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Methods used to Soften Water.
Apart from boiling, hardness can be
removed
from water by using
washing soda
or an ion exchange column
in a water softener.
What is Washing Soda?
Washing
soda is sodium carbonate.
Adding sodium carbonate to hard
water
will precipitate insoluble calcium carbonate
or insoluble magnesium carbonate.
This is a way of removing permanent hardness
from water.
What is an Ion exchange
column?
A water
softener uses an ion
exchange column.
An ion exchange
column is a glass tube filled
with a resin
containing sodium ions.
Calcium (or magnesium) ions
in the water become exchanged
for sodium ions
as the water flows through the
column.
Eventually, the column becomes saturated in calcium
ions
and stops being
effective.
The column can be regenerated
by pouring sodium
chloride solution (salt
water) through it.
The calcium ions are flushed out and replaced with sodium
ions,
allowing the column to be reused.
For more information about how a
water softener works
please click here. A
water softener is different from a
scale inhibitor.
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