Method and Apparatus for Water Purification using Continuous Hydrothermal Oxidation Regime

A system and method for cleaning dirty water is disclosed. The systems and methods may include two heat exchangers, including a high temperature/high pressure (HT/HP) heat exchanger that receives superheated steam and hydrogen gas and a low temperature/low pressure (LT/LP) that receives steam at a reduced temperature and pressure. The LT/LP heat exchanger provides first stage heating to dirty water that is input into the system for cleansing. The LT/LP heat exchanger has a first coil and a second coil. The first coil carries the dirty water to be cleaned. The HT/HP heat exchanger provides a second stage of heating to the dirty water that is output from the LT/LP heat exchanger. A first coil of the HT/HP heat exchanger carries the superheated steam and hydrogen gas. A second coil carries the preheated dirty water that is output from the LT/LP heat exchanger.