Crisman Annual Report 2009 - Harold Vance Department of ...

Study of Solvent-Based Emulsion Injection to Improve Sweep and Displacement
Efficiency in Heavy Oil Reservoir
Introduction
About two-thirds of the original oil in reservoirs is left
behind, even after gas injection or water-flooding.
However most of the oil contacted by a solvent
may be recovered, as a solvent is miscible with
reservoir oil. Unfortunately, the low solvent viscosity
results in unfavorable mobility ratio and poor sweep
efficiency particularly in heavy oil reservoirs. Thus
this research investigates residual oil reduction
by solvent and sweep efficiency improvement by
emulsion.
Objectives
This research has two parts:
Experimental research
Main objectives are as follows:
» Investigate the feasibility of solvent-based
emulsion flooding to improve displacement and
sweep efficiency in heavy oil reservoirs
» Conduct core-flood experiments to compare
recovery efficiency using various emulsions after
water-flooding.
Fig. 1. Emulsion ternary phase diagram.
the ternary phase diagram shown in Fig. 1. Emulsion
containing 5wt% silica nanoparticles shows a higher
viscosity than emulsion without nanoparticles (Fig.
2). Cores have been scanned to measure porosity
and initial oil and water saturations (Fig. 3).
Simulation study
Main research objectives are as follows:
» Perform history matching of the experimental
results using CMG
» Conduct simulation study of sweep efficiency in a
5-spot well pattern.
Approach
This research has two parts, namely, experiments
and simulation study. First, a bench test is performed
to get the emulsion system properties, such as
viscosity, IFT, and ternary phase diagram. Based on
the bench test results, the optimized emulsions are
chosen to perform the core flooding experiments.
Second, different core flooding experiments are
conducted to investigate the effect of these emulsions
on oil recovery. The aluminum coreholder will be
x-ray CT scanned to measure residual oil saturation
in the core. Lastly, a simulation will be conducted
to history match the experiment results to enable a
study of sweep efficiency for a 5-spot well pattern.
Accomplishments
The bench tests have been completed. The results
showing micro- and macro-emulsions are plotted in
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Project Information
1.3.20 Microemulsion-Solvent Injection to Improve Sweep
and Displacement Efficiency of Heavy and Light Oil
Related Publications
Willhite, G.P., Green, D.W., Okoye, D.M., and Looney, M.D.
A Study of Oil Displacement by Microemulsion Systems:
Mechanisms and Phase Behavior. SPE-7580.
Contacts
Daulat Mamora
979.845.2962
daulat.mamora@pe.tamu.edu
Fangda Qiu
CRISMAN INSTITUTE
Crisman Annual Report 2009