Technical note

Chemical-free cooling water treatment: how far can it go

No dosing under normal operation — but what about commissioning and water quality swings? Four conditions to check before you consider it.

The question every customer asks first

"Can your electrochemical system really run with no chemicals at all?"

There is no one-line answer — not because we are vague, but because it depends on which operating condition we are talking about. Being clear about the limits is more useful than a comfortable promise.

1. "Chemical-free" means normal operating conditions

Under normal operating conditions, JT-ECT does not dose scale or corrosion inhibitors, nor biocides. This is our stated scope, and it is written into the selection calculation as an applicable condition.

There are situations where temporary dosing still has to be decided on site:

• Commissioning (existing scale, rust and biofilm are disturbed);
• Large swings in make-up water quality (source switching, high turbidity after rain);
• Long low-load periods, or restarting after a shutdown.

We will not promise "no chemicals under any circumstances". Suppliers who put that sentence into a contract are usually transferring the risk to you.

2. Three things happen at once

• Descaling: the working cathode is a 316L plate stack; calcium and magnesium deposit on the cathode surface and are carried to the bottom of the reaction vessel for periodic blowdown. Scaling components are removed from the system, instead of being held in solution by an inhibitor. This is what allows higher cycles of concentration.
• Biofouling control: the anode generates active oxidizing species that suppress biofilm on fill and in the basin.
• Corrosion: the shell (Q245R) is connected only to cathode potential for corrosion protection and equipotential bonding — the shell does not carry current. The working cathode is a separate 316L plate stack.

3. Four conditions decide whether chemical-free is realistic

1. A side-stream is possible — the system can be tapped for a side-stream branch;
2. Make-up water quality is reasonably stable, with basic water testing on site;
3. You intend to run the equipment long term, not as a one-off cleaning job;
4. Circulating flow is between 200 and 2,000 m³/h (our JT-ECT-330 / 500 / 1000 range).

If any of these does not hold, we say so directly instead of taking the order first.

4. How to find out whether it fits your plant

You do not need to prepare a study. Send us two things:

• Cooling tower rated flow (the tower model number is enough);
• Make-up water analysis: calcium hardness, total alkalinity, chloride, TDS — whatever you have; we will confirm the rest by phone.

We recalculate from your water quality: mass balance, Faraday calculation, equipment selection — and issue a calculation report that states the applicable conditions and assumptions together with the results.