Abstract: The rheological characteristics of aqueous well drilling fluids are improved by incorporating into the fluids a small amount of a sulfonated styrene-itaconic acid copolymer.

Abstract: A stabilized fracturing fluid and a method of stabilizing a fracturing fluid containing at least one of guar gum and its derivatives is disclosed, wherein at least one stabilizing compound selected from the thiol derivatives of heterocyclic compounds is added to the fracturing fluid. This method of stabilization prevents degradation of the fracturing fluid, i.e., reduction in its rheological properties at high temperatures and permits smooth practice of the fracturing operation.

Abstract: Waterflooding process for the recovery of oil from a subterranean formation in which at least a portion of the injected water is thickened by the addition of a mixture of sulfonated polyethoxylated aliphatic alcohol surfactants. The thickened water has a salinity within the range of 5-18 percent. The mixture of sulfonated polyethoxylated aliphatic alcohols has an HLB within the range of 10.0-14.0 and the lipophilic base of the surfactant mixture contains an average of from 16 to 20 carbon atoms. The surfactant mixture incareases the viscosity of the water to a value greater than viscosity achieved through the addition of only one of the surfactant components.

Abstract: Shale-stabilizing drilling fluids for use in connection with subterranean well drilling operations. The drilling fluids contain polyvalent metal/guanidine complexes, especially aluminum/guanidine complexes, and preferably contain guanidinium ion and aluminate ion accompanied by (a) cationic starches and (b) a glycol selected from the group consisting of polybutylene glycol, polyethylene glycol, polypropylene glycol and mixtures thereof.

Abstract: A spacer fluid for use in oil well drilling applications is disclosed. The fluid is prepared from a slurry comprising 25-60% heteropolysaccharide S-130, 0.5-6% organophilic clay, 30-70% solvent, up to 10% surfactant, and up to 6% methanol or isopropanol.

Abstract: Compositions intended to be reacted with hydrogen peroxide to produce chemiluminescent light are disclosed wherein the compositions contain an oxalate and a fluorescer comprising 9,10-bis(4-methoxyphenyl)-2-chloroanthracene. A perylene dye may also be incorporated.

Abstract: This invention relates to a composition and method of temporarily reducing the permeability of subterranean formations penetrated by a wellbore. In particular, it relates to an inexpensive, low molecular weight condensation product of hydroxy acetic acid with itself or compounds containing other hydroxy-, carboxylic-acid-, or hydroxycarboxylic-acid moieties and method for preventing fluid loss during well treatment.

Abstract: A well drilling and completion fluid having a potassium salt of a copolymer of (a) acrylic acid, or an .alpha.-substituted acrylic acid and (b) acrylate ester having the general formula CH.sub.2 .dbd.CH--COOR where R is an alkyl or hydroxyalkyl having 1 to 4 carbon atoms and substituted R groups; and an accelerator catalyst composed of water, KOH, lignite, sulfonated polystyrene, and, optionally, a vinylsulfonate/vinylamide polymer.

Abstract: A combination corrosion/scale inhibitor composition for use in oil or gas wells is provided which is in the form of a substantially homogeneous dispersion so as to facilitate use and well coverage of the composition, and to minimize well downtime. The overall composition preferably includes a preblend having an imidazoline-based corrosion inhibitor and an organophosphonic scale inhibitor, together with an organic solvent and an alkylphenol ethoxylate surfactant; the preblend is then field-mixed with water or crude oil to yield a final treating composition. In practice the final composition may be introduced into the well in bulk or over time so as to achieve full coverage of down-hole equipment with both the corrosion and scale inhibitor.

Abstract: Sacrificial agents employed in methods of obtaining oil from rock formations by surfactant flooding comprising oxidized and/or chlorinated lignin and lignin-like derivatives obtained form inexpensive and readily available sources. In one form of the invention such derivatives present in E-stage wood pulp bleach plant effluent are concentrated by the use of macroporous resins, reverse osmosis or membrane dialysis. In another form of the invention, new sources of the derivatives are provided from forest industry by-products. In a further form of the invention, the derivatives are complexed with iron which significantly improves the sacrificial agent activity of the derivatives. Such sacrificial agents reduce the amount of expensive surfactant required in the oil recovery method.

Abstract: On occasion, during drilling operations employing oil base drilling muds, conditions occur that cause the surface of the solid materials in the mud to be water wet, changing the rheology of the drilling mud such that it is unusable and has to be discarded. In accordance with this invention, a novel method is provided to reverse this condition so that the water wet surfaces of the solid particles become oil wet again, restoring the drilling mud to substantially its original condition or level or to such a condition that it can continue to be used in drilling operations. This is accomplished by adding to the drilling mud containing water wet particles at least one of a specific and critical group of imidazolines.The imidazolines may be added to stable oil mud drilling fluids to decrease possible water wetting of the particle surfaces therein.

