A salt-tolerant polymer microsphere plugging agent and a preparation method thereof, the agent being made of white oil, fumed silica, acrylamide monomer, acrylic acid, sorbitan fatty acid ester, N,N′-methylene bisacrylamide, ammonium persulfate, sodium bisulfite, hydrophilic surfactant and water. The present general inventive concept synthesizes salt-tolerant polymer microspheres with ultra-low interfacial tension by adopting inverse phase emulsion polymerization. The prepared polymer microsphere plugging agent is a new type of polymer microspheres with ultra-low interfacial tension, such that the tension can reach 4.3×10.sup.−3 mN/m, and the salt tolerance can reach 50000 mg/L salinity, which improves the problem of low interfacial tension and poor salt tolerance in existing polymer microspheres.

The present disclosure relates to spacer fluids for use in subterranean operations and, more particularly, in certain embodiments, to spacer fluids that include a spacer additive comprising a solid scouring material and a biopolymer gum while being essential free of clay. An example method may comprise spacer fluid comprise water and a spacer additive. The spacer additive may comprise a solid scouring material and a biopolymer gum, wherein the solid scouring material comprises crystalline silica in an amount of about 5 wt. % or less, and wherein the spacer fluid is essentially free of clay. The example method may further comprise and introducing the spacer fluid into a wellbore to displace at least a portion of a first fluid in the wellbore.

A mixture of at least two shapes of a dissolvable diverter material. The shapes range from a flake having a high surface area to mass ratio to beads having a low surface area to mass ratio. The density of the various shapes may be manipulated by including voids or low-density materials within the shape. The density manipulation allows matching the transport properties of the at least two shapes to the transport fluid so that both shapes may arrive at the desired location at the desired time.

A method includes providing an expandable metal slurry downhole in a wellbore. The expandable metal slurry includes granules of an expandable metal material suspended or dispersed in a fluid. Further, the method includes positioning the expandable metal slurry within the wellbore such that the granules of the expandable metal material in the expandable metal slurry are activatable to expand and form a seal within the wellbore.

Application of biodegradable oils to additive particles to control dusting. A method of reducing an amount of dust produced during transfer of additive particles comprising: treating at least some of the additive particles with one or more biodegradable oils; storing the additive particles; and transferring the additive particles prior to and after storage, wherein biodegradable oil reduces the amount of dust produced during at least one of the transfers of the additive particles.

Application of biodegradable oils to additive particles to control dusting. A method of reducing an amount of dust produced during transfer of additive particles comprising: treating at least some of the additive particles with one or more biodegradable oils; storing the additive particles; and transferring the additive particles prior to and after storage, wherein biodegradable oil reduces the amount of dust produced during at least one of the transfers of the additive particles.

A method of treating a well comprising introducing a well treatment fluid into the well, and a well treatment fluid, are provided. The well treatment fluid comprises an aqueous base fluid, sepiolite clay, and a polymer component selected from the group of an acryloylmorpholine polymer, a polyvinylpyrrolidone polymer, and mixtures thereof. In one embodiment, for example, the method is a method of drilling a well. In this embodiment, the well treatment fluid is a drilling fluid.

A microorganism curing anti-seepage device based on capsule transmission and control includes a stock bin which includes a mixing bin and an oil storage bin separated from the mixing bin. A feed pipe and an oil injection pipe are provided on the stock bin. A central shaft is rotatably provided within the mixing bin. A stirring component is provided on the central shaft. A delivery pipe is provided at a bottom portion of the mixing bin, an oil conduit is provided at a bottom portion of the oil storage bin, a jet pipe is provided at a junction of the oil conduit and the delivery pipe. Since microbial capsules are decomposed layer by layer, after the microbial capsules reach fissures, the microbial bacteria, the nutrient solution and the curing liquid are released step by step, and then calcium carbonate is induced by microorganisms to achieve solidification and anti-seepage of fissures.

Methods and compositions comprising an emulsion or a microemulsion for use treating an oil and/or gas well are provided. In some embodiments, the emulsion or the microemulsion comprises an aqueous phase, a solvent, a surfactant comprising alkyl polyglycoside, an alcohol, and, optionally, one or more additives.

Methods and compositions comprising an emulsion or a microemulsion for use treating an oil and/or gas well are provided. In some embodiments, the emulsion or the microemulsion comprises an aqueous phase, a solvent, a surfactant comprising alkyl polyglycoside, an alcohol, and, optionally, one or more additives.