WO2021229398A2 - Micro/nano bubble generator and/or system - Google Patents

Abstract

A system for introducing micro and/or nano bubbles into liquid includes a liquid reservoir, at least one generator located within the reservoir and a pump arranged to urge liquid from within the reservoir via a first line towards the at least one generator. The at least one generator has a first inlet and primary and secondary ports and pressurized liquid that arrives via the first line is arranged to enter the at least one generator via the first inlet to swirl within the generator and produce suction urging a second fluid to be drawn into the generator via at least one of the primary and secondary ports to form treated liquid.

Description

MICRO/NANO BUBBLE GENERATOR AND/OR SYSTEM TECHNICAL FIELD [001] Embodiments of the invention relate to a micro/nano bubble generator and/or system, in particular tuned for enhancing generation of minute sized bubbles and/or mixtures of various substances. BACKGROUND [002] Micro or Nano bubbles can be formed using a variety of gaseous and can be injected into various types of liquid. Due to their size, such bubbles exhibit unique properties that improve numerous physical, chemical, and biological processes. [003] A Micro or Nano bubble generator is a device that mixes water and a gas to produce such bubbles. Various types of generators exist, such as a gas-water circulation type, a gas-water pressurization-decompression type (etc.). [004] In a gas-water circulation type, gas is introduced into a water vortex and the gas bubbles are formed by breaking the vortex. In the pressurized dissolution method, gas under pressure is dissolved in water to form a saturated solution, such that when the water is depressurized the gas escapes to forms the required bubbles. SUMMARY [005] The following embodiments and aspects thereof are described and illustrated in conjunction with systems, tools and methods which are meant to be exemplary and illustrative, not limiting in scope. [006] In an embodiment there is provided a system for introducing micro and/or nano bubbles into liquid, and comprising: a liquid reservoir, at least one generator located within the reservoir and a pump arranged to urge liquid from within the reservoir via a first line towards the at least one generator, the at least one generator comprising a first inlet and primary and secondary ports, wherein pressurized liquid arriving via the first line is arranged to enter via the first inlet a swirl chamber located within the at least one generator to swirl within the swirl chamber and produce suction urging one or more second fluids to be drawn into the swirl chamber via at least one of the primary and secondary ports to form treated liquid, wherein treated liquid is arranged to exit the at least one generator back into the reservoir via the primary and secondary ports, [007] In one aspect, the generator comprising a soothing tooth formed on an inner face of the swirl chamber adjacent to where the first inlet enters the swirl chamber, and the soothing tooth being arranged to define a path directing flow of liquid passing over the tooth to blend in with incoming flow of liquid arriving via the first inlet. [008] In another aspect, either independent or combinable with other aspects, the generator comprises an insert member at least at one of its primary and secondary ports that is made from a material that is different to that in surrounding material of the body of the generator, and fluid entering or exiting a generator via a port comprising an insert member is arranged to pass through the insert member. [009] In yet another aspect, either independent or combinable with other aspects, the system further comprising a second line arranged at its entry to receive pressurized liquid arriving from the pump and emit the liquid at its end at a substantially lower pressure, and the second line having a length ‘L’ that is at least about nearly two orders of magnitude greater than its internal diameter ‘D’ (i.e. ‘L’ ≥ 75 × ‘D’ or more preferably L’ ≥ 100 × ‘D’). [010] In yet even a further aspect, either independent or combinable with other aspects, the system comprises a nipple at a downstream end of a fluid inline leading fluid towards the primary and/or secondary ports, wherein the nipple being coupled to the generator adjacent a port of the generator and a distance of a tip of the nipple through which a second fluid is ejected towards the generator is adjustable in relation to the port of the generator. [011] In addition to the exemplary aspects and embodiments described above, further aspects and embodiments will become apparent by reference to the figures and by study of the following detailed descriptions. BRIEF DESCRIPTION OF THE FIGURES [012] Exemplary embodiments are illustrated in referenced figures. It is intended that the embodiments and figures disclosed herein are to be considered illustrative, rather than restrictive. The invention, however, both as to organization and method of operation, together with objects, features, and advantages thereof, may best be understood by reference to the following detailed description when read with the accompanying figures, in which: [013] Fig. 1 schematically shows an embodiment of a micro/nano bubble system in accordance with the present invention; [014] Fig. 2 schematically shows a diagram of an embodiment of a micro/nano bubble system generally similar to that in Fig.1; [015] Figs. 3A to 3C schematically show: perspective-side, exploded and side views, respectively, of an embodiment of a micro/nano bubble generator possibly used in any one of the systems of Figs.1 and 2; and [016] Fig. 