Room and pillar mining method - Epiroc

Summary

Room and pillar mining is a flexible and productive method used to mine ore bodies with dips of less than 50 degrees. The technique involves creating a grid system of open rooms supported by pillars to stabilize the overhead rock mass. The size of the rooms and pillars is optimized based on rock conditions to recover maximum ore while ensuring safety. The process involves sequential activities like drilling, blasting, and creating roadways for transport. Room and pillar mining adapts well to changing market conditions, but some ore loss is inevitable. Rock reinforcement and careful blasting practices help maintain pillar strength, minimizing risk and maximizing ore recovery.

Takeaways

• 😀 Room and pillar is a common mining method used for ore bodies with a dip of less than 50 degrees.
• 😀 Variations of the room and pillar method exist, depending on rock conditions, ore body dip, and thickness.
• 😀 A grid system of open rooms combined with pillars is used to support the overhead rock mass during mining.
• 😀 The mining sequence can be optimized for rock conditions and ventilation requirements.
• 😀 Ore is typically mined using a drill and blast technique, with drifts becoming the rooms between pillars.
• 😀 Key to success in room and pillar mining is optimizing room and pillar sizes to maximize ore recovery and minimize pillar size.
• 😀 Room and pillar mining design is based on rock conditions and predicted rock stress changes to ensure safety.
• 😀 In areas with larger roof spans, additional reinforcement such as cable bolts may be necessary alongside rock bolts.
• 😀 Accurate drilling and good blasting practices are crucial for minimizing overbreak and maintaining pillar strength.
• 😀 Various transport methods can be used for moving ore to the surface within a well-planned room and pillar mine.
• 😀 Room and pillar mining is flexible and can respond quickly to changes in market conditions, though it can result in some ore loss.

Q & A

What is the room and pillar mining method?

Room and pillar is a common mining method used for mining ore bodies with a dip of less than 50 degrees. It involves creating a grid system of open rooms and pillars to support the overhead rock mass.

How does the mining sequence in room and pillar mining work?

The mining sequence is optimized to accommodate rock conditions and ventilation demands. The ore is mined using a drill and blast technique, where the drift becomes the room between the pillars.

What factors influence the size of the rooms and pillars in room and pillar mining?

The sizes of rooms and pillars are based on rock conditions, predicted rock stress changes, and safety considerations. The goal is to recover the maximum amount of ore while leaving the smallest possible pillars behind.

Why is it important to optimize the sizes of rooms and pillars?

Optimizing the sizes ensures the maximum recovery of ore while minimizing the size of the pillars left behind, which helps in reducing ore loss and maximizing efficiency without compromising safety.

What safety measures are taken when working in areas with larger roof spans?

In areas with larger roof spans, rock reinforcement such as cable bolts may be required in addition to regular rock bolts to ensure safety.

How does accurate drilling and good blasting practice affect the mining process?

Accurate drilling and good blasting practice help minimize overbreak and blast damage to the pillars, maintaining their strength and preventing pillar failure as the ore is mined.

What is the role of roadways in room and pillar mining?

Roadways are created inside the production area for transportation and infrastructure. They are essential for moving equipment and ore within the mine.

How can room and pillar mining respond to changing market conditions?

Room and pillar mining is flexible, allowing it to quickly adjust to changing commodity prices and market conditions, which makes it adaptable to economic shifts.

What is one of the disadvantages of the room and pillar mining method?

One of the disadvantages of room and pillar mining is the inherent ore loss, as some ore is left behind in the pillars to support the overhead rock mass.

How does room and pillar mining contribute to productivity and efficiency?

Room and pillar mining is productive and efficient, as it enables the use of multiple production points and various transportation methods, maximizing the use of equipment and allowing for efficient ore transport to the surface.