Abstract: The invention discloses a method comprising providing a fluid comprising a viscosifying agent in an aqueous medium; contacting the fluid with a halogenisocyanuric acid or halogenisocyanurate component; whereby the viscosity of the fluid with the halogenisocyanuric acid or halogenisocyanurate component is reduced compared to the viscosity of the fluid alone; and introducing the fluid into a well. The halogenisocyanuric acid component can be mono chloroisocyanuric acid, dichloroisocyanuric acid or trichloroisocyanuric acid. The halogenisocyanurate component can be an alkali metal monochloroisocyanurate, alkali metal dichloroisocyanurate or alkali metal trichloroisocyanurate.

Abstract: The invention discloses a method comprising providing a fluid comprising a viscosifying agent in an aqueous medium; contacting the fluid with a N-halogenated derivative of hydantoin; whereby the viscosity of the fluid with the N-halogenated derivative of hydantoin is reduced compared to the viscosity of the fluid alone; and introducing the fluid into a well. The N-halogenated derivative of hydantoin can be dichlorodimethylhydantoin (DCDMH), bromochlorodimethylhydantoin (BCDMH), or dibromodimethylhydantoin (DBDMH). The N-halogenated derivative of hydantoin can be 1,3-Dichloro-5,5-dimethylhydantoin or 1,3-Dibromo-5,5-dimethylhydantoin.

Abstract: The invention discloses a method comprising providing a fluid comprising a viscosifying agent in an aqueous medium; contacting the fluid with a halogenisocyanuric acid or halogenisocyanurate component; whereby the viscosity of the fluid with the halogenisocyanuric acid or halogenisocyanurate component is reduced compared to the viscosity of the fluid alone; and introducing the fluid into a well. The halogenisocyanuric acid component can be mono chloroisocyanuric acid, dichloroisocyanuric acid or trichloroisocyanuric acid. The halogenisocyanurate component can be an alkali metal monochloroisocyanurate, alkali metal dichloroisocyanurate or alkali metal trichloroisocyanurate.

Abstract: Methods and apparatus of embodiments of the invention relate to a system for treating a subterranean formation including mixing equipment to form a fluid comprising sodium hypochlorite and sodium diacetate; and pumps and a tubular to introduce the fluid into the subterranean formation, wherein a surface of the subterranean formation contains at least 15 percent less microorganisms than if no sodium hypochlorite were in the fluid. Methods and apparatus of embodiments of the invention relate to a method of producing a petroleum product from a wellbore including using a well treatment system comprising mixing equipment, pumps, and a tubular, forming a fluid comprising sodium hypochlorite and sodium diacetate; and introducing the fluid to the well treatment system to achieve a reduced population of microorganisms in the system.