4 schematically shows another embodiment of a micro/nano bubble system in accordance with the present invention. [017] It will be appreciated that for simplicity and clarity of illustration, elements shown in the figures have not necessarily been drawn to scale. For example, the dimensions of some of the elements may be exaggerated relative to other elements for clarity. Further, where considered appropriate, reference numerals may be repeated within the figures to indicate like elements. DETAILED DESCRIPTION [018] Attention is first drawn to Figs. 1 and 2 illustrating an embodiment of a micro/nano bubble system 10 of the present invention, with a generator 12 of the system being visible in Fig. 2. System 10 in this example includes a water reservoir 14, such as a water tank in this example that has a main inlet 1 and a main outlet 2. It is noted that in other embodiments, water reservoir 14 may take other forms such as a natural reservoir (or the like). [019] Main inlet 1 may be arranged to communicate liquid into water reservoir 14 e.g. from a consumer or a liquid source and outlet 2 may be arranged to communicate treated liquid from water reservoir 14 e.g. to a consumer. The system in addition includes a pump 16 for pumping water out of the reservoir via an intake 18 and directing the removed water back via a first line 20 into a first inlet 121 of the generator and via second line 22 back into the reservoir. [020] The system also includes a fluid inline 24 for directing fluid towards a primary port 122 of the generator, and generator 12 may be arranged to include also a secondary port 123 here at an opposing lateral side of the generator. In the shown example, second line 22 is seen branching away from first line 20, however different arrangements may also be available where second line 22 may e.g. start directly at pump (or the like). [021] During operation of the system, the pump forces substances removed from the reservoir along first line 20 into the generator via its first inlet 121. Fluid (e.g. air, ozone, oxygen, nitrogen, fertilizer, chlorine, flocculants, coagulants, CO2, or the like) may be urged through fluid inline 24 into the generator via its primary port 122 due to suction ignited via vacuum created within the generator, e.g. by a swirling motion of water (as in the generator example described herein). [022] In certain embodiments, fluids such as those mention above (e.g. air, ozone, oxygen, nitrogen, fertilizer, chlorine, flocculants, coagulants, CO2, or the like), may be also urged through a fluid inline (not shown) such as 24, into the generator via its secondary port 123 due to said similar suction that is ignited via vacuum created within the generator, e.g. by a swirling motion of water (as in the generator example described herein). [023] In embodiments where fluids are arranged to be urged both into the primary and secondary ports 122, 123 – a first fluid urged to be sucked into the primary port 122 may be arranged to be different than a second fluid that is urged to be sucked into the secondary port 123 – so that a resulting mixture of such different fluids may be formed within the generator to be then emitted back into the reservoir. [024] Such fluid(s) being supplied into the primary port 122 (and possibly also the secondary port 123) of the generator e.g. via fluid inline 24 - may be treated (e.g., cooled) and/or may be supplied from containers (not shown) where they may be stored or may be sucked from the ambient environment in the example of air being the substance of such fluid. [025] Interaction between the incoming gas and the swirling water within the generator is arranged to produce a treated liquid with micro/nano bubbles, which may then be ejected into the reservoir via both the primary and secondary ports 122, 123. [026] Section A-A at the lower right-hand side of Fig. 2 (that represents a cross sectional view taken along a central axis of a port, in this example primary port 122, of the generator) - indicates opposing fluid flows that may exist at a port of the generator. As seen, on the one hand internal suction from within the generator may draw fluid (as indicated by the ‘dashed’ arrow) to flow into the generator via the port, while on the other hand an opposing directed fluid flow of treated liquid from within the generator may be urged to flow outwards via the port (as indicated by the ‘dotted’ arrows). [027] In at least certain embodiments, enhancement of generation of minute sized bubbles may be facilitated via channeling a portion of the water removed by the pump via second line 22, possibly back into the reservoir or elsewhere (e.g. to an external consumer). [028] Second line 22 may be arranged to apply so-called ‘relaxation’ to pressurized liquid supplied via pump 16 so that the liquid pressure exiting second line 22 may be substantially lower (e.g. substantially equal to pressure in the ambient environment or the like) – possibly promoting formation of reduced sized micro/nano bubbles. [029] Such ‘relaxation’ may be obtained by arranging second line 22 to be substantially long (e.g. in a non-binding example longer than first line 20) and by arranging second line 22 to have a relative small internal diameter (e.g. again in a non-binding example smaller in diameter in relation to first line 20). [030] For example, a length of second line 22 may typically be more than about 10 meters e.g. more than about 20 meters (for example about 100 or 600 meters), while an internal diameter of second line 22 may typically be about 3, 4, 12 millimeters (or the like). [031] Thus, in a broad definition - a length ‘L’ of second line 22 may be defined as being at least