(69c) Converting Refinery Spent Caustic to a Biodegradable Wastewater Stream

Refineries generate spent caustic in the MEROX, Kerosene, or jet fuel units. This spent caustic is hard to treat in biological processes due to the presence of sulfides and high toxic organics. Usually, refineries would dispose this waste off site for treatment or deep well injection. This could be costly depending on the geographical location of the site and the flowrate of the spent caustic generated. This paper will discuss how this stream can be treated onsite using wet air oxidation and/or electro oxidation units. The treated stream will be completely biodegradable and can be disposed to the plant WWTP.