Open pit blasting pdf

Blast pattern the plan view of the drill holes as laid out for blasting. In most of mine works which including open pit production methods use almost same stage in blasting. More than one row of holes can be blasted in the same round. Stepbystep were going to explain what we should do in an open pit bench blasting. Fragmentation of the rock after blasting is an important determinant of the cost associated with these two components of mine development. An open pit bench blasting application mining consultant.

Volume 1 deals with the fundamental concepts involved in the planning and design of open pit mines. New gpsenabled applications have improved strata recognition capabilities that help drill and blast engineers develop more appropriate and more suitable blast designs. Measurement of blast damage office of surface mining. Subjects covered are mine planning, mining revenues and costs, orebody description, geometrical considerations, pit limits, production planning, mineral resources and ore reserves, responsible mining, rock blasting, rotary drilling, shovel loading, haulage trucks and machine availability and.

The water desensitises a proportion of the fuel, upsetting the oxygen balance and resulting in the production of nitrous oxides. The availability and production capability of surface equipment makes open pit mining a very attractive choice. Pdf this chapter will describe drilling plan, blast plan, fragmentation, open pit slope, and safety related to open pit mining. Effective slope design relies on the estimation of rock mass strength. H blasting in surface excavation mining and blasting. The placer granny smith sunrise dam open cut gold mine is located near laverton, wa. Despite the progress, injuries and fatalities continue to occur.

Much of the information in the module is derived from the surface mining control and reclamation act of 1977 smcra. A comparative study of ground and underground vibrations. Sean dessureault surface and underground excavations methods,techniques and equipments. Hustrulid, w, 1999, blasting principles for open pit. To obtain wellfragmented rock by blasting, explosive energy must be well distributed throughout the rock. Prediction of rock fragmentation in open pit mines, using neural network analysis kazem oraee1, bahareh asi2 loading and transport costs constitute up to 50% of the total operational costs in open pit mines. Click download or read online button to get blasting principles for open pit mining book now. Addresses the challenge of optimizing the design of blasts for open pit mines and quarries.

Controlling the adverse effects of blasting this module addresses the control of offsite impacts that result from blasting, namely. Pdf in most of the openpit preciousmetal mines in nevada, there is no clear geological distinction between ore and waste material. Building the appropriate policy means it needs to be process driven, not people driven. Divided into two volumes, this accessible work describes the principles involved in hard rock blasting as applied to open pit mines. In open pit blasting, the number of free faces and the confinement of the last two rows of holes to be fired are factors to be noted, as well as the relative direction of the blast in re lation to the orientation of the major discontinuities or preferential orientation of the joint sets. The firing sequence of a chevron pattern can radically alter the. The aims of this paper are to determine the weaker protection objects by comparatively.

Large surface mines may detonate up to two million pounds of blasting agent in a single shot. Moreover, it has been demonstrated in this study that all over pressure magnitudes are less than 4 db, which is the safe limit of air blast level. Air blast introduction on surface mining, blasting technique may be considered as the most economical method used for fragmenting rocks masses. By definition, bench blasting is blasting in a vertical or subvertical hole or a row of holes. Blasting principles for open pit mining download ebook pdf. Openpit mine planning and design enterprises university of.

The best perimeter blasting results can be achieved in tough massive rocks. Optimized design of drilling and blasting operations in. Blasting, primarily trench and ditch blasting, can displace rock and damage adjacent pavement and underground utilities. By definition, bench blasting is blasting in a vertical or subvertical hole or a row of holes towards a free vertical surface. D blast hole diameter mm, wstandard deviation of the drilling accuracy m, ltotal charge length m, hbench height m. Prediction of rock fragmentation in open pit mines, using neural. History of explosives and blasting mining engineer first. Technologies for optimizing drilling and blasting in openpit. Unesco eolss sample chapters civil engineering vol. Noxious fumes blasting generates carbon monoxide and other noxious fumes. Pdf several theories have been developed by various authors for estimating open pit blast design parameters such as burden, blasthole. For maximum profitability the development of the pit requires strict wall control blasting techniques to.

Batu hijau is budgeted to produce 140 million pounds of. Electronic detonators vs non electronic detonators and new. Improving double bench face performance at the ekati diamond. The firing pattern has to be designed so that each blasthole has free breakage. Bmt works with geologists from over 105 open pit operations around the world to accurately measure 3d blast movement so that the ore is sent to the mill and waste ends up in the waste pile. Ground vibrations originating from bench blasting may cause damage to slopes, structures, and underground workings in close proximity to an operating open pit mine. In open pit mines the required explosive displaces ore boundaries from where the geologists originally defined them. In order to implement an adaptive blast design strategy for open pit mines, two problems must first be solved. Dangers of toxic fumes from blasting centers for disease. If the blasting agent is diluted by mixing with drill cuttings at the top or bottom of the borehole it may not detonate properly and excessive quantities of toxic fumes may be produced sapko, 2002.

