Process Analysis of Open-Pit Mining

Open-pit mining, as a primary method for mineral resource extraction, is widely used in metal ore exploitation due to its efficiency and cost-effectiveness. However, it involves complex geological environments, heavy machinery, and blasting operations, posing significant safety and environmental challenges. This paper systematically analyzes the core processes, existing issues, and optimization strategies of modern open-pit mining, integrating technological advancements and safety management practices.

1. Core Process Technologies in Open-Pit Mining

1. Perforation Technology

Perforation is the initial step, directly impacting subsequent blasting and mining efficiency. Mechanical perforation (e.g., rotary drills) and thermal perforation (e.g., flame drills) are commonly used. Advanced equipment like rock drilling jumbos enhances precision, particularly in hard rock layers, reducing energy waste and secondary fragmentation needs.

2. Steep Slope Mining Technology

For deep concave mines, steep slope mining optimizes stability by controlling stripping volume. Techniques include bench or inclined strip mining, requiring structural analysis of ore bodies and strict bench design to prevent instability.

3. High-Bench Mining Technology

Larger equipment enables higher benches (15–20 meters), increasing single-pass extraction. Depth control and high-power excavators (e.g., electric shovels) are critical. Adjustments based on geological conditions ensure slope safety.

4. Blasting Technology

Blasting determines rock fragmentation and cost efficiency. Modern practices employ "large-area micro-delay blasting" with non-electric detonation systems to minimize vibrations. Secondary fragmentation (e.g., rock drills and explosives) reduces oversized fragments, enhancing transport efficiency.

5. Waste Dumping Technology

Efficient dumping ensures slope stability and ecological protection. Truck-dozer combined dumping is prevalent for flexibility. Dump sites require slope design and compaction to prevent landslides, with drainage ditches to mitigate rainwater erosion.

6. Backfill Mining Technology

Backfilling with materials like paste or gravel stabilizes goafs, reducing subsidence. Tailored material ratios and transport solutions are vital for complex terrains.

2. Challenges in Open-Pit Mining Processes

1.    Safety Risks
Outdated technologies and poor management lead to accidents (e.g., slope collapses). Over 30,000 fatalities occurred in China’s metal mines in the past decade, necessitating technological upgrades.

2.    Environmental Pollution
Noise from blasting and machinery affects communities, while improper wastewater and waste disposal contaminates soil and groundwater.

3.    Slope Instability
Soft rock geology, rainfall erosion, and improper technology selection trigger collapses, threatening safety and progress.

4.    Drainage System Flaws
Inadequate drainage causes waterlogging in rainy seasons, disrupting transport and increasing landslide risks.

3. Optimization Strategies for Safety and Efficiency

1.    Technological Upgrading
Adopt intelligent equipment (e.g., autonomous trucks, AI monitoring) and green technologies (e.g., low-noise drills) to enhance precision and reduce pollution.

2.    Standardized Management
Establish a safety management system with real-time monitoring (e.g., slope displacement via IoT) and standardized protocols for risk prevention.

3.    Slope and Drainage Management
Use ground-penetrating radar for slope monitoring, combined with reinforcement and vegetation. Improve drainage with sedimentation ponds and rainwater diversion.

4.    Training and Safety Culture
Regular safety drills and training foster a proactive safety culture. Implement a "total safety responsibility" system linking performance to accountability.

4. Conclusion

Optimizing open-pit mining requires innovation-driven strategies, integrating automation and sustainability. With AI and big data applications, the industry will advance toward safer and greener practices. Continuous improvement in technology and management is essential for enterprises to achieve efficient and sustainable mining in complex environments.