Compositions And Methods For Servicing Subterranean Wells

Abstract

This invention relates to methods for servicing subterranean wells, in particular, fluid compositions and methods for remedial operations during which the fluid compositions are pumped into a wellbore and make contact with well cements placed during primary cementing or previous remedial cementing operations.

We claim: 
     
         1 . A pumpable sealant composition for repairing voids or fractures in, or adjacent to, a set cement sheath in a subterranean well, comprising an aqueous slurry of aluminosilicate particles, aluminum compound/silica particle blends, aluminium compound/silicate particle blends, or combinations thereof, wherein the slurry has no cementitious properties in and of itself, wherein the aluminosilicate particles are one or more members selected from the group consisting of kaolin, metakaolin, Class F fly ash, blast furnace slag and zeolites. 
     
     
         2 . (canceled) 
     
     
         3 . The composition of  claim 1 , wherein the subterranean well has been cemented with Portland cement, a lime/silica blend, a lime/pozzolan blend, calcium aluminate cement, chemically bonded phosphate ceramic, or combinations thereof. 
     
     
         4 . The composition of  claim 1 , wherein the average size of the particles is less than or equal to 15 micrometers. 
     
     
         5 . The composition of  claim 1 , further comprising one or more weighting materials chosen from the list comprising: ilmenite, hematite, barite and manganese tetraoxide. 
     
     
         6 . The composition of  claim 1 , further comprising sodium hexametaphosphate. 
     
     
         7 . The composition of  claim 1 , further comprising a latex. 
     
     
         8 . The composition of  claim 1 , further comprising soluble silicate compounds. 
     
     
         9 . The composition of  claim 1 , further comprising hydroxide compounds. 
     
     
         10 . The composition of  claim 1 , further comprising alkali swellable polymers, superabsorbent polymers, or both. 
     
     
         11 . The composition of  claim 10 , wherein the alkali swellable polymers are latexes. 
     
     
         12 - 20 . (canceled)