Clay swelling, dispersion and migration due to water-sensitive clay minerals in the producing formation can substantially reduce rock and retained proppant permeability resulting in reduced well productivity. The effects of water-based fracturing fluids in water-sensitive formations have been extensively investigated which led to development of different types of clay stabilizers based on type of clays, bottomhole temperature, and clay protection time. The use of KCl or NaCl brine up to concentration of 6% is well known clay stabilizing method for swellable and migratory clays during the stimulation treatment.
However, using high salt content brines have some limitations and constrains. The performance of crosslinkers (Borate or Zirconium) and breakers are often affected when using high salt concentration in the base fracturing fluids. The sandstone formations of Saudi Arabia have been reported to be "water-sensitive" and can be easily damaged by fresh water. A novel clay stabilization liquid additive has been successfully introduced as a substitute to inorganic salts in fracturing fluids for sandstone formation in Saudi Arabia. This new permanent clay control additive is cationic polymer with ultra-low molecular weight (PC-4) and compatible with borate and zirconium crosslinkers. It also reduces safety concerns and operational time by eliminating handling and mixing of huge amount of salts on location.
This paper provides details on lab testing, and field implementation of the novel cost effective clay control additive in HTHP sandstone gas well during proppant fracture treatment.