The reverse combustion method can be applicable, in principle, to ultra heavy oils as an EOR method. However, the low recovery efficiency of the reverse combustion method, as is known, seems to dismiss this advantage.
As a part of research work for improving the recovery efficiency by the reverse combustion method, it was intended, first of all, to investigate general behaviors of the reverse combustion through combustion tube experiments, because very few works in this area had been done. And the influence of oxygen injection rate was investigated as a first part. Results are summarized as follows.
(1) In the reverse combustion, the combustion zone can be maintained at a temperature lower than 400°C that is the critical temperature in the forward combustion. This means that the fuel in the reverse combustion is not a cork but light components of oil.
(2) The temperature of combustion zone increases as the injection rate of oxygen increases.
(3) The propagation speed of combustion front increases with the oxygen injection rate.
(4) There is an optimum injection rate of oxygen to obtain a maximum recovery.
(5) The maximum recovery in the reverse combustion of a partiucular crude oil of 0.938 in specific gravity was 58%, whereas that in the forward combustion was 90%.
抄録全体を表示