摘要 |
A lost-circulation-material includes: rubber particulates; crosslinked-copolymer particulates; cellulosic particulates; an expandable clay; a hydrogel material, and optionally a thickener. The average size of the particulates is selected so that each of the rubber particulates, crosslinked-copolymer particulates, and cellulosic particulates differ by at least a factor of 2 in diameter from one another. The components are admixed with fresh water having low salinity to form a remedial plug. In one embodiment, the copolymer particulates are pre-formed beads; the rubber particulates are finely ground butyl rubber compound; the expandable clay includes smectite; the hydrogel includes a partially hydrolyzed polyacrylamide compound; and the cellulosic particulates are wood flour. Methods of forming a slurry for plugging lost-circulation zones, and methods of treating wellbores with the slurry, are described.
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