Synergistic Collaboration between a Viscosity Reducer and a Surfactant for in Situ Emulsion Formation to Enhance Heavy-Oil Recovery

Abstract

In situ emulsion formation is an effective nonthermal method to improve conventional heavy-oil recovery. In this paper, a newly designed viscosity reducer (TPVR7) and a high-performance surfactant (dioctyl sodium sulfosuccinate, DSS) for enhanced conventional heavy-oil recovery have been introduced and evaluated. A dewatering rate test, emulsion droplet size measurement, multiple-light scattering, and interfacial tension measurement are carried out to evaluate the synergistic effect of the viscosity reducer and the surfactant on the emulsion stability and efficiency in enhancing heavy-oil recovery. The results show that adding a surfactant can significantly increase the emulsion stability by decreasing the size of the emulsion droplet and forming a tighter interfacial film. The optimum viscosity reducer−surfactant system is formulated as TPVR7-0.5% + DSS-0.5%. With the optimum system, the viscosity of heavy oil decreased from 350 to 9 mPa•s. The equilibrium interfacial tension of the oil/TPVR7-0.5% + DSS-0.5% solution is ∼0.092 mN/m, much lower than that of the oil/TPVR7 solution. The mechanisms of synergistic collaboration between the viscosity reducer and the surfactant include enhanced emulsion stability, viscosity reduction, and interfacial tension reduction. The sand-pack flooding experiments show that a viscosity reducer and surfactant could improve heavy-oil recovery by 21.89% after water flooding at the optimum concentration, which indicates that viscosity reducer and surfactant flooding has great potential to enhance heavy-oil recovery.

Minimização De Deslocamento De Operadores Por Meio De Agrupamento De Ferramentais Em Arranjos Físicos Posicionais

“…Estudos mostram que surfactantes eficientes podem reduzir significativamente a tensão interfacial. A baixa eficiência de diminuição da viscosidade e a perda de material por adsorção nas rochas, são os principais fatores que restringem uma melhor recuperação por inundação de surfactantes convencionais (WANG et al, 2020).…”

Effect of Composition and Interfacial Tension on the Rheology and Morphology of Heavy Oil-In-Water Emulsions

“… 27 , 28 An interesting example of silica nanoparticles with a grafted polymer allowed the authors to reversibly stabilize, recover, and break O/W emulsions via pH variation. 29 Surfactant–polymer (see, for instance ref 21 , 30 , 31 ). Surfactant–polymer–nanoparticle systems.…”

“…The majority of researchers used silica particles. , An interesting example of silica nanoparticles with a grafted polymer allowed the authors to reversibly stabilize, recover, and break O/W emulsions via pH variation Surfactant–polymer (see, for instance ref ,, ). Surfactant–polymer–nanoparticle systems. The latter system was synthesized on the basis of silica nanoparticle and implemented for the O/W emulsion stabilization in ref .…”

Molecular Design of the Amphiphilic Polymer as a Viscosity Reducer for Heavy Crude Oil: From Mesoscopic to Atomic Scale

“…The forming supramolecular network structure increased the wrapping ability of the solution and exhibited excellent performance in reducing the oil−water interfacial tension. Wang et al 26 designed a new amphiphilic polymer (TPVR7), in which polyalkane and oxyvinyl were used as oleophilic and hydrophilic groups, respectively. Meanwhile, they employed TPVR7 and dioctyl sodium sulfosuccinate together to enhance heavyoil recovery owing to the better hydrophilic property of the sulfonic acid group in the latter.…”