Method for generating self-propped hydraulic fractures
AssigneeQuidnet Energy Inc.
InventorsHoward Schmidt, Scott Wright, Bunker Hill, Henry Lau
Life of this patent
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Abstract
A method for generating self-propped hydraulic fractures. In one embodiment, the method comprises injecting three fluid stages sequentially, each with successively higher viscosity, comprising a pad, a sealing slurry, and a displacement fluid which may be referred to as a sweep. Compositions of each of the three fluid stages are provided, each of which may be selected based upon characteristics of the formation being treated or upon one or more characteristics of the desired fracture.
Claims15
A method of generating a self-propped hydraulic fracture, comprising:
- injecting a first fluid into a wellbore, wherein the first fluid comprises 27 pounds-per-barrel (ppb) bentonite mud and has a viscosity from one to one thousand centipoise;
- injecting a second fluid into the wellbore, wherein the second fluid comprises up to 2 mm rubber tire crumb (RTC) in 25 ppb cross-linked guar with 4 ppb mineral fiber;
- and has a viscosity from ten to five thousand centipoise and is loaded between 5% and 30% by weight with particles
- injecting a spacer fluid, wherein the spacer fluid comprises a 2% partially hydrolyzed poly acrylamide (PHPA);
- and
- injecting a third fluid into the wellbore, wherein the third fluid comprises a 35 ppt cross-linked guar with enzymatic breaker and has a viscosity of one hundred to one million centipoise;
- wherein the first fluid is 15% of the total volume of the injected fluids, the second fluid is 30% of the total volume of the injected fluids, the spacer fluid is 4% of the total volume of the injected fluids, and the third fluid is 51% of the total volume of the injected fluids;
- and wherein the first fluid, the second fluid, and the third fluid are injected such that each successive injection fluid has a viscosity equal to or greater than the viscosity of the preceding fluid.
A method of generating a self-propped hydraulic fracture, comprising:
- injecting a first fluid into a wellbore, wherein the first fluid has a viscosity from one to one thousand centipoise;
- injecting a second fluid into the wellbore, wherein the second fluid comprises H class cement and has a viscosity from ten to five thousand centipoise and is loaded between 5% and 30% by weight with particles;
- and
- injecting a third fluid into the wellbore, wherein the third fluid comprises 35 ppt cross-linked guar with enzymatic breaker and has a viscosity of one hundred to one million centipoise;
- wherein the first fluid is 20% of the total volume of the three fluids, the second fluid is 40% of the total volume of the three fluids, and the third fluid is 40% of the total volume of the three fluids, wherein the first fluid, the second fluid, and the third fluid are injected such that each successive injection fluid has a viscosity equal to or greater than the viscosity of the preceding fluid.
A method of generating a self-propped hydraulic fracture, comprising:
- injecting a first fluid into a wellbore, wherein the first fluid comprises 1% PHPA gel and has a viscosity from one to one thousand centipoise;
- injecting a second fluid into the wellbore, wherein the second fluid comprises buffered metal ion cross-linked 1% PHPA loaded with RTC mixture up to 2 mm and begins as a fluid with viscosity from ten to five thousand centipoise but becomes more viscous, or even solid, over time;
- and is loaded between 5%-30% by weight with particles;
- and
- injecting a third fluid into the wellbore, wherein the third fluid comprises 35 ppt cross-linked guar with enzymatic breaker and has a viscosity of one hundred to one million centipoise;
- wherein the first fluid is 2% of the total volume of the three fluids, the second fluid is 16% of the total volume of the three fluids, and the third fluid is 82% of the total volume of the three fluids;
- wherein the first fluid, the second fluid, and the third fluid are injected such that each successive injection fluid has a viscosity equal to or greater than the viscosity of the preceding fluid.
Dependencies are inferred from the claim text.