Effect of organic alkali, n-alkanol, and nonionic surfactant ternary compound system on viscosity reduction of viscous crude oil

To reduce the viscosity of viscous crude oil and flow resistance, the effect of a ternary compound system including organic alkali, n-alkanol, and nonionic surfactants on viscous crude oil viscosity reduction was studied. The results showed that n-alkanol effectively reduced the droplet size of an emulsion and the viscosity of viscous crude oil and improved the fluidity of viscous crude oil. Of the low-carbon n-alkanols, n-pentanol has the best viscosity-reducing effect. The organic alkali avoids the phenomenon of fouling and corrosion caused by inorganic alkali and reacts with the acidic macromolecular components in viscous crude oil to generate alkanolamides, which produce synergistic effects with nonionic surfactants and reduce the interfacial tension between oil and water. In the ternary compound of organic alkali, n-alkanol, and nonionic surfactant, the viscosity reduction effect of viscous crude oil is significantly enhanced compared with that of a single reagent. The viscosity reduction rate of viscous crude oil of the diethanolamine ternary compound system reached 98.1% and was the best choice by experimental validation. It is shown that a reasonable formula of compound system and dosage can significantly reduce the viscosity of viscous crude oil.