Foam as a mobility control agent in enhanced oil recovery is becoming more and more attractive. Recently, ASP foam flooding method was proposed, which was based on the mechanism of both lowering interfacial tension to an ultra-low value (10 -3 mN/m grade) and improving sweep efficiency of displacing fluid. However, the alkali (NaOH or Na 2 CO 3 ) in the ASP system will bring about scaling in the reservoir and pipelines if the formation water contains a large number of divalent cations such as Ca 2+ and Mg 2+ . Therefore，it is necessary to develop a non-alkali foam flooding system to improve oil recovery.A novel ultra-low interfacial tension foam agent is developed by the combination of surfactant and additives to lower oil-water interfacial tension and the addition of polymer to improve foam stability. Firstly, the concentration of surfactant and non-alkali additives used as the foam agent was determined by interfacial tension contour diagram. Then, the molecular weight and concentration of HPAM to enhance foam stability in the reservoir was screened. The foamability of the formula was measured using airflow method. Furthermore, the effects of temperature, salinity and shearing on the interfacial property and foamability were investigated to know the adaptability of this method to different oilfields. The heavy oil displacement experiments showed that the final oil recovery could be improved approximately 23% initial-oil-in place over waterflood recovery for the heterogenous core model of which permeability variation coefficient is 0.65, more than that of alkalinesurfactant-polymer flooding.

Based on the automatic dynamic analysis of mechanical systems software, both rigid and flexible models of the space-swing mechanism for the superpave gyratory compactor are developed. The structural analysis shows that the length and the initial phase of cranks, and the assembling accuracy (coordinates) of some points are very sensitive relative to the waving of compaction angle. Greater rigidity helps stabilize the change of the compaction angles.

Backwashing time is one of the most critical operational parameters for biological filter. In order to investigate the effect of backwashing time on iron, manganese, ammonia and turbidity removal, three backwashing time (5 min, 4 min and 3 min) were adopted. Results showed that the average concentration of total iron, manganese and ammonia in effluent was 0.025 mg/L, 0.007 mg/L, and 0.022 mg/L; 0.012 mg/L, 0.001 mg/L and 0.017 mg/L; 0.013 mg/L, 0.000 mg/L and 0.016 mg/L, respectively, which illustrated varying backwashing time had little influence on the removal efficiency of them. The turbidity in effluent was 0.28 NTU, 0.38 NTU, 0.57 NTU, respectively. The shorter backwashing time, the higher turbidity in effluent. Turbidity was almost completely removed in 0~0.4m of the media. After backwashing, the turbidity in effluent was decreased to less than 1 NTU in 40 min, droped to less than 0.5 NTU in 90 min.