ALEXANDRIA, Va., June 16 -- United States Patent no. 12,305,115, issued on May 20, was assigned to SCHLUMBERGER TECHNOLOGY Corp. (Sugar Land, Texas).
"Spacer fluids containing swellable abrasive particles" was invented by Dominic Vincent Perroni (Houston) and Anatoly Vladimirovich Medvedev (Sugar Land, Texas).
According to the abstract* released by the U.S. Patent & Trademark Office: "Spacer fluids or chemical washes are prepared that comprise water, a hydraulic cement and particles of an oil-absorbent material. The particles are present in an amount sufficient to alter a property of a non-aqueous drilling fluid. The spacer fluid or chemical wash is placed in a subterranean well, whereupon the spacer fluid or chemical wash contacts residu...