Improving properties of bilge water’s treatment sludge in a port reception facility by novel continuous ultrasonic reactor

Abstract

The main problem faced by facilities dealing with bilge water treatment is the generation of a high sludge amount, which has significant contents of oil and hazardous substances. The presence of petroleum and petroleum-derived organic oil, which ranges from 10 to 20% in bilge water with varying characteristics not only poses challenges in treating the bilge water but also complicates the management of the bilge water treatment sludge. Hence, this study aims to improve the characteristics of treatment sludge generated after bilge water treatment at one of Turkey’s largest port waste reception facilities (PRF), consisting of a combined process involving ultrasound and a filter press. When the filter press was used to reduce the water content in the sludge cake to approximately 65%, a similar water content of about 65% was achieved by employing ultrasound as a pre-treatment, even when the initial sludge contained 95–98% water. Additionally, the application of ultrasound before the filter press did not have a significant impact on the values of total organic carbon (TOC) and loss on ignition (LOI). However, the value of dissolved organic carbon (DOC) decreased by 45% when subjected to sonication for 60 minutes at a density of 100 W/L. Furthermore, when ultrasound was applied as a pre-treatment, an increase in the sonication duration resulted in improvements of 10% and 22% in the parameters of total dissolved solids (TDS) and chloride, respectively, which were influenced by different levels of ultrasonic power. Briefly, such research has been novelly conducted on the management of bilge water treatment sludge. Ultrasound, which is often preferred in sludge dewatering applications, was applied to this type of sludge for the first time, and the studies were conducted in a pilot-scale facility and a real PRF field. In conclusion, the partially promising results of this study will provide a new alternative and a pioneering guide for the treatment of bilge water sludge.