving structure 603. A wall 604 is provided on one side of the inlet, which acts as a baffle that allows the effluent to flow only in one direction as it enters the chamber and allows the filtered debris to collect in a specific location within the chamber. The internal wall of the chamber 601, the external wall of the sieving structure 603, and the wall 604 define a channel through which the unfiltered effluent can flow to the other side of the wall 604 and accumulate there. An aperture 605 is provided through which the filtered material can pass and be captured. A filter pressure regeneration system is provided that includes a washing fluid conduit 606 that projects radially outward from the conduit 1206 and delivers washing fluid to an array of washing nozzles 607 arranged to direct washing fluid vertically at the filtered side of the sieve structure 603 to remove material that has accumulated on the unfiltered side of the sieve structure. As material is removed, it is swept by the effluent flow toward the end of the channel, through apertures 605, and into a trap. Although a trap is desirable, the embodiment can function without it. The jet of washing fluid can be operated continuously or periodically. The washing fluid is pressurized and forced through the washing nozzle such that the jet of washing fluid emitted from the washing nozzle has sufficient force to dislodge the material against the flow of the effluent fluid components through the sieve structure. In one embodiment, if the filter is in direct communication with the washing machine, it may be advantageous to temporarily stop the drain of the washing machine to allow the mesh to be washed without pressure from the wastewater drain. The wash fluid may be clean mains water and the pressure may be provided by mains water pressure. A pump may also be used to pump clean water or another fluid from another source. The wash fluid may be heated to dissolve soap adhering to the sieve structure. If the wash fluid is pressurized by a pump, the power consumption of the pump is a design consideration.Minimizing this power consumption is desirable to reduce the cost of the pump itself and its operating costs.

[0055] FIG. 7a shows an embodiment with a filter pressure regeneration system comprising a nozzle assembly with two rotatable opposing washing nozzles 701a,b extending radially from a central conduit 702. The central conduit 702 delivers pressurized washing fluid to the washing nozzles. The effluent enters the separator via an inlet 703 and passes around a channel formed by the outer wall of the chamber and a sieve structure 704 to a wall 705 where filtered material M accumulates in a trap 706. The washing nozzles 701a,b are aligned perpendicular to the sieve structure 704. The washing nozzles can be rotated by a motor (shown in FIG. 18) or other means. Other means include utilizing the upstream flow of unfiltered effluent to provide energy for the mechanical operation of the propelling nozzles.

[0056] In Fig. 7a, the washing nozzles are rotated in the direction of the effluent flow. Fig. 7b shows a detailed view of waste material M being expelled from the unfiltered side of the sieve structure 704 by jets of washing fluid 707 issuing from washing nozzles 701a. By reducing the number of rotating washing nozzles, it is possible to achieve the same coverage of the jets of washing fluid on the sieve structure as with the array of fixed washing nozzles shown in Fig. 6a, but with lower power required for the washing fluid pump. The washing nozzles can be directed downwards to force the expelled material down towards the trap.

[0057] The washing fluid can be water or a mixture of air and water. Figure 7c shows a jet of washing fluid containing water and air, where water pellets 708 can be seen ejecting from the washing nozzle 701a. This increases the velocity and ejection efficiency of the washing fluid.

[0058] The wash nozzles of the filter pressure regeneration system can be configured such that the components of the pressurized wash fluid are tangential to the filtered side of the sieve structure. Figure 8a shows a filter pressure regeneration system with such an arrangement. The ends of the wash nozzles 801a,b are angled in the direction of the effluent flow. This has the effect of discharging the filtered material further into the effluent flow, where it can be swept further towards the trap 802 under the action of the effluent flow through the sieve structure before redepositing on the sieve structure. Figure 8a shows the nozzle assembly rotating in the direction of the effluent flow. Figure 8b shows the nozzle assembly rotating against the effluent flow.

[0059] FIG. 9a shows an alternative arrangement of a nozzle assembly for a filter pressure regeneration system. A central hub 901 supports an array of wash nozzles 902a, b, etc., extending radially from the hub 901. The hub contains conduits for delivering pressurized washing fluid to the wash nozzles. The wash nozzles are arranged in stacks of four directly on top of each other, with matching stacks arranged directly opposite the hub. This arrangement ensures that the entire width of the sieve structure is washed in each sweep of the nozzle assembly.

[0060] Figure 9b shows a nozzle assembly in which an array of wash nozzles are arranged in a spiral configuration around a central hub, encouraging the discharged filtered material to travel downward in the effluent stream and reach the trap more quickly.

