Chemical Treating Agents

Objective/Goal: The goal of this project was to develop acoustic techniques to measure the droplet size distribution for subsea release of crude oil and dispersants in the presence of natural gas. It built off of the results of ARA's previous proof-of-concept study for using ultrasound to assess dispersant efficacy by measuring oil droplet sizes. In this project, ARA added the additional variable of natural gas to advance their measurement technology to separate the responses from oil droplets and natural gas bubbles in a subsea plume.

This project addressed the operational performance of subsurface injection of dispersants into deepwater blowouts by developing methods focused on oil transport after dispersant injection by researching the following:

The objective of this project is to use existing, novel equipment for obtaining fundamental, crosscutting chemical, physical, and hydrodynamic information on fluids that could be released and transported from deep, subsea hydrocarbon reservoirs and inadvertently released into a deepwater environment. Specifically, the research will use the resulting fundamental information in numerical, thermodynamic, and plume models to comprehensively describe potential roles and impacts of gas hydrates in such a scenario. The goal is to have a comprehensive understanding of:

The goal of this proof-of-concept project was to develop novel ultrasonic scattering methods to measure the droplet size of dispersed oil to provide technologies to monitor the efficacy of subsea dispersant application. ARA developed ultrasonic measurements to determine the crude oil droplet size of dispersed oil to monitor/determine the efficacy of dispersants as a function of oil type, dispersant type, dispersant-to-oil ratio, water temperature, oil temperatures, and the presence of sediment on the effectiveness of dispersants.

This project is a direct continuation of Project 638 Chemical Dispersant Research at Ohmsett: Phase 2. The objective of the research is to advance the state of the art and knowledge in chemical dispersant use in marine spill applications. Three separate projects will be conducted: Validation of Time Window for Dispersant Use Model
Comparison of Small Scale Dispersant Testing Methods to Ohmsett Results: The Effects of Dispersant Type and Oil Properties

The objective of this research was to evaluate the feasibility of using herders to enable in situ burning as a rapid-response technique in open water. This research was accomplished by performing experiments in the laboratory with the US Navy's hydrocarbon based herder formulation and the best silicone herder formulation to find the most effective product for various water temperatures.

The research investigated the feasibility of enhancing the de-emulsifying properties of commercially available oil dispersants by modifying the composition and fraction of polar constituents in the oil phase of water-in-oil emulsions and increasing the pH of the emulsion aqueous phase.

The following tasks were accomplished during the research effort:

BOEMRE has entered into an Interagency Agreement with the U.S. Environmental Protection Agency (EPA) to conduct laboratory dispersant effectiveness tests (DE) using the Baffled Flask Test (BFT) on twenty crude and fuel oils using the dispersant Corexit 9500.

The objective of the project was to study the mechanism by which oil viscosity limits the effectiveness of dispersants. Specifically, two viscosity issues were studied. One was the ability of the dispersant to penetrate into viscous oil upon initial application prior to being washed away by surface water. The other was the internal visco-elasticity of the oil-dispersant mix (in conjunction with the dispersant dosage that has successfully mixed into the oil) that may prevent the oil from being broken into droplets when wave energy is applied.

There is a need for research information and data on the effectiveness of chemical dispersants to answer questions and data gaps posed by BOEMRE regional offices, regulators and decision makers. A review of oil spill dispersants, their efficacy and effects, recently completed by the U.S. National Research Council (NRC 2005), recommended that research on chemical dispersants be conducted in several different areas.