The sodium chlorite production is composed by three unit operations: the electrolytic sodium chlorate production, the chlorine dioxide production and the sodium chlorite production through adsorbtion of the Chlorine Dioxyde in caustic soda and oxygen peroxide solution.
The adoped oxigen peroxide solution is a diluted solution and, for this reason, this process is safer than the conventional ones, which use the concentrated oxygen peroxide at 70 % V/V.
The liquor that is produced in the electrolyser is sent to a three phases chlorate separator, where a a solution of sodium bicromate is fed. The aim of this addition is improving the efficiency of the chlorate production.
In the separator, the brine that is recirculated to the electrolyser and the chlorate liquor are blown down at different levels, whereas the hydrogen is vented from the top of the separator.
The chlorate solution, after undergoing a few stages of filtration and cooling, is fed to the chlorine dioxyde generator, which is a fully manufactured in titanium reactor that it equipped with several safety systems, which are able to prevent the explosive decomposition of chlorine dioxyde.
The plant is also equipped with a multi points analyser, which is able to prevent the dangerous concentration of oxygen.
