The sour water generated from several process units is stripped of its H2S and NH3 content in a sour water stripper (SWS). The stripped H2S is sent to the Sulphur Recovery Unit. The stripped water can be reused in appropriate services (such as in the CDU Desalting unit) to reduce the amount of purchased fresh water needed in the refinery. Sour water from the stabilization tank is heated in a heat exchanger and fed to the top of the tower. Steam (or air) from below the tower rises to remove the dissolved gases. The steam is typically produced by a reboiler (rather than injection) so as to limit water consumption.