Development and On-Site Application of Integrated Device for Acidification and Water Control in Puguang Gas Field

There are some problems such as poor reservoir physical property, edge and bottom water, and inability to operate after well completion in the border blocks of Puguang Gas Field. To address these issues, an integrated device for acidification and water control was designed, and laboratory experiments were carried out to verify the performance and opening function of the device. The results show that the tensile strength, compressive strength, and sealing performance of the check injection valve of the device meet the requirements of the well test. In order to make throttling pressure drop less than 5 MPa when the flow rate is 1–5 m³/min, it is recommended that the equivalent diameter of the check injection valve should be controlled within 11.0–12.0 mm, and the total equivalent diameter is more than 36 mm. The device has been successfully tested in a gas well with a high sulfur content (Well L−X) of Puguang Gas Field, assisting the well to produce gas up to 66×10⁴ m³, and the cumulative gas production reaches 2.8×10⁸ m³ in 1.6 years, with a low liquid gas ratio of 1.7×10⁻⁵ m³/m³. Field application shows that the integrated device can meet the dual needs of acidification and water control with a set of completion strings, even though the flow rate of corresponding technologies for dual needs is significantly different. It exhibits a positive role in inhibiting the rapid coning of edge and bottom water and increasing the production degree of a single well control area, providing a tool and means to water control and production increase for edge and bottom water reservoirs that need acidification and cannot be operated later.