King Fahd University of Petroleum and Minerals

Saudi Arabian Oil Company

Murtada Saleh Aljawad

Khalid Mohammed Alruwaili

Yevgeniy Samarkin

Mohamed Mahmoud

Salaheldin Elkatatny

Murtadha J AlTammar

Mahmoud Elsayed

Ammar El-Husseiny

Theis Solling

Xianmin Zhou

Abduljamiu Olalekan Amao

Mustafa A Al Ramadan

Ahmed Binghanim

Murtadha J Al-tammar

A method to measure acid diversion efficiency in rock samples. The method includes measuring a first porosity and a permeability of the rock samples. The method includes flooding a core region of the rock sample with a hydrochloric acid (HCl) system to create a wormhole, wherein during the flooding the HCl system penetrates from a first end of the rock sample to a second end of the rock sample to form the wormhole. The method includes measuring a second porosity, a pore size distribution, and a diffusion tortuosity of the rock samples with NMR. The method includes establishing a diversion index (DI) based off a ratio between the diffusion tortuosity in a first direction and the diffusion tortuosity in a second direction. The method includes determining the acid diversion efficiency based off the diversion index.

Method to measure acid diversion efficiency in matrix acidizing through NMR

A testing pressure vessel for permeability testing of a cured concrete sample. The testing pressure vessel includes a cylindrical pressure vessel with a sample injection port and a casing fluid injection port, and a casing fluid outlet port and an outlet port. The testing pressure vessel also includes a hydraulic inlet, and a sleeve positioned adjacent to an inner surface of the cylindrical pressure vessel and the hydraulic inlet. The testing pressure vessel further includes a plurality of pressure ports to measure a pressure exerted on the sleeve. The testing involves applying confining pressure and injection pressure to the cured concrete sample, to have the confining pressure to at least 300 psi higher than the injection pressure until a predetermined injection pressure is achieved. The testing further includes measuring the permeability of the cured concrete sample directly by measuring the pressure exerted on the sleeve.

Testing pressure vessel for cured concrete pipe sheath

Carbonates, such as chalk and limestone, are rather soft minerals and may lose at least some mechanical integrity after undergoing stimulation. For instance, carbonate minerals may experience proppant embedment or asperity weakening after fracturing or matrix acidizing. Methods for hardening a carbonate mineral may comprise: introducing an aqueous carrier fluid comprising an ammonium phosphate salt into a subterranean formation comprising a carbonate mineral, and interacting the carbonate mineral with the ammonium phosphate salt to convert at least a portion of the carbonate mineral into a hydroxyapatite mineral. The subterranean formation may exhibit an increased hardness after forming the hydroxyapatite mineral. The ammonium phosphate salt may be diammonium hydrogen phosphate in some examples.

Methods for increasing the hardness of subterranean formations

A method of treating a carbonate formation includes introducing a stimulation fluid into the carbonate formation at a pressure greater than a fracture pressure of the formation and creating openings in the carbonate formation via the stimulation fluid. Then, a fluoride salt solution, optionally including a proppant, may be introduced into the carbonate formation such that it at least partially penetrates into the openings. The fluoride salt may then be reacted with a carbonate surface in the carbonate formation to form fluorite on a surface of the formation thereby increasing a hardness of the carbonate formation.

Long-term hydraulic fracture conductivity through rock strengthening via the formation of fluorite

Growing community of inventors

Dhahran, Saudi Arabia

Murtada Saleh Aljawad