Study of Spent Caustic Wastewater Treatment Methods in Petrochemical Plants and Simulation of Optimum Process

Fresh caustic scrubbing is commonly applied in petrochemical and refinery plants for sweetening process. The wastewater produced is known spent caustic wastewater, Spent caustic contains noxious components such as sulfur compounds, phenol, mercaptans, and high COD. A various treatment methods exist. Treatment of spent caustic can be carried out by either biological or oxidation, each of which can be divided into subcategories. The chemical oxidation is divided into three way wet air oxidation (WAO), advanced oxidation (AOP) and catalytic oxidation (CAO) (Karimi et al, 2016; alniazy, 2008). In this work, the treatment methodology of spent caustic wastewater was investigated by applying the analytic hierarchy process (AHP) and finally is simulated optimal method via Aspen Hysys software.