Abstract: Aqueous and substantially anhydrous fluids having particularly low thermal conductivities and variable densities are disclosed. The fluids include: one or more organic and/or inorganic salts and at least one aprotic polar organic solvent, a mixture of aprotic and protic polar organic solvents, and/or a polar organic solvent having both protic and aprotic polar functional group linkages. The fluids optionally include one or more viscosifying agents and are free of cross-linking agents. Methods for formulating and using the fluids are also disclosed.

Abstract: Aqueous and substantially anhydrous fluids having particularly low thermal conductivities and variable densities are disclosed. The fluids include: one or more organic and/or inorganic salts and at least one aprotic polar organic solvent, a mixture of aprotic and protic polar organic solvents, and/or a polar organic solvent having both protic and aprotic polar functional group linkages. The fluids optionally include one or more viscosifying agents and are free of cross-linking agents. Methods for formulating and using the fluids are also disclosed.

Abstract: Aqueous and substantially anhydrous fluids having particularly low thermal conductivities and variable densities are disclosed. The fluids include: one or more organic and/or inorganic salts and at least one aprotic polar organic solvent, a mixture of aprotic and protic polar organic solvents, and/or a polar organic solvent having both protic and aprotic polar functional group linkages. The fluids optionally include one or more viscosifying agents and are free of cross-linking agents. Methods for formulating and using the fluids are also disclosed.

Abstract: Aqueous and substantially anhydrous fluids having particularly low thermal conductivities and variable densities are disclosed. The fluids include: one or more organic and/or inorganic salts and at least one aprotic polar organic solvent, a mixture of aprotic and erotic polar organic solvents, and/or a polar organic solvent having both prone and aprotic polar functional group linkages. The fluids optionally include one or more viscosifying agents and are free of cross-linking agents. Methods for formulating and using the fluids are also disclosed.

Abstract: Methods are disclosed for the removal of iron from aqueous solutions. The methods involve facilitating formation of an iron salt precipitate by introducing a source of anions to the solution and adjusting the pH of the solution through the addition of one or more acids, separating the iron salt precipitate from the aqueous solution, and removing residual anions in the aqueous solution.

Abstract: A method for the controlled de-functionalization of downhole polymers comprising contacting downhole, water-dispersible, polymeric material with a dehydrating agent until the water-dispersible polymeric material is sufficiently de-functionalized to be removed. The water-dispersible polymeric material can be found in the downhole formation of a filtercake on production walls, other downhole polysaccharide materials and in fluid loss pills. The contact between the dehydrating agent and the polymeric material is prolonged until the water-dispersible, polymeric material is sufficiently de-functionalized to allow the de-functionalized material to be removed by flushing the drilling fluid. The dehydrating agent is selected from concentrated inorganic salt solutions, concentrated organic salt solutions, acid anhydrides, esters, alcohols, ethers, ketones, aldehydes, amides, organic acids and mixtures thereof.

Abstract: A method and system for selecting fluids for compatibility with specified metals exposed to oil field environments. Metal specimens are tested for corrosion and/or cracking behavior by exposing them to fluids under stressful test conditions. The testing is conducted under variable temperature, pressure, pH, fluid density, metallurgical stress, additives, cover gases and combinations thereof. The results from the stress testing are stored in a database. The test results are evaluated using encoded logic embedded in software media. Fluid compatibility evaluation software, developed from the stress test results, is executed to determine the cracking susceptibility of metals exposed to fluids under stressful conditions. A cracking susceptibility index can be developed to provide a quantitative indicator of cracking susceptibility. Fluid recommendation reports utilize the cracking susceptibility index values to rank compatible fluids. The reports also list optional additives to be used with the fluids.

Abstract: A method of monitoring corrosion in a metal sample comprising applying a physical stress to one or more metal samples, placing the metal sample under stress in a sealed vessel, adding one or more fluids to the vessel, measuring the strain on the metal sample over a specified time interval, controlling the environment inside the vessel, calculating the rate of change of the strain measurement over the specified time interval, recording the rate of change of the strain measurement, calculating a moving average of two or more previously recorded rates of change of the strain measurement, and monitoring the moving average to detect damage to the metal sample.

Abstract: A method and system for selecting fluids for compatibility with specified metals exposed to oil field environments. Metal specimens are tested for corrosion and/or cracking behavior by exposing them to fluids under stressful test conditions. The testing is conducted under variable temperature, pressure, pH, fluid density, metallurgical stress, additives, cover gases and combinations thereof. The results from the stress testing are stored in a database. The test results are evaluated using encoded logic embedded in software media. Fluid compatibility evaluation software, developed from the stress test results, is executed to determine the cracking susceptibility of metals exposed to fluids under stressful conditions. A cracking susceptibility index can be developed to provide a quantitative indicator of cracking susceptibility. Fluid recommendation reports utilize the cracking susceptibility index values to rank compatible fluids. The reports also list optional additives to be used with the fluids.

Abstract: A method for the controlled de-functionalization of downhole polymers comprising contacting downhole, water-dispersible, polymeric material with a dehydrating agent until the water-dispersible polymeric material is sufficiently degraded to be removed. The water-dispersible polymeric material can be found in the downhole formation of a filtercake on production walls, other downhole polysaccharide materials and in fluid loss pills. The contact between the dehydrating agent and the polymeric material is prolonged until the water-dispersible, polymeric material is sufficiently degraded to allow the degraded material to be removed by flushing the drilling fluid. The dehydrating agent is selected from concentrated inorganic salt solutions, concentrated organic salt solutions, acid anhydrides, esters, alcohols, ethers, ketones, aldehydes, amides, organic acids and mixtures thereof.

Abstract: A method for removing filter cake from a subterranean borehole comprising drilling the borehole with a drilling fluid that includes additives to form a filter cake having an oxidation-degradable component, preferably a polysaccharide. The filter cake is contacted with a clear brine containing a mixture of a persulfate salt in a variable density brine to degrade the polymers within the filter cake. The persulfate mixture breaks down the filter cake in well bores having temperatures ranging from about 65° F. to 165° F. Concentration of the persulfate sets the pace of the reaction.