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Summary

This video explains a vertical shaft mining method used to extract mineral deposits. The process involves breaking the mineral, using it as a working floor for further extraction, and creating pillars for support. It details the steps, including ventilation, access points, and transportation of extracted material. It also highlights the necessary conditions for applying this method, such as the mineral's characteristics and the stability of surrounding rocks. The video discusses both the advantages and challenges of this mining technique, including production rates, labor intensity, and safety considerations.

Takeaways

• 😀 The vertical vein exploitation method involves using broken mineral as a floor for working, allowing for upward mineral extraction.
• 😀 Pillars are used as support structures, exploited after the production process ends, and are part of the structural setup.
• 😀 The mining method requires ventilation and access shafts (chimneys) to ensure the continuity of the vein and provide access for personnel and equipment.
• 😀 The extracted mineral is transported using pneumatic systems and low-profile trucks to the hopper for further processing.
• 😀 The method is best suited for narrow veins with mineral exposure between 1 to 30 meters in width and requires competent surrounding rock for safety.
• 😀 Levels in the mine are separated by distances of 30 to 180 meters, with multiple chimneys for access and ventilation.
• 😀 Manual labor is needed due to difficult terrain, using tools like the 'yate' or 'stoppers' for drilling, instead of mechanized equipment.
• 😀 Ventilation is maintained by injecting air from the transportation gallery to ensure airflow at the work face.
• 😀 Fortification methods include bolting or mesh installation depending on rock stability, with more unstable areas requiring more extensive support.
• 😀 The method is not suitable for clay-rich or cemented materials, as they can cause dangerous conditions, including collapsing rocks.
• 😀 The method offers a good recovery rate of 75% to 100%, but is labor-intensive and comes with moderate to high costs due to manual operations.

Q & A

What is the method of exploitation described in the script?

The method described is a vertical shaft exploitation technique that involves using broken mineral as a working floor to continue mining upwards.

What are the key components of this exploitation method?

The key components include a pillar for support, walls known as 'rocas en cajón', ventilation and access chimneys, service levels, extraction levels, and the use of pneumatic drills to transport the mineral.

What are the conditions for applying this method of exploitation?

This method is suitable for narrow veins with widths between 1 to 30 meters. The mineral should not be easily collapsible or oxidized, and the angle of repose should be greater than 55%. The surrounding rock should be competent.

What role do the chimneys play in this exploitation method?

Chimneys are used to define the continuity of the mineral vein, as well as to provide ventilation and access for personnel and equipment.

What are the difficulties associated with accessing the terrain in this method?

The terrain's irregularity makes it difficult to use mechanized drilling equipment, so manual drilling methods such as 'yate' or 'stoppers' are used instead.

What types of drilling and blasting techniques are used in this method?

Blasting is done using gels and emulsions with non-electric initiation. Drilling is done using horizontal or vertical boreholes, with diameters ranging from 32 to 38 mm.

How is ventilation managed in the workfront?

Ventilation is managed by injecting air from the transport gallery through the access chimneys to ensure proper airflow in the working area.

What methods are used for fortifying the work area?

Fortification methods include the use of partial or systematic bolting and mesh installation. In more unstable areas, additional support measures are used.

What are the potential risks of using this method in clayey or cemented materials?

In clayey or cemented materials, the method is risky as the hanging walls can collapse. Manual handling of such material can be dangerous and expensive.

What are the advantages and disadvantages of this method?

Advantages include relatively low capital costs, moderate mechanization, and good recovery rates of 75-100%. Disadvantages include moderate to high costs, intensive labor requirements, and the fact that up to 60% of the mineral may remain trapped in the pillars.