Flow of Gas-liquid Mixtures through Consolidated Sand

Abstract

Experiments performed in this laboratory on the flow of gas-liquid mixturesthrough unconsolidated sands have been described and discussed in an earlierpaper. In these earlier experiments a definite relationship was found betweenthe liquid saturation of a sand and its permeability to the liquid or gasphase. Furthermore, the nature of the sand, the permeabilities of the sandsover a range between 17 and 260 darcies, appeared to have a negligible effectupon the saturation-permeability relation. Likewise experiments indicated thatthe viscosity of the liquid, or the substitution of an immiscible liquid forthe gas phase, had only a very slight effect on the permeability-saturationrelation. This conclusion has since been definitely confirmed by theexperiments of M. C. Leverett on the flow of oil and water throughunconsolidated sands. The sands used by Leverett were of very low permeability(between 6.8 and 1.04 darcies), while the oil-water viscosity ratio variedbetween 90 and 0.057. Since the sands that constitute petroleum reservoirs are largely consolidated, although of widely varying degrees of consolidation, it was desirable to extendthe experiments on gas-liquid mixtures to consolidated sand. In the study ofconsolidated sands additional variables are involved, but for the initialexperiments the only new variable to be introduced was the cementingmaterial. Experimental Procedure A comparatively limited assortment of sandstones was available for theselection of the experimental material. Of these, the Nichols buff sandstoneappeared to be most suitable. It gives no visual evidence of any beddingplanes, it has a firm structure, permitting easy handling, and its permeabilityis about 0.5 darcy. Its only disadvantage is the fact that It contains anappreciable amount of ferric oxide which, for experiments involving water, willhydrate and reduce the permeability. T.P. 1111