Liquid foaming agent injection method

Abstract

The invention relates to a liquid foaming agent injection method, belonging to the field of natural gas exploitation. The method comprises the following steps: (1) mounting a packer at a pipe shoe of an oil pipe to separate the oil sleeve annulus and the well bottom; (2) mounting a short coupling on the upper part of the packer, wherein the side surface of the short coupling is provided with a foaming agent channel which communicates the oil sleeve annulus with the lower part of the short coupling, and the lower part of the short coupling is connected with capillaries and communicated to an accumulated liquid on the middle lower part of the well bottom all along; (3) injecting the foaming agent from a well mouth oil sleeve annulus gate to the oil sleeve annulus, wherein the foaming agent resides and gathers at the oil sleeve annulus on the upper part of the packer, and enters the accumulated liquid through the foaming agent channel of the short coupling and the capillaries on the lower part; and (4) mixing natural gas and the foaming agent solution, wherein the mixture passes through a torsional porous plate at the center of the short coupling, enters the oil pipe on the upper part, and is finally discharged. The invention enhances the utilization ratio of the foaming agent, the mixing degree of the foaming agent with the well bottom accumulated liquid, and the foaming efficiency, reduces the use amount of capillaries, and lowers the cost.

Description

technical field [0001] The invention relates to a foam drainage gas recovery technology in the field of natural gas exploitation, in particular to a method for injecting a liquid foaming agent. Background technique [0002] In natural gas exploitation, after water is released from gas reservoirs, liquid accumulation will gradually form at the bottom of the well, seriously affecting the production capacity of natural gas. Foam drainage gas recovery technology is to add a foaming agent into the wellbore to make the natural gas and bottom-hole fluid to form foam, and use the foam to discharge the wellbore fluid, so that the gas well can resume production and prolong the production period, so as to improve the final recovery of the gas reservoir rate purposes. The foaming agent is generally selected from the existing commercially available foaming agents according to the properties and temperature of the gas well fluid. For specific methods and standards, please refer to the pe...

AI Technical Summary

Problems solved by technology

The advantage of this method is: the foaming agent can be well injected into the bottom of the well to better mix with the bottom fluid, improving the utilization rate of the foaming agent and the drainage effect; the disadvantage is that the amount of capillary used is large, resulting in cost too high

[0003] Therefore, in order to solve the above two injection methods, although they have their own advantages, their shortcomings are also relatively obvious, and their use is subject to certain restrictions.

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