System and method for enhanced oil recovery utilizing alternating stacked liquid and gas slugs

A system for conducting enhanced oil recovery comprising:

• a buffer tank including:
• a liquid inlet through which liquid is received from a liquids source into the buffer tank;
• a gas inlet through which gas is received from a pressured gas source into the buffer tank;
• a gas outlet in fluid communication with gas reservoired in the buffer tank;
• and
• a liquid outlet in fluid communication with liquid reservoired in the buffer tank;
• a pressure control configured to maintain a specified pressure in gas reservoired within the buffer tank, and wherein the pressured gas reservoired within the buffer tank exerts a corresponding pressure on liquid reservoired within the buffer tank;
• and
• a mixer in fluid communication with the gas outlet and the liquid outlet, the mixer being controlled to deliver alternating slugs of gas and liquid to a subterranean wellhead and thereby establishing a plurality of stacked, alternating slugs of gas and liquid travelling downhole into a subterranean well;
• and
• the mixer being further configured to provide a mixed-phase injection through a mixed-phase injection mode;
• and
• a mixed-phase meter configured to measure a flow rate of the liquid slug, the gas slug, and/or a mixed-phase slug.