Semi-closed underground brine mining system and construction method thereof

Abstract

The invention relates to a semi-closed underground brine mining system and a construction method thereof. The semi-closed underground brine mining system comprises a gas pressing device, a first waterresisting layer, a second water resisting layer, a brine storage layer positioned between the first water resisting layer and the second water resisting layer, a partition wall and brine collecting channels. The upper end of the partition wall extends to the first water resisting layer, and the lower end extends to the second water resisting layer; and the brine storage layer is divided into multiple closed spaces by the partition wall, the first water resisting layer and the second water resisting layer. The brine collecting channels and brine outlets are excavated in a top salt rock layersof the closed spaces; the closed spaces are horizontally penetrated by the brine collecting channels to form semi-closed spaces; and the semi-closed spaces are brine collecting blocks. A gas pressingwell is arranged in each brine collecting block; brine outlets are excavated in the opening sides of the brine collecting blocks; and the brine outlets penetrate to the brine storage layer, and communicate the brine storage layer with the brine collecting channels. The semi-closed underground brine mining system can reduce the brine collecting cost, greatly improves the brine collecting amount, improves the mining efficiency, and improves the recovery rate.

Description

technical field [0001] The application relates to the technical field of underground brine mining, in particular to a semi-closed underground brine mining system and a construction method thereof. Background technique [0002] Potassium salt is mainly divided into two categories, one is solid potassium salt, which is mainly distributed in Canada, Russia, Belarus, Thailand, Laos and other countries, and only a small amount is distributed in Jiangcheng, Yunnan Province in my country; the other is liquid brine mine, which is mainly distributed in Among the salt lakes in arid and semi-arid areas, my country is mainly distributed in the salt lakes in Qinghai, Xinjiang, Tibet and other regions in the west of China; potassium salt resources are my country's strategic resources, and potassium salts are mainly used to produce potash fertilizers for agricultural production and are food grains. [0003] China is the largest potash fertilizer consumer in the world, and potash is one of t...

AI Technical Summary

Problems solved by technology

China's geological reserves of KCl are about 990 million tons, and liquid brine mines are the mainstay. The production of potassium salts is mainly through the collection of underground brine in salt lakes to produce potassium fertilizers. With the extension of the development period of salt lakes, the increase in development intensity and production volume At present, most of the surface brine of the salt lake is seriously insufficient, and the brine of the surface salt layer of the salt lake can no longer maintain normal production, so that the service life of the salt lake resources is constantly shortening, and the service life of the salt lake resources in my country is less than 30 years

The third is the method of brine extraction combined with wells and canals. At present, most of the salt lakes adopt the method of brine extraction from the deep brine storage layer below the surface salt rock layer of the salt lake, because only a single channel or well mining cannot meet the actual production. It is not the best and most economical way; due to the low porosity, slow flow rate and small range of brine mining in the deep brine storage layer below the surface salt rock layer of the salt lake, and the high cost of brine mining canal excavation, the combined layout and construction is relatively simple Brine extraction wells can be arranged in areas where the brine extraction canals are difficult to extend, which can make up for the shortage of brine extraction; but for the deep brine storage layer below the surface salt rock layer of the salt lake with low porosity, low permeability, and low water supply Said that there is still the problem that the amount of brine is too small to meet the actual needs of production

[0006] From the point of view of the existing brine mining technology in the deep brine storage layer below the surface salt rock layer of the salt lake, brine mining is mainly carried out through the combination of wells and canals. The way of collecting brine and extracting brine through man-made or natural brine water level difference in brine extraction canals and brine extraction wells, not only the brine flow rate is slow and the flow rate is small, but also the efficiency of brine extraction is low, the amount of brine extraction is small, and the construction cost is high. Difficult to meet actual production needs

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