TH33461A - Cement mixtures and methods for use in underground wells - Google Patents

Abstract

DC60 (05/07/43) provides a cement mixture consisting of hydraulic cement, iron chloride, and sufficient water to form a pumpable slurry. Iron chloride predictably improves the morphology and performance of the mixture, resulting in a method for cementing underground wells. The process involves mixing the hydraulic cement, iron chloride, and sufficient water to form a pumpable slurry; pumping the slurry to a pre-selected location within the well; and then allowing the slurry to harden inside the well.

Claims (20)

1. The method of cementing a well consists of the following steps: preparing a cementitious mixture containing hydraulic cement with more than approximately 0.3% alkali sulfate by weight; sufficient water to create a pumpable slurry; and iron chloride ranging from approximately 0.1% to approximately 10% by weight of the cement; pumping the slurry into the well; and allowing the slurry to harden inside the well. 2. The method under claim 1 which selects the said iron chloride from ferrous chloride, ferric chloride or a mixture of such substances. 3. The method under claim 1, which is Portland cement. 4. The method under claim 1, which involves the presence of iron chloride ranging from approximately 0.5% to approximately 2% by weight of cement in the mixture. 5. The method under claim 1, which involves water ranging from approximately 20% to approximately 150% by weight of cement in the mixture. 6. The method under claim 1, in which the cement contains more than approximately 0.5% by weight of alkali sulfate. 7. The method under Claim 1, in which the cement contains more than approximately 1.0% by weight of alkali sulfate. 8. The method under claim 1, in which the cement contains more than approximately 1.5% by weight of alkali sulfate. 9. The method of cementing a well consists of the following steps: preparing a cement-binding mixture containing Portland cement with more than approximately 0.3% by weight of alkali sulfate; sufficient water to create a pumpable slurry; and iron chloride salts from ferrous chloride, ferric chloride, or a mixture of these, in amounts ranging from approximately 0.1% to approximately 10% by weight of the cement; pumping the slurry into the well; and allowing the slurry to harden inside the well. 10. The method under claim 9 involves the presence of iron chloride ranging from approximately 0.5% to approximately 2% by weight of cement in the mixture. 11. The method under claim 9 involves water ranging from approximately 20% to approximately 150% by weight of cement in the mixture. 12. The method under claim 9, in which the cement contains more than approximately 0.5% by weight of alkali sulfate. 13. The method under claim 9, in which the cement contains more than approximately 1.0% by weight of alkali sulfate. 14. The method under claim 9, in which the cement contains more than approximately 1.5% by weight of alkali sulfate. 15. The method of cementing a well consists of the following steps: preparing a cement-bonded mixture containing hydraulic cement with an alkali sulfate content of approximately 0.3% by weight of the mixture; incorporating water ranging from approximately 20% to approximately 150% by weight of the cement in the mixture; and selecting iron chloride from ferrous chloride, ferric chloride, or a mixture of them, in a quantity ranging from approximately 0.1% to approximately 10% by weight of the cement; pumping the slurry into the well; and allowing the slurry to harden inside the borehole. 16. The method under claim 15 involves the presence of iron chloride ranging from approximately 0.5% to approximately 2% by weight of cement in the mixture. 17. The method pursuant to claim 15, which is Portland cement. 18. The method under claim 15, in which the cement contains more than approximately 0.5% by weight of alkali sulfate. 19. The method under claim 15, in which the cement contains more than approximately 1.0% by weight of alkali sulfate. 20. The method under claim 15, in which the cement contains more than approximately 1.5% by weight of alkali sulfate.