Embodiments are directed to a lubricant package for water based drilling fluids. The lubricant package includes water, a polyethylene glycol, and a lubricating agent. The lubricating agent includes triethanolamine, or a C.sub.12-C.sub.14 alcohol ethoxylate, or a combination of triethanolamine and C.sub.12-C.sub.14 alcohol ethoxylate. The weight ratio of the polyethylene glycol to the lubricating agent in the lubricant package is from 1:2 to 2:1. Embodiments are also directed to a water-based drilling fluid composition including an aqueous base fluid, one or more additives, and the lubricant package for water based drilling fluids.

A system, method, and power control device for powering electronics located in a wellbore intersecting a subterranean earth formation. The system comprises a battery, a turbine generator, an electronic device, and a processor. The battery is locatable in the wellbore and the turbine generator is locatable in the wellbore so as to be in fluid communication with a flow path in the wellbore. The electronic device is locatable in the wellbore and electrically coupled to the battery and the turbine generator. The processor determines if a power condition is satisfied to allow the turbine generator to power the electronic device. The method comprises powering an electronic device located in the wellbore using a battery and opening a closed flow path in communication with a turbine generator. The method also comprises powering the electronic device using the turbine generator if a power condition is satisfied.

Treatment material for a wellbore operation can be mixed with a metal material coated with a layer that is controllably activated to release the metal material downhole in a wellbore. The wellbore treatment material can be mixed with the metal material prior to being positioned downhole in the wellbore.

A straddle packer for proppant-laden fracturing fluids has a slotted frac sub with a proppant filtration plug body that excludes proppant in the fracturing fluid from a central passage of the straddle packer downhole from the slotted frac hub. Pressure equalization sleeve filters exclude an entry of debris in a well bore through pressure equalization ports of the straddle packer.

A wellbore servicing fluid comprises an aqueous base fluid, one or more alkali metal or alkali earth metal salts, at least one visocisifier, and a filtration control package. The filtration control package may comprise a carboxylic acid and an ethoxylated alcohol compound. Alternatively, the filtration control package may comprise a polyethylene glycol. The carboxylic acid may have from 8 to 20 carbon atoms. The ethoxylated alcohol compound may have a general formula R—(OCH.sub.2CH.sub.2).sub.X—OH, where R is a hydrocarbon having from 10 to 16 atoms and x is an integer from 6 to 9. The ethoxylated alcohol compound may have a hydrophilic-lipophilic balance of from 8.0 to 16.0. The polyethylene glycol may have a mass average molar mass (M.sub.w) of less than or equal to 1500 daltons.

An example laser tool is configured to operate within a wellbore of a hydrocarbon-bearing rock formation. The laser tool includes one or more optical transmission media as part of an optical path originating at a laser generator configured to generate a laser beam having an axis. The laser tool includes an optical element for receiving the laser beam from the one or more optical transmission media and for output to the hydrocarbon-bearing rock formation. The laser tool includes a purging head for removing dust or vapor from a path of the laser beam. The purging head is for discharging two or more purging gas streams. The purging head may include a coaxial flow assembly and a helical flow assembly. A coaxial purging gas stream may flow in a direction parallel to the axis. A helical purging gas stream may flow in a helical pattern around and substantially along the axis.

An example CO.sub.2 monitoring systems is configured for monitoring levels of CO.sub.2 in a wellbore. A CO.sub.2 monitoring system may include one or more laser monitoring tools. A laser monitoring tool may include an optical element to output a laser beam, a detector to receive the laser beam, a first chamber housing the optical element and detector, and a second chamber including an inlet and an outlet receive and release, respectively, wellbore fluid. The first chamber may be in fluid connection with second chamber via a gas permeable membrane. Gas may permeate from second chamber into first chamber. Gas in the first chamber is subjected to a laser beam. Absorption of light by the gas is measured, and content of gas is determined based at least in part on the amount of light absorption by the gas.

A straddle packer for proppant-laden fracturing fluids has a slotted frac sub with a proppant filtration plug body that excludes proppant in the fracturing fluid from a central passage of the straddle packer downhole from the slotted frac hub. Pressure equalization sleeve filters exclude an entry of debris in a well bore through pressure equalization ports of the straddle packer.

A downhole mud filter (100) comprising a tubular member (1) connectable to the drill string used to prevent debris-laden fluid from entering sensitive BHA tools and components further downhole relative to the mud filter. A tubular member having a sub assembly consisting of a bristle rings (6) and/or rupture (7) to intentionally create a restriction and divert debris-laden fluid around a cylindrical mesh (2) and/or screen surrounded by permanent magnets (3). The openings (9) on the mesh and/or screen allow fluid to pass through while preventing particulates or debris from entering and retaining such debris on the outside of the screen and/or mesh. Magnets (3) arranged around the outer diameter of the screen and/or mesh (2) and along its length captures and retains smaller ferrous debris which the screen and/or mesh cannot filter.

Cement slurries, cured cements, and methods of making cured cement and methods of using cement slurries are provided. The cement slurry contains water, a cement precursor material, an alcohol surfactant having from 10 to 20 carbon atoms and a carboxylic acid comprising an aliphatic chain having from 16 to 18 carbons. In some embodiments, the alcohol surfactant may comprise the formula R—(OC.sub.2H.sub.4).sub.x—OH where R is a hydrocarbyl group having from 10 to 20 carbons and x is an integer from 1 to 10. The cured cement contains water, cement, an alcohol surfactant having from 10 to 20 carbon atoms and a carboxylic acid comprising an aliphatic chain having from 16 to 18 carbons. In some embodiments, the alcohol surfactant may comprise the formula R—(OC.sub.2H.sub.4).sub.x—OH where R is a hydrocarbyl group having from 10 to 20 carbons and x is an integer from 1 to 10.