According to the reservoir features of the lower member of V Stratum in Shuanghe Oilfield,a heterogeneous model was established,and remaining oil distribution pattern of different models was obtained.The effects of different geological and development conditions on remaining oil distribution were analyzed.Through regression analysis,the correlation of recovery percent,remaining oil heterogeneity degree and other factors(such as fluid extracting rate,well spacing,plane permeability ratio,formation dip angle and reservoir thickness) could be acquired when the composite water cut reached 95% in production well in the flooding pattern.A regression equation and numerical simulation were used respectively to calculate the recovery percent and remaining oil heterogeneity degree of five-spot pattern in Shuanghe Oilfield.The errors of these two methods are less than 10%.The integrated application of regression equation is significance for describing the remaining oil and its distribution pattern quantitatively,it provides a guidance for future adjustment in flooding pattern of oilfields.

The oily sludge from the Fourth Plant of Daqing Oilfield was solidified by directly adding coagulation ac- celerators.The environmental safety of the solidified oily sludge was evaluated.The result showed that compressive strength of the solidified sludge was 4.23 MPa when the mass fraction of coagulation accelerator B was 10% .All the parameters of the solidified sludge lixivium met the national standard of sewage integrated discharge and the solidi- fied sludge could be landfilled safely.