What is the difference between backfill mining and caving mining?

Backfill mining and caving mining are two different underground mining technologies, each with its own unique characteristics and applicable conditions.

1. Backfill mining

Definition: Backfill mining is a mining method that uses backfill materials to fill the goaf during the mining process to support the surrounding rocks on both sides, prevent rock movement, and achieve the purpose of controlling ground pressure.

Applicable conditions: Applicable to deposits where the ore is stable but the surrounding rocks are not stable enough, where the surface is not allowed to collapse, where rare and precious metals or high-grade rich ores are mined, and where there is a risk of spontaneous combustion of the deposit.

Advantages: High ore recovery rate, low depletion rate, can effectively maintain the surrounding rock, reduce the movement of the surrounding rock and prevent a large amount of caving, and has a good control effect on surface subsidence and deformation.

Disadvantages: The mining process and backfilling process are complex, and backfilling and mining affect each other, which may lead to low production efficiency and production capacity, and high costs for mining, processing, and transportation of backfill materials.

2. Caving Mining

Definition: Caving mining is a method of planned caving of surrounding rock to fill the goaf during the mining process, regardless of the ore room and pillars, as the mining face advances.

Applicable conditions: Applicable to ore bodies with unstable surrounding rock, precious ore, and surface protection, as well as ore bodies with an inclination of generally above 50° to 60°.

Advantages: The mining site structure is simple, which is conducive to the mechanization of mining operations, can reduce the workload of mining and improve mining efficiency.

Disadvantages: It may lead to large ore losses and depletion, and the problems of surface subsidence and ground pressure management are more complicated.

In general, the filling mining method focuses more on the maintenance of surrounding rock and the control of surface subsidence, while the caving mining method focuses more on the optimization of mining efficiency and cost. When choosing a mining method, mining companies need to decide which mining method to adopt based on specific geological conditions, technical requirements and economic considerations.