Demulsifier

A number of these stmctures are offered commercially by BASE Corporation under the trade name Tetronic polyols. The products are similar to oxygen block polymers. Although not strongly surface active per se, they are useful as detergents, emulsifiers, demulsifiers, defoamers, corrosion inhibitors, and lime-soap dispersants. They are reported to confer antistatic properties to textiles and synthetic fibers. 

Petroleum Production and Refining. Specific polyamine derivatives are used in the petroleum production and refining industries as corrosion inhibitors, demulsifiers, neutralizers, and additives for certain operations. 

Entmilzung, /. splenectomy, entmischen, v.t. i. separate into component parts, disintegrate, decompose, dissociate, segregate, unmix demulsify. 

The emulsion blocking mechanism involves formation of emulsion in the pores either by self-emulsification of water-based filtrate with the crude oil, or oil filtrate from an oil-based fluid emulsifying formation water. The emulsions are viscous and can block the pores. The remedial design is to prevent emulsification either by eliminating oil from completion fluid or by the use of demulsifiers. 

Process leaks from food and beverage production or wood leachates often produce sugars, colloidal materials, pectins, emulsions, and proteins that cause stable foams in the boiler. These lead to carryover and further steam-condensate line contamination. The temporary use of a demulsifier or defoamer as part of the water treatment program may be of particular benefit, but again the condensate is unsuitable for return to the boiler. Other process leaks include ... 

The type of oil-removing equipment used may be alum or caustic precoat coke filters, diatomaceous earth filters, or coalescing filters, sometimes employing oleophilic resins as oil strippers. Phenolic formaldehyde demulsifiers are also sometimes used. 

NOTE The orientation of surfactant molecules at an interface (water-solvent, water-gas, water-metal) confers performance characteristics on the molecule that permit it to be employed as an emulsifier, demulsifier, wetting agent, antifoam, lubricant, or other agent. 

It is not always necessary to demulsify the water, however, because when small quantities are present in fine droplet form, the water explodes at the burner firing point, improving atomization of the fuel and providing for more complete combustion. Consequently, a water-in-oil emulsifier may be used to deliberately retain the water as small, emulsified droplets. The overall effec-... 

This formulation is designed as a complete treatment, providing improved atomization and combustion, sludge dispersancy, demulsifi-cation of water from oil, prevention of bacterial slimes at the water-oil interface, reduced cold-end corrosion, and less fuel system deposits. 

Demulsifying agent Solution of a sulfonic acid, a phenolic resin, and alcohol 5 to 15... 

Effectiveness Testing. Initially, it was emphasized that oil spill-treating agents can be divided into four classes solidifiers, demulsifying agents, surfacewashing agents, and dispersants. 

In the production of crude oil, the greatest part of the crude oil occurs as a water-in-oil emulsion. The composition of the continuous phase depends on the water/oil ratio, the natural emulsifier systems contained in the oil, and the origin of the emulsion. The natural emulsifiers contained in crude oils have a complex chemical structure, so that, to overcome their effect, petroleum-emulsion demulsifiers must be selectively developed. As new oil fields are developed, and as the production conditions change at older fields, there is a constant need for demulsifiers that lead to a rapid separation into water and oil, as well as minimal-residual water and salt mixtures. 

The emulsion must be separated by the addition of chemical demulsifiers before the crude oil can be accepted for transportation. The quality criteria for a delivered crude oil are the residual salt content and the water content. For the oil to have a pipeline quality, it is necessary to reduce the water content to less than approximately 1.0%. 

At the refinery, before distillation, the salt content is often further reduced by a second emulsification with freshwater, followed by demulsification. Crude oils with high salt contents could lead to breakdowns and corrosion at the refinery. The object of using an emulsion breaker, or demulsifier, is to break the emulsion at the lowest possible concentration and, with little or no additional consumption of heat, to bring about a complete separation of the water and reduce the salt content to a minimum. 

There are oil-soluble demulsifiers and water-soluble demulsifiers, the latter being widely used. Emulsions are variable in stability. This variability is largely dependent on oil type and degree of weathering. Emulsions that have a low stability will break easily with chemical emulsion breakers. Broken emulsions will form a foamlike material, called rag, which retains water that is not part of the stable emulsions. The most effective demulsifier must always be determined for the particular emulsion. 

Demulsifiers are often added to the emulsion at the wellhead to take advantage of the temperature of the freshly raised emulsion to hasten the demulsifi-cation step. 

Demulsifiers (specifically, oil spill demulsifiers) can be applied to oil spills in low concentrations. They prevent mousse formation for significant periods of time and cause a large reduction in oil-water interfacial tension. The best of these was found to prevent emulsification at dosages as low as 1 part inhibitor to 20,000 parts of fresh oil at 20° C [273]. At dosages of 1 1000, at temperatures higher than 10° C, the chemical also results in significant and rapid dispersion of the oil. For very low temperatures or highly weathered oil, the performance of the chemical falls off sharply. 

Demulsifiers for crude oil emulsions should meet the following properties ... 

The stabilization of water-oil emulsions happens as a result of the interfacial layers, which mainly consist of colloids present in the crude oil—asphaltenes and resins. By adding demulsifiers, the emulsion breaks up. With water-soluble... 

The effectiveness of a crude oil demulsifier is correlated with the lowering of the shear viscosity and the dynamic tension gradient of the oil-water interface. The interfacial tension relaxation occurs faster with an effective demulsifier [1714]. Short relaxation times imply that interfacial tension gradients at slow film thinning are suppressed. Electron spin resonance experiments with labeled demulsifiers indicate that the demulsifiers form reverse micellelike clusters in the bulk oil [1275]. The slow unclustering of the demulsifier at the interface appears to be the rate-determining step in the tension relaxation process. 

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