HE® 300 Polymer

HE® 300 Polymer is an inherently clean thickener, posing very little risk of formation damage under normal usage conditions. The HE® 300 Polymer is readily soluble in normal wellbore cleanup type acids. The polymer is degradable using oxidizing agents, such as sodium hypochlorite (bleach) or ammonium persulfate. The activity of the oxidizer is generally enhanced by using fluid with a basic pH. Degradation by oxidizers is also enhanced at temperatures above 125 °F.

HE® 300 Polymer has been utilized as a thickener for various brines in drilling and completions applications. The HE® 300 Polymer powder is readily dissolved in most brines, yielding rheological properties which describes the polymers performance in a 10.7 lb/gal calcium chloride brine at 70 °F.

The composition of HE® 300 Polymer provides protection against thermal hydrolysis, which allows the polymer to maintain its solubility in high temperature use and to resist precipitation in the presence of multivalent cations. In this Fan 50 test, the thickened calcium chloride brine was heated incrementally to 300 °F. The fluid was kept at each temperature for one hour before proceeding to the next stage. There was very little change in viscosity during that one-hour period, which demonstrates the polymer stability at high temperatures. Almost all the original viscosity was regained upon cool-down, again indicating no polymer degradation, hydrolysis or loss due to precipitation. In most high temperature applications, the polymer may benefit from the use of oxygen scavengers (e.g. sodium sulfite 0.5 to 4.0 lb/bbl) and a buffer like the sodium bicarbonate/carbonate system. For calcium systems calcium hydroxide is preferred.