Reservoir Damage Mechanism And Treatment Technology In Qian'an Oilfield

Qian'an oilfield, which has difficulties in oil well stable production currently and whose requirements of oil well stable production can not be met only by hydraulic fracturing measurement, is a typical three-low oilfield. Based on the careful study of Qian'an oilfield geological condition, combined with the existing problems in Qian'an oilfield drilling and fracturing development process, Qian'an oilfield reservoir damage mechanism is studied in this paper. The research founds the following results. Reservoir shale content in Qian'an oilfield is high, which may easily cause water sensitivity and water block damage. Oil well water-exit salinity is high, which may easily cause scale plugging. Fracturing fluid residue is serious, which may easily pollute the reservoir. Crude oil wax content and freezing point are high, which may easily cause organic reservoir plugging. In a word, reservoir damage in Qian'an oilfield is serious and effective treatment measures must be taken to reduce reservoir damage.In this paper, aiming at seriouse reservoir damage in Qian'an oilfield, using the three technology of fracture cleaning, acidization plug removal by mud acid and high negative pressure compound deplugging, reservoir damage by drilling and fracturing is effectively reduced, oil well production ability is restored, stimulation effect is significant, oil well composite decline is effectively delayed and an effective guarantee is provided for Qian'an oilfield stable production. Alkaline washing flowback technology has been put forward to reduce the contamination to environment by acidization and fracture cleaning and the damage to gathering pipeline network and rod-tubing pump by residual acid, and good economic benefit has been obtained. The successful research in this paper provides a reliable basis for oil increase measures in low permeability oilfield and has high economic benefit.