Acidizing

Stimulation & Fracturing

Acidizing is a stimulation treatment involving the pumping of acid (usually Hydrochloric [HCl] or Hydrofluoric [HF] acid) into the well to dissolve rock and improve permeability. In carbonate reservoirs (limestone/dolomite), 'matrix acidizing' dissolves wormholes to bypass formation damage.

In sandstone reservoirs, acid is used primarily to dissolve damaging clays or drilling mud solids near the wellbore. Acid fracturing involves pumping acid at pressures above fracture gradient to etch the face of the fracture, creating uneven surfaces that keep the fracture open without proppant.