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By Aris Tambunan, Nella Lubis, Nurafrianti Saala, Komang Widhiayanto, Herry Saputra, Rudolf Sitorus

Maximizing mining recovery rates and minimizing ore loss are pivotal objectives for economic efficiency and operational effectiveness. This study explores methods to address these imperatives by enhancing ore production and recovery through improved blasting techniques and spillage control in the Martabe Gold Mine Project in North Sumatra Province, Indonesia. Between 2018 and 2021, the average mining recovery rate stood at 93%, resulting in a potential annual ore loss of 7% and a potential quarterly financial impact of close to $2 million. Maintaining and enhancing mining recovery became crucial, with a planned 30% increase in total material movement for 2022. The mining recovery target for 2022 was set at 96% based on best achievement historical data from 2021 to increase ore tonnage by 203 KTon per annum. To achieve the primary objective of increasing ore production by improving mining recovery, the study focused on predicting and controlling the movement of blasted ore to reduce spillage and enhancing the grade control model to reflect actual conditions post-blasting. Several alternative solutions were explored, primarily emphasizing drilling and blasting activities. Essential methods included capturing the actual blasting movement to adjust the ore block based on blasting design data and post-blasting muckpile topography. This approach minimizes ore loss by providing output as ore block adjustment based on post-blast movement data. In addition, the tie-up design was adjusted to control ore spillage outside the pit ridge. The implementation of these methods yielded significant improvements. Adjusting the ore block based on actual blasting movement contributed $1,545,764 in benefits. Controlling ore spillage outside the pit ridge achieved a 10% reduction in spillage, contributing $79,184 in benefits. These enhancements successfully met the 2022 mining recovery target of 96%, marking a 3% increase from 2021. Consequently, ore loss was reduced by 178 KTon throughout 2022, resulting in a financial impact of $7.3 million. The study underscores the significance of precise blasting techniques and effective spillage control in enhancing mining recovery rates.

Jan 21, 2025

By Robert Lee, Pertti Paavola

Automated vibration monitoring and web-based data distribution has proven itself on the largest single construction project ever undertaken in Finland. The excavation for the Kamppi Center Project in the center of Helsinki was completed in November of 2003 and involved the removal of over 200,000 m3 (260,000 yd3) of rock and over 1,700 individual blasts. A system was installed, incorporating 37 discrete monitoring points located throughout an underlying metro station, and other surrounding underground and surface facilities. After every blast, vibration data was automatically transferred from the monitoring network to a server database. Stakeholders were able to access and review vibration reports on a password-protected website within 90 seconds of each blast. This allowed engineers to verify that recorded levels were in compliance with established limits, before proceeding with subsequent blasts. The data was also imported into a semi-automated Scaled Distance tool for analysis using linear regression techniques. This was used to determine, and adjust for trends in blast-induced vibration.Copyright

Jan 1, 2004

By R L. Mayville

The author explains why the strategic location and important limestone reserves at Chattanooga Quarry led to a decision to extend operating life by continued benching down to lower levels. He discusses the steps taken to accomplish this objective. These include relocation of the primary crusher from the second level to the fourth level, pre-testing of explosives designs and powder factors, control of a substantial water problem, and computer monitoring of stone production costs.

Jan 1, 1984

By Braden Lusk

A typical rural house surrounded by a surface coal mine was instrumented in 2008. Information regarding ground vibration, airblast, and sounds inside the house was collected. Previous publications have included conclusions about this data with regard to blasting source (far-field or near-field) and results as to how the residents experience the blast were made. Several events were also recorded that were not related to blasting due to the nature of the trigger system. The trigger of the monitoring system was attached to one of the mid walls of the house, thus other normal daily events produced vibration levels significant enough to trigger the monitoring system.

