In-situ combustion is an enhanced recovery technique offering many adv
antages over other enhanced recovery processes in heavy-oil reservoirs
, such as a more efficient overall drive mechanism, less energy consum
ption, and less total environmental impact. Although this process has
been extensively studied in both the laboratory and the field, it has
failed to achieve general acceptance because of the small number of su
ccessful field applications. Many of the failures resulted from inappr
opriate applications of the fireflooding process, which, in turn, aros
e from misconceptions about the way in-situ combustion works. This pap
er will discuss recent advances in the authors' understanding of combu
stion kinetics, examine some of the mechanisms that led to the failure
of several Canadian heavy-oil projects, and offer suggestions on how
the correct oxidation mode can be encouraged in a fireflood operation.
Several promising field strategies, including the use of horizontal p
roduction wells, will also be presented.