Patent ID: 8293686
Filing Date: 2012-10-23
Classification: C09K

Abstract:
1. A process for making a water-based, emulsified drilling fluid containing emulsified bitumen from oil sand cuttings, said process comprising the steps of: (a) providing a primary fluid comprising water, a viscosity agent, and one or more surfactants having HLB numbers equal to or greater than approximately 7 but not exceeding approximately 13; and (b) mixing the primary fluid with cuttings produced by drilling through oil sand formations containing bitumen, by circulating the primary fluid through the annular space of a wellbore drilled through an oil sand formation; wherein said one or more surfactants comprise a nonyl phenol 4 mole ethoxylate and are effective to emulsify the bitumen from oil sand cuttings produced during drilling, and the emulsified bitumen becomes substantially uniformly dispersed within the primary fluid, thereby forming the emulsified drilling fluid.