Effect of ammonium-containing polyalkyl acrylate on the rheological properties of crude oils with different ratio of resins and waxes

• A new composite additive for oil pipeline pumping has been obtained and tested.
• A method for obtaining an additive is proposed including neutralization of unconverted monomer and catalyst with higher amine.
• The effectiveness of the composite additive as a viscosity modifier and depressant is evaluated.
• The activation energies of viscous flow and internal energies of the destruction of supramolecular structures were calculated.

A composite additive for oil pipeline pumping has been tested as a viscosity modifier and crystallization modifier (depressant) in two crude oils and gas condensate of West Siberian deposits with the different content of resins and waxes. The additive represents a toluene solution of a cationic surfactant and an amphiphilic copolymer of alkyl acrylate C16-C20 with a salt of acrylic acid and higher amine. Pour points, rheological characteristics, phase transition temperatures, energies of the destruction of supramolecular structures were determined for investigated oils with different concentrations of the additive. The comparison of the efficiency was made for the composite additive, a commercial depressant and surfactant-free additive.