Filling the top and bottom columns of the mining house

The top and bottom columns of the filling mine are more difficult to recover than the inter-column. The reasons are as follows: (1) The bottom column is weakened by the mining roadway, the recovery is not safe enough, the depletion and the loss are high; (2) the upper and lower mine houses have been filled, for the return The top and bottom columns with a small amount of mining sometimes need to be excavated into mines, filling and other roadways. Not only the cutting work is large, but also it may be difficult to construct and support. There are not many effective methods for mining the top and bottom columns, and it is one of the weakest and most urgently needed to strengthen the research in the whole mining process.
The mining method and effect of the top and bottom columns are related to the stability of the ore, the distribution of the existing roadway, the filling method and quality of the mine in the previous stage. The empty field method, the filling method, and the caving method can all be used to recover the top and bottom columns, but the filling method is the most used. Table 1 shows the actual data of some mining mines.
Table 1 Brief introduction of some mining mines filling the top and bottom columns of mining houses
mine
(section)
Ore stability
Mining method and
Empty area
Top column height
(m)
Bottom column height
(m)
Top and bottom columns
Mining method
Main index of mining pillar mining
Remarks
On the plate
Lower plate
ore
Recovery rate
(%)
Depletion rate
(%)
Nugget
Productivity
(t/d)
Working face worker
Labor productivity
(ton / work class)
Huangshaping lead zinc ore
More stable
stable
More stable
Dry filling method, the bottom of the bottom has a 0.4-0.5m thick reinforced concrete floor
6
Top column with top layer filling method, bottom column with room column method
91.2
12.2
60
6
Has recovered more than 300,000 tons of ore, the effect is better
Shiju child copper mine
stable
stable
stable
Retaining method, post-harvest water sand filling
4.5
3
Upward horizontal layered dry filling method
83
6.45
5~7
Yangjiazhangzi Molybdenum Mine (Lingqian Mine)
Upward layered dry filling method
4
5
Upward stratified approach dry filling
85～90
8~10
45
3 to 4
Multi-stage pillars are harvested at the same time, and the top of the 1.0m roof is not collected.
Three nuggets in the stage of the Hongtoushan Copper Mine (13)
stable
stable
stable
Upward tailings filling method, the bottom 5 to 10 meters is layered sand cement filling
6
6 to 7.5
Hierarchical partitioning strip filling method
90.1
4.7
771 Mine (186-8 Nuggets in Leigongdian District)
Unstable
Upward horizontal dry filling
Concrete column filling method, each column support area 10m 2
80.4
4.9
6.8
Top column area 402m 2
721 Mine (3-8 Nuggets in Baiyun Mining Area)
stable
stable
not enough
stable
Ibid.
Concrete pillar on the top pillar
5~6
Upward horizontal partition dry filling, partition area 10 ~ 25m 2
91
9
The top layer is left with a 0.9m thick topping
741-1 uranium mine (6-3 nuggets)
Not too
stable
More stable
not enough
stable
Ibid.
Sub-section filling
78
17
3
The mining area is 200m 2 , and the 1.0m roof is not taken.
Yangjiazhangzi Molybdenum Mine No. 5 ore body more than 160m
Unstable
Upward horizontal layered filling method
9 to 10
Stratified caving
83～85
12.6
18～37
The grade is high, the surface is allowed to fall, and the production capacity is m 3 /d

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