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By A Rantala, C Cruickshank, I Muzinda, O Haavisto, J Timperi

The production at First Quantum Minerals’ (FQM) Kevitsa Mine, located in northern Finland, commenced during the second quarter of 2012. Presently, the mine processes approximately five and half million tonnes of ore annually, producing nickel, copper and platinum group metal (PGM) concentrates. In order to support fast production ramp-up and optimise the performance of flotation thereafter, an extensive advanced flotation control solution was implemented by Outotec in collaboration with FQM Kevitsa.In addition to basic process instrumentation and process control, each of the 14 Outotec 300 m3 and another 26 cells, ranging from 20–160 m3, have been equipped with state-of-the-art systems providing froth image analysis and automatic froth speed control. Also, the flotation cell levels are stabilised with advanced feed-forward level control.The online analyser provides key feedback information of the process performance for the advanced process control (APC) system. Based on this information, APC system defines grades and recoveries according to rules defined by Kevitsa process metallurgists. This system executes the control strategies for optimising the production of concentrates.Throughout the implementation and support phases, specific and intensive attention was paid to ensure plant personnel gained full understanding of interacting with the system and how to incorporate their process experience and skills to optimise the APC strategy. This level of expertise is also a valuable asset in understanding the APC system’s contribution to the overall performance of the plant as well as providing the ability and confidence to define key performance indicators used for continuous assessment. The experiences and results from site achieved so far are discussed in this paper.CITATION:Rantala, A, Muzinda, I, Timperi, J, Cruickshank, C and Haavisto, O, 2014. Implementation of advanced flotation control at First Quantum Minerals’ Kevitsa mine, in Proceedings 12th AusIMM Mill Operators’ Conference 2014 , pp 369–378 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 1, 2014

By N. Wachgama, J. P. T. Kapusta, R. U. Pagador

The Thai Copper Industries smelter (Thai Copper) is located some 200 km southeast of Bangkok near the MapTaPhut deep sea port in one of the industrial centres of Thailand. Although construction of the complex started in the mid 1990s, the smelter, acid plant and refinery were completed in 2004. Thai Copper is a state-of-the-art copper smelter processing imported concentrates with a total yearly capacity of 165,000 tonnes of cathodes. It employs the El Teniente Technology where concentrates are blended and smelted continuously in a primary smelting reactor to produce high grade matte or white metal. The white metal is converted in batches to blister copper in Hoboken siphon converters equipped with Air Liquide Shrouded Injector (ALS I) Technology for sonic injection of oxygen enriched air. Final refining is carried out in two anode furnaces prior to anode casting and electrorefining. Thai Copper and Air Liquide Canada executed a technical assistance agreement in late 2005. Pre-commissioning of the shrouded injectors took place in July and November 2006 while hot commissioning occurred in December 2006. This paper presents the major technical aspects of the joint commissioning, including the establishment of operating practices specific to shrouded injection converting. Preliminary results of this first commercial implementation of ALSI Technology in copper converting are also provided.

Jan 1, 2007

By B E. De Gee, N Viviers, A Naidoo

In 2013 the Mopani Copper Mine Mufulira plant in Zambia embarked on a project that was aimed at improving concentrator recoveries. The project commenced with the automation of the milling and flotation circuits. This involved the installation of new instrumentation, namely measurement devices and actuators, and the connection of these to new programmable logic controllers (PLCs).The infrastructure changes were followed by the implementation of basic proportional-integral-derivative (PID) controllers on the PLCs. Supervisory control and data acquisition (SCADA) interfaces were also implemented to allow for switching between controller modes, inputting of setpoint variables and to provide a visual display for process monitoring. The final phase of the project involved the installation and commissioning of advanced process control (APC) solutions on the milling and flotation circuits. This work was carried out by Mintek over 21 on-site days. The APC solutions included the MillStar and FloatStar suites of advanced controllers.The MillStar control suite focused on stabilising the mill feed and mill discharge on the two primary mills as well as the flotation circuit feed. Mintek’s CyLas instruments, which provide a measurement of the hydrocyclone underflow angle, were also installed. The measurements were incorporated into the discharge stabilisation control on both milling circuits. The FloatStar level stabiliser controller provided flotation cell pulp level control on fourteen cells, including two columns.Performance tests showed that the Mintek APC system stabilised the mill feed and mill discharge while ensuring the process remained within operational constraints. The MillStar control system utilised the CyLas instrument to prevent roping on the hydrocyclone underflow. This was not always achieved under normal operation. Additionally, the flotation section was stabilised as a result of improved level control by the FloatStar control system.Performance comparisons showed that the Mintek control system improved the operation of the milling and flotation circuits resulting in a greater copper recovery.CITATION:Naidoo, A, De Gee, B E and Viviers, N, 2014. Implementation of an advanced milling and flotation control system at Mopani Mufulira copper mine, in Proceedings 12th AusIMM Mill Operators’ Conference 2014 , pp 363–368 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 1, 2014

