Ultralow interface tension coupling type air-foam oil displacement method

Abstract

The invention relates to an ultralow interface tension coupling type air-foam oil displacement method. The method comprises the following steps of: mixing air and a foaming agent on the ground, then injecting a mixture into an oil layer to generate air-foam liquid in the oil layer; injecting strong air foam liquid GFPA (Glass-Fiber Reinforced Nylon) in a first step to generate highly strong percolation resistance in a high-percolation water channeling passage so as to force an ultralow interface tension air-foam system ODS ( Oil Displacement System), subsequently injected in a second step, to enter a low-percolation layer, wherein the ODS is defoamed while meeting oil in the low-percolation layer and reduces the percolation resistance, the oil-water interface tension is ultralow, and the oil displacement efficiency is high; and subsequently, alternatively injecting the GFPA and the ODS. The ultralow interface tension coupling type air-foam oil displacement method disclosed by the invention is mainly suitable for increasing the recovery ratio of high-water-content old oil field in the later stage of development.

Description

technical field

[0001] The invention relates to an oil displacement method for enhancing crude oil recovery in the tertiary oil recovery technology. Background technique

[0002] With the rapid development of the global economy, human demand for oil is also increasing. At present, due to the bottleneck of exploration technology, the discovery of new blocks is becoming more and more difficult, so more and more tertiary oil recovery technologies are applied to old oil fields to ensure the stable production of oil fields. Among the tertiary oil recovery technologies in mature oilfields of continental sedimentary reservoirs in China, chemical flooding is the fastest-growing method, among which polymer flooding and composite flooding have been widely used in the development of various oilfields and achieved good results. Due to the limitations of polymer flooding and composite flooding technologies in double-high oil reservoirs with complex fault blocks, researchers proposed a n...

Examples

Embodiment 1

[0033] Example 1: Extreme water flooding double-pipe parallel core experiment

[0034] A group of double-pipe parallel cores (saturated with oil) were connected to the water flooding experiment process (the temperature has been kept at the reservoir temperature), and the water flooding experiment was carried out at a water flooding speed of 5m / d. %), continue water flooding for 5PV, and end the experiment when the outlet no longer produces oil. During the displacement process, record the pressure change value, water cut and recovery degree change at every 0.1PV interval, and calculate the ultimate recovery. For details, see attached figure 1 .

Embodiment 2

[0035] Example 2: Air flooding double-pipe parallel core experiment

[0036] A group of double-pipe parallel cores were connected to the water flooding experimental process (the temperature has been kept at the reservoir temperature), and the water flooding was carried out at a water flooding speed of 5m / d. The air mass flowmeter controls the volume under injection pressure) 4PV, and then the subsequent water flooding 1PV to end the experiment; during the displacement process, the displacement speed of air is consistent with the displacement speed of water displacement, and the pressure change value is recorded every 0.1PV interval , water cut and recovery degree changes, and calculate the ultimate recovery rate, see the attached figure 2 .

Embodiment 3

[0037] Example 3: Pure foaming agent (surfactant) flooding double-pipe parallel core experiment

[0038]Connect a group of double-pipe parallel cores into the water flooding experimental process (the temperature has been kept at the reservoir temperature), and carry out water flooding at a water flooding speed of 5m / d. The prepared surfactant solution displaces 4PV, followed by water flooding for 1PV to end the experiment; during the displacement process, the displacement speed of air is consistent with that of water displacement, and the pressure change, water content and Changes in recovery degree, calculation of ultimate recovery, see attached image 3 .

technical field

[0001] The invention relates to an oil displacement method for enhancing crude oil recovery in the tertiary oil recovery technology. Background technique

[0002] With the rapid development of the global economy, human demand for oil is also increasing. At present, due to the bottleneck of exploration technology, the discovery of new blocks is becoming more and more difficult, so more and more tertiary oil recovery technologies are applied to old oil fields to ensure the stable production of oil fields. Among the tertiary oil recovery technologies in mature oilfields of continental sedimentary reservoirs in China, chemical flooding is the fastest-growing method, among which polymer flooding and composite flooding have been widely used in the development of various oilfields and achieved good results. Due to the limitations of polymer flooding and composite flooding technologies in double-high oil reservoirs with complex fault blocks, researchers proposed a n...

Examples

Embodiment 1

[0033] Example 1: Extreme water flooding double-pipe parallel core experiment

[0034] A group of double-pipe parallel cores (saturated with oil) were connected to the water flooding experiment process (the temperature has been kept at the reservoir temperature), and the water flooding experiment was carried out at a water flooding speed of 5m / d. %), continue water flooding for 5PV, and end the experiment when the outlet no longer produces oil. During the displacement process, record the pressure change value, water cut and recovery degree change at every 0.1PV interval, and calculate the ultimate recovery. For details, see attached figure 1 .

Embodiment 2

[0035] Example 2: Air flooding double-pipe parallel core experiment

[0036] A group of double-pipe parallel cores were connected to the water flooding experimental process (the temperature has been kept at the reservoir temperature), and the water flooding was carried out at a water flooding speed of 5m / d. The air mass flowmeter controls the volume under injection pressure) 4PV, and then the subsequent water flooding 1PV to end the experiment; during the displacement process, the displacement speed of air is consistent with the displacement speed of water displacement, and the pressure change value is recorded every 0.1PV interval , water cut and recovery degree changes, and calculate the ultimate recovery rate, see the attached figure 2 .

Embodiment 3

[0037] Example 3: Pure foaming agent (surfactant) flooding double-pipe parallel core experiment

[0038]Connect a group of double-pipe parallel cores into the water flooding experimental process (the temperature has been kept at the reservoir temperature), and carry out water flooding at a water flooding speed of 5m / d. The prepared surfactant solution displaces 4PV, followed by water flooding for 1PV to end the experiment; during the displacement process, the displacement speed of air is consistent with that of water displacement, and the pressure change, water content and Changes in recovery degree, calculation of ultimate recovery, see attached image 3 .

Images