Influence of polymers on the stability of Gudao crude oil emulsions

The influence of different types and concentrations of polymers on the stability of Gudao crude oil emulsion was investigated by measuring the volume of water separated from the emulsions and the interracial shear viscosity of the oil/water interfacial film.Experimental results indicate that the simulated water-in-oil emulsion with 40 mg/L of partially hydrolyzed polyacrylamide (HPAM) 3530S could be easily broken by adding demulsifier C and was readily separated into two layers.However,HPAM AX-74H and hydrophobically associating water-soluble polymer (HAP) could stabilize the crude oil emulsion.With increasing concentration of AX-74H and HAP,crude oil emulsions became more stable.Water droplets were loosely packed in the water-in model oil emulsion containing HPAM 3530S,but water droplets were smaller and more closely packed in the emulsion containing AX-74H or HAP.The polymers could be adsorbed on the oil/water interface,thereby increasing the strength of the interfacial film and enhancing the emulsion stability.