Preflush
Stimulation treatment contains multiple fluids that are pumped in sequence to achieve the best results. Preflush is the fluid stage that is pumped before the main treatment. Preflush is used for dissolving calcareous materials, rust, or displacing brine before the main treatment fluid comes in contact with the formation. The presence of these materials could cause the plugging of formation pores when coming in contact with the main treatment fluid. The composition is decided based on the type of reservoir rock and formation damage.