[0061] FIG. 10a shows a nozzle assembly rotation unit 1000 for propelling a nozzle assembly of a filter pressure regeneration system. The nozzle assembly rotation unit 1000 is fixed to a washing nozzle. The rotation unit comprises a central hub 1001 acting as a conduit for the propelling fluid. The propelling fluid and the washing fluid can be the same fluid if the washing fluid conduit and the rotation unit hub are connected. The rotation unit 1000 has radially extending arms 1002a,b which terminate in propelling nozzles 1003a,b oriented perpendicular to the arms. The fluid leaving the propelling nozzles is directed tangentially to the axis of the hub, causing the rotation unit 1000 to rotate and thus the nozzle assembly fixed to it.

[0062] FIG. 10b shows the nozzle assembly rotation unit 1000 in operation.

[0063] 11a shows one embodiment of a separator unit including a filter pressure regeneration system. The separator unit 1100 comprises an outer cylindrical wall 1101. In this embodiment, the outer wall is transparent so that the user can see when the separator is operating and also see the accumulated filtered waste. The separator unit 1100 has a circular cap 1102 and a base 1103. An inlet 1104 is provided in the wall 1101. An outlet 1105 is provided in the base 1103.

[0064] FIG. 11b shows a side view of the separator unit 1100. A cylindrical sieve structure is provided coaxially with the outer wall 1101. The sieve structure extends between the cap 1102 and the base 1103, providing a seal through which unfiltered effluent cannot pass. The sieve structure includes an open support scaffold to which a mesh with an aperture of 50 micrometers is fixed. Mesh sizes in the range of 5 to 150 micrometers are also suitable. The mesh separates the solid material from the liquid components of the effluent. An internal dividing wall 1107 forms a channel for the effluent to start at the inlet 1104 and flow around the sieve structure. The chamber is divided horizontally into two parts by a partition 1108. The partition 1108 has an opening on the other side of the internal dividing wall 1107. The combination of the opening and the lower part of the chamber below the partition 1108 provides a trap 1109 in which waste material can accumulate. The outlet 1105 is connected to a scoop 1110 which collects the filtered effluent that passes through the mesh.

[0065] Figure 11c is a cross-sectional view of separator unit 1000 along line A-A' in Figure 11a, where components of the filter pressure regeneration system are shown. A central vertical conduit 1111 provides washing fluid to a nozzle assembly. The nozzle assembly includes a propelling nozzle 1112 mounted on a rotatable hub 1113.

[0066] Figure 11d is a cross-sectional view of separator unit 1000 along line B-B' in Figure 11a, where components of the filter pressure regeneration system are shown. The nozzle assembly includes wash nozzles 1114a-d mounted on a rotatable hub 1113. The wash nozzles extend radially outward from the hub adjacent the filtered side of the sieve structure.

[0067] A central mounting hub 211 as shown in Figure 2a has a hollow core for delivering wash fluid to the openings that allow it to pass through the rotating nozzles. The mounting hub may be removable from the main filter housing to aid in manufacturability and maintenance of the component.

[0068] The structure to which the mesh is attached may have a user accessible opening hatch, which allows for maintenance of the product during its life, which may be advantageous if the rotating nozzle becomes clogged due to ingress and accumulation of debris over time.

[0069] The separator unit is approximately 15cm in diameter. However, it will be understood that larger or smaller diameters may be selected depending on the application. The size of the unit is selected based on the flow rate of the effluent to be filtered. A separator diameter of 15cm is sufficient to process the effluent from a domestic washing machine flowing at a rate of 13 litres / min.

[0070] The open area of ​​the mesh that allows water to pass through at a given flow rate can be adjusted by changing either the mesh surface area or the mesh aperture. Mesh aperture affects efficiency, so smaller mesh apertures are generally preferred to provide higher efficiency. Mesh surface area is a function of height and diameter, so a given area can be matched by increasing the height if the diameter is reduced, and vice versa. All variables can be adjusted to meet product packaging and efficiency specification requirements.

[0071] In one embodiment, the filtered effluent itself is recirculated to clean the sieve structure. Figure 12 shows a separator unit 1270 having an inlet, a cylindrical housing, and a sieve structure 1203. An outlet 1205 collects the filtered effluent. A portion of the filtered effluent is diverted into a conduit 1206 where it is pressurized by a pump 1207 and directed to a central vertical conduit 1208 that provides washing fluid to a nozzle assembly 1209.

