Settling Behavior And Mechanism Analysis Of Kaolinite As A Fracture Proppant Of Hydrocarbon Reservoirs In CO2 Fracturing Fluid

Abstract

Applying CO₂ fracturing fluid to enhance oil recovery efficiency has recently attracted increasing attention in the hydrocarbon development from unconventional shale reservoirs, and the sedimentation behavior of proppant particles in fracture fluid directly affects the fracture propping and crude oil production. This study investigates the sedimentation applicability of kaolin as a fracture proppant in CO₂ fracturing fluids of shale fractures, and CO₂ fracturing fluid multi-performance coupling evaluation equipment was performed to investigate the effects of various factors on the settlement ability of kaolinite particles in shale fractures. Additionally, the adsorption model of CO₂ thickener on kaolinite surface and the three-dimensional grid structure of fracturing fluid were constructed to assist in revealing the settling mechanism of kaolinite in CO₂ fracturing fluid. The results indicated that the suspension ability of kaolinite proppant by CO₂ fracturing fluid in shale reservoir fractures is significantly impacted by the particle properties. An increase in diameter will promote the settling ability of kaolinite particles, while the roughness of the kaolinite surface is effective in slowing down the rapid sinking of proppant. In addition, fracture pressure and reservoir temperature produce completely opposite trends of the kaolinite sedimentation in fracture fluid, and the towage of the microscopic grid of the fracturing fluid and the adsorption of CO₂ thickener on the kaolinite surface are considered to be the primary factors influencing the kaolinite sedimentation. This investigation not only paves a new avenue for kaolinite particles as fracture proppants in shale reservoirs, but also provides an efficient proposal for the reduction of kaolinite sedimentation and the adsorption of CO₂ thickener on the kaolinite.

Department(s)

Geosciences and Geological and Petroleum Engineering

Second Department

Chemical and Biochemical Engineering

Comments

Henan Provincial Science and Technology Research Project, Grant 242102320342

Keywords and Phrases

Clay particle settling; CO2 fracturing fluid; Hydrocarbon prospection; Kaolinite proppant; Microscopic adsorption; Shale reservoirs

International Standard Serial Number (ISSN)

1873-4359; 0927-7757

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2025 Elsevier, All rights reserved.

Publication Date

05 Nov 2025

Link to Full Text

Share

 
COinS