SUPERCRITICAL WATER OXIDATION WITH REDUCED CORROSION AND ENHANCED OXIDATION RATE

摘要

A process and apparatus for the oxidation of hetero-atom (Cl, N, S, P, F, etc.) containing material in supercritical water that avoids corrosion and increases oxidation rate is disclosed. The process uses basic inorganic salts (e.g., sodium carbonate or calcium carbonate) that are insoluble in supercritical water. The process employs supercritical anti-solvent method to form fine particles of these basic salts in the reaction zone to provide high surface area for both catalysis of the oxidation and neutralization of the corrosive acidic species. An apparatus to accomplish this process is described which consists of two preheated inlet streams for the material and oxidant, and one non-preheated inlet nozzle for spraying the inorganic salt solution in the supercritical reactor. Most of the corrosive species collect on the particle surfaces. Upon cooling, the particles dissolve back in water, avoiding clogging in the downstream valves and pressure regulators.