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By John Manka

Emulsion explosives consist of an aqueous oxidizer phase, a fuel phase, and an emulsifier. The ability to use lower-cost sources for any of these raw materials presents an obvious economic advantage to emulsion manufacturers. This paper focuses on using low cost waste drain oils as the fuel phase in emulsion explosive applications. Laboratory studies showed that emulsions made from waste drain oils and agricultural ammonium nitrate prills were usable for emulsion explosives though their shear stability was weak. Customer field results proved that waste crankcase drain oil could replace half of the virgin diesel fuel in emulsion explosives to make an effective emulsion explosive product with a very low cost.

Jan 1, 2003

By Catherine T. Aimone-Martin, Brent Meins

Blast vibration monitoring for buried pipelines is typically conducted at the ground surface with a shallowly buried geophone. In many jurisdictions across the U.S., blast-related vibration limits set for pipelines are dictated by surface measurements and do not consider the significant reduction of PPV amplitudes acting on the pipe at depth. This study involved a vertical array of geophones deployed in drilled holes at two blasting sites of the Loop 202 South Mountain Freeway construction project in Phoenix, Arizona. City of Phoenix pipeline engineers were concerned that blasting would damage an aged 48-inch (122 cm) prestressed concrete cylinder pipe (PCCP) that serviced water for South Phoenix

Jan 1, 2019

By Peter Dare-Bryan, Will Hunt, Lee Julian

It is well-known that blasting has an economic effect on grade control activities. However, until recently, methods did not exist for measuring the grade control value change caused by the blast. Rules of thumb were the best method to minimize ore loss and dilution, as simulation has been traditionally constrained by time and computer power. Even with these rules followed, an extensive study performed on over 150 blasts showed that the value change caused by the blasts followed a normal distribution – some blasts created value, and some blasts destroyed value. The question naturally asked was “How can we ensure the blast designs are optimized to create value?” Recent advancements in computer power have enabled real-time blasting simulations that create post-blast grade control models before the blast is fired. Understanding what will happen before it happens allows blasters and grade control personnel to iterate designs, searching for the highest value achievable.

Feb 6, 2023

By Francisco Sena Leite, Thomas Palangio, Vinicius Miranda

With an increasing pressure to find efficiencies in the mining industry, operations are looking for continuous improvement tools to validate blasting procedures, a crucial and often overlooked area of the process. Using case studies completed at both small and large-scale mining operations, this technical paper proposes a practical methodology for pattern expansion studies, taking into account terrain parameters, rock quality and explosive strength. This technical paper will use a series of tools geared towards an economical continuous improvement procedure, using UAV particle size analysis to optimize blasting based on “generalized reduced gradient” for non-linear problems, with cost savings being the main objective. For the validation of this methodology, one scenario was created based on the operation’s budget: an economical continuous improvement plan that relied on manual data collection methods in order to baseline and optimize procedures.

Jan 1, 2018

By Bill Birch, Toby White, Ian Brown

costs/benefits of electronic detonators and measure their effects on primary crusher productivity. 9 blasts (3 shock tube blasts, 6 electronic blasts). Measured electricity consumption & primary crusher throughput. Change to Electronic Detonators resulted in a 7% reduction in primary electricity costs and a 15% increase in primary crusher productivity.

Feb 1, 2020

By Mark S. Rayson, Jessy Lee, David O. Johnson, Matthew R. Rawls

The ability to manipulate the structure of liquid chemicals in an explosive is important in mining applications, where precision blasting is crucial for the safe, reliable, economical and eco-friendly extraction of ores. Static mixers allow explosives, emulsion-based in particular, to be custom-made as they offer precise and reproducible mixing without the need for moving mechanical parts. In this paper, we perform numerical simulations on the laminar mixing of two nitrate-based fluids in a Kenics static mixer unit for various mixer parameters. Two numerical methods were investigated in the study of the mixing pattern: solving the mass transfer equation and using particle tracking. The former introduces artificial numerical diffusion which can lead to spurious smearing of the component boundaries, a problem that can be avoided with the latter technique. We have also demonstrated that the particle tracing method is capable of qualitatively predicting the blending patterns under the conditions studied.

