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By H. L. Monro

Contribution by B. K. Martust I congratulate the author on his interesting paper. In my view, the establishment of the level at which South African gold output is at some kind of optimum is an interesting though somewhat academic exercise. Contribution by D. M. Hawkins* The thesis of the paper is a very interesting one, but, before it is used as the basis of any firm proposals to restructure the mining industry, which changes may be irreversible, one should be very sure that the basis of the calculations is sound. Contribution by P. J. Niewenhuizen* The hypothesis advanced by Mr Monro that the demonetization of gold in August 1971 introduced a major new policy variable, namely the supply-pricejdemand-price relationships, into the decision making process touches on a matter that has never really been given serious thought by the industry. Contribution by B. G. Kingsman* As a co-worker on the development of an econometric model for supply and demand in the world gold market with Mr H. L. Monro, it would perhaps be useful for me to make some comments on the various points raised in the discussions on his paper.

Jan 1, 1984

By A. Eilers

COMPOSITION OF CHARGES AND CONSUMPTION OF FUEL AT VARIOUS WORKS. A MARKED peculiarity of most of the smelting-works of the Far West is the looseness with which accounts of the operations are kept. Indeed, probably over half of the works do not keep any detailed accounts at all, the yearly gross statement of profit or loss being considered sufficient for all purposes. The reasons for this must apparently be sought in the as yet unsettled state of all business relations, and in the deplorable fact that only in isolated cases educated metallurgists are in charge of the smelting-works. Continual and regular assays of the ores, by-products, and slags, are almost unknown, so that it is impracticable to ascertain, even approximately, the losses in the smelting processes. Of cases where regular accounts are kept of the quantities of ore smelted, of the composition of charges, and of the fuel consumed, I know only two or three. Under these circumstances it is extremely difficult to collect figures which cover the operations for a considerable length of time, and which are so valuable for the metallurgist, who wishes to get an insight into the economy of smelting operations, as shown by practice. Figures obtained by personal observation, which can of course cover only the brief space of the visit of the travelling metallurgist, must, therefore, be made to replace the more valuable data. The writer has had occasion, during the last and the preceding summer, to visit the larger number of the Western lead-smelting works, and offers, in the following pages, such data relating to the economy of lead-smelting in the blast furnace at various works, as he has been able to obtain. The only object in doing so is to place these figures on record, so that they may be from time to time supplemented with other data, which are now wanting. I. EUREKA CONSOLIDATED COMPANY'S SMELTING-WORKS. These works smelt the ores from the mines of the same company on Ruby Hill, Eureka, Nevada. The supply is almost unlimited,

Jan 1, 1873

By J. Pelders, G. Nelson

"Fatigue is a significant concern in the mining industry as it is a causal or contributing factor in many incidents and accidents. Fatigue can be caused by work- and non-work-related factors. There is a lack of information about associations between demographic and other non-work factors, and fatigue. This study aimed to assess associations between demographic, work, living, and socioeconomic conditions, and lifestyle characteristics, and fatigue at a platinum smelter in South Africa. Eight interviews with management and two focus groups with production workers were conducted, and 75 questionnaires were completed by production and other workers. Both work- and non-work-related factors were considered to be causes of fatigue. These factors included overtime, shift work, high workloads, activities performed outside of work, age, race, housing tenure, diet, sleep disorders, stress, and job satisfaction. In general, higher levels of fatigue were reported by younger participants, those who rented accommodation, ate less healthily, had a sleep disorder, and those with high levels of stress and low job satisfaction. As various demographic, lifestyle, and wellness-related factors were associated with fatigue, both work and non-work contributors should be addressed in fatigue management plans. BackgroundFatigue may be defined as ‘a state of impaired mental and/or physical performance and lowered alertness arising as a result of, or a combination of, hard physical and mental work, health and psychosocial factors or inadequate restorative sleep’ (BHP Billiton, 2005). Williamson et al. (2011) define fatigue as a biological drive for recuperative rest. Sleepiness and fatigue are related, and the terms are often used interchangeably. However, sleepiness, more specifically, can be defined as sleep propensity, or a person’s tendency to fall asleep (Hossain et al., 2003; Shen, Barbera, and Shapiro, 2006).Increasing levels of fatigue and sleepiness are associated with lapses in attention, errors, response slowing, fluctuations in alertness and effort, and impaired attention, working memory, long-term memory, decision-making, and creativity (Alhola and Polo-Kantola, 2007; van Dongen and Dinges, 2000). Fatigue is also associated with adverse effects on mood and impulsive behaviours (Alhola and Polo- Kantola, 2007; Minkel et al., 2011; Schwarz et al., 2013). It is a significant concern in the mining industry as it is commonly identified as a causal or contributing factor in many accidents and injuries (Schutte, 2009). Fatigue can also lead to long-term health problems, including digestive problems, heart disease, stress, and mental illness (Shaw, 2003)."

