Method of injecting water into reservoirs with geomechanical stimulation by pressure pulse

Abstract

The present disclosure describes a method of injecting water, whether captured or produced during oil processing, into oil reservoirs with geomechanical stimulation by pressure pulse.

1 . A method of injecting water into oil reservoirs with geomechanical stimulation by pressure pulse, the method comprising:
 reducing reservoir pore pressure in a vicinity of an injection well;   applying a pressure pulse, thereby to induce, in a controlled manner, fractures and plastically mobilized regions in the reservoir rock; and   adjusting flow rate and pressure of the injection well to a regular operating situation.   
     
     
         2 . The method according to  claim 1 , wherein the water injection is performed under high pressure in pulses of relatively short duration, compared to an injection period of the injection well. 
     
     
         3 . The method according to  claim 1 , wherein reduction in the reservoir pore pressure is obtained through total shutting in of the injection well or by reducing the injection flow rate to a pre-established minimum value in cases in which complete shutting in of the well causes operational difficulties for the stationary production unit (SPU). 
     
     
         4 . The method according to  claim 3 , wherein a sufficient drop in pore pressure in the well region is obtained within 1 to 3 hours of shutting in of the injection well. 
     
     
         5 . The method according to  claim 1 , wherein the application of the pressure pulse includes one or more low- or high-pressure pulse based on a specific geomechanical study for the well that assesses the geomechanical risks to the integrity of the cap rock. 
     
     
         6 . The method according to  claim 5 , wherein the high-pressure pulse is applied when the injection pressure is greater than the minimum stress in the reservoir rock. 
     
     
         7 . The method according to  claim 5 , wherein the low-pressure pulse is applied when the injection pressure is limited to the minimum stress in the reservoir rock. 
     
     
         8 . The method according to any one of  claim 1 , wherein the pressure pulse comprises rapid and controlled increase in injection flow rate and pressure for a pre-established period of time. 
     
     
         9 . The method according to  claim 1 , wherein the step of adjusting the injection well to the regular operating situation, the pressure and flow rate are adjusted according to operational restrictions and needs of geomechanical and production management of the reservoir.