Application of Ozone in Water treatment for Swimming pools
Anybody entering a swimming pool contaminates the water either from
secretion or just from washing off. Typical contaminated are
● Sweat
● Skin flaks
● Mucous
● Hair ointments
● Urine
In addition there are contaminants and organisms from the
environment of the swimming pools such as dust algae and
microorganisms therefore the pool water has to be constantly
filtered and disinfected.
At the present time only chlorine disinfection is used which means
use if chlorine, hypochloride and chlorine dioxide.
However, the disinfection efficiency of chlorine is very much
hindered by water contaminants.
For Example : In highly contaminated water even at a concentration
of 3.5mg/l of free chlorine, virus bacteria were found while
normally a tenth of this amount that is 0.3mg Cl 2/ltrs would be
sufficient to destroy the bacteria.
There are several causes for a reduction of Chlorine activity.
● Colloids may envelope bacteria forming a protective coat against
chlorine.
● Organic are oxidised by chlorine which reduces the concentration of
free chlorine.
● Ammonia and other nitrogenous compounds react with Chlorine forming
Chlorine-Nitrogen compounds which have slower in activation for
virus and bacteria.
These Chlorine compounds known as Chloamines and Chlorourea not only
produce that typical unwanted swimming pool odor. But are also
highly Irritant poisonous substances that cause Eye Irritation (
Redness of Eyes ) and Skin Allergy. Some of these chlorine compound
are found to be highly carciogenic.
The comfort of the swimmer keep a priority aspect is selection of a
swimming pool purification process.
Ozone is proved to be the most
Advanced & beneficial treatment processes .
Advantage of using Ozone v/s Chlorine
Ozone possesses many advantages over chlorine in the processing of
swimming pool water or in conjuction with chlorine.
Basically, ozone is used as a purification agent and chlorine is
used for disinfection. Actually, ozone can be used both as a
flocculating agent as a disinfectant in addition to its function as
a purification agent. The pool water is flocculated to remove
various colloidal material and substances that create turbidity, as
well as bacteria and virus. The water passes through sand filters to
remove the precipitate before being ozonated. By removing the
colloidal matter and the cause of turbidity, the ozone is given a
better chance of doing a fine job.
Some of the advantages and disadvantages of ozone and chlorine used
for swimming pool water purification are :
● Chlorine is not only highly toxic,
it is a poisonous gas
● Although ozone is rated as toxic
at the 1.0 mg/1 level by the United States government, no one has
ever been known to have died as a result of inhaling it. Ozone has a
very pungent odor, noticeable at the 0.01mg/1 level; is highly
irritating at elevated levels; tends to dry out the skin and mucous
membrane and can cause temporary throat discomfort.
● Chlorine is stored in high
pressure containers on the premises and can be dangerous. A broken
chlorine line could cause serious problems.
● Ozone is generated on the premises
(not stored)
● Chlorine, when mixed with urine and
perspiration, will form chloramines that will cause eye irritation
and are toxic to aquatic life.
● The cost of chlorine is constantly
increasing and has become quite expensive. Ozone, on the contrary,
is becoming less expensive due to the increase in efficiency and
lower energy consumption. The overall cost of using ozone instead of
chlorine will be less costly to the pool owner.
● Ozone is the most active oxidizing
agent that can be used with safety. It is sometimes called
“activated oxygen”.
● Tests have proven that ozone is
from 600 to 3000 times more active in the destruction of bacteria
and viruses than chlorine in the same concentration. Escherichia
Coliform (E. coli) is killed within 5 seconds by ozone at a
concentration of 1 mg/1, whereas 15,000 seconds for the same results
using chlorine at the same concentration.
● Ozone is effective against
mustiness, mildew, fungus and can be used to eliminate the “locker
room” odor in dressing rooms.
● Due to the flocculation process
and the ozonation process, the water in an ozonated pool is very
clear. A sky blue color is imparted in the pool water.
● Chlorine is more effective against
algae growth. Outdoor pools using ozone have a problem with algae
bloom, under high temperature conditions, that can be eliminated bu
chlorine “ shock treatment’ of 5 to 10 mg /1, when needed.
● Chlorine needs pH control (7.0 to
7.4 pH) for reliable results. Ozone does not not require pH control
but some of the other chemicals used may require such control.
● Ozone is an excellent deodorizing
agent for many substances, such as putrefactions, hydrogen sulfide,
urine, smoke, cooking, paints, etc.
● Ozonated pools do not have the
“bath tub ring” that is caused by skin oils, grease, ointments, hair
dressing and cosmetics used by the swimmers
● Ozone is used in therapeutic pools
and baths for the treatment of skin infection and burns.
unity for you to be self sufficient in the most essential commodity: WATER.
Cooling Water Treatment with Ozone
Ozone treatment of a cooling tower can
reduce the quantity of blowdown. Actual reductions will be system
specific, but can range from 50% to 90%. Although actual elimination
of blowdown altogether is unlikely, this is a very effective
technique used to reduce water consumption. Ozone decomposes into
oxygen, and therefore imparts no undesirable chemical residue into
the system. Therefore, blowdown from cooling towers treated with
ozone only will be free of biocide, scale, or corrosion control
chemicals.
Ozone is an unstable gas that will occur naturally during a
thunderstorm. There are also several man made sources such as
electronic copying/printing equipment, electric motors. For
industrial use, it is generated and it is to be used. The inherent
instability of ozone makes it impractical to package for use and
shipment.
Ozone can be generated from dry air, with a dew point of -51 o C or
less, or dry oxygen with a dew point of -51 o C or less. An air-fed
ozone generation system includes an air filter, air cooler,
compressor and dryer. Ozone reactions in cooling water are as
follows:
●
Biofouling Control
Ozone will disinfect more rapidly than any other commercially
available oxidant. This feature makes ozone a viable technique for
biofilm control and to attack organic binders holding scaling
materials to cooling water surfaces. The mucilage is usually
generated by bacteria in the system.
●
Organics
Ozone will destroy many organics commonly encountered in
recirculated cooling systems, some rapidly, some slowly, and some no
reaction. Ozonation of some organics will result in by-products that
will be difficult to oxidize further. Thus, although ozone is
effective in destroying many organics, all organics will not be
completely converted to carbon biocide and water.
●
Algae
Algae are readily oxidized by ozone. However, algae will reappear on
exposure to sunlight unless small ozone residual is left in the
system. Ozone levels in the 0.01 to 0.05-mg/l ranges, maintained for
a few minutes, are usually sufficient for algae control.
●
Corrosion Control
Current data on corrosion control benefits that are obtained by
using ozone is conflicting. In some cases, corrosion rates are slow
and others, more rapid. Mild steel and aluminum corrode slower with
ozone presence, whereas galvanized steel has an increased corrosion
rate versus water containing oxygen. It seems reasonable that some
corrosion is expected, but can be minimized by maintaining water
cleanliness.
It makes pool water very safe for swimmers & especially children. Research shows
that 