Abstract:
Acoustic wave detection systems are designed to estimate distances based on the
measurement of the time of arrival (TOA) of an ultrasonic wave. It has been used in
diagnoses and treatments in areas such as medicine, dentistry, civil engineering, and
many other industrial applications. It has also been applied in the oil industry for pipeline
inspection and fluid velocity measurement.
In this study, a comprehensive experimental program was designed and conducted
to evaluate the feasibility of using acoustic waves for detection and monitoring of vapor
chamber growth and pressure front movement in porous media during vapor chamber
expansion in the VAPEX process. Vapor extraction is a potential nonthermal recovery
process used to improve the recovery factor from heavy oil and bitumen reservoirs. In
this process, a mixture of light hydrocarbon vapors close to its dew-point, such as
propane or butane, is injected into the reservoir through a horizontal injection well. As the
solvent vapor comes into contact with the heavy oil, it dissolves in the oil and reduces its
viscosity. The mobilized oil then drains into the second horizontal production well. After
the breakthrough of the vapor chamber from injection to production well, the vapor
chamber begins to grow and more oil becomes mobilized by interaction with the solvent
chamber.
The simulated VAPEX chamber in this study was conducted by using different
sized air balloons buried in a water- or oil-saturated sand pack. The ultrasound receivers were placed on the physical model to detect the acoustic signals from the transducers. A
MatlabTM based program was developed to do the signal processing using wavelet signal
transform technique to extract the position of the echo signal from the signal record; the
size and shape of the air balloons were determined based on the TOF of the ultrasonic
signal record. The results of the measurements and simulations show that ultrasound
detection system is applicable to test the shape and growth of simulated VAPEX chamber
in a lab scale; the image results of the simulated lab model are reliable. It is the first time
that such a technique has been proposed for this purpose and it was proven effective on a
laboratory scale.
Description:
A Thesis Submitted to the Faculty of Graduate Studies and Research In Partial Fulfillment of the Requirements for the Degree of Master of Applied Science in Electronic Systems Engineering, University of Regina. XVI, 125 p.