Research and application of multifunctional flushing fluid

In the process of oilfield development, the reservoir of oil wells were polluted due to well flushing and pump inspection, which resulted in long recovery period of oil well production after operation, or even difficult recovery of production. According to the states mentioned above, researchers developed XST and XSK series multifunctional flushing fluid, which had the function of anti-swelling, anti-pollution, as well as cleaning functions. The laboratory experiments showed that the oil washing efficiency ≥80%, anti-swelling rate ≥70%, as well as the damage value of reservoir permeability ≤30%. The above formula was applied in J902 oil well, which achieved great success. Not only the fishing tools went in smoothly, but also the recovery period after the well flushing operation was shortened to 4 days, which effectively reduced the impact of the well flushing operation on the well production.