Thick oil huff and puff deep channel blocking system and injection method thereof

Abstract

The invention provides a thick oil huff and puff deep channel blocking system and an injection method thereof. Solidification channel blocking agent composed of sodium and soil aqueous solution with the mass fraction of 4.0% to 6.0% and cement slurry with the mass fraction of 4.0% to 6.0% is adopted in a near wellbore zone, wherein the volume ratio of the two solutions is (0.8 to 1.2) : 1; temperature resistance supermolecule channel blocking agent composed of HPAM (polyacrylamide) aqueous solution with the mass fraction of 4.0% to 6.0% and phenolic resin aqueous solution with the mass fraction of 1.0% to 1.4% is adopted in a transition zone, wherein the volume ratio of the two solutions is (0.8 to 1.2) : 1; and temperature sensitive polymer aqueous solution with the mass fraction of 2.0%to 4.0% is taken as thermal thixotropic channel blocking agent in a far wellbore zone. According to the invention, steam channeling of large porous channels is blocked with the solidification channelblocking agent and the temperature resistance supermolecule channel blocking agent, and steam channeling generated by fine slits is blocked with the thermal thixotropic channel blocking agent, so that the purpose of deep channel blocking is achieved through combined blocking of the blocking agents.

Description

Technical field: [0001] The invention relates to a technology for further enhancing crude oil recovery in the technical field of oil and gas field development engineering, in particular adopting a deep channeling system to improve the swept volume of steam in a steam huff and puff well, thereby enhancing crude oil recovery. technical background: [0002] During the process of steam huff and puff, due to the influence of unfavorable factors such as heterogeneity of the oil layer, high density difference between steam and heavy oil, and high mobility ratio, steam overlay and steam fingering occur in the oil layer, resulting in a gap between wells and wells. Steam channeling occurs. Steam channeling makes the vertical suction section of the oil layer uneven, and the steam advances unevenly in the horizontal direction, so that the swept volume of the steam becomes smaller, thereby reducing the recovery rate of heavy oil thermal recovery and increasing energy consumption. Using ...

AI Technical Summary

Problems solved by technology

At present, the commonly used inorganic particles are difficult to enter the deep part of the formation, the plugging distance is short, and the steam continues to point after the bypass flow, and there are still small gaps after the plugging, and the steam with relatively high mobility can still flow, and the sealing effect is poor

The stability of the foam plugging agent is poor, and its sealing effect is not good