DEVELOPMENT OF AN INNOVATIVE METHOD FOR INCREASING OIL RECOVERY OF CLAY LAYERS

Consideration has been given to intensifying the process of oil production using a new innovative method of enhancing oil recovery of mudded-off formations in Azerbaijan whose purpose is a reduction and sometimes full prevention of the phenomenon of swelling of clay fractions contained in the composition of oil reservoirs in the process of implementing local fl ooding. In laboratory investigations, electrochemically treated water, catholyte, was used as a displacing fl uid. It was established that the curves constructed for formation waters treated with alkaline solution (i.e., chemically) and catholyte (i.e., electrochemically) are similar, which confi rms yet another time that they create an identical alkaline medium. In both cases, due to the rise in the pH value, we observed a signifi cant drop in the interfacial tension on the "water–oil" contact line. However, the tension occurring on the contact boundary of the considered "activated water–oil" pair decreases faster with respect to the interfacial tension formed between oil and chemically treated water. The analysis of the dynamics of the increase in the recovery factor in the reservoir model after exposure to chemically and electrochemically treated water has shown that when the reservoir is exposed to catholyte, this indicator rises much faster. A study has been made of the infl uence of the reservoir model of electrochemically treated water on oil permeability. As a result of a more favorable dispergation of activated water into oil as an emulsifi er, an indirect confi rmation of the appearance of an emulsion in reservoir conditions was obtained. The existence of this fact massively increases the likehood of an emulsion appearing in reservoir conditions and enhances the range of emulsions emerging as a slug in the process of displacing reservoir fl uids. Thus, the injection of the proposed electrochemically activated fl uid into the formation with a view to maintaining formation pressure and reducing the swelling factors of formation rocks is real and expedient.
   
Author:  N. M. Safarov
Keywords:  intensifi cation of production, reagent-free method, electrochemical activation of water, potential determining ions, clay minerals, swelling, increasing the oil recovery factor, possibility of emulsion occurrence in a formation
Page:  1056