Jan 1, 2011

By John Hutchings

Drilling and blasting is a clearly delineated work process, which has well defined inputs and outputs. Drilling and blasting is also a process with a number of steps each of which has measurable outcomes. Drilling and blasting is ideally suited to the application of Total Quality Management principles. Most drilling and blasting information is generally poorly managed with disjointed and unrelated Information Technology systems managing parts drilling and blasting data. Data is often moved from on system to another, sometimes manually. In the field, drilling and blasting is still very much a paper based system and which has not generally benefited from some of the recent hardware and software technology advancements now “on the shelf”. Data collected on paper rarely is transcribed back into an electronic system for further analysis. It is often difficult to collate or review historic drilling and blasting data. This paper will present a definition of Total Quality Management and demonstrate how it can be applied to the drilling and blasting work process. Total Quality Management defines the mechanisms for the application of continuous improvement to drilling and blasting. Continuous improvement will provide opportunities to modify drilling and blasting work process outcomes and generate real cost benefits within the overall mining process. A complete drilling and blasting management system frame work, called DBS, is presented in this paper. DBS provides all the components necessary to implement a full drilling and blasting Total Quality Management solution. Also highlighted will be appropriate “off the shelf” technology that can be applied to replace current paper based systems and provide the means to connect with other mine data systems. Various examples will be discussed which will demonstrate potential benefits of applying a structured Total Quality Management approach to a drilling and blasting work process.

Jan 1, 2004

By Ruilin Yang

This paper provides a theoretical analysis of shockwaves in an air-deck induced by detonation of an explosive charge and shows that the initial shock pressure in the air-deck at the interface with the explosive charge is only about 1% of the detonation pressure. A rarefaction wave with the low pressure travels back into the explosion detonation products greatly reducing the post-CJ detonation pressure. Additionally, AUTODYN modelling shows that the pressure attenuates further during shockwave propagation along the air-deck. Although the pressure increases at the bottom of the blasthole due to shock reflection, the overall pressure in an air-deck does not increase and is still around 1% of the detonation pressure which is too low to break most rock.

Jan 1, 2016

By Jon Hurt, Brent Meins, David Vardiman

"Two test blasts were conducted at the Sanford Underground Research Facility to establish optimum blast designs and to limit blast effects on existing research rooms and equipment in preparation for the largest deep underground excavation in North America. Located on the 4850 Level (4,850 ft below the surface)at the former Homestake Mine in Lead, SD, this excavation is part of the U.S. Department of Energy’sLong-Baseline Neutrino Facility that will house particle detectors for the international Deep Underground Neutrino Experiment hosted by Fermilab. A large array of seismographs was deployedthroughout the 4850 Level to measure ground vibrations and airblast pressures in tunnel drifts and in lab spaces."

Jan 1, 2017

By Gordon C. Petersen, Gary A. Almeraris

This paper describes the controlled blasting techniques required to mine a rock tunnel section of a main interceptor located in the Boston Metropolitan area. The 3m (10 ft) x 2.8m (9.25 ft) horseshoe shaped tunnel was driven 490m (1600 ft) by conventional drill and blast methods. The geology varied round by round and consisted of five highly faulted and jointed igneous rock types. The tunnel intersected numerous slickenslides and open mud seams which hampered both drilling and loading operations. Smooth blasting wee critical in order to keep overbreak tc a minimum in this extremely hard but blocky ground.

Jan 1, 1991

By Les Willan, Chris Batten, Matt Sparkes

In late 2008 Xstrata Newlands Coal Mine in Central Queensland and Orica Mining Services engaged in discussion to investigate methodologies to change their current mining practices and overcome the issues in the mining of steeply dipping coal seams, the associated coal loss risk and to assist in improving mining productivity. A strategy was developed and it was determined that through-seam blasting was essential to the success of winning the coal from the Wollombi Pit at Newlands.

Jan 1, 2010

By Alain Blanchier, Anne Charline Sauvage

Rock mass variations have a huge influence on explosives efficiency and on blasting results. Numerous blasting improvements could be gained by taking into account rock mass and its variations. However, extracted rock mass is generally considered as statistically homogenous. The development of a panel of pre-blast survey procedures that every blaster can use, consists in the realization of a process integrated into every day work: for example as well as toe burden or blast hole depth, discontinuities spacing or the weathering expanse have to enter in rule book, if it provides blasting efficiency and security improvements.

Jan 1, 2004

By Karl Peterson, Bibhu Mohanty, Chanakya Nariseti

The mechanism of crack formation in two target rocks (Kuru granite and Flamboro Limestone) is studied experimentally by simulating the impact action of a percussive drilling bit. Rock samples are dynamically loaded using a custom made impacting bit (8 mm, 12 mm and 15 mm diameter bits). The target rocks are impacted at velocities 8, 10, and 12 m/s. The resulting crack patterns are visualized by three techniques, Dye penetration, CAT scans and Optical scans. Mapping of the crack patterns is manually done with Photoshop. For 3D damage visualization, the crack patterns are mapped in two planes (impact surface and longitudinal sections). The three techniques are compared to determine an optimum technique for better damage visualization. The evolution of crack pattern with impact velocity and bit diameter is discussed.

