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By Claude Cunningham

AEL has been developing electronic detonators continuously since 1986. It launched its first system for opencast mining in 1993, and now has two distinct product lines. The path has not been without great difficulty, but the determination to persevere was always buoyed by the strong encouragement of customers who experienced the transformed blasting results, as well as a clear vision of the enormous intrinsic value of the concept. The path of growth to dominant global supplier is traced through the separate application channels of coal stripping, quarrying, massive mining, opencast mining and narrow reef mining, to the first allelectronic detonator demolition blast in June 2001. Reasons for the slow coming to market of this highly desirable concept, which often coincide with reasons for the demise of various other systems, include the difficulty of safely mating electronics and explosives in a low cost environment; the extreme difficulties of achieving proper connection under mining conditions; the rapid rate of evolution of the technology, and the safety concerns raised by various accidents and incidents along the way. ED.s are now established as the way forward and are set to displace other systems in all serious applications. There is place for both programmable and pre-set delay systems.

Jan 1, 2002

By He Guangyi

Combining living examples, the paper introduces the controlled chamber standing shot of more than 3000t explosives initiated at one time with Nonel under complicated circumstances and the experience obtained to keep environment safe and favour mechanical rock cleaning.

Jan 1, 1998

By D. Pickering, R. Wharton

The deadline for meeting legal requirements relating to the sale of explosives in the European Union was 1 January 2003. The paper examines the range of materials that have already been certified by the different Explosives Notified Bodies as well as recent national and European Commission decisions relating to this work. The implications of enlargement of the European Union are also discussed as is the future role of the Great Britain Explosives Notified Body in certification and assessment.

Jan 1, 2003

By Richard E. Danell

"Blasting is a principal step in the surface mining process for breaking and, in the case of overburdencasting, moving rocks and minerals. As many surface mines are coming to the end of theiroperational life, blasting can once again play an important role through the earthmoving operationsrequired to rehabilitate the minesite. Since blasting is such an energetic and destructive process, itis difficult initially to envisage its use in rehabilitation. However, blasting has found applications inmany civil engineering projects aimed at rehabilitation, including well digging, channelling and soilcompaction. For surface mine rehabilitation, the main purpose of earthmoving operations is toproduce a stable landfonn that will sustain revegetation. In particular, blasting can be applied toreducing the slope of steep walls left by quarrying and open pit mining through a modified form ofthe overburden casting technique. Blasting can also be applied to breaking up pit floors andbenches to speed and improve revegetation of these areas (subsoiling)."

Jan 1, 1994

By Ivan Carrasco, Benjamin Cebrian

Mining companies have traditionally organized their structure around a scheme easy to manage: Mining Department and Mill Department. In a challenging landscape for mining, with decreasing grades, increasing rock hardness and more expensive energy, this way to organize departments has resulted in internal disputes and often contradictory targets between both mine and mill. These compete for individual, separated budgets whose Key Performance Indexes often damage each other’s output. The results are increased total production costs and reduction of profits. Some companies have completed the first step in eliminating these inefficiencies by creating Fragmentation Engineers and Fragmentation Superintendents. With all the knowledge available on the overall fragmentation process and costs, in this document an overhaul of the traditional management structure is proposed. Is a step further Mine-to-mill and mine-to-leach programs. Since comminution is the most expensive step of the mineral exploitation, it should be taken as a whole, not divided into competing departments. Thus, mining departments should be re-grouped into: transportation, fragmentation and flotation.

Jan 1, 2014

By Des Bolton

With the introduction of Cast Blasting techniques, field controls of Drilling & Blasting operations became more important. New drills were purchased which were equipped with sophisticated instrumentation and more accurate drilling plans were required. Concurrently a decision had to be made on the replacement of borehole logging equipment owned by the mine. The use of a contractor to log blast boreholes was eventually decided upon, the information gained from this operation is used in the short-term drill and blast planning and may also be used to assist in the coaling operation if density I quality correlations prove acceptable.

