Measurement of
pH and applications
of ORP Meter can
be found in
diverse processes like disinfection, wine making, electroplating, and mining. Some
of the important
applications employing ORP Meter includes:
Disinfection of
municipal waste water
is often accomplished
through the addition
of chlorine. Chlorine is
generated through sodium
hypochlorite, calcium
hypochlorite or chlorine
gas in elemental
form. Chlorine then reacts with
water to form
hypochlorous acid. In
water treatment applications, an ORP
meter is used
to measure the
oxidation by controlling
the amount of
free chlorine, such that
a known bacteria
killing ORP level is
achieved. In similar manner,
ORP and hypochlorous
acid is used
to maintain pool
chlorination.
The amount
of dissolved oxygen
is an important
measurement parameter in
many processes. In power
plants, bioprocessing, and aquatic applications, it is
usually measured using
a dissolved oxygen (DO)
analyzer. In water treatment
applications, an ORP Meter is
used in conjunction
with DO analyzer
for biological nitrogen
and phosphate removal
using bacteria. Measuring the
ORP level using
the ORP
Meter helps to
monitor the bacteria’s
metabolic activity. This
helps to optimize
the removal process
in different environments (aerobic, anaerobic, and anoxic).
An ORP
meter is also
used to maintain
ORP level in
winemaking fermentation to
control aeration during
yeast fermentation.
Maintaining the correct
level of ORP
is crucial so
as to maintain
an aerobic environment
to inhibit the
formation of undesirable
aromas of hydrogen
sulfide and volatile
sulfur in the
final product.
In industrial
waste water treatment, for either
the reduction or
oxidation of components
before discharge, redox reactions
are used. For example, cyanide waste
water treatment. Cyanide is a carcinogen
and has to
be removed from
the water before
release. In the treatment
process, the redox reaction
is used to
remove cyanide completely
from water. This is
monitored using an ORP Meter that measures
the ORP level. A
plateau in ORP
level indicates complete
oxidation of components
and transition to next stage
of treatment.