For the oil-wet solid surface,the contact angle between oil and solid surface under the action of surfactant would reduce to form oil drips,which was further lengthened and broken.

• 当在原油中加入表面活性剂溶液后,油-水界面张力迅速降低,在亲油固体表面上,界面张力降低到一定程度后,原油与固体的接触角变小,形成油珠,并且油珠被不断拉长直至拉断。