Mar 1, 2019

By Elham Kordzadeh

As the world’s reserves of coarse and high-grade iron ores continue to shrink, beneficiation is becoming increasingly important. The resulting concentrates cannot be used directly as feedstock for iron making, but require an additional agglomeration step. Pelletizing is preferred, because the uniform chemical, physical, and metallurgical characteristics of pellets make them a more desirable feed for the iron making processes. The heat hardening or induration of pellets is typically done in shaft furnaces, grate-kiln systems or on straight grates. Rotary kilns were originally developed in the late 19th century for Portland cement production [1]. The main development work for the successful adaptation of the process to the thermal treatment (induration) of green balls from iron ore was performed by Allis Chalmers in Milwaukee, Wisconsin, USA in the 1960’s [2].The straight grate process, which was first used in 1955 at Silver Bay, Minnesota, was a dedicated development with the aim to pelletize and indurate magnetite (taconite) concentrate [2]. There are various important technical and economical distinctions between the two pelletizing technologies. The most important differences include that a grate-kiln has three distinct pieces of equipment, a preheat grate, a rotary kiln and an annular cooler, whereas in the case of a straight grate, the entire indurating process is done on one piece of equipment only. In addition, both technological solutions have differences in their recuperation systems, direction of air flow in drying, number of burners, form of pellet movement, etc., which cause differences in raw material suitability, process control, economical aspects, plant operation and product pellet quality.

Oct 30, 2017

By Jon C. Volkwein

Advances in mining technology have enabled deeper seams of coal to be mined from the surface. Highwall mining is frequently used to mine areas at the perimeters of a surface mine when removal of the overburden becomes uneconomical or threatens environmentally sensitive surface features. At the same time, advances in materials and technology have enabled highwall mining of coal that create blind headings over 300 meters in length. Deeper surface mining and deeper highwall penetration depths have lead to more frequent encounters with methane gas. While this coal is remotely mined from the surface, underground ignitions of methane have propagated to the surface and injured miners. Methods described in this paper show how this hazard can be correctly monitored and controlled for auger type highwall mining machines. Research indicates that small quantities of gas liberated during mining migrate to the face, creating higher gas concentrations than would otherwise be expected. Using the same principles that cause the gas to migrate to the face, researchers have shown that inert gas introduced at the collar of the hole can inert the entire hole, thus ensuring safe conditions for mining.

By R Shaw, T T. Neidel, C Adams

Sampling equipment manufacturers endeavour to ensure that the mechanical equipment installed in sampling systems are designed and manufactured to adhere to the requirements of the International Organization for Standardization (ISO) or other standards relevant to the application. The mechanical parameters necessary to achieve these standards can be well controlled and requirements such as constant speed can be met through good mechanical design and engineering. However, when the equipment is installed and put into operation, the ISO compliance of the system is out of the hands of the equipment manufacturer and handed to the operator, who may be a generalist control system integrator.Making a sampling system perform according to standards, and being able to monitor and report on compliance require that the sampling system knowledge and the control integration is combined and applied in an integrated approach. Using a dedicated library of control routines developed for sampling can change a system from having compliant equipment to being a compliant system. The library has to include monitoring of relevant parameters and control and reporting on sampling parameters.CITATION:Neidel, T T, Adams, C and Shaw, R, 2014. Control and monitoring of International Organization for Standardization compliance for industrial sampling systems, in Proceedings Sampling 2014 , pp 121–126 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 29, 2014