By D. Sagara, V. G. Makhado

"A model based control strategy was implemented at Loulo Gold Mine in Mali, to stabilise the thickener underflow stream density. This stream acts as the feed to the leaching circuit. pH control of the leaching circuit was integrated with the model-based controller due to slow process dynamics that are not suited to PID control. The controller performance was quantified over a period of 6 months, and was compared to the performance before implementation. The model based controller reduced process variability for both thickener underflow density and pH considerably, and resulted in a reduction in flocculant and lime consumption of 9.32 and 6.55%, respectively. INTRODUCTION Reagent consumption in gold processing plants significantly contributes to the total operational costs. In a typical Carbon-in-pulp (CIP) circuit, the reagent consumption associated with leaching, adsorption, elution and regeneration contribute to approximately 15% of the total operational costs (Stange, 1999). At Loulo Gold Mine, the reagent consumption associated with leaching, adsorption, elution and regeneration contributes to 6% of the total operational costs. As such, a reduction in reagent consumption will present a significant opportunity for savings on operating expenditure. Variability in feed ore characteristics results in continuous changes in steady state operating regions, which presents process control challenges as a result of the long residence times in some of the process units associated with gold processing plants. Overdosing often occurs in the presence of process variability to ensure safe operation and to maintain recovery targets. As a means of reducing reagent consumption and accounting for significant changes in the feed to gold plants, some of the plants have resorted to improving their process control strategies around their circuits. This paper focuses on the implementation of a model predictive based controller at Loulo Gold Mine on their thickener and Carbon-in-leach (CIL) tank to: •,stabilise the thickener underflow density, and •,the CIL tank pH."

Jan 1, 2017

By M Wortley, J McKay, D La Rosa, O Guyo

It has been a generally held concept that crushing operations were, by their nature, too simple to benefit from the implementation of advanced process control. The commissioning of an OCS¬ expert control system and image-based oversize detection system, VisioRock, at the Pilbara Iron Tom Price facility are dispelling these notions. A constraint-based OCS¬ expert control system has been designed and commissioned on the high-grade crushing and screening plant along with a vision-based oversize detection system functioning on six product conveyor belts. To date, the expert control has demonstrated the ability to increase production by maximising dynamic constraint utilisation. Dynamic constraint utilisation is a concept developed by Rio Tinto Technical Services for effectively evaluating constraint-based control logic performance. The VisioRock system has been installed and configured and has been operating for a period of several months. Currently, Tom Price and Metso personnel are working to define correct oversize detection thresholds. Details of the plant implementation are discussed.

Jan 1, 2006

By Paul Shimizu

BHP Robinson contracted Minnovex Technologies to implement a Comdale Expert System at their greenfields operation in Ely, Nevada. The expert system has resulted in a significant increase in tonnage. Other benefits have also been realised, including a reduction in operation upsets (having a positive effect on downstream processes, i.e. flotation) and reduced production variances between crews. The expert system is written in a unique manner using trend based logic with minimal hard limits. The result is a robust system that requires minimal operator supervision while producing very high results. The development, success and acceptance of the system can be attributed to the strong team that was assembled for this project. The team not only consisted of BHP Metallurgists and Minnovex but most importantly included operations.

Jan 1, 1998

By Regina Rocha, Miguel Humpire

One of the challenges within unitary mining operations is blasting, which has a significant downstream impact on the following processes, which is why mining companies ensure the results of the blasting process through joint work with explosives specialists’ companies.

