Automatic circulation switchers, separate zone water injection system and automatic circulation water injection method

Abstract

The invention discloses an automatic circulation separate zone periodical water injection method of a water injection well. More than two automatic circulation switchers are arranged in a water injection string and in a way of corresponding to each oil layer; in each automatic circulation switcher, a motor for opening or closing an eccentric water distribution valve is connected with a micro processor; the micro processors of the automatic circulation switchers are configured with opening and closing programs respectively; and the automatic circulation switchers automatically and alternately open and close according to a set time sequence to inject water into each oil layer circularly to realize periodical pulse water injection to underground oil layers. The method is simple in operation, reliable in operation and high in success rate, avoids manual control and a manual control factor, which causes errors easily, and improves water injection development effect.

Description

technical field [0001] The invention belongs to the technical field of oil production, and more precisely relates to a layered water injection automatic circulation switch used on a water injection string in a water injection well, a layered water injection system including the layered water injection automatic cycle switch and the device. The cyclic layered periodic automatic water injection method used by the layered water injection system. Background technique [0002] The situation of downhole oil layers in oilfields in eastern my country is relatively complicated, and it has entered the late stage of water flooding development, especially some oil wells have entered the late stage of development with ultra-high water cut. The contradiction between oil layers in oil wells is becoming more and more serious, the comprehensive water cut is constantly rising, and the targets for tapping potential are complex. The increasing difficulty of oilfield exploitation makes it difficu...

AI Technical Summary

Problems solved by technology

[0005] ①. During water injection, due to the large difference in permeability between layers and the large interference between layers, it is difficult to control the water volume of each layer with water nozzles. The pressure difference between layers is large, and there is also the problem of channeling between water injection layers, which cannot achieve the purpose of layered water injection

[0006] ②. For a single water injection layer, the permeability difference in the layer is large, and the injected water rushes along the dominant channel of the high permeability layer, which affects the swept volume of the injected water and increases the difficulty of tapping the remaining oil potential of the medium and low permeability in the layer

[0007] ③. The downhole steel wire fishing test process is greatly affected by well conditions. When the oilfield enters the later stage of water injection development, with the increase of produced water, the amount of sewage reinjection increases. Due to the difficulty of sewage treatment, the water quality of injection water gradually deteriorates, and the machinery in the water High impurity content, serious fouling of the tubing string, and tubing regurgitation and other reasons cause obstruction or jamming in fishing, resulting in rework of operations and affecting the validity period of dispensing

However, this electromagnetic linear adjustment downhole injection-production flow device requires ground staff to control the opening and closing of the water distributor through electromagnetic signals, so the water injection deployment operation is relatively complicated, and human errors are prone to occur, resulting in errors in the layered water injection volume and poor water injection effects.

Images