Salt cavern building method based on opposite-well mining type old wells and application thereof

Abstract

The invention relates to a salt cavern building method based on opposite-well mining type old wells and an application thereof, and belongs to the technical field of salt mining. The salt cavern building method comprises the following steps that (1) detection and checking are conducted on the opposite-well mining type old wells; (2) a well is drilled between the two old wells and extends to a rock salt layer; (3) pipes are downwards put, specifically, a casing pipe and a center pipe are downwards put into the drilled well, and the center pipe is sleeved with the casing pipe; (4) oil is injected between the casing pipe and the center pipe; (5) fresh water is injected from the center pipe and reaches the old wells on the two sides through old well horizontal sections to dissolve rock salt into bittern, and the bittern is discharged from the old wells on the two sides; and (6) when a cavern reaches the set volume, injection of the fresh water is stopped, and building is finished. The salt cavern building method based on the opposite-well mining type old wells achieves the comprehensive targets of horizontal section plug removal, salt mining and oil and gas storage and is suitable for being widely applied and popularized.

Description

technical field [0001] The invention relates to a method for constructing a salt karst cave based on an old well mining type and its application, and belongs to the technical field of salt mine mining. Background technique [0002] The development of salt resources plays an important role in the country's economic activities. The development methods of salt are roughly divided into three types: deep well mining, water-soluble mining and solar evaporation. In deep well mining, the shaft is first connected to the bottom of the mine, and then the checkerboard-shaped compartments are built between the shafts by drilling, excavation, blasting, etc., and finally the mined large salt mines are crushed and transported to the ground by the conveyor belt; Water soluble mining is to first inject water into the well to dissolve the salt, and then pump the salt solution up and transport it to the processing plant for dehydration treatment; solar evaporation is to extract the salt from se...

AI Technical Summary

Problems solved by technology

[0004] In my country, there are a large number of saddle-shaped old wells left over by the way of well mining. These saddle-shaped old wells have a long horizontal section, and when they are dissolved, they are often exploited without oil pads. The horizontal section is difficult to effectively dissolve, the size is small, and even blocked. (Although it is blocked, water can flow through the pores of the molten slag), and cannot continue to be mined and cannot meet the needs of oil and gas storage. At the same time, the dissolution mainly occurs above the two wellheads, which may easily cause accidents such as roof leakage, and is difficult to use As a National Energy Strategic Reservoir

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