US 12,480,899 B2
Method to measure acid diversion efficiency in matrix acidizing through NMR
Mahmoud Elsayed, Dhahran (SA); Mohamed Mahmoud, Dhahran (SA); Murtada Saleh Aljawad, Dhahran (SA); Ammar El-Husseiny, Dhahran (SA); and Ahmed Binghanim, Dhahran (SA)
Assigned to KING FAHD UNIVERSITY OF PETROLEUM AND MINERALS, Dhahran (SA)
Filed by KING FAHD UNIVERSITY OF PETROLEUM AND MINERALS, Dhahran (SA)
Filed on Dec. 8, 2022, as Appl. No. 18/077,738.
Prior Publication US 2024/0192155 A1, Jun. 13, 2024
Int. Cl. G01N 24/08 (2006.01); G01N 15/08 (2006.01); G01N 33/24 (2006.01)
CPC G01N 24/081 (2013.01) [G01N 15/08 (2013.01); G01N 33/24 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A method to measure acid diversion efficiency in a rock sample, comprising:
measuring a first porosity and a permeability of the rock sample;
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;
measuring, with NMR, a first diffusion tortuosity τd,x in an X-direction corresponding to a direction orthogonal to the wormhole;
measuring, with NMR, a second diffusion tortuosity τd,y in a Y-direction corresponding to a direction parallel to the wormhole;
calculating a diversion index (DI) by the following formula:

OG Complex Work Unit Math