498 / 836
Ozone
Ozoneisaverystrongoxidizingagentthatdestroysorganiccompounds
that are especially difficult to oxidize. It allows the pool manager to very
efficiently remove combined chlorine without frequently refreshing
large amounts of pool water. By the time the water passes through
the filter units, ozone has already completed sanitizing, and it is not
effected by the pH level.
Mainly because of its strong oxidizing power, the return water may
contain trace concentrations of ozone. It imperative to know that
ozone is very unstable, so to ensure thorough sanitization of the
water, low-level chlorination remains necessary.
The Water Balance and Langelier Index
Pool water characteristics need to be maintained in a balanced state
to avoid numerous issues. Measuring certain variables is extremely
important to predict if the water is corrosive or will cause scaling.
A saturation index developed by Dr. Wilfred Langelier is widely used
to predict the balance of swimming pool waters. It represents the
estimation of a solutions ability to dissolve or precipitate calcium
carbonate deposits. A certain level of this precipitation (filming) is
desired to insulate pipes and boilers from contact with water. When no
protective filming is formed, water is considered to be corrosive. On the
other hand, too much filming can develop into scaling and incrustation
of the pipes.
In the treatment and monitoring of pool water, the pool manager
must ensure that related parameters such as alkalinity, hardness
and pH are carefully monitored in addition to sanitizing chemicals.
Calcium
The presence of calcium in the system is desired to ensure filming on
those places where the temperature is relatively high, like in boilers
and pipes transporting warm water. Scaling must be avoided because
it reduces heat transfer and pump capacity, and causes cloudiness in
the water.
It is recommended to maintain the calcium hardness value within the
range from 200 to 400 ppm as calcium carbonate (CaCO₃).
Alkalinity
Alkalinity is the measure of the total concentration of alkaline
substances, mostly bicarbonates, dissolved in the water. The higher
the alkalinity, themore resistant thewater is to pH change. At the same
time, high alkaline water is a major contributor to scaling problems like
incrustation in filtration equipment, pumps, and piping.
It is recommended to maintain the alkalinity value within the range
from 80 to 125 ppm as calcium carbonate (CaCO₃).
pH
The pH of the water is an important factor since at lower pH levels the
corrosion rate increases. If the alkalinity values are sufficiently high,
it will not be difficult to control the pH. Most pool managers prefer to
keep the pH between 7.2 and 7.4 to best maintain low corrosion rates
and a sufficient activity of chlorine.
10
Photometers
10.34
|
www.hannainst.combenchtop