Theoretical and Experimental Studies of Sandstone Acidizing

Abstract The matrix acidization of sandstone by a hydrochloric/hydrofluoric acid mixture is described through use of a capillary model. The model was solved first in linear coordinates so that it could be compared with the results of coreflood experiments performed on Berea sandstone. The model predictions showed reasonable agreement with the experimental data and yielded specific information about the reaction characteristics of the sand-stone/HCl/HF system. The acidization model then was applied in radial coordinates to generate design curves for a matrix acidization treatment. While these curves strictly apply only to those sandstones having similar mineral compositions, the approach is general. It is based on matching the location of the HF reaction front to the depth of a damaged zone. This method introduces the concept of an optimum injection rate and, in this regard, differs from other design methods reported in the literature.

Theoretical and Experimental Studies of Sandstone Acidizing Academic Article