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By Rob Farnfield, Ben Williams, Bob Woolley

This paper outlines how drilling safety standards are being driven forward in the United Kingdom’s surface mining and quarrying industry with developments in equipment, procedures and competence.

Jan 1, 2010

By Fumihiko Sumiya, Yukio Kato, Yoshikazu Hirosaki

Secluential blasting is one of the most popular methods in blasting. tiowever, it is well known that an emulsion explosive can be dead-pressed by dynamic pressure generated by the previous detonation. It is difficult to gain the expected blasting performance due to tb.e malfunction of explosive caused by deadpressing and shock desensitization. Such malfunction of an explosive is undesirable for safety blasting operation. Voids in the emulsion explosives will considerably affect the performance of explosives such as sensitivity, detonation velocity (DV), pressure-resistance and so on. To clarify the detonability and the performance of precompressed emulsion explosives, the DV was measured. Three types of microballoon or micro bubble ; two types of glass microballoon(GMB), resin microballoon@MB) and chemical gas bubble ; were used as sensitizers for the sample emulsion expiosives. The underwater explosion test was carried out to load dynamic pressure into the sample explosives. The dynamic pressure was generated by the detonation of a donor explosive, and the DV of the sample explosives as acceptor was measured by ionized gap terminals. The dynamic pressure level and initiation interval for the donor and the acceptor were chosen as experimental factors. The detonability was carefully investigated at short initiation intervals taking into consideration the interaction between same delays caused by the deviation of the ignition time of the electric detonators. From these experiments, the following results were obtained ; A) The DV of precompressed emulsion explosives was low compared with that of uncompressed emulsion explosives in all pressure conditions. B) The decrease of DV in the sample explosives sensitized by GMB s was larger than that of DV in the sample explosives sensitized by RMBs or chemical gas bubbles. C) The recovery of the detonability occurred rapidly in the sample explosives sensitized by RMBs and chemical gas bubbles. However, a long period was needed for the recovery of detonability in the sample explosives sensitized by GME! s. It was concluded that the type of microballoon and micro bubble significantly influenced the detonability of precompressed emulsion explosives.

Jan 1, 2002

By Christodoulos Xiouris, Ali Reza, James Karnesky

A rocket parachute signal flare is often used to signal a maritime emergency. In the general operation of these devices, a solid rocket motor propels a metal body to an altitude of approximately 1000 ft (305 m). At the end of the rocket motor, a propelling charge drives a signal flare and parachute out of the metal body and ignites the flare, which then burns for approximately 40 seconds as it falls to earth. In this paper, we describe an engineering investigation of an accidental ignition of a rocket parachute signal flare, which caused injury to the user. T

Feb 1, 2020

By Bonifacio Digay

Stawell Gold Mines (SGM) is an underground mining operation located in Victoria, Australia.The mining method employed is long hole retreat stoping, utilising up and downholes and artificial concrete pillars. Stawell is currently mining the Golden Gift and Magdala orebodies.

Jan 1, 2012

By Grant Small, Deon Pieterse

Reactive ground conditions at an open pit manganese mine in the Northern Cape of South Africa resulted in an unexpected detonation.

Feb 1, 2020

By R R. Dimock

A goal of all mine operators is to optimize the breakage of the inplace rock to achieve maximum excavating efficiency. The use of the seismograph at Kennecott Copper Corporation's Nevada Mines Division, open pit mine in Ely, Nevada, has demonstrated that optimum blastability can be predicted by knowing the seismic velocity of the inplace rock. The relationship of seismic velocity to the quantity of the explosive required to achieve adequate breakage of the material can be determined. Once quantified, this relationship can be used by the mine operator to obtain the optimum drill pattern and powder factor for breaking the material to be excavated. A substantial savings in primary and secondary drilling and blasting costs can result from using the seismograph for blastability determination.

