Cement filling and mining method components and mining, cutting and mining processes

(1) No filtering well

Generally no drainage wells, individual mines (such as focal points gold mine) set the filter back to the well. High grade cement and flocculant are used in the cemented filler. If you let it filter out a lot of water, it will not help the hardening of cement. (But it can't make the water too much. The excess water will make the filling body form a honeycomb, which will reduce the strength of the filling body.) (The focal point gold mine has a filtering well, solid linen, and the eyes are blocked. this problem.)

The cementation filling method is mainly dewatering by overflow.

(2) Formation of the slippery well

The chute does not have to be specially built, as long as the template is laid in advance, but when filling with low-grade materials, it is necessary to build a chute.

(3) When the ore nuggets are harvested, the transportation level is fully opened at the stage, and artificial roadways and artificial rot columns are built with concrete. The mining of the nuggets is always carried out to the upper stage of the concrete pillar. Do not leave the top column.

(4) Topping method—In many cases, it is required to protect the surface and not allow large movements of the rock formation and surface subsidence. Therefore, the topping problem has become one of the key issues.

There are several ways to connect the top:

1) Manual topping method—that is, the last filling layer is divided into several 1.5-meter-wide strips, then one strip and one strip. Before pouring, set the template (1.0 m high) first, then gradually increase the template as the casting body is raised. FILLING MATERIAL rely on iron shovel was sent to the template. When filling only about 0.5 meters from the top plate, use stone or concrete brick to build the roof, so that the residual space is completely filled. This method of connection is reliable. But the labor is heavy, the efficiency is low, and the amount of wood consumed is large.

2) Mortar pressure connection method—that is, a method of pressing the mortar along the pipeline into the ceiling space with a hydraulic pump to fill the ceiling space. Strictly do the sealing work of the ceiling space before the topping. (Clog the roof and cracks on the state, etc.). This method is better as long as the pressure is sufficient. (This method is used in Jiaoxue Gold Mine).

3) [Reference content] 1 Wind filling and filling method using concrete pump and concrete pouring machine. China's keel mine has been tested. The results show that the effect is good, and the gap left by the solid side top plate is small, only a few centimeters, and these centimeters are still the result of hardening shrinkage of the concrete body.

2 Jet type topping method - Japan uses this method to connect the top. It is to lay the filling pipe on the top plate of the top filling space, and appropriately increase the residual pressure of the mortar flow in the pipe so that the discharged mortar has a certain The pressure and speed are such that an upward flow of mortar is created, causing the filling to fill the ceiling space.

(3) Materials used for cement filling

Cementing filling materials include: cementitious materials, coarse aggregates (the coarse aggregate size is generally 5 to 50 mm. The maximum is not more than 1/3 of the diameter of the conveying pipe), fine aggregate and water.

1 cementing material - China uses cement. 2 coarse aggregate - gravel, pebbles. 3 fine aggregate - river sand, tail sand. (Some mines in the northwestern region use the aggregate) (fine aggregate refers to sand with a particle size of 0.15 to 5 mm. The tailings and fine aggregates after classification have a particle size of 0.03 mm)

The amount of cement used is large, and people seek substitutes. (E.g. furnace ballast, magnetic iron sulfide powder coal ash, lime, aluminum plant process red mud, are made into cementitious material) (at the cost of filling, the cement proportion is generally cost more than 40%. Since silicic acid The price of salt cement is very high, and the amount of cement in the filling of 1 ^{m3 is} 150-350 kg.)