Apparatus and method for oxidising undigested wastewater sludges

摘要

An apparatus (90) for depressurizing a high pressure fluid containing solids in a supercritical water oxidation treatment system comprising: (a) A pressure reducing device (92) for receiving high pressure solids laden fluid and reducing the pressure of the solids laden fluid to a gas phase pressure at which a significant gas phase exists with a solids laden liquid phase. (b) A vessel (94) connected to receive the solids laden liquid phase and gas at the gas pressure phase. (c) A pressure regulator valve (96) associated with the vessel for maintaining the gas phase pressure in the vessel and allowing gas to exit the vessel to maintain the gas phase pressure. (d) A liquid removal conduit connected below a liquid level in the vessel and having a two-position liquid removal valve (98). (e) Control means (100) for moving the liquid removal valve (98) to a fully open position in response to an upper liquid volume value in the vessel and for moving the liquid removal valve (98) to a fully closed position in response to a lower liquid volume value in the vessel.