Presentation
A Proposed Approach to Measure Oil Removal Efficiency by Surface Washing Agents in the Laboratory
DescriptionOver 50 surface washing agents (SWAs) are listed on the National Contingency Product Plan Schedule (NCPPS) with no current protocol to measure their effectiveness in removing weathered oil from shorelines. The US EPA is developing a testing protocol to determine the influence of different parameters on SWA performance, which involves artificially weathering Alaskan North Slope oil on stainless-steel discs and adding SWA products to lift the oil from the substrate. Gravimetric analysis is used to determine the amount of oil removed by the SWA and remaining on the substrate.
In this study, 20 SWAs listed on the NCPPS were evaluated and showed widely varying effectiveness. The repeatability (Sr) and reproducibility (SR) of the protocol itself was evaluated with five SWA products and a no product added control on three separate days. Efficient products showed higher protocol variability (SR of 9.2-15.8% ), while inefficient products and controls showed lower variability (SR of 2.2-4.4%) across the three test days. The h-statistic, which describes the deviation of each trial from the overall mean for any given product, was used to confirm statistical similarity of the three trials. Based on these results, the protocol was found to be repeatable and reproducible for the products investigated and conditions used. Further investigations of protocol parameters, such as mix time, turbulence, contact time, salinity, SWA to oil ratio, and temperature, will be conducted to further differentiate SWA product performance. A standardized testing method could serve as an initial screening tool for SWAs and determine their appropriateness for oil spill remediation.
Disclaimer: The views expressed in this article are those of the authors and do not necessarily reflect the opinions or policies of the U.S. EPA. This publication does not constitute an endorsement of any commercial product.
In this study, 20 SWAs listed on the NCPPS were evaluated and showed widely varying effectiveness. The repeatability (Sr) and reproducibility (SR) of the protocol itself was evaluated with five SWA products and a no product added control on three separate days. Efficient products showed higher protocol variability (SR of 9.2-15.8% ), while inefficient products and controls showed lower variability (SR of 2.2-4.4%) across the three test days. The h-statistic, which describes the deviation of each trial from the overall mean for any given product, was used to confirm statistical similarity of the three trials. Based on these results, the protocol was found to be repeatable and reproducible for the products investigated and conditions used. Further investigations of protocol parameters, such as mix time, turbulence, contact time, salinity, SWA to oil ratio, and temperature, will be conducted to further differentiate SWA product performance. A standardized testing method could serve as an initial screening tool for SWAs and determine their appropriateness for oil spill remediation.
Disclaimer: The views expressed in this article are those of the authors and do not necessarily reflect the opinions or policies of the U.S. EPA. This publication does not constitute an endorsement of any commercial product.
Authors
Environmental Microbiologist
Project Manager
Ecologist
Event Type
Paper
TimeWednesday, May 15th3:30pm - 3:50pm CDT
Location288-290
Restoration