Abstract: A method of treating a wellbore that includes circulating a wellbore fluid in the wellbore, wherein the wellbore fluid comprises an oleaginous base fluid and a wellbore additive colloidal solid material, and wherein the wellbore additive colloidal solid material is formed by grinding a solid particulate material and a polymeric dispersing agent for a sufficient time so that the polymeric dispersing agent is absorbed to the surface of the resulting colloidal solid particles and less than 10% of the resulting colloidal solid particles have a diameter greater than 10 microns, but not more than five percent of the particles are less than 0.2 micron in diameter, wherein the grinding is carried out in the presence of an oleaginous base fluid and wherein the grinding is carried out so that the wellbore additive colloidal solid material has a weight average particle diameter d50 less than 2.0 microns.

Abstract: A method of controlling the pressure of a casing annulus in a subterranean well that includes injecting into the casing annulus a composition including a base fluid and a polymer coated colloidal solid material. The polymer coated colloidal solid material includes: a solid particle having an weight average particle diameter (d50) of less than two microns, and a polymeric dispersing agent coated onto the surface of the solid particle during the cominution (i.e. grinding) process utilized to make the colloidal particles. The polymeric dispersing agent may be a water soluble polymer having a molecular weight of at least 2000 Daltons. The solid particulate material may be selected from materials having of specific gravity of at least 2.

Abstract: A method of formulating a wellbore fluid that includes grinding a solid particulate material and a polymeric dispersing agent to provide a resulting polymer coated solid material, and suspending the resulting polymer coated solid material in the wellbore fluid. At least a portion of the resulting polymer coated solid material has a particle diameter less than 2.0 microns, wherein the polymeric dispersing agent has a molecular weight greater than 10,000. Exemplary starting materials for the solid material include weighting agents including barite, calcium carbonate, dolomite, ilmenite, hematite or other iron ores, olivine, siderite and strontium sulfate as well as mixture and combinations of these and other similar weighting materials. The dispersant in one illustrative embodiment is a polymeric acrylate ester made from the monomers of stearyl methacrylate, butylacrylate, and acrylic acid.

Abstract: A method of formulating a wellbore fluid that includes grinding a solid particulate material and a polymeric dispersing agent to provide a resulting polymer coated solid material, and suspending the resulting polymer coated solid material in the wellbore fluid. At least a portion of the resulting polymer coated solid material has a particle diameter less than 2.0 microns, wherein the polymeric dispersing agent has a molecular weight greater than 10,000. Exemplary starting materials for the solid material include weighting agents including barite, calcium carbonate, dolomite, ilmenite, hematite or other iron ores, olivine, siderite and strontium sulfate as well as mixture and combinations of these and other similar weighting materials. The dispersant in one illustrative embodiment is a polymeric acrylate ester made from the monomers of stearyl methacrylate, butyacrylate, and acrylic acid.

Abstract: A method of controlling the pressure of a casing annulus in a subterranean well that includes injecting into the casing annulus a composition including a base fluid and a polymer coated colloidal solid material. The polymer coated colloidal solid material includes: a solid particle having an weight average particle diameter (d50) of less than two microns, and a polymeric dispersing agent coated onto the surface of the solid particle during the cominution (i.e. grinding) process utilized to make the colloidal particles. The polymeric dispersing agent may be a water soluble polymer having a molecular weight of at least 2000 Daltons. The solid particulate material may be selected from materials having of specific gravity of at least 2.

Abstract: A wellbore fluid having an oleaginous phase and an additive for increasing the density of the wellbore fluid. The additive comprises solid colloidal particles coated with a dispersant coated onto the colloidal particle during the comminution process of forming the particles. Exemplary starting materials for the colloidal particles include commonly known weighting agents including barite, calcium carbonate, dolomite, ilmenite, hematite or other iron ores, olivine, siderite, and strontium sulfate as well as mixture and combinations of these and other similar weighting materials. The dispersant in one illustrative embodiment, is selected from carboxylic acids of molecular weight of at least 150 Daltons.

Abstract: A method of treating a wellbore that includes circulating a wellbore fluid in the wellbore, wherein the wellbore fluid comprises an oleaginous base fluid and a wellbore additive colloidal solid material, and wherein the wellbore additive colloidal solid material is formed by grinding a solid particulate material and a polymeric dispersing agent for a sufficient time so that the polymeric dispersing agent is absorbed to the surface of the resulting colloidal solid particles and less than 10% of the resulting colloidal solid particles have a diameter greater than 10 microns, but not more than five percent of the particles are less than 0.2 micron in diameter, wherein the grinding is carried out in the presence of an oleaginous base fluid and wherein the grinding is carried out so that the wellbore additive colloidal solid material has a weight average particle diameter d50 less than 2.0 microns.

Abstract: A method of controlling the pressure of a casing annulus in a subterranean well that includes injecting into the casing annulus a composition including a base fluid and a polymer coated colloidal solid material. The polymer coated colloidal solid material includes: a solid particle having an weight average particle diameter (d50) of less than two microns, and a polymeric dispersing agent coated onto the surface of the solid particle during the comminution (i.e. grinding) process utilized to make the colloidal particles. The polymeric dispersing agent may be a water soluble polymer having a molecular weight of at least 2000 Daltons. The solid particulate material may be selected from materials having of specific gravity of at least 2.68 and preferably the solid particulate material may be selected from barium sulfate (barite), calcium carbonate, dolomite, ilmenite, hematite, olivine, siderite, strontium sulfate, combinations and mixtures of these-and other similar solids.

