Evaluation of Dual Injection Methods for Multiple Zone Steamflooding

ABSTRACT For multiple oil zone reservoirs, it is advantageous to steam flood two zones at the same time to take advantage of overburden heating. To have adequate control over injection rates to each zone and provide injection streams with different steam qualities or water temperatures, two separate injection streams are required. With injection wells already in place, the most economical method is to use the same injection well to flood two zones simultaneously. Three dual injection methods were tried and tested at Texaco's Kern River Field in Bakersfield, California. Because dual injection results in an excessive amount of heat transfer between injection streams, it was imperative to predict steam quality or water temperature at the sandface for each injection stream. To adequately evaluate the merits of each method, a computer model was written to predict downhole temperatures, steam qualities, and pressures of each injection stream. Field tests of the three injection configurations provided measurements necessary for the validation of the model. This paper describes the computer model, the field test and the results from the three dual injection scenarios.