Employing a strong emulsifier / de-emulsifier to the oily sludge emulsions from many industries, including oil re-refining, collection points for disposable waste oils, petrochemical plants, crude oil storage, process operations, deballasting, tank cleaning services, and oil spills at sea, will augment the reclamation of saleable oil while preventing water pollution.
Recovery makes it possible to reuse valuable oil for reprocessing, reformulating, or recovery of energy through burning. The application of Dew emulsifier / de-emulsifier reduces the amount of emulsified, oily sludge which must be trucked out, landfilled, or disposed of in other ways (all of which are costly).
The heavier hydrocarbon fractions accumulate on bottom to kill plant and animal life when released to surface waters. Dissolved or emulsified fractions act as toxic agents depleting the oxygen content of water. Floating fractions create fire hazards, and coat banks and boat hulls. They also contaminate the water, interfering with fishing and recreation.
In municipal waste treatment systems, excessive oily wastes interrupt treatment processes, interfere with disposal plant operations, and clog sewer lines. Excess oily wastes will inhibit natural biological activities in the treatment plant, requiring the plant to re-seed their bacterial colonies with a selected, specially adapted product to re-activate the system. It is therefore desirable and necessary to reduce the amount of oily wastes entering the waste treatment facility.
In the case of a crude oil spill, the primary concern is with heavy hydrocarbon emulsions. This includes asphaltenes, paraffins, and tar. Usually, the higher the temperature of the oily waste, the easier it is to separate the oil from the water.
Seawater acts as a natural emulsifier, increasing the viscosity of the oil-water waste which makes it difficult to pump the waste from the barges to shore tanks for processing. Reclaimed oil, refinery crudes, and slops often contain chemical emulsions which have been stabilized by inorganic impurities, viscosity stabilizers, etc.
An emulsion is the intimate two-phase mixture of oil and water, with one phase dispersed, as minute globules, inside the other. These minute globules are stabilized by the interfacial film, so that the globules cannot coalesce, and do not respond to gravity settling. Dual emulsions, where oil globules surrounded by water (oil-in-water) and water globules surrounded by oil (water-in-oil) coexist, may be encountered. These dual combinations are sometimes referred to as onion skin emulsions. Improper treatment of either type may invert the emulsion to the opposite type.
An interfacial film exists as a complex mixture of dissolved and colloidal matter, together with suspended solids and may be highly viscous, gelatinous and/or may possess an electrical charge. The stability of an emulsion is a function of the stabilizing agents and properties of the interfacial film, such as film viscosity and electrical charge, not of the degree of dispersion. The relative magnitude of surface tension, on each side of the interfacial film, determines the type of emulsion formed, whether oil-in-water or water-in-oil. Stability of the emulsion is also affected by the nature, and quantity, of emulsifying agents added. The interfacial film bends in the direction of the higher interface-to-liquid surface tension, enveloping the liquid on that side.
Heating the oil-water emulsion is not generally recommended when light fuels such as gasoline, jet fuel, kerosene, and other solvents are present and could present a fire hazard, especially aboard ship.
Chemicals are effective in breaking emulsions when the interface surface tension on each side of the interface is balanced or reversed, stabilizing electrical charges are neutralized, and/or emulsifying agents are precipitated. The resulting clarification, or emulsion breaking, is believed to result from the destruction of the emulsifying agents by neutralizing or reversing interfacial film electrical charges, and in turn, by agglomeration of the precipitated floc, and adsorption of the suspended oily matter on the floc surface.
When the recovered oily hydrocarbons (gasoline, jet fuel, miscellaneous solvents, heavy fuels and tars) are especially valuable, complete separation of water and oil is essential. Dew products are oil miscible, remaining with the oil while effectively releasing water and solids.
Dew products destabilizes the oil-water interface surrounding each water particle in the emulsion, replacing the emulsifier molecules (if any), which allows the water to coalesce. The process is assisted by moderate heat, which speeds the destabilization, and, by reducing the viscosity of the oil, promotes the rapid separation of the water by gravity or centrifugation. Treatment will resolve the emulsified oily sludge into free oil, water, and settle able solids.
Dew products are recommended for breaking emulsions in oil spill clean-up, tank-cleaning slop operations, separator skimming’s, and for other difficult water oil emulsion breaking requirements. Dew offers effective, consistently successful and inexpensive. The effectiveness should be considered from an overall point of view and the water layer can be cleaned up and remediated, following the emulsion breaking step, prior to its release into a natural water stream or municipal sewer system.
For all your Oil emulsification/De-emulsification need you may contact your nearest Dew representative.