At Gangdong oil field,Dagang,the viscosity of polymer AT-420 solution prepared in recycled produced water(RPW) as taken immediately is very low,being of 20 mPa·s at concentration of 40 g/L,a value by six times lower than that in RPW aged in open air over 20 hrs,and increases with RPW ageing time fast in initial 80 min and notably slower later.

Alkaline treatments with corrosion and scaling inhibition of highly corrosive recycled produced water (RPW) of Guangli water treating plant, Dongxing, Shengli, for reservoir flooding are conducted in laboratory experimentally.

The present situation of recycled produced water treatments in Shengli oil fields and the new technologies and techiques introduced in recent two years were described.

According to the characteristics of the Pucheng oil field note well recycle sewage, a kindof new pipeline pickling scale removal technology of water flooding has put forward.

In accordance with the feature of waste water flooding in Fuyu oilfield,the experiments for resistivity of cores under produced water reinjection are carried out.

In 15￣20 days after the produced water reinjection,the water injectivity of the reinjection wells reduced rapidly,because the water quality didn′t meet the reservoir requirements.