ABSTRACT
A new type of fracturing fluid containing partially hydrolyzed methylene polyacrylamide crosslinked by multivalent metal ions is investigated as thickening agent and friction reducer, while persulfate, H2O2, perborate or hydrazine are used as breaking agent.
In comparison with conventional fracturing fluid, this fluid, possesses a number of advantages, such as no residue, better thickening ability, lower friction loss, better shear stability, good resistance to high salinity, better temperature-viscosity property etc. This fracturing fluid has been used successfully in hydrulic fracturing treatments in low permeabl formation and excellent results have been obtained in fracturing treatments for deep well (140°C) and injection well. In addition, this fracturing fluid can easily be prepared on-site and the operation is simple.