Jan 1, 2014

By Rodney Pinksen, Remi Proulx

The IOC Mining and Operations Departments expressed an interest in reducing the amount of oversize material (>1.0 m x 1.0 m x 1.0 m; 39 inches x 39 inches x 39 inches) being produced and its subsequent downstream effects including in-pit sorting and reduction, damage to mobile equipment, and significant delays in the loading pockets and the primary crushers. To achieve this goal an oversize reduction project was undertaken by the mine and to date has significantly improved upon baseline measures.

Jan 1, 2011

By Ruilin Yang

Based on large amounts of field data, this paper evaluates the validity of the above equations. During the evaluation, the different selections of the frequency in the equations were examined with field data. It is found that when they are used to estimate the vector sum values the above equations could result in large deviations from the values obtained directly from the field measurements or the waveform integration. The simple equations may be used to make rough estimations for single components of blast vibration provided that appropriate safety factors are taken into account. For single component vibration, the principal frequency (from ‘zero-crossing’) seems more effective to describe the blast vibration than the dominant frequency (fron FFT) for vibration peak value estimation using the simple equations.

Jan 1, 2012

By Ian Bell, Shahram Tafazoli, Bahram Sameti, Aylin Azmin, Edmond Chow, Nima Ziraknejad

Image-based rock fragmentation analysis methods have been applied by blast engineers to estimate rock size distribution for over 25 years. These methods utilize a wide range of image segmentation techniques, from manual to fully-automated, to delineate the edges of the rocks in the image. In most commercially available image-based rock fragmentation analysis systems, rock delineation results are converted to physical rock sizes by introducing one or more reference objects (e.g., basketballs or other objects with known geometry) to the scene as size-scaling references.

Jan 1, 2014

By Dan McCutchen, Oettmeier

Kelly bar drilling and blasting is unique to Florida, the' Bahamas and other marine limestone areas in the world where blast holes are required but will not remain open for the loading of explosives. This type of rock formation usually yields 1.5 tons of recoverable rock compared to 2.2 tons per cubic yard for competent limestone. The loss of .7 tons per cubic yard is due to voids and sand in the formation. These deposits all contain water to the top of the blast holes which are collared only a few ft. above the ground water level. The working pit is a water filled lake which is excavated from the bank by draglines. These drills have been used in Florida for many years to depths of 65 ft or less.

Jan 1, 1991

By Ali Kahriman, D. Adiguzel, R. Ulger, U. Akkaya

The environmental problems arising from ground vibration has been faced and discussed frequently in various industries such as quarry, mining, civil works, shaft, tunneling, pipe line and dam construction etc. where the blasting operations are unavoidable. This paper presents the results of ground vibration analysis induced by blasting during the construction of the Istanbul Kadiköy-Kartal metro tunnel. Different rock formations in this tunnel route which is 21.6 km in length were encountered during the excavation process by blasting. As a first stage, Hoek’s Geological Strength Index (GSI) values of rock units were determined by using inverse distance weighting method. The GSI values which were obtained from boring data were used when evaluate the data. GSI values were estimated by inverse distance method (figure 3) along with the tunnel route. Afterwards, ground vibration parameters induced by 21 shots which were made in different locations was monitored and passing routes of vibration waves determined. Weighted averages of GSI values were calculated according to distance of the regions where vibration waves passed. Multi regression analyze were made with using frequency, charge per delay, GSI and the distance between the shot point and monitor station. The main goal of this study is to investigate the relationship between ground vibration frequency induced by blasting and GSI.

Jan 1, 2011

By Xue Yongpeng, Zhu Zhenhai, Zhu Ming

The purpose of the Solid Medium Controlled Blasting Technique and Its Applications is to have the inside of the vessel-shaped framework (e.g: oil tank , water pool, gas chamber, chimney, water tower, grain warehouse and etc.) or the one side of the thin wall-shaped structure(e.g: steel bar concrete wall and etc.), both of which are intended to be demolished, inserted with the required solid medium (e.g: soil , sand , coal, salt and etc.) ,in which there is a certain mass density, and then through which the blasting energy is transferred to fulfill the blasting task. For such a technique, it is necessary to bury the explosives into the inserted solid medium and then to start the explosion to blast the intended target into pieces. The filling of the solid medium may be done mechanically or by man. Compared with the water pressure blasting technique, this one has the characteristics of good effect. wide application, simplified construction procedure , safe and reliable operation and small vibration (less vibration than water pressure blasting by 80% to 90%)in particular without any flying stones, thus resulting in better and comprehensive social and economickfficiency.

