Research on performance of DZD efficient two-phase dispersed flushing fluid

Improve the compatibility of two interfaces in the three liquid of drilling fluid-flushing fluid-cement slurry,reduce the damage of flocculation and structure to each other,effectively improve slurry properties on the mud displacement efficiency and the interface cementation strength,ensure good cementing quality. Through a large number of indoor study,a highly efficient bipolar dispersant was optimized,flushing fluid formula was determined. The performance evaluation results show that the flushing fluid has good rheological property,and good compatibility dispersion with low solid drilling fluid and cement slurry; the efficiency low solid mud flushing reached more than 90%,the interface cementation strength increased by more than 50% on average. In addition,based on the micro analysis,the cause of cementation strength increasing was analyzed by scanning electron microscope( SEM) and atomic force microscope( AFM).