[0072] 13a shows an embodiment suitable for locations below the water line, where a portion of the filtered wastewater is also recirculated to regenerate filter pressure. The separator unit 1300 has an inlet 1301, a housing 1302, a sieve structure 1303, and an outlet 1304. All of the filtered effluent from the outlet 1304 is pumped out via a pump 1305. The pump 1305 is arranged to divert a portion of the filtered effluent back via conduit 1306 to a central vertical conduit 1307 that provides washing fluid to a nozzle assembly 1308. A restriction 1309 is provided in the pump outlet pipe 1310 to ensure that a sufficient amount of fluid is recirculated to the pressure regeneration system. Alternatively, pump 1305 may have a single outlet as shown in Figure 13b and a junction 1312 which diverts some of the filtered effluent to a conduit 1313 for recirculation into the pressure regeneration system and the remainder to a waste line. A restriction 1314 is provided to determine the proportion of filtered effluent that is recirculated. An air inlet 1315 may be provided in conduit 1306 to allow air into the pressure regeneration system to enhance the cleaning effect of a jet of cleaning fluid against the filtered side of the sieve structure.

[0073] It may be advantageous to be able to separately control the drainage and pressure regeneration of the separator unit. A drainage pump and a recirculation pump may be provided.

[0074] An air pump may be used to assist with regeneration and drainage.

[0075] A reservoir having a fluid sensor may be provided beneath the separator unit, the fluid sensor detecting when fluid is present in the reservoir, and a fluid sensor switch arranged to control a pump to drain the unit.

[0076] A pressure sensor can be provided to monitor the change in pressure across the filter chamber to detect when effluent backs up, which can be used to activate a pump to regenerate filter pressure.

[0077] A bypass system may be provided to connect the inlet to the outlet which ensures that if the separator becomes blocked or the regeneration system fails for any reason, the entire wash load of effluent is diverted to the waste outlet without backing up and causing flooding or affecting the performance of the washing machine or drain cycle.

[0078] A pressure operated valve is located within the conduit. The pressure operated valve opens when the pressure at the inlet relative to the outlet exceeds a certain pre-set value. Thus, if effluent backs up to the inlet due to a clogged filter, the valve opens to allow the effluent to pass to the outlet where it can safely drain into a waste pipe. Alternatively, the valve may be of a type that can be electronically controlled. A pressure sensor that detects the pressure difference between the two sides of the sieve structure may control the valve, such that when the pressure difference reaches a predetermined level, the valve is operated and the bypass is activated.

[0079] The dimensions of the unit shown in Figures 6a and 6b can be varied to modify its performance characteristics. For example, the height of the mesh structure 603 can be varied as shown in Figures 14a and 14b, which provides a larger surface area and therefore an increased flow rate. As the height of the mesh is scaled, the height of the nozzle structure is scaled so that in use the entire surface of the mesh is sprayed. Figure 14a shows a mesh 1401a with a height H1, and the unit has a nozzle 1402a that extends over the height H1. Figure 14b shows a mesh 1401b with an increased height H2, and the unit has a nozzle 1402b that extends over the height H2.

[0080] The volume of the chamber can be increased to capture a larger amount of effluent. The volume of the chamber is increased by increasing the diameter or height of the separator. This is shown in Figures 15a and 15b. As the diameter of the mesh structure increases, the diameter of the nozzle assembly is thereby increased. Figure 15a shows a mesh structure 1501a of diameter D1, the unit having a nozzle assembly 1502a with two arms. Figure 15b shows a mesh structure 1501b of increased diameter D2, the unit having a nozzle assembly 1402b, now with three arms, to ensure proper atomization of the mesh structure during use.

[0081] The filter chamber can be provided with features that help to hold the captured microfibers in a particular location for ease of removal. For example, a flap can be provided in the chamber as shown in FIG. 16. Runoff enters at an inlet 1601 and passes around the chamber, guided by the chamber walls 1602 on one side and the mesh structure 1603 on the other. Microplastics accumulate against the end baffles 1604 as the runoff moves around the chamber. When the runoff flow starts and stops with the drain cycle of the washer, the flow of the runoff can reverse and carry the microplastics back around the chamber. A movable flap 1605 is provided that opens when the runoff flow is in one direction (position 1605a) and closes when the flow reverses (position 1605b). The liquid components of the runoff tend to pass through the mesh when the flap is blocked, while the solid microplastics are prevented from moving back into the chamber. The flap 1605 may be a fixed flexible rubber unit or a rigid hinge unit.

[0082] The flaps may also be rigid features that may be perpendicular to the circumference of the chamber, angled to allow effluent to pass in one direction but be restricted from returning. In this embodiment, some effluent may return, but may be advantageous simply to increase manufacturability and robustness of the product.

