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By Robert Hopler

209. Nitro-glycerine is produced by the action of nitric and sulphuric acids on glycerine, and is a heavy liquid of oily appearance, of specific gravity about 1•6, varying from colourless when quite pure to a yellow or brownish yellow. It is of a very sweet taste, and without odour, and is an active poison. Mere handling of it will in most persons induce sickness and headache. It explodes when heated to about 360° F. or from shock, but in small quantities it ignites and burns with some difficulty by the mere contact of flame.

Jan 1, 2011

By Janice K. Means

The purpose of this paper is to provide the seminar attendee with: information on pipeline construction, operation and standards to better equip him (or her) to analyze the ultimate effect of blasting stress on pipelines; an introduction to the analysis of blasting effects to pipelines using the American Gas Association analysis method; and; supplemental sources useful in the analysis of blasting effects to steel pipelines, and, in particular, on natural gas pipelines.

Jan 1, 1992

By Ann Barron

For millions of people, cold weather is a fact of line – and one that can make a major challenge out of just getting to work. But for those working in the blasting industry, a number of obstacles are created when old man winter blows in. In addition to the obvious concerns regarding personal protection, Mother Nature can throw some very nasty weather at the blasting crew trying to travel with explosives products from the magazine site to the job site. As such, divers need to be familiar with cold, ice, and snow driving conditions both on and off the blast site. It’s critical to know what to expect before you leave. Keep informed of the latest weather and road conditions as they change often; it will help you make the right choice in clothing and driving habits. Remember bridges and overpasses will freeze first even in temperatures above or near the freezing mark due to the effects of wind chill. Plan to take extra time to and from the job site.

Jan 1, 2004

By E. McCullough, D. Preece, M. Ortel

Geophysical explosive charges are used in mineral resource exploration. They are detonated subsurface and radiate sonic waves into ground monitors, which detect the vibration waves and their interaction with underlying geologic strata. Geophysicists perform computer analyses of the waves reflected from the strata to determine their depth and thickness (Strobel, Berger & Schaefer, 2012). The purpose of this research is to determine how the detonating explosive charge interacts with the adjacent ground and how the induced waves propagate through the surrounding medium. Furthermore, it is necessary to optimize the location of the initiation point within the charge. Establishing both the direction and intensity of the waves will allow geoscientists to refine and optimize geophysical studies that employ explosive charges.

Jan 1, 2013

AQUILA Mining Systems Ltd., designs, develops and delivers systems for measurement, analysis, simulation, control and automation to the mining, construction and petroleum industries. The objective of current efforts by AQUILA is the continued development and refinement of computerbased systems and techniques to automatically process monitored performance data from surface blasthole drills and mining shovels, and the management and coordination of these pieces of equipment by GPS (Global Positioning Systems).

Jan 1, 1994

By Michael D. McGill, John L. Turner, Don Sieger, Doyle Newhouse

Since its introduction by Atlas Powder Company in late 1986 as a means of highwall stabilization in surface coal mines (1), applications of the basic AirDek (2) blasting technique have multiplied rapidly.

Jan 1, 1991

By Braden Lusk, Tristan Worsey, Nathan Rouse, Kyle Hall

Loading explosives up hole has challenges that are typically not seen in down hole explosive loading. Most explosives applications are not up hole. Lack of experience and technology can cause significant problems when loading explosives up hole. When results aren’t achieved, the blame is commonly put on the design when the true problems are unknown. Not knowing the cause of the problem causes drill and blast designs to be over engineered and very costly with little success. Being able to know and record key data is crucial to actually solving the problem. This paper goes over blast instrumentation that can be used to trouble shoot drill and blast problems in up hole explosives loading in underground mines. The tools and procedures used to trouble shoot include velocity of detonation recorder, borehole tracking, seismographs, and borehole camera. Each item will be discussed in detail with a case study to show the usefulness of the instrumentation. The operation discussed in the case study had issues pulling raises and had hang ups in the stope shots. These problems caused production slowdowns and costly remediation blasting that was not very successful. The case study is an underground gold mine that used modified sub-level caving with backfill as the mining method.

Jan 1, 2018

By B Mohanty, G Ludwig

A thorough assessment of development drilling and blasting practice was carried out at two underground mines at INCO operations in Thompson, Manitoba. The study showed that significant improvement in productivity can be achieved through careful selection of explosives and loading practice, and modifications of the standard blast lay-out. The analysis involved assessment of the effectiveness of various perimeter blasting methods, employing selected explosives and loading practice in both jumbo and jack-leg rounds. The blasting pattern as well as burden and spacing were varied to determine their effect on the blast results. The various types of explosives used were, pneumatically loaded ANFO, with and without detonating cord tracing, extra-strength detonating cord, and slurry and emulsion explosives with and without cord tracing. The study also dealt with various means to achieve increased rate of advance in both jumbo and jack-leg rounds. The diagnostic measurements consisted of VOD, 'burn' marks or half-barrels on perimeter wall, and blasting vibrations. The effects of geology, firing sequence, blast lay-out, and drill hole deviation on the final results were also examined. The results of the study have been shown to have very important bearing on the design of development round blasting.

