Base Exchange Softeners

Base Exchange softening is a chemical process employed for permanently removing the hardness minerals that cause scale encrustation in hard water. Where appropriately sized and well maintained they will provide ongoing protection against scaling to downstream services and appliances.

Base Exchange softeners utilise an ‘ion exchange’ resin held within a tank to remove positively charged calcium and magnesium ions and replace them with negatively charged sodium ions. The now ‘softened’ water, containing higher levels of sodium, is no longer capable of precipitating hardness minerals into scale. Because of the increased levels of sodium the ‘softened’ water may not meet the requirements for safe potable water so separate untreated mains water supplies should be used to feed drinking water outlets.


All Base Exchange softeners will have a maximum amount of water the resin is capable of ‘softening’ before it requires regeneration. During regeneration the resin beads are flushed with a brine water solution, which is created by dissolving sodium chloride in a brine tank. The solution replaces the sodium that has been lost in the ion exchange process thus regenerating the resin. There will inevitably be some environmental impact from the flushing to waste of large amounts of water with concentrated levels of chlorides (this impact can be reduced somewhat by using more efficient softeners requiring less sodium).


simplex softener

Simplex Softener

Duplex Softener

Duplex Softener

During regeneration of the resin beads they cannot be used to soften any water, which means that periods of downtime to allow for regeneration will need to be factored in to the normal operation of a ‘Simplex’ softener – a softener with a single resin vessel. Where this isn’t practical a more expensive ‘Duplex’ softener can be used. The ‘Duplex’ system features two resin vessels, which alternate during regeneration to allow for constant usage.


Lifescience Products Ltd are experts in hard water treatment and offer a market leading range of Base Exchange softeners for all commercial and domestic applications. They also manufacture Water-King; the ‘fit and forget’ alternative to salt softening. Water-King is the only device of its kind proven by independent laboratory tests to partially soften hot water, requires no services or maintenance, complies with Part L Regulations and retains all of the healthy minerals found in hard water. To find out more click here.


Are you a consultant, installer or merchant looking for more information on Base Exchange softeners or in need a quotation? To get expert technical advice, please call our helpline on 01608 811707 or click here to send an email enquiry (be sure to mention if you need a simplex or duplex system and the maximum flow rate).