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By N. Schmitz

This paper explains how new digital solutions improve reverse circulation drilling operations. Upgrading field-proven reverse circulation drilling (RCD) rigs with new digital technologies enables semiautomated drilling, with upgrade options for fully automated & remote drilling. Key elements of the improvements are electrically controlled valve systems, process instrumentations, a state of the art machine controller and drilling operation via a touch control panel. Automation of core processes, such as adding drill pipes, reduces set-up times, increases machine uptime for drilling and as a result efficiency. While drilling, sensors provide continuous feedback, which is used to automatically adjust e.g. the weight on bit to the optimum; resulting in an increased rate of penetration and less wear and tear. While in the past hydraulic power packs (HPU) have typically been operated at a constant high-performance level with related high fuel consumption, a new interface between the machine controller and the power unit regulates the HPU performance exactly according to the actual drilling operation needs. This leads to significant fuel consumption reduction. The safety benefits of the digital improvements are the ability to remotely operate the rig in challenging site conditions via a mobile operator panel.

Sep 8, 2021

By Charles Pretorius

Electronic Delay Detonators (EDDs) with remote wireless programming and initiation capabilities have been successfully used for almost two years now. This system has been used in blasts mainly in South Africa, but also in South America and other countries in Africa. Initially the industry was slow to accept the idea of remote programming and blasting. The advantages were not fully understood and there were some safety concerns. With close to 200 successful blasts as a reference, a much better understanding exists. The advantage of such a system becomes even more significant when the programming of the detonators is digitally integrated with the blast design software as used by the Blast Engineer. It is now possible to import a survey file into the blast design software, to do the blast design using actual hole positions and to then export the designed firing times directly to the detonators down the hole via remote wireless communication. Mines that have been exposed to this technology favour it to the extent that wireless centralised programming is becoming the norm against which other electronic delay detonator technologies are measured.

Jan 1, 2005

By Benjamin Cebrián, María Gil, David Flores

In many occasions during the Mining operation life, blasting engineers find different and controversial results of fragmentation, dilution or wall control for the same geotechnical domain and blast design (pattern and explosive charge). Most of the times, the difference between same blast designs is not measured, not controlled. Once a blast designed is defined, the most important part of the process after that is the implementation of every step of the blast on site. Almost nobody is measuring it, controlling it, but just controlling implementation is possible to relate blast design with results in a consistent way, to optimize the full process of D&B. Controlling implementation not only per event but also to check and change trends and decision-making is paramount for optimization and saving millions of extra costs every year. The lack of resources and the hardness to manage all the info created every day in a blast make this process very tough and difficult to maintain in long term. The use of new technologies on site and software that allows a best, more consistent and continuous control of blast implementation have been proved to be the key for optimizations and cost saving. This document shows the evolution of drilling and blast digitization process, savings and trends in a mine, using new technologies that creates business opportunities and general improvement of D&B process.

By Benjamín Cebrián, David Flores, María Rocha Gil

This document shows the evolution of drilling and blast digitization process, savings and trends in a mine, using new technologies that creates business opportunities and general improvement of D&B process.

Feb 1, 2020

By Sushil Bhandari, Amit Bhandari

Drilling and Blasting are core operations in a mine. They impact all the downstream operations and their costs. Digital technologies exist for optimizing both drilling and blasting for many years. However, these technologies have largely been non-integrated and non-real time. This gap results in sub-optimal drilling and blasting operations. Also traditionally focus has been on optimizing individual areas (drilling or blasting and subsequent subsystems). Industry has largely lacked real time or near real time integration available to the user in the field and in the office. In this paper, a case study is presented of a large global cement company using a cloud and mobile based platform across 17 of their mines consistently over a large number of users over a period of over two years. The use of a blast platform is detailed which include blast designs, blast data collection and the trends in terms of results. On the drilling side, this paper describes the ability to capture drill logs, plod reports etc. Also actual drilling information in the field using a mobile device and its real time synchronization with a blast designer to provide visibility of expected fragmentation and vibration levels based on the drilling done. Key parameters such as hole ID, design depth, actual depth, hole status, designed and actual charge (length and weight), designed and actual stemming length are captured. The case study also highlights the challenges in technology adoption and implementation in mining in drilling and blasting. Making drill and blast results predictable should be the desired direction. Also digital technology tool adoption has been seen at the biggest miners – not so much in mid-sized miners or drill and blast contractors. Benefits of this platform on the safety side are highlighted including predictions on safety parameters and appropriate alerts if blast safety parameter / clearance zones are not met. The safety parameters are made available visually to the operator using maps and / or on drone images. Future possible improvements in the digital technology platform at the site are also highlighted including greater possible automation.