Blasting principles for open pit mining download ebook. As a rule, openpit and coal strip mines using large drills will drill presplit holes that range from 9 to 12. In both surface and underground mining operations there is a need for the use of special blasting. The panda pit is centered on a diamondiferous kimberlite pipe.

Mechanism of rock breakage while release of explosives energy upon detonation and other relevant points are discussed below. In normal blasting all holes do not blast at the same time. Chevron blast pattern firing patterns in normal blasting all holes do not blast at the same time. Drilling and blasting for stable pit walls mine water risk in slope stability monitoring and maintaining open pit slopes assessing the risks with open pit mining learning outcomes after successful completion of the course, you will have a better understanding of the open pit mine planning process. Surface blasting safety procedures blasting materials surface delays, detonators or blasting caps, boosters, safety fuse, downline and other explosives used for blasting.

Kemeny university of arizona, tucson, arizona, usa j. When an explosive charge is detonated, chemical reaction occur which, very rapidly changes the solid or liquid explosive mass. By definition, bench blasting is blasting in a vertical or subvertical hole or a row of holes towar ds a free. A open pit stripping the overburden is always a problem. Drilling and blasting are the two most significant operations in open pit mines that play a crucial role in downstream stages. Blast design figure 82 staggered pattern figure 83 sing figure 81 square or rectangular pattern. During a construction blasting operation near marlboro, ny, flyrock was showered on passing motorists on route 9 w about 180 feet from the blast pit. Bench blasting is a common blast technique most often used for open pit mines. The fumes generated during blasting operations, especially during trenching operations, can migrate and collect. Blasting operations are used as mining technology here so the rock waste dump could be influenced by these vibrations significantly. Case study combined production and trim blasting pt newmont nusa tenggara, batu hijau, indonesia. Subjects covered are mine planning, mining revenues and costs, orebody description, geometrical considerations, pit limits, production planning, mineral resources and ore reserves, responsible mining, rock blasting, rotary drilling, shovel loading, haulage trucks and machine. Vibration response of waste rock dump in open pit mine caused by blasting operation 72 only the mined out part of the quarry was at the disposal of waste rock deposit. In openpit blasting, the number of free faces and the confinement of the last two rows of holes to be fired are factors to be noted, as well as the relative direction of the blast in re lation to the orientation of the major discontinuities or preferential orientation of the joint sets.

The first volume introduces basic engineering concepts and the building blocks that make up a. In the open pit mine near jarnoltowek poland, phyllite is excavated, and rock waste is deposited on the dump directly in the mine. Ptnnt operates the batu hijau coppergold open pit mine, located in the west nusa tenggara province of indonesia. International symposium on stability of rock slopes in open pit mining and civil engineering. Case study combined production and trim blasting pt newmont nusa. Blasting principles for open pit mining, set of 2 volumes. Bench blasting is normally carried out as short delay blasting. The evaluation method is generally ordinary kriging with mining block sizes ranging from 10 x 10m to 100 x 100m to 250 x 250m in the plan view. National institute of technology rourkela this is to certify that the thesis entitled optimization of blasting parameters in opencast mines submitted by sri manmit rout roll. Evidently, even rise in cost of wall control blasting at higher quality and adequate control results in increased safety of mining, stability of pit walls and, consequently, in higher economic efficiency of open pit mining in whole. The composition of explosives is balanced chemically to produce the desired effects in blasting. It is important to monitor and predict ground vibration levels induced by blasting and to take measures to reduce their hazardous effects. The bounds of the blast area were not adequately determined for this blast.

In an open pit mine slope, rock mass has multiple joint structures and blasting operations have an obvious influence on its stability. Cunningham 1987 notes that the uniformity coefficient n usually varies between 0. While previous research has focused on optimizing these operations as two separate parts or merely in a specific parameter, this paper proposes a system dynamic model sdm for drilling and blasting operations as an interactive system. Use of tungsten carbide bits began in mining in sweden.

Optimization of drilling and blasting operations in an open pit mine. Optimization of blasting parameters in opencast mines. Technologies for optimizing drilling and blasting in open. The drilling process is used in quarries, open pit and underground mines for blasting operations which are conducted to fragment the. Geotechnical considerations in open pit mines version 1. Blast plans are mandatory to ensure that blasts can be. The first volume introduces basic engineering concepts and the building blocks that make up a blast design. Fragmentation of the rock after blasting is an important. Mcintyre and hagan 1976 report vertical cracks parallel to and up to 55 m behind newly created open pit mine faces where large multirow blasts have been used. Reduce ore dilution and loss in open pit mines bmt.

