Abstract:
In order to solve the problems of traditional chemical sand control, such as high reservoir damage, low consolidation strength, and short validity period, a water-based nano solution was formed by grafting cross-linking reactive group and hydrophilic group onto the surface of inorganic nano SiO
2 and combining with water-based curing agent, and its performance was evaluated. The results demonstrate that the median particle size of the system is 58 nm, exhibiting excellent consolidation effects for formation sands ranging from 0.05 to 0.85 mm, particularly for fine silty sands. The consolidated sand achieves a strength of 6–12 MPa and a permeability retention rate of 86.19%, meeting the sand control requirements for reservoirs at 40–120 °C. In Shu 3 Area of Liaohe Oilfield, the sand consolidation test applying the water-based nano solution to five wells is carried out. The sand control efficiency reaches 100%, and the liquid production and oil production capacity recover to the pre-sand control level after sand control. The research and field tests show that the water-based nano solution sand consolidation technology has the characteristics of high consolidation strength, low damage to reservoirs, and strong adaptability to various temperatures. It provides an efficient solution for sand control of loose sandstone reservoirs and has significant popularization value.