Separator with pump

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 filters to remove microplastics in effluent from any source, but particularly to removing microfibers from domestic and commercial washing machine wastewater, industrial textile processing waste, and roadside runoff. A separator for separating microplastics from 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 effluent, and a pump in fluid communication with the outlet of the chamber.

Description

[Technical field]

[0001] The present invention relates to preventing microplastics from entering the environment. In particular, the present invention is directed to regenerating the pressure consumption of filters to remove microplastics in effluent from any source, but particularly to removing microfibers from domestic and commercial washing machine wastewater, industrial textile processing waste, and roadside runoff.

[0002] 2. Description of Related Art 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. An electronic valve under the control of a CPU 104 manages the water entering the drum 101. 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 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] FIG. 2a shows a typical domestic washing machine setup with the washing machine 201 sitting on the floor 202 below the work surface 203. The waste output 204 of the washing machine is fed into an open waste pipe 205. The opening of the waste pipe is above the floor by a given height, typically 30-100cm, and is open to prevent all the water from being siphoned out of the washing machine when draining. The top 206 of the waste pipe is known as the water line, and the washing machine's pump needs to be powerful enough to raise the waste above this water line in order to effectively drain it. When the washing machine is first filled, a certain amount of water is needed to fill the area below the drum before the drum itself is filled, and the drum is where the water is actually needed for the washing process to take place. Typically, washing machines are designed to keep a small reservoir of water between washes, so that no extra water is needed to be made available in the drum. This is advantageous because the first water to reach the drum contains detergent as it is washed from the drawer into the drum. Without the small reservoir of water, detergent would be lost and the washing process would be ineffective.

[0012] 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.

[0013] 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.

[0014] Microfiber separators have been developed that can be retrofitted externally to a washing machine by connecting the output of the washing machine to a stand-alone separator unit and routing the output of the separator unit to an open wastewater pipe. However, the location of such separator units is limited to above the water line. If such separator units are located below the water line, they will not drain completely and will fill up with contaminated wastewater, creating problems in emptying the unit. Therefore, such separator units need to be located above the water line. However, as shown in Figure 2b, mounting the separator unit above the water line can be problematic. The filter unit 207, shown in dotted lines, needs to be located above the water line, but the clearance between the work surface 203 and the top of the wastewater pipe 206 is insufficient to allow this.

[0015] SUMMARY OF THE PRESENT EMBODIMENT It is therefore an object of the present invention to provide a separator unit that can be mounted anywhere, including below the water line.

[0016] Another problem is that mesh filters can quickly become clogged and when this happens, their effectiveness is significantly reduced, which can cause pressure drops and reduced flow rates, leading to damage to pumps and other components of the system as well as flooding.

[0017] It is therefore a further object of the present invention to provide a separator unit for separating microfibers from an effluent that does not clog and maintains an effective operating pressure over time. Summary of the Invention

[0018] 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 effluent; and a pump in fluid communication with the chamber; The separator further comprises a filter pressure recovery device for removing the filtered material from the sieve structure, the filter pressure recovery device comprising a conduit and a nozzle assembly having at least one cleaning jet directed toward the outlet side of the sieve structure, the pump being arranged to recirculate the filtered fluid to the conduit of the filter pressure recovery device, the sieve structure having a circular cross section and a channel formed between the chamber and the sieve structure such that, in use, the fluid is directed circumferentially around the sieve structure through the channel. Although the description herein is directed to filtering microplastics from effluent, the separator may be applied to separate any solid material from any fluid.

[0019] The at least one cleaning jet may be for directing a fluid towards the outlet side of the sieve structure.

[0020] The pump may be a water pump that is also arranged to drain the separator, or a separate pump may be provided for draining the separator.

[0021] A restriction may be provided in the conduit downstream of the pump, and the aperture of the restriction may be set to ensure that a preset amount of filtered fluid is recirculated to the filter pressure regeneration device and a certain amount of filtered fluid is drained.

[0022] The conduit between the pump and the filter pressure regeneration device may be provided with a vent for introducing air into the conduit.

[0023] The filter pressure regeneration device may include a conduit and a nozzle assembly having at least one cleaning jet directed toward the outlet side of the sieve structure, and a second pump is arranged to recirculate the filtered fluid through the conduit of the filter pressure regeneration device.