Feb 6, 2023

By A. Supomo, H. Resendiz, C. Burbidge

"Freeport-McMoRan Inc. (FMI) commissioned the expansion of the Morenci Metcalf concentrator in 2014. The concentrator included many design and equipment innovations, including the first-of-its-kind Metso Hydraulic Roll Crusher (HRC), variable speed ball mills and variable speed crushers. In addition to the innovative design, FMI commissioned the Metso APC team to design a realistic process simulator and the plant APC. The process simulator was utilized to train operators before commissioning, which led to a smoother plant start up. The plant APC utilized the concept of dynamic constraint control, which controls the feed to the primary ball mills by “pulling” the tons from crushed rock storage bins, which then automatically are filled by the upstream HRC and secondary crushing circuits. The primary ball-mill control also adjusts the water addition to the cyclone clusters to avoid overload and achieve sufficient grind size. The constraints include in-circuit constraints for feeder capacity, screen-deck capacity, ball mill power, cyclone mass flow, pump capacity and pump motor capacity. The APC system was implemented shortly after the start of commissioning and immediately demonstrated increased throughput and an ability to highlight and quantify process constraints and bottlenecks. The following paper outlines the control strategy, discusses system implementation, results and challenges.INTRODUCTION The FMI Metcalf Concentrator is located in Morenci Arizona on the site of the old original Concentrator. The new Metcalf concentrator started operation in May of 2014. This plant was designed for an average of 63,500 tpd (70,000 stpd), increasing the total Morenci concentrator complex production to a nominal 113,400 tpd (125,000 stpd). The process flow diagram is shown below in Figure 1.The process consists of primary crushing feeding a coarse ore stockpile followed by secondary crushing operating in closed circuit with vibrating screen decks. The screen undersize feeds the first of its kind Metso hydraulic roll crusher (HRC) operating in a closed circuit with vibrating screens. The primary crusher is a Metso 60x110 gyratory crusher. Secondary crushers are Metso MP1250 Crushers with variable speed drives. Secondary crusher discharge is recycled to the dry screen feed bin and screened with oversize returning to secondary crushing and undersize feeding the Metso HRC3000. The product from the 3.0 meter X 2.0 meter roll crusher is wet screened with the undersize feeding the grinding circuit, which is comprised of two each 24-foot diameter by 40- foot-long variable speed ball mills running in parallel with each in closed circuit with a cyclone bank of 12 cyclones. The wet screen oversize is recycled to the HRC feed bin."

Jan 1, 2019

By Doug Johnson

This paper reviews the field implementation of R & F Coal's blasting optimization work concerning analysis, prediction, and control of overburden blasting vibrations using site specific measurements and state-of-the-art computer technology. Blasting personnel at R & F Coal had the opportunity to work jointly with Otto Crenwelge of Shell Development Company in his test studies and to later be instructed in the procedures involved in optimizing vibration frequency.

Jan 1, 1988

By D Stow, M Edmondson

Lemington coal mine is operating in an environmentally sensitive area in the Hunter Valley, NSW, Australia. Late in 1999 the southern pit was developed using a series of box cut blasts. After the initial development the area would have been free dug due to the soft, well-jointed nature of the deposit. However, it was decided to trial drill and blast to determine if shovel productivity could be improved to enable an overall mining cost reduction. The initial trial blast results were less than satisfactory with both environmental issues occurring and the desired shovel productivity not being achieved. An audit of the blasts indicated that wet ground and the presence of soft clay inter-bedded with harder rock caused the poor blast results. Also, water-affected explosive product combined with explosive energy loss into soft ground led to flat spots and tight digging in the hard band areas, resulting in the lower dig rates. Lemington Mine and Orica Explosives developed a plan to match the rock with the appropriate explosive type and energy. This resulted in a number of blasts over a six-month period using a new non fuming explosive product, æNovaliteÆ. The results have been excellent with the environmental issues being totally resolved and dig rates improved, enabling reductions in mining costs. This has allowed the mine to continue with their exemplary record of environmental management whilst achieving operational efficiencies.

Jan 1, 2001

By Bilegt Batbold, Bayu Saputra, Chris Batten

The ability to fire multiple blasts simultaneously can provide significant benefits to any open pit mining operation. Reduced blast-related downtime by reducing blast events can increase equipment utilization and maximize material movement. Significant sequencing benefits can also be delivered, associated with reduced equipment relocation. This paper describes the work completed in partnership between Orica and Oyu Tolgoi to successfully demonstrate that combined production-trim and midsplit blasting could be implemented successfully while successfully managing the risk of increased damage to the final walls. The paper details the methodology used to assess key performance measures linked to final wall damage and compares the performance between the following blasting methods. • Free face trim blasting vs. combined production-trim blasting • Presplit blasting vs. midsplit blasting. The results of the initial trial blasts are presented, along with the method agreed by the key site stakeholders for ongoing application. The method used to keep the risk of final wall damage to an acceptable level is explained, along with the benefits delivered to Oyu Tolgoi operations associated with the initial 12 months of application.

