Hydrocarbon contamination of sour water streams feeding sour water strippers is a well-known challenge in the refining and gas processing industry. The source of this challenge is the formation of a stable oil emulsion in an aqueous phase that may contain both H2S and NH3. The typical approach to the problem involves large residence time tanks under the estimation that droplet settling will occur over a long enough time frame. In practice, droplet settling is very slow due to a variety of reasons, and as a result, operators encounter sour water heat exchanger fouling, stripper fouling, hydrocarbon excursions to sulfur recovery units along with other operating challenges. This course will address the relevant issues and identify possible approaches to optimisation, with very significant contribution to energy savings, emission control and improved sulphur recovery goals.