[0024] 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.

[0025] The water pump may be a positive displacement pump or a centrifugal pump.

[0026] The filter pressure regeneration device may include a conduit and a nozzle assembly having at least one cleaning nozzle oriented toward the outlet side of the sieve structure.

[0027] The chamber may be cylindrical, the sieve structure may be a coaxial cylinder within the chamber, and a wall may be provided on one side of the inlet so that fluid is directed through the channel and around the sieve structure so that filtered solids dislodged by washing fluid from at least one washing jet accumulate on the side of the wall away from the inlet. Advantages of this arrangement, where the filtered solid material travels along the channel, are better utilization of space, increased solid material collection capacity, and ease of handling of the filtered solids.

[0028] A trap with an opening into the subchamber at the base of the channel can be provided to collect the accumulating filtered solids.

[0029] The nozzle assembly may include a plurality of cleaning nozzles that are rotatable about a central axis of the sieve structure.

[0030] The nozzle assembly may be rotated by a propulsion nozzle disposed to direct the flow of water. 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.

[0031] The nozzle assembly is offset from the central axis of rotation and thus may be rotated by the arrangement of the wash nozzle providing the motive force.

[0032] The chamber may have a closed top and bottom.

[0033] The structure may have an opening at the top to release pressure.

[0034] The separator may further comprise a filter pressure regeneration device for removing filtered material from the sieve structure, and a sensor such as a fluid detector is provided, the filter pressure regeneration device being arranged to be activated in accordance with an output from the fluid detector.

[0035] A reservoir may be provided beneath the chamber, with the sensor located proximate to the reservoir.

[0036] The sensor may be a fluid detector such as a float switch, a capacitive sensor, an ultrasonic detector, an optical sensor, or a pressure sensor.

[0037] A bypass conduit may be provided between the inlet and outlet to provide an alternative path for the fluid if the fluid flow is interrupted.

[0038] The nozzle assembly may include nozzles arranged to direct a flow of fluid toward a rotatable plate, the plate being arranged to rotate under the force of the fluid flow and to project the fluid outwardly toward the sieve structure.

[0039] In one embodiment, a washing machine is provided having a separator as described above.

[0040] In one embodiment, a method of operating a separator of the type described above is provided, the method including filtering a fluid through a sieve structure and operating a pump to pressurize the filtered fluid.

[0041] The pump may be operated to drain the separator.

[0042] The pump may be operated to recirculate the filtered fluid to a pressure regeneration device arranged to spray the washing fluid onto the filtered side of the sieve structure to remove debris from the unfiltered side of the sieve structure. [Brief description of the drawings]

