Bubble size is an economic variable.
Nano Bubble Oxidation Technology, written for the person who will be asked to defend it in a technical review.
Gas utilisation is the whole argument. A coarse-bubble diffuser is a magnificent machine for moving gas from a cylinder to the atmosphere by way of some water, and the water gets whatever the transit did not claim. On a large volume that fraction is small, which is why conventional aeration scales by adding power rather than by adding cleverness.
Below roughly a micron the accounting changes. Buoyancy no longer governs the bubble, so it does not simply rise and vent. A negative surface charge — the literature puts oxygen nanobubbles somewhere around −34 to −45 mV — keeps neighbouring bubbles from coalescing into large ones that would. And subdividing gas multiplies the interface it presents far faster than it consumes the volume, so the same cylinder now meets the water across an enormously greater area.
One published measurement carries the commercial case. Work in Science of the Total Environment on nanobubble aeration recorded a gas–liquid mass transfer coefficient about eleven times higher than conventional bubbles delivering the same gas volume.
Read that eleven as the high end of a band rather than a constant. Other comparisons in the same literature come in materially lower, which is why a skid is specified against the bottom of the range: a stage costed on elevenfold and a stage costed on the low end are two different capital decisions, and only one of them survives a season.
Even at the bottom of that band, it is the difference between equipment that has to be built into a site and equipment that can be driven to one.
What the stage actually consists of
- Read Nothing is dosed before the water is characterised. Temperature, conductivity, pH, dissolved oxygen, turbidity and organic load, taken at the point of treatment rather than from last year's file. Organic load is the one that matters most commercially, because it is what consumes oxidant without producing a result.
- Select the gas Oxygen where the fault is a deficit. Ozone where the fault is a load. A blend where it is both, which is more often than operators expect. On a contracted programme the gases sit inside the service rather than becoming a procurement exercise for your team.
- Shear In-line generation into the sub-micron range. Get this wrong and you have built a very expensive coarse-bubble diffuser, which is the failure mode most of this category shares.
- Place the contact Into the layer or the section of circuit that carries the fault. Treating the top metre of a stratified reservoir in August is decoration; the shortfall is at the bottom and that is where the treated water has to arrive. On a saline duty the same logic runs at the intake instead — the draw comes off the depth the fault is sitting in.
- Hold the standard The discharge standard is fixed before the stage runs, and the stage is operated to meet it rather than to the throughput anybody would prefer. Inline instruments govern the treatment as it happens and can cut the oxidant on their own, and a defined set of stop conditions halts the work outright. Those instruments cannot see a stable end product such as bromate, so independent laboratory analysis confirms that separately — the two are complementary and neither stands in for the other.
- Log it The same parameters, on the same schedule, after the pass as before it. The log is a deliverable in its own right, because that is what your regulator and your auditor will actually read.
Fresh against saline
Two water types, two sets of limits.
This distinction matters more here than anywhere else in the family, because one skid can be on a reservoir in March and an intake approach in June.
Bromide is the reason. In fresh water there is not enough of it to change anything, and an oxidative stage is governed by organic load and whatever the receiving environment will tolerate. Seawater and brackish groundwater are different: ozone goes after bromide roughly eighty-three times harder than chloride, and the hypobromite that follows can convert to bromate.
Bromate is also stable. You cannot quench it once it exists, and you cannot dilute your way into compliance with it — which is why treating it as something to detect afterwards was always the weaker answer. So on saline duty it is controlled at source, before it forms, and the water leaving the stage is held at or below 10 micrograms per litre. That value is drinking-water-derived and it is applied directly to the discharge, with no credit taken for whatever the receiving water would have done to it afterwards.
A failed batch does not go back into your water. It is held, and it leaves with us. That is a sentence your regulator can repeat to somebody else without qualifying it, which is most of what a compliance file is for.
One process detail worth having, because a reviewing chemist will ask. Where residual oxidant needs quenching it is quenched with hydrogen peroxide rather than with a sulfur reductant, because a sulfur reductant exerts oxygen demand and would eat the oxygen enrichment the discharge exists to deliver.
| Parameter | Fresh duty | Saline or brackish duty |
|---|---|---|
| Oxygenation | Unchanged — transfer physics is the same | Unchanged — transfer physics is the same |
| Governing limit on oxidation | Organic load, and what the receiving water will take | A discharge standard met at the outlet, bromate at or below 10 µg/L |
| Live monitoring | Dissolved oxygen, turbidity, organic load | The same, plus inline oxidant residual and pH, with independent laboratory confirmation of the discharge |
| Typical assets | Reservoirs, amenity lakes, lagoons, cooling and process circuits | Intake approaches, discharge fields, port basins, brackish sources |
Two agency validations, and whose equipment they used
In September 2018 NOAA's National Centres for Coastal Ocean Science published a validation of an ozone nanobubble aeration system run on an eight-acre pond near Fort Myers Beach, Florida. Algae eliminated inside 48 hours. Reoxygenation handled properly, and no apparent harm to the aquatic life in the pond.
Two years later, NCCOS-affiliated testing under a cooperative agreement put a commercial nanobubble ozone system through a ballast water duty. It was found highly effective against algae, bacteria and motile zooplankton, and the receiving-water organisms showed no statistically significant adverse residual toxicity.
