Two-stage wet oxidation process for treating wastewater

摘要

A two-stage wet oxidation process for COD removal from high strength wastewater is disclosed in which the wastewater stream (10) is treated in a first stage subcritical wet oxidation zone (20) at temperatures between about 250o and 374oC to remove a substantial portion of the COD, and, subsequently, all or a portion of the first stage oxidized waste stream is treated in a second stage supercritical wet oxidation zone (28) at temperatures of 374o to about 600oC to remove any remaining COD content. Both stages of wet oxidation treatment are carried out at essentially the same system pressure.