[0043] [Figure 1] 1 shows a typical domestic washing machine. [Figure 2a] Shows under-counter washing machine. [Figure 2b] This shows the location of the separator on the outside of the washing machine. [Figure 3a] 1 shows a conventional separator. [Figure 4] 1 shows a cross section of a conventional filter assembly. [Diagram 5] 1 shows a cross-sectional view of an embodiment having a discharge pump. [Figure 6] 1 is a graph illustrating the effectiveness of different types of filter assemblies. [Figure 7] FIG. 1 shows a cross-sectional view of an embodiment having a single nozzle for regenerating the pressure drain of a filter. [Figure 8] FIG. 1 shows a cross-sectional view of an embodiment having a single nozzle for regenerating pressure drain of a filter with a combined recirculation and drain pump. [Figure 9] FIG. 1 shows a cross-sectional view of an embodiment having a single nozzle for regenerating the pressure drain of a filter with separate recirculation and drain pumps. [Figure 10]FIG. 1 shows a cross-sectional view of an embodiment having a single nozzle for regenerating the pressure drain of a filter with a recirculation pump and an air exhaust pump. [Figure 11] 1 shows a cross-sectional view of an embodiment having an array of nozzles for regenerating pressure drain of a filter. [Figure 12a] 1 shows an embodiment having a cylindrical sieve structure and an array of stationary wash nozzles. [Figure 12b] 12a shows another view of the embodiment of FIG. [Figure 13a] 1 illustrates an embodiment having a rotating cleaning nozzle. [Figure 13b] 1 shows a detailed view of waste material being expelled from the unfiltered side of the sieve structure by spraying a jet of fluid from the filtered side of the sieve structure. [Figure 13c] FIG. 2 shows a detailed view of water pellets being ejected from a nozzle. [Figure 14a] 13 shows an alternative arrangement of the cleaning nozzle. [Figure 14b] 13 shows an alternative arrangement of the cleaning nozzle. [Figure 15a] 1 shows a propulsion nozzle assembly. [Figure 15b] 1 shows the propulsion nozzle assembly in operation. [Figure 16a] FIG. 2 shows a perspective view of one embodiment of a separator. [Figure 16b] FIG. 2 shows a cross-sectional view of one embodiment of a separator. [Figure 16c] FIG. 2 shows a cross-sectional view of one embodiment of a separator. [Figure 16d] FIG. 2 shows a cross-sectional view of one embodiment of a separator. [Figure 17] 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 18a] 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 18b] 1 shows an alternative arrangement of pumps and conduits; [Figure 19a] FIG. 1 shows a cross-sectional view of one embodiment of a separator having separate recirculation and drain pumps for recirculating filtered effluent as a wash fluid and for draining the separator. [Figure 19b] 1 illustrates an alternative embodiment of a separate regeneration and drainage pump design. [Figure 19c] An alternative embodiment is shown that uses a single pump that can alternate between supplying wash water and draining the filter through the use of a valve. [Figure 19d] An alternative embodiment of a single pump is shown, pumping water to both regeneration and drainage simultaneously. [Figure 20a] FIG. 1 shows a cross-sectional view of one embodiment of a separator having a water pump for recirculation and an air pump for draining the separator. [Figure 20b] 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. [Figure 27a] 1 shows a washing machine with one embodiment of the separator installed therein. [Figure 27b] 1 shows a washing machine with an embodiment of a separator retrofitted to its exterior. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0044] 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 they are equally 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 / or any other domestic or commercial textile processing equipment. 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.

[0045] The separators described herein can be installed within the appliance itself during manufacture, as shown in FIG. 27a, or can be retrofitted to the outside of the washing machine or other appliance, as shown in FIG. 27b.

[0046] The separator system 2800 described above can be installed in a washing machine, as shown in FIG. 27a. Waste from the washing machine drum connects to the inlet 2807 of the separator 2800, and the outlet of the separator connects to the waste outlet 2809. A supply of unused 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. 27b. The inlet 2809 feeds the effluent into the separator 2808, and the 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 unused water is not required. The device can be connected to a power source (not shown) to operate the pump.

[0047] It will be further appreciated 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 contaminated. This also includes runoff from roadside drains.

[0048] 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 to the harsh and diverse compounds it comes into contact with, and is well suited to filtering any solid materials that become entrained in the effluent.

[0049] 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.

[0050] In a typical wash, the highest concentration of microfibers ranges from 5mm to 150um, 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 50um 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.

[0051] A conventional separator or filter arrangement is shown in FIG. 3. An inlet 301 directs effluent into a filter housing 302 in which a sieve structure 303 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 dimensions. The filtered effluent passes through the sieve structure 303 to an outlet 304. 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. 3 becomes clogged quickly by filtered debris, which results in its pressure consumption increasing and its efficiency decreasing.

[0052] 4 shows an alternative arrangement in which effluent inlet 401 is located at one end of a channel 402, with a sieve structure 403 forming the wall of the channel 402. In this way, the incoming effluent pushes filtered waste towards the other end of the channel.

[0053] FIG. 5 is an embodiment of the present invention, a separator unit 208 that can be mounted below the water line as shown in FIG. 2b. The separator unit comprises an inlet 501, a housing 502, a sieve structure 503, and an outlet 504. The outlet is fitted with a pump 505 that can drain the filter unit. Without the pump, runoff would accumulate in the pipe between the top of the washer outlet and the water line if the separator unit was mounted below the water line. With the pump 505 fitted, all runoff that accumulates in the washer outlet pipeline 209 on the unfiltered side of the separator can be pulled through the separator and all filtered runoff on the outlet side can be pushed up the separator outlet pipeline 210 on the filtered side of the separator into the wastewater pipe 205. The pump can be a positive displacement pump or a centrifugal pump or any other type of pump.

[0054] Providing a pump allows for greater freedom in filter location, which is advantageous for users who may be limited in where they can position the filter.

