Veolia Water Technologies Deutschland GmbH

Gerold-Janssen-Straße 2
28359 Bremen, Germany
Phone: +49 421 53705 - 0
Fax: +49 421 53705 - 440

Process Water Treatment

Softeners and Ion Exchangers

Ion-Exchange Softening

The water softening is accomplished by ion exchangers, where the hardness compounds calcium and magnesium are removed and replaced with sodium. If water containing calcium and magnesium is passed trough an ion exchanger, these ions are taken up by the resin, which simultaneously gives up sodium in exchange.

After the ability of the bed has been exhausted to produce soft water the unit is removed from service and regenerated with a solution of sodium chloride. This removes the calcium and magnesium in the form of their soluble chlorides and at the same time restores the resin to its original sodium condition.

All RWO softening plants are characterised by a chemical and water saving regeneration mode, meaning that you will produce more softened water with less salt and less waste water.
This is saving money and salt storage space on board.

RWO ion-exchange softeners are of the pressure type, with either manual or automatic control. Small water softeners normally consist of a glassfibre reinforced plastic (GRP) vessels; the larger units are of steel construction with adequate corrosion protection.

As a standard the systems are designed for fully automatic operation, controlled by either simple and easy to operate electromechanical control units or else by latest state of the art microprocessor or PLC units.

A variety of accessories is available, e.g. sensor control for a quality dependent regeneration triggering, hardness-monitors for continuos hardness measuring and control, and optional upgradings for seawater regeneration to save further chemical and water costs.

Water Softening


Hardness in water is caused by the ions of calcium and magnesium.

The hardness of the water is of prime concern for many technical applications because of its scale-forming tendencies.
For this reason, some water users on board ship need softened water, e.g. hot water circuits, laundry water, boiler feed water, cooling water,...

And some need even more, i.e. a higher degree of demineralisation, than evaporators, reverse osmosis or softeners may provide. This is than achieved by an Ion Exchanger plant.

For both, softener and demineralisation units, RWO got the right solution:

  • Skid mounted units in a compact, marine suitable design
  • Chemical saving processes
  • Reliable and operations safe equipment
  • Electronically controls for automatic," hands-off " operation
  • All for a very competitive price

Water Demineralisation

A demineralisation plant is also an ion exchanger system, but goes one step further than the softeners by removing basically all dissolved ions from the water. The result is a fully demineralised water, low in conductivity and free of other impurities such as silica and CO2 - therefore suitable e.g. for ship turbines and other technical applications that require "pure water ".

RWO offers a variety of ion exchanger systems, co-current Cation-Anion plants, chemical saving counter current systems and mixed-bed units to suit all your specific needs.

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