Jan 21, 2025

By M. Hamarat

Freeport-McMoRan Copper & Gold (FCX) is committed to preserving and enhancing biodiversity in the areas in which we operate. As a member of the ICMM, FCX is committed to implement the 10 Sustainable Development (SD) Principles throughout our business. FCX is also a member of the Wildlife Habitat Council (WHC), a nonprofit coalition dedicated to protecting and enhancing wildl ife habitat. In alignment with ICMM SD Principle 7 and our Environmental Policy, FCX has set a performance goal to prepare a biodiversity inventory in 2010 and land management plan by end of 2011 for all active mining sites. In 2010 FCX established a Biodiversity Task Force to assist sites in biodiversity management; optimize use of resources around the globe; implement FCX goals and targets; and align biodiversity programs with ICMM principles and guidance. The task force consists of Environment and SD Department management, scientists and engineers from FCX sites, and WHC staff. The Task Force recently issued a biodiversity inventory guidance document to set expectations and provide consistency across the sites when developing a biodiversity inventory and land management plan.

Jan 1, 2011

By G. A. Harrison

The introduction of extra low profile (XLP) mechanized equipment within Anglo Platinum is aligned with the overall New Mining Technologies strategy to focus on continuing modernization of our mining operations` incorporating injury-free production and cost-effective mining technologies. The method allows for the introduction of a suite of ultra-low profile equipment in narrow reef (1.2 m) stoping operations. For the first time it is now possible to achieve total trackless mechanization at these widths and indications are that XLP mining has the potential to add more value when benchmarked with conventional mining and low profile (1.8 m) room and pillar methods. Various mine layouts were tested at different sites within Anglo Platinum and the XLP breast mining layout proved to be the most effective. This paper describes the results of the trials at Waterval Shaft and concludes with recommendations on our future strategy on implementation of XLP technology within Anglo Platinum.

Jan 1, 2006

By Erepan P. C

Flash flotation technology was introduced by Outokumpu in 1985. Considerable success was achieved in other plants with similar operations to OTML. Conclusions from site visits and amenability tests performed on plant samples were that the OTML

Jan 1, 1997

By Gerald Verbeek, Erick Baziw

Cone penetration testing (CPT) is a popular and cost effective tool for geotechnical site characterization. CPT consists of pushing at a constant rate an electronic penetrometer into penetrable soils and recording cone bearing (qm), sleeve friction (fs) and dynamic pore pressure (u) with depth. The measured qm, fs and u values are utilized to estimate soil type and associated properties based predominantly on empirical correlations. The cone bearing measurements are highly susceptible to additive measurement noise for sandy, silty and gravelly soils. This measurement noise results in high peaks due to interbedded gravels and stones and low peaks due to softer materials or local pore pressure build-up. To date there has been little progress in filtering this additive noise aside from ad hoc techniques, which include discarding qm measurements and smoothing/averaging qm measurements. This paper outlines a qm filtering technique which attempts to put structure into the estimation problem. In this case, the dynamics of the cone bearing measurements are modelled within a state-space mathematical formulation and a Kalman filter (KF) is then utilized to obtain optimal estimates of qm. The mathematical details of the qm KF algorithm are outlined in this paper along with the results from a challenging test bed simulation.

Oct 1, 2021

By Gerald Verbeek, Erick Baziw

Cone penetration testing (CPT) is a popular and cost effective tool for geotechnical site characterization. CPT consists of pushing at a constant rate an electronic penetrometer into penetrable soils and recording cone bearing (qm), sleeve friction (fs) and dynamic pore pressure (u) with depth. The measured qm, fs and u values are utilized to estimate soil type and associated properties based predominantly on empirical correlations. The cone bearing measurements are highly susceptible to additive measurement noise for sandy, silty and gravelly soils. This measurement noise results in high peaks due to interbedded gravels and stones and low peaks due to softer materials or local pore pressure build-up. To date there has been little progress in filtering this additive noise aside from ad hoc techniques, which include discarding qm measurements and smoothing/averaging qm measurements. This paper outlines a qm filtering technique which attempts to put structure into the estimation problem. In this case, the dynamics of the cone bearing measurements are modelled within a state-space mathematical formulation and a Kalman filter (KF) is then utilized to obtain optimal estimates of qm. The mathematical details of the qm KF algorithm are outlined in this paper along with the results from a challenging test bed simulation.

