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By Hapsari Rosa, Ross Cowie

Conventional blasting activities in the mining process use various types of explosives, with the primary raw materials being Ammonium Nitrate and diesel fuel. The quality and specifications of the two raw materials significantly affect the performance of explosives. One program from the Indonesian Ministry of Energy and Mineral Resources requires mixing 30% Bio Diesel 30 with 70% diesel fuel oil in several industrial sectors, including mining, to reduce greenhouse gas emissions and stabilize CPO prices. This program aims very well for environmental sustainability and the palm oil business. However, it turns out that this change impacts the performance and results of the blasting process in the mining industry, which is the appearance of fumes. This paper will discuss the tests carried out in the laboratory on Bio Diesel 30, the explosive products used, and rock samples were taken from a mine in East Java, Indonesia. The aim is to determine what factors can cause fumes utilizing a mixture of Bio Diesel 30 with pure diesel fuel. The parameters tested were visual differences, infrared spectrometry, density and viscosity, surface tension and contact angle for Bio Diesel 30, stability test for explosives, and the SEM-EDS method for rock samples.

Feb 6, 2023

By W. Sharkey Bowers

This study was undertaken in order to determine a conservative estimate of the attenuation rate of vibrations through the shallow limestone in South Florida due to quarry blasting.

Feb 1, 2020

By Lyall Workman

New mines are frequently located at altitudes above 3,000 meters (10,000 ft.). Drill selection must take the altitude effects into account, to insure high productivity and good bit life. In particular, compressors must be sized differently than for low altitude operation. A larger compressor is required to deliver adequate air to the bottom of the blasthole. Many drills in remote locations use diesel engines as the prime mover. Altitude effects on engine performance should also be considered.

Jan 1, 2007

By Javier Illanes, Felipe Moroni

In recent years, implementation of Artificial Intelligence and Machine Learning model technology has gained ground in almost every aspect of human activities. The mining industry has not been foreign to these applications, with advantages including the creation of new optimization methods and the elimination of repetitive tasks. Those applications have been implemented in multiple operative areas, from preventive conveyor belt maintenance to energy optimization for minimizing environmental impact. The blasting process aims to use the energy liberated by the detonation of explosives to break the rock mass according to specifications that facilitate the comminution process. To optimize this process, the energy delivered must correspond to the necessary amount to exceed the tensional and compressional resistance of the rock mass. If the energy applied is insufficient, the rock will not reach the desired fragmentation level and the processing plant may incur additional costs. On the other hand, if the energy level required is exceeded, we incur increased blasting costs that correspond to excess explosive used. Optimization of this aspect of the mining process has major impact in the processing chain reflected in lower costs, efficient resources consumption and environmental impact. The Design for Outcome technology (DfO), developed by Orica, is used to characterize the rock mass in detail to classify, borehole by borehole, the rock mass relative hardness to deliver the adequate energy level to achieve optimal fragmentation. This technology uses information collected by drill sensors, producing data typically referred to as Measure While Drilling (MWD) data to classify the rock mass into domains that can later be used to apply optimal blast designs. In DfO, the data flow is fully automated, starting with the data produced by the drilling system and uploaded to the cloud, which is then domained using Machine Learning (ML) techniques, and then published for consumption using a web interface. Automated explosives loading rules are then generated for each rock mass domain, ensuring that for each borehole, the adequate explosive energy is delivered to achieve the desired fragmentation results with unprecedented accuracy. The application of machine learning techniques allows us to optimize the blasting process results by leveraging a deeper understanding of the rock mass. Applying these optimization techniques, we obtain considerable economic benefits, decrease resources consumption, and achieve a more sustainable mining operation. The application of DfO in a Chilean mining operation allowed the characterization of their rock mass into four domains and established specific explosive loading rules for each one. A 60kUSD reduction in explosives cost was achieved during the test period, while maintaining the desired fragmentation results and expected dig rate. These outcomes were the result of a comparison between the blasting costs used applying the technology mentioned above and a “traditional” classification of the rock mass with the corresponding blasting practices.

