Process For Dissolving Deposits Comprising Alkaline Earth Metal Sulfates

摘要

A process for dissolving deposits comprising alkaline earth metal sulfates in underground installations or installation parts for production of mineral oil, natural gas and/or water, by treating the deposits with an aqueous formulation comprising methanesulfonic acid.

主权项

1. A process for dissolving deposits comprising alkaline earth metal sulfates in underground installations or installation parts for production of mineral oil and/or natural gas and/or water from underground formations, which comprises:
injecting an aqueous formulation for dissolution of the deposits into the underground installations, and allowing it to act on the deposits, wherein the aqueous formulation comprises:
(I) 15% by weight to 98.98% by weight of water,(II) 1% by weight to 75% by weight of methanesulfonic acid,(III) 0.01% by weight to 5% by weight of at least one water-miscible organic solvent, and(IV) 0.01% by weight to 5% by weight of at least one corrosion inhibitor, where the pH of the formulation used is ≦2.5 and the sum of components (I), (II), (III) and (IV) is at least 80% by weight based on the sum of all constituents.