about nearly two orders of magnitude greater than its internal diameter ‘D’ in order to provide such optimal ‘relaxation’ (i.e. ‘L’ = at least 75 or 100 times ‘D’ or ‘L’ ≥ 75 × ‘D’ or more preferably L’ ≥ 100 × ‘D’). [032] Attention is drawn to Figs. 3A to 3C illustrating an embodiment of a generator 120 according to the present invention. Generator 120 includes a first inlet 1201 and primary and secondary ports 1202, 1203. In the exploded view of Fig. 3B, the first inlet 1201 is shown leading into a core 51 of the generator, while the primary and secondary ports 1202, 1203 are shown being formed, respectively, in primary and secondary members 52, 53 of the generator that are formed on both sides of the core sandwiching the core there between. [033] The core has an inner spacing 1204 that together with inner sides (possibly dome shape inner sides) of the primary and secondary members 52, 53; defines a swirl chamber 88 of the generator (best seen in Fig. 3C). Inlet 1201 may be arranged to tangentially lead liquid into swirl chamber 88 to form a trajectory that generally follows a peripheral inner face of the chamber. The entering water swirls about a center of the chamber where a primary vacuum zone 91 can be formed, while being urged to exit the chamber at the primary and secondary ports 1202, 1203. [034] In an embodiment, swirl chamber 88 may be arranged to include a soothing tooth 77 formed on the inner face of the chamber. In this example, soothing tooth 77 may be formed adjacent to where first inlet 1201 enters into the swirl chamber 88, and may be arranged to define a path along the chamber’s inner face directing the flow of water passing over the tooth to blend in with the incoming flow of incoming water into the chamber, and by that enhance laminar flow within the chamber. [035] Liquid flow within the swirl chamber accordingly swirls in a generally downstream rotational direction R about a center of the chamber. Thus, in the example shown, soothing tooth 77 may be defined as being located immediately upstream to where liquid enters the swirl chamber. The path directing water flow passing over the tooth to blend in with the incoming flow of water entering a swirl chamber can thus be defined as being formed by an inner side 27 of the tooth facing radially into the chamber, being curved radially inwards so that a downstream tip 29 of the tooth is radially inwardly displaced relative to a remainder major portion 25 of the chamber’s inner face that generally has a constant internal diameter D. [036] In an embodiment, a tip 29 at a downstream end of the tooth may be chamfered in order to form a secondary vacuum zone 92 that may increase formation of bubbles and/or blending of substances within the swirl chamber. [037] Attention is drawn to section V in Fig. 2 illustrating a nipple 1221 that is formed at an end of fluid inline 24 and is arranged to lead fluid in this example towards primary port 122. As aforementioned, in embodiments where an additional fluid line (not shown in the figures) leads fluid towards the other secondary port 123 – a generally similar nipple as seen with respect to nipple 1221 may also be formed. [038] The nipple may be arranged to adjust the distance at which fluid received by the fluid line is released towards its respective port. In the shown example, such adjustment may be accomplished by forming nipple with an external thread that is threaded through a support 17 that supports the nipple opposite its associated port. [039] In certain embodiments, an insert member 19 may be formed at one or more of the ports 122, 123 in order to reduce or substantially eliminate erosion at the ports due to e.g. the treated liquid exiting the generator via the ports. Possibly, the body of generator 12 may be formed from a first type material (e.g. plastic material such as PVC or the like), while the insert member 19 may be formed a second type of material, e.g. a more resistant material e.g. to erosion and/or oxidization. [040] For example, insert member 19 may be formed from stainless steel, ceramics (or the like) that may be more resistance to erosion and/or oxidization of incoming or outgoing fluid(s) passing there through, such as ozone, oxygen (etc.). It is noted, that certain generator embodiments may be envisioned having only one of the insert members at one of the ports. [041] Attention is drawn to the lower left-hand side of Fig. 2 illustrating a possible design of such an insert member 19. The left illustration shows a side view of the insert member illustrating its generally coned formation that leads towards an aperture 191 through which fluid enters and exits the generator at a port. The right illustration shows a top view of the insert member. Such insert member may be over-molded within the body of the generator. [042] Such reduction or elimination of erosion by the material of choice of the insert member - may be aimed, inter alia, at maintaining the size (e.g. diameter) of the aperture 191 of the insert member – so that optimal treatment of liquid within the generator may be maintained during operation of the generator. [043] Attention is drawn to Fig. 4 illustrating an embodiment of a micro/nano bubble system 100. System 100 in this example can be seen including a water reservoir 140 having a main inlet 1 and a main outlet 2. Inlet 1 may be arranged to communicate liquid into water reservoir 140 e.g. from a consumer or a liquid source and outlet 2 may be arranged to communicate treated liquid from water reservoir 140 e.g. to a consumer. [044] The system in addition includes a plurality of generators 12000 (here three generators) located within the liquid in the reservoir