Application
of chlorine dioxide preparation systems in the sectors of drinking
water, bottle disinfection and power stations
In the sectors of drinking water, power station water treatment
or in the CIP plants of the food and beverages industry (e.g. bottle
cleaning) a disinfection agent has to meet the following demands:
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easy generation |
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safe
monitoring and control of the concentration |
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safe automatic
post-dosing |
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broad spectrum
of effectiveness (bacteria, yeasts, spores, viruses) |
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easy rinsing
out |
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low pollution |
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cost saving |
When used in waterworks or power stations,
the protection of the network of pipes is important. The disinfection
agent has to provide
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a long-term
stable disinfection effect |
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low corrosion
of metals |
Chlorine dioxide cannot be stored for chemical
and physical reasons. Therefore, it is necessary to generate it
on site (e.g. in the waterworks or power station). The Grundfos Alldos preparation
systems are working according to the hydrochloric acid/sodium chlorite
process (Oxiperm 166) or they generate the decontamination agent
using sodium chlorite and chlorine (Oxiperm 164).
The advantages of disinfection with chlorine dioxide are various: Especially for drinking water, which we
all are depending on, it is essential to use a chemical unrisky
for health:
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Chlorine
dioxide suppresses not only the forming of the volatile haloforms,
but also reduces the generation of hardly or non-volatile
organic halogen compounds considerably.
Primarily the volatile haloforms such as chloroform, but also
dichlorobromomethane, chlorodibromomethane and bromoforme,
are suspected of being harmful to health, some even carcinogenic. |
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Unlike
chlorine, chlorine dioxide does not form any chlorophenoles
affecting taste and smell. It reacts neither with ammonium
nor with amino compounds. |
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Low
concentrations of chlorine dioxide are applied as chlorine;
it disinfects faster and its effect is due to its permanency
in water also reliable in extensive networks of pipes. |
The disinfection effect of inorganic agents
such as chlorine dioxide depends on their redox potential. A high
redox potential is decisive for effective decontamination. Chlorine
dioxide is used for the oxidation treatment of water, for deodorising,
fighting of algae and mucus, reduction of CSB/BSB and AOX for reasons
of its high redox potential:
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The highly reactive
chlorine dioxide has an oxidation capacity of more than 100
to 250% compared with chlorine. |
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Destruction of chloramines by oxidation, no irritation of
eyes, no special smell, pleasant ambient climate (chloramines
lead to irritations of the mucous membranes, especially those
of the eyes). |
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No reaction
with ammonia or ammonium ions |
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Strong algicide
effect of chlorine dioxide: no necessity to use organic biocides. |
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The disinfecting
effect is not depending on the pH in the pH range from 6 to
10. |
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positive
effect on the skin by oxygen transfer (no degreasing, no smell
,...) |
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Destruction of dirt and microbacteria deposits e.g. at the
basin or in the pipes. |
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Chlorine dioxide
has outstanding bactericide and bacteriostatic characteristics. |
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The germicide
as well as the sporicide and the virucide effect of chlorine
dioxide is outstanding.. |
Economic advantages:
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Chlorine dioxide
is a very cheap disinfection agent |
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Thanks to the
destruction by oxidation of the bonded chlorine and the reduction
of the THM contents, less fresh water has to be added (usually
the back-rinsing per time unit is divided by two); the consumption
of water and energy is reduced at a considerable extent. |
Conclusion:
Chlorine dioxide is the alternative
for cost-saving disinfection. It can be integrated very well into
process systems technologically, as it can be automatically measured
and controlled. In the sectors of disinfection and in the water
and waste water fields very big savings are possible, simultaneously
increasing the operating safety and protection of the environment. |
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