Schlumberger Technology Corporation

Khooi Tan

Gary John Tustin

Trevor Lloyd Hughes

Slaheddine Kefi

Valerie Lafitte

Robert Seth Hartshorne

Shiyi Wang

Thomas Cochet

A process for hydraulic fracturing of a subterranean reservoir formation penetrated by a wellbore includes pumping a fracturing fluid or other aqueous fluid from the surface via the wellbore and into the reservoir. This fluid is an aqueous suspension of particles which each comprise an oilfield chemical distributed within an encapsulating matrix of water-insoluble carrier material. The encapsulating matrix is chosen so as to provide a delayed release of the oilfield chemical from the particles into surrounding fluid, such that oilfield chemical is liberated from the particles after they have entered the fracture. The encapsulating matrix may be a polymer which is at least partially amorphous, with a glass transition temperature below the reservoir temperature.

Use of encapsulated chemical during fracturing

Delivery of a substance to a subterranean location is achieved by suspending the substance as nanoparticles in a carrier fluid in which the substance is insoluble. First a dispersible powder composition, is formed by dissolving the substance in a solvent, emulsifying the resulting solution as the dispersed phase of an emulsion, and freeze-drying the emulsion to a powder. On mixing the powder with a fluid in which the substance is insoluble, the insoluble substance becomes a dispersion of nanoparticles which is pumped to the subterranean location. At the subterranean location a tracer dispersed as nanoparticles may migrate from injected water into hydrocarbon in a hydrocarbon reservoir. Another possibility is that the carrier fluid contains polymer and the dispersed nanoparticles comprise an agent which participates in cross-linking and consequent viscosification of the polymer at the subterranean location.

Delivery of nanodispersions below ground

Growing community of inventors

Coton, United Kingdom

Khooi Tan