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By Sarma Kanchibotla

In mineral industry operations the insitu ore is’separated from the waste rock and is subjected to a series ofprocesses to convert it into a valuable product. Profitability of any operation in this industry depends on how eficiently the insitu rock (ore -I- waste) is converted in to the final product and how much value @ice) it commands in the market. Traditionally, the total process in mineral industry is classt@ed into two groups as mining and milling, and optimised independently without considering the impact of one over the other. This paper investigates the impact of mining operations (especially blasting;) on downstream processes and demonstrates the potential benefits of the “Mine - Mill Blasting” approach through simulations and case histories.

Jan 1, 2000

By Carlos Agreda

"It is widely accepted that the rock blasting results are a function of several stochastic variables given by: -The natural geological structure of the rock mass (joint spacings, discontinuities length orientation and characteristics, physical-mechanical properties, such as: ultimate strengths and elastic properties, etc.).-The detonation and explosion parameters of the explosive mixture (V.O.D., P2, T2, Q3, etc.).-The drilling and blasting pattern dimensions.-In this paper the most important stochastic variables regarding with the rock mass and the blast design dimensions before mentioned are identified, described and discussed.A non linear programming method to calculate the optimum burden Bo) is proposed and discussed.The great impact of the stochastic variable called burden (B) on the rock blasting results is emphasized. A comparison between burden theoretical calculations and some field blast results is also shown."

Jan 1, 1996

By Brian W. Stump

The cessation of testing of any nuclear explosive devices in all environments is the goal of the Comprehensive Test Ban Treaty. In order to assure compliance with such a treaty, an international monitoring system has been proposed. This system will include seismic, infrasound, hydroacoustic and radionucleide monitors located throughout the world. The goal of this system is the detection of any nuclear test. In preparation for this treaty, a series of monitoring system tests, focusing primarily on seismic observations, have been undertaken. The most recent of these tests, Group of Scientific Experts Technical Test Three (GSETT-3), provides valuable data for assessing future monitoring systems. During the course of this experiment, seismic events associated with earthquakes, nuclear explosions and mining explosions have been recorded. This presentation will discuss the numbers and types of mining explosions triggering the system, in a particular area. Possible implications for the mining industry will be explored.

Jan 1, 1997

By TA Louw, Dr CM Lownds

In an era where profits are constantly being eroded, mines are looking towards technology developments to assist them in solving mining problems and reducing mining costs. An emerging technology that could assist mines in becoming more cost effective is electronic detonators. Electronic detonators have been under development for several years. Over the past three years, the spotlight has fallen on commercial use of electronic detonators and the extent to which the promise of precise and programmable timing can assist mines with their environmental and productivity problems. This paper uses case studies to demonstrate both surface and underground applications where electronic detonators and blasting systems were used to solve typical mining problems such as vibration and fragmentation. Safety aspects such as hanging wall conditions and high wall stability also benefited from the use of electronic detonators. The paper also demonstrates how the use of accurate electronic detonators and blasting systems has resulted in improved/more even fragmentation with further downstream efficiencies. These efficiencies may include increased cast percentages, reduced oversized rocks, quicker cleaning times and increased production rates.

Jan 1, 2004

By Roger Keller, Jason Ryan

A number of studies have evaluated excavation methods for the construction of subsurface facilities for a potential deep geologic repository for the disposal of nuclear waste at Yucca Mountain, NV. Many of these studies suggest that where TBM (tunnel boring machine) methods are not applicable and alternative mechanical excavation methods can not efficiently excavate harder rock drill and blast methods may be the most efficient means of excavation. However, a number of concerns regarding drill and blast applications have been raised in these evaluations, most notably the affects of blasting on the surrounding perimeter, as isolation of the waste by the natural barrier of the surrounding rock is a key element in the concept of a deep geologic repository.

Jan 1, 2001

By Rolly Thorpe

Bulk emulsion explosives have been used at surface mines and quarries for many years. Recently, this technology has been adapted for underground use in relatively confined work areas and in smaller diameter blastholes.

Jan 1, 1994

Jan 1, 2002

By J Lyall Workman

This paper examines the comparative economics of cast blasting to alternative stripping techniques. There are several scenarios where a mine may consider introducing cast blasting. However, there are other alternatives such as adding dragline capacity or introducing a prestripping operation. The question becomes which alternative will be more economical.