Jan 1, 1994

By G. R. Adhikari

Step 4: Selection of explosives and initiation system Various types of explosives are manufactured in India and a wide choice is available among them that include nitroglycerin based explosives, slurries, emulsions, ANFO (ammonium nitrate mixed with fuel oil) and heavy ANFO. The choice is also available between cartridged and bulk loading systems. In Indian mines, much importance is unduly given to the cost of explosives alone which is not conducive to optimization of blast design parameters. The concept of energy per meter of blasthole and the way in which the total explosive energy is partitioned between shock and heave is not considered in the prevailing practices. Besides, very little efforts are made to objectively evaluate the performance of explosives for a given site condition. Tailoring explosives is limited to changing the density of the bulk explosives. Cartridged explosives are still being extensively used in large operations where bulk explosives should be the preferred choice.

Jan 1, 2002

By Larry Schneider

"0 ne of the incentives that led to the development of non-electric shock tube initiation systems was the desire within the industry to improve detonator safety. And to the extent that nonelectric initiators are immune to the hazards of stray current and radio frequency energy found on normal blast sites, an advancement in safety has been accomplished. However, as a cautionary note, it is important to realize that there are still many hazards associated with any initiation system. While some of these hazards may differ from those associated with electric detonators, others are identical to those associated with any type of initiation system. For instance, contrary to what some uninformedblasters may believe, lightning remains a hazard when using nonelectric initiation as well as electric initiation."

Jan 1, 1995

By Kenneth Etschlager

The ISEE Blast Vibration and Seismograph Section provides a forum for the discussion of issues related to vibration and noise from mine, quarry and construction blasting. The section began as a Technical committee in 1995 to promote the accuracy of blasting seismographs. Currently five subcommittees exist within the section: Seismograph Standards; Seismograph Testing and Calibration; Vibration Limits, Technical; Vibration Regulations; and Program and Communications. Foremost, the Seismograph Standards section wrote the first two technical standards adopted by the ISEE. The historical accomplishments, current activities and objectives of the section are discussed.

Jan 1, 2003

By Wes Bender

Considering the current interest in Global Positioning System (GPS) usage, it might be timely to look at a more efficient means of utilizing these instruments. The GPS system currently utilizes 28 satellites (4 are spares) circling the earth in an inclined orbit. Normally at least six satellites are within your area of reception at any given time. The satellites broadcast an extremely accurate time signal and an almanac containing all the satellites’ orbital data. This information is updated regularly as the satellites circle the earth. Your GPS receiver, once it has picked up one satellite’s broadcast, can then determine which other satellites should be available for plotting.

Jan 1, 2002

By Tom Watts

The practice of pumping bulk blasting agents is regulated by many agencies around the world. The explosives manufacturers have done an excellent job of hazard and operability studies allowing criteria to be established for the safe pumping of water based blasting agents. The challenge of a Bulk Trucks or Mobile Manufacturing Units (MMUs) manufacturer is to take the objectives of the regulatory agencies and the explosives manufacturers and responsibly design and build MMUs that are safe, compliant, and cost effective without compromising serviceability.

Jan 1, 2011

By Victor C. Bryan

One of the most sought after answers in any consideration of blasting activities relative to mines and quarries is how to safely and efficiently use explosives. While that discussion might be relatively straightfonvard in a “site specific” situation. it becomes more complex when viewed from a broad geographic perspective. Such is the case in considering the operations of one United States producer of crushed stone with surface and underground mines spread over a thirteen state area. Differing geologic environments set conditions that dictate to the blaster as now specifically to get optimum results from the blast hole. This treatise is a discussion of the various methods, materials, and principles used in conducting such blasting operations.

