Degradable fibers for water savings in hydraulic fracturing
Systems and methods presented herein generally relate to introducing degradable fibers into a clean fluid having no proppants contained therein to produce a fiber-containing fluid, and injecting the fiber-containing fluid into a wellbore extending through a subterranean formation during a pad stage of a hydraulic fracturing operation. In general, the systems and methods presented herein block fluid leak-off flow through walls of fractures created during hydraulic fracturing operations.
1 . A method, comprising:
introducing fibers into a clean fluid having no proppants contained therein to produce a fiber-containing fluid;
injecting the fiber-containing fluid into a wellbore extending through a subterranean formation during a pad stage of a hydraulic fracturing operation, wherein the fibers are configured to form a fiber filter cake along walls of fractures extending from the wellbore into the subterranean formation;
detecting, using one or more sensors, one or more operating parameters of the hydraulic fracturing operation in substantially real-time during the hydraulic fracturing operation; and
using a fiber feeder to adjust at least one of a type of the fibers used or a concentration of the fibers to be added to the clean fluid during the pad stage based at least in part on the one or more operating parameters of the hydraulic fracturing operation in substantially real-time during the hydraulic fracturing operation to control a leak-off rate through the walls of the fractures.
2 . The method of claim 1 , wherein the fiber-containing fluid comprises a concentration of the fibers in the clean fluid of 1 pound mass to 50 pound mass per 1000 US gallons.
3 . The method of claim 1 , wherein each fiber of the fibers has a length of 0.5 millimeters to 30 millimeters.
4 . The method of claim 1 , wherein each fiber of the fibers has a thickness of 5 microns to 50 microns.
5 . The method of claim 1 , wherein each fiber of the fibers consists essentially of polylactic acid.
6 . The method of claim 1 , wherein the fibers are selected from the group consisting of substituted and unsubstituted lactide, glycolide, polylactic acid, polyglycolic acid, copolymers of polylactic acid and polyglycolic acid, copolymers of glycolic acid with other hydroxy-, carboxylic acid-, or hydroxycarboxylic acid-containing moieties, copolymers of lactic acid with other hydroxy-, carboxylic acid-, or hydroxycarboxylic acid-containing moieties, and mixtures thereof.
7 . The method of claim 1 , wherein the fiber filter cake reduces fluid leak-off through the walls of the fractures.
8 . The method of claim 1 , wherein the fibers are configured to degrade over time after forming the fiber filter cake along the walls of the fractures.
9 . The method of claim 1 , wherein the one or more operating parameters of the hydraulic fracturing operation comprise fluid viscosity, presence of fissures in rock of the subterranean formation, transmissibility of the rock of the subterranean formation, permeability of the rock of the subterranean formation, or any combination thereof.
10 . A method, comprising:
introducing degradable polylactic acid (PLA) fibers into a clean fluid having no proppants contained therein to produce a fiber-containing fluid, wherein the fiber-containing fluid comprises a concentration of the degradable PLA fibers in the clean fluid of 1 pound mass to 50 pound mass per 1000 US gallons, wherein each degradable PLA fiber of the degradable PLA fibers has a length of 0.5 millimeters to 30 millimeters, and wherein each degradable PLA fiber of the degradable PLA fibers has a thickness of 5 microns to 50 microns;
injecting the fiber-containing fluid into a wellbore extending through a subterranean formation during a pad stage of a hydraulic fracturing operation, wherein the degradable PLA fibers are configured to form a fiber filter cake along walls of fractures extending from the wellbore into the subterranean formation;
detecting, using one or more sensors, one or more operating parameters of the hydraulic fracturing operation in substantially real-time during the hydraulic fracturing operation; and
using a fiber feeder to adjust at least one of a type of the degradable PLA fibers used or a concentration of the degradable PLA fibers to be added to the clean fluid during the pad stage based at least in part on the one or more operating parameters of the hydraulic fracturing operation in substantially real-time during the hydraulic fracturing operation to control a leak-off rate through the walls of the fractures.
11 . The method of claim 10 , wherein the one or more operating parameters of the hydraulic fracturing operation comprise fluid viscosity, presence of fissures in rock of the subterranean formation, transmissibility of the rock of the subterranean formation, permeability of the rock of the subterranean formation, or any combination thereof.
12 . The method of claim 10 , wherein the fiber filter cake reduces fluid leak-off through the walls of the fractures.
13 . The method of claim 10 , wherein:
the one or more operating parameters of the hydraulic fracturing operation comprise fluid viscosity, presence of fissures in rock of the subterranean formation, transmissibility of the rock of the subterranean formation, permeability of the rock of the subterranean formation, or any combination thereof,
the one or more sensors comprise surface sensors and downhole sensors,
the fiber feeder comprises a fiber hopper, a screw auger, and a fiber discharge to introduce the degradable PLA fibers into the clean fluid, and
the fiber filter cake reduces fluid leak-off through the walls of the fractures by reducing a leak-off coefficient by 15% to 18%.
14 . A fiber feeder configured to:
introduce fibers into a clean fluid having no proppants contained therein to produce a fiber-containing fluid;
provide the fiber-containing fluid to a pump to enable pumping of the fiber-containing fluid into a wellbore extending through a subterranean formation during a pad stage of a hydraulic fracturing operation, wherein the fibers are configured to form a fiber filter cake along walls of fractures extending from the wellbore into the subterranean formation;
receive, from one or more sensors, one or more operating parameters of the hydraulic fracturing operation in substantially real-time during the hydraulic fracturing operation; and
adjust one or more properties of at least one of the fibers or the clean fluid based at least in part on the one or more operating parameters of the hydraulic fracturing operation in substantially real-time during the hydraulic fracturing operation to control a leak-off rate through the walls of the fractures.
15 . The fiber feeder of claim 14 , wherein the one or more operating parameters of the hydraulic fracturing operation comprise fluid viscosity, presence of fissures in rock of the subterranean formation, transmissibility of the rock of the subterranean formation, permeability of the rock of the subterranean formation, or some combination thereof.