Abstract: A method for decontaminating a liquid having sulfides includes preparing a stabilized sodium percarbonate solution. In an embodiment, the method includes decontaminating a liquid. The liquid comprises reactive sulfides. The method also includes preparing a stabilized sodium percarbonate solution, which includes adding sodium percarbonate to a liquid solution. The liquid solution comprises a peroxide stabilizer and an acid. The method further includes dosing the liquid into the stabilized sodium percarbonate solution to decontaminate the liquid by oxidizing at least a portion of the reactive sulfides.

Abstract: A system and method treat oilfield produced water by two-stages of hazardous sulfide treatments. In an embodiment, a two-stage oil and gas field produced water treatment system includes an oil removal vessel. The oilfield produced water is introduced to the oil removal vessel. The oil removal vessel removes a portion of the hydrocarbons from the oilfield produced water to provide a reduced oil produced water. In addition, the system includes an iron sponge. The reduced oil produced water is introduced to the iron sponge, and the iron sponge removes a portion of the hazardous sulfides from the reduced oil produced water to provide a reduced sulfide produced water. The system also includes a stabilized sodium percarbonate solution. The stabilized sodium percarbonate solution is mixed with the reduced sulfide produced water to remove a portion of the hazardous sulfides from the reduced sulfide produced water to provide a treated produced water.

Abstract: The concentration of unspent zinc-based hydrogen sulfide scavenger in an aqueous drilling fluid is controlled by selectively extracting the unspent scavenger in a solvent, such as glacial acetic acid, measuring the concentration of dissolved zinc, for example, with an X-ray fluorescence spectrograph, and utilizing the results of the measurements to proportion the extent of changes to be made in the concentration of the scavenger.

Abstract: The concentration of unspent zinc-based hydrogen sulfide scavenger in an oil-based drilling fluid is controlled by selectively dissolving and extracting the unspent scavenger in a solvent, such as glacial acetic acid, separating the aqueous solution, measuring the concentration of dissolved zinc in the aqueous solution, for example, with an X-ray fluorescence spectrograph, and utilizing the results of the measurements to proportion the extent of changes in concentration of the scavenger in the drilling fluid.

Abstract: The concentration of unspent zinc-based hydrogen sulfide scavenger in an aqueous drilling fluid is controlled by selectively extracting an unspent scavenger in a solvent, such as glacial acetic acid, measuring the concentration of dissolved zinc, for example, with an X-ray fluorescence spectrograph, and utilizing the results of the measurements to proportion the extent of changes to be made in the concentration of the scavenger.

Abstract: The concentration of unspent zinc-based hydrogen sulfide scavenger in an aqueous drilling fluid is controlled by selectively extracting the unspent scavenger in a solvent, such as glacial acetic acid, measuring the concentration of dissolved zinc, for example, with an X-ray fluorescence spectrograph, and utilizing the results of the measurements to proportion the extent of changes to be made in the concentration of the scavenger.