Sep 8, 2021

By Edgar Urbaez

Production scheduling is one of the most important factors affecting mine planning. A program -Mine Scheduler -that aids mining engineers with the setup of an optimum open pit production scheduling algorithm has been developed. A mathematical model for open pit scheduling that optimizes the Net Present Value of the cash flows was formulated. A simulated data is formulated as a Mixed Integer Linear Programming (MILP) problem. What's Best by Lindo Systems is used as the MILP solver in Microsoft Excel. The implementation of the algorithm focuses on problem setup, allowing users to easily evaluate, simplify, and develop the model that best fits their production scheduling.

Jan 1, 1999

By Pavel Vasak

The Laurentian University Virtual Reality Laboratory (VRL) has provided a unique platform for the development and testing of novel seismic and microseismic data processing and visualization technology. In collaboration with Vale?s Creighton Mine, the technology was implemented at the mine site and consists of a VRL system and site calibrated Seismic Excavation Hazard Map (SEHM) software. The SEHM was developed as a practical solution for the mine operator to identify areas of elevated, active rock mass damage processes caused by recent mining activity. This paper is a pictorial representation of the 3D stereoscopic demonstration of the Creighton Mine seismic data distribution and interpreted SEHM for the first quarter of 2009. A live demonstration is scheduled at the Laurentian University VRL as one of the conference field trips. The demonstration highlights the technology transfer of research concepts into a near-real-time excavation hazard system that utilizes the key aspects of virtual reality technology; the ability to integrate large datasets (geology, mine excavation, (seismic) monitoring data, production scheduling, stress model, etc.); the ability to manipulate and visualize large datasets in both space and in time (mining sequence); and the ability to review the datasets by a group of experts in an immersive (3D stereoscopic), collaborative environment to better understand the processes and context of the mining-induced seismicity and evaluate potential risks to the mining operation.

Oct 1, 2010

By M. Gonçalves Peixoto da Silva, E. Rodrigo Carvalho Souza Siqueira

Mining in narrow veins is commonly applied for precious metals, generally carried out to extract gold in underground mines, due to the ore occurrence on narrow veins, mainly up to 2-meter large. The current work presents the implementation of the methodology in a zinc mine located in the state of Minas Gerais in Brazil. The Vazante Mine through the years has always carried out mining on stopes with a thickness larger than 3,5 meters, but nowadays due to the need to reduce the waste planned in its blocks, as well as increase the useful life of mine, mining has been implemented in blocks that are less than two meters. Given this, the challenge is to be able to carry out blasts that does not exceed the operational dilution required and does not generate an impact on recovery, as working with extremely heterogeneous stopes. This study seeks to correlate the main characteristics of stopes and its relationship with the results obtained in the execution of those blasts. Also, it proposes an analysis between the empirical data, and existing theoretical references, creating ideal mining parameters, such as minimum thickness, maximum height, and optimum timing in the blast plan. One of the main challenges for carrying out this mining method is the control of operational dilution, generally pointed out as the biggest difficulty for companies that adopt this methodology, due to the thickness of those stopes, any displacement can make it unfeasible, thus the technical level on carrying out the drilling and loading of these blocks must be impeccable, an understanding of the structural geology of the site is also essential for dilution control. The outcome will be a set of ideal parameters and mining methodology to guarantee the success in execution of these blocks, thus bringing a financial benefit to the company.

Jan 21, 2025

By N. M. Stubina, P. J. Lind

Barrick Gold is in the process of building several new mines and implementing new processes at existing mines for which metallurgical technology is of key importance. The roles of the company's Strategic Technology Solutions team and the Barrick Technology Centre are discussed within the context of their responsibilities within Barrick's Operations Support group. The paper will present an overview of the development of the technology centre from the former Placer Dome Research Centre to its current form supporting strategic technology, capital projects, and operating sites. Novel approaches to research and development will be presented as well as an overview of some of the technologies developed from bench-scale to pilot-scale, and beyond.

Jan 1, 2011