Concentric exhaust gas-mixed dilution oil production string for fire-flooding effective wells

Abstract

The invention provides a concentric type exhausting and blending-light oil production pipe string of a fire flooding effect reception well. The concentric type exhausting and blending-light oil production pipe string of the fire flooding effect reception well comprises an inner pipe string and an outer pipe string which are concentrically sleeved outside and respectively suspended on wellhead equipment, wherein the inner pipe string comprises a first oil pipe and an oil-well pump which is arranged under the first oil pipe and the outer pipe string is sequentially provided with and connected with a second oil pipe, an exhausting and blending-light packer, a third oil pipe and a gas anchor from top to bottom. According to a special structure design of an exhaust and thin-oil blending packer, thin oil can be blended inside from annulus of an oil casing, flows under the oil-well pump through a longitudinal channel of a crossing bridge type channel inside a packer and is mixed with crude oil to achieve light blending, viscosity decreasing and lifting effects and bottom hole gas floats upward to the lower portion of the packer simultaneously through separation of the gas anchor, enters into the annulus between the inner pipe string and the outer pipe string through a transverse channel of the crossing bridge type channel and is discharged out of a well through the wellhead equipment finally. The concentric type exhausting and blending-light oil production pipe string of the fire flooding effect reception well has the advantages of guaranteeing the normal operation of the fire flooding effect reception well; not only effectively solving the thin-oil blending problem but also avoiding the oil well casing damage from residual gas.

Description

technical field [0001] The invention relates to the fire-burning oil layer technology in the field of heavy oil thermal recovery, in particular to a concentric exhaust-mixed-lean oil recovery production string of a fire-driven effective well. Background technique [0002] Due to the high content of colloid and asphalt and poor fluidity of heavy oil in Liaohe Oilfield, it is difficult to exploit, so steam stimulation is often used for development; however, with the increase of steam stimulation rounds, the effect of steam stimulation in the later stage is not good, so the current In the Liaohe Oilfield Gaosheng Oil Production Plant, the fire flooding technology is used as the production method. [0003] After a large amount of compressed air is injected into the fire flooding steam injection well, it is burned downhole, and the heat released after combustion heats the heavy oil, driving the crude oil into the fire flooding production well, and then lifting production. Howeve...

AI Technical Summary

Problems solved by technology

However, with the increase of residual gas after combustion, most of the gas is discharged into the production well, resulting in an increase in the bottom-hole steam volume of the affected production well, and the daily exhaust volume reaches 2000030000m 3

As a result, the viscosity reduction method of blending thin oil from the oil casing to empty can not be carried out, resulting in the failure of normal production of the production well

In addition, the gas after combustion contains a large amount of CO, CO 2 , NO, NO 2 and N 2 These gases seriously corrode the casing under high temperature and high pressure, which greatly reduces the service life of the oil well.

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