By Florian Kongoli

Converters have been playing an important role in the extraction and processing of metals ever since the first type of converter was invented about 100 years ago. Historically their operation has been mainly based on the experience of talented operators rather than on strict control and optimization technologies. However, in the new realities of unavoidable necessity to increase productivity and in the conditions of diversification of primary materials from various geographical areas, improving control and optimization techniques have become indispensable. In this paper a review of the authors? previous work in terms of improving control and optimization of converter operational practices related to magnetite content and precipitation, slag and metal blows, problematic and dangerous elements such as As, Sb etc. has been described by highlighting the advantages that the new control and optimization methods and tools bring to everyday converter practices. Several examples are given and future work is underlined

Jan 1, 2005

By Barry J. Morash

The over-all slope angle of between 55 and 60 degrees at the Adams Mine necessitates control blasting on the final pit walls. The control blasting techniques used are pre-shearing and buffer blasting. Pre-shearing with 2'I2-inch holes on 5-foot centers is used in areas where jointing and rock type are not conducive to smooth stable walls. Buffer blasting with 12'/4-inch holes is used in areas where the rock is competent. Control blasting adds to the operating costs, but can result in substantial savings in increased slope angle and reduced stripping.

Jan 1, 1978

By George McIvor, Bill Thompson, Don Whitmore, Brad Rhude

"In 1972 Manitoba Hydro decided to develop the hydro electric potential of the Nelson River. This program included the construction of the Jenpeg Generating Station at the point where the channel of the Nelson River discharged into Cross Lake. The Jenpeg station serves two primary functions: 1) Provides a control structure for the regulation of Lake Winnipeg.2) Acts as a 126,000 kilowatt hydraulic generating station."

Jan 1, 1992

By Valencia P. Félix

El texto refiere la labor de control de calidad desarrollado en el minado de óxidos y sulfuros del yacimiento minero Cerro Verde. Este procedimiento implica la actualización de los límites mineralizados y leyes, a fin de generar información al Ingeniero de planeamiento y garantizar que el contenido metálico no difiera del contenido en la explotación. Asimismo especifica características de la ganga y elementos accesorios como contenidos de fierro, manganeso y molibdenita durante el proceso de control del mismo.

Oct 14, 1980

By Ernesto Sirvas Bello

El presente texto señala el control geológico en la explotación de minas de oro. Dicha operación se divide en el control de las operaciones subterráneas y las de tajo abierto. Las primeras se relacionan con la explotación de estructuras vetiformes y las segundas con la mineralización diseminada de oro de “baja ley. Así también, se revisa las reservas porque se considera que en este aspecto ya no interviene el control de calidad, la cartografía, muestreo, dilución pérdida de oro por operación y los procesos de reconciliación de resultados. Finalmente, se muestran ejemplos de problemas que afectan el control de calidad y sus posibles soluciones.

Apr 26, 1999

By Álvaro Jubera, Fabricio García, Héctor Painevilo

Esta investigación busca demostrar que la aplicación de tecnologías de la industria 4.0, permite una mejora en el control de los planes de minado en tiempo real. Este estudio presenta el uso del Control de Intervalo Corto (SIC), aplicado al cumplimiento del plan de minado en una operación a tajo abierto en el norte de Chile. Para esto, se utilizó una tecnología innovadora, llamada "TIMining Aware", que consiste en un gemelo digital que crea una representación virtual de la mina y de sus operaciones en campo, permitiendo que equipos de operaciones y planeamiento puedan monitorear la ejecución del plan en tiempo real, logrando así, reducir las desviaciones y ocasionando un mejor desempeño operativo global.

Sep 29, 2023

By Osbel Yzaguirre, Pio Carrasco

En la presente investigación busca controlar la dilución del mineral realizando una explotación del tajo con un ancho de minado adecuado (0.6 m) y la selectividad de mineral económico y no económico utilizando el método minado corte y relleno ascendente realizando un análisis comparativo de la evaluación de malla de perforación actual y la evaluación de mallas de perforación nuevas, Tipo 2-1 y Tipo Zig-Zag, donde en esta propuesta se ha obtenido favorables resultados con la malla de perforación implementada puesto que se observa una reducción en el costo de voladura y costo de sostenimiento además de lograr la reducción del porcentaje de dilución.

Sep 29, 2023

By Roberto Palacios, José Morán, Cristian Fernández

El presente trabajo cuenta con la experiencia, metodología y tecnología desarrollada en minera aurífera retamas frente al problema de la sismicidad inducida por el minado y los controles estratégicos y tácticos a seguir para reducir los eventos microsísmicos y dar sostenibilidad a las operaciones mineras, priorizando la seguridad de nuestros colaboradores e infraestructuras de la mina. En este trabajo, se muestra la metodología y controles de mitigación que se utilizan para reducir los incidentes por impacto de los eventos microsísmicos en las operaciones mineras. Haciendo una mina segura y sostenible.