Jan 1, 1976

By Michael S. Wieland

Toxic fume concentrations from industrial mining explosives depend somewhat upon the type of rock (or other strata) confinement. Though traditional detonation theory disregards this influence, the work principal from thermodynamics reveals it, when the violent interactions that transpire within the rock blast are taken into proper account. Resolution of the work principle technique requires total thermodynamic equilibrium under constraint, so the nonequilibrium dynamics is rendered in that way, using an old trick from theoretical mechanics that revises the representation of forces. The rock pressure reduces to a four-component sum: the rock compressive strength and natural atmospheric pressure, as reckoned quasi-statically, and the gravitational influence and reversed inertial resistance, as reckoned dynamically. Tabulated specie concentrations and graphical trends reveal the dependency upon rock pressure, rock temperature and the fuel-oil percentage in ammonium nitrate mixtures (ANFO), used to illustrate the model. Rigid-wall test chambers have notable ullage (residual space), where rapid expansion influences the reaction quenching, yielding a fume spectrum unlike that for rock confinement; reported rock tests are therefore used for comparisons. For the thermodynamic regime where quenching occurs, seven concentrations are resolved, including carbon monoxide (CO) and total nitrogen oxides (NOX). Their trends yield inferences regarding the way unwanted charge desensitization from transitory hole-to-hole wave impact in conjunction with reduced rock pressure can yield nasty toxic fumes, the dark rusty cloud phenomenon!

Jan 1, 2005

By Alexander S. Escalante, Luis R. Ramirez, Nelson A. Arostegui

Research, analyze, discuss, design, and build an electric oven to perform one of the quality control tests the fanel or common fulminers to determine what temperatures they can detonate at. Give practical applications, conclusions, recommendations and bibliography.

Feb 1, 2020

By Christodoulos Xiouris, Ali Reza, James Karnesky

A rocket parachute signal flare is often used to signal a maritime emergency. In the general operation of these devices, a solid rocket motor propels a metal body to an altitude of approximately 1000 ft(305m).At the end of the rocket motor, a propelling charge drives a signal flare and parachute out of the metal body and ignites the flare, which then burns for approximately 40 seconds as it falls to earth. In this paper, we describe an engineering investigation of an accidental ignition of a rocket parachute signal flare, which caused injury to the user. The components of the flare involved in the accident were inspected via x-ray and microscopic imaging techniques, and compared with those of unfired flares recovered from the same vessel. Chemical analysis of residue on recovered components from the accident flare was also performed. These comparisons were used to determine the likelihood that the actuation mechanism had been deliberately manipulated. In the subject model of the flare, ignition of the rocket motor is accomplished through a percussion cap which is struck by a firing pin. Prior to activation, the firing pin holds down a pre-compressed spring. We present a comparison of the ignition system of the incident flare with those of other rocket parachute flares, which do not incorporate any stored mechanical energy.

By Charles Clark, Mark Mukhija, Jaime Klein

Comminution – the reduction in size of solid materials – is the most energy intensive component of the mining process (Bauer, 2015). It is estimated that comminution consumes around three percent of all electricity generated in the world (Ceecthefuture.org, 2017). On an energy equivalent basis, downstream processing consumes six times more energy than drilling and blasting (Kanchibotla, Sarma et al., 2014).

Jan 1, 2018

By Robert Hopler

CHAPTER I. DEFINITIONS AND CLASSIFICATIONS. Definition of Explosives. SECTION 1. The term “Explosive” or “Explosives” whenever used in this ordinance, shall be held to mean and include any chemical compound or mechanical mixture that contains any oxidizing and combustible units, or other ingredients, in such proportions, quantities or packing that an ignition by fire, by friction, by concussion, by percussion or by detonator of any part of the compound or mixture may cause such a sudden generation of highly heated gases that the resultant gaseous pressures are capable of producing destructive effects on contiguous objects or of destroying life or limb, and includes all the articles specifically mentioned in Section 3 herein, and all other similar articles

Jan 1, 2013

By Peter Duniam, Vivian Patz

History of the ExEx 1000 CAB system. l What we’ve learned using electronic timing. l Requirements for a second generation. EDD system. l The ExEx 2000 system - simple, versatile and cost effective