Jan 1, 2000

By Derek Morris, Vito Saccheri

In the monitoring of seismic exploration (whether by explosive or vibratory energy sources), the intensity of shaking at neighboring structures can now be measured quite accurately and comprehensively with portable equipment. However, the interpretation of the results is open to considerable debate and mis-interpretation. One conventional approach is simply to compare the maximum measured peak particle velocity (PPV) with a permissible standard – usually 0.5 inches/sec (1.3 cm/sec) because this is the value generally referred to in the U.S. Bureau of Mines standard. This can be very conservative, both for surface structures, and especially for buried structures like pipes, for which absolute reliance on PPV obscures the true complexity of field problems. Quite apart from the fact that the full Bureau of Mines standard is actually a reasonably complex function of frequency (for the simple reason that in differing parts of the frequency spectrum, damage may be displacement or acceleration controlled), the effects of spatial direction and orientation are often ignored.

Jan 1, 2009

By James C. Irvine

Meramec Mining Company's Pea Ridge underground mine is presently involved in a large scale pillar recovery program and has made use of both rotary and down-the-hole drills for large diameter blastholes. Groups of pillars have been blasted with water gels in massive blasts which have broken in excess of one million tons of ore per blast. An outgrowth of the pillar recovery program is the combination of rotary and down-the-hole drills to develop vertical "raises" between mine levels. This paper outlines the Pea Ridge procedure for pillar blasting including the use of non-electric caps. Techniques and loading rates are discussed, and safeguards against blasting damage which were developed as a result of the program are presented.

Jan 1, 1976

By Anne Caroline Costacurta Polli, Jose Rojas Cáceres, Roberto Mahler de Morais, Thais Costa Silva

The technology and the knowledge about the behavior of explosives and detonation accessories allowed to create new products for different situations by the restrictions imposed by the market. In a Brazilian underground copper mine the restriction occurred in the use of high grammage Det Cord in the development heading blasts perimeter holes. Enaex Brazil has developed Densiex UG™ (Low-Density Bulk Emulsion), a water-resistant bulk gassing emulsion with a density ranging from 0.60 to 0.90 g/cm³ to replace the high grammage Det Cord in blasts. That product is pumped in the same Mobile Manufacturing Unit (MMU) as Enaex Brazil's standard underground (UG) bulk emulsion. This product has a Lower Velocity of Detonation (VOD), vibration, and detonation pressure, which contributes to a better finishing of the drift, lower impact in the support structures, and lower generation on unstable rocks in the perimeter of the drift. This case aims to summarize the results of the work on the application of the Low-Density Bulk Emulsion in perimeter holes in an underground development gallery at an underground copper mine in Brazil. During this work, 10 horizontal drift blasts were performed using the Low-Density Bulk Emulsion, which presented an average density of 0.64 g/cm³, increasing safety, a 25% reduction in overbreak, a 23% reduction in scaling time, elimination of rework, and a saving of $135,000 per year for this business partner that immediately implemented this new product in all blasts at this mine.