This article references the panda pit, which was the first open pit diamond producer in canada. Mechanism of rock breakage while release of explosives energy upon detonation and other relevant. The objectives and mechanics of control blasting are discussed. Failure to accurately account for blast movement results in ore loss, dilution, or misclassification low grade to high grade ore, sulfide to oxide, or other contaminates. Hi everyone, i want to show an application from beginning to end in open pit bench blasting. A large number of examples illustrate the application of the principles. Presplit blasting spacing hole diameter x 12 burden 0. The second volume goes into more depth to provide a better. Pdf application of blast damage when modelling open pit. Ground vibrations and air blast effects induced by blasting in open pit mines.

For example, elimination of earth slide is connected with. Okubo encyclopedia of life support systems eolss figure 2. This site is like a library, use search box in the widget to get ebook that you want. Shotplu the situation previous blasting practices at batu hijau required sequential firing of production and trim shots to facilitate free face firing for all trim shots to minimize damage to pit walls. The dump had four levels at the time of performed seismological measurement fig. Benches may be designed and carried forth with more. Optimized design of drilling and blasting operations in open. It is currently an open pit operation located approximately 300km northeast of yellowknife in the northwest territories in canada figure 1. We operate open pit mines worldwide, providing high quality solutions and contributing to its optimization and efficiency thanks to our unique technologies and team of experts, we can be involved from the design and planning of the blasting, to its execution and the measurement of results, always ensuring that we exceed the expectations of each. Significant progress has been made in the reduction of serious injuries and fatalities resulting from mine blasting operations. Change in production and productivity of us coal mines the higher productivity for open pit mining equipment also lowers costs. Mining of the sunrise orebody began in 1995 and is currently mining in fresh volcanics and banded iron formations. In this study, the blasting vibration signals monitored at a blasting site with different rock masses were used to investigate the attenuation.

Technologies for optimizing drilling and blasting in open pit mines m. The firing sequence of a chevron pattern can radically alter the drilled burden and spacing into the blasted or effective burden be. Blast hole diameter d in mm15 burden b 25 to 40 x d spacing s 1. Assessment of blastinginduced ground vibration in an open. In a coal mine blast, flyrock traveled 900 feet and landed beyond the permit boundary causing a fatal injury msha, 1990a. Segui julius kruttschnitt mineral research centre, australia. Controlling fume movement following the blast is not possible and the pit will remain closed until the all clear is established. These rules provide a first estimate in the absence of any better data. Optimization of drilling and blasting operations in an. The influence of slope design has an overriding effect on the economics of an open pit mine. In most cases, the productivity rate is influenced by the degree of fragmentation.

Pdf drilling and blasting practices in nevadas openpit mines. Vibration response of the waste rock dump in open pit mine. Paper open access pit wall stability and drillingandblasting. Therefore, accurately predicting the blasting vibration is necessary to ensure slope stability. Rock fragmentation control in opencast blasting sciencedirect. Blast plan a written procedure that details the methods and manner by which a project blaster will comply with pertinent laws, rules, regulations, and contract documents.

Open pit mine planning and design, third edition mining. In opencast mining, where blasting is employed for excavation, the overall cost effectiveness of the production operations is compatible with optimization of drilling and blasting parameters. Case of metlaoui mining basin, southwestern tunisia. Nonetheless, only 2030% of the used energy is served for rocks fragmenting and. Processed ore by minerals for open pit and underground metal mines for the period 1988 to 1997 in the western world. Okubo encyclopedia of life support systems eolss figure 1c. Rock fragmentation depends upon two groups of variables. The hoekbrown strength criteria is a widely adopted approach. The development of a successful control blasting program for an open pit iron mine in hard jointed rock is described. In the illustration that follows figure 84 shows a typical bench cut with two free. The only way to evaluate accurately the cost of explosives, is to examine the effects of blasting and to determine the optimum degree of fragmentation. Open cast mineral resources are quoted as insitu tonnages and mineral reserves are tonnages falling within an economic pit shell. Mitchell pit in the ksm project will have an extremely high engineered pit wall and as such, controlled drilling and blasting must be needed to allow safe operation of the pit. Surface blasters, however, must be aware that toxic fumes have the potential to create hazards in their operations.

Bench blasting is a common blast technique m ost often used for open pit mines. When an explosive charge is detonated, chemical reaction occur which, very rapidly. In this study, the blasting vibration signals monitored at a blasting site with different rock masses were used to investigate the attenuation characteristics of. Loading and transport costs constitute up to 50% of the total operational costs in open pit mines. Non electronic detonators and new blasthole loading techniques you decide author. Bench height the vertical distance between the base of one bench and the base of the overlying bench. Dilution can be a major contributor to poor grade results, and blast movement is a significant cause of dilution and ore loss 1. Drilling production drilling will be done with electric drills with a 15m bench height. Hopkins engineering division, lawrence berkeley national laboratory, berkeley, california, usa j.