Double well construction method for salt cavern gas storage

Abstract

The invention discloses a salt-cavern gas storage twin-well building method, and belongs to the technical field of technology for building salt-cavern gas storages. The salt-cavern gas storage twin-well building method comprises the steps of: first, respectively drilling a first well and a second well, wherein the distance between the center lines of the first and second wells is 15m-30m; second, communicating the first and second wells through a natural dissolution method, and circularly building cavities for the first and second wells; third, injecting gas into the first well, discharging brine water from the second well; fourth, performing gas injection and recovery to the first or second well, or simultaneously performing gas injection and recovery to the first and second wells. According to the salt-cavern gas storage twin-well building method, respectively through injecting water into the first well and discharging brine water from the second well, the water injection volume is increased, the cavity building speed is enhanced, and the storage building period is shortened; respectively performing solution mining to the cavities of first and second wells by a single well convection method, the storage is built by fully utilizing salt beds, the dissolution volume of the cavity is enlarged, the cavity form and stability are ensured, and thus the gas storage is ensured to operate safely.

Description

technical field [0001] The invention relates to the technical field of salt-cavern underground gas storage construction, in particular to a double-well construction method for a salt-cavern gas storage. Background technique [0002] Most of the salt-cavern gas storages in my country are built on layered salt layers, with low-grade salt rocks and many interlayers. The single-well convection method is mostly used for cavity construction, and the cavity construction speed is slow. It takes about 4 years, can not meet the needs of my country's underground gas storage construction. [0003] Salt cavern gas storage has a history of more than 50 years in foreign countries. In order to speed up the dissolution rate of salt caverns, foreign countries have developed and used a variety of solubilization tools and techniques, such as the use of fluid dynamics conversion cavity construction, jet countercurrent hydraulic Install cavity-making and other promoting tools and technological me...

AI Technical Summary

Problems solved by technology

However, foreign countries build reservoirs for salt mounds. Compared with domestic stratified salt reservoirs, the salt rocks are of high grade, thick salt layers and less interlayers. The new techniques and methods for foreign salt caverns are difficult to adapt to domestic stratified salt reservoirs.

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