Composite cement compositions and methods of cementing and/or treating wells drilled with water-based drilling fluids
Composite cement compositions and slurries for treating a well following a water-based wellbore operation are provided and comprise cement comprising at least one of cement particles and cementitious material, water, and water swellable particulates that are embedded in the cement, derived from an elastomeric material, and present at a concentration of at least about 2% by weight of the cement but no more than about 30% by weight of the cement. Methods for treating a well drilled with a water-based drilling mud are provided and comprise pumping the composite cement compositions and slurries into the well and treating the well by allowing the composite cement compositions and slurries to set or cure after being pumped into the well.
1 . A composite cement slurry comprising:
cement including one or more of cement particles or cementitious material; and
water swellable particulates that are embedded in the cement, wherein the water swellable particulates consist of:
a hydrophilic swellable polymer; and
an elastomeric material doped with the hydrophilic swellable polymer.
2 . The composite cement slurry of claim 1 , further comprising water.
3 . The composite cement slurry of claim 2 , wherein the hydrophilic swellable polymer is present within the elastomeric material such that a water swelling of the water swellable particulates is prevented during a time duration after the cement, the water, and the water swellable particulates are mixed together.
4 . The composite cement slurry of claim 3 , wherein the time duration is at least about 2 hours and no more than about 4 hours.
5 . The composite cement slurry of claim 1 , wherein the water swellable particulates have a delay swelling mechanism provided by the elastomeric material, the delay swelling mechanism configured to limit swelling of the water swellable particulates during at least one of mixing or pumping of the composite cement slurry.
6 . The composite cement slurry of claim 5 , wherein the delay swelling mechanism is configured to delay the swelling of the water swellable particulates to between about 2.5 and about 3.5 hours.
7 . A method of implementing a cement slurry, comprising:
obtaining a cement including:
one or more of cement particles or cementitious material; and
water swellable particulates embedded in the cement;
hydrating the cement by mixing the cement with water;
based on a delay swelling mechanism of the water swellable particulates, delaying swelling of the water swellable particulates during the hydrating of the cement, wherein delaying the swelling of the water swellable particulates with the delay swelling mechanism is based on the water swellable particulates consisting of a hydrophilic swellable polymer and an elastomeric material doped with the hydrophilic swellable polymer; and
causing the water swellable particulates to react with the water and swell during a thickening of the cement.
8 . The method of claim 7 , wherein delaying the swelling of the water swellable particulates with the delay swelling mechanism includes controlling a water-absorbing property of the water swellable particulates based on the water swellable particulates including one or more superabsorbent moieties sufficient to limit the swelling of the water swellable particulates until the thickening of the cement.
9 . The method of claim 7 , wherein delaying the swelling of the water swellable particulates with the delay swelling mechanism is based on the water swellable particulates exhibiting a negative charge repulsion.
10 . The method of claim 9 , wherein the negative charge repulsion is attached to a functional group of the elastomeric material.