Sand Fracturing With Liquid Carbon Dioxide

The search for cleaner fracturing fluids has led to the development of sand fracturing using liquid CO/sub 2/ as the proppant carrier fluid. CO/sub 2/ is handled at the surface as a liquid at approx. 200 psi and -30/sup 0/F. Special blending equipment has been developed to inject proppant directly into the liquid CO/sub 2/ at these surface conditions. Then, the sand laden liquid CO/sub 2/ is pumped by conventional equipment. At stabilized reservoir temperature and pressure, the liquid CO/sub 2/ vaporizes in a gas well or vaporizes and is partially dissolved in the reservoir oil in an oil well. The greatest potential of liquid CO/sub 2/ fracturing is the elimination of most of the formation damage normally associated with fracturing fluids and the very rapid clean up and evaluation of the well following the stimulation. 12 references.