Jan 1, 1998

By Donald Wagstaff, D. Scott Scovire

The Coeur Rochester Mine is the largest primary silver surface mine in North America. Throughout its 17-year life, gold and silver grades leaving the tertiary crusher have typically been, on average, slightly below the mined bench grades as determined by blast hole assays. On a project-to-date basis, this grade variance is well within industry standards. While these variances are acceptable, mine personnel continue to study ways to further minimize the grade differences. One suspected cause for lower than expected head grades are ore loss and dilution resulting from blast-induced shot movement. In regard to grade control, the underlying design principle for non-electric blasts is the generation of uniform movement of the blasted rock material. Using one or two uniform directions of initiation, ore control methods at Rochester currently include adjusting flag lines on the muckpile in an attempt to account for displacement from original, pre-blast locations. To improve upon standard non-electric blasting practices, a series of evaluation blasts using an electronic initiation system (Orica i-konTM) was conducted in the summer of 2002. The primary objective of the evaluation blasts was to design shots that would segregate the ore and waste blocks into distinct muckpiles. Due to surface delay burning front limitations, truly effective ore and waste segregation blasting is difficult to accomplish with non-electric initiation systems for all but the most basic of ore geometries. The electronic detonator evaluation blasts produced visible boundaries in post blast muckpiles, identified by troughs or low areas, that closely matched the actual locations of pre-blast ore control flag lines based on blast hole assays. By blasting the ore and waste into distinguishable piles that were flagged and excavated accordingly, it is believed that blast-induced ore loss and dilution was reduced.

Jan 1, 2004

By Raimo Vuolio

"Over the past 30 years, the Nordic countries have developed similar practices for estimating damage caused by rock blasting vibrations. However, over the last few years the risk of damage has sometimes been estimated by using international values, which have created unnecessary costs, since they are too conservative. This paper gives a proposal for Finnish blast vibration standards and a calculation model for the extent of the zones for building inspection, risk analysis, and vibration measurements. The international conclusion is that particle velocity is the best descriptor for limiting damage potential for structures. Over 900 000 vibration data recordings from 52971 blasts were collected for this paper during 1970-1989. They show that the most practical description is the vertical component of the peak particle velocity. As rock is a nonhomogeneous medium, it is hard to predict the need and scope of risk analyses, building inspection, and vibration measurements. As a large number of blasts were monitored for the recording of the peak particle velocity in several locations in Finland, and the data combined, it is possible to establish safe scaled distances for the calculation of the need and scope of risk analyses, building inspections, and vibration measurements."

Jan 1, 1991

By AN Gupta, N V. Srinivasa Rao

Initiating devices like detonators use sensitive primary explosives. Successful detonation of secondary explosive is achieved by suitable source of energy from primaries. The most widely used primaries contain toxic lead azide and lead styphnate, dinitrodiphenol or tetracine. All these primaries are very sensitive to friction, impact and heat. The handling of these chemicals is very hazardous and many accidents reported in detonator manufacturing were from these primaries only. In addition to this high sensitivity, lead azide and lead styphnate contain lead which is toxic.

Jan 1, 2014

By Steven Putt

Seismic While Drilling (SWD) is a newly developed technology in the mining industry. Improving upon Measurement While Drilling (MWD) systems, SWD measures mechanical properties of the rock at incremental depths down a blast hole at a much higher resolution. SWD is also immune to common failures and inconsistencies of MWD such as operator and drill specific variation. Seismic While Drilling records the velocity and elastic modulus of the rock with centimeter accuracy in real-time. These properties measured while drilling blastholes are then used as a proxy for density which can be used for: • High resolution geologic modeling • 3D ore control • Drill and blast optimization • Drill to mill tracking One of the distinct challenges with SWD systems is the sheer volume of information acquired. With thousands of measurements per blasthole, the data can be overwhelming for even an experienced engineer. To overcome this complex challenge, the latest cloud computing and analytics models have been simplifying and organizing the data. These newer technologies can amplify an engineer’s capability by delivering actionable insights into their drilling and blasting workflows. The paper presents new results from Datacloud during recent Seismic While Drilling trials in iron ore, metallurgical coal, and hard rock mines around the world. The measurements are compared with wireline geophysical logs, core data, drill cuttings, and conventional measurement while drilling (MWD) systems to validate the technology and show how the data can be used.