Sep 29, 2023

By Yhonny Paul Ruiz Dioses

El control de leyes es un proceso que determina las zonas económicas durante las labores de explotación minera. Para calcular los recursos geológicos que pasan a ser reservas y pueden ser explotadas con beneficio económico, se requiere de estudios que delimiten los volúmenes de mineral que serían enviados a la planta para su tratamiento. En ese sentido, el presente texto señala cómo el software minero RecMin puede beneficiar al área de control de leyes, muestra las funcionalidades que posee RecMin para manejar la etapa de producción y refiere la importancia del control de leyes y la implementación de un sistema, ya sea comercial o free para su ejecución.

Apr 1, 2014

By Marino Gaspar

La tendencia mundial va hacia lograr una minería automatizada que permita mantener la información en línea, garantizar la continuidad operacional y mejorar la producción y seguridad de los procesos, toda vez que la automatización aumenta la productividad y reduce los costos de producción a través de la optimización del uso de equipos críticos. En ese sentido, el objetivo del presente trabajo fue controlar en 5 % la variabilidad del flujo de mineral a lo largo de todo el proceso productivo de la planta, para lo que se usaron tecnologías enfocadas en el internet de las cosas y control web. Así, la corporación incrementa su valor al incorporar las nuevas tecnologías y modelos de gestión en la explotación y procesamiento de los minerales, a la vez que reacciona de forma más veloz y flexible a los cambios en el mercado de los metales.

Sep 20, 2019

By Richard Palape, Nicolás Rojas, Álvaro Díaz

El presente trabajo cuenta la experiencia, metodología y tecnología desarrollada en varios sitios por más de media década, donde en minas con tal nivel de producción y tecnología, se podría pensar que se encuentra todo bajo control; sin embargo, existen oportunidades de mejora para ir a un siguiente nivel al que llamamos Excelencia Operacional Digital. Como se relató, las tecnologías pueden parecer muy completas o robustas, pero normalmente no son adoptadas por los trabajadores. Esta falta de involucramiento tiene diversas causas tales como falta de empatía de parte de los proveedores de tecnología, poco entendimiento e involucramiento de los trabajadores o bajo entusiasmo que causa la tecnología en el día a día.

Sep 29, 2023

By Rojas M. Raúl

Durante el proceso de explotación de la mina Cerro de Pasco y dada la cercanía de la ciudad misma, esta se ha visto afectada por los problemas de vibración del terreno. En este sentido, el objeto del texto es determinar un control de las vibraciones a través de la voladura en el tajo Mc Cune de dicho yacimiento y así evitar daños a las construcciones civiles y labores de explotación subterránea.

Nov 8, 1984

By Luis Porras T.

La explotación de minas de cielo abierto requiere de la estabilidad de los taludes puesto que estos aseguran el eficiente minado de los bancos inferiores y garantizan las condiciones para los servicios auxiliares. Por ello, el presente trabajo señala el método de voladura controlada como el más adecuado para la estabilidad del talúd en explotaciones de límites finales. Dentro de este método, el criterio de velocidad pico de partícula refiere el grado de vibración producido en el terreno por los disparos, ajustándose en el cálculo de carga de los taladros. Sin embargo, en el caso de la mina Toquepala y por razones de índole estructural, el método de minado se aplica de forma moderada la zona Este. Asimismo las condiciones de este método quedan supeditadas a las condiciones geológicas, la infraestructura que se desea proteger y a los servicios auxiliares a complementarse.

Aug 26, 1988

By César Fuentes Líbano

El presente trabajo describe el tratamiento que realizó la refinería de zinc de Cajamarquilla en sus afluentes para preservar el medio ambiente. Para ello, la construcción de dicha refinería ha establecido una serie de reglas precisas basadas en el avance tecnológico y la acción contra el medio ambiente de los desechos. Es decir, la refinería fue diseñada y construida con la tecnología más moderna, garantizando que sus efluentes cumplan los requerimientos más exigentes de preservación del medio ambiente.

Nov 8, 1982