摘要：The reuse and high viscosity loss rate of polymer-containing wastewater are the key issues to be solved urgently during the development of oil and gas fields. In this study, polysilicon aluminum flocculant (PSiAF) was synthesized in laboratory to investigated the advanced purification of polymer-containing wastewater, and its purification performance and viscosity stability were tested. The main factors affecting polymer solution viscosity, such as pH, ion concentration, salt and suspended solids, were analyzed. In addition, the scaling trend of purified water under stratigraphic conditions was simulated by Oil Scalechem prediction software. The results indicated that the effect of Fe2+, Ca2+, Mg2+, S2- and suspended solids content in solution on the viscosity of the polymer solution was greater than that of the others, and it must be controlled in preparing polymer solution. The optimal dosing formula of the flocculant with the performance of removal of turbidity and calcium was as follows, 50 mg/L polymerized ferrous sulfate (PFS) + 200 mg/L PSiAF + 8 mg/L setting agent. The content of Ca2+, Mg2+ and residual polymer of the purified water, obtained by deepened processing with the flocculant, decreased sharply, and the oil content and suspended solid content was lower, moreover, the purified water hardly contained Fe2+. The average particle size of suspended particles (SS) in purified water was less than 100 nm, which was smaller than the pore diameter or the cores, soformation could not be blocked by SS. As a result, the purified water could be reused for preparing the polymer flooding solution.