Jan 21, 2025

By Francisco Sena Leite, Raquel Sobral, Vinicius Gouveia de Miranda, Céu Jesus

"This document investigates a newly developed technique with the objective of improving terrain triangulation models (horizontal/sub-horizontal and vertical/sub-vertical terrains), mainly blast free faces. The algorithm uses multi-linear regressions to generate the best point cloud projection plane by applying the residues modulus minimization so as to create the finest 3D triangulation model. A change of base is required to create a new set of coordinate axis and generate completely new projection planes. The projection plane residue analysis is inferred in order to avoid or reduce the outlier points. The dataset is composed of 12 terrain models obtained from photogrammetry and a 3D Laser equipment thatgenerates georeferenced cloud points. This new technique is validated by the analysis of the obtainedcritical burden by the improvement of the general aspect view of the terrains and the capacity of outlier’s detection. The result and the quality of the algorithm demonstrates the improvement in the triangulation mesh, reducing errors in the calculation of over/under burden, free face volumes, cavities and, therefore, in the estimations of clearance/safety distances."

Jan 1, 2017

By David G. Paton

"Electromagnetic surveys were conducted at the BXL Bulk Explosives Limited Mixing Plant andsurrounding area to characterize runoff from the site and possible impacts of salinity. The BXL Plant is located at the edge of a depressional area and any escape of soluble ions, such as nitrates, would have ended up in the slough to the west of the plant. Two electromagnetic (EM) instruments were used in the survey. A Geonics EM 3 1 was used in October 1997 and in June 1998, a new multifrequency instrument, a GSSI GEM 300 was also tested. Both instruments were individually mounted on a plastic sled with Teflon runners and towed with an ATV quad. Position was determined using a Trimble Pro XL global positioning system (GPS) with a real time correction mode Landstar receiver for an accuracy of about *l m. Both GPS and EM instruments were set to collect data at 1 second intervals. The quadrature maps for both instruments showed essentially the same information, namely of very high conductivity, appearing to emanate from the mixing plant. The levels of conductivity were highest where the saline water appeared to pool, at the southern end of the slough. Soil sampling locations were identified from the EM maps and navigated to using the real time GPS. Composite samples were collected by hand using a Dutch auger, from two locations, in increments of O-1 5, 15-30, 30-60 and 60- 90 cm. The analysis of the soil samples indicated a complete absence of nitrate or ammonium ions; the major anion was sulphate, indicating naturally saline subsoil conditions. The GEM 300 made the collection of data more efficient, as only one pass was required to collect the data from four depth intervals. The EM survey combined with the real time GPS allowed rapid characterization of the site with respect to soil salinity and proved to be cost-effective for Phase l/ Phase 2 site assessments and targeting sampling locations."

Jan 1, 1999

By Quian Liu

The problem of cross-hole explosive malfunctioning in rock blasting (including sympathetic detonation, desensitization and cut-offs) is a function of delay and spacing in a blast which should be designed to avoid such occurrences. On a delay-spacing chart, the phenomenon of explosive malfunctioning is explained by dividing the chart into different regions, while the shape and size of each region could vary from one explosive to the other. Over seventy blasts have been carried out at the CANMET Experimental Mine to identify the malfunctioning characteristics of specific emulsion, water-gel and dynamite explosives. In each experiment, two parallel blastholes, 32 mm in diameter and 1.7 m deep, were drilled downwards in an underground drift.

Jan 1, 1994

By Brendan O'Reilly, Outokumpu Zinc, Geoff J. Johnston, S Durucan

Historically vibration monitoring has dealt primarily with surface blasting or "near field" monitoring of underground blasts. The Situation at Tara Mines is different, blasting occurs up to 400m underground, with a number of blasts occurring daily and occasionally with residential properties directly above the blasting site. Tara Mines, due to both its location (1.5 km from the rural town of Navan) and stringent planning conditions have always had to monitor, carefully plan and control the levels of vibration from blasting. The statutory vibration limit at Tara allows a maximum peak particle velocity of 7.62 mm/s with no frequency limitations. Levels of vibration have been monitored continuously since mining operations began in 1972.

