Demulsifying of waste oils in a port reception facility by ultrasound with a new coagulant: techno-economic evaluation

Abstract

The illegal release of wash water from various ship parts has become a major source of pollution in the seas. These released wastes have oil, hydrocarbon, and oil derivatives. The toxic compounds in these wastes both adversely affect aquatic life and reach human beings by mixing into the food chain. Various international and regional agreements have been made to prevent ship-originated marine pollution. One of the sanctions imposed by a convention on member countries imposes the obligation to install waste reception facilities at ports. The main purpose of these facilities is to separate the waste oil and water from each other (demulsification) and transfer them to the relevant treatment and recovery processes. Researches in the literature to increase the efficiency of the separation processes generally focus on laboratory-scale and synthetic oil-water mixtures. This study aimed to dispose of mixed oil and petroleum-derived waste oils of a waste reception port in Istanbul/Turkey using demulsification with ultrasound and chemical process in pilot-scale. Thus, it is intended to increase dewatering efficiency and to develop a method reducing the energy requirements, maintenance, and chemical costs of the existing methods. Under-optimized experimental conditions, using the newly synthesized demulsifier, the water content of waste oil is reduced by about 7%, total operating cost was reduced by about 40% and the operating time was reduced to one-sixth. In the next planned study, confirming the data of this study in a full-scale facility, designing a full-scale ultrasound process, and effects of the new system on the organic load to wastewater treatment system after demulsification will be discussed.