[0083] The geometry of the chamber can be altered to increase the flow rate of the effluent within the chamber. This can help to increase the filter's ability to separate the effluent and reduce the pressure consumption of the filter system. Figure 17 shows such an arrangement, where a cylindrical chamber 1701 has a center located at C1 and a cylindrical mesh structure 1702 has a center located at C2, where C1 and C2 are offset. This creates a restriction R through which the velocity of the effluent increases.

[0084] The nozzle assembly can be rotated using a direct drive such as an electric motor, as shown in FIG. 18. The chamber 1801 has a mesh structure 1802 and a nozzle assembly 1803, in this case driven by a motor 1804. This has the advantage of improving the reliability of the nozzle assembly. If the rotation of the nozzle assembly is powered by water pressure, the efficiency of the bearing surfaces between the nozzle assembly and the mounting spigot is important. If these surfaces become clogged with debris, the nozzle may stop rotating. Furthermore, using a motor to rotate the nozzle assembly can eliminate the need for a pump to pressurize the washing fluid into the nozzle, where the centrifugal force generated in the nozzle draws the washing fluid into the nozzle and projects it against the sieve structure.

[0085] The nozzle assembly itself can be optimized to reduce blockages from wash fluid containing small amounts of debris. If the wash fluid being used is a recirculated filtered runoff, debris that is too small to be stopped by the sieve structure, or an accumulation of smaller particles that combine to form larger blockages, can get trapped in the nozzle. To overcome this, a wide slot 1901 can be used, as shown in Figure 19a.

[0086] Optimizing the nozzle is important since this is the main determinant of the dispersion and velocity of the washing fluid. Different variations are possible depending on the application. In one embodiment, the nozzle arms can be arranged so that each nozzle set is not identical. The opposing rotating arms can be arranged so that instead of a single nozzle set cleaning the entire surface of the mesh as it rotates, all the remaining mesh surface is cleaned as the second nozzle set follows. This can be advantageous in some scenarios as a more efficient way to direct the washing fluid at a lower velocity, etc.

[0087] In scenarios involving non-identical nozzles, it is taken into account that the volume of fluid emitted from each nozzle is equal to keep the forces balanced between each opposing arm.

[0088] In another embodiment, there may be only a single nozzle arm, as shown in Figure 19b, which may be advantageous to optimize the velocity of the fluid emitted from the nozzle and reduce drag from the nozzle assembly during rotation.

[0089] Other methods to achieve washing of the filter mesh include having a static nozzle assembly as shown in FIG. 20a, or inverting the structure to position the nozzle assembly outside the sieve structure as shown in FIG. 20b. FIG. 20a shows a mesh structure 2001 with an inlet 2002. The mesh structure is rotatable about a central axis. This structure is mounted in a larger chamber (not shown) with an outlet. A stationary nozzle assembly 2003 is provided outside the sieve structure, which rotates to remove debris. A wall may be provided (not shown) on one side of the inlet, so that the effluent is directed through a channel around the sieve structure, so that filtered microplastics removed by the wash water from the washing nozzle accumulate on the side of the wall away from the inlet.

[0090] FIG. 20b shows a rotatable nozzle assembly 2004 located outside a cylindrical mesh structure 2005. Within the mesh structure 2005 is a solid core 2006 that defines a wall. An inlet 2007 is provided on one side of a baffle 2008. Together they direct the effluent around the sieve structure. The entire assembly is mounted within a chamber (not shown) having an outlet for collecting the filtered effluent passing from the inside to the outside of the mesh structure. The nozzle assembly 2004 can be rotated around the mesh structure to direct wash fluid against the mesh to remove material.

[0091] Figure 20c shows an alternative nozzle assembly having a nozzle 2005 arranged to direct a stream of fluid 2010 towards a rotatable object 2011. The object has features 2012 arranged to deflect the stream of fluid outwardly towards a sieve structure 2013. The features 2012 are also arranged to rotate the object such that the emitted fluid sweeps across the surface of the outlet side of the sieve structure, thus clearing debris on the other side.

