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By R. W. Ruddle

The advent of new methods of roasting, “flash roasting and fluidisation”, which are now under development, combined with the use of oxygen-enriched air, may markedly increase the SO2 content of roaster smokes. Skogmo suggests that the production of smokes containing as much as 50 per cent SO2 should be feasible. The use of flash smelting processes may well enable a similar increase in the SO2 content of smelter smokes to be made. In this event the recovery of sulphur would be greatly cheapened and the process might well be much more economic, even if allowance is made for the cost of generating the oxygen

Jan 1, 1953

By TTE-Europe GmbH

A few years ago, the term Track & Trace for explosives was only known in Europe and Brazil at most; the introduction of this technology is experiencing an undreamt-of boom worldwide. More and more countries are enacting legislation to introduce Track & Trace of explosives and follow Europe and Brazil on this path. At present, the world's leading manufacturers are already using such solutions, are in the process of implementing them, or are in the planning process. However, based on the experience gained in Europe, there are outstanding challenges for all manufacturers. These are questions of compliance, logistics, distribution, and, of course, especially, the necessary adaptation of the production environment. However, this development involves considerable effort on the part of the manufacturers. New devices for marking the explosives and digitally recording the data are integrated into the production process. This should be done as cost-effectively as possible, without restricting production capacity and speed, and with as few process changes as possible. This paper uses real-life customer experiences examples to explain paths from project design to real implementation. Lessons learned from the experience of European explosives manufacturers are presented, missteps are described, and solutions are identified. Individual steps along this path are explained, and solutions are told to avoid pitfalls and bottlenecks. Finally, it refers to the risk analysis and concrete examples in implementing the planning into production. Methods of marking various explosives are shown, and the use of Track & Trace to solve logistics tasks in picking and shipping explosives, including the data exchange with ERP (Enterprise Resource Planning) systems.

Jan 26, 2026

By G Richmond, J R. Glen

Western Metals Mt Gordon Operation is a copper mine and processing plant situated 120 kilometres north of Mt Isa. The unique Mt Gordon copper process utilises a whole of ore acid/ferric pressure leach to produce copper cathode from the Esperanza massive sulfide copper orebody. Esperanza ore contains chalcocite, covellite and minor chalcopyrite hosted in a massive pyrite matrix. These ore stocks will be depleted in late 2003. Recently the process circuit has been upgraded to allow the treatment of lower grade Mammoth ores. These include the installation of a ball mill to complement the existing SAG mill, a single stage rougher flotation circuit and a tailings thickener. The leach bleed neutralisation plant was also upgraded at this time. Commissioning of these new circuits occurred in March 2003 and involved all the challenges of ensuring current production levels were successfully maintained while new process steps were incorporated into the whole circuit. This paper explains the background flow sheet of the patented Mt Gordon process and the reasoning behind the enhancements required for an already successful copper leaching circuit. Included are discussion of the influences of the new ores on individual process components such as comminution, leach chemistry and solid/liquid separation. Longer term ore processing options are also discussed.

Jan 1, 2003

By D Jeffery, R Whittering, G Lane

Most aspects of process design are best addressed via bench scale or pilot plant scale test work. However, as experience is gained, fundamental or indicative data can provide more than adequate information to manage the risk associated with some process aspects of concentrator design.Historical precedence exists where minimal design test work has resulted in successful projects. On many occasions benchmarking, sometimes supported by fundamental data such as mineralogy, has been used to successfully develop effective process plant outcomes. Of course, this style of approach is most common with æfast trackÆ projects and often comes with the usual surprises that result from inadequate geometallurgy to define the project cash flow.This paper explores the risks and opportunities associated with the various facets of process development and design for a base metals concentrator. The paper is intended to provide guidance to project managers rather than address the technical aspects of process engineering.CITATION:Lane, G, Whittering, R and Jeffery, D, 2012. Benchmarking versus test work - How should you manage process risk?, in Proceedings Project Evaluation 2012 , pp 49-52 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 24, 2012

By F. W. SUTTER

IN order to have ore available on the completion of the beneficiation plant at Clifton and to provide for continuous production while underground development was carried out, it was decided to develop an open-pit through the crest of a long hill in which the ore outcropped, using 40-ft. vertical benches.

