Buddy Shotton, BJ-Hughes Inc.
Foams used as fracturing fluids for formation stimulation are mixtures of compressed nitrogen gas and a base liquid. The quality of a fracturing foam refers to the volumetric gas content of the foam and is usually in the range of 65-95 percent. The addition of sand to a fracturing foam can have a significant effect on the actual flow rate of the base liquid at the surface. This effect on the surface will change the foam flow rate and foam quality desired down hole. The hydrostatic pressure exerted by the fracturing foam will also be effected as sand concentration changes. Using the true volume of sand as a basis, several equations are presented in this paper which will compensate for the effects of sand concentration in foam. A well designed foam frac job is necessary for proper implementation of the stimulation treatment.