[0055] During use, as effluent fills the chamber, particles are filtered out and remain attached to the outside of the mesh, increasing power consumption and reducing the efficiency of the filter as the mesh begins to clog.

[0056] Curve 1 in Figure 6 is a measure of the effectiveness of the arrangement shown in Figure 5, assuming constant contamination levels and constant wastewater flow rate. The y-axis represents the fluid pressure at the inlet 201, i.e. P, which can be seen to rise gradually and then exponentially as the mesh becomes clogged with filtrate.

[0057] 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 FIG. 6 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.

[0058] 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 regenerating the pressure consumption of mesh filters used to separate microplastics from effluent streams.

[0059] FIG. 7 shows an embodiment of the present invention for separating microplastics from effluent, regenerating the pressure consumption of the filter, comprising an effluent inlet 701 feeding a channel bounded by a filter housing 702 and a sieve structure 703. The filtered effluent leaves the separator via an outlet 704. A washing nozzle 707 is provided arranged to direct a washing jet of washing fluid to the filtered side of the sieve structure 703. The washing nozzle 707 is connected to a source of washing fluid by a conduit 708. 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, thus allowing more effluent to be filtered, thus regenerating the pressure consumption. Once the waste material is removed, the flow of effluent carries the waste material further away from the inlet towards the far end of the channel. In this embodiment, the supply of washing fluid is the filtered effluent itself. A conduit 705 delivers the filtered effluent to a pump 706 which delivers pressurized washing fluid to a washing nozzle 707. This unit could not be mounted below the water line.

[0060] FIG. 8 is a further embodiment in which filter pressure is regenerated and the separator unit can be mounted below the water line. A pump 805 is provided to drain the unit and supply pressurized washing fluid to the washing nozzle 807. The separator unit comprises an inlet 801 to a housing 802 supporting a mesh filter 803. An outlet 804 of the unit is connected to the pump 805. The pump is arranged to direct filtered effluent into a conduit 806 which provides pressurized washing fluid to the washing nozzle and also empties the separator via an outlet 808. The amount of filtered effluent emptied from the washing machine when the filter is operating is much greater than the amount of filtered effluent required for the washing nozzle. Therefore, a restriction 809 in the outlet 808 is required to provide sufficient resistance to flow through the outlet to encourage the filtered effluent to enter the washing fluid conduit 806.

[0061] Optionally, an air inlet 810 may be provided in the wash fluid conduit 806 for introducing air into the wash fluid. This may increase the effectiveness of the wash fluid in removing debris from the sieve structure.

[0062] It may be advantageous to be able to separately control the drainage and pressure regeneration of the separator unit. Figure 9 shows one embodiment which allows this by providing two pumps, a drainage pump 905 and a recirculation pump 908. The separator unit has an inlet 901 to a housing 902 which supports a sieve structure 903 which separates the inlet 901 from the outlet 904. The outlet 904 has a conduit which leads to the drainage pump 905. Also on the filtered side of the sieve structure is a wash fluid conduit 907 which leads to a wash fluid pump 908 and a further wash fluid conduit 909 which feeds a wash nozzle 910. The drainage pump 905 may be a positive displacement or centrifugal pump operating at approximately 0.1 bar and 15 liters / min, but may range up to 1 bar and 30 liters / min. The recirculation pump 1408 operates at approximately 0.3 bar and 8 liters / min, but may range up to 5 bar and 15 liters / min.

[0063] Figure 10 shows an alternative embodiment of the separator unit, using an air pump to assist regeneration and drainage. An inlet 1001 is provided in a housing 1002 supporting a sieve structure 1003 separating the inlet 1001 from the outlet 1004. A conduit leads to a pump 1006 which pumps the filtered effluent to a further conduit 1007 which delivers the washing fluid to a washing nozzle 1008. An air pump is connected to the further conduit 1007 and pumps air into the washing fluid system. The air enhances the cleaning effect of the washing fluid jet emitted from the washing nozzle 1008. The air pump can also be operated to push out any residual fluid in the filter, which allows this embodiment to be mounted below the water line. It may be necessary to provide a one-way valve at the inlet (not shown) to prevent the fluid being pushed back into the washing machine.

