# US 10,870,795 B2 · Rheology modifier > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,870,795 B2 - Document ID: US10870795B2 - Status: Granted - Kind: B2 - Application number: 15/749,027 - Filed: 2015-10-15 - Published: 2019-01-03 - Granted: 2020-12-22 - Earliest claimed: 2015-10-15 - Assignees: Halliburton Energy Services, Inc. - Applicants: Halliburton Energy Services, Inc. - Inventors: Janette Cortez; Dipti Singh; Ubong Inyang - Web page: https://patentgrep.com/patent/US10870795B2 ## CPC - C09K 8/887: {containing cross-linking agents} - C09K 8/512: containing cross-linking agents - C09K 8/514: of natural origin, e.g. polysaccharides, cellulose (C09K8/512 takes precedence) - C09K 8/516: characterised by their form or by the form of their components, e.g. encapsulated material - C09K 8/90: of natural origin, e.g. polysaccharides, cellulose - C09K 8/92: characterised by their form or by the form of their components, e.g. encapsulated material (C09K8/70 takes precedence) - C09K 2208/24: Bacteria or enzyme containing gel breakers - C09K 2208/26: Gel breakers other than bacteria or enzymes - C09K: MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE ## Abstract The composition provided herein includes an aqueous base fluid, a water-based polymer and glass microspheres comprising a metal cross-linking agent and where the water-based polymer cross-links in the presence of the glass microspheres. ## Claims ### Claim 1 A composition comprising: an aqueous base fluid; a water-based polymer present in an amount from about 5 lb to about 100 lbs per 1000 gallons of the aqueous base fluid; salt present in the amount of about 1% (w/v) to about 20% (w/v) of the total volume of the aqueous base fluid; and glass microspheres comprising a metal cross-linking agent, wherein the glass microspheres are between about 5 to about 500 microns, the metal cross-linking agent comprises from about 8% to about 25% of the glass microsphere's chemical composition, and the glass microspheres are present in the amount of from about 0.5% (w/v) to about 15% (w/v) based on the total volume of the aqueous base fluid; and wherein the water-based polymer cross-links in the presence of the glass microspheres and the presence of salt increases the viscosity of the composition by at least 50 cP over the viscosity of the composition in the absence of salt. ### Claim 2 (depends on 1) The composition of claim 1, wherein the composition is essentially free of any cross-linking agent other than the glass microspheres. ### Claim 3 (depends on 1) The composition of claim 1, wherein the glass microspheres are uncoated. ### Claim 4 (depends on 1) The composition of claim 1, wherein the water-based polymer only cross-links with surfaces of the glass microspheres. ### Claim 5 (depends on 1) The composition of claim 1, wherein the salt is present in the amount of about 4% (w/v) to about 5% (w/v) of the aqueous base fluid. ### Claim 6 (depends on 1) The composition of claim 1, wherein the glass microspheres are present in the amount of about 2% (w/v) to about 13% (w/v) based on the total volume of the aqueous base fluid. ### Claim 7 (depends on 1) The composition of claim 1, wherein the glass microspheres are present in the amount of at least about 3% (w/v) based on the total volume of the aqueous base fluid. ### Claim 8 (depends on 1) The composition of claim 1, wherein the glass microspheres are present in the amount of at least about 4% (w/v) based on the total volume of the aqueous base fluid. ### Claim 9 (depends on 1) The composition of claim 1, wherein crosslinks formed during the cross-linking of the water-based polymer in the presence of the glass microspheres are transient and self-degrade in about 1 to about 10 days. ### Claim 10 (depends on 1) The composition of claim 1, wherein the water-based polymer is carboxymethylhydroxyethylcellulose (CMHEC) present in the amount of about 25 lbs to about 50 lbs per about 1000 gallons of the aqueous base fluid. ### Claim 11 (depends on 1) The composition of claim 1, wherein the metal cross-linking agent comprises at least one of a boron compound, a zirconium compound, a titanium compound, an aluminum compound, an antimony compound, a chromium compound, an iron compound, a copper compound, a zinc compound, or a combination thereof. ### Claim 12 (depends on 11) The composition of claim 11, wherein the metal cross-linking agent is an aluminum compound constituting from about 9% to about 16% of the glass microspheres' chemical composition. ### Claim 13 (depends on 12) The composition of claim 12, wherein the water-based polymer comprises at least one of hydropropyl guar (HPG), carboxymethyl guar (CMG), carboxymethylhydropropyl guar (CMHPG), hydroxyethylated guar (HEG), hydroxyethylcellulose (HEC), hydroxypropylcellulose (HPC), carboxymethyl cellulose (CMC) and carboxymethylhydroxyethylcellulose (CMHEC), or a combination thereof. ### Claim 14 A method comprising the steps of: (a) providing a composition comprising an aqueous base fluid, glass microspheres comprising a metal cross-linking agent, and a water-based polymer, wherein the water-based polymer is present in an amount of from about 5 lb to about 100 lbs per 1000 gallons of the aqueous base fluid, wherein the glass microspheres are between 5 to about 500 microns and the metal cross-linking agent comprises from about 8% to about 25% of the glass microsphere's chemical composition; and (b) creating a gelled fluid by cross-linking the water-based polymer in the presence of from about 0.5% (w/v) to about 15% (w/v) of the glass microspheres based on the total volume of the aqueous base fluid, and in the presence of about 1% (w/v) to about 20% (w/v of a salt based on the total volume of the aqueous base fluid, such that metal ions present in the glass microspheres act as a cross-linking agent and the presence of salt increases the viscosity of the composition by at least 50 cP over the viscosity of the composition in the absence of salt. ### Claim 15 (depends on 14) The method of claim 14, wherein the glass microspheres are uncoated. ### Claim 16 (depends on 14) The method of claim 14, wherein cross-links in the gelled fluid only form by a process consisting essentially of cross-linking the polymer by the metal ions present in the glass microspheres. ### Claim 17 (depends on 14) The method of claim 14, wherein the metal cross-linking agent is a boron compound constituting from about 9% to about 16% of the glass microspheres chemical composition. ### Claim 18 (depends on 14) The method of claim 14, wherein the water-based polymer is hydrated prior to the addition of the glass microspheres. ### Claim 19 (depends on 14) The method of claim 14, wherein the glass microspheres are present in the aqueous base fluid before being added to the water-based polymer. ### Claim 20 (depends on 14) The method of claim 14, further comprising using a blender system to mix the aqueous base fluid, the glass microspheres and the water-based polymer; and using a pump to place the composition in a subterranean formation.