By John Capers

•The IME is the Safety and Security Association of the commercial explosives industry in the United States and Canada. •Founded in 1913 •Board of Governors •5 Standing committees- 1. Technical 2. Environmental Affairs 3. Legal Affairs 4. Safety & Health 5. Transportation & Distribution

Jan 1, 2006

By Yoshikazu Hirosaki

How big or small is the Japanese explosive market? Who are the major explosive customers? Is there any big construction project in which a large amount of explosives is expected? What is the future of the explosives industry in Japan? Is it true that there are no ANFO trucks? What is the licensing system for blasters? Is there any education system for blasters?

Jan 1, 2001

By Michael Peterson, Robert Davinroy, Robert Rapp, Gregory Hempen, David Herzog, Thomas Keevin

Fish sampling in a deep-water, high velocity, environment is extremely difficult. Conventional techniques such as electro-fishing and netting have been limited to depths generally less than 7 meters (m) and velocities below 1 meter per second (mps). The goal of our study was to sample a bendway weir field on the Mississippi River to assess the effects of the weir field on the fishery. In a bendway weir field, depths can exceed 20 m, and velocities can exceed 3 mps, making conventional sampling techniques inefficient.

Jan 1, 2002

By Raúl Mondaca Aracena

Mantoverde mine requires increasing its production level to double. EMTS - Projects performs far and near field vibration studies to make changes to the D&B design and sequences, in order to equalize the current vibration levels, applying massive blasting in its process.

Feb 1, 2020

By Saeed Karimifard, Saman Nouranian, Shahram Tafazoli, Bahram Sameti, Frank Chu, Caitlin McKinnon, Tetiana Konstantynivska, Glen Turner

Continuing blast optimization is the cornerstone of any mine-to-mill approach, and particle size analysis is a key metric for meeting blast targets to reduce overall energy consumption and operating costs. To ensure the statistical validity of particle size data, it is important to sample material frequently. In most mines and quarries, the blasted material is loaded onto haul trucks and then transferred to the crusher; measuring the particle size of each haul truck load therefore provides an adequate sampling rate. We propose a particle size analysis solution for haul trucks that does not impact current operational workflows. Using artificial intelligence (AI) and 3D imaging technology, our solution reliably localizes and identifies haul trucks as they drive by, then accurately calculates the particle size distribution of the visible material in each truck load. In this paper, we identify the challenges of designing and implementing the proposed solution and explain the strategies we employ to overcome these. We also discuss a method for boulder detection that leverages the existing deep learning architecture to significantly reduce crusher downtime caused by oversized rocks. Finally, we present field data from a trial installation. To evaluate each change made to the blast design, it is necessary to measure the effect on particle size. An accurate particle size analysis solution is therefore the first step towards optimizing blasting practices and reducing energy consumption throughout the comminution circuit.

By C Hunter, K Fedak, J P. Todoeschuck

"Perimeter wall control has a direct effect on the overall grade of any underground miningoperation. Mine management at INCO's Birchtree Mine in Thompson, Manitoba requiresmaximum perimeter wall control to meet high safety standards and to maximize nickel orerecovery. If footwall or hanging wall contacts are damaged by over_blasting, the ore maybe greatly diluted, mine productivity may be reduced and safety problems can arise.Excessive or poorly distributed explosive energy is a major cause of damage to the hostwall rock."

Jan 1, 1993

By Jorge Cárdenas, Alejandro Luna

In mining simulation for fragmentation results prediction is of utmost importance to study feasibility, ensure safety, and estimate the correct use of resources in drilling an explosive to meet requirements and avoid excessive usage. One critical case is fragmentation prediction, developed through models. Developing a fragmentation model in a mining unit aims to control blasting results to align theoretical and real data and improve correlation. Therefore, it is essential to collect post-blast fragmentation data, organize it, and systematically process it to develop a suitable model that meets variable requirements. Using a robust system of equations, this model should generate the required results with minimal variability between simulation and actual results. Additionally, this model must be adaptive to reduce this variability. Studying the most known and used models in mining resulted in our work correlating Cunningham 2006, Swebrec, and CZM models. Thus, the Simfrag model was created, presenting a robust foundation and combining the most notable advantages of the aforementioned models.

Jan 21, 2025

By W. J. Birch, R. Farnfield, G. D. Rangel-Sharp

It is widely recognised that complaints from members of the public relating to blasting operations are related to both ground vibration and air overpressure. It is also known that a complaint is more likely to be generated if the person is inside of a structure at the time of the blast. Reports relating to such complaints often refer to ‘noise’ inside the structure with terms like ‘rattling’ commonly being employed. Such acoustic response is widely perceived within the blasting industry to be directly related to high levels of air overpressure although there appears to have been very little research carried out specifically related to this effect.

Jan 1, 2007