Chemical-Free Water Treatment (SBR™) is a fully automatic online water treatment system that continuously cleans cooling tower water without a single chemical dose. Scale precipitates out in a reaction chamber instead of depositing on your heat exchangers.
The same cooling tower, treated two different ways — chemical dosing still leaves scale and biofouling behind; SBR™ doesn't.
Instead of dosing chemicals to keep hardness minerals in solution, SBR™ continuously draws a side-stream of cooling tower water through a reaction chamber where scale-forming minerals are precipitated out and removed. The treated water returns to the tower with dramatically reduced scaling and biological fouling potential — with no moving parts and no chemical storage or handling on site.
Treat cooling tower water without any chemicals.
Reduce bleed-off quantity from your cooling tower.
Increase cycles of concentration by 2–3x.
Reduce sewage treatment plant costs downstream.
Adopt environment-friendly water treatment.
By running at higher cycles of concentration and cutting blowdown volume, SBR™ reduces freshwater intake, effluent (STP) treatment costs, energy use, and the labour that used to go into managing a chemical dosing program. All precipitation of salts occurs in the reaction chamber — leaving no scale in your system's heat exchangers, and giving you control over corrosion potential thanks to the low aggression of treated water.
Save up to 60% on operational costs, with 100% chemical savings and 5–15% lower energy costs.
30–100% decrease in water usage, 10–50% lower labour costs, and up to $10/m³ reduction in STP cost.
Water reuse for irrigation, 2–3x cycles of concentration, and scale/biological/corrosion control — precipitation happens in the reaction chamber, so no scale reaches your heat exchangers, and treated water's low aggression keeps corrosion in check.
No chemical dosing, storage, or handling anywhere in the system.
Higher cycles of concentration mean less makeup water and bleed-off.
Typical payback on an SBR™ install is under two years.
No chemical discharge, no compliance burden, no handling risk.
SBR™ is installed across commercial buildings, industrial cooling towers, and power plants — and is especially valued during prolonged shutdowns, when chemical dosing programs are hardest to maintain and Legionella risk is highest.
| Criterion | Chemical | Chemical-Free (SBR) | Ozone | UV |
|---|---|---|---|---|
| Capital cost | Low | Medium | High | Low |
| Operating cost | High Chemical purchase, disposal | Medium-low | High Energy + maintenance | Low |
| Chemical-free | No | Yes | Yes | Yes |
| Legionella control | Conditional Depends on dose discipline | Full | Full | Partial No residual protection |
| Scale control | Yes | Yes | Partial | No |
| Residual disinfection | Yes | Yes | No Ozone degrades rapidly | No |
| Biofilm removal | Partial | Good | Excellent | No |
| ESG compatible | Limited | Yes | Yes | Yes |
| Standalone capable | Yes | Yes | Yes | No Supplement only |
| Operator dependency | High | Low | Medium | Low |
| Best system size | Any | Medium → large | Large + expert ops | Any (supplement) |
Biocides (chlorine, bromine, isothiazolones), scale inhibitors, and corrosion inhibitors are dosed into the cooling water at regular intervals via automated pumps. Chemistry is adjusted based on regular water sampling and analysis conducted by the treatment supplier.
Best for: Small to medium systems where capital cost is the overriding constraint; legacy installations where system change is impractical; applications with highly variable water chemistry requiring flexible dosing.
An electrical current passes through the cooling water via a side-stream bypass reactor, electrochemically generating hypochlorite biocide directly from the dissolved salts already present in the water. No external chemicals are purchased, stored, or handled. The system operates continuously and automatically — biocide is generated on-demand and delivers residual protection throughout the cooling circuit.
Best for: Medium to large cooling tower installations with significant existing chemical spend; ESG-focused operators; pharmaceutical, hospitality, data centre, and industrial operators subject to Legionella compliance obligations.
Ozone (O₃) is generated on-site by an electrical discharge generator and injected into the cooling water. A powerful oxidiser, ozone destroys bacteria, breaks down biofilm, and controls scale — then rapidly decomposes back to oxygen, leaving no chemical residue in the system or in blowdown discharge.
Best for: Large, sophisticated installations where total chemical elimination is a compliance or brand requirement; food and beverage processing; pharmaceutical and life sciences operators with strong in-house engineering capability.
Water passes through a chamber exposed to UV-C light (typically 254 nm), which destroys microorganism DNA — preventing reproduction — without adding any chemicals. Only water actively flowing through the UV chamber is treated; no residual disinfection is carried through the rest of the system.
Best for: Supplementary use alongside chemical or electrolytic treatment to reduce total biocide requirement; potable water polishing; low-risk, small-scale cooling systems.
Our SBR system is not the right answer for every application. Below are six situations where we would recommend a different technology — or tell you honestly that the business case for our system does not work for your site. We would rather lose a sale than install a system that underperforms.
Both produce hypochlorite as the active biocide, but conventional chlorination adds chemical chlorine from an external supply — purchased, stored on-site, and handled by operators. Electrolysis generates hypochlorite in-situ from dissolved chloride ions naturally present in the cooling water. No external chemical is purchased, stored, or handled at any point. The biocide is chemically identical; the supply chain, safety profile, and cost structure are entirely different.
No. UV disinfects water actively passing through the UV chamber but provides no residual protection anywhere else in the system. Pipework, storage tanks, dead-legs, and biofilm on internal surfaces remain entirely untreated. Most national Legionella risk assessment frameworks — including HSE ACoP L8 (UK) and ASHRAE 188 (US) — do not accept UV as a standalone cooling tower control measure.
The key decision factors are capital budget, engineering capability, system size, and blowdown discharge requirements. Electrolysis is the more practical choice for the majority of medium-to-large industrial and commercial operators — lower capital cost, no gas containment, and lower operator training demands. Ozone produces superior biofilm elimination and leaves zero chemical residue in blowdown, but carries significantly higher capital cost, energy consumption, and training requirements. For sites where chlorine in blowdown is a regulatory constraint, we will conduct a genuine comparative assessment before recommending our own system.
Yes. For small systems, legacy installations, or applications where capital cost is the overriding constraint, conventional chemical treatment remains a practical and well-understood solution. The case for electrolysis or ozone strengthens as system size increases, as chemical handling costs rise, and as ESG, Legionella compliance, and green building certification requirements intensify.
Three things. First, our system addresses microbiological risk, scale, and corrosion in a single integrated solution — many alternatives address only one of these. Second, we offer zero-downtime installation on live systems, meaning changeover from chemical to chemical-free treatment requires no planned shutdown. Third, every system is sized and configured on a site-by-site basis, with a typical payback under two years.
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