Testing the Effectiveness of Spill-Treating Agents: Laboratory Test Development and Initial Results

Abstract

Laboratory effectiveness tests have been developed for four classes of spill treating agents: solidifiers, demulsifying agents, surface-washing agents, and dispersants. Many of the currently available treating agents in these four categories have been tested for effectiveness. These results are presented. Solidifiers or gelling agents change liquid oil to a solid. Tests show that these require a large amount of agent to solidify oil, ranging from 16 percent by weight to over 200 percent. Demoussifiers or emulsion breakers are used to prevent or reverse the formation of water-in-oil emulsions. A newly developed effectiveness test shows that only one product is highly effective. However, many products will work, but require large amounts of spill treating agent. Surfactant-containing materials are of two types, surface-washing agents and dispersants. Testing has shown that an agent that is a good dispersant is conversely a poor surface-washing agent, and vice versa. Tests of surface washing agents show that only a few agents have effectiveness of 25 to 40 percent, where this effectiveness is defined as the percentage of oil removed from a test surface. Extensive work has been done on dispersant testing and comparison of laboratory tests. All laboratory tests will yield the same effectiveness value if the oil-to-water ratio is about 1:1,000 or greater, and if a settling time of 10 or more minutes is employed. Extensive results using the “swirling flask” testare reported. Heavy oils show effectiveness values of about 1 percent, medium crudes of about 10 percent, light crude oils of about 30 percent, and very light oils of about 90 percent.

Silicone‐based polymers as oil spill treatment agents

“…The problem often cited by oil spill responders using natural or synthetic sorbents and solidifiers is the difficulty of recovering and recycling oil from the sorbents or the polymers [7]. Although some sorbents can be squeezed and reused [12], silicone polymer residues are not reusable and must be treated.…”

“…Oil-treatment agents can be divided into three distinct categories: dispersants and surface-washing agents, emulsion breakers, and gelling agents or solidifiers [7]. Dispersants are chemical formulations of ionic and neutral surfactants, usually dissolved in hydrocarbon-based solvents, that have the capacity to decrease the water-oil interfacial tension and promote the dispersion of tiny oil droplets into the underlying water mass [8].…”

“…Emulsion breakers or demulsifiers are chemical agents that can prevent the formation of break-down water-in-oil emulsions. Most of these agents are hydrophilic surfactants that tend to quickly leave the oil layer and cannot be used successfully in open waters [7].…”

Oil spill treating agents

“…Emulsion breakers have been tested for their performance [52,53]. Emulsion breakers have been tested for their performance [52,53].…”

Separation of oil from oily wastewater by sorption and coalescence technique using ethanol grafted polyacrylonitrile

“…Even very low concentrations of oils can be toxic to microorganisms responsible for biodegradation in conventional sewage processes [1]. Many methods have been studied for oil removal so far [2][3][4][5]. The use of various sorbents is the most common technique to treat floating oil on water surface because of the possibility of its collection and reuse [6].…”