Underground mining of rock gold deposits - comprehensive mining method

Comprehensive mining method is slow gold mining is an important method of mining the ore body tilt thin and very thin orebody. According to the 1987 data, the proportion of the total mining method applied to gold mines is 11.9% based on the mined ore. The gold mines applying this mining method mainly include: Shaoguan Gold Mine, Qinling Gold Mine, Xiangxi Gold Mine, Yu'erya Gold Mine, Zhangjiakou Gold Mine, Puqi Gold Mine, Banbishan Gold Mine, and Sanjia Gold Mine.

I. Technical conditions for mining

The deposits of all major gold mines using the comprehensive mining method are listed in Table 1.

Table 1 Technical conditions for mining mining using the comprehensive method

It can be seen from Table 1 that the ore body mined by the comprehensive method is mostly below 2m in terms of the thickness of the ore body, and a considerable part of it is a very thin ore body of less than 0.8m; from the inclination of the ore body, most of the ore body Below 30°, some of them are slightly inclined ore bodies below 5°; from the viewpoint of rock stability, most of them are moderately stable, but some are below moderately stable.

Second, mining method structural parameters

The main structural parameters of the comprehensive mining method for each gold mine are listed in Table 2.

Table 2 Structural parameters of the comprehensive mining method

It can be seen from Table 2 that when the gold mine applies the comprehensive mining method, the nuggets are arranged along the strike, and the size along the strike and the size along the slope are mostly 40-50 m. There are generally a column, a top column and a bottom column between the mine houses.

Third, the mining process

The mining process, parameters and equipment of the comprehensive method of each mine are listed in Table 3.

Table 3 Comprehensive mining method mining process

As can be seen from the 3, the comprehensive mining method of gold mines is diverse in the mining sequence and the mode of mining work in the mining blocks. Most of the mines use wall working faces to push from one side to the other. The mine divides the ore into several strips (Puchong, Banbishan Gold Mine) or divides into several sub-zones (Xiangxi Gold Mine) for mining. Individual mines (Zhangjiakou Gold Mine) adopt the way of roadway mining. These are mainly for Measures taken to accommodate different roof stability conditions. From the perspective of production technology, all of them are shallow-eye mines and electric mines (Puchun gold deposits are artificially mined). Among them, Shaoguan gold mine and Puqi gold mine use the comprehensive method to recover ore bodies with a thickness of 1.6m or less. At the time, the process of separation and distribution was adopted. The three gold mines and the Yu'erya gold mine still use mixed mining when recovering ore bodies with thickness less than the mining width. From the perspective of roof management, the Shaoguan Gold Mine and the Yu'erya Gold Mine have adopted relatively regular columns or cross-struts. All other mines use irregular ore pillars and wooden supports. Zhangjiakou Gold Mine is used because of poor roof conditions. Wooden sheds and wooden rafts. Some mines use anchors to reinforce the local roof.

Fourth, the main technical and economic indicators

The main technical and economic indicators for the comprehensive application of each mine are listed in Table 4.

Table 4 Main technical and economic indicators of the comprehensive mining method

It can be seen from Table 4 that the mining capacity of the comprehensive mining method is mostly 30 to 40 t/d, and the production capacity can be improved when stripping or separate mining is performed at the same time. From the ore loss and depletion indicators, the ore loss order is generally below 10%, and the ore depletion rate is high. Especially when the mine thickness is less than the mining width, if the mixed mining is still adopted, the depletion rate is high (such as three The gold mine has a thickness of 0.2 to 0.6 m and a depletion rate of 70%.

V. Review

When applying the comprehensive method, the gold mine is characterized by the convenience and flexibility of the mining method, which can be divided into mining and transportation. Generally, irregular ore columns are left in the stope, or low-grade ore sections and waste rock interlayers are left. To support the roof and reduce the ore depletion rate. The main direction of process development is to reduce ore loss and depletion. In the mining of thin and extremely thin ore deposits, there is a tendency to separate mining. For example, the comprehensive method of wall explosive force mining in the Shaoguan gold mine test and application will be located first. The rock in the middle and lower part of the mining frame is produced by throwing blasting, and then the ore in the upper part of the collecting frame is recovered, which greatly reduces the loss and depletion of the ore. Another example is the throwing blasting comprehensive mining method in the study of the Boaoshan Mine. The ore is divided into several mining strips. In the center of each strip, the rock is first mined and formed into trenches, and then the ore on both sides is thrown and blasted. The method is carried out in the trench and transported out, which reduces ore loss and depletion, and improves the production capacity of the ore block. The Zhangjiakou gold mine applied the approach of mining and mining, and applied the comprehensive mining method to the condition that the roof is unstable, and achieved good results. According to the different way of the way of the way, parallel approach, mine approach and fishbone were adopted. A variety of options such as access.

The main features of the application of the comprehensive mining method in gold mines are: low level of mechanization and small production capacity of the ore; heavy physical labor and low labor productivity; high ore loss rate when the mine room column and the top and bottom columns cannot be effectively recovered. .