Sand-control techniques with sol-gel MgO nanometer material

Migration of fine grains in reservoir formations with high clay and siltstone contents may plug, erode, and damage sand barriers, and cause significant reduction of fluid productivity. Absorption efficiency of various nanometer materials have been reviewed by using relevant test data and calculation results to pick out the sol-gel MgO nanometer material as coated proppant in gravel-packing layers. With absorption efficiency of 78.85% for fine grains, turbidity of its outflow fluid is only 5.5% of that obtained by using cationic sand control agent, and sand content in its out-flow fluid is only approximately 9.3% of that contained in fluid out of cationic sand control agents, which suggests its sand consolidating performance is far better than conventional cationic sand control agents currently used in oilfields. After it was applied in Well LNJ501 of the Shengli Oilfield, sand content of the produced fluid was less than 0.01%, and the fluid productivity of the well was 3.42 times of that before the treatment, and effective production time of the well was 389 d, which indicates the sol-gel MgO nanometer material can effectively enhance fluid productivity and extend effective sand control period.