Micromechanics of perforation penetration and sand production in weak sandstone formations in Kazakhstan

  • Zhao, Yong (PI)
  • Fok, Sai Cheong , (CoI)
  • Nguyen, Minh, (PI)
  • Shabdirova, Ainash (PhD student/Master degree holder)
  • Kozhagulova, Ashirgul (PhD student/Master degree holder)
  • Rakhimzanova, Aigerim (PhD student/Master degree holder)
  • Khamitov, Furkhat (PhD student/Master degree holder)

Project: Research project

Grant Program

ORAU Grant

Project Description

The goal of this project is to investigate the micromechanics of sand production in weak sandstone formations using laboratory
experiments of the perforation and sand production processes, which are combined with modeling works using a microscopic
coupled modeling technique of Discrete-Element-Method (DEM) and Computational-Fluid-Dynamics (CFD) and a FEM modeling
of boundary value problems. The effects of the formation damages (due to perforation) on the sanding initiation and sanding
severity over a well-life will be investigated. The research outcomes will contribute to the development of well completion and
flow assurance technologies and to the optimization of oil production; these are among the major technical challenges defined in
the 2025 horizon R&D roadmap of the oil-gas industries in Kazakhstan.

Key findings

- The behaviors of the weak sandstone have been investigated by both experimental and numerical studies and it has been concluded that the failure of the material is dominated by the bond breakage behavior, the maximum strength of the material that is usually used in the stability analysis of wellbore is achieved at about 50% bond breakage. Materials behave essentially frictional as large deformation when the effect of the initial cemented structure has been eradicated. These results are reported in two journal papers under review process.
- Based on collected field data, a new analytical model for sanding prediction of perforation tunnels has been developed for the oil wells in Kazakhstan. The results are discussed in a journal paper under review process. The model is being further developed by being calibrated against the sand production experimental data in our laboratory with an emphasis on the change of porosity and permeability of the plastic zone around the perforation, as well as with the consideration of fluid-structure interaction with mass conservation during sand production. The prediction of sand production from perforation for very weak sandstone like in Kazakhstan is a great challenge and establishing a prediction method as in our work is novel and very significant for practical works for oil and gas companies.
- Numerical methods and procedures have been developed for the modelling of sand production from perforation tunnels especially the interaction between a multiphase flow and a degrading cemented sandstone, the results of which are discussed in two conference papers and one journal paper. These on-going works are important to understand sand production when wells produce oil at different water cut values and can be considered at the cutting edge of sand production research in both academic and industrial researches.
Effective start/end date1/1/1512/31/18


discrete element method
well completion
gas industry
computational fluid dynamics
oil industry
oil production