[0092] The separator system described above may be installed within the washing machine or may be located outside the washing machine and connected to the waste water outlet of the washing machine. A more detailed description of the stand-alone separator is provided below. A separator unit for positioning outside a textile processing device such as a domestic washing machine is shown in Fig. 21a. The unit 2100 comprises a body 2101 with a waste water inlet and outlet (not shown) and a removable jug 2102. The jug contains a filter capable of collecting the filtered microfibers. Removing the jug allows the filtered microfibers to be emptied. Fig. 21b shows the unit 2100 with the jug removed and separated from the unit. The jug has an effluent inlet, an effluent outlet and conduits for pressure-spent regenerating fluid delivery. The pressure-spent regenerating fluid is the recirculated filtered effluent. The conduits terminate in stubs and the body of the unit has openings to receive these conduit stubs, an effluent inlet 2103, a filtered effluent outlet 2104 and a recirculated filtered effluent 2105. Each opening has a watertight seal which ensures that no fluid leaks out of the joint between the stub and the opening when the jug is in place.

[0093] FIG. 22a shows a cross section of the unit 2100 along line A-A' in FIG. 21a. The unit has a waste water inlet 2201 which can be connected to the outlet of a washing machine. A conduit leads to the inlet stub 2202 of the jug 2203 where waste water is directed tangentially into the cylindrical chamber 2204 of the jug 2203 when the unit is in use. Centrally located within the jug 2203 is the cylindrical filter assembly 205 shown in more detail in FIG. 23. It is a plastic cage 2301 with a series of openings between a set of vertical ribs. A mesh (not shown) is overmolded onto the plastic cage. The mesh is flush with the outside of the ribs. A baffle 2302 is provided which forms a wall on one side of the jug inlet 2202 inside the chamber 2204 so that runoff only travels in one direction around the inside of the chamber. The captured particles pass around the filter and collect on the baffle, puddling on the far side of the filter, away from the inlet. This limits the recirculation of the captured particles. The mesh near the inlet is kept clean and free of particles. Thus, when wastewater enters the filter chamber, it can pass through the mesh. The filter assembly has a cap 2203b to prevent unfiltered effluent from overflowing into the outlet. This filter cap can also be removed to allow the user to access the regenerator for maintenance. The cap is designed on the top of the filter assembly to ensure that the captured effluent cannot escape through this path during maintenance. The jug 2203 has an open top to allow the user to access the inside to remove the filtered microplastics. The jug 2203 has an exterior rim with a flange 2206. When the jug 2203 is installed in the unit, a lid 2207 is lowered onto the jug. The lid includes a seal 2208 that engages with the flange 2206. Lever 2209 operates a mechanism which lowers the lid onto the jug and provides a watertight seal of the jug within the unit.

[0094] In another embodiment, the filter lid can be a removable component that is assembled by the user by rotating the lid around the filter body and held in place with tabs.

[0095] Located within the filter assembly of the jug is a pressure consuming regenerator comprising a rotatable nozzle assembly 2210 mounted on a hollow spigot 2211. The rotatable nozzle assembly is captured on the spigot by a filter assembly cap 2203b. The spigot is fed by a conduit routed through the unit to a recirculation pump 2216a, shown in FIG. 22b, which can provide washing fluid to the nozzle assembly. The nozzle assembly is shown in more detail in FIG. 24. Two hollow arms 2402a, 2402b are connected to a central hub 2401, which are offset from the axis of rotation and project tangentially from the hub. The end of each arm has a vertical row of flexible nozzles 2403a, 2403b arranged to extend across the height of the mesh. The nozzles can be flexible so that they can easily break up accumulated limescale. The nozzles can be rigid. The offset tangential arrangement of the nozzle assembly means that when pressurized fluid is forced through the nozzle by the recirculation pump, the assembly is rotated at about 30 to 150 rpm. The rotation is arranged to be in the opposite direction to the flow of fluid around the chamber. In this way, the impingement angle of the jet of fluid emitted from the nozzle is integrated with the effluent flow, which allows the dislodged debris to flow further around the mesh than if the angle was against the effluent flow. Figure 25 shows the nozzle assembly in place in the jug assembly. The spigot with the regenerator attached acts as a plain bearing. The spigot has bleed paths in the upper and lower sections that allow a certain amount of washing fluid to exit. This is limited by a labyrinth seal in the groove. It is important to allow the washing fluid to exit from here, to ensure that any debris that may pass into this mechanical system can also be passed out and limit the risk of blockage. The groove has a tolerance such that it allows the largest particle that can pass through the mesh aperture in any orientation to pass through this bearing.

[0096] The jug 203 is provided with a molding 2212 which collects the filtered effluent that has passed through the mesh. This molding directs the effluent to a jug outlet 2213. The jug outlet feeds two reservoirs, a recirculation reservoir 2214 and a drain reservoir 2215. The recirculation reservoir is connected to a recirculation pump 2216a. The drain reservoir is connected to a drain pump 2216b shown in FIG. 22b. The outlet from the drain pump feeds a chamber 2217 which has a one-way valve 2218 to prevent the filtered effluent from returning to the reservoirs 2214, 2215. The filtered effluent leaves the unit via an outlet 2219.

