Feasibility study for the treatment of shipboard generated oily wastewaters

The operation of ocean-going vessels, particularly tankers, results in the generation of certain types of oily wastes. The three principal categories of such wastewaters are 1) ballast water, 2) tank cleaning slops and 3) bilge water. Due to ever increasingly stringent pollution control regulations, discharges from ships must be of a sufficiently high quality to comply with legal standards in regards to oil content. The vessel operator must equip his ship with a system capable of treating the oily wastewaters. In this thesis, the author examines the feasibility of using various physical/chemical processes as oil/water separation techniques. The treatment system had to function as an emulsion breaker as well since the action of ship motion and cleaning devices and pumps produces mechanical oil and water emulsions. A filtration technique was studied and proved satisfactory within the limits of research. Oil removal can be accomplished producing effluents with oil concentrations less than 15 parts per million. The use of deep bed dual media filtration as a polishing device following gravity settling appears to be a promising application. Recommendations for further research are made to refine the technique.Civil and Environmental Engineering, Department o