Cement slurries, cured cement and methods of making and use thereof

Patent metadata

Field	Value
Publication number	US-2020131427-A1
Application number	US-201916675820-A
Country	US
Kind code	A1
Filing date	Nov 6, 2019
Priority date	Oct 25, 2018
Publication date	Apr 30, 2020
Grant date	—

Abstract

Cement slurries, cured cements, and methods of making cured cement and methods of using cement slurries are provided. The cement slurries have, among other attributes, increased yield point, reduced density, improved mechanical properties, increased resistance to H 2 S, and may be used, for instance, in the oil and gas drilling industry. The cement slurry comprises cement precursor material, Saudi Arabian volcanic ash, and an aqueous solution. The Saudi Arabian volcanic ash comprises SO 3 , CaO, SiO 2 , Al 2 O 3 , Fe 2 O 3 , MgO, and K 2 O and the cement slurry is free of any other SiO 2 additive.

First claim

What is claimed is:

1 . A method of cementing a casing in a wellbore comprising:
mixing cement precursor material, Saudi Arabian volcanic ash acquired from Saudi Arabia, and an aqueous solution to form a cement slurry, in which the Saudi Arabian volcanic ash comprises SO 3 , CaO, SiO 2 , Al 2 O 3 , Fe 2 O 3 , MgO, and K 2 O and the cement slurry is free of any other SiO 2 additive; introducing the cement slurry into an annulus between the casing and the wellbore; and curing the cement slurry to cement the casing in the wellbore.

2 . The method of claim 1 , in which the Saudi Arabian volcanic ash has a particle size of from 20 to 30 μm.

3 . The method of claim 1 , in which the Saudi Arabian volcanic ash is free of TiO 2 .

4 . The method of claim 1 , in which the Saudi Arabian volcanic ash comprises from 0.05 wt. % to 0.2 wt. % SO 3 .

5 . The method of claim 1 , in which the Saudi Arabian volcanic ash comprises:
from 0.05 wt. % to 0.2 wt. % SO 3 ; from 5 wt. % to 10 wt. % CaO; from 40 wt. % to 50 wt. % SiO 2 , from 10 wt. % to 20 wt. % Al 2 O 3 ; from 10 wt. % to 15 wt. % Fe 2 O 3 ; from 5 wt. % to 10 wt. % MgO; and from 0.5 wt. % to 5 wt. % K 2 O.

6 . The method of claim 1 , in which the cement slurry comprises from 8 to 60 wt. % BWOC Saudi Arabian volcanic ash.

7 . The method of claim 2 , in which the cement precursor material comprises one or more components selected from the group consisting of calcium hydroxide, silicates, belite (Ca 2 SiO 5 ), alite (Ca 3 SiO 4 ), tricalcium aluminate (Ca 3 Al 2 O 6 ), tetracalcium aluminoferrite (Ca 4 Al 2 Fe 2 O 10 ), brownmilleriate (4CaO.Al 2 O 3 .Fe 2 O 3 ), gypsum (CaSO 4 .2H 2 O) sodium oxide, potassium oxide, limestone, lime (calcium oxide), hexavalent chromium, trivalent chromium, calcium aluminate, and combinations thereof.

8 . The method of claim 1 , in which the cement slurry has a density of from 110 to 160 lb/ft 3 and a yield point of from 5 to 70 lbf/100 ft 2 .

9 . The method of claim 1 , in which the method further comprises adding one or more additives selected from the group consisting of dispersants, fluid loss control agents, retarders, expansion additives, antifoaming agents, stabilizers, accelerators, extenders, weighting agents, lost circulation control agents, surfactants, gypsum, hematite, manganese tetroxide, silica flour, and silica sand.

Assignees

• Saudi Arabian Oil Co

Inventors

• Alsaihati Zainab
• Al-Yami Abdullah
• Wagle Vikrant
• Al-Awadh Abdullah
• Alhelal Abdulaziz
• Alhareth Nasser

Classifications

• C04B2201/20

  for the density · CPC title

• C04B28/14

  containing calcium sulfate cements {(gypsum-paper plates E04C)} · CPC title

• C09K8/473 Primary

  Density reducing additives, e.g. for obtaining foamed cement compositions · CPC title

• C04B14/14

  Minerals of vulcanic origin {(granite C04B14/048)} · CPC title

• E21B33/14

  for cementing casings into boreholes · CPC title