[0097] When draining the filter unit, the reservoirs are arranged to prioritize filling of the recirculation reservoir before the drain reservoir, ensuring that there is always a supply of washing fluid for recirculation and that it is not removed by the drain pump.

[0098] The volume of the recirculation reservoir is designed to ensure a supply of washing fluid that can provide constant recirculation without completely emptying the reservoir. In some scenarios, it may be advantageous to limit this and provide only enough washing fluid for a "burst", since reducing this volume makes it possible to reduce product size.

[0099] In another embodiment, the reservoir and other components may be located at a distance from the filter unit and connected by conduits. Separating these components may be advantageous as it provides flexibility when integrating the filter into another system, for example inside a washing machine.

[0100] The volume of the drain reservoir is designed to ensure that any backflow fluid from the outlet duct and hose pipe can fill back into this chamber without overflowing. This ensures that the user can remove the filter jug ​​when the product is installed near floor level and no overflow will occur.

[0101] The reservoir geometry is designed with an angled base and a central feed point for the pump, which reduces settling in the tank by eliminating static flow areas in the tank and creating a dynamic drainage environment that encourages particles to move to the feed point and be removed by the pump along with any wastewater.

[0102] The reservoir geometry and depth are further designed to limit swirl in the pump, which would otherwise reduce the ability to draw water into the pump and reduce the pump's operating efficiency.

[0103] The inlet 2201 and outlet 2219 of the unit 2100 are connected by a conduit 2220. A distribution valve 2221 is provided at the entrance to the conduit 2220. The distribution valve opens at a predetermined pressure so that if there is a fault in the unit and pressure rises, the valve operates and the effluent bypasses the filter section of the unit and flows directly to the outlet. A one-way valve 2222 is provided to prevent recirculation of the filtered effluent and a one-way valve 2223 is provided to prevent the effluent from bypassing to enter the reservoir. In another embodiment of the design, the user can access the bypass for maintenance, for example to remove a blockage.

[0104] There is a valve that seals around the spigot of the filter jug ​​when assembled into the stationary conduit. There is also a passive one-way valve at the inlet to the filter unit that opens on insertion of the inlet spigot and closes automatically if there is effluent flow when the filter unit is removed.

[0105] An air valve 2224 is provided at the inlet to prevent the recirculation pump and / or drain pump from drawing water from the connected washing machine to ensure that sufficient water remains in the washing machine.

[0106] FIG. 26 shows the arrangement of the electronic control system of the unit mounted on a PCB 2601. Two sensors are provided, namely i) a capacitive sensor at the inlet of the duct or other area depending on the control method and software logic to detect the presence of effluent, and ii) a pressure differential sensor arranged to measure the pressure difference between the two sides of the mesh. The pressure differential sensor can be used to indicate the pressure difference between each side of the mesh. This can be used to monitor the health of the system and to provide feedback to the logic such as indicating if the mesh is about to become clogged with debris and a regeneration should be activated. A microswitch 2602 is provided to detect when the jug is fully located in the unit. Any other type of sensor such as an IR sensor could be used to detect mechanical movement. If the jug is not located and the unit is switched on, an alarm sounds to warn the user to position the jug before use. This can also be operated on a timer to remind the user during maintenance to replace the jug and not leave the unit disassembled.

[0107] A capacitive sensor is one type of fluid sensor, any other type such as a float switch can be used.

[0108] The electronic system is arranged to operate the unit in multiple modes with different combinations of sensors and software logic to optimize or modify system operation for different geographic, user, functional or cost requirements. For example, only capacitive sensors can be used (without pressure sensors) to reduce component count and cost. The following are examples of modes of use:

[0109] Example 1 - Capacitive and Pressure Sensors Active Filtering: If the volume sensor indicates that there is effluent at the inlet (i.e. the washer is emptying) and the pressure sensor indicates that the mesh is clogged, the drain pump can be activated to drain the unit and the recirculation pump is activated to spray the mesh to remove debris and regenerate pressure drain. Active filtering, once triggered, can run for a set period of time.

[0110] Passive Filtering: If the pressure sensor indicates that the pressure difference is below the threshold and the volume sensor is triggered, passive filtering begins, which is when the recirculation pump is turned off and only the drain pump is operated if desired.

