Removing salt of the earth
8 Jan 2003
A supercritical oxidation unit developed by two Japanese firms could be used to destroy wastes and sludges from water treatment and contaminated land clean-up, the companies claim.
To be marketed under the name 'AquaFlame', the process uses supercritical water, but is said to avoid problems such as corrosion and plugging by salts which accumulate during the oxidation reaction.
The process, developed by Kurita Water Industries and Komatsu, centres around a preheated cylindrical reactor. Supercritical water is sprayed into the bottom of the tank, while waste fluid is pumped into the top and immediately heated to 650 degrees C, which decomposes any organic material. Salts deposited on the reactor walls are removed by a scraper and dissolved in water.
The resulting solution is discharged.
