Device and method for horizontal gas well to drain liquid and produce gas

Abstract

The invention relates to a device and a method for a horizontal gas well to drain liquid and produce gas. The device disclosed by the invention mainly comprises a drainage fine tube, an upper oil tube, a ground gas injection tube, a sleeve, a cut-off device, a special joint, a lower oil tube, a packer, a ground controller, a cable, a guide wire, a gas lifting valve, an electric pump unit, and an underground liquid indicator, wherein the packer is used for separating oil sleeve annuluses at the vertical section and the horizontal section; the cut-off device comprises an outer barrel and a throttle part; the gas lifting valve is arranged on the lower part of the drainage fine tube, so as to form a gas lifting drainage channel with the ground gas injection tube; and the electric pump set is connected with the ground controller by the cable. The method disclosed by the invention comprises blocking a reflux liquid and improving gas flow velocity; the underground liquid indicator is used for real-timely recording liquid level data and transmitting the liquid level data to the ground controller; the ground controller is used for intelligently controlling the working condition of the electric pump set according to the height of the liquid level, or pouring gas to the oil sleeve annulus through the ground gas injection tube. According to the device and the method disclosed by the invention, the liquid energy of stratum gas is sufficiently utilized.

Description

technical field [0001] The invention relates to a device and method for liquid drainage and gas recovery of horizontal gas wells, belonging to the field of petroleum and natural gas exploitation. Background technique [0002] Horizontal well technology for gas reservoirs can increase the contact area between the wellbore and the gas reservoir, and improve the production degree of the gas reservoir, so it is becoming more and more popular in the development of gas reservoirs in my country. However, when the horizontal well mining enters the middle and late stages, the energy of the formation will decline, and there will be fluid accumulation at the bottom of the well, which will cause the gas well to reduce production or even stop production due to "water flooding". How to implement liquid drainage and gas recovery has become the key to ensuring stable production of horizontal gas wells. [0003] At present, there is a common problem in the conventional liquid drainage and ga...

AI Technical Summary

Problems solved by technology

However, the current liquid drainage and gas recovery process allows the liquid to flow back to the bottom of the well to form fluid accumulation before the liquid is drained, which not only loses the original gravitational potential energy of the lifted liquid, but also reduces the gas production due to the increase in formation back pressure, and loses the formation liquid-carrying energy of gas

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