Jan 1, 1997

By Omer Yilmaz Erkoc, Gulsec Uyar Aldas

Blasting techniques, which have been used for a long time in Turkey, are powerful and economical tool in producing raw material in mining, quarrying, construction .etc. industries. The development of the society within the world has resulted in a substantial increase in the scale of such industrial projects. However, the expansion of such activity has been matched by an increased public awareness of environmental issues, particularly when it occurs in relatively close proximity to residential areas. One of the most troublesome issues facing the mining, quarrying and construction industries when carrying out their blasting activities is that of ground vibration. Because, blasting induced ground vibration can reach to very far distances from the source and has the potential for damage to concern to the inhabitants of property.

Jan 1, 2002

By John Brennan

Necessity, they say, is the mother of invention. Certainly that sentiment held true during the early stages of explosive engineering. While seaside forts were concerned over static ignition of their black powder caches in the 14th century1, the mining industry in the 1800s were plagued by accidents surrounding the ignition methods for their black powder blasts.

Jan 1, 2011

By David Flores, Benjamin Cebrian

This paper describes extensive engineering approaches to achieve both dilution control while not hurting fragmentation in the very hard, massive ore sections of a mine case study. Ore Tracker microchips are used to correlate performance of these designs at the SAG mill (bottleneck of this specific operation). Another gold mine uses the same technology to detect when and where operational dilution is happening. The system tells where flagging of the different ore bodies has been followed in order to detect which operators pass the excavation limits beyond ore control flagging.

Feb 1, 2020

By Riaan Van Wyk, Gys Landman

In today’s mining environment the use of radio communications in the form of two-way radios, cellular phones and even automated mining, form a vital part of the daily operations of a mining site. The radio transmissions that are used are a form of energy and as with all other types of energy it can have an influence on blasting equipment.

Jan 1, 2011

By Michael M. Jackson

"The mining industry has for some time compared explosive energy requirements to theresults obtained using ANFO. Drill patterns, powder factors, and explosive bulk strengthshave all been developed based on the detonation characteristics and blasting resultsexhibited by ANFO. However, there are some mining applications where the use of ANFOcan cause over_blasting if loaded to acceptable collar heights or surface breakage problemsif collar heights are reduced. A specialized, low strength, low density water gel explosivehas been developed that has loading densities in the range of 0.4 to 0.7 g/cc. The uniquecharacteristics of the low density water gel explosive is that the explosive can beformulated with a range of available bulk strengths while maintaining excellent detonationsensitivity for use in applications involving ore/waste control, restricted blast patterns,small bench heights, etc. The"

Jan 1, 1993

By B. M. P. Pingua, M. Nabiullah

Number of mine accidents occurred in Indian surface mines are due to poor quality of explosives and blasting accessories. Amlori open cast project is one of the major coal producing projects in India. Standard drilling and blasting parameters are used to achieve desired productivity of the mine. 150 and 260 mm diameter blast holes are used for blasting in coal and overburden benches. Most of shovel benches are 12 to 16 m in height and dragline benches vary from 25 to 30 m. High-energy bulk emulsions are used for blasting. The cup density and velocity of detonation of bulk emulsion explosives are 1100 to 1200 kg/m3 and 3.8 to 4.5 km/s respectively. An incident occurred on fire bench of Amlori open cast mines during mucking of blasted muck.

Jan 1, 2008

By Carl E. Jones

This presentation discusses the properties of the two-component explosive, KinePak, and how it is used by the utility industry.

Jan 1, 1978

By Alan B. Richards, Aleks Todoroski

The undesirable effects of blasting fumes can be controlled by minimising the amount of fume created, and by avoiding the movement of the fume plume to sensitive locations. Substantial progress has been made by the blasting industry to reduce the amount of fume typically created by blasting, but at this time no specific blast can be guaranteed to be ‘fume free’.

Jan 1, 2017