Composition of encapsulated chemical additives and methods for preparation of the same

Patent metadata

Field	Value
Publication number	US-10787600-B2
Application number	US-201816230498-A
Country	US
Kind code	B2
Filing date	Dec 21, 2018
Priority date	Jan 2, 2018
Publication date	Sep 29, 2020
Grant date	Sep 29, 2020

Abstract

Embodiments provide a method of encapsulating a solid cement additive. The method includes the step of applying a base film-forming monomer to the solid cement additive. The method includes the step of forming a coating layer surrounding the solid cement additive. The coating layer includes the base film-forming monomer. The method includes the step of applying an overlay film-forming monomer to the coating layer surrounding the solid cement additive. The method includes the step of reacting the base film-forming monomer and the overlay film-forming monomer to produce a polymer shell. The solid cement additive includes solid particles useful in cementing applications. The polymer shell includes a crosslinked polymer. The polymer shell surrounds the solid cement additive. The polymer shell has a permeability to water allowing controlled release of the solid cement additive.

First claim

That claimed is:

1. A method of encapsulating a solid cement additive for use in cementing applications, the method comprising the steps of:
applying a base film-forming monomer to the solid cement additive using at least one of a fluid dry coating method and a dry coating by hot rolling method such that a coating layer is formed surrounding the solid cement additive, the coating layer comprising the base film-forming monomer;
applying an overlay film-forming monomer to the coating layer surrounding the solid cement additive using the at least one of the fluid dry coating method and the dry coating by hot rolling method; and
reacting the base film-forming monomer and the overlay film-forming monomer to produce a polymer shell,
where the solid cement additive comprises solid particles,
where the polymer shell comprises a crosslinked polymer, the crosslinked polymer comprising aramides,
where the polymer shell surrounds the solid cement additive, and
where the polymer shell has a permeability to water allowing controlled release of the solid cement additive.

2. The method of claim 1 , where the base film-forming monomer comprises a hydrophobic monomer and the overlay film-forming monomer comprises a hydrophilic monomer.

3. The method of claim 2 , where the hydrophobic monomer is selected from the group consisting of carboxylic acid chlorides, carboxylic acid anhydrides, and combinations of the same.

4. The method of claim 2 , where the hydrophilic monomer is selected from the group consisting of para-phenylenediamine, meta-phenylenediamine, ethylenediamine, hexamethylenediamine, polyethyleneimines, polyetheramines, and combinations of the same.

5. The method of claim 1 , where the base film-forming monomer comprises a hydrophilic monomer and the overlay film-forming monomer comprises a hydrophobic monomer.

6. The method of claim 5 , where the hydrophilic monomer is selected from the group consisting of para-phenylenediamine, meta-phenylenediamine, ethylenediamine, hexamethylenediamine, polyethyleneimines, polyetheramines, and combinations of the same.

7. The method of claim 5 , where the hydrophobic monomer is selected from the group consisting of carboxylic acid chlorides, carboxylic acid anhydrides, and combinations of the same.

8. The method of claim 1 , where the solid cement additive is selected from the group consisting of set accelerators, anti-gas migration additives, viscosifying agents, fluid loss control agents, cement dispersants, retarders, salts, polymers, and combinations of the same.

9. The method of claim 1 , where the size of the solid particles is less than about 500 micrometers.

10. The method of claim 1 , where the amount of the base film-forming monomer in the coating layer is in the range from about 1 wt. % to about 25 wt. % of the solid cement additive.

11. The method of claim 1 , where the crosslinked polymer further includes polyamides.

Assignees

• Saudi Arabian Oil Co

Inventors

• Contreras Elizabeth Q
• Reddy B Raghava

Classifications

• C04B20/1037

  obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds · CPC title

• C09K8/487

  Fluid loss control additives; Additives for reducing or preventing circulation loss · CPC title

• C04B28/02

  containing hydraulic cements other than calcium sulfates · CPC title

• C09K8/467 Primary

  containing additives for specific purposes · CPC title

• C04B2103/408

  Dispersants · CPC title