Development of a virtual near-wellbore mathematical model for CSG

June 2013February 2015
This research project was aimed at developing a mathematical model in this near-wellbore region which can be calibrated with small-scale laboratory experiments

Development of a virtual near-wellbore mathematical model for CSG

This discontinued project was aimed at developing a Virtual Near-wellbore Model that can be used in conjunction with existing commercial reservoir modelling software (e.g. Petrel and Skua). This project has been discontinued.

The flow of fluids through coal seams within a shaly mud has proved to be more complex than reservoir engineers expected. Typically engineers make mathematical models over the CSG reservoir to forecast the flow of gas and water from the reservoir into a pattern of wells to determine the best strategy to extract the gas. These simulations require some understanding of the small-scale flow behaviour, particularly near the wells.

This research project was aimed at developing a mathematical model in this near-wellbore region which can be calibrated with small-scale laboratory experiments and the measurements that are routinely recorded using tools that have been lowered into the well after it has been drilled but before it is configured to produce. The difficulties in understanding flow in CSG are believed to be due to a number of physical properties occurring at the same time—flow, geomechanical and particle flow in the network of cleats all combine to change the permeability magnitude and direction over time. The aim of this modelling is to link the different simulations to capture the combined effects of these phenomena.

An important secondary aim of this project was to understand the release, motion, and trapping of fine particles from the coal and the shales surrounding the coal. These fine particles can enter into the wellbore and clog the downhole pumps that are needed to lift the gas to the surface. In addition to being expensive to replace, the time taken to enter the well, retrieve the pump and then install a replacement down the hole makes this a complex logistical exercise.

This project has been discontinued.

PROJECT OUTPUTS

  • Research poster: Poster 1, UQ-CCSG Research Review (2014)
  • Research poster: Poster 2, UQ-CCSG Research Review (2014)
  • Project status: Ceased - this project has been discontinued
  • Project title: Development of a virtual near-wellbore mathematical model for CSG
  • Project leader: Professor Steve Tyson
  • Research group: The University of Queensland Centre for Coal Seam Gas
  • Timeframe: June 2013 - February 2015
  • Project funders: APLNG, Arrow Energy, Santos, QGC, University of Queensland