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:: Chlorine Dioxide Generator Comparisons ::
Chlorine dioxide generator are essentially chemical plants which reacts precursors to
produce in excess of 95 to 99% chlorine dioxide gas which is then
dissolved in water and delivered to the point of application. This is the
so-called ' in-situ' or on-site generation of chlorine dioxide. These
plants are set up by the manufacturer to convert as much of the
precursors to chlorine dioxide and to minimise the production of chlorate
as the by- product.
It must be pointed out that these generators are chemical plants that
need to meet the relevant safety requirements of the Factories Act, NOSA
etc.
These generators, if purchased from reputable manufacturers, will be
built with multiple safety devices and are generally stand alone units
which are automatically monitored and controlled using either in line
chlorine dioxide meter or a redox potential meter.
Methods Of Manufacture Of Chlorine Dioxide
There are a number of commercial methods that are currently in use for
the manufacture of Chlorine Dioxide and these are arranged into three
different categories. A brief evaluation of each with the pros and cons is given below.
1.1 Electrolysis
Electrolysis of salt (brine) solution under the correct operating
conditions is used to manufacture Chlorine Dioxide.
1.2 Sodium Chlorite
There are a number of methods using Sodium Chlorite as the feedstock that
are commercialised for the production of Chlorine Dioxide. We will review
each method, its chemistry, pros / cons and costs.
1.3 Sodium Chlorate
Sodium chlorate is the precursor of choice for the pulp and paper
industry where it is reacted with hydrochloric acid in gaseous form to
generate chlorine dioxide in titanium coated generators.
These systems
are large producing in excess of 50 000 tones per annum of chlorine
dioxide.
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