Water treatment for cooling water

Use of water
in cooling circuits

In power stations, industry and commerce, waste heat has to be dissipated, i.e. a cooling circuit is required. The most commonly used coolant is water. The cooling circuit can be open, closed or be designed as a hybrid solution. Open cooling circuits are the most widespread.

In an open cooling circuit, chemically pure water is extracted from the circuit by evaporation and dissolved salts as well as other contaminants are left behind. This process is called cycles of concentration.

In order to run the cooling circuit at a target cycles of concentration, a portion of the cooling water is discarded at regular intervals (blowdown). These losses must be compensated for with treated make-up water.

Water treatment
for cooling systems

Suitable water treatment is indispensable when it comes to operating cooling systems with the highest possible cycles of concentration and thus low water consumption. In addition, the 42nd German Federal Immission Control Act (BImSchV) requires monitoring of the cooling water in order to prevent microbial contamination.

We offer all the required technology for cooling tower applications – from treating make-up water with softening units and reverse osmosis or nanofiltration for higher cycles of concentration to our specially developed dilution control system, Cooltrol data, which features an extensive range of functions and documentation of the operating data.

Water treatment plants Made in Germany

Nanofiltration Unit NF-S7 20000 AS/FU/SO
Cooling tower feed at an automotive manufacturer in Germany

Filtration Unit Oxidator / HEF + HSF / DEFU
Cooling tower water for a chemical industry in Bosnia and Herzegovina

Reverse Osmosis Unit UO-S7 18000 AS/FU/SO
Cooling tower water for a pharmaceutical industry in Germany

Reference project cooling water
Reverse osmosis system with PLC

Special system for the treatment of hardness-stabilised raw water. For innovative and clearer operation, the reverse osmosis system is equipped with a memory-programmable control system. In addition, this control technology enabled the implementation of a BUS connection for data transfer to the BMS (BACnet in this case).



German specialist for waste oil disposal and regeneration



Cooling water supply


System technology of the UO-S7 15000 AS FU

  • Reverse osmosis system with 15 m³/h capacity each
  • Raw water stabilisation through antiscalant dosing
  • Control system - S7-1200 incl. BACnet connection
  • High-pressure pump with integrated frequency converter

Energy saving

30% through FU pump


Product catalogue

Product overview 2024

Herco general catalogue 2024

File format:
PDF / 4.9 MB

Feel free to sign up for our newsletter
All our new products and the dates for free webinars at a glance

Info & Advice

Are you interested in our solutions?

Please select how we can help you. If you have any further questions, please contact us directly at any time.

Request a consultation

Non-binding on your desired date

Request a quote

Directly by e-mail

Please feel free to contact me directly

Ibrahim Davulcu
Account Manager for Industry

Antwort innerhalb 24 Stunden

+49 (0) 7141 7095 139
Mo-Fr 9:00 - 17:00


Request a consultation

Please let us know your topic and the desired date so that we can prepare your consultation in the best possible way.

How may we advise you?
What is the sum of 8 and 9?

Quotation for a water treatment plant

To prepare a quotation, please provide us with all the data and values you know about your project.

Your data

Your requirements

Is CIP cleaning necessary?*
Is hot water sanitisation of the system necessary?*

Which media are available?

Voltage and frequency

Compressed air

Is communication with a control system to be provided?
Contribution by HERCO?*

Untreated water values

Untreated water analysis available*

Enter untreated water values or upload here




Target water values

Do you know the values of your target water?**




Please add 1 and 5.

Contact form

Please let us know your request.

Please calculate 2 plus 7.


Please let us know your request.

What is the sum of 5 and 9?