Ikelic - Alliance Digital Repository

OIL SANDS
West Newport, USA at 33 years, while the
youngest is Karajanbas, in West Kazakhstan near
the Caspian Sea, at 1 1 years. Fourteen out of
these nineteen projects are currently active. As
of April 1992, the incremental daily oil production
due to ISC was approximately 4,700 barrels of oil
per day (bbl/d) (from 8 processes) in the United
States, 8,000 bbl/d (from 10 processes) in the
former Soviet Union, 7,300 bbl/d (from
3 processes) in Canada and 12,000 bbl/d (from
5 processes) in Romania. Therefore, the 1992
world incremental daily oil production due to ISC
was about 32,000 bbl/d (from 26 reported
processes). The number of processes reported-
26~includes not only commercial but also some
semi-industrial processes, so that the oil produc
tion figure does not coincide with the Table 1
reported oil production.
Limited information is available on the commer
cial ISC projects. There is a chance that there
are other ISC commercial processes which have
been operated quietly for years.
For the commercial processes listed, the vis
cosity is in the range 5-8,000 centipoise.
The process can be applied in a wide range of
depths, from shallow to very deep reservoirs
(11,000 feet), and a wide range of permeability,
the lowest being 20 millidarcy.
The most important parameters, indicative of
economic efficiency, are AOR (Air/Oil Ratio) and
injection pressure. The AOR is in the range of
6,000 to 25,000 standard cubic feet per barrel for
Injection pressures of 200 to 3,700 psi.
Ways to Apply Commercial ISC Processes
Different types of well flooding networks may be
used for ISC applications. An idealized reservoir
with the lower zone (water/oil contact) and upper
zone distinctively marked, are shown in Figure 1.
There are two ways of applying ISC: in well pat
terns and line drive well configuration. The first
system could be applied as contiguous patterns
or isolated patterns. The location of patterns
3-24
may be upstructure or downstructure. All three
configurations have been tried, but most applica
tions used contiguous patterns and peripheral
line drive configurations. Isolated patterns were
only
process.
used in the West Newport commercial
As shown, the line drive is possible to be applied
only starting
from the upper part of the reservoir.
For this reason it is extremely important to place
the pilot upstructure. In this way, after the test is
finished, one can have both options of develop
ing to the commercial phase, that is, either line
drive or patterns.
The main advantages of the line drive over the
well pattern configuration are:
- The
- Full
- Evaluation
- Fewer
- Easier
line drive takes advantage of gravity
because the oil displacement is more
gravity stable.
avoidance of oil resaturation of the
burned area is possible.
of the process is easier
(mainly
recovery).
with respect to ultimate oil
Each producer is intercepted by the ISC
front only once. For the patterns system
as many as four ISC fronts may intercept
the producer, and the risks of damaging
the wells are higher.
artificial ignition operations are
needed with the line drive system, giving
the possibility just to make an air transfer
to the new row.
and more reliable tracking of the
ISC front is possible.
On the other hand, the main advantages of the
pattern configuration over the line drive system
are the use of different completions for injectors
and producers (including perforating different in
tervals in injectors and producers), and the
liberty to select any rate of oil production, by
THE SYNTHETIC FUELS REPORT, JANUARY 1995