Abstract: A wellbore fluid including a peroxide degradable polymer and an encapsulated peroxide source. The peroxide degradable polymer may be a polysaccharide. The peroxide source may include an inorganic peroxide, including zinc and alkaline earth metal peroxides, such as magnesium peroxide. The encapsulating material may be a polymer, including enteric polymers. The release of peroxide, from peroxide sources generally, can be controlled by means of pH such that peroxide source can be activated, and peroxide released, by a change in pH. In a wellbore, this pH change can be effected by using produced fluids to lower the pH of a more basic wellbore fluid.

Abstract: A wellbore fluid having an oleaginous phase and an additive for increasing the density of the wellbore fluid. The additive comprises solid colloidal particles coated with a dispersant during the comminution process of forming the particles. Exemplary starting materials for the colloidal particles include commonly known weighting agents as well as mixture and combinations thereof. The dispersant in one embodiment, is selected from carboxylic acids of molecular weight of at least 150 Daltons. Alternatively, the dispersant coating may be made of compounds including oleic acid, polybasic fatty acids, alkylbenzene sulfonic acids, alkane sulfonic acids, linear alpha-olefin sulfonic acid or the alkaline earth metal salts of any of the above acids, and phospholipids as well as mixtures and combinations of these compounds. In another embodiment the dispersant is a polyacrylate ester having an average molecular weight from about 10,000 Daltons to about 200,000 Daltons.

Abstract: A wellbore fluid including a peroxide degradable polymer and an encapsulated peroxide source. The peroxide degradable polymer may be a polysaccharide. The peroxide source may include an inorganic peroxide, including zinc and alkaline earth metal peroxides, such as magnesium peroxide. The encapsulating material may be a polymer, including enteric polymers. The release of peroxide, from peroxide sources generally, can be controlled by means of pH such that peroxide source can be activated, and peroxide released, by a change in pH. In a wellbore, this pH change can be effected by using produced fluids to lower the pH of a more basic wellbore fluid.

Abstract: A low molecular weight, high melting point, crystalline, oil soluble additive for use in wellbore fluids is provided that is preferably a ground crystalline material of melting point over 80° C., preferably over 100° C. which is readily soluble in produced hydrocarbons such as crude oil and lighter condensates, and which exhibits a molecular weight of less than 1000, and preferably less than 500, and more preferably less than 300. Its particle size can be adjusted to bridge efficiently across different pore size formations and control its solubility rate.

Abstract: A wellbore fluid having an oleaginous phase and an additive for increasing the density of the wellbore fluid. The additive comprises solid colloidal particles coated with a dispersant coated onto the colloidal particle during the comminution process of forming the particles. Exemplary starting materials for the colloidal particles include commonly known weighting agents including barite, calcium carbonate, dolomite, ilmenite, hematite or other iron ores, olivine, siderite, and strontium sulfate as well as mixture and combinations of these and other similar weighting materials. The dispersant in one illustrative embodiment, is selected from carboxylic acids of molecular weight of at least 150 Daltons.

Abstract: A method of controlling the pressure of a casing annulus in a subterranean well that includes injecting into the casing annulus a composition including a base fluid and a polymer coated colloidal solid material. The polymer coated colloidal solid material includes: a solid particle having an weight average particle diameter (d50) of less than two microns, and a polymeric dispersing agent coated onto the surface of the solid particle during the cominution (i.e. grinding) process utilized to make the colloidal particles. The polymeric dispersing agent may be a water soluble polymer having a molecular weight of at least 2000 Daltons. The solid particulate material may be selected from materials having of specific gravity of at least 2.

Abstract: An additive which increases the density of wellbore fluids used during the construction or repair of oil, gas, injection, water or geothermal wells comprises solid colloidal particles of weight average particle diameter (D50) of less than 2 microns, the particles being deflocculated by the action of a dispersant, preferably incorporated during the process of grinding or communication of the particles to the specified particle size. The additives may be used in any wellbore fluid such as drilling, cementing, completion, packing, work-over (repairing), stimulation, well killing and spacer fluids as well as in a dense media separating fluid or in a ship's ballast fluid.

Abstract: A wellbore fluid including a peroxide degradable polymer and an encapsulated peroxide source. The peroxide degradable polymer may be a polysaccharide. The peroxide source may include an inorganic peroxide, including zinc and alkaline earth metal peroxides, such as magnesium peroxide. The encapsulating material may be a polymer, including enteric polymers. The release of peroxide, from peroxide sources generally, can be controlled by means of pH such that peroxide source can be activated, and peroxide released, by a change in pH. In a wellbore, this pH change can be effected by using produced fluids to lower the pH of a more basic wellbore fluid.

Abstract: There is disclosed a biodegradable wellbore fluid having a continuous oil phase comprising an n-alk-1-ene having from 12 to 20 carbon atoms or a linear polyunsaturated olefin having one of the double bonds in the 1-position and having from 12 to 22 carbon atoms, or a mixture thereof.