Membrane process to protect the Mediterranean: treatment of oily wastewater

摘要

Over the last decade, membrane filtration has appeared as a rentable and a powerful process to conventional unit method for purifying waste water. In particular, the high resistance to extreme conditions of ceramic membrane gives the opportunities to treat more and more complicate effluent. The aim of this paper is to develop an industrial process for separating oils from oily wastewater by membrane process. This study could assist naval and commercial vessels that generate large volumes of oily wastewater, mostly in the form of bilge water and ballast water. The separation is accomplished by the combination of a decantation step and an ultrafiltration step. The objective is to produce a treated water stream suitable to discharge in the sea and to reduce the volume of waste stream which must be subsequently treated either onboard ship or onshore. From the laboratory scale to industrial plant, we have studied the effect of operating conditions and the pretreatment. The scaling up is realized and the results obtained in two ferry are presented.