Jan 1, 1943

By R. Ratnagiri, B. Minaie

"In order to expeditiously produce defect-free metallic components in materials processing applications, the relationship between the process parameters and the product properties needs to be well understood while minimizing the production engineering iterations. To achieve this goal, a realistic mathematical formulation of the process should be carried out and an appropriate numerical modeling of various phenomena occurring in such process should be implemented. The materials processing of transforming the molten material into a finished metallic component involves fluid flow and solidification/melting. In the present paper, a finite element based analysis of the fluid flow ·and solidification/melting phenomena in cavities is presented and the various issues in modeling these phenomena are discussed. These transport phenomena play an important role in determining the final characteristics and material properties of the part by affecting the formation of defects and microstructure. A realistic numerical modeling of these phenomena can significantly reduce the rejection rates during the process and can increase the quality of the final product.IntroductionDuring the intelligent materials processing of various metallic components, it is often required to have a thorough knowledge of the behavior of the transport phenomena involved in this process. This is due in large to the coupling that exists between the transport phenomena and the final material properties of the components produced during materials processing. This interrelationship demands that the pertinent transport phenomena in the form of fluid flow and solidification/melting be studied and predicted accurately. In many materials processing applications, the fluid flow is in the form of either a forced convection free surface flow intended to fill a cavity or a natural convection flow resulting from the gravity when the cavity is filled. In either case, the phase change in the form of solidification/melting is also involved in order to complete the process. However, the thermal history during this phase change has a direct impact on the material properties of the final part and the possible defect formation that may be involved. This thermal history itself is dependent on the nature of the fluid flow during the earlier stages of the process. As such, there is a coupling between the fluid flow, phase change, microstructure, and defect formation in the resulting component. It is therefore necessary to analyze these phenomena in order to find optimum methods to produce good quality parts by minimizing the defects that may be generated. Such an analysis can result in the development of appropriate numerical models for the process that can facilitate the economical and timely manufacturing of various components with high consistency. The present paper discusses the issues related to the transport phenomena encountered during materials processing of components engineered largely by using various combination of convective fluid flow and solidification/melting in cavities."

Jan 1, 1994

By Donald Leroux, Simon Gariépy, Luc Lachance

"Quantitative information about the quality of metal balance results is often overlooked when making important plant production planning decisions. Not only is this common omission made in a context where many measurements taken in and around mineral processing plants carry significant errors, but it also conflicts with the AMIRA P754 Code of Practice for Metal Accounting. The fact that metal balances are typically published without any indication of data quality may give the wrong impression that the measurements are unquestionably accurate. While it is true that statistical data reconciliation can improve the confidence intervals of redundant variables, there is no data processing technique that brings them down to zero at a finite cost. In this paper, we review the entire data flow, starting from field instruments to metal accounting-based decision-making to show how measurement errors are transmuted into business risks associated with production planning. Necessary conditions for first exposing then quantifying such business risks are stated. Pitfalls to be avoided are also discussed. Finally, a simplified risk assessment and management procedure which considers the quality of metal balance results are applied to a polymetallic mineral processing plant. INTRODUCTION Each and every mineral processing plant has production reporting obligations. In this paper, we are concerned with metal accounting reports (Morrison, 2008) where saleable metal flows and inventories are estimated and published. These metal accounting reports are delivered to a variety of stakeholders who use them for internal management purposes (day-to-day plant production planning, plant operation optimisation, capital spending, etc.) as well as for external management (royalty settlements, tolling agreements, etc.). Hence, there should be no doubt that spotless metal accounting is instrumental to high-quality corporate governance (Gaylard et al., 2014) of mining and metallurgical companies. To this extent, one would have expected industry-endorsed standards to have emerged a long time ago. However, the lack of an accepted set of standard procedures for metallurgical accounting was explicitly recognized as an industry-wide problem only in August 2001 during an SAIMM workshop held in Cape Town, South Africa. Discussions that followed this workshop led to the initiation of the AMIRA Project P754, “Metal Accounting and Reconciliation”, in 2003."

Jan 1, 2015

By J. Winters, L. Vos, C. Canoo

Committed to a sustainable development of zinc applications, Union Miniere is investigating processes for the minimisation of waste and residues originating from the classic hydrometallurgical zinc process. In that context, Union Miniere has developed a method for the cold inertisation and solidification of goethite, the Graveliet® process. The result is a hard and inert gravel that can be used in the building industry. During the past two years, a pilot plant for the production of Graveliet® has been built and operated. In the present paper, the Graveliet® process and the pilot plant are described after which the properties of the produced gravel are discussed, from both a mechanical and an environmental point-of-view. Graveliet fulfils the criteria for use as a secondary building material. The GravelietJ process is a viable technology to avoid stockpiling of goethite residues and it thus assures the long-term development of the hydrometallurgical zinc process.