[0064] 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 11 shows an embodiment for separating microplastics from effluent, comprising a filter housing 1102 and an effluent inlet 1101 feeding a channel bounded by a sieve structure 1103. The filtered effluent leaves the separator via an outlet 1104. The nozzle assembly 1105 comprises a number of washing jets 1105a, b, c, d, e to which washing fluid is fed by a conduit 1107. 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 flow of the effluent carries it further away from the inlet towards the far end of the channel.

[0065] 12a and 12b 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 1201 is provided with an inlet 1202 and a central cylindrical sieving structure 1203. A wall 1204 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 1201, the external wall of the sieving structure 1203, and the wall 1204 define a channel through which the unfiltered effluent can flow to the other side of the wall 1204 and accumulate there. An aperture 1205 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 1206 that projects radially outward from the conduit 1206 and delivers washing fluid to an array of washing nozzles 1207 arranged to direct washing fluid vertically at the filtered side of the sieve structure 1203 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 1205, and into a trap. 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 remove 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, with pressure provided by mains water pressure. A pump may also be used to pump clean water or another fluid from another source, or to recirculate filtered water. 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 as well as its operating costs and energy consumption.

[0066] FIG. 13a shows an embodiment with a filter pressure regeneration system comprising a nozzle assembly with two rotatable opposing washing nozzles 1301a,b extending radially from a central conduit 1302. The central conduit 1302 delivers pressurized washing fluid to the washing nozzles. The effluent enters the separator via an inlet 1303 and passes around a channel formed by the outer wall of the chamber and a sieve structure 1304 to a wall 1305 where filtered material M accumulates in a trap 1306. The washing nozzles 1301a,b are aligned perpendicular to the sieve structure 1304. The washing nozzles can be rotated by a motor (not shown) or other means. In FIG. 13a, the washing nozzles are rotated with or against the direction of the effluent flow. FIG. 13b shows a detailed view of waste material M being expelled from the unfiltered side of the sieve structure 1304 by a jet of washing fluid 1307 emitted from the washing nozzle 1301a. By reducing the number of rotating wash nozzles or reducing the aperture area, one can achieve the same coverage of the wash fluid jets on the sieve structure as with the array of stationary wash nozzles shown in Figure 12a, but with lower power required for the wash fluid pump. The wash nozzles can be directed downward to force the discharged material down towards the trap. This arrangement is beneficial because it allows the diameter of the sieve structure, and therefore the surface area of ​​the mesh, to be increased without the need for additional wash nozzles.

[0067] The washing fluid can be water or a mixture of air and water. Figure 13c shows a jet of washing fluid containing water and air, where it can be seen that water pellets 1308 are ejected from the washing nozzle 1301a. This increases the velocity and ejection effect of the washing fluid.

[0068] In another embodiment, the nozzle assembly may be attached to a motor having a shaft on which an impeller is mounted, the impeller being mounted within the reservoir. The motor simultaneously spins the spinner and impeller. The impeller drains water from the reservoir. The outlet has a recirculation channel and a drain channel, and the water flow is pumped through both, draining the separator and spraying the filtered effluent onto the filtered side of the sieve structure.

[0069] The wash nozzle of the filter pressure regeneration system can be constructed so that the components of the pressurized wash fluid are tangential to the filtered side of the sieve structure. The end of the wash nozzle can be 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 under the action of the effluent flow through the sieve structure before redepositing on the sieve structure. The nozzle assembly can be rotated in the direction of the effluent flow or against the effluent flow.

[0070] FIG. 14a shows an alternative arrangement of a nozzle assembly for a filter pressure regeneration system. A central hub 1401 supports an array of washing nozzles 1402a, b, etc., extending radially from the hub 1401. The hub contains conduits for delivering pressurized washing fluid to the washing nozzles. The washing 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.

[0071] Figure 14b 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.

[0072] FIG. 15a shows a nozzle assembly rotation unit 1500 for propelling a nozzle assembly of a filter pressure regeneration system. The nozzle assembly rotation unit 1500 is fixed to a washing nozzle. The rotation unit comprises a central hub 1501 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 1500 has radially extending arms 1502a,b which terminate in propelling nozzles 1503a,b oriented perpendicular to the arms. The fluid exiting the propelling nozzles is directed tangentially to the axis of the hub, causing the rotation unit 1500 to rotate and thus the nozzle assembly fixed to it.

[0073] FIG. 15b shows the nozzle assembly rotation unit 1500 in action.