Jan 1, 1994

By Kunihisa Katsuyama, Yuji Ogata, Yuji Wada

Test blasting was carried out to study the flying characteristics of rock mass caused in bench blasting. The quantity of explosives was increased from 7.6kg to 9.1kg and the Minimum burden was changed from 131mm to 451mm. The effect of condition for the characteristics of fly rock were considered. The fly rock was observed using the high-speed camera and video to study the flying characteristics of the rock mass caused in the bench blasting. Numerical simulation of fly rock was carried out using DDA (Discontinuous Deformation Analysis) method. It was clear that the DDA method can be applied in the simulation of fly rock caused in bench blasting.

Jan 1, 1997

By Lindsay Wade, Peter Dare-Bryan

Benches in surface mines often contain known areas of ore and known areas of waste, which must be mined selectively. When rock is blasted it not only fragments but is also physically, and non-uniformly, moved. Risks therefore exist of ore being lost if treated as waste and of mill feed being diluted by waste. Both possibilities carry serious fmancial implications.

Jan 1, 2001

By M. Oguz Ozkazanc, Gulsev Uyar Aldas

Because of its safety, being easy to handle, relatively inexpensive and containing a lot of energy, ANFO is the most popular and widely used explosive in Turkey as well as other countries in the world. According to change dated May 14th 1999 on the regulation 87/12028 related with explosives, blasters are not allowed to mix ammonium nitrate and fuel oil in the tield to make ANFO. Instead of this, they have been forced to use the ready ANFO prepared by explosive producer firms. As a result of this obligation, the use of technical nitrate for agricultural purpose and mixing AN and fuel oil in unsuitable conditions have been prevented. Indeed, wrong mixture means waste of energy and money.

Jan 1, 2001

By Terry Matts, Bruce Ripley, Clark Fletcher, Paul Rapp, Stan Holtby, Jim Dent

The Stave Falls Project of BC Hydro, situated 65km east of Vancouver, BC, Canada, involved the construction of a new two-unit 9OMW hydro-electric facility to replace an existing powerhouse. The final phase of the intake excavation consisted of a plug blast to break the channel through into Stave Lake. The plug consisted of a rock and till wall topped with a fill cofferdam, about 51m wide and between 8 and 12m high. Total rock volume was approximately 2600m3, overlaid with about 4600m3 of till/fill. This paper describes the methodology and practical techniques used in planning and loading the blast, and the precautions taken to protect the new and existing structures and equipment. Blasting of the plug by the normal method using downholes would have required the placing of extra fill and much drilling through casing, so the contractor made the decision to drill horizontal holes from the dry, downstream side. Because of poor rock conditions, all 183 holes had to be drilled oversize at 3.5” dia. and fitted with 2.5” id. plastic pipes to keep them open. Hole lengths ranged from 2.5 to 18rn, with a pattern of 1.5m spacing and l.Om burden (with the holes slightly fanned vertically). Because of significant water exposure, a film-packaged emulsion explosive was used, placed using a pneumatic cartridge loader for maximum borehole compaction. The powder factor averaged 1.3kg/m3 (2.21bs/yd3, rock only). An initiation system of combination surface/downhole delay shocktube units was employed, with double and triple redundancy. The maximum number of holes firing in any 8ms window was limited to three (to minimize vibration), while the whole sequence was fully activated before the first hole fired. All shocktube connections were secured and covered over at the foot of the rockface before flooding the excavation downstream of the plug prior to the shot, To protect the powerhouse gates from hydraulic shock, all hole collars were grouted and an air curtain was provided. The blast was completely successful. A maximum vertical displacement of 6m was recorded, but no flyrock was evident. Readings for peak over-pressure and vibration were well below the allowed limits. Mucking proved to be easy, with fine fragmentation, full pull, and no tights.

