Abstract: A wellbore fluid comprises an aqueous carrier liquid, hydrophobic particulate material suspended therein and a gas to wet the surface of the particles and bind them together as agglomerates. The hydrophobic particulate material has a specified maximum particle size and/or minimum surface area: namely a volume median particle size d50 of not more than 200 micron, determined as median diameter of spheres of equivalent volume and/or a surface area of at least 30 m2 per litre (0.03 m2 per milliliter), determined as surface area of smooth spheres of equivalent volume. The agglomeration of the particles by gas leads to the formation of agglomerates which contain gas and so have a bulk density lower than the density of the particles. This reduces the rate of settling. The fluid is particularly envisaged as a slickwater fracturing fluid in which the suspended particles are proppant.

Abstract: A wellbore fluid comprises an aqueous carrier liquid, hydrophobic particulate material suspended therein and a gas to wet the surface of the particles and bind them together as agglomerates. The hydrophobic particulate material has a specified maximum volume median particle size d50 of not more than 200 micron, and/or a minimum surface area of at least 30 m2 per liter. Agglomerates of the particles contain gas and so have a bulk density lower than the density of the particles. This reduces the rate of settling. The fluid is particularly envisaged as a slickwater fracturing fluid in which the suspended particles are proppant. The small particle size and/or substantial surface area increases the amount of gas which can be retained within agglomerates and so enhances the buoyancy of the agglomerates. The end result is that a greater proportion of a hydraulic fracture is propped open.

Abstract: Gravel packing a region of a wellbore is carried out using one or more hydrophobically-surfaced particulate materials as the gravel. Placing the gravel pack is carried out using an aqueous carrier liquid, with hydrophobic particulate material suspended in the liquid and a gas to wet the surface of the particles and bind them together as agglomerates. The presence of gas lowers the density of the agglomerates relative to the particulate material in them, so that transport of the particulates is improved. The invention enables the placing of longer, uniformly packed, gravel packs, especially in horizontal and near horizontal wellbores.

Abstract: A wellbore fluid is an aqueous carrier liquid with first and second hydrophobic particulate materials suspended therein. The first hydrophobic particles have a higher specific gravity than the second hydrophobic particles and the fluid also comprises a gas to wet the surface of the particles and bind them together as agglomerates. The fluid may be a fracturing fluid or gravel packing fluid and the first particulate material may be proppant or gravel. The lighter second particulate material and the gas both reduce the density of the agglomerates which form so that they settle more slowly from the fluid, or are buoyant and do not settle. This facilitates transport and placement in a hydraulic fracture or gravel pack. One application of this is when fracturing a gas-shale with slickwater. The benefit of reduced settling is better placement of proppant so that a greater amount of the fracture is propped open.

Abstract: A wellbore fluid comprises an aqueous carrier liquid, hydrophobic fibers suspended therein, hydrophobic particulate material also suspended in the carrier liquid, and a gas to wet the surfaces of the particles and fibers and bind them together as agglomerates. The wellbore fluid may be a slickwater fracturing fluid and may be used for fracturing a tight gas reservoir. Using a combination of hydrophobic particulate material, hydrophobic fibers and gas inhibits settling out of the particulate material from an aqueous liquid. Because the gas acts to wet the surfaces of both materials and agglomerates them, the particulate material is made to adhere to the fibers; the fibers form a network which hinders settling of the particulate material adhering to them, and the agglomerates contain gas and so have a bulk density which is less than the specific gravity of the solids contained in the agglomerates.

Abstract: Solid material required at a subterranean location is supplied from the surface suspended in a carrier liquid and agglomerated below ground by means of a binding liquid. To achieve agglomeration, the binding liquid and the particulate solid are similar to each other but opposite to the carrier liquid in hydrophilic/hydrophobic character. The solid and the binding liquid may both be hydrophobic while the carrier liquid is hydrophilic, or vice versa. The solid may be hydrophobically surface modified to render it hydrophobic. The binding liquid may be provided as a precursor which converts to the binding liquid below ground to trigger agglomeration after arrival at the subterranean location. The agglomerates may function as proppant heterogeneously placed in a fracture of a reservoir, or may serve to block an unwanted path of flow. The binding liquid may polymerise after agglomeration so as to stabilise and strengthen the agglomerates.

