042

Title:

Remediation of Passaic River Sediments Using Ultrasound and Ozone Nanobubbles

Discipline: Civil and Environmental Engineering

Presenter:

Shaini Aluthgun Hewage

Abstract:

An in-situ remediation method developed based on low-frequency ultrasound and ozone nanobubbles to remediate heavily contaminated Passaic River sediments. Ultrasound decontaminates the absorbed contaminants from the soil surface and keeps the soil in suspension due to sonophysical effects, while the ozone in the solution oxidizes and degrades desorbed contaminants. Ozone delivered as nanobubbles enhanced the ozone concentration and increased the retention time in the solution, which improved the treatment efficiency. Several laboratory tests performed to evaluate the performance of ozone nanobubbles, the impact of ultrasound on solution properties, and treatment efficiency based on the proposed method. Simulated dredge sediment made of a synthetic soil contaminated with a known quantity of contaminants was used to evaluate the proposed technology. The experimental setup consists of four stages, (1) decontaminates the soil contaminated by Polycyclic Aromatic Hydrocarbons (PAHs), (2) decontamination of inorganic contaminants (the heavy metal Chromium) in sediments, (3) the combined contamination of both PAHs and one inorganic contaminant (Chromium) in the same sediment and (4) the actual Passaic River sediments. This poster will present stage 1 and 2 results. Results showed, added ozone nanobubbles significantly enhanced the treatment efficiency compared to ultrasound alone. The maximum treatment efficiency was recorded as 91.50% and 97.5% for PAH and Chromium, respectively, by using ozone nanobubbles and 240 minutes of ultrasound application with 2minutes pulse irradiation.

Author(s):

Jay N. Meegoda

Funding Acknowledgements:

US National Science Foundation Award #1634857