Methods for performing refracturing operations using coke proppant particles
A method for performing a refracturing operation using coke proppant particles comprises refracturing a subterranean formation that has been previously hydraulically fractured with respect to a hydrocarbon well by injecting a fracturing fluid comprising a carrier fluid and coke proppant particles into the subterranean formation via a wellbore of the hydrocarbon well.
1 . A method, comprising:
(I) providing a subterranean formation that has been previously hydraulically fractured and produced a fluid through a completed well comprising a wellbore; and
(II) after step (I), injecting, via the wellbore, a fracturing fluid comprising a carrier fluid and coke proppant particles into the subterranean formation to restimulate the subterranean formation.
2 . The method of claim 1 , wherein the coke proppant particles are present in the fracturing fluid at a concentration from 14 kilograms per cubic meter to 480 kilograms per cubic meter, based on the volume of the carrier fluid.
3 . The method of claim 1 , wherein the coke proppant particles are present in the fracturing fluid at a concentration from 18 kilograms per cubic meter to 120 kilograms per cubic meter, based on the volume of the carrier fluid.
4 . The method of claim 1 , wherein the coke proppant particles are present in the fracturing fluid at a concentration from 23 kilograms per cubic meter to 96 kilograms per cubic meter, based on the volume of the carrier.
5 . The method of claim 1 , further comprising, after step (II):
(III) producing a product fluid from the subterranean formation via the wellbore.
6 . The method of claim 5 , wherein the product fluid comprises hydrocarbons.
7 . The method of claim 1 , wherein step (II) comprises injecting the fracturing fluid into pre-existing fractures in the subterranean formation.
8 . The method of claim 7 , wherein step (II) comprises at least one of:
extending at least one dimension of at least one of the pre-existing fractures; and
reopening at least one of the pre-existing hydraulic fractures that has at least partially closed before step (II).
9 . The method of claim 1 , wherein step (II) is performed via a bullhead refracturing method.
10 . The method of claim 1 , wherein step (II) comprises:
(II.1) creating new perforations in at least a portion of the wellbore; and
(II.2) injecting the fracturing fluid through the new perforations into the subterranean formation.
11 . The method of claim 10 , wherein in step (II.1), the new perforations are created through a pre-existing production casing string of the wellbore without installing a new casing string inside the pre-existing production casing string.
12 . The method of claim 10 , wherein step (II.1) comprises:
(II. 1.1) installing a new production casing string in a pre-existing casing string of the wellbore to isolate pre-existing perforations in a pre-existing production casing string of the wellbore; and
(II. 1.2) creating new perforations through the new production casing string and the pre-existing casing string.
13 . The method of claim 12 , wherein in step (II.2), a stage length during a hydraulic fracturing operation is larger than a stage length during a previous hydraulic fracturing operation performed previously before step (II).
14 . The method of claim 1 , wherein step (II) is performed by utilizing at least one diversion material to direct a flow of the fracturing fluid within the wellbore.
15 . The method of claim 14 , wherein the at least one diversion material comprises at least one of a bridge plug, a packer, a downhole valve, a sliding sleeve, a baffle/plug combination, a ball sealer, sand, a ceramic material, salt, a wax, a resin, a viscosified fluid, a gelled fluid, and a foam.
16 . The method of claim 1 , wherein step (II) is carried out using a limited entry method designed to provide a pressure drop of at least 2 , 000 psi across a wall of a casing string from within the wellbore.
17 . The method of claim 1 , wherein the coke proppant particles comprise at least one of:
fluid coke;
flexicoke;
delayed coke;
thermally post-treated coke;
pyrolysis coke; and
coal-derived coke.
18 . The method of claim 1 , wherein the coke proppant particles comprise microproppant coke particles.
19 . The method of claim 1 , wherein step (II) is performed one stage after another.
20 . The method of claim 19 , wherein step (II) comprises:
injecting the fracturing fluid during an early phase of a hydraulic fracturing operation; and
injecting a second fracturing fluid comprising a carrier fluid and second proppant particles that do not comprise coke into the subterranean formation during a later phase of the hydraulic fracturing operation.
21 . The method of claim 19 , wherein step (II) comprises:
injecting a second fracturing fluid comprising a carrier fluid and second proppant particles that do not comprise coke into the subterranean formation during an early phase of a hydraulic fracturing operation; and
injecting the fracturing fluid during a later phase of the hydraulic fracturing operation.
22 . The method of claim 1 , wherein the fracturing fluid further comprises second proppant particles that do not comprise coke.
23 . The method of claim 1 , wherein the carrier fluid comprises water.
24 . The method of claim 1 , wherein the carrier fluid is substantially free of water.
25 . The method of claim 1 , wherein the fracturing fluid further comprises at least one of an acid, a biocide, a breaker, a corrosion inhibitor, a crosslinker, a friction reducer, a gel, an oxygen scavenger, a pH control additive, a scale inhibitor, a surfactant, a weighting agent, an inert solid, a fluid loss control agent, an emulsifier, an emulsion thinner, an emulsion thickener, a viscosifying agent, a foaming agent, a stabilizer, a chelating agent, a mutual solvent, an oxidizer, a reducer, and a clay stabilizing agent.
26 . The method of claim 1 , wherein step (II) comprises reopening and/or extending at least a portion of pre-existing fractures in the subterranean formation that have fully or partially closed due to proppant embedment and/or proppant degradation prior to step (II).
27 . The method of claim 1 , wherein in step (I), the subterranean formation has been previously hydraulically fractured using proppants free of coke proppants.
28 . The method of claim 1 , wherein step (II) is carried out using an extreme limited entry method designed to provide a pressure drop of at least 3,000 psi across a wall of a casing string from within the wellbore to the outside of the wellbore.