Fluid loss control additive
AssigneeSaudi Arabian Oil Company
InventorsPeter Boul, Kenneth Dejuan Johnson
Life of this patent
Estimating the term…
Abstract
Fluid loss control additives for a cement slurry are provided. An exemplary fluid loss control additive includes a copolymer containing 2-acrylamido-2-methylpropane sulfonic acid monomer units and acryloylmorpholine monomer units, and a graft copolymer. The graft copolymer contains a humate and, grafted onto the humate, a side-chain polymer containing at least one of acrylamide monomer units, acryloylmorpholine monomer units, acrylic acid monomer units, and 2-acrylamido-2-methylpropane sulfonic acid monomer units.
Claims28
A fluid loss control additive comprising:
- a copolymer comprising 2-acrylamido-2-methylpropane sulfonic acid monomer units and acryloylmorpholine monomer units;
- and
- a graft copolymer comprising a humate and, grafted onto the humate, a side-chain polymer comprising:
- acrylamide monomer units;
- acryloylmorpholine monomer units;
- acrylic acid monomer units;
- and
- 2-acrylamido-2-methylpropane sulfonic acid monomer units;
- wherein:
- the acrylamide monomer units comprise about 10% to about 40% of a total number of monomer units of the side-chain polymer;
- the acryloylmorpholine monomer units comprise about 5% to about 35% of a total number of monomer units of the side-chain polymer;
- the acrylic acid monomer units comprise about 10% to about 40% of a total number of monomer units of the side-chain polymer;
- and
- the 2-acrylamido-2-methylpropane sulfonic acid monomer units comprise about 20% to about 75% of a total number of monomer units of the side-chain polymer.
A slurry, comprising:
- water;
- a cement;
- a copolymer of 2-acrylamido-2-methylpropane sulfonic acid monomer units and acryloylmorpholine monomer units;
- and
- a graft copolymer comprising a humate and, grafted onto the humate, a side-chain polymer comprising:
- acrylamide monomer units;
- acryloylmorpholine monomer units;
- acrylic acid monomer units;
- and
- 2-acrylamido-2-methylpropane sulfonic acid monomer units;
- wherein:
- the acrylamide monomer units comprise about 10% to about 40% of a total number of monomer units of the side-chain polymer;
- the acryloylmorpholine monomer units comprise about 5% to about 35% of a total number of monomer units of the side-chain polymer;
- the acrylic acid monomer units comprise about 10% to about 40% of a total number of monomer units of the side-chain polymer;
- and
- the 2-acrylamido-2-methylpropane sulfonic acid monomer units comprise about 20% to about 75% of a total number of monomer units of the side-chain polymer.
A method of controlling fluid loss of a cement slurry, the method comprising mixing, in any order:
- water;
- a cement;
- a copolymer comprising 2-acrylamido-2-methylpropane sulfonic acid monomer units and acryloylmorpholine monomer units;
- and
- a graft copolymer comprising a humate and, grafted onto the humate, a side-chain polymer comprising:
- acrylamide monomer units;
- acryloylmorpholine monomer units;
- acrylic acid monomer units;
- and
- 2-acrylamido-2-methylpropane sulfonic acid monomer units;
- wherein:
- the acrylamide monomer units comprise about 10% to about 40% of a total number of monomer units of the side-chain polymer;
- the acryloylmorpholine monomer units comprise about 5% to about 35% of a total number of monomer units of the side-chain polymer;
- the acrylic acid monomer units comprise about 10% to about 40% of a total number of monomer units of the side-chain polymer;
- and
- the 2-acrylamido-2-methylpropane sulfonic acid monomer units comprise about 20% to about 75% of a total number of monomer units of the side-chain polymer.
Dependencies are inferred from the claim text.