Solid/liquid dispersions in drilling and production

Abstract

To reach the new oil and gasfields, the oil industry is developing more and more sophisticated drilling and production schemes. Wells trajectories are now deviated, horizontal, with high extended reach, multibranched, ultra deep offshore, etc. Extended reach wells are up to 10 km and offshore drilling is close to 3000 m of water depth! In these cases, drilling and production techniques are pushed to the limits. The operating conditions, the properties of the different materials employed must be controlled and operated in a more accurate way. This is the case for solid/liquid dispersions that are common in these operations: drilling fluids, cements, hydrates dispersions oil and gas phases, sand venue with reservoir fluids, etc. These mixtures present some specific properties that can be at the limit between solid or liquid behaviour. For particular conditions the solid phase can create structures able to support large stresses and in others circumstances the mixture can flow like a viscous paste. Modeling of these characteristics is not easy and needs to use knowledge of different areas: rheology, physicochemistry, hydrodynamics, thermodynamics, etc. In this revue, different systems used in the drilling and production industry will be discussed. Main properties of these systems and different development conducted by IFP will be addressed. © 2004, Institut français du pétrole.