Centrifugal Flotation Technology Evaluation for Dissolved Organics Removal from Produced Water

Abstract

The aim of this chapter is to introduce an compact system for produced water treatment that is under development, the CFS (Centrifugal Flotation System) which combines the classic flotation and centrifugal separation processes. In the CFS, the bubbles generation, the flocculation and the droplet-bubble contact pass through a pneumatic flocculator, while the separation of the gas phase and the phase rich in oil is achieved using a cylindrical hydrocyclone. In the quest for new produced water treatment concepts, this chapter aims to evaluate the preliminary performance of a Centrifugal Flotation prototype with a feed flow rate of 10 m³/h, designed and built at Petrobras Research and Development Center (CENPES) to remove dispersed oil, sulphide and soluble compounds such as benzene and toluene, using hydrogen peroxide as oxidant. During the field tests, it was possible to achieve a sulphide removal above 95% and considerable removal values for benzene and toluene from the produced water using a hydrogen peroxide concentration of 100 ppm and a gas flow rate of 10 Nm³/h.