Field Application of an HCI/Formic Acid System to Acid Fracture Deep Gas Wells

摘要

Gelled and in-situ gelled hydrochloric acid(HCI)/formic acid(H.COOH)systems were optimized to stimulate deep gas wells completed with Super-13-Cr tubing.High temperatures in deep wells and the susceptibility of Super 13 cr to severe corrosion caused by concentrated HCI solutions and high chloride-ion concentrations make acid stimulation a very difficult task.Extensive experimental and field studies were performed to develop a costeffective acid system to improve productivity of deep gas wells,while maintaining the integrity of the Super-13-Cr tubing.