Jan 1, 2000

By ZHONGLING ZHAO, WANTING SONG, GUOZHONG LIU, LEIXIN SHI, ZUI WANG, YUANYUAN LIU, KE GAO, DONGHONG JIANG, WANG LUO, PEICHAO LU, Jianwei Cheng, WANCHENG ZHENG, Gang Zhao, YUNGANG WANG, JIANBING ZHAO

Coal spontaneous combustion is one of the disasters occurring in underground coal mines. As a typical case, the spontaneous combustion of broken coal left in the longwall gobs often happen which could greatly interrupt the normal mining production. Such concealed thermal event is featured as rapid development and difficulty in locating “hot” spots. If such spontaneous combustion fails to be timely prevented and controlled, a large amount of toxic gases (mainly CO) and smoke could flow and diffuse in the underground working sections, which could present safety hazards for coal miners. In this paper, based on an coal spontaneous combustion event happened in a Chinese gassy mine, the fire ratios derived from the gas composition data obtained through the tube bundle mine atmospheric monitoring system are used in determining the fire status. A comprehensive and collaborative fire extinguishing effort including inert gas injection, underground pressure balance, and sealing enhancement are made to control the fire progress. Simultaneously, the effects of such works to control the spontaneous combustion event have also been quantified using the fire ratios to justify again. Finally, the danger of coal spontaneous combustion in gob is eliminated, and the longwall panel is successfully re-opened for normal production.

May 6, 2021

By D. Hanekom

Over the past couple of years, Anglo Platinum has made extensive use of technology within the core disciplines (geology, evaluation, survey, and planning) that collectively form part of mineral resource management (MRM). While these technologies were primarily developed to enable geology, evaluation, survey, and planning to carry out their daily tasks, with the main objective of supporting the mine?s production effort, they have also enhanced the disciplines? ability to produce the required outputs within the annual business planning cycle. Anglo Platinum has developed a very comprehensive business planning process, and these technologies play a vital role in enabling both the quality and quantity of inputs into the process, and also the value-add of the final product. This prompted a question regarding the practical application of the CADSMine software. If we changed our thinking in how we applied the software, would it be possible to further improve on the time taken to deliver a business plan? In changing the current planning approach, would we be able to further simplify the process? Is there a way to reduce the data generated in order to enhance the time taken to do reporting, as the CADSMine software is totally network dependent? Less data should equal faster reporting. This paper focuses on the practical application of the CADSMine software, and demonstrates the value-add to the business planning process that can be gained if the mine design methodology is changed from individual panels to bigger blocks representing a raise line.

Jan 1, 2012

By K. M. Uderstadt, G. C. Howell, L. de Villiers

This paper highlights the advantages of developing tailings storage facility-specific water balances. A case study illustrates how such focused analysis provides clearer insights into water storage and release, supporting improved conservation, regulatory compliance, and enhanced stability of tailings storage facilities. A robust water balance informed by up-to-date hydraulic data is essential for long term management. It is proposed that tailings storage facility-specific water balances should be regarded as standard practice in mining.

Apr 8, 2026

By L Salvestro

Ventilation on demand (VOD) has been demonstrated to significantly reduce operating costs for ventilation fans, by reducing fan output to meet demand. The most effective method for reducing operating costs is to use variable speed drives to adjust the speed of ventilation fans as required – this achieves significantly larger power savings that damper or vane control alone.However, this mode of control will significantly increase the number of speed cycles the ventilation fans will experience. Fabricated impellers have a limited number of start stop cycles based on the materials and method of construction, and the operating stresses due to centrifugal forces. This means that fans experiencing constant or regular speed changes will experience a reduced fatiguelife compared with fans that are run at constant speed.The fatigue life of fans operated under various speeds using VOD is difficult to predict, as it is dependent on the magnitude of speed changes, and the frequency, which will be varied to meet demand. It is important to be able to estimate remaining fatigue life to assist in maintenance planning and avoid unplanned maintenance activities.This paper will review extensive VOD data on fan operating conditions from two primary mine ventilation fans. This paper will demonstrate how this data can be used to calculate accumulated fatigue and predict the remaining fatigue life, and how this compares with fixed speed or non-VOD controlled fans.The increased maintenance costs for the impellers will also be estimated, and compared to the operating cost savings using VOD, to determine if the savings outweigh the additional maintenance costs.