Both are real, independent and directly relevant to what this stage does. Neither names Fluid Nano and neither names Alarivean. The 2018 release names a system called NABAS. The 2020 release names a technology abbreviated NBOT, for Nanobubble Ozone Technology, tested with the American Marine University Research Institute — the same four letters this network uses for Nano Bubble Oxidation Technology, and a different party. Both releases establish that the approach clears what it is aimed at without wrecking the receiving water. Neither is a test of Fluid Nano equipment.
Alarivean's own field record here is one permit. Florida DEP issued FLOA00062 in September 2024 for a red tide mitigation field trial, documented separately by the Sarasota Bay Estuary Programme and by the Florida nonprofit START. What FLOA00062 shows is that a regulator holding jurisdiction over those waters read the proposal and permitted bounded field work under it. Efficacy in open water is a separate question and the permit does not answer it.
The estuary programme put technical support into the application and kept its money out, and it wants to be the party holding the instruments when open-water work is finally measured, so that anything endorsed past the bay rests on its readings rather than the operator's. Alarivean wants the same arrangement. Nothing has been published in either direction on open-water efficacy for this class of treatment.
Two open parameters
Radical chemistry. Whether nanobubbles themselves generate hydroxyl radicals is unresolved in the literature. Moleaer and Arizona State University reported reactive oxygen species, hydroxyl radicals among them, from injected nanobubbles in 2020; three years later a controlled study by Chae, Kim, Kim and Fortner in ACS ES&T Engineering found generation minimal at best under the ambient conditions tested. The commercial case rests on gas transfer and a metered oxidant dose, neither of which depends on the answer.
Scale. Every independent validation of this technology class is pond-sized or tank-sized. A three-hundred-hectare reservoir, a live condenser circuit and half a kilometre of open intake approach are three different engineering problems, and none of them is an eight-acre pond in Florida. Closing that distance on your water, before capacity is committed, is the entire function of a calibration run.
The papers and releases behind this stage
- NOAA National Centres for Coastal Ocean Science — Nanobubble technology validated for remediation of harmful freshwater algal blooms, 26 September 2018.
- NOAA National Centres for Coastal Ocean Science — Nanobubble ozone technology shown to safely eliminate invasive species in ballast water, 1 July 2020.
- Science of the Total Environment — Mass transfer of nanobubble aeration and its effect on biofilm growth.
- Chae, Kim, Kim & Fortner — Reactive oxygen species generation from nanobubbles, ACS ES&T Engineering, 2023.
- Springer — Nanobubble stability and zeta potential.
- Ozone: Science & Engineering — Bromate formation in seawater ozonation.
- Sarasota Bay Estuary Programme and START (Solutions To Avoid Red Tide) — public documentation of FDEP permit FLOA00062, 2024.
Questions we get asked
Straight answers
Does anything join my chemical inventory?
No. The working input is gas — oxygen, ozone or a blend — conditioned on site and delivered as sub-micron bubbles. Nothing to store, nothing to reconcile against a second chemistry, nothing left over at the end of a run.
Can you give me a performance percentage for my cooling loop?
No. There is no published figure for this duty on a circuit like yours, and the answer moves with make-up chemistry, metallurgy, load profile and the programme you already run.
A bounded run against your own fouling indicators, with the failure condition agreed in advance, produces the only number that will go in writing.
Does the chemistry change between my reservoir and my seawater intake?
The oxygenation does not. The oxidation does, and bromide is why. Fresh water has too little of it to matter. Seawater and brackish groundwater have enough that ozone will find it roughly eighty-three times faster than it finds chloride, and the hypobromite produced can go on to bromate.
Because bromate is stable, the answer is prevention rather than detection. It is controlled before it forms, the discharge is held at or below 10 micrograms per litre measured at the outlet, and a failed batch leaves with us instead of going out of the pipe.
Do nanobubbles generate hydroxyl radicals?
The literature disagrees with itself. Moleaer and Arizona State University reported reactive oxygen species including hydroxyl radicals in 2020. A controlled 2023 study by Chae and colleagues in ACS ES&T Engineering found generation minimal at best under ambient conditions.
Neither result is priced into a Fluid Nano programme.
Has anything like this been tested by somebody independent?
At pond scale and tank scale, yes. NOAA's coastal science centres validated an ozone nanobubble aeration system on an eight-acre Florida freshwater pond in 2018, and separately assessed a nanobubble ozone ballast water system with no statistically significant adverse residual toxicity in the receiving water.
Neither names Fluid Nano or Alarivean. The 2020 one uses the initials NBOT for Nanobubble Ozone Technology, with a different institute as partner; this network uses the same initials for Nano Bubble Oxidation Technology.
Sources: NOAA NCCOS, 2018 · NOAA NCCOS, 2020
Does the asset have to come out of service?
No. The stage arrives alongside a running circuit, or floats on a body of water that stays in use. Nothing is drained, lined or isolated for our convenience.
If you already have an outage booked we will happily work inside it. We will not ask you to create one.
Two questions to open with
Ask about bromate. Then ask about the eleven.
On a saline duty bromate is prevented at source and the discharge is held at or below 10 micrograms per litre, measured at the outlet with no dilution credit. The eleven is the top of a reported range rather than a constant, and a stage is sized off the bottom of it. Send the water chemistry with your first message and both answers can be specific to your water.