[0074] 16a shows one embodiment of a separator unit including a filter pressure regeneration system. The separator unit 1600 comprises an outer cylindrical wall 1601. 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 1600 has a circular cap 1602 and a base 1603. An inlet 1604 is provided in the wall 1601. An outlet 1605 is provided in the base 1603.

[0075] FIG. 16b shows a cross section of the separator unit 1600. A cylindrical sieve structure is provided coaxially with the outer wall 1601. The sieve structure extends between the cap 1602 and the base 1603, providing a seal through which unfiltered effluent cannot pass. The sieve structure comprises 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 1607 forms a channel for the effluent to flow starting from the inlet 1604 and around the sieve structure. The chamber is divided horizontally into two parts by a partition 1608. The partition 1608 has an opening on the other side of the internal dividing wall 1607. The combination of the opening and the lower part of the chamber below the partition 1608 provides a trap 1609 in which waste material can accumulate. The outlet 1605 is connected to a scoop 1610 which collects the filtered effluent that passes through the mesh.

[0076] Figure 16c is a cross-sectional view of separator unit 1600 along line A-A' in Figure 16a, where components of the filter pressure regeneration system are shown. A central vertical conduit 1611 provides washing fluid to a nozzle assembly. The nozzle assembly includes a propelling nozzle 1612 mounted on a rotatable hub 1613.

[0077] Figure 16d is a cross-sectional view of separator unit 1600 along line B-B' in Figure 16a, where components of the filter pressure regeneration system are shown. The nozzle assembly includes wash nozzles 1614a-d mounted on a rotatable hub 1613. The wash nozzles extend radially outward from the hub adjacent the filtered side of the sieve structure.

[0078] 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.

[0079] 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.

[0080] Figures 17-20 show how the pump-assisted embodiment of Figures 7-9 can be applied to a separator unit with a compound pressure regeneration system. The separator unit 1770 has an inlet, a cylindrical housing, and a sieve structure 1703. An outlet 1705 collects the filtered effluent. A portion of the filtered effluent is diverted into a conduit 1706 where it is pressurized by a pump 1707 and directed to a central vertical conduit 1708 which provides washing fluid to a nozzle assembly 1709.

[0081] 18a shows an embodiment suitable for locations below the water line and in which a portion of the filtered wastewater is also recirculated to regenerate filter pressure. The separator unit 1800 has an inlet 1801, a housing 1802, a sieve structure 1803, and an outlet 1804. All of the filtered effluent from the outlet 1804 is pumped out via a pump 1805. The pump 1805 is arranged to divert a portion of the filtered effluent back via conduit 1806 to a central vertical conduit 1807 which provides washing fluid to a nozzle assembly 1808. A restriction 1809 is provided in the pump outlet pipe 1810 to ensure that a sufficient amount of fluid is recirculated to the pressure regeneration system. Alternatively, the pump 1805 may have a single outlet as shown in FIG. 18b and a junction 1812 that diverts a portion of the filtered effluent to a conduit 1813 for recirculation into the pressure regeneration system and the remainder to a waste line. A restriction 1814 is provided to determine the percentage of the filtered effluent that is recirculated. Alternatively, the pump 1805 may have a single outlet as shown in FIG. 18b and an electronically controlled diversion valve that diverts a portion of the filtered effluent to a conduit 1813 for recirculation into the pressure regeneration system and the remainder to a waste line. These embodiments eliminate the need for separate recirculation and drain pumps. An air inlet 1815 may be provided in the conduit 1806, allowing air into the pressure regeneration system to enhance the cleaning effect of the jet of cleaning fluid against the filtered side of the sieve structure.

[0082] It may be advantageous to be able to separately control the drainage and pressure regeneration of the separator unit. Figure 19 shows one embodiment which allows this by providing two pumps, a drainage pump 1905 and a recirculation pump 1908. The separator unit has an inlet 1901 to a housing 1902 which supports a sieve structure 1903 which separates the inlet 1901 from the outlet 1904. The outlet 1904 has a conduit which leads to the drainage pump 1905. Also on the filtered side of the sieve structure is a washing fluid conduit 1907 which leads to a washing fluid pump 1908 and a further washing fluid conduit 1909 which feeds a washing nozzle assembly 1910. The drainage pump 1905 may be a positive displacement or centrifugal pump operating at 0.05-1 bar and 5-30 litres / min. The recirculation pump 1908 operates at 0.1-5 bar and 2-20 litres / min.