Jan 1, 1991

By R. Reed Skaggs, William Gault, Douglas Kooker

Both armored personnel carriers and light combat vehicles are increasingly vulnerable to a variety of highly lethal antitank land mines. As a result, there is a need for modeling and understanding the interaction of mine blast products with respect to the resulting loading and damage mechanisms inflicted by explosive blast and impact on vehicle structures. However, the mechanics of blast soil interactions are still poorly understood. The objective of this investigation is to computationally simulate a series of experimental buried mine explosions in saturated sand soil -- over a wide range of scale – and compare the predictions of blast loading to data. Small scale tests have recently been conducted at the University of Maryland with a few grams of RDX acting against an aluminum plate, while recent full-scale tests at ARL involve several kilograms of TNT against 12,500 kg of RHA. The ARL measurements reported here are based on the Vertical Impulse Measurement Fixture (VIMF) facility, a structural mechanical device that responds to blast loading by measuring the vertical displacement of a fixed mass vertical guide rail, which is a direct measure of the imparted impulse. CTH predictions for vertical momentum of the target plate are within 60 – 80 % of the reported impulse data for this wide ranging set of tests. One of the comparisons, however, suggests that the TNT charge in a particular VIMF test may not have fully reacted.

Jan 1, 2005

By ATF Publications

The following is a summary of the changes that were incorporated into the new Federal Explosives Regulations, 27 CFR Part 55, dated 9/2000. However, in light of the recent events of September 2001, additional changes in the Federal Explosives Laws and Regulations may be forthcoming. The nature and extent of any such potential changes are impossible to gauge at this time. However, this synopsis of the changes contained in the September 2000 Orange Book, ATF P 5400.7 was current at the time of this writing. Any questions regarding this paper should be directed to the Public Safety Branch in ATF Headquarters in Washington, D.C.

Jan 1, 2002

By R. F. Favreau, P. Favreau

Rock excavation is the first process in the cycle of operation of a mine, and efficient blasting is paramount to the profitability of the mine. The traditional way to design blasts has been by trial and error, based on the experience of the designer. This is probably the only important engineering practice which continues to be done without a precise engineering technique. The efficiency of most other mine processes has been improved by the use of high-tech, while a majority of blast design has not yet profited from the advantages of the computer. However, with the advent of the high-tech blast simulator Blaspa, it has become possible to design the parameters of the blast according to normal engineering practices. Over the last 50 years, the chemical and physical mechanisms which occur during a blast have come to be identified; they are reviewed in section B. Although these mechanisms are complex, they have nevertheless been expressed in terms of mathematical equations which have been assembled together in the computer to create the blast model Blaspa.

Jan 1, 2002

By Christopher Jon Preston, Troy Williams, Daniel Roy

There has been significant progress made with narrow vein gold mines in which a second option for crushing has begun to attract attention. To ensure the profitability of a mine that has based its economics on the absence of a crusher station, more than just best blasting practices are required. Using a blasting operation itself as a primary crusher would undoubtedly save enormous capital costs as well as eliminate some of the costs of crushing ore with the result that considerable savings might be realized. The challenge would be to define the conditions necessary to make this type of operation feasible by providing consistent blasting methods that result in a significant paradigm shift with respect to both blasting and current underground crushing methods. A break model has been developed and applied as a technique in designing blasting patterns based on a unit charge blasting geometry and stress reflection from free faces. There are four components to this model and these are 1) unit charge, 2) thermodynamic/energy, 3) stress reflection, and 4) radial break. Some important changes in timing between holes and rows based on rock properties and the percentage of burden moved were also used. On-site testing at a narrow vein gold mine in Quebec Canada, provided measured parameters for the model. No underground crusher was planned - relying only on the fragmentation profile generated by ring blasting. The specification for muck was that the fragmentation profile needed to be 100% < 400 mm (16 in) with no overbreak - with dilution less

Jan 1, 2019

By Kai Nielsen

The paper presents the results of several industrial and laboratory blasting, crushing and grinding tests and experiments investigating how blasting can influence the subsequent crushing and grinding operations. The paper also describes how these results can be used in order to optimize the entire comminution process from solid ore to a semifinished or marketable product. Two cases are presented, one looking at the processing of fine grained taconite ore, and the other discussing the processing of raw milling product for cement burning.

