The role of industrial polyacrylamide in petroleum extraction

The thickening, flocculation, and rheological properties of industrial polyacrylamide make it play an important role in petroleum extraction. It is widely used in drilling, water plugging, acidizing, fracturing, well washing, completion, drag reduction, scale prevention, and oil displacement.

In general, the use of polyacrylamide is to improve the oil recovery rate. Especially many oil fields have entered secondary and tertiary production, with reservoir depths generally above 1000m, and some reservoirs reaching depths of up to 7000m. The heterogeneity of the formation and offshore oil fields have posed more stringent conditions for oil extraction operations.

Among them, new requirements have also been put forward for PAM in deep oil recovery and offshore oil recovery, requiring it to be resistant to shear force, high temperature (above 100 ℃ to 200 ℃), calcium ions, magnesium ions, and seawater degradation. Since the 1980s, great progress has been made in basic research, preparation, application research, and variety development of PAM suitable for oil recovery abroad.

Industrial polyacrylamide is used as a drilling fluid modifier and fracturing fluid additive:

As a drilling fluid modifier, partially hydrolyzed polyacrylamide (HPAM) is often used, which is obtained by hydrolyzing polyacrylamide. Its function is to regulate the rheology of drilling fluid, carry rock debris, lubricate the drill bit, and reduce fluid loss. The drilling fluid formulated with polyacrylamide has a low specific gravity, which can reduce the pressure and blockage of oil and gas reservoirs, easily detect oil and gas reservoirs, and facilitate drilling. The drilling speed is 19% higher than conventional drilling fluid and about 45% higher than mechanical drilling speed.

In addition, it can greatly reduce drilling accidents, reduce equipment wear, and prevent well leakage and collapse. Fracturing technology is an important production increase measure for developing tight layers in oil fields. Fracturing fluid crosslinked with polyacrylamide is widely used due to its high viscosity, low friction, good sand suspension ability, low filtration loss, good viscosity stability, minimal residue, wide supply, convenient preparation, and low cost.

In hydraulic fracturing and acidification treatment, polyacrylamide is prepared into an aqueous solution with a concentration of 0.01% to 4% and pumped into the downhole formation to fracture the formation. Industrial polyacrylamide aqueous solution has the function of thickening sand carrying and reducing fracturing fluid loss. Moreover, polyacrylamide has a drag reducing effect, which can reduce the transmission loss of pressure.