[0083] Figure 19b shows an alternative embodiment with separate wash fluid recirculation pump 1707 and drain pump 1910. The main advantage of this setup is that the drain pump can be sized to drain the filter only and does not need to run during the washer drain cycle. This reduces the power consumption, size and cost of the drain pump. A one-way valve 1911 is required to prevent the drain from recirculating back into the pump inlet.

[0084] Figure 19c shows an alternative embodiment with a single pump 1707 that can either supply wash water or drain the filter through the use of a diverter valve 1912. A one-way valve 1913 is required to prevent the drain water from recirculating back into the pump inlet.

[0085] Figure 19d shows an alternative embodiment of a single pump 1707 that can pump water to both the regeneration system 1708 and to drain simultaneously. The drain line has a constriction 1913 to force most of the water through the regeneration path. A one-way valve 1914 is required to prevent the drain from recirculating back to the pump inlet.

[0086] FIG. 20a shows an alternative embodiment of the separator unit using an air pump to assist in regeneration and drainage. An inlet 2001 is provided in a housing 2002 supporting a sieve structure 2003 separating the inlet 2001 from the outlet 2004. A conduit leads to a pump 2006 which pumps the filtered effluent to a further conduit 2007 which delivers the washing fluid to a washing nozzle assembly 2008. An air pump 2009 is connected to the further conduit 2007 and pumps air into the washing fluid system. The air enhances the cleaning effect of the washing fluid jet emitted from the washing nozzle 2008. The air pump can also be operated to push any remaining fluid in the tube connected to the outlet 2004 up to the water line, allowing this embodiment to be fitted below the water line. A one-way valve would need to be provided at the inlet (not shown) to prevent fluid being pushed back into the washing machine. The air pump also allows the filtered microplastics to be dried for easier handling when the unit is emptied, due to the force of the air compressing the captured effluent and reducing its water content.

[0087] Figure 20b shows an alternative nozzle assembly having a nozzle 2005 arranged to direct a flow of fluid 2010 towards a rotatable plate 2011. The plate has features 2012 arranged to deflect the flow of fluid outwardly towards a sieve structure 2013. The features 2012 are also arranged to rotate the plate such that the emitted fluid sweeps across the surface of the outlet side of the sieve structure, thus clearing debris on the other side.

[0088] A reservoir with a fluid sensor, such as a float switch, may be provided below the separator unit. The float switch detects when fluid is present in the reservoir. The float switch is arranged to control a pump to flush the sieve structure to regenerate the filter pressure. A pressure sensor may also be provided. Alternatively, a sensor may be provided at the inlet to detect when effluent backs up and this may be used to activate a pump to regenerate the filter pressure. The fluid sensor may be arranged to be activated when a particular level of fluid is detected and then activate either or both of the separator drain or pressure regeneration devices. Alternatively, the fluid sensor may be graduated, determining the level of fluid in the reservoir and such that drain is activated at a given level and regeneration is activated at a different fluid level. Another alternative is to use a combination of sensing systems to provide greater intelligence to the system. This may be a capacitance sensor on the filter inlet to identify the presence of fluid and a pressure sensor measuring across either the filter mesh, bypass, or both.

[0089] A bypass system may be provided to connect the inlet to the outlet. The bypass system 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 backflowing and causing overflow or affecting the performance of the washing machine or the drain cycle. The separator unit has an effluent inlet, a housing supporting the sieve structure, and an outlet. A bypass conduit connects the inlet to the outlet. A pressure-activated valve is located in the conduit. The pressure-activated valve opens when the pressure of the inlet relative to the outlet exceeds a certain predetermined value. Thus, if effluent backflows 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 the 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, so that when the pressure difference reaches a predetermined level, the valve is operated and the bypass is activated.

[0090] 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.

[0091] 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.

[0092] 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] 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 nozzles 2403a, 2403b arranged to extend over the height of the mesh. The nozzles can be flexible so that accumulated limescale can be easily broken up. The nozzles can also be made from a rigid plastic, which can be advantageous for manufacturability and recycling of the product components. 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.

[0095] 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.

[0096] 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.

[0097] 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.

[0098] 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.

[0099] 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.

[0100] 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.

