Water treatment at the world of wellness in Aachen, Germany

The Carolus Thermen in Aachen in Germany, named after king Charles the Great, are an unparalleled world of wellness. The demanding job of treating the thermal water is handled by our modern electrolysis system and the powerful measuring and control system.

Gaining the top spot

For years, the Carolus Thermen in Aachen have enjoyed the highest turnover and best financial returns of any bathing complex in Germany. With around 340,000 visitors a year, the thermal baths welcomed their 5 millionth visitor in September 2014. To keep numbers up in the future, the operator deploys specific renovation and optimization measures to always keep the baths fully state-of-the-art.

The thermal water used in the Carolus Thermen comes from the “Rosen” spring and the town supplies. Before the water enters the numerous baths in the bathing and sauna complex, for reasons of hygiene it has to be treated in line with the necessary requirements. Because of the mineral content of the thermal water, in the past large amounts of acidic products had to be used to correct the pH. New water treatment system technology and efficient measuring and control technology should improve this.

Key data

  • The baths and saunas attract around 340,000 visitors a year
  • Installation of water treatment system technology and new measuring and control technology while the baths remained open to the public
  • Electrolysis system CHLORINSITU® V Plus disinfects the natural thermal water and water from the town supplies
  • Measuring and control system DULCOMARIN® II controls hygiene parameters in 15 water circuits

Investment in leading technology

The operator chose two competent partners for the job: m. hübers GmbH from Wesel handled the installation and ProMinent GmbH supplied the technical components and systems. Firstly, in April 2016 the measuring and control technology was fitted with the powerful DULCOMARIN® II and 15 locally distributed measuring points to control the auxiliary hygiene parameters and the new products were started up. The second stage in July involved the installation and commissioning of the electrolysis system CHLORINSITU® V Plus with a chlorine production rate of 1750 g/h. In addition to these build stages, nine flow monitors were installed to shut down the supply of chlorine should the water requiring it stop flowing. Finally in December 15 solenoid driven metering pumps of type Beta® were fitted for automatic pH control.

The savings are fantastic

The chlorine gas produced locally by the CHLORINSITU® V Plus is supplied directly to the thermal water within the electrolysis system. The hypochlorous acid produced in the process itself reduces the pH, meaning that far fewer acidic products have to be added. Considerably fewer additives are also needed to control the pH in the pools filled with water from the town supplies. The sodium hypochlorite also produced in the CHLORINSITU® V Plus and held in a storage tank is the ideal solution for disinfecting water. The storage tank also serves as an “emergency reserve” for the thermal baths should an unforeseeable fault occur in the chlorine production system. A totally safe solution!

  • Perfectly hygienic pool water at all times in all thermal baths and the sauna area
  • Linking DULCOMARIN® II to the company’s own network means that hygiene parameter can be accessed on the pool caretaker’s PC at all times and rapid intervention is possible
  • Significant savings in chemical consumption cuts operating costs
  • Storing sodium hypochlorite ensures fail-safe operation for at least 24 hours
  • Defined contact for service work and reliable supply of spare parts

»We didn't want an off-the-shelf product but a solution tailored to the specific requirements of the Carolus Thermen. We are delighted with how smoothly the project ran and the new technology was installed while the facilities were still up and running. Alongside the sizeable reduction in costs, continuous service and the rapid supply of spare parts are huge benefits.« -  Michael Blinn, technical manager Carolus Thermen Bad Aachen

Used Products - Water treatment at the world of wellness in Aachen, Germany

  • Electrolysis systems of type CHLORINSITU V Plus generate ultra-pure chlorine gas directly on site and only need salt, water and electricity to do so. Peaks in demand can be covered by this system (Plus system). They are especially well suited to systems for disinfecting potable water, wastewater, process water and water in swimming pools and cooling towers.


Contact us

Wesley Sutton

Managing Director, ProMinent Fluid Controls UK Ltd.

»We are always available to help. Don't hesitate to contact us.«

+44 1530 560 555  Send request   

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