STABILITY AND RHEOLOGY OF HEAVY CRUDE OIL-IN-WATER EMULSION STABILIZED BY AN ANIONIC- NONIONIC SURFACTANT MIXTURE

A crescente demanda de energia associada ao declínio progressivo das reservas de óleos convencionais (óleo extraleves, leves e médios) têm estimulado a exploração de campos de óleos pesados e extra-pesados. Porém, por conta de diversas características intrínsecas destes óleos, explorá-los, transportá-los e refiná-los ainda são desafios a serem vencidos. Dessa forma, o presente trabalho teve como objetivo apresentar uma revisão bibliométrica sobre os principais agentes emulsificantes que vêm sendo empregados na estabilização de emulsões de óleo pesado em água (O/A), com fins de melhorar o escoamento desses óleos nas condições de superfície (fluxo em tubulações). A busca foi realizada utilizando as plataformas Science Direct, One Petro e Web of Science, inserindo as seguintes palavras-chaves: Heavy crude oil; Oil-in-water emulsion; Stability; Pipeline transportation. A abrangência temporal foi limitada em 10 anos (2011-2020) e, na sequência, os critérios de inclusão/exclusão foram aplicados, de modo a refinar a busca. Como resultado foi obtido um total de 18 artigos científicos. Dentre os países que apresentaram maior interesse no tema, podemos destacar a Índia, a Noruega, o México, a China, os Estados Unidos e o Irã. Em relação aos emulsificantes mais empregados na estabilização de emulsões O/A os surfactantes e as partículas sólidas foram os mais citados. Embora os surfactantes não iônicos tenham sido apontados como os mais eficientes, ainda são necessários estudos mais detalhados para entender o mecanismo de atuação destes agentes, bem como avaliar a capacidade destes compostos de estabilizar emulsões O/A em condições de escoamento em superfície.

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Optimization and evaluation of reduced graphene oxide hydrogel composite as a demulsifier for heavy crude oil-in-water emulsion

Chinese Journal of Chemical Engineering ◽

10.1016/j.cjche.2020.08.027 ◽

2020 ◽

Author(s):

Kin Kit Fong ◽

Inn Shi Tan ◽

Henry Chee Yew Foo ◽

Man Kee Lam ◽

Adrian Chiong Yuh Tiong ◽

...

Keyword(s):

Graphene Oxide ◽

Crude Oil ◽

Reduced Graphene Oxide ◽

Heavy Crude Oil ◽

Water Emulsion ◽

Hydrogel Composite ◽

Oil In Water ◽

Reduced Graphene ◽

Heavy Crude ◽

Oil In Water Emulsion

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The effect of non-ionic surfactant on the internal corrosion for X52 steel in extra-heavy crude oil-in-water emulsions

Anti-Corrosion Methods and Materials ◽

10.1108/acmm-03-2017-1770 ◽

2018 ◽

Vol 65 (3) ◽

pp. 234-248 ◽

Cited By ~ 3

Author(s):

L.M. Quej-Ake ◽

A. Contreras ◽

Jorge Aburto

Keyword(s):

Crude Oil ◽

Steel Surface ◽

Corrosion Process ◽

Ionic Surfactant ◽

Heavy Crude Oil ◽

Content Type ◽

Oil In Water ◽

X52 Steel ◽

Emulsion Systems ◽

Heavy Crude

Purpose The purpose of this research is to study different extra-heavy crude oil-in-water emulsions that can be found in practice for corrosion process of X52 steel adding 60 mg.L-1 of non-ionic surfactant and a corrosion inhibitor (CI). Electrochemical impedance spectroscopy and Tafel plots are carried out. Thus, Bode-modulus and Bode-phase angle plots are discussed. Adsorption isotherms obtained from corrosion rate (CR) values are taken into account. Design/methodology/approach Two-electrode arrangement is used to characterize the pseudo-capacitance values for X52 steel exposed to water and crude oil phases, mainly. Electrochemical evaluations for X52 steel exposed to extra-heavy crude oil-in-water emulsions are recorded in a conventional three-electrode cell to study the corrosion process as was documented in detail by Quej-Ake et al. (2015). Therefore, all electrodes are placed as close as possible to eliminate the iR-drop. Findings Pseudo-capacitance analysis shows that X52 steel immersed in oilfield produced water was more susceptible to corrosion than that immersed in ocean water solution and extra-heavy crude oil phase. After being analyzed, the X52 steel surface coverage and adsorption process for surfactant and CI could be concluded that surfactant could protect the metal surface. In a coalescence extra-heavy crude oil-in-water emulsion, the water medium generated a new solution that was more corrosive than the original water phase. Wash crude oil process was provoked in emulsion systems to sweep up the salts, mainly. Thus, corrosive species that can be recovered inside extra-heavy crude oil may appear, and in turn a new more corrosive solution could be obtained. Taking into account the straight line obtained in Bode-modulus plot for X52 exposed to extra-heavy crude oil, it is possible to point out that the negative value of the slope or R2 can be related to a coefficient (Jorcin et al., 2006). It is important to mention that electrochemical responses for X52 steel exposed to extra-heavy crude oil-in-water under coalescence emulsions revealed that corrosion and diffusion processes exist. Therefore, a possible good inhibitor is surfactant in emulsion systems. Originality/value CR and anodic and cathodic slopes suggest that the surfactant acted as mixed CI. Of these, susceptible anodic (MnS and perlite or cementite) and cathodic (ferrite) sites on steel surface could be affected, due to which physicochemical adsorption could happen by using electrochemical parameters analysis. Thus, no stable emulsions should be taken into account for extra-heavy crude oil transportation, because corrosion problems in atmospheric distillation process of the crude oil due to stable emulsion cannot be easily separated. In this manner, coalescent emulsions are more adequate for transporting extra-heavy crude oil because low energy to separate the water media is required.

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