[0101] 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.

[0102] 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.

[0103] 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.

[0104] A capacitive sensor is one type of fluid sensor, any other type such as a float switch can be used.

[0105] 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:

[0106] 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 help 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.

[0107] 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 but the drain pump may be operated.

[0108] Drain cycle: When the volume sensor indicates that the outflow at the input has stopped, the recirculation pump is operated after a delay that may be about 100 seconds to clean the mesh. This delay is adjustable. Immediately after, say, 2 seconds, the drain pump is turned on to drain the system. The recirculation pump is then turned off after, say, another 3 seconds, and then the drain pump is turned off after, say, 10 seconds.

[0109] stand-by: If the capacitance sensor is low, both the recirculation pump and the drain pump can be turned off.

[0110] 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.

[0111] 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.

[0112] 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 needed. When fluid is being pumped through the filter and the pressure sensor is low, the recirculation pump is not run but the drain pump is 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.

[0113] 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.

[0114] 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. Furthermore, by replacing the existing filters with the advanced filtration technology disclosed herein, different washer pumps can be used together, operating at higher efficiency.

[0115] 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.

[0116] The separator housing can be opened to empty the trap when the effluent has been drained.

[0117] To avoid airlocks, an opening may be provided at the top of the sieve structure.

[0118] To avoid all the waste water being siphoned off from the washing machine, an air inlet may be provided at the inlet of the separator.

[0119] 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 or cleaned by the user and then reused.

[0120] 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.

[0121] 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.

[0122] 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.

[0123] 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.

[0124] 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.

[0125] 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.

[0126] 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.

[0127] In both systems, roadside runoff, i.e. surface water from the road, is discharged into the environment.

[0128] 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.

[0129] 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.

[0130] 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 (1702) having an inlet (1701) and an outlet (1705); a sieve structure (1703) forming a permeable barrier between the inlet and the outlet for filtering the fluid, thereby having an inlet side for unfiltered fluid and an outlet side for filtered fluid; a pump (1707) in fluid communication with the chamber, the separator further comprising a filter pressure recovery device (1709) for removing filtered material from the sieve structure; the filter pressure regeneration device comprises a conduit and a nozzle assembly having at least one cleaning jet located at the outlet side of the sieve structure for directing fluid toward the sieve structure, the pump being arranged to recirculate the filtered fluid to the conduit of the filter pressure regeneration device; A separator, wherein the sieve structure has a circular cross-section, a channel is formed between the chamber and the sieve structure, the channel extends circumferentially around the sieve structure, and the separator is configured such that, in use, the fluid is guided to pass circumferentially around the channel from the inlet.

2. 2. A separator according to claim 1, wherein the pump is a water pump also arranged to drain the separator or a separate pump is provided for draining the separator.

3. 2. The separator of claim 1, wherein a restriction (1809) is provided in a conduit downstream of the pump, the aperture of the restriction being set to ensure that a preset amount of filtered fluid is recirculated to the filter pressure regeneration device and that an amount of the filtered fluid is drained.

4. 2. The separator of claim 1, wherein a conduit between said pump and said filter pressure regeneration device is provided with a vent (1805) for introducing air into said conduit.

5. 10. The separator of claim 1, further comprising an air pump (2009) located between the pump and the filter pressure regeneration device to introduce air into the conduit and to drain the separator.

6. The separator of claim 1 , wherein the pump is a positive displacement pump.

7. The separator of claim 1 , wherein the pump is a centrifugal pump.

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

9. 2. The separator of claim 1, wherein the nozzle assembly is rotated by propelling nozzles (1503a, 1503b) arranged to direct a fluid flow having a vector that is tangential to the circumference of the sieve structure or offset from the central axis.

10. 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.

11. 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.

12. A washing machine comprising the separator according to any one of claims 1 to 11.

13. A method for operating a separator according to any one of claims 1 to 11, comprising the steps of: filtering the fluid through a sieve structure; operating a pump to pressurize the filtered fluid.

14. The method of claim 13 , wherein the pump is operated to drain the separator.

15. 14. The method of claim 13, wherein the pump is operated to recirculate the filtered fluid to a pressure regeneration device, the pressure regeneration device being arranged to spray a cleaning fluid onto a filtered side of the sieve structure to remove debris from an unfiltered side of the sieve structure.

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