Jan 1, 2015

By Travis A. Davidsavor, Charles Dowding, David A. Provost, Yonggang Gou

This paper compares measured blast induced strains on operating, full scale, buried pipelines with three similar past studies. The recently performed study represents realistic and modern pipeline blasting techniques combined with modern data acquisition. The evaluation compares measured PPV and strain, as well as calculated stress, at equivalent scaled distances.

Feb 1, 2020

By David Porter, Nathan Rouse

The implementation of presplit perimeter control in underground mining as a method to decrease dilution yields positive benefits throughout the current and future mining cycles. A case study to understand the benefits of reducing overbreak and underbreak in a cut and fill mining cycle was performed to quantify the reduction in backbreak. The study was performed in a control section of the mine where a presplit perimeter control design was utilized for a length of heading. This control heading was then compared to the existing standard blasting design within the same mining zone. The comparison included multiple aspects of the mining advance including overbreak, dilution of waste, dilution of Cemented Rock Fill, bolt counts, and cycle times. Once mining in the control section was completed and mining commenced in adjacent headings, blast damage due to blast design could be quantified.

Feb 6, 2023

By D E. Shaw, J B. Case, J Gusek

Explosive casting of overburden is defined as the use of explosives in blasting to move overburden to a spoil pile without rehandling. Studies of the economic feasibility of the method, and the formulation of a design hypothesis involving rock properties, and blasthole geometry are presented. These studies indicate that if technical feasibility can be demonstrated to increase surface coal production, considerable economic advantage would accrue to coal mine operators.

Jan 1, 1980

By Andrew Wetherelt

Blast vibrations are of paramount importance in a society where ever increasing development is putting more stringent requirements on their control. Increasing civil development and more complex extraction scenarios make the trade off between proficient vibration control and productivity difficult to ascertain. Historically, reduction of induced vibrations levels was achieved through a reduction of MIC’s leading to smaller but more frequent blasts in order to meet extraction targets.

Jan 1, 2007

By Nickolas Vlahopoulos, Nicholas Stowe

A concept has been proposed for the focusing of underwater energy. An array of spherical TNT charges is used to achieve this aim. The goal of the present research effort is to model such a system and identify optional arrangement and detonation timing schemes. A fast-running model is necessary to perform optimization analysis due to the highly iterative nature of most optimization algorithms. This requirement renders the use of sophisticated numerical solvers impractical. An analytical, physics-based model must be developed to satisfy the demands of the multiple charge optimization problem. This model must capture shock propagation speed, pressure-time histories throughout the fluid domain, and multiple charge interaction phenomena. Such a model is presented herein.

Jan 1, 2012

By Richard Turnbull

Maules Creek mine is an open cut coal near Boggabri in the Gunnedah Basin of New South Wales, Australia. The mine is currently operating at an annualised run rate of 9.5Mt of saleable coal. The plan is to ramp up production to 13Mtpa. Maules Creek has multiple seams each with varying depths; the inter-burden ranges from a few metres thick to greater than 30m (98ft). Due to this, Maules Creek mine is utilising truck shovel operations rather than a cast/dozer push operation.

Jan 1, 2018

By Adrian Moore, Bryan Goodwin, David Fales, David Lam

This paper describes the development of blasting protocols used to successfully create a 450m long blast fractured permeable trench in a basalt aquifer up to 20m thick, at a petrochemical facility in Australia, to enable the remediation of contaminated groundwater.

Jan 1, 2011

By John L. Didlinger

We all hate the paper work in keeping accurate blasting records. Nevertheless, have you ever thought what those records could show you? Think about it. Those records could show you vibrations, noise, and safety problems. They could show you the ratio of powder used and tons produced, the cost per foot, even help negotiations for pricing.

Jan 1, 1997

By Peter N. Calder, John N. Tuomi

The development of a successful control blasting program for an open pit iron mine in hard jointed rock is described. The objectives and mechanics of control blasting are discussed. Design and implementation procedures, which should have wide application, are given. Small diameter angle hole pre-split blasting, buffer blasting with production holes in front of pre-split lines and in front of strongly defined rock structures, and vibration control of production blasts are dealt with.

Jan 1, 1980