Specifically, the importance of returning to the mining body in time is as follows: (1) The ore content of the pillars accounts for about 20-50% of the ore mass, which is a considerable amount. If it is not timely recovered, it will lose state resources. Earthquake disasters not only lead to human accidents. Often, the resources of several stages will be lost, so that they cannot be produced at all (and they cannot be collected). (2) When the mining work has been reduced several stages, returning to the upper stage and returning to the mining column often destroys the normal top-down stage of recovery, which is unfavorable for the entire production. (3) If the mining column is not returned in time, the service life of each stage will be invisibly enhanced, and the roadway, equipment and pipelines will be maintained, which will inevitably increase the maintenance cost. (4) Failure to return to the mining column in time will inevitably result in multi-stage decentralized operations, which will diversify the management of several major process systems (injection and transportation, ventilation, drainage, power supply, gas supply, water supply, etc.) and increase the number of auxiliary staff. And the efficiency of the equipment is not well utilized. (5) Due to the failure to return to the mining column in time, the mining project originally done in the pillar is often destroyed. When returning to the mining column, it is necessary to re-add the mining lane, which will result in waste of the mining project and ground pressure. Management difficulties. (6) Failure to return to the mining column in time, resulting in multi-stage production, the ventilation conditions will be deteriorated. (7) Failure to return to the mining column in time will result in a disproportionate proportion of the third-grade ore, or arrears, and will not guarantee the balance of mine production. In summary, it can be seen that while returning to the mining room, it should be planned to return to the mining column in time. When designing the mining room, the pillar recovery should be designed at the same time. For example, mines such as the Dajishan tungsten mine are doing a good job in this regard.
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The importance of pillar mining
The pillar plays a supporting role for the surrounding rock and is used to control the ground pressure. At the same time, the pillar also plays a role in protecting the mining roadway and isolating the upper or surrounding waste rock, thereby ensuring ore loss and depletion during the mining process. In order to ensure that mining mining can achieve better technical and economic indicators.