Chemical demulsification of natural petroleum emulsions of Assam (India)

Abstract

About one third petroleum production of every oil field is in the form of water in oil emulsions which are normally stabilized by the nickel and vanadium porphyrins from asphaltene portion of crude. The petroleum emulsions of Assam oil fields which have been taken for the present work, are stabilized by the organometallic compounds of iron and high molecular weight compounds from asphaltenes. There is least possibility of any change on these natural petroleum emulsions. The Assam oil field emulsions have been tried to be broken by polyoxyethylene alkyl phenols, their sulphonates and sodium sulphonates in different combinations. The nonyl and octyl phenols with 30 and 40 molecules of ethylene oxide are found most suitable demulsifiers for Lakwa, Rudrasagar and Galeki (Assam) oil fields emulsions. The effect of polyoxyethylene alkyl phenols followed by the treatment of polyvalent cations had been studied for the first time in the field of demulsification of natural petroleum emulsions. This new combination has shown the best results as this broke even the most stable petroleum emulsions which could not be broken by polyoxyethylene alkyl phenols alone. In the present paper a simple method for calculating the chemical demulsification efficiency and a factor H/S paralleled to HLB & H/L for evaluating the emulsification property of surface active agents, have been introduced.

Separation and Determination of Diol Pollutants Come from Demulsifier in the Produced Water of Oil Fields

“…groups have been studied as demulsifiers during last thirty years all over the world, out of which polyoxyehtylene substituted alkyl phenols are found of wide use. 7 By demulsification of crude oils, the produced water is separated as a by-product of the oil production from underground reservoirs. In the first stages of processing of the production platforms, the this water is decanted from the oil, and has generally been discharged to the sea, while contains a lot of hazardous chemicals.…”

Synthesis and Preliminary Demulsification Efficiency Evaluation of New Demulsifiers Based on Fatty Oils

“…Such demulsifiers alter the oil-water interfacial properties and water droplets size. Attempts have been made to correlate demulsifier performance and some properties like molecular structure, hydrophilic-lipophilic balance (HLB), interfacial tension, interfacial viscosity, partition coefficient, dynamic interfacial tension and relative solubility number, [1][2][3][4][5][6][7][8][9] but no generalized conclusions have been determined. The selection of the suitable demulsifier for a certain oil emulsion stills a practical art.…”

Effect of Demulsifiers on the Separation of Water-in-Oil Emulsions

“…Complete knowledge of how the demulsifiers destabilise the naturally occuring emulsifiers is not clear. It is believed that (Sharma et al, 1982;Jones et al, 1978) the large surface activity of the demulsifiers not only cripples the action of the emulsifiers, but also helps in expelling them from the oil-water interface. Sizeable literature exists on the studies of the effect of demulsifiers on petroleum emulsions from various sources.…”

“…Sizeable literature exists on the studies of the effect of demulsifiers on petroleum emulsions from various sources. Most of these studies (Sharma et al, 1982) elucidate the idea that the surface active demulsifier molecules migrate towards the oil-water interface and change the orientation of the hydrophillic and hydrophobic groups of the emulsifiers. Investigations explaining the effect of demulsifiers on the sedimentation as well as the coalescence of the dispersed droplets with themselves and their homophase are relatively scanty.…”