Advances in Treating Agents for Oil Spill Response with Applicability to the Arctic

Amy Tidwell & Tim Nedwed, ExxonMobil Upstream Research Company

Ian Buist & Randy Belore, SL Ross Environmental Research, Ltd.

Gerald Canevari, Canevari & Associates

2012 United States-Canada Northern Oil and Gas Research ForumAnchorage, Alaska

November 13-15, 2012

Outline

• The OSR Toolbox• Dispersants

− Background

− Development of New Dispersant• In situ Burning

− Background

− Development of Herding Agents• Commercialization Plans • Summary

Spill Response Options: The Toolbox

Mechanical Recovery: Booms & Skimmers

In-Situ Burning

Monitor & Evaluate

Dispersants

The goal is to design a response strategy based on

Net Environmental Benefit Analysis

Background on Dispersants: What are they?

• Dispersants are solutions of surfactants dissolved in a solvent

• Surfactants reduce oil-water interfacial tension – allows slicks to disperse into very small droplets with minimal wave energy

• Dispersed oil rapidly dilutes to concentrations <10 ppm within minutes, <1 ppm within hours, ppb range within a day

Background on Dispersants: What are they?

• Oil-degrading micro-organisms are present everywhere

• Each dispersed oil droplet is a concentrated food source that is rapidly colonized and degraded by marine bacteria

• Rapid dilution allows biodegradation to occur without nutrient or oxygen limitations

• Rapid dilution reduces toxicity issues – dispersed oil plume dilutes to <1 ppm in hours and <1 ppb within 1 – 2 days

Graphic consistent with Venosa & Holder, EPA 2007

Development of New Dispersant Gel

•Consistency of warm honey•Positively buoyant drops•Cohesive & persistent•Oleophilic behavior•85+% active ingredient

Properties of Dispersants Used in Testing

Dispersant

Dispersant Viscosity (15C)Density @ 20C

(g/cc)Viscosity (cP) Shear Rate (s-1)

Corexit 9500 107 100 0.968

New dispersant 1500 10 0.921

Gel Pour Video

9500 Pour Video

Development of New Dispersant: Testing

Dispersant-effectiveness results for light, medium, & heavy crude oils

• Controlled burning of oil “in situ”• Conventional process requires booms to keep oil thick• Fire resistant booms are a challenge to transport• Only operational use offshore during Deepwater Horizon

Background on in situ Burning

Newfoundland Offshore Burn Experiment, 1993

• Herders enable in situ burning without booms• Requires application of small volume of surfactant on water surface on

perimeter of slick• Herding process requires minutes to thicken slick enough to burn• Herder application and burn initiated quickly from a single helicopter

Background on in situ Burning: Herding Agents

Lab-scale application of herders

Development of Herders: Recent Testing

Field testing of herding agents, 2008

• Herder testing since 2004 focused on supporting in situ burning in ice• Recent field tests were done in very limited ice supporting use of

herders in open water

Commercialization Efforts: New Dispersant and Herders

• Dispersant gel

− Plans are for dispersant gel to be available for sale by early 2013

• Herding agents

− Currently listed with US EPA for potential use in US marine waters

− Commercially available through Applied Fabrics, Buffalo, New York

− Helicopter delivery system under final development

Summary and Conclusions

• Two new treating agent technologies – new dispersant and herding agents – have been developed which could enhance oil spill response capabilities

• New dispersant

− Treated light-to-medium oils with 2/3 less dispersant than a currently available product

− Dispersed viscous oils that were previously considered un-dispersible

• Herding Agents

− Potential to enable in situ burning in both ice conditions and open water without the need for fire-resistant booms

− May turn an infrequently used response option into a readily available tool because it can be applied rapidly from helicopters

Questions

Slide 13

Background on Dispersants

Dispersants Enhance Removal of Oil from the Environment Through Biodegradation