EM 10 - 11 Mining Method Selection (Part 2)

Summary

In this lesson on mining method selection, the instructor covers key factors influencing the choice of mining techniques. Economic considerations, such as profit potential and production rates, are vital. Technological factors, including ore recovery and selectivity, are also important, along with environmental and safety concerns. The process of mining method selection involves conceptual, engineering, and detailed design studies. Surface mining, while safer and cheaper, disturbs more land, while underground mining is riskier but less disruptive. The ultimate goal is to balance profit, safety, and environmental impact. The lesson concludes with a comparison of surface and underground mining methods.

Takeaways

• 🤑 Economic considerations are crucial in mining method selection, as profitability drives decision-making.
• 🏗️ Production rate and cash flow are important economic factors in determining mining profitability.
• ⛏️ Reserves, resources, and mine life help gauge the duration a mine can remain profitable.
• 📊 Recovery rates, dilution, and ore body characteristics must be evaluated to select the most efficient mining method.
• 🔍 Selectivity is key in choosing a mining method that optimally extracts ore while minimizing waste.
• 🌍 Environmental concerns, like ground control and waste disposal, play a role in mining decisions, especially in surface mining.
• 🤖 Technological factors, such as mechanization and automation, impact the selection of mining methods.
• 🚨 Safety considerations, including personal protective equipment (PPE) and proper ventilation, are vital in underground mining.
• 📝 The engineering evaluation process (conceptual, engineering, and detailed design studies) guides mining method selection.
• 💼 Surface mining is cheaper and safer but disturbs more land, while underground mining is costlier but affects less surface area.

Q & A

What are the six factors involved in mining method selection?

The six factors involved in mining method selection are ore body characteristics, safety, economic considerations, technological factors, environmental concerns, and the social, political, and economic climate.

Why are economic considerations crucial in mining method selection?

Economic considerations are crucial because mining is a business. The goal is to make a profit, so the chosen method must be economically viable. Even if there are reserves left, if the extraction would lead to a loss, it is best to leave the ore where it is.

What is meant by 'planned' and 'unplanned' dilution in mining?

Planned dilution refers to the waste rock that is expected to be extracted along with the ore as part of the mine design. Unplanned dilution occurs when errors in the mining process lead to the unintentional extraction of additional waste rock.

How does the ability to mechanize affect mining method selection?

The ability to mechanize refers to the potential for using machinery in the mining process. This can influence the choice of method as mechanized methods can increase efficiency and reduce labor intensity but may have higher capital costs.

What is subsidence in mining, and why is it a concern?

Subsidence is the vertical movement of the ground above an underground mine. It is a concern because it can affect the surface environment, cause structural damage, and create safety hazards for nearby areas.

What role does worker safety play in mining method selection?

Worker safety is a top priority when selecting a mining method. Factors such as the mine's layout, ventilation, and working conditions underground must be considered to ensure the safety and well-being of the workforce.

What are the steps involved in the engineering evaluation process for mining method selection?

The engineering evaluation process consists of three steps: the conceptual study, the engineering study, and the detailed design study. These steps involve comparing possible methods, creating an initial design with cost predictions, and finalizing the detailed design.

How do surface mining and underground mining differ in terms of environmental impact?

Surface mining generally disturbs a larger area of land and produces more waste, while underground mining disturbs less land but poses greater safety risks due to the confined spaces and potential for collapse.

What are the advantages of surface mining over underground mining?

The advantages of surface mining are that it is safer and relatively cheaper compared to underground mining. However, it also disturbs a larger area and generates more waste.

What is the importance of the final engineering report in mining?

The final engineering report is crucial as it contains all the detailed plans for the mine, including investment decisions, equipment purchases, and the construction schedule. It also includes plans for the closure or rehabilitation of the mine after operations end.