Open AccessOptimization and Evaluation of Stabilizers for Tight Water-Sensitive Conglomerate Reservoirs
Author(s) -
Jiayan Li,
Kun Zhang,
Ning Cheng,
Zhicheng Xing,
Song Wang,
Bin Wang,
Tianbo Liang
Publication year - 2022
Publication title -
acs omega
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.779
H-Index - 40
ISSN - 2470-1343
DOI - 10.1021/acsomega.1c06140
Subject(s) - conglomerate , hydraulic fracturing , permeability (electromagnetism) , petroleum engineering , stabilizer (aeronautics) , porosity , water injection (oil production) , fracturing fluid , montmorillonite , geology , geotechnical engineering , oil field , swelling , materials science , composite material , chemistry , geochemistry , sedimentary rock , mechanical engineering , biochemistry , membrane , engineering
The upper Wuerhe formation in the Mahu-1 play is a tight conglomerate reservoir that has characteristics of low porosity and low permeability. During the early stage of field development, it has been noticed that horizontal wells typically have a high flowback ratio and an extremely low oil production rate during the early production, and this is likely attributed to the water-rock interaction that causes the closure of generated hydraulic fractures. In this study, a stabilizer and its dosage in a fracturing fluid are optimized, and its effect on clay antiswelling and rock stabilization is evaluated. Experimental results indicate that a mixture of a salt and an inorganic cationic polymer can effectively inhibit the water-rock reaction by minimizing the clay swelling and compressing the electric double layer on the rock surface. The antiswelling rate of montmorillonite can reach 93.56%, and that of the reservoir rock powder can reach 75.32%. Meanwhile, Brazilian splitting tests are conducted to evaluate the mechanical property change of reservoir rocks before and after being submerged in fracturing fluids with different stabilizers. Compared to 4% KCl, which is currently used in the field, the new formula can enhance the breakdown pressure by more than 10% without increasing the cost. The findings of this work provide a solution for fracturing water-sensitive reservoirs and also establish a set of laboratory methods for optimizing stabilizers as fracturing fluid additives.