HIGH TEMPERATURE STABLE FLUID LOSS CONTROL SYSTEM

摘要

HIGH TEMPERATURE STABLE FLUID LOSS CONTROL SYSTEM of the Invention The present invention is directed to a high temperature stable composition capable of imparting a combination of pseudoplasticity and fluid loss control properties to aqueous systems. The composition is a combination of: (a) a solid, particulate silicate or alumino-silicate material; (b) a chemical compound capable of converting to a higher oxidation state under alkaline conditions; and (c) a reaction product of a polymeric substance selected from polyvinyl alcohol or hydroxyalkyl cellulose reacted with at least 1 percent of stoichiometry of a cross-linking agent selected from an epihalohydrin or an aldehyde containing or generating agent; wherein the amount of component (a) is at least 75 wt. percent of component (c) and component (b) is at least 25 wt. percent of component (c). The invention is further directed to improved drilling fluids containing said composition and to the process of drilling bore holes using said improved fluid.