Jan 21, 2025

By Ray Slavin, Remi Proulx

The Meikle Mine is a mature underground gold mine utilizing primary and secondary longhole open stoping method with delayed backfill. Combined production with the newly developed Rodeo Mine is 4700 tons per day (4265 tonnes per day) of ore. The vast majority of Meikle Mine production comes from secondary and remnant stope blocks. Remnant stopes are ore blocks that were left behind in the initial mining sequence due to various reasons. Mining of these remnant blocks has created many challenging blasting situations. The application of electronic initiation to blast remnant stopes has proven extremely beneficial. Electronic initiation has provided the blasting engineer with a high degree of flexibility with respect to timing to successfully extract these difficult stopes. Post blast assessment of the remnant stopes using the mine’s cavity monitoring system (CMS) demonstrates that the mine is maximizing ore recovery and minimizing waste dilution. The largest remnant stope blast to date required 54 holes and produced 6700 tons (6075 tonnes) of ore. Another area where the application of electronic detonators has proved successful is in the extraction of slots in which ground conditions are extremely poor. Taking the slot blasts in one shot with double-decked holes as opposed to two single-decked shots has eliminated the need to clean and or re-drill holes. The ability to open the slots in one blast has helped reduce the total mining cost. This concept has recently been expanded to blast complete stopes in one shot. This reduces the stope cycle time considerably and allows the mine to bring ore forward. Current plans for 2004 are to excavate 50% of mine wide stope production using electronic initiation technology.

Jan 1, 2004

By Y Wada, Y Ogata, T Nishida

"Shaped charge is used for blast demolition of steel construction in general. It is important tocontrol movement of cutting part with shaped charge for the blast demolition of steel construction.Movement of cutting part was studied in the small scale experiment with steel bar. A numericalsimulation using the Discontinuous Deformation Analysis (DDA) was carried out. The DDAmethod was applied to the full scale blast demolition of steel construction. Results of thesenumerical simulation was compared with the blasting demolition work of steel tower."

Jan 1, 1999

By Tyler Rockley, Cara Rosen

Blasting at a granite quarry in eastern Maryland produces elevated air blast readings that can fall into the cautionary zone for the state of Maryland environmental regulations on a semi-regular basis. When designing blast patterns in this quarry, challenging geology creates rough and uneven blast faces that can be difficult to capture with 2D laser profiling fully. Utilizing several methods known to manage high air blast results like pattern adjustments, decking, and timing changes have not achieved consistent outcomes. Accurately capturing and modeling this geology is the key to controlling high air blast. 3D modeling and profiling by drone is the solution to understanding accurate face profiles and real minimum burdens. Using 18 months of blasting data and air blast results to establish a baseline, the comparisons between blasts designed with 2D profiling and blasts designed with drone 3D profiling show improvement in air blast levels. Additionally, shots with completed drilling were drone profiled to understand precise amounts of burden for each borehole. This 'audit' of a blast allows for custom loading of explosives, accommodating the amount of burden present on the blast face. 3Dprofiling is not a new tool in the blasting industry, but a drone alleviates some of the restrictions ground systems face. Controlling and managing air blast, as it pertains to face burdens, requires an understanding of those burdens from all angles. A drone provides that distinct level of insight. The results of this study indicate that drone profiling is managing the customer's air blast readings, allowing the customer to maintain their license to operate within the community.

By L. A. Heim, E. A. McCullough, N. J. Amiotte

The explosives industry is subject to the laws of multiple jurisdictions, which means that several regulatory agencies are responsible for governing different aspects of the commercial explosives industry. Among these regulators are the Mine Safety and Health Administration (MSHA) who implements codes that better ensure both occupational and public safety which is influenced by professional blasting projects and the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF), who enforces commercial explosives storage and security, among other responsibilities.

Jan 1, 2014

By 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 quarry blasting. The natural limestone bedrock in occurs at or near the surface in southeastern peninsular Florida. While the shallow overburden soils is advantageous for mining purposes, vibrations from blasting has been a contentious issue in South Florida due to the proximity of the mines to several residential communities. White Rock Quarries and Krome Quarries are two active mining facilities in South Florida which generate numerous complaints, insurance claims, and lawsuits from residents in nearby communities who claim that the vibrations cause damage to their houses. Both quarries are located on the eastern edge of the Everglades, with thousands of nearby residences at the western edge of development in Broward and Miami-Dade Counties. Data obtained from over 400 publicly available blast monitoring and associated seismograph reports from White Rock Quarries were reviewed and compiled. The data was used to emperically develop a conservative estimate of the ground attenuation rate based on the scaled distance from the blast origin, which can be compared to Figure B-1 from USBM RI 8507 to determine whether it is feasible if damage could have occurred at a given property.