A method comprising drilling through a plurality of differing zones of a subterranean formation using a drilling fluid comprising a non-oleaginous continuous phase, an oleaginous discontinuous phase and at least a first salt dissolved into the non-oleaginous continuous phase. The amount of the at least first salt dissolved into the non-oleaginous continuous phase is maintained such that a density of the drilling fluid varies by no more than 10% while drilling through the plurality of zones.

A method comprising drilling through a plurality of differing zones of a subterranean formation using a drilling fluid comprising a non-oleaginous continuous phase, an oleaginous discontinuous phase and at least a first salt dissolved into the non-oleaginous continuous phase. The amount of the at least first salt dissolved into the non-oleaginous continuous phase is maintained such that a density of the drilling fluid varies by no more than 10% while drilling through the plurality of zones.

A method of designing compressible particles for a fluid mixture. The compressible particles are intended to be used for attenuating pressure within a confined volume such as a trapped annulus. Preferably, the compressible particles reside buoyantly within an aqueous fluid, forming a fluid mixture. Each of the compressible particles is fabricated to collapse in response to fluid pressure within the confined volume, and comprises carbon. The particles may each have a porosity of between 5% and 40%, and a compressibility of between 10% and 30%, at 10,000 psi. The particles are tuned to have a buoyancy that is lower than the carrier fluid while still having resiliency.

A method of designing compressible particles for a fluid mixture. The compressible particles are intended to be used for attenuating pressure within a confined volume such as a trapped annulus. Preferably, the compressible particles reside buoyantly within an aqueous fluid, forming a fluid mixture. Each of the compressible particles is fabricated to collapse in response to fluid pressure within the confined volume, and comprises carbon. The particles may each have a porosity of between 5% and 40%, and a compressibility of between 10% and 30%, at 10,000 psi. The particles are tuned to have a buoyancy that is lower than the carrier fluid while still having resiliency.

A wellbore fluid comprising a first aqueous base fluid and a plurality of silica nanoparticles suspended in the first aqueous base fluid. The nanoparticles are present in the fluid in an amount to have an effect of decreasing a crystallization temperature by at least 4 to 55° F. as compared to a second aqueous base fluid without the silica nanoparticles.

A wellbore fluid comprising a first aqueous base fluid and a plurality of silica nanoparticles suspended in the first aqueous base fluid. The nanoparticles are present in the fluid in an amount to have an effect of decreasing a crystallization temperature by at least 4 to 55° F. as compared to a second aqueous base fluid without the silica nanoparticles.

Provided is an additive for a cement slurry for a well that is capable of suppressing the generation of free water and preventing flotation/separation of low-specific-gravity aggregate while securing sufficient cement strength even at a high temperature. Also provided is a method for producing this additive. This additive for a cement slurry for a well contains an aqueous dispersion of silica and a layered silicate.

A system and method for generating water concentrated in calcium bromide from produced water, to provide for drilling fluid having the calcium bromide. The technique includes flowing the produced water through a bed of ion-exchange resin to sorb bromide ions from the produced water onto the ion-exchange resin, and then regenerating the ion-exchange resin to desorb the bromide ions for combination with calcium ions to acquire an aqueous solution with calcium and bromide.

A system and method for generating water concentrated in calcium bromide from produced water, to provide for drilling fluid having the calcium bromide. The technique includes flowing the produced water through a bed of ion-exchange resin to sorb bromide ions from the produced water onto the ion-exchange resin, and then regenerating the ion-exchange resin to desorb the bromide ions for combination with calcium ions to acquire an aqueous solution with calcium and bromide.

This invention provides zinc-free aqueous brine compositions. These zinc-free aqueous brine compositions have a density of about 14.3 pounds per gallon or more, and a true crystallization temperature of about 20° F. or less, and comprise water and one or more inorganic bromide salts, with the provisos that when calcium bromide is present, one or more other water-soluble inorganic salts are also present, when lithium bromide is present, calcium bromide is absent, when bismuth(III) bromide is present, one or more other water-soluble inorganic salts are also present, and for a true crystallization temperature of about 10° F. or less, when manganese(II) bromide is present, one or more other water-soluble inorganic salts are also present.
Processes for forming these zinc-free aqueous brine compositions are also provided.