Jan 1, 2000

By Thomas M. Keevin, Gregory L. Hempen

A study was conducted to measure underwater pressures associated with confined borehole shooting used to remove rock for The Kill Van Kull Deepening Project, U.S. Army Corps of Engineers, New York District. A major natural-resource-agency concern was the potential for fish mortality during explosive rock removal. Currently, fish mortality models are based on testing programs that exposed captured organisms to open-water blasts. Natural resource agencies, without in-house explosive engineering expertise, generally are not familiar with the physical properties of blasting underwater. Confined shots are most often used for demolition and rock removal underwater. Pressure amplitudes from confined blasts are significantly reduced as compared to open-water blasts that, are commonly used for fish testing The duties of natural resource agencies are made even more difficult by the lack of published data on pressures associated with confined blasting. As a result, explosive weights for confined shots mistakenly have been used to run mortality models that were developed using open-water blast pressure data. This study was conducted to collect pressure measurements during rock removal for the KVK deepening project and compare those data with computed peak pressures for open-water explosions.

Jan 1, 2005

By Paul Klaric, Nicholas Bodley

Every blasting engineer or professional can attest to the age-old conundrum of obtaining accurate hole information on a large scale prior to loading explosive charges in a blast hole. Even though the benefits of QA/QC are well known and documented and are becoming increasingly important when digitizing and automating mining operations, the QA/QC process itself has not changed significantly over generations. The current methods where operators deploy measuring tapes of variable standards recording their subjective assessment of hole length on a paper blast map or manually transcribing to a tablet, are unreliable and non-auditable. Additionally, the process in its current form is time intensive, obtaining only moderate results and benefits, making it difficult or impossible to resource in today’s tight labour markets. Often only two data points, depth, and water presence, are captured when visiting the hole resulting in a high cost per bit of data. For these reasons, the process is seldom done on a large scale, let alone integrated. The QA/QC process in its current shape is a gap that will need to be addressed if autonomous blasting and mining is to become a reality.

Feb 6, 2023

By R. F. Favreau, Patrice Favreau

In many quarries and construction sites visited by the authors over the last 50 years, the latter have observed muck piles from blasting with explosives, which included numerous large blocks, in some cases of dimensions larger than the input to the crusher. The names of these sites cannot be given in the article because the owners insist that data obtained on such visits be kept confidential. Often the blasters felt that the natural fissures in the rock would compensate for the use of a low powder factor, and they asked the authors to explain why such blocks were present. A detailed analysis of the situation often indicated that the cause of the blocks is that explained by figures such as 6 and 7 below in the article.

Jan 1, 2018

By Maja Franjic, Ian Tolliday, Chris Collins, James Wiltshire

Ammonium Nitrate Emulsions (ANE) are a large segment of the explosives market for the mining industry. These emulsions are generally designed to be very stable but when breakdown does occur, removal of the resulting thick, crystallized material can be difficult, hazardous, time consuming and costly. A heavily crystallized emulsion cannot be pumped, so manual removal often becomes necessary. Buildup of semi-solid layers of crystallized emulsion can occur in bulk storage tanks or in truck compartments. In these situations, a manual cleanup involving hazardous confined-space entry and a significant amount of downtime is usually required. Once the crystallized emulsion is removed from the equipment, there is very expensive disposal of the resultant waste via a licensed trade-waste company. A much more desirable solution for dealing with waste emulsion is to completely break the emulsion, allowing the oxidizer and fuel phases to separate into two distinct layers. These layers would then be readily pumpable and could be disposed of much more economically. It may even be possible that the separated oxidizer phase could be repurposed as fertilizer and the fuel phase could be used to manufacture granular ANFO explosives. There are some existing products on the market for breaking emulsion explosives, but these generally need a high degree of mixing into the emulsion to achieve adequate breakdown. The aim of this study was to identify surfactants systems (demulsifiers) capable of effectively breaking a range of waste emulsions with minimized agitation. This paper describes the development and performance testing of novel demulsifier products. The test work involved a comprehensive series of laboratory screening tests, where the demulsifier formulations were optimized. A highly efficient formulation was identified, and field trials were conducted on real world, full-scale waste emulsions. Results will be presented that demonstrate a viable solution for the disposal, and potential re-use, of waste ANE in the explosives industry.