Jan 1, 1998

By Barbara A. Sciever, John H. Sr Schue

Riverboat gambling has caused quite a sensation among people since its talk of coming to Illinois. The year 1992 marked the start of an era for people that had a penchant for gambling, it was the year that riverboat gambling was legalized in the State of Illinois.

Jan 1, 1995

Tracer blasting is commonly used in Canadian underground mines for overbreak control. It involves tracing a column of ANFO with a low strength detonating cord. In order to investigate the effectiveness of tracer blasting in perimeter control and to understand its mechanism, a field experimentation was conducted which involved drifting, benching and pipe tests.

Jan 1, 1994

By J P. Tidman

The problem of blasting fragmentation has received a good deal of attention in recent years. Progress by the scientific method requires a good set of experimental data as a benchmark to test models. Recent models have become so complex that it is not possible to use the results of field data because the complete set of parameters needed to describe the rock and/or explosive are not available.

Jan 1, 1991

By Ronald L. Sanders

The prevailing view of the coal mining industry by government officials is: "Tell everyone you're coming - Don't let anyone know you're there - And remove all evidence you have ever been there". Now the irony is that the government inspectors are just enforcing the law. The coal mine operators seem more interested in genuine reclamation than the inspectors.

Jan 1, 1979

By Fumihiko Sumiya, Koichi Kurokawa, Yukio Kato, Tetsuya Sawada

In some metal mines, it is a serious problem the decomposition of explosives which occurs suddenly by contact with ore containing pyrites under high temperature conditions. In the present paper, we investigated heat resistant properties of emulsion explosives and other industrial explosives by contact with ore containing pyrites under high temperature conditions.

Jan 1, 1992

By Mark S. Stagg, Stephen A. Rholl

As part of its research program to evaluate efficient design criteria for improved blast fragmentation, the Bureau of Mines has developed two computer programs to facilitate data analysis. Results of these two programs are used to better understand the fundamental parameters of blasting for surface mine rock fragmentation.

Jan 1, 1990

By Anne Charline Sauvage

Blast designers and blasters need to know the rock mass influence on blast to increase explosive effi-ciency and to optimize costs, but also to succeed in limiting blast emissions (vibration, overpressure, flyrock) This paper presents an applied approach which makes it possible to structure the information con-cerning the rock mass and the blasting.

Jan 1, 2013

By Unknown

ATF has provided a Guide to Recording Suspicious Persons Description in the Safety & Security Brochure. This guide may be useful for recording descriptive information on any suspicious individual. Suspicious activities can be reported to ATF’s 24-hour hotline listed in the front of the Guide or to your local law enforcement authority.

Jan 1, 2009

By Qingshou Chen, Gongbo Li, Hengqian Ran

A method for safe fracture of rock, concrete and other brittle solid material using dynamic water pressure by explosion is provided. The propagation of the pressure is studied with Allievi water hammer theory. Wave equation and velocity formulas of the pressure propagation are shown. The dynamic water pressure is tested in the lab. The propagation of the pressure is simulated by MMIC-2D. The results of fracturing rock in the lab and on a quarry are presented.

Jan 1, 2000

By David A. Smith, B L. Jr Lindsey

Arkansas bauxite varies enormously in its consistency and composition which makes blasting a very difficult operation. Blasting rounds have to be designed based on each particular mine's ore characteristics. The variances are so great in some mines that blasting procedures have to be changed almost daily.

Jan 1, 1979

By T Michael LeBlanc

Drill trajectory deviation is a recurring problem in vertical retreat stoping operations. As a result of this deviation, 60 kilogram (165 millimetre diameter) and 103 kilogram (302 millimetre diameter) explosive charges are routinely detonated beyond ore/waste contact zones. Consequently, there follows a reduction in finished stope wall stability and an increase in ore dilution.

Jan 1, 1996

By Michael E. Curtis

This paper outlines a study performed to analyze the advantages of utilizing a blasting agent with a velocity of detonation that is 1.3 to 1.4 times the P-wave velocity of sedimentary shales and sandstones at a major Midwest coal operation.

Jan 1, 1997