摘要 |
<p>Viscosifying compositions having reduced toxicity are used in treatment fluids in subterranean operations; methods include providing such treatment fluids including a viscosifying composition and an aqueous base fluid, the viscosifying composition including hydroxyethyl cellulose, about 10% to about 60% by weight of 2-pyrrolidone, and about 10% to about 60% by weight of a water soluble monoalkyl ether of propylene glycol having substantially no swelling effect on the hydroxyethyl cellulose, wherein a weight ratio of hydroxyethyl cellulose to 2-pyrrolidone is in a range from about 1 : 2 to about 2.6: 1 and the method including placing the treatment fluid in a subterranean formation.</p> |