Previous Article Next article Return to overview
Water treatment for the most discerning clientele:<br/>Aqua Zone at the Dolder Grand, Zurich

Water treatment for the most discerning clientele:
Aqua Zone at the Dolder Grand, Zurich

The Dolder Grand is one of Switzerland’s most outstanding spa hotels. The original Curhaus, or health spa, built in 1899, has been transformed into a luxury-class city resort. The hotel boasts an exclusive ambience of opulence and relaxation, with 173 luxurious rooms and suites, exquisite cuisine, large banquet and seminar rooms and a new 4000 sqm spa. Running a hotel of this standard requires superior technology – an important part of which was supplied by ProMinent.


The system includes:

  • ProMinent measuring and control technology with multi-channel measuring and control system Dulcomarin® II DULCO-Net for a maximum of 16 filtration circuits with Local Area Network (LAN) and embedded web server.
  • 1 panel-mounted measuring station equipped with measuring and control unit Dulcomarin® II and DULCOTEST® sensors to measure pH / redox / free chlorine / temperature
  • 9 panel-mounted measuring stations equipped with measuring and control unit Dulcomarin® II and sensors in flow gauge housings to measure chlorine and temperature

The Dolder Grand Spa is shaped by the organic concept used in the pool area. The Aqua Zone includes indoor and outdoor whirlpools, a sanarium, a steam bath, and a snow paradise to cool off in. Guests can experience the relaxation of a Japanese sunaburo as they relax in a bath of warm pebbles. The large swimming pool offers a vista of the hotel’s natural surroundings. Other facilities in the separate spa areas for men and women include saunas, steam baths, kotatsu foot baths, aroma pools, steam pots, cold-water pools, and stand-up solarium. There are also workout, movement and mind/body studios.

This is a hotel that sets very high standards – and this applies equally to the water treatment technology. The water is expertly chlorinated and neutralised by a system of pumps and convenient measuring and control units. The water for the swimming pool, whirlpools and aroma pools is efficiently treated in multiple stages using seven separate circuits.

All circuits are supplied with a liquid flocculent by a Beta® type ProMinent solenoid diaphragm metering pump.

A constant neutral pH is achieved by ProMinent Beta® type solenoid diaphragm metering pumps, which automatically add hydrochloric acid to the water. The control signals are sent to the pumps by the central unit via LAN.

9 plattenmontierte Messstellen ausgestattet mit Mess- und Regelgerät Dulcomarin® II sowie entsprechenden Sensoren in Durchlaufarmaturen für die Messgrössen Chlor und TemperaturChlorination
Chlorine is added by 14 LAN-controlled solenoid diaphragm metering pumps with a CANopen interface, which serve as a reservoir for all circuits and the backwash and cold-water pools.

Because the amount of chlorine added depends on the condition of the water, the system only adds as much chlorine as is absolutely necessary. The pumps are controlled by multi-channel measuring and control systems from the Dulcomarin® II series.

Measuring, monitoring and control
The superordinate control unit is the ProMinent multi-channel measuring and control system Dulcomarin® II DULCO®-Net. This is the first bus system to provide effective networking for swimming pool facilities. The pH, total chlorine, free chlorine, temperature and redox potential of the water are measured by a panel-mounted measuring and control system Dulcomarin® II central unit and selective DULCOTEST® sensors.

Water treatment technology from ProMinent ensures that the water in the spa facilities at City Resort Dolder Grand satisfies the very highest standards. The water in the Aqua Zone is neutralised and disinfected safely and reliably in a monitored process. Guests can relax and indulge knowing that the water is exceptionally hygienic. The hotel has reduced its costs in two ways: firstly through the minimised use of chemicals and secondly through the automated water treatment process, achieved by integrating the measuring, control and metering technology into the process control system.

Print this page