and attached to a manifold 77. The system in addition includes a pump 160 for pumping water out of the reservoir via an intake 180 and directing the removed water/liquid back via a first line 20 towards manifold 77, from where the liquid is directed into a respective first inlet 12001 of each one of the generators. [045] System 100 in this example includes a second line 22 that here branches away from the first line 20, however in certain cases second line 22 may branch off directly from pump 160. In this example, second line 22 is seen branching away from the system, e.g. to a consumer – however in certain cases second line 22 may be directed back into reservoir 140. [046] In at least certain embodiments, enhancement of generation of minute sized bubbles may be facilitated via channeling a portion of the water removed by the pump via second line 22, possibly back into the reservoir or elsewhere (e.g. to an external consumer). [047] Second line 22 may be arranged to apply so-called ‘relaxation’ to pressurized liquid supplied via pump 160 so that the liquid pressure exiting second line 22 may be substantially lower (e.g. substantially equal to pressure in the ambient environment or the like) – possibly promoting formation of reduced sized micro/nano bubbles. [048] Such ‘relaxation’ may be obtained by arranging second line 22 to be substantially longer than first line 20 (as exemplified above with respect to previous system 10); e.g. arranging second line 22 to be more than about 20 meters in length, for example up to about 100 meters in length – while first line 20 being up to a few meters in typical conditions, and not more than about 10 meters if needed. In addition or alternatively, such ‘relaxation’ may be obtained by arranging second line 22 (as exemplified above with respect to previous system 10) to have an internal diameter that is substantially smaller (e.g. about 3 or 4 millimeter internal diameter) than a diameter of first line 20 (e.g. about 25 millimeter internal diameter). [049] The system also includes a plurality fluid in-lines 24 each directing fluid towards a primary port 12002 of a respective one of the generators, and each generator 12000 may be arranged to include also a secondary port 12003. [050] During operation of the system, the pump forces substances removed from the reservoir along first line 20 into the generators via their first inlets 12001. Fluid (e.g. air, ozone, oxygen, nitrogen, fertilizer, chlorine, flocculants, coagulants, or the like) may be urged through the fluid in-lines 24 into the respective generators via their primary port 12002 due to suction ignited via vacuum created within each generator, e.g. by a swirling motion of water (as in the generator example described herein). [051] Such fluids being supplied via fluid in-lines 24 to the generators may originate from one or more external containers (here an example of one container 99 coupled to all lines is illustrated). Incoming fluid via in-lines 24 may be treated (e.g., cooled) and/or may be accordingly supplied from containers (as here one seen) where they may be stored or may be sucked from the ambient environment in the example of air being the substance of such fluid. [052] Interaction between the incoming gas and the swirling water within the generator is arranged to produce micro/nano bubbles, which may then be ejected into the reservoir via both the primary and secondary ports 12002, 12003. [053] System 100 illustrates use of several generators, where possibly at least some of which may be arranged to receive different incoming fluids. Thus in an aspect of the present invention, system 100 may be seen exemplifying mixing of several different fluids, each via a generator aimed at increasing presence of micro/nano bubbles therein – to thereby form a mixture of such treated fluid – to be supplied to a consumer. [054] In the description and claims of the present application, each of the verbs, “comprise” “include” and “have”, and conjugates thereof, are used to indicate that the object or objects of the verb are not necessarily a complete listing of members, components, elements or parts of the subject or subjects of the verb. [055] Further more, while the present application or technology has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered illustrative or exemplary and non- restrictive; the technology is thus not limited to the disclosed embodiments. Variations to the disclosed embodiments can be understood and effected by those skilled in the art and practicing the claimed technology, from a study of the drawings, the technology, and the appended claims. [056] In the claims, the word “comprising” does not exclude other elements or steps, and the indefinite article “a” or “an” does not exclude a plurality. A single processor or other unit may fulfill the functions of several items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures can not be used to advantage. [057] The present technology is also understood to encompass the exact terms, features, numerical values or ranges etc., if in here such terms, features, numerical values or ranges etc. are referred to in connection with terms such as “about, ca., substantially, generally, at least” etc. In other words, “about 3” shall also comprise “3” or “substantially perpendicular” shall also comprise “perpendicular”. Any reference signs in the claims should not be considered as limiting the scope. [058] Although the present embodiments have been described to a certain degree of particularity, it should be understood that various alterations and modifications could be made without departing from the scope of the invention as hereinafter claimed.

