advantages-of-the-filling-method-in-deep-gold-mining

Deep gold mining, as a critical area in mineral resource development, faces multiple challenges including complex geological conditions, high technical demands, and significant safety risks. As mining depths extend to 800–3000 meters underground, extreme environmental factors such as high pressure, high temperature, faults, and fractured geological structures significantly increase the difficulty of ore body prediction and extraction. Simultaneously, deep mining relies heavily on technology, necessitating modern information systems for process management and safety control. The high costs associated with equipment investment and ventilation system construction further highlight the critical importance of selecting appropriate mining methods.

Among various mining techniques, the Pre-controlled Roof Segmented Post-filling Method has demonstrated significant practical advantages through field verification. This method represents an optimized upgrade of the upward-level layered and drift cemented combined filling mining technique. Through innovative working layout and process design, it effectively balances mining efficiency, safety assurance, and cost control. Its core advantage lies in the scientific design of the mining area structure. The mine room is arranged vertically along the ore body strike, divided into three 20-meter-wide panels. Using a bottom-up filling method for extraction, combined with manually constructed filling retaining walls, it achieves effective isolation between local reinforcement and filling slurry, significantly enhancing mining area stability.

Regarding access development and mining techniques, the pre-controlled roof sectional backfilling method employs medium-deep hole mining. Compared to traditional mining technologies, this approach reduces pillar access development and cutting work by nearly 50%, significantly boosting mining efficiency. This method comprises two stages: room-and-pillar mining and pillar mining, both following a bottom-up sequence. Rooms are filled using an upward horizontal layered filling technique, while pillars are mined through upward medium-deep hole blasting. Parameters—65mm borehole diameter, 1.8m depth, and 1.5m–1.7m spacing—ensure optimal blasting effectiveness and operational safety. Additionally, roof reinforcement employs 3×3m spaced long-anchor cables + shotcrete mesh, further enhancing structural stability and effectively mitigating dynamic hazards like rock bursts and goaf subsidence.

This dual assurance of economic and safety benefits makes the method the preferred solution for deep gold mining. Industrial trial data shows that applying the pre-controlled roof sectional post-filling method achieves a daily production capacity of 588 tons, with dilution and loss rates both controlled at low levels of 9%–10%. The cut-to-fill ratio is only 12.5m/kt, significantly lower than other comparable technologies. For the deep ore body with reserves of 6.28 million tons, this method can increase the recovery rate by approximately 5%, adding about 926.46 kg of additional resource recovery, with a total value reaching 467 million yuan. Simultaneously, its comprehensive safety management system, combined with rock dynamics analysis and 3D laser monitoring technology, effectively addresses risks such as high temperature, high pressure, and gas hazards, providing all-around protection for mining operations.