A drilling fluid composition includes an aqueous base fluid, 0.01 to 5 wt. % of polyamine-functionalized activated carbon (AC-PAD), 0.1 to 10 wt. % of a shale material, 0.01 to 2 wt. % of a thickener, 0.1 to 10 wt. % of a fluid loss control additive, 0.01 to 5 wt. % of an adsorbent, and 1 to 20 wt. % of a borehole stabilizer. Each wt. % is based on a total weight of the drilling fluid composition. The AC-PAD is uniformly disposed on surfaces of the shale material. The shale material has an average pore size of 5 to 400 nanometers (nm). A method of preparing the AC-PAD and a method of drilling a subterranean geological formation.

The invention relates to a composition comprising a plant-derived cellulose particulate material comprising less than 30 wt % extractable glucose; and extractable xylose in an amount of at least 3% of the amount of extractable xylose in the starting plant material, and an agent selected from the group comprising natural ionic polymers or natural non-ionic polymers; synthetic water dispersible polymers, and/or associative thickeners, and its various uses, including as a drilling fluid.

The present invention addresses to the use of a viscous fluid in continuous pumping to contain the saline dissolution in a homogeneous way (not limited to just one type of evaporite), highlighting the results of seawater with viscosifiers, due to its simplicity, and that does not have the same impact on the logistical chain as a brine supply. The increase in fluid viscosity limits the diffusion of salt into the medium and thus better contains the dissolution of the well walls, while also promoting a laminar flow regime in the annulus of the well, variables desired to achieve the quality of the operation of cementation. The employment of viscous fluid concentrates allows on the fly dilutions with the in-line seawater fraction mixture. The technique can also employ solutions of pre-dispersed viscosifying additives which, when added to seawater, result in a substantial increase in the volume of drilling fluid produced, no longer limited by the unit tank capacity. This allows drilling large extensions of salt. The low salinity viscous fluid is used in drilling operations without fluid return to the drilling rig (riserless) in the presence of a predominantly saline formation, aiming at preserving the phase diameter and improve well construction conditions.

A method of removing hydrogen sulfide (H.sub.2S) from a subterranean geological formation using a nanocomposite material includes injecting a drilling fluid suspension with a pH of 10 or more containing a nanocomposite material in an amount of 0.01 to 1.5 percent by weight of the drilling fluid suspension into the subterranean geological formation. The nanocomposite material is a layered triple hydroxide material including copper, magnesium, iron, and a zeolitic imidazolate framework-67. The method further includes circulating the drilling fluid suspension in the subterranean geological formation and forming a water-based mud and scavenging the hydrogen sulfide from the subterranean geological formation by reacting the hydrogen sulfide with the nanocomposite material in the water-based mud.

The present invention relates to nanofibrillated cellulose (NFC) for use in drilling fluids, fracturing fluids, spacer fluids etc. The fluids contain NFC as a viscosifier with an aspect ratio of more than 100 and where the nanofibrils have a diameter between 5 and 100 nanometer and a length of more than 1 m.

A drilling fluid and method for drilling in a coal containing formation with a mixed metal-viscosified drilling fluid including at least 0.05% calcium sulfate.

A drilling fluid composition includes an aqueous base fluid, 0.01 to 10 wt. % of a date palm leaves extract (DPLE), 1 to 10 wt. % of clay particles, and 0.01 to 1 wt. % of a base, where each wt. % based on a total weight of the drilling fluid composition. The DPLE is homogenously disposed on surfaces of the clay particles. The clay particles disposed with the DPLE are present in the drilling fluid composition in the form of a composite. A pellet made from the clay particles treated with the DPLE has a swelling value at least 75% less than a swelling value of the pellet in an aqueous composition that does not contain the DLPE. A method of making the drilling fluid composition.

A drilling fluid composition includes an aqueous base fluid, 0.01 to 5 wt. % of polyamine-functionalized activated carbon (AC-PAD), 0.1 to 10 wt. % of a shale material, 0.01 to 2 wt. % of a thickener, 0.1 to 10 wt. % of a fluid loss control additive, 0.01 to 5 wt. % of an adsorbent, and 1 to 20 wt. % of a borehole stabilizer. Each wt. % is based on a total weight of the drilling fluid composition. The AC-PAD is uniformly disposed on surfaces of the shale material. The shale material has an average pore size of 5 to 400 nanometers (nm). A method of preparing the AC-PAD and a method of drilling a subterranean geological formation.

A drilling fluid composition includes an aqueous base fluid, 0.01 to 10 wt. % of a date palm leaves extract (DPLE), 1 to 10 wt. % of clay particles, and 0.01 to 1 wt. % of a base, where each wt. % based on a total weight of the drilling fluid composition. The DPLE is homogenously disposed on surfaces of the clay particles. The clay particles disposed with the DPLE are present in the drilling fluid composition in the form of a composite. A pellet made from the clay particles treated with the DPLE has a swelling value at least 75% less than a swelling value of the pellet in an aqueous composition that does not contain the DLPE. A method of making the drilling fluid composition.

The present disclosure relates to downhole fluid additives including a clay, a hydroxylated polymer, a cation, and water. The disclosure further relates to downhole fluids, including drilling fluids, spaces, cements, and proppant delivery fluids containing such as downhole fluid additive and methods of using such fluids. The downhole fluid additive may have any of a variety of functions in the downhole fluid and may confer any of a variety of properties upon it, such as salt tolerance or desired viscosities even at high downhole temperatures.