Jan 1, 1998

By Paulo C. Fernández A, Sergio Matamala V, Claudio C. Gajardo, Christian A. Rees P

In fragmentation processes in open-pit mining, it has been observed that there are many opportunities for improvement if greater control of ore displacement in blasting is achieved, reducing the percentage of mixing between ore and waste material (dilution) through the integration of new technologies that allow its quantification and optimization of extraction polygons. This work investigates the relevance of the initiation sequence and direction of displacement in blasting in relation to ore dilution and the potential benefits of process optimization. A three-dimensional modeling tool was used to evaluate movement control optimizing the extraction zone based on the maximization of ore recovery. The study was made by iterating different scenarios, by varying only the initiation sequence and inter-hole delays. To validate the displacement simulation, a total of 10 blasts were carried out for calibration, obtaining a level of agreement between the simulation surface and the actual topographic survey of 80% or higher. The analysis included horizontal and vertical displacement, quantification of swell and dilution within extraction polygons for different scenarios, and informed decision-making based on ore control. The results clearly indicate that by modifying the blast initiation sequence, greater control over dilution in ore/waste transition areas is achieved, thus optimizing the recovery of the planned material and maximizing the ore grade. The use of this type of simulation tools allows for the generation of extraction strategies based on the value of the polygon, unnecessary displacements in the free face, optimal loading fronts, etc., maximizing the recovery of ore and stockpile material, complying with the planned tonnage and ore grade for each extraction polygon, delivering added value to the chain and emphasizing the importance of adding new technologies to the mining industry that allow for the optimization of processes to maximize profits.

Jan 26, 2026

By Sunil Vytla, Akash Adhikari, Purushotham Tukkaraja

Blasting operations produces gases and fumes that may be toxic or non-toxic in nature. A detonation of commercial explosives such as ANFO, emulsion, and dynamite would ideally produce only nontoxic products such as steam (H2O), carbon dioxide (CO2) and nitrogen (N2). However, in the real world, the detonation of explosives produces toxic products such as nitrogen dioxide (NO2), nitric oxide (NO) and carbon monoxide (CO). The focus of this study is the blast fumes entrapped in the muckpile. Fume clearance and workplace re-entry time studies performed in the past have overlooked the toxic gases entrapped in the muckpile. Studies show that as much as 60% to 70% of the fumes or gases produced during blasting underground can remain entrapped in the adjacent rock mass or in the muckpile. The toxic fumes trapped inside the muckpile are slowly released and could be fully uncovered during the mucking process. Exposure to these gases or fumes is hazardous to mine workers. In this study, author have analyzed the nature of fume flow, i.e. accurately predicting where and how the fumes flow after an underground development/tunnel blast. This will help in determining i) precise re-entry times for the workers ii) rate and direction of the fume flow. Computational Fluid Dynamics (CFD), a mathematical simulation technique that predicts fluid dynamics phenomena is used for this purpose. CFD is preferred over physical models because it is inexpensive, once the accuracy is established, a wide range of scenarios can be simulated quickly, and the toxic gas flow patterns through underground openings can be analyzed efficiently. For this study, CFD is performed using SC/Tetra software owned by MSC software company.

By Marlyn King, Kevin Peterson

Power Decks are voids created in the bottom of the borehole through the use of a suspended Super Plug. Explosive energy is started downward at initiation creating high pressures which find relief at the comers of the borehole cylinder in the bottom of the hole. This relief creates a horizontal break to the neighboring boreholes - the same effect as presplitting. This “presplit” represents a change of mass to.the explosive energy,and it is reflected upward in the more efficient form of tensile waves. This provides better use of the explosive energy than compression waves. This technique has created a new way of looking at the ways that explosive energy is transported through the rock mass.

Jan 1, 2002