[0111] Drain cycle: If the capacitance sensor indicates that the effluent at the input has stopped or the pressure sensor indicates that no fluid has passed through the filter for a period of time, the recirculation pump is operated after a delay that may be about 100 seconds to wash the mesh. This delay is adjustable. Immediately after, for example, 2 seconds, the drain pump is activated to drain the system. The recirculation pump is then turned off after, for example, another 3 seconds, and then the drain pump is turned off after, for example, 10 seconds. If the capacitance sensor detects input effluent, the drain cycle is interrupted and the filtration mode is started again.

[0112] stand-by: If the capacitance sensor does not detect any water and a drain cycle is performed, both the recirculation pump and the drain pump are turned off.

[0113] Example 2 - Capacitive Sensor Only A capacitance sensor is provided on the inlet tube. When water is detected, the pump is activated until water is no longer detected. The pump is programmed to overrun for a predetermined number of seconds to wash the mesh and drain the filter.

[0114] Example 3 - Capacitive sensor with current monitoring on a drain pump. A capacitance sensor is provided on the inlet tube. If water is detected, the drain pump is turned on. If the current on the drain pump is low while the fluid sensor reads high, the recirculation pump is turned on. The recirculation pump is turned off after a predetermined time while the drain pump remains on.

[0115] Example 4 - Washing machine integrated - pressure sensor only The separator unit may be integrated into a washing machine or other textile processing equipment. Integration with the washing machine control logic allows the filter to know when water is being pumped through the filter so no fluid sensor is required. When fluid is being pumped through the filter and the pressure sensor is low, the recirculation pump is not run, but the drain pump (if installed) may be activated. When fluid is being pumped through the filter and the pressure sensor is triggered, the recirculation pump is run. The washing machine drain cycle may be paused for a few seconds at this point to increase the effectiveness of the pressure drain regeneration.

[0116] The unit can be used to reduce the water consumption of existing washing machines or other textile processing equipment by recirculating the water from the output back to the washing machine. This is possible because the filter removes a high percentage of debris from the effluent, which is therefore very clean. A unit integrated into the washing machine can also provide this function.

[0117] The separator unit can be integrated into washing machines and used to replace traditional filters used to prevent debris from reaching and damaging the washer pump. Additionally, by replacing the existing filters with the advanced filtration technology disclosed herein, different washer pumps can be used together, operating at higher efficiency.

[0118] A separator may be provided with an inlet feeding the inside of the sieve structure and an outlet collecting filtered effluent from the outside of the sieve structure.

[0119] The separator housing can be opened to empty the trap when the effluent has been drained.

[0120] To avoid airlocks, an opening may be provided at the top of the sieve structure.

[0121] To avoid all the waste water being siphoned from the washing machine, an air inlet may be provided at the inlet of the separator.

[0122] As an alternative to regenerating the pressure of the separator unit, a disposable cartridge may be provided. The portion of the separator containing the filtration element, i.e., the sieve structure, may be provided as a cartridge, which is removed, discarded, and replaced with a new one. Alternatively, the cartridge may be sent for cleaning and then reused.

[0123] Wastewater discharged from textile factories is contaminated with microfibers and is not guaranteed to be filtered by municipal facilities. These facilities, where present, can remove up to 98% of microplastics, but what escapes still amounts to millions of microfibers every day. The microfibers removed from the water can then be sent to the environment as "sewage sludge" or spread on agricultural land as fertilizer. Ultimately, the microfibers are sent to the natural environment as pollutants, and they need to be stopped at the source.

[0124] Wet processing plants currently operate in a linear system whereby microfiber resources are discharged from the technological process as a pollutant into the biological environment. The use of the separator system described herein closes the loop into a continuous cycle to preserve the value of the microfiber within the technological process and stop the damage to the biological environment.

[0125] One embodiment of the separator system can be retrofitted to existing wastewater outlets of wet-processing textile mills to allow for the capture of microfibers at the source before potential contamination of the natural environment occurs.

[0126] The separator system can be used to filter microplastics and other small pollutants from environmental drainage systems, such as roadside gutters. Many microplastics in the environment are broken down from larger items of plastic, such as automobile tires, road surfaces and road markings. After synthetic fibers, tires are the largest source of microplastics and contain harmful materials such as mineral oil.

[0127] Catalytic converters are fitted to most automobiles and contain highly valuable materials such as platinum, palladium, copper and zinc. During use, small amounts of these metals are lost from the car and debris is deposited on the road surface. Although metal concentrations vary geographically, the collection and recycling of these materials not only reduces environmental pollution but can also be a source of income in a circular economy.