Oct 12, 2022

By C. E. Saxon, F. E. Cash

"Adequate lighting for all mining operations would unquestionably tend to promote both safety and efficiency; this would be true not only for men but also for the animals that man impresses into service in mines. The Markeeta Coal Co. and the Alabama Fuel & Iron Co. both operating mines in Alabama, have found that equipping mine mules with portable electric lights is more efficient, much more humane, and far more safe for both men and animals then the more or less usual method of forcing the animal to do its work essentially in darkness.This report is intended to give the mining industry data, that will aid in trying to bring about safe and efficient operation of mines.The authors desire to thank Charles F. DeBardeleben, president, Fred R. Bell, general manager, Hewett Smith, C. H. Shepherd, and R. A. Sensing, superintendents for the Alabama Fuel & Iron Co.; and Charles F. DeBardeleben, Jr., president, and H. M. House, superintendent for the Markeeta Coal Co., for their cooperation in furnishing the data for this paper.The eight mines operated by the Alabama Fuel & Iron Co. and one operated by the Markeeta Coal Co. in Jefferson and St. Clair Counties, Ala., are the only mines in Alabama where mules are provided with portable electric lights, and there are few if any mines in other States in which this system is in use.These two companies are convinced that equipping all mine mules with good lights decreases underground haulage cost by animals by prolonging the useful life of the animals, increasing their efficiency, lessening haulage wrecks and delays on haulage, and increasing production. Last but not least of the advantages would be the more humane treatment of the animals.The nine mines are developed by slopes along the dip of the coal bed, with double-room entries on 200- to 300-foot centers turned right and left off the slopes and with approximately 1 per cent grade in favor of the loads. Rooms are driven up or diagonally up the pitch from these entries.A surface hoist delivers the empties from the surface to the entry sidetracks at the slope and pulls the loads to the surface. From these sidetracks, mules pull one to four wooden cars, each of which holds 1-1/2 to 2-1/2 tons of coal, deliver the empties to the rooms and entry faces, and pull the loads to the slope sidetracks. The mule haul varies from 100 to 3,000 feet; there are no locomotives or trolley wires in any of these nine mines, seven of which are rated as gassy and two as nongassy by the Alabama state Mining Department."

May 1, 1933

By Chonghun Han, Tae-Hwa Choi, Young-Hwan Chu

"A statistical optimization method is proposed to maintain stable operation in a blast furnace with stave coolers. The objective of this study is to find the operating condition which maximizes productivity as well as minimizes the heat load on the stave coolers. In this method, we first analyzed historical data and calculated the heat flux of stave coolers and the burden distribution by mathematical models. In this approach, we determined the variables to optimize and manipulated variables to adjust these response variables. Next, we collected the necessary data for the data variables after preprocessing such as removal of noise and outlier. Finally, we constructed empirical models describing the patterns of response variables in terms of manipulated variables by partial least squares regression method, and then these models were used as objective functions for entire optimization problem. By using appropriate optimization algorithm, we determined the compromised optimum operating condition considering all response variables from the past operating conditions.IntroductionBlast furnace operation which is accompanied by complex physical and chemical phenomena is an essential process for steel industry. In this process, iron ore which is charged into the blast furnace from the top goes downward. It is reduced to iron by CO gas and is melted by the heat of combustion of coke and pulverized coal. The pig iron is tapped at the bottom in liquid phase after removing the slag, which floats on the pig iron.The cooling equipment of the blast furnace wall is changed from the plate type to the stave cooler recently. In order to cool the shell uniformly and eliminate shell spray cooling, Pohang No.2 blast furnace of POSCO (Pohang Iron & Steel Company) was equipped with 11 rows of stave coolers. These staves are only 350mm-thick including the 170 mm-deep refractory on the hot face."

Jan 1, 2001

By A. Oleynik

The paper presents the modeling and simulation experience in field of research into the mineral row material separation. Features of the subject domain generate a need of different approaches using for modeling and simulation. The general scheme of separation modeling process and some examples of developed simulators are presented. Due to different features and standards of knowledge, different formal models should be used to describe and analyze separation processes in the frame of general scheme. The main types of simulators are modeling tools based on statistical, analytical or expert (logical) methods. Advantages and disadvantages of each method above are mentioned in the paper. Based on the studies in the field considered, an aggregated mathematical model of a separation process has been generated. The aggregated model is presented by two combined equations. The actual apparatus model is formed by substitution of the particular functional expressions of the forces acting in the apparatus into the aggregated model. The developed simulation tools are based on integration of limited experimental data and on ex-pert knowledge available on separation processes. Simulation does not allow producing an optimal, in terms of mathematics, solution. But it gives an opportunity to produce and compare quite adequate solution variants in real time. The results obtained are the theoretical and methodological base for integrated information technologies to support studies in the field of mineral processing.

Jan 1, 2014

By Jesús E. Gómez

Verification and production testing of soil nails requires debonding the upper section of the soil nail to isolate the portion of the soil nail intended for testing within a specific ground type. In pre-drilled soil nails, debonding can be accomplished relatively easily because the bar can be fitted with a debonding sheath before its installation. However, debonding of hollow core bar soil nails requires special procedures to achieve the intended result. This paper is a summary of the Federal Highway Administration (FHWA) Hollow Bar Soil Nail (HBