Electrochemical method for accelerating dissolution of soluble bridge plug

Abstract

The invention provides an electrochemical method for accelerating dissolution of a soluble bridge plug. The electrochemical method comprises the specific steps that 1, as for the situation that the inner wall of a casing is subjected to internal corrosion prevention, 5-8 m<3> of hydrochloric acid or sulfuric acid with the mass percent being 10-15% is injected at the displacement of 1-2 m<3> / min firstly, then 5-8 m<3> of guanidine gum base liquid is introduced for isolation, and replacing is conducted with clear water to the bridge plug position; as for the situation that the inner wall of thecasing is not subjected to internal corrosion prevention, a saturated strong electrolyte solution is injected at the displacement of 1-2 m<3> / min firstly, then a gas and heat production agent A, guanidine gum base liquid and a gas and heat production agent B are pumped sequentially, and replacing is conducted with clear water to the bridge plug position. Through the method of electrochemistry (a primary battery and an electrolytic cell), the potential difference of various metals is utilized, by giving a certain current to the casing, a soluble ball and the soluble bridge plug are rapidly dissolved, the diameter of a wellbore is recovered in time, and the electrochemical method is of great practical significance for rapid production or rapid fracturing construction of the next section.

Description

technical field [0001] The invention relates to the field of petroleum exploitation, in particular to an electrochemical method for accelerating the dissolution of a soluble bridge plug. Background technique [0002] In recent years, hydraulic pumping rapid drilling bridge plug volume fracturing technology has been widely used in the development of shale gas and tight oil in North America, and it is the main stimulation technology for horizontal wells in tight reservoirs abroad. This process has the characteristics of high operating efficiency, large displacement injection for volume fracturing, and multi-cluster perforation. As an emerging horizontal well stimulation technology, it has been widely used in the development of foreign shale gas reservoirs and tight gas reservoirs in recent years. . In order to reduce the drilling and grinding time of bridge plugs and save the cost of grinding and milling, some companies have developed fracturing bridge plugs made of soluble m...

AI Technical Summary

Problems solved by technology

In the actual construction process of the oil field, it was found that after the fracturing was completed, when it was necessary to put into production quickly, it was found that some bridge plugs were still undissolved and still needed drilling and grinding, which affected the time to get oil on site

In special circumstances such as sand blockage, when it is necessary to speed up the dissolution of the bridge plug, there is often no way to do anything but wait for the bridge plug to dissolve itself, usually 2-3 days, which affects the construction progress

[0003] In order to overcome the existing problem of not being able to quickly dissolve bridge plugs and waiting too long for bridge plugs to dissolve and affecting construction progress, the present invention provides an electrochemical method for accelerating the dissolution of soluble bridge plugs. The present invention uses electrochemical (primary battery and electrolytic Pool) method, using the potential difference of various metals, by giving a certain current on the casing, quickly dissolving soluble balls and soluble bridge plugs, and restoring the wellbore diameter in time, no matter for rapid production or rapid fracturing Construction has very important practical significance

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