What is partially hydrolyzed polyacrylamide (PHPA)?

Partially hydrolyzed polyacrylamide (PHPA) is a widely used polymer in the oil and gas industry due to its lesser cost and good water solubility. PHPA is used as a functional additive in water-based drilling fluids. The PHPA mud system stabilizes shale formations and influences cuttings and wellbore stability.

Which drilling fluid is compatible with PHPA?

It is compatible with most of the drilling fluid products, biopolymers, PAC, CMC. It maintains borehole stability by preventing shale swelling and erosion. PHPA maintains viscosity in solid free drilling fluid. As a Bentonite extender in low solids non-dispersed mud, it can be used along with small addition of Bentonite to suspend weight material.

Is PHPA a water soluble polymer?

PHPA is a co-polymer of anionic character and high molecular weight. It is a water-soluble polymer, which is primarily used as a highly efficient fluid loss reducer, Viscosifier and protective colloid for shale’s and cutting in fresh water, calcium, sodium brines and KCL mud systems.

Are flocculants the same as drilling fluids?

Interestingly, the flocculants applied are the same PHPA polymers used in drilling fluids. Flocculation is readily achieved in mineral processing applications, but residual PHPA concentrations in these slurries are exceedingly low even after dosing; contrast this to drilling fluids, with PHPA concentrations at least five orders of magnitude higher.

How does PHPA affect fluid rheology?

The introduction of higher molecular weight synthetic polymers typified by partially hydrolysed polyacrylamide (PHPA) allowed the same effect on fluid rheology to be achieved at much lower additive concentrations, a major practical advantage.

Is flocculation method suitable for PHPA test for HYPR-drill?

The flocculation method has been extensively tested in previous projects for the PHPA test of HYPR-DRILL. However, it was observed in the project that this method is unsuitable for HyPR-CAP due to the nature of its short chain PHPA.