4
2.
Introduction
5
NOTE:
During the regeneration process the systems allows
the passage of the non treated water in order to ensure
the disponibilty of the water to be consumed.
2.4 Regeneration grade and capacity
The exchange capacity is the quantity of hardness that a parti-
cular resin volume can keep before getting useless. This value
can be expressed like ºHFxm3/liter of resin.
The higher the resin volume is the higher hardness can be
kept by this resin before getting useless. This way it will be
able to treat a higher quantity of water before starting regene-
ration. It is important to choose the system that better suits the
concrete needs of each installation.
Depending on the quantity of sodium chloride used to rege-
nerate each liter of resin the capacity of exchange can differ.
Normally the denver systems are provided with a program-
mation with a regenerating grade of , 250grNaCl/resin liter and
an exchange capacity of 6,5ºHFxm3/resin liter.
2.5 Work volume
The softeners with ionic exchange should respect the suitable
contact times between the water to be treated and the resin in
order to ensure that the softening process is correctly carried
out. For DENVER systems you should respect following work
process:
Minimum volume (liters/hour): Resin volume x 4
Maximum volume (liters/hour): Resin volume x 40
In case of work volumes are out of the recommended ranges
this can affect the correct work of the system (too high charge
loss, harness leak…)
You can find more information about the minimum and maxi-
mum volumes for each type in the general characteristic board
2.6 Hardness leak
The ionic exchange process in which the softening water is
based can be affected by different parameters that can redu-
ce its efficacity creating a kind of hardness leak.
HIGHER SODIUM CONCENTRATION IN THE TREATED
WATER
The ionic exchange process in which the softening
water is based can be affected by different parameters that
can reduce its efficacity creating a kind of hardness leak.
EXCESSIVE VOLUME
It can affect the exchange process
REGENERATION GRADE
If there is no enough time, part of the hardness cannot be kept
by the resin
2.7 Residual hardness
Depending on the application of the treated water it is ne-
cessary to have it completely softened or on the contrary it
is better to have a certain amount of residual hardness. The
DENVER systems are designed to provide softened water and
even in this case the control valve has a residual mixing hard-
ness that allows to regulate the desired grade of hardness in
the treated water. (see Section 7)
NOTE:
For drinking water it is recommended a residual
hardness between 5 and 10ºHF when the tubes are of
copper and between 8 and 10ºHF when the tubes are
of iron (in this last case it is recommended to install af-
terwards a polyphosphat filter).
2.8 Sodium increase
The majority of the sodium that we are daily consuming co-
mes with the food and also with the preserved/canned food
because the salt is an excellent preservative and it is used like
and additive for the prepared products.
The ingestion of sodium with the drinking water is low compa-
red with the quantity that we are getting with the food.
However, it is important to bear in mind, as we have
said before, that the softeners equipments increase the so-
dium cocentration existing in the treated water (compared to
the concentration of the same at the initial moment of water
treatment).
