Case Study on Preformed Particle Gel for In-Depth Fluid Diversion

TLDR

The study examines preformed particle gel (PPG) treatments for in‑depth fluid diversion in four injection wells of the sandstone Lamadian oilfield in Daqing, China. The authors aim to detail the well‑selection criteria, PPG optimization, real‑time monitoring, reservoir performance, and to explain the feasibility of injecting large‑particle PPG into the reservoir. Four injectors with 46 connected producers (average water cut 95.4 %) received 2,000–2,500 mg/L PPG suspensions (0.06–3.0 mm particles) over ~4 months, with injection volumes of 11,458–17,625 m³ per well (total 56,269 m³, 295,680 lb dried), while maintaining stable wellhead pressure and monitoring pressure, rate, and particle‑size changes. The treatments increased oil production by 34.8 t/d and reduced average water cut by 0.94 % within ten months post‑treatment.

Abstract

Abstract The paper describes preformed particle gel (PPG) treatments for in-depth fluid diversion in four injection wells located in the north of Lamadian, Daqing oilfield, China. Lamadian is sandstone oilfield with thick net zones. The selected four injectors have 46 connected producers with average water cut of 95.4% before treatment. The paper reports the detailed information for the four well treatments, including well candidate selection criteria, PPG treatment optimization, real-time monitoring result during PPG injection and reservoir performance after treatment. In addition, a discussion is made to analyze why so large amount of large particles can be injected into the reservoir. Large volume of PPG suspension with concentrations of 2,000–2,500 mg/L and particle sizes of 0.06–3.0 mm was injected into each well and it took about 4 months to finish each injection. The injection volume ranges from 11,458 to 17,625 m3 per well with a total of 56,269 m3 of PPG suspension (295,680 lbs of dried PPG) for the four wells. During PPG injection, the increase of the wellhead pressure was quite stable and no PPG was produced from adjacent producers. Recorded real-time monitoring Data about injection pressure and rate, PPG particle size change during PPG injection provide invaluable information to analysis the possibility of fracture/channel in the reservoir. The treatments resulted in an oil increase of 34.8 t/d and average water cut decrease of 0.94% within 10 months after treatments.