Cave Mining Pre-conditioning via Fracturing

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional underground mining methods face inefficiencies due to discreet and intermittent material handling processes, which hinder continuous ore extraction and result in suboptimal productivity and resource utilization.

Innovation Solution

The implementation of a continuous mining method involving rock pre-conditioning through hydraulic fracturing and Explosive Driven Dynamic Weakening, combined with a system of simultaneous extraction from multiple draw points using stationary equipment and metal belt conveyors for continuous haulage, allowing for a continuous and automated ore flow.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If conventional discreet and intermittent material handling is used, then equipment simplicity is maintained, but productivity and resource utilization deteriorate

Engineering Contradiction:
Improveextraction rateVSAvoidmaterial handling system complexity
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

The patent implements continuous material handling by replacing intermittent wheel loader cycles with a continuous conveyor belt system that operates without interruption. The conveyor belt receives ore from multiple draw points simultaneously and transports it continuously to the shaft, eliminating the start-stop nature of conventional loading equipment and achieving uninterrupted ore flow throughout the mining operation.

Inventive Principle:
Principle #20Continuity of useful action

Solution Approach 2:

The patent combines multiple draw points into a single integrated material handling system. Instead of having separate loading operations at each draw point, the conveyor belt system consolidates ore from multiple simultaneous draw points into one continuous transport stream, merging multiple discrete operations into a unified continuous process that improves overall productivity.

Inventive Principle:
Principle #5Merging (Combining)

2Manufacturing precision

If pre-conditioning fracturing is applied, then rock fragmentation quality improves, but process complexity and energy consumption increase

Engineering Contradiction:
Improverock fragmentation qualityVSAvoidenergy consumption
Core Design Contradiction:
Manufacturing precisionVSUse of energy by moving object

Solution Approach 1:

The patent applies pre-conditioning fracturing before the main caving and extraction process. By introducing hydraulic fractures and Explosive Driven Dynamic Weakening in advance, the rock mass is prepared with predetermined fracture patterns that guide subsequent natural caving. This preliminary action ensures that when caving occurs, the rock breaks into optimally sized fragments for continuous handling, improving fragmentation quality while allowing the main extraction to rely on natural gravitational forces rather than requiring continuous high-energy fracturing.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent uses hydraulic fracturing as an intermediary process between the natural rock mass and the final caving extraction. The hydraulic fractures create initial pathways and stress concentrations that mediate the transition from intact rock to caved material. This intermediary action prepares the rock structure to respond more efficiently to subsequent gravitational caving, reducing the total energy required for complete fragmentation while ensuring consistent fragment size distribution.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Productivity

If continuous extraction from multiple draw points is implemented, then productivity increases, but system complexity and coordination requirements worsen

Engineering Contradiction:
Improveextraction rateVSAvoidextraction system complexity
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

The patent employs a universal conveyor belt system that serves multiple draw points simultaneously. The same conveyor infrastructure handles ore from all draw points, providing a multi-functional transport solution that simplifies coordination compared to having separate loading systems for each draw point. This universal system maintains continuous operation while managing the complexity of multi-point extraction through a single integrated transport mechanism.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This approach enhances extraction rates, improves resource utilization, and maintains continuous operation with increased productivity and safety, achieving higher extraction rates and better resource management compared to traditional methods.

Implementation Method 1

rock pre-conditioning through hydraulic fracturing

Methodology Applied
Scientific EffectHydraulic fracturing: Fracture Mechanics

Implementation Method 2

Explosive Driven Dynamic Weakening

Methodology Applied
Scientific EffectExplosive Driven Dynamic Weakening: Explosion

Implementation Method 3

ground breaking itself is a continuous process of fracturing and fragmentation that makes use of natural forces of gravity

Methodology Applied
Scientific EffectGravity: Gravitation

Data Source

PatentEP2370673B1Pre-conditioning for cave mining by fracturing
Publication Date: 2019.02.27 CORPORACION NACIONAL DEL COBRE DE CHILE
  • EP2370673B1 patent drawingFigure 1
  • EP2370673B1 patent drawingFigure 2
  • EP2370673B1 patent drawingFigure 3~4

AI summary

A method useful in the continuous ore extraction in underground works intended for the permanent production of extraction from draw points or trenches, comprising the construction of reduced size drifts (4) wherein through the center defined by a group of drifts crosses a drift (2) which is intended for ore haulage, such drift crosses successively all drift groups defined at the exploitation face,- such extraction points (11) are arranged to form a regular layout [m4] at certain distances which are compatible with an interactive gravitational flow; once such drifts, trenches and haulage drifts are constructed the pre-conditioning, caving and extraction stages are carried out.