Production of Chlorine Dioxide with the SO2 - Reduction Process

The Process and Chemistry
Chlorine dioxide is produced by a chemical reaction, in which sodium chlorate, sulfuric acid and sulfur dioxide are the reactants. Spent acid is obtained as a by-product with the release of heat. The spent acid is a sulfuric acidic solution of sodium sulfate that, quite often, can be utilized. The heat, on the other hand, has to be dissipated to maintain optimal conditions.

The chemical reaction could be summarized as follows:
2 NaCIO3+H2SO4 +SO2  2 ClO2 + 2 NaHSO4 + heat

The chlorine dioxide gas obtained in this way is collected from the reactor and washed before being absorbed in water and stored as an aqueous solution.

Main Features
THE PROCESS
- chlorine-free ClO2
- capacity range available 1-25 MTPD ClO2
- chlorate yield - 88-90%
- easy to operate
- relatively low investment cost compared with other process alternatives
- low acidity in the chlorine dioxide water product
- spent acid can be used as sulfur and sodium make-up or for other acidification purposes
- no steam required for operation

THE EQUIPMENT
- well-proven technology as basis for design
- titanium in the reactors provide long service life and low maintenance costs
- carefully designed explosion hatches on reactors and towers provide a high degree of safety

For further information and technical details, contact a Eka Engineering Sales Representative.