[0128] Larger scale embodiments of the invention may be applied to the treatment of effluent in wastewater treatment plants, for example the separator chamber may be one or two meters in diameter or larger.

[0129] A typical sewer network is built according to one of two designs: i) Combined sewers: These mean that surface water and sewage are collected together and all the wastewater passes through a Wastewater Treatment Plant (WWTP). During heavy rainfall, it is common for the sewers to overflow, releasing raw sewage and pollutants into water bodies. ii) Separate sewer pipes, which discharge surface water directly into water bodies.

[0130] In both systems, roadside runoff, i.e. surface water from the road, is discharged into the environment.

[0131] Most roadside gutters have drains located at regular points that have sediment "pots" that allow heavier materials like gravel and sand to settle and prevent blockages. These retain some micro-pollutants, but most of the microplastics and valuable metals are too small to be retained.

[0132] One embodiment of the separation system of the present invention can be retrofitted as an insert into the drain's sediment pot to filter micro-contaminants at the source. It is designed to fit into existing gutters and be emptied using a mobile vacuum pump.

[0133] In another embodiment, the system can be used as part of a filtration system for marine waste treatment. At sea, transport ships dump contaminated wastewater from on-board activities, including microplastics from various sources. The filter system can be applied to filter this effluent before disposal, thus combating this source of pollution.

Claims

1. 1. A separator suitable for separating solid materials from a fluid, comprising: A chamber (601) having an inlet (602) and an outlet (605); a sieve structure (603) forming a permeability barrier between the inlet and the outlet for filtering the fluid, the sieve structure (603) thus having an inlet side for unfiltered fluid and an outlet side for filtered fluid, the sieve structure (603) being coaxial within the chamber; the separator further comprising a filter pressure recovery device for removing filtered material from the sieve structure; the filter pressure recovery device comprising a conduit (1208) and a nozzle assembly (1209) having at least one wash nozzle (701) for directing a wash fluid towards the outlet side of the sieve structure to remove filtered material from the inlet side of the sieve structure; the chamber includes a channel formed from a wall of the chamber and the sieve structure, the inlet being located at one end of the channel, such that, in use, the fluid flows through the channel and the material removed by washing fluid from the washing nozzle is swept by the movement of the fluid away from the inlet towards the other end of the channel; the inlet is arranged to direct fluid into the chamber tangentially onto the sieve structure, and a wall (604) is provided on one side of the inlet such that the fluid is guided circumferentially through the channel and around the sieve structure, such that filtered material removed by the washing fluid from the washing nozzle is swept around the chamber by the fluid flow and accumulates on a side of the wall remote from the inlet.

2. 10. The separator of claim 1, wherein a trap with an opening to a subchamber is provided at the base of the channel to allow collection of the accumulating filtered material.

3. The separator of claim 1 , wherein the nozzle assembly comprises a plurality of wash nozzles rotatable about a central axis of the sieve structure.

4. 2. The separator of claim 1, wherein the wash nozzles are disposed opposite one another and mounted to a central feed tube.

5. The separator of claim 3 , wherein the nozzle assembly is rotated by a motor.

6. 4. The separator of claim 3, wherein the nozzle assembly is rotated by a propelling nozzle disposed to direct a fluid flow having a vector that is tangential to a circumference of the sieve structure.

7. The separator of claim 1 , wherein the cleaning nozzles are disposed to direct cleaning fluid perpendicular to the sieve structure.

8. The separator of claim 1 further comprising a pump in fluid communication with the outlet of the chamber.

9. The separator of claim 1 , wherein the pump is arranged to drain the separator.

10. 10. The separator of claim 9, wherein the pump is disposed to recirculate the filtered fluid to the conduit of the filter pressure regeneration device.

11. 2. The separator of claim 1, wherein a sensor is provided, and the filter pressure regeneration device is arranged to be activated according to an output from the sensor.

12. 10. The separator of claim 1, wherein a bypass conduit is provided between the inlet and the outlet to provide an alternative path for fluid if fluid flow is interrupted.

13. A washing machine comprising the separator according to any one of claims 1 to 12.

14. A method for operating a separator according to any one of claims 1 to 12, comprising the steps of: filtering a fluid through the sieve structure; washing the filtered side of the sieve structure with a jet of washing fluid from a nozzle to clean accumulated debris from the unfiltered side of the sieve structure and regenerate pressure consumption of the separator.

15. 15. The method of claim 14 including the further step of sweeping the nozzle across the outlet side of the sieve structure.

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