Abstract: An aqueous drilling fluid having present in an amount sufficient to disperse the fluid and to provide resistance to high temperatures and solids contamination of the drilling fluid, at least one salt of a polymer or copolymer of acrylic or methacrylic acid with alkanolamine, alkylamine, mixtures of alkanolamine and alkylamine, mixtures of lithium and alkanolamine, mixtures of lithium and alkylamine and mixtures of lithium, alkanolamine and alkylamine, the polymer having a weight average molecular weight of between about 2,000 and about 15,000 and a pH of from about 6 to about 8.5 and where mixtures of lithium and alkanolamine, lithium and alkylamine or mixtures of lithium, alkanolamine and alkylamine are used, the amount of lithium is present to give from about 30% to about 70% of the desired neutralization of the polymer and the alkanolamine and/or alkylamine is present to give from about 70% to about 30% of the desired neutralization of the polymer.

Abstract: A plasma reactor comprises a working chamber, the chamber being adapted to receive at least one article and a volume of plasma which is capable of interacting with a material of the article. A pair of electrodes are positioned about the chamber. Further, a radio-frequency generator is provided. More particularly, the plasma reactor includes a radio-frequency voltage transformer. The transformer includes a primary winding that is connected to the generator and a secondary winding the center of which is grounded. The secondary winding is adapted to transform the energy received from the primary winding into plasma-exciting energy at the electrodes, whereby the voltage between the plasma and the ground is small such that voltage discharge between the plasma and any grounded parts is minimized. The plasma reactor can be used to strip photoresist, etch silicon dioxide, aluminum and polysilicon from semiconductor wafers.

Abstract: A process for decolorizing iron-caused yellow color in brine solutions comprising adding a small amount of a soluble metal salt such as alugenite to the brine solution, neutralizing the solution and then filtering the solution to obtain a solution of a desired degree of clarity.

Abstract: A drilling fluid additive comprises high pyruvate xanthan and locust bean gum in a weight ratio of about 40:60 to 80:20. The additive increases the viscosity of the drilling fluid at low shear, has improved thermal stability, and increases the capacity of the fluid to suspend high density weighting materials.

Abstract: In an aqueous drilling fluid, an improved thinning effect is obtained by adding a first agent comprising a mixture of a sulfoalkylated tannin or polyvalent metal complex thereof with a lignite, optionally in combination with a second agent comprising a metal compound of chromium, titanium, iron, zinc, strontium or magnesium which is at least partially soluble in water.

Abstract: The disclosed invention is a novel drilling fluid additive for use in reducing lost circulation in wellbores and a method for employing the invention additive for reducing such lost circulation. The invention additive is a highly oil absorbent polymer encapsulated by a reaction-preventive protective casing to prevent the polymer from expanding by absorbing oil until it is desired to breach the casing. The reaction-preventive protective casing may be a film which will dissolve after a desired time of residence in the borehole or a film or clay which can be ruptured in the formation, releasing the oil absorbent polymer to expand by absorbing oil. The substantially expanded polymer will seal off their zones and fissures, reducing lost circulation.

Abstract: An acidizing composition and method for slowly dissolving siliceous material by the slow production of very low concentrations of hydrofluoric acid is provided by this invention. The continual generation of very low concentrations of hydrofluoric acid is accomplished by the hydrolysis of hexafluorotitanate-containing compounds. The acidizing composition is particularly useful and advantageous for the solubilization of siliceous clay in or adjacent the pores of subterranean hydrocarbon formations thereby increasing the permeability of said formations. Because of the very low concentration of hydrofluoric acid in the acidizing composition solubilization of siliceous clay deposits is possible at relatively large distances from the point of injection into the formation, for acidizing formations which are too sensitive for more reactive acidizing compositions, for acidizing formations containing chlorite clays, and/or for acidizing formations having an elevated temperature including formation temperatures of 125.

Abstract: A method of treating a carbonate-containing subterranean formation to increase the production of hydrocarbons therefrom. The formation is contacted with an aqueous solution of one or more of certain anionic aminophosphonate compounds whereby the composition is caused to be absorbed onto the solid surfaces present in the subterranean limestone-containing formation and substantially reduces the tendency of such surfaces from becoming water or hydrocarbon wet.

Abstract: A drilling fluid capable of coagulating shale particles, when used for well drilling, completion or the like, comprising a low solids fluid containing polymeric viscosifiers and polymeric fluid loss reducers as well as a high molecular weight organic polycationic polymeric coagulant and flocculant.