Abstract: A wellbore fluid comprises an aqueous carrier liquid, hydrophobic particulate material suspended therein and a gas to wet the surface of the particles and bind them together as agglomerates. The hydrophobic particulate material has a specified maximum particle size and/or minimum surface area: namely a volume median particle size d50 of not more than 200 micron, determined as median diameter of spheres of equivalent volume and/or a surface area of at least 30 m2 per liter (0.03 m2 per milliliter), determined as surface area of smooth spheres of equivalent volume. The agglomeration of the particles by gas leads to the formation of agglomerates which contain gas and so have a bulk density lower than the density of the particles. This reduces the rate of settling. The fluid is particularly envisaged as a slickwater fracturing fluid in which the suspended particles are proppant.

Abstract: Gravel packing a region of a wellbore is carried out using one or more hydrophobically-surfaced particulate materials as the gravel. Placing the gravel pack is carried out using an aqueous carrier liquid, with hydrophobic particulate material suspended in the liquid and a gas to wet the surface of the particles and bind them together as agglomerates. The presence of gas lowers the density of the agglomerates relative to the particulate material in them, so that transport of the particulates is improved. The invention enables the placing of longer, uniformly packed, gravel packs, especially in horizontal and near horizontal wellbores.

Abstract: A wellbore fluid comprising an aqueous carrier liquid, hydrophobic fibers suspended therein, hydrophobic particulate material also suspended in the carrier liquid, and a gas to wet the surfaces of the particles and fibers and bind them together as agglomerates. The wellbore fluid may be a slickwater fracturing fluid and may be used for fracturing a tight gas reservoir. Using a combination of hydrophobic particulate material, hydrophobic fibers and gas inhibits settling out of the particulate material from an aqueous liquid. Because the gas acts to wet the surfaces of both materials and agglomerates them, the particulate material is made to adhere to the fibers; the fibers form a network which hinders settling of the particulate material adhering to them, and the agglomerates contain gas and so have a bulk density which is less than the specific gravity of the solids contained in the agglomerates.

Abstract: A wellbore fluid is an aqueous carrier liquid with first and second hydrophobic particulate materials suspended therein. The first hydrophobic particles have a higher specific gravity than the second hydrophobic particles and the fluid also comprises a gas to wet the surface of the particles and bind them together as agglomerates. The fluid may be a fracturing fluid or gravel packing fluid and the first particulate material may be proppant or gravel. The lighter second particulate material and the gas both reduce the density of the agglomerates which form so that they settle more slowly from the fluid, or are buoyant and do not settle. This facilitates transport and placement in a hydraulic fracture or gravel pack. One application of this is when fracturing a gas-shale with slickwater. The benefit of reduced settling is better placement of proppant so that a greater amount of the fracture is propped open.

Abstract: Solid material required at a subterranean location is supplied from the surface suspended in a carrier liquid and agglomerated below ground by means of a binding liquid. Agglomeration is achieved by arranging that the binding liquid and the particulate solid are similar to each other but opposite to the carrier liquid in hydrophilic/hydrophobic character. The solid and the binding liquid may both be hydrophobic while the carrier liquid is hydrophilic, or vice versa. The solid may be hydrophobically surface modified to render it hydrophobic. The binding liquid may be provided as a precursor which converts to the binding liquid below ground to trigger agglomeration after arrival at the subterranean location. The agglomerates may function as proppant heterogeneously placed in a fracture of a reservoir, or may serve to block an unwanted path of flow. The binding liquid may polymerise after agglomeration so as to stabilise and strengthen the agglomerates.