4TH International Congress on Technology - Engineering & SCIENCE - Kuala Lumpur - Malaysia (2017-08-05)

Biological Oil Removal From Seawater By Flexible Nano Ceramic Membrane
The constant increase of international trade and global economic interdependence leads to the rapid increase of vessel traffic on the ocean and at ports. These resulted in significant pollution problem at the port, which includes oil released from cargo tank washing and ship maintenance/cleaning or oil leakage. Traditional solutions for oil clean-up at the port or on the sea due to the oil spill are either physical, chemical methods or bioremediation. However, most of them are either not effective or costly, or not environmentally friendly. In this study, a biological oil removal method from seawater using flexible nano ceramic membrane was investigated. A lab scale system was setup using the total of about one meter square of flexible nano ceramic membrane TM as the support for the biofilm growth (Fig 1). Seven pieces of 250 mm (width) x 280 mm (length) membranes were folded and hang on metal bars. Membrane bioreactor has a dimension of 300 x 300 x 300 mm while the water volume being treated in the recirculation tank was about 15 L. Seawater containing oil was sprayed down to the membrane and flowed into recirculation tank below. The source of seeding bacteria is mud collected from a beach near a busy port area. The system was started up with vegetable cooking oil and sugar with necessary nutrient at a COD of 600 mg/L and oil content of 200 mg/L. COD concentration was then gradually increased to 3,000 mg/L and oil content to 1,000 mg/L in about two week time as the biofilm was building up. Vegetable oil was replaced with marine diesel oil after the biofilm was successfully formed onto the ceramic membrane. The content of marine diesel oil was analysed daily, and then it was changed to marine fuel oil (MFO) after the removal efficiency became stable. Various types of MFO including FO 180CST, FO 380CST and FO 500CST were tested in the study. The results showed that biofilm could be successfully formed in 2 weeks, and up to 90% of marine fuel oil could be removed in one day in the system. The study demonstrated an innovative way for the biological removal of oil from seawater and the end products of oil is carbon dioxide which has no secondary contamination to seawater like some of other current oil removal methods do. Based on the lab scale system result, a pilot scale system is being setup now to further test it in seawater at one of the sea ports in Singapore.
Shijing Xiao, Qishan Liu, Zuolian Cheng, Yingmin Liu, Jeremy Tan