Claims

CLAIMS: 1. A system for introducing micro and/or nano bubbles into liquid, and comprising: a liquid reservoir, at least one generator located within the reservoir and a pump arranged to urge liquid from within the reservoir via a first line towards the at least one generator, the at least one generator comprising a first inlet and primary and secondary ports, wherein pressurized liquid arriving via the first line is arranged to enter via the first inlet a swirl chamber located within the at least one generator to swirl within the swirl chamber and produce suction urging one or more second fluids to be drawn into the swirl chamber via at least one of the primary and secondary ports to form treated liquid, wherein treated liquid is arranged to exit the at least one generator back into the reservoir via the primary and secondary ports, and wherein the generator comprising a soothing tooth formed on an inner face of the swirl chamber adjacent to where the first inlet enters the swirl chamber, and the soothing tooth being arranged to define a path directing flow of liquid passing over the tooth to blend in with incoming flow of liquid arriving via the first inlet.

2. The system of claim 1, wherein liquid swirl within the swirl chamber is in a generally downstream rotational or helical direction about a center of the swirl chamber and the soothing tooth is located immediately upstream to where the first inlet enters, possibly tangentially, the swirl chamber.

3. The system of claim 2, wherein an inner face of the soothing tooth facing into the swirl chamber curves radially inwardly along a curvature that is different to a curvature of the inner face of the swirl chamber that is outside of the soothing tooth.

4. The system of claim 1, wherein the at least one generator is a plurality of generators.

5. The system of claim 4, wherein each one of the generators being arranged to receive fluid via a different fluid inline.

6. The system of claim 5, wherein at least some of the fluids entering different generators are different.

7. The system of claim 1, wherein the one or more second fluid entering a generator is any one of: air, ozone, oxygen, nitrogen, fertilizer, chlorine, flocculants, coagulants, CO2.

8. The system of claim 1, wherein the one or more second fluid is communicated towards the generator via a fluid inline.

9. The system of claim 8 and comprising a nipple at a downstream end of the fluid inline, wherein the nipple being coupled to the generator adjacent a port of the generator and a distance of a tip of the nipple through which a second fluid is ejected towards the generator is adjustable in relation to the port of the generator.

10. The system of claim 1, wherein the reservoir comprising a main inlet and a main outlet, and treated liquid exiting via the main outlet is arranged to flow towards a consumer suited for utilizing the treated liquid.

11. The system of claim 1 and comprising a second line arranged at its entry to receive pressurized liquid arriving from the pump and emit the liquid at its end at a substantially lower pressure, possibly generally equal to pressure at the ambient environment.

12. The system of claim 11, wherein the second line being arranged to branch off from the first line or branch off directly from the pump.

13. The system of claim 12, wherein a length ‘L’ of the second line being about nearly two orders of magnitude greater than its internal diameter ‘D’.

14. The system of claim 1, wherein the at least one generator comprises an insert member at least at one of its primary and secondary ports, and wherein the insert member being made from a material that is different to that in surrounding material of the body of the generator.

15. The system of claim 14, wherein fluid entering or exiting a generator via a port comprising an insert member is arranged to pass through the insert member.

16. A generator for introducing micro and/or nano bubbles into a liquid and comprising: a first inlet and primary and secondary ports, the generator comprising an internal swirl chamber and liquid entering the swirl chamber via the first inlet is arranged to swirl and produce suction urging one or more second fluids to be drawn into the generator via at least one of the primary and secondary ports to form treated liquid, wherein treated liquid is arranged to exit the generator via the primary and secondary ports, and wherein the generator comprising a soothing tooth formed on an inner face of the swirl chamber adjacent to where the first inlet enters the swirl chamber, and the soothing tooth being arranged to define a path directing flow of liquid passing over the tooth to blend in with incoming flow of liquid arriving via the first inlet.

