Removing fines from a spent aqueous well treating fluid

摘要

Method of removing fines from a spent aqueous drilling fluid containing, a water-soluble polymer, a salting-out anion, fines and a slightly soluble calcium or magnesium compound comprising the steps of (a) raising the pH of the aqueous drilling fluid to allow agglomeration of the fines and precipitation of the water-soluble polymer; and (b) separating the agglomerates from the aqueous drilling fluid.