# US 2013/0153232 A1 · Methods and compositions for reducing permeability of a subterranean formation > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2013/0153232 A1 - Document ID: US20130153232A1 - Status: Published application - Kind: A1 - Application number: 13/710,959 - Filed: 2012-12-11 - Published: 2013-06-20 - Earliest claimed: 2011-12-15 - Assignees: Calfrac Well Services Ltd. - Inventors: Dwight Bobier; Ronald Pierce - Web page: https://patentgrep.com/patent/US20130153232A1 ## CPC - E21B 43/12: Methods or apparatus for controlling the flow of the obtained fluid to or in wells (E21B43/25 takes precedence; valve arrangements E21B34/00) - C09K 8/06: Clay-free compositions (containing inorganic compounds only C09K8/05) - C09K 8/5045: {containing inorganic compounds} - C09K 8/506: containing organic compounds - E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS - C09K: MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE ## Abstract The present application is directed to an aqueous composition made up of an alkali metal silicate; a hardener containing at least one dibasic ester, at least one nonionic surfactant, at least one terpene or terpene derivative and optionally at least one polyalkylene glycol; and a retarder. The composition is useful for reducing the permeability in a subterranean formation, so as to reduce or prevent water flow and circulation loss of well fluids such as drilling fluids or cement. ## Claims ### Claim 1 An aqueous composition for reducing the permeability of a subterranean formation by formation of a silica gel; the composition comprising: an alkali metal silicate; a hardener comprising at least one dibasic ester, at least one non-ionic surfactant, at least one terpene or terpene derivative and optionally at least one polyalkylene glycol; a retarder; and water. ### Claim 2 (depends on 1) The composition according to claim 1 comprising about 25% to about 60% by volume of the alkali metal silicate; about 5% to about 15% by volume of the hardener; about 0.1% to about 1.5% by volume of the retarder; and about 25% to about 60% water by volume. ### Claim 3 (depends on 1) The composition according to claim 1 wherein the alkali metal silicate is sodium silicate. ### Claim 4 (depends on 1) The composition according to claim 1 wherein the at least one dibasic ester is selected from a di(C1-6)alkyl ethylsuccinate, a di(C1-6)alkyl methylglutarate, a di(C1-6)alkyl adipate, and a mixture thereof. ### Claim 5 (depends on 4) The composition according to claim 4 wherein the at least one dibasic ester is dimethyl 2-methylglutarate. ### Claim 6 (depends on 1) The composition according to claim 1 wherein the at least one non-ionic surfactant is at least one aliphatic alkoxylated alcohol. ### Claim 7 (depends on 6) The composition according to claim 6 wherein the at least one aliphatic alkoxylated alcohol is ethoxylated isodecyl alcohol having a Hydrophile-Lipophile Balance (HLB) number between about 7 and about 15. ### Claim 8 (depends on 1) The composition according to claim 1 wherein the at least one terpene or terpene derivative is selected from pinene and limonene. ### Claim 9 (depends on 1) The composition according to claim 1 wherein the at least one terpene or terpene derivative is an ethoxyl propoxyl terpene. ### Claim 10 (depends on 1) The composition according to claim 1 wherein the at least one polyalkylene glycol is polyethylene glycol. ### Claim 11 (depends on 1) The composition according to claim 1 wherein the hardener comprises about 30% to about 60% by weight of an aliphatic ethoxylated alcohol; about 30% to about 60% by weight of dimethyl 2-methylglutarate; about 5% to about 10% by weight of an ethoxyl propoxyl terpene; and no more than 5% by weight polyethylene glycol. ### Claim 12 (depends on 1) The composition according to claim 1 wherein the retarder is selected from borax, boric acid, alkaline earth metal hydroxides and alkaline earth metal carbonates. ### Claim 13 (depends on 1) The composition according to claim 1 further comprising a pozzolanic material. ### Claim 14 (depends on 13) The composition according to claim 13 wherein the pozzolanic material is selected from fly ash, silica fume, metakaolin, and ground granulated blast furnace slag. ### Claim 15 (depends on 1) The composition according to claim 1 further comprising a lost circulation material. ### Claim 16 (depends on 15) The composition according to claim 15 wherein the lost circulation material is selected from silica, rubber crumbs, insoluble fibers and cellophane flakes. ### Claim 17 (depends on 1) A method of reducing or preventing water flow in a subterranean formation, comprising injecting a composition according to claim 1 into the matrix of the subterranean formation. ### Claim 18 (depends on 1) A method of reducing or preventing lost circulation in a subterranean formation, comprising injecting a composition according to claim 1 into the matrix of the subterranean formation. ### Claim 19 (depends on 17) The method according to claim 17 wherein the subterranean formation is a hydrocarbon-producing formation. ### Claim 20 (depends on 18) The method according to claim 18 wherein the subterranean formation is a hydrocarbon-producing formation.