Electrochemical treatment of bilge wastewater

Abstract

Bilge water generated on sea ships is a mixture of water and hydrocarbons that must be further separated and treated. In this work, an innovative electrochemical reactor, with parallel plate electrodes, is operated to achieve separation and flotation of oily traces, electroreduction of contained metals and electro-oxidation of dissolved organic matter. All the environmental parameters measured in the study (i.e. colour, turbidity, COD and Pb–Zn concentration) were reduced by the process (average reduction for the 2-h experiences 80, 70, 50 and 40%, respectively). Increasing the imposed current favours all the processes occurring in the cell; however, there exists an optimum in terms of energy consumption for target organic load removal.

Keywords:

• Bilge wastewater
• Electro-oxidation
• Oily wastewater
• Electrochemical flotation
• Electrochemical remediation

Acknowledgements

The financial support from Fondecyt (Project No. 11070219) and the vice-rectory of research at the PUCV are gratefully acknowledged, along with the industrial support of Riltec S.A. (Valparaiso, Chile).