17. The generator of claim 16, wherein liquid swirl within the swirl chamber is in a generally downstream rotational or helical direction about a center of the swirl chamber and the soothing tooth is located immediately upstream to where the first inlet enters the swirl chamber.

18. The generator of claim 17, wherein an inner face of the soothing tooth facing into the swirl chamber curves radially inwardly along a curvature that is different to a curvature of the inner face of the swirl chamber that is outside of the soothing tooth.

19. The generator of claim 16 and comprising an insert member at least at one of its primary and secondary ports, wherein the insert member being made from a material that is different to that in surrounding material of the body of the generator, and fluid entering or exiting a generator via a port comprising an insert member is arranged to pass through the insert member.

20. The generator of claim 19, wherein the material of the insert member is harder and/or more erosion resistant than the surrounding material of the body of the generator.

21. A generator for introducing micro and/or nano bubbles into a liquid and comprising: a first inlet and primary and secondary ports, the generator comprising an internal swirl chamber and liquid entering the swirl chamber via the first inlet is arranged to swirl and produce suction urging one or more second fluids to be drawn into the generator via at least one of the primary and secondary ports to form treated liquid, wherein treated liquid is arranged to exit the generator via the primary and secondary ports, and the generator comprising an insert member at least at one of its primary and secondary ports that is made from a material that is harder and/or more erosion resistant than that in surrounding material of the body of the generator, and fluid entering or exiting the generator via a port comprising an insert member is arranged to pass through the insert member.

22. A system for introducing micro and/or nano bubbles into liquid, and comprising: a liquid reservoir, at least one generator located within the reservoir and a pump arranged to urge liquid from within the reservoir via a first line towards the at least one generator, the at least one generator comprising a first inlet and primary and secondary ports, wherein pressurized liquid arriving via the first line is arranged to enter via the first inlet a swirl chamber located within the at least one generator to swirl within the generator and produce suction urging one or more second fluids to be drawn into the generator via at least one of the primary and secondary ports to form treated liquid, wherein treated liquid is arranged to exit the at least one generator back into the reservoir via the primary and secondary ports, and wherein the at least one generator comprises an insert member at least at one of its primary and secondary ports that is made from a material that is different to that in surrounding material of the body of the generator, and fluid entering or exiting a generator via a port comprising an insert member is arranged to pass through the insert member.

23. A system for introducing micro and/or nano bubbles into liquid, and comprising: a liquid reservoir, at least one generator located within the reservoir and a pump arranged to urge liquid from within the reservoir via a first line towards the at least one generator, the at least one generator comprising a first inlet and primary and secondary ports, wherein pressurized liquid arriving via the first line is arranged to enter via the first inlet a swirl chamber within the at least one generator to swirl within the generator and produce suction urging one or more second fluids to be drawn into the generator via at least one of the primary and secondary ports to form treated liquid, wherein treated liquid is arranged to exit the at least one generator back into the reservoir via the primary and secondary ports, and wherein the system further comprising a second line arranged at its entry to receive pressurized liquid arriving from the pump and emit the liquid at its end at a substantially lower pressure, and the second line having a length ‘L’ that is at least about nearly two orders of magnitude greater than its internal diameter ‘D’.

24. A system for introducing micro and/or nano bubbles into liquid, and comprising: a liquid reservoir, at least one generator located within the reservoir and a pump arranged to urge liquid from within the reservoir via a first line towards the at least one generator, the at least one generator comprising a first inlet and primary and secondary ports, wherein pressurized liquid arriving via the first line is arranged to enter via the first inlet a swirl chamber located within the at least one generator to swirl within the swirl chamber and produce suction urging one or more second fluids to be drawn into the swirl chamber via at least one of the primary and secondary ports to form treated liquid, wherein treated liquid is arranged to exit the at least one generator back into the reservoir via the primary and secondary ports, and wherein the one or more second fluid is communicated towards the generator via a fluid inline, and the system comprising a nipple at a downstream end of the fluid inline, and the nipple being coupled to the generator adjacent a port of the generator and a distance of a tip of the nipple through which a second fluid is ejected towards the generator is adjustable in relation to the port of the generator.