Abstract:
The following describes a novel and alternative mechanism in regards to releasing reactive chemicals. Namely, utilizing shells containing multiple emulsions that can be blended with the base fluids, and then react with said base fluid upon exposure to a trigger e.g. high shear and/or elongation flow, therefore plugging even large fractures. Such gelling lost circulation material allows to obtain a reliable carrier and fast reaction when triggered.
Abstract:
The invention provides a composition made of fibers and a material able to exhibit reverse solubility. The invention preferably is used in a well and as a method to cure lost circulation.
Abstract:
A cement slurry composition is described as having cement, water, and organic polymeric particles. The composition also includes non-ionic surfactants, which may contain ethoxylate groups or contain both ethoxylate groups and propyxlate groups in the hydrophilic part. The non-ionic surfactant acts to disperse the hydrophobic polymeric particles in the slurry and to reduce or prevent foaming. The cement slurry composition is prepared and then pumped into the subterranean well and placed in a zone of the subterranean well. Time is then allowed for the cement slurry composition to set into a solid mass in the zone.
Abstract:
A method of treating a subterranean formation, the method including placing a well treatment fluid comprised of at least an enzyme and a breaker additive in the subterranean formation. Initially, the pH of the well treatment fluid is about 11.5. The breaker additive reduces the pH of the well treatment fluid by at least 1.5 to increase the activity of enzyme and accelerate hydrolysis of a crosslinkable component.
Abstract:
Method for controlling lost circulation in a subterranean well using oil-dispersible lost-circulation materials which comprise fibers that are coated (or sized) with a lipophilic coupling agent, a lipophilic film-forming polymer or both. The fibers are preferably between about 6 mm and about 25 mm long, and between about 10 μm and about 200 μm in diameter. The fibers may be added to carrier fluids comprising oil-base fluids, synthetic-base fluids, invert-emulsion-base fluids and combinations thereof. The preferred fiber concentration in the carrier fluid is between about 0.55 g/L and about 28.5 g/L. The carrier fluid may be a drilling fluid, a spacer fluid or a lost-circulation pill.
Abstract:
A cement slurry composition is described as having cement, water, and organic polymer particles. The composition also includes non-ionic surfactants, which may contain ethoxylate groups or contain both ethoxylate groups and propoxylate groups in the hydrophilic part. The non-ionic surfactant acts to disperse the hydrophobic polymeric particles in the slurry, thereby reducing mixing time. The cement slurry composition is prepared and then pumped into the subterranean well and placed in a zone of the subterranean well. Time is then allowed for the cement slurry composition to set and form a solid mass in the zone.
Abstract:
Mixtures of fibers and solid particles are effective for curing fluid losses and lost circulation in a subterranean well. Stiff fibers are more effective than flexible ones; however, mixtures of stiff and flexible fibers have a synergistic effect. The quantity and particle-size distribution of the solids are optimized according to the stiffness, dimensions and concentrations of fibers.
Abstract:
Treatment fluids and methods for treating a subterranean formation include introducing a treatment fluid into a subterranean formation, the treatment fluid containing a nanocrystalline cellulose. The treatment fluid may be a fracturing fluid, well control fluid, well kill fluid, well cementing fluid, acid fracturing fluid, acid diverting fluid, a stimulation fluid, a sand control fluid, a completion fluid, a wellbore consolidation fluid, a remediation treatment fluid, a spacer fluid, a drilling fluid, a frac-packing fluid, water conformance fluid or a gravel packing fluid.
Abstract:
A method of treating a subterranean formation, the method including placing a well treatment fluid comprised of at least an enzyme and a breaker additive in the subterranean formation. Initially, the pH of the well treatment fluid is about 11.5. The breaker additive reduces the pH of the well treatment fluid by at least 1.5 to increase the activity of enzyme and accelerate hydrolysis of a crosslinkable component.
Abstract:
Methods for curing lost circulation in a subterranean well comprise the use of a first and a second lost circulation material. The first lost circulation material is added during the initial preparation of a process fluid. The second process fluid is added to the process fluid at a later time as the process fluid is being pumped into the subterranean well. The first lost circulation may comprise granular or lamellar particles or both. The second lost circulation material may comprise fibers, ribbons or both.