Study On Properties Of Emulsifying Oil-displacing Agent And Its Influence On Recovery Efficiency

SP flooding is an important research field in enhanced oil recovery.The present results show that the nature of the emulsifier flooding and flooding effects are closely related.In this paper,the properties of emulsifying oil-displacing agent in tertiary recovery and its influence on recovery efficiency are studied.At the same time,a comparative study of other properties of emulsifier(such as interfacial tension,water affinity,adsorption holdup,etc.)is conducted,and its influence on recovery efficiency is also investigated.The emulsifiability of emulsifier will be identified through emulsifying power experiment and emulsion stability experiment.Spectrophotometry is adopted in emulsifying power test.The emulsion machine used in the experiment is researched and developed independently,preparing emulsion and evaluating the emulsifiability of oilfield emulsifier.To simulate the actual reservoir conditions better,the homemade emulsion machine adopts screen design.As for the evaluation methodology,emulsion stability and emulsifying power are considered.Interfacial tension is tested by using Interface Tensiometer.Water affinity is evaluated through the change of rim angle:the smaller the rim angle is,the stronger the water affinity is;the larger the rim angle is.Adsorption holdup is identified according to the amount change of emulsifier before and after the experiment.The experimental results shows that,to regard the emulsion strength composite index as the evaluation coefficient in evaluating displacing property of emulsifier is scientific and reasonable.The higher the emulsion strength composite index is,the higher the oil displacement efficiency is and vice versa.Different levels of Sei,the dialysis recovery was 38.00%to 69.5%and the SP recovery was 8.9%to 25.2%.When the Sei decreases with increasing level,the maximum difference of 102 orders of magnitude difference of 14.3%SP recovery.The higher the oil displacement efficiency is,the recovery efficiency increases as the adsorption holdup increases.