A method may include: providing a cleanout fluid comprising a single anionic surfactant, a single nonionic surfactant, and a solvent; preparing a cleanout pill by mixing the cleanout fluid with a brine; and displacing a fluid in a wellbore using the cleanout pill.

A method may include: providing a cleanout fluid comprising a single anionic surfactant, a single nonionic surfactant, and a solvent; preparing a cleanout pill by mixing the cleanout fluid with a brine; and displacing a fluid in a wellbore using the cleanout pill.

A method is provided for inhibiting formation of a gas hydrate in a pipeline or removing a gas hydrate existing in a pipeline. The method can comprise injecting a foam composition into a fluid in the pipeline to inhibit formation of the gas hydrate in the pipeline, prevent gas hydrate formation in the pipeline, or remove the gas hydrate from the pipeline.

A method is provided for inhibiting formation of a gas hydrate in a pipeline or removing a gas hydrate existing in a pipeline. The method can comprise injecting a foam composition into a fluid in the pipeline to inhibit formation of the gas hydrate in the pipeline, prevent gas hydrate formation in the pipeline, or remove the gas hydrate from the pipeline.

A brine-based viscosified pill including (1) a viscosified brine, (2) a surfactant-solvent blend containing about 5 wt. % to about 40 wt. % of at least one nonionic surfactant; about 5 wt. % to about 20 wt. % of at least one polyglycerol ester, about 20 wt. % to about 60 wt. % of at least one co-solvent; about 20 wt. % to about 25 wt. % water; and optionally about 1 wt. % to about 15 wt. % of at least one hydrophobic solvent, and (3) no solid weighting agent, may be introduced to a wellbore in an effective amount to clean the wellbore or displace fluid in the wellbore at a wide range of temperatures.

A brine-based viscosified pill including (1) a viscosified brine, (2) a surfactant-solvent blend containing about 5 wt. % to about 40 wt. % of at least one nonionic surfactant; about 5 wt. % to about 20 wt. % of at least one polyglycerol ester, about 20 wt. % to about 60 wt. % of at least one co-solvent; about 20 wt. % to about 25 wt. % water; and optionally about 1 wt. % to about 15 wt. % of at least one hydrophobic solvent, and (3) no solid weighting agent, may be introduced to a wellbore in an effective amount to clean the wellbore or displace fluid in the wellbore at a wide range of temperatures.

Release of hydrochloric acid, hydrofluoric acid and fluoroboric acid into a well may be controlled by introducing into the well an aqueous fluid containing ammonium chloride, ammonium bifluoride, ammonium fluoroborate, ammonium tetrafluoroborate or a mixture thereof and a breaker. After being introduced into the well, the ammonium salt reacts with the breaker and the acid is released into the well.

In a well in a subterranean formation, treatment fluids for time-released iron control are utilized. These treatment fluids contain a time-released form of a complexing agent, wherein the complexing agent forms an insoluble complex with iron. The time-released form prevents loss of the agent prior to delivery to the desired site and at the desired time(s). Methods for controlling iron in a well in a subterranean formation utilize these treatment fluids containing a time-released form of a complexing agent and these methods create insoluble complexes of the agent with the iron to control the iron from the formation and/or well.

In a well in a subterranean formation, treatment fluids for time-released iron control are utilized. These treatment fluids contain a time-released form of a complexing agent or reducing agent, wherein the agent forms a soluble product with iron. The time-released form prevents loss of the agent prior to delivery to the desired site and at the desired time(s). Methods for controlling iron in a well in a subterranean formation utilize these treatment fluids containing a time-released form of a complexing agent or reducing agent and these methods create soluble products when the agent interacts with the iron to control the iron from the formation and/or well.

A gravel pack containing a substrate particle coated with an inducibly degradable and a porous particle having an internal interconnected porosity that is at least partially infused with an inducer material for dissolving of a layer of filter cake disposed between the gravel pack and a subterranean formation.