Jan 21, 2025

By R. Jacob Cefalo, Miguel Valenzuela

The modern drill and blast engineer operates in an environment often rich with data from drilling data and blast designs vs. actuals to fragmentation distributions and vibration records. Despite this abundance, much of the information generated remains underutilized, often collected as a matter of routine rather than for a means to an end. This paper explores how artificial intelligence (AI) can bridge that gap, transforming raw operational information into actionable insights that lead to more consistent and optimized blasting outcomes. Through AI-driven analysis of drilling logs, burden and spacing measurements in design vs. actual, fragmentation distributions, and vibration records, we can identify hidden patterns and correlations that traditional analytics overlook or that we may not be aware of. These insights enable engineers to proactively adjust designs and loading strategies, ultimately improving performance aspects such as improving fragmentation, minimizing ground vibration, and lowering overall operational costs. The paper examines the industry's reliance on lagging indicators, such as post-blast fragmentation surveys or actual powder factors, and suggests the need to shift toward leading indicators like real-time drill data monitoring and predictive fragmentation modeling. Utilizing AI to forecast outcomes before a blast is carried out allows engineers to take corrective actions early in the process, thereby creating a feedback loop that continuously improves performance. This integration of AI into drilling and blasting practices marks a pivotal opportunity for the explosives engineering field to evolve from reactive to predictive methodologies unlocking a new level of operational intelligence and value creation.

Jan 26, 2026

By Dale S. Preece, Ruilin Yang

Shock wave physics is an important part of air-deck behavior since the bulk explosives in the column impart a shock into the air-deck where the air shock then passes through the air-deck at a rapidly attenuating velocity. Through both high-fidelity modeling and shock physics theory it is shown that the resulting pressure in the air-deck is two orders of magnitude less than the detonation pressure of the explosive. The induced air blast reflects from the bottom of the borehole and this reflected pressure, even though doubled, is still approximately two orders of magnitude less than the detonation pressure. Air-shocks will ring back and forth in the air-deck for a few tens of milliseconds while the adjacent explosive column(s) are detonating. Transmission of the initial shock through the air along with reflections is an intensive energy consuming process. Energy balance results in shock heating of the air and a temperature increase. However, the increased temperature of the air is also orders of magnitude less than that of the explosive detonation products immediately behind the detonation front. Replacing high energy explosives with zero energy air-decks in a blasthole will always have a negative impact on the adjacent rock fragmentation and movement.

Jan 1, 2016

By Stephan Iversan, Janae Singer

High resolution seismic refraction tomography has proved to be a useful tool to effectively estimate depth of blast induced damage in rock. Excavation blast damage can be as shallow as 1 to 2m (3 to 7ft) and requires resolution at a fraction of a meter for effective imaging. We used an accelerometer with flat frequency response to 1000Hz to record data at spacings of approximately 0.25 to 0.5m (0.8 to 1.6ft) along mine walls. The resulting tomograms of P-wave velocity show low velocity zones which we interpret as residual fracturing from blasting. Experiments on a concrete test block and at two underground mine locations give results that are consistent with fractured rock transitioning to competent rock.

Jan 1, 2009

By Donald Jonson

Stockholm’s Northern Link, currently Europe’s largest urban road tunnel project, will be about 5 km long from west to east. Running through two separate, mostly parallel tunnels, each with 2-4 lanes, the complex will include numerous entries and exits, as well as a major branch to the north. The total length of tunnel will be 11 km, of which 9 km will be in rock. Over million m3 of rock will be blasted. The Northern Link will open to traffic in 2015. After a 10-year stop to deal with environmental questions regarding Ekoparken, Stockholm’s unique “national city park”, the Northern Link project in the Swedish capital was restarted in the autumn of 2006, with the construction of five works-access tunnels.

Jan 1, 2009