Laboratory Evaluation Of The Performance Of Attapulgite Stabilized Foam System

Foam fluid play an important role in the petroleum industry.Because of its thermodynamic instability,how to improve its stability is the basis and prerequisite for its application.The development of new foam stabilizers is of great significance for improving the stability of foam systems and the wide application of foam in oil displacement.Attapulgite has excellent physical and chemical properties.Natural one-dimensional nanomaterial attapulgite with low production cost obtained by acid purification and surface modification as a foam stabilizer can effectively reduce the application cost of nanomaterial stabilizing foam system,and is of great significance for improving the stability of the foam system.The following work has been carried out and the following results have been achieved:(1)The attapulgite is acid-purified and surface-modified,and then it’s surface morphology,chemical groups,Zeta potential value,mineral composition and dispersibility in different media were analyzed using atomic force microscopy(AFM),infrared spectroscopy,Zeta potentiometer,scanning electron microscope,XRD,and turbidity analyzer.The results show that the natural attapulgite particle is fibrous shaped,its crystal fiber length is about 1μm,and its particle size is between 80 nm and 100 nm,which will obviously clump together in water;the fiber length of the attapulgite crystal before and after the acid treatment was reduced from 1 μm to 0.6 μm,the particle size was reduced from 90 nm to about 40 nm,and the degree of agglomeration in water is weakened.The crystal fiber length of attapulgite before and after surface modification did not change significantly,the particle size increased from 40 nm to 75 nm,and the agglomeration of attapulgite particles after surface modification in water is obviously weakened,and its degree of dispersion is effectively improved.(2)The stabilizing effect and stabilizing mechanism of attapulgite under different treatment conditions on the foam system formed by surfactants(AOS and tetradecylamidine)were studied by airflow method,Waring Blender method and Roche foaming method.The results show that foam drainage half-life of the foam system’s with surface modified attapulgite is largest,followed by that of the foam system with acid puried attapulgite,and that of the foam system with natural attapulgite is least.However,compared with the pure surfactant,the combination of surfactant and attapulgite under different treatments has a better effect on the foam stability,and improve the high temperature resistance and salt resistamce of the foam system to a certain extent.