Design method of safe mining water-retaining coal pillar

Abstract

The invention relates to a design method of a safe mining water-retaining coal pillar. The method comprises the following steps: analyzing hydrogeological data; calculating the maximum water flowing fracture height permitted by secondary milling; judging whether the water-retaining coal pillar makes sure safety of a waterproof protecting layer or not, if not, carrying out mining with filling and carrying out back calculation of a filling rate eta; and analyzing safety of a mining fissure seepage to determine that the mining fissure seepage does not penetrate a water-bearing stratum. The methodis simple and accurate, improves the mining upper limit of the water-retaining coal pillar on the premise of ensuring safety production of a working face, improves the coal recovery rate, protects the water source of a mine region, utilizes solid wastes in the mine area reasonably and has a wide application prospect.

Description

technical field [0001] The invention relates to a design method for safely mining a water-retaining coal pillar, in particular to a design method for mining a water-retaining coal pillar by using solid filling. Background technique [0002] With the development of my country's coal mining, the "three under" (under the building, under the road, under the water body) coal pressing problem is becoming more and more prominent. Among them, the coal pressing under the water body accounts for about 25% of the total amount of "three under" coal pressing. In order to prevent water hazards in the upper aquifer of the coal seam, a large number of water-retaining coal pillars need to be left in traditional coal mining to protect the aquifer from being damaged, thereby ensuring the safe production of the working face. Like this, just make a large amount of coal resources remain underground and cannot be recovered, especially high-quality coal resources, resulting in a huge waste of coal ...

AI Technical Summary

Problems solved by technology

In this way, a large amount of coal resources are left underground and cannot be recovered, especially high-quality coal resources, resulting in a huge waste of coal resources

Although some water-retaining coal pillars have been recovered in mining areas such as Huainan, Huaibei, and Yanzhou, the scope for increasing the upper limit of water-retaining coal pillar mining is limited, the recovery efficiency is low, and the risk of water damage is still relatively high

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