By Alfonso Núñez

There are many assets on a typical industrial site that are not monitored continuously by a SCADA system or the DCS. Many of these assets are critical and must be running correctly for production to meet its targets. Most companies schedule inspections of these assets regularly by sending skilled operators to the field who take notes using paper and a clipboard. There are many advantages related to the digital transformation of operator rounds. In particular, the collection process is supported by digital prompts and the data — once it is collected — is automatically routed to a database and made readily available to all the software applications and stakeholders that need it.

Sep 29, 2023

By A. M. El Shafey, Ahmed W. Hussein, Ibrahim M. Gaafar, Mona M. Fawzy, Mohamed Diab, Mohamed S. Abu El Ghar

The Quaternary stream sediments of the Diit area, southern Red Sea coast, Egypt, were mineralogically studied for their content of economic heavy minerals. The study area covered approximately 450 km2 and included three main parts: Wadi and Delta Diit, as well as Diit lens. The mineralogical investigation revealed that these sediments contain considerable amounts of placer ilmenite, magnetite, zircon, sphene, apatite, garnet, and rutile. Also present, in minor or trace amounts, are uranothorite, monazite, xenotime, fergusonite, khatyrkite, and gold. The magnetic fractionation tests, supplemented with the XRD and SEM mineral analyses, indicated the presence of Fe-oxide minerals as wuestite, hematite, and maghemite accompanied with magnetite as products for hand magnet separation. Ilmenite separation was carried out using a high intensity magnetic separator at a current of 1 A, while the paramagnetic minerals (e.g., garnet, pyroxene, amphibole, epidote, monazite, xenotime, and fergusonite) were separated as magnetic fraction at a current of 3 A. The non-magnetic minerals (e.g., zircon, apatite and rutile, uranophane, uranothorite, gold, and khatyrkite) were obtained at 3 A current. On a mineralogical and geochemical basis, the present work suggests that Diit stream sediments should be considered as a potential source for Ti, Fe, Zr, Zn, and Cu after the physical upgrading processes for concentrating the minerals carrying the aforementioned economic elements.

Jan 21, 2022

By Vsevolod Krivobok

IT is generally recognized that "low temperatures" have a definite effect on the properties of metals and alloys. Furthermore, it is also generally understood that the effect is decidedly adverse. The possibility that the same low-temperature treatment might be employed for the purpose of improving certain properties of the .alloys has received less attention until recently, and the experimental and theoretical knowledge consequently is meager. The effect of low temperatures may be studied in two ways: by studying such properties as tensile strength, hardness, impact resistance, etc., at low temperature, and by studying the properties of alloys at room temperature after these alloys have been subjected to a low-temperature treatment. Even in the latter case, certain properties will differ materially from the same properties obtained on identical material but without cold treatment. In other words, subjecting alloys to cold treatment results in an irreversible change in mechanical properties. Changes of this character are usually indications of the appearance of a new phase or phases, and would be likely to occur in alloys which, either by virtue of their composition or by heat treatment, are retained at room temperature in a metastable condition. Consequently, studies of the effect of low temperatures logically should be conducted from the physicochemical point of view, since the results of such studies not only would furnish metallurgists with interesting theoretical data but would clearly indicate the classes of alloys that would hold promise of improvement, and, possibly, of new applications. As the present investigation deals with chromium and chromium-nickel alloys of iron of the stainless variety, it has been thought desirable to present the data concerning low-temperature properties of these alloys, available from the most recent and most comprehensive work of H: S. Russell.' A summary, of these data is given in Table 1. The data are confined to a limited number of alloys of the type dealt with in the present

Jan 1, 1931

By J. A. Eisele, D. J. Bauer, L. E. Schultze

Approximately 100 million mt of magnetic reject tailings, which contain apatite and about 1% yttrium and rare-earth elements, exist in the eastern U.S. as a result of iron ore mining operations. At the present time, no economic process is available for recovering yttrium from this material. The U.S. Bureau of Mines (USBM) studied the problem to determine if an effective low-cost method could be found, thereby increasing our domestic yttrium reserves. [Fig. 1] is a line drawing of a photograph taken during microprobe analysis of a sample of the tailings, and shows the distribution of yttrium. Typical analysis of this material is 0.14% yttrium and 1.1% rare-earth elements (mainly lanthanum through neodymium). Over half of the yttrium is present as a hydrated Ca-Y silicate deposited along interfaces in the grain structure; whereas, the remainder of the rare-earth elements occur as Ca-Fe-RE silicates. The remaining yttrium and rare-earth elements are in solid solution with the

Jan 1, 1977

By Mohsen Sanai, Paul Gefken

"SRI International has developed and patented* a castable dilute explosive tile @ET) that offersunique advantages over conventional high explosive. The primary advantages of DET are that itsdetonation pressure can be adjusted over a wick range and its impulse can be controlled independently by adjusting its thickness and configuration. Because DET has a much lower detonation velocity than conventional explosives, the pulse duration produced by DET is as much as 10 times longer than the pulse duration produced by conventional explosives for equal explosive weights. These features of DET present several advantages to the mining industry. For example, DET can be tailored so as to control fragment size and distribution to enhance extraction of desired elements from ore or breakup of specific regions."

Jan 1, 1995

By Michel David

"The usual complaint of mines is that grade does not match exploration expectations. Quite often, more tons are mined than expected but at a lower grade. This can be seen as dilution. Geostatistics can help predict which dilution can be expected both in terms of grade and tonnage for different mining methods.The usual vocabulary of geostatistics speaks of block distribution; block variance, size effect, information effect, all terms which say very little to the practitioner. In f act, all this can be rephrased in terms of dilution .In this paper, the following is presented - an example which shows how reserves change with the size of selection units and number of samples taken, and tables which show the dilution that are bound to happen when dealing with the commonly encountered log-normal distribution. Finally, the paper shows how grade tonnage computations should be made in the case of an arbitrary distribution. IntroductionGeostatistics progresses more and more rapidly if one judge s by the number and quality of papers published in Mathematical Geology or at APCOM meetings. More and more case studies describing successful applications are published (David et al., 1986)(Kwa and Mousset-Jones, 1987). It is estimated that more than 270/0 of the gold mines around the world use geostatistics. There is still, however, a lot of resistance from the remaining 73%. Geostatistics has more formulae and equations than it needs to reach year 2000. We will be well into the third millenium before all the models available now are actually used. The progress may come in the form of finding better ways to present known statistical results and getting away from the jargon of geostatisticians. One example may be in trying to explain how we can answer the most common plea of the mining industry: production grade is not what was expected in the feasibility study."

Jan 1, 1988

By Pitkajarvi J

Waste rock dilution causes mill feed grade to be lower than mineral resource grade. In nickel mines relative grade decrease (dilution) may be tens of per cent because of irregular ore boundaries and weak wall rocks. Five per cent dilution costs millions of dollars annually in medium size underground mine. In Outokumpu Group selective bench and fill stoping, cable bolting/shotcrete-skin support and fast ore boundary definition (OMS-logg in-hole logging or sludge sampling) are the key tools in dilution control. Commitment of the whole organisation to keep dilution low is also needed. Dilution sources and effects are discussed with examples of the dilution control methods applied in Outokumpu mines.

Jan 1, 1996

The economic viability of many Southern African massive mining operations is threatened by excessive dilution. In many operations currently in progress, some stopes are experiencing as much as 115 per cent waste ingress reporting to drawpoints. This paper examines the magnitude, causes and types of dilution and presents a set of general principles for the control of dilution in massive stoping operations.

Jan 1, 2000

By David Flores, Benjamin Cebrian

Gold mining require high levels of dilution control due the high value of ore. These types of operations employ short benches, which are suitable for ore control, lower displacement and more representative block models. However, shorter benches makes fragmentation by blasting difficult because blast designs tend to be stiff in regards to burden/bench height ratio. This is especially relevant in hard, massive ore bodies where usual drilling diameters lead to poor energy distribution. In regards to control ore loss and dilution, there are different techniques to minimize both, which include: panel blasting, buffer blasting to muck piles and differential loading of areas of the blast bench. All of them should be sequenced with appropriate displacement along the ore/waste contacts. 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.

By P. D. Soares, H. R. Bullis, R. A. Hureau

"Echo Bay's Lupin Operation has produced more than 2.15 million ounces of gold since start-up in 1982. The mining method used to the£ present time has been longhole open stoping using trackless equipment. Because direct measurement of the open stopes has not been possible until recently determining the exact quantity of unplanned dilution in previously mined stopes has not been possible. Estimates of dilution hove been mode using comparisons between production tons and grades against ore reserve tons and grades.This paper discusses tracking of grade and tonnage measurements from reserve estimation through production. Comparisons between estimated and actual tons and grade are presented~ along with a brief description of methods used at the Lupin operation to control dilution."

Jan 1, 1994

By A Vakili

Dilution is associated with considerable direct and indirect costs in underground open stoping operations. As shown in previous works, an improved ability to predict dilution enables the economic risks associated with unplanned dilution to be reduced. Depending on the width of the orebody and depth of mining, the economic performance of an open stoping operation can become even more sensitive to dilution. It is shown in several well-documented studies that as little as 1 per cent of additional dilution can impose millions of dollars of lost profits per annum. Optimisation of a stoping operation is therefore largely dependent on the ability of the operation to minimise dilution. This can only be achieved through sensible analysis of past and future performance of mined stopes using the most appropriate recent available technologies and tools. This article presents a new design process that utilises advanced geotechnical numerical modelling and various other analytical tools to assist with a more robust mine design of open stoping operations. The focus of this design process is on geotechnical factors affecting dilution during the life-of-mine. A recent application of this optimisation method for a mining operation is presented in this paper as a case study. Through the application of this method and various other operational improvements, the mine was able to deliver more consistent production and lower operating costs over its life-ofmine outlook and was able to reduce dilution by up to 50 per cent and achieve sustainable record high production rates.

Mar 29, 2023

By C Nyoni, T Nguyen, C R. W Seymour, G D. Dempers

Unplanned dilution directly adds cost to production from mining, milling, tailings disposal and administration. Additionally, unplanned dilution decreases the productivity, profitability and may affect the planned life of mine. Identifying and quantifying the potential for unplanned dilution allows optimisation of the mining plan and mining practices to minimise the adverse impact on productivity and the cost of production. The Dilution Rating System (DRS) has been developed to more accurately predict dilution thickness and the variable potential for dilution, from individual stopes to life of mine planning. The DRS utilises the methodology developed for the Mining Rock Mass Model (Seymour et al 2007, Jenkins et al 2009) to generate a three-dimensional dilution rating model, which is then calibrated against stoping performance. Dilution can be predicted more accurately and the parameters affecting dilution can be determined and minimised through improved mining techniques, for example blasting and ground support design. Potential high dilution areas can be identified in the planning stages of the mine and systems put in place to mitigate the risk of excessive dilution. This paper presents the methodology used to develop the DRS and then successfully predict dilution for both the hangingwall and footwall of stopes at the Gara Gold Mine. This has enabled the expected dilution to be more accurately predicted and mitigated where possible thus reducing unplanned dilution.

Mar 15, 2021

By I C. Carrasco, V G. Mirada, J F. D Domingo, F S. Leite

This paper investigates ore loss and dilution produced by rock movement in bench blasting. A total of four blasts, in which electronic detonators have been used, were monitored in Cobre Las Cruces Open Pit Mine (FQM Ltd) in Gerena (Sevilla, Spain). Rock motion has been obtained in 137 points of the free face and 6 points inside the block. Multiple liner regression has been applied to predict rock motion and estimate ore dilution as a function of hole coordinates, rock contacts, powder factor/hole, amount of explosive per blasthole, burden, spacing, hole length, stemming length, explosive energy, hole row, subdrilling, blast sequence, stiffness ratio, blasthole distance to free face, rock density and Young’s modulus. The model is statistically significant with a determination coefficient over 0.8. Rock motion measurements in 31 more points have been used to validate the model and to show a reduction in ore dilution.CITATION:Domingo, J F D, Leite, F S, Mirada, V G and Carrasco, I C, 2015. Dilution, ore grade and blast movement calculation model, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 71–78 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By M. Javier

In business mining, dilution is the result of the operating parameters that occur too often and cause serious consequences to mine performance, questioning TO WHOM BENEFITS DILUTION. Mining persists in changing perception of real meaning of dilution. The lack of interrelation between mineral processes and nature compromises the understanding of dilution; this absence of interrelation occurs due to the misinterpretation of nature, otherwise, Geomimic could be helpful to filling the gap of misinformation. NATURE provides LIMITED metals in low content deposits; it is a challenge to obtain them. Nature never considers dilution. Furthermore, though dilution is a human concept, dilution is accepted and promoted. Reality of dilution is in its errors accumulation that translates into technology level or status applied in nature. It is doubtful that dilution can continue surviving if it is ?meaningless?. It will discourse: Is dilution illegal? If the change occurs in the prediction of mining will prevail a different destiny, it is important to touch the cores of the business; otherwise, it would represent repetition of the same ?negative? effects, as usual. Mining defines many losses during the disturbance of nature, from NPV elaboration to the metal recovery to commerce, demanding BETTER DESIGN. This paper introduces and applies MANAGEMENT BY LOSS, as first steps, to limit risks and uncertainties in mining. As result, the management of dilution will be obtainable under mining practices which promotes its character of SUSTAINABILITY.

Feb 23, 2014

By George J. Simandl, Donald F. Gunning

At the beginning of the 20 century, British Columbia produced a wide variety of quality dimension stone products for both domestic and foreign markets. The industry flourished until the 1930s when most of the producing quarries closed as a result of the Depression. During the 1990s, British Columbia experienced the resurgent North American dimensional stone production trend. The industry benefited from increased prospecting activity and from substantial new investment in processing equipment, particularly in the granite sector. These activities resulted in new quarry developments, the reopening of abandoned quarries such as on Granite and Fox Islands <www.quadrastone.com>, and a renaissance in downstream value-added activities. British Columbia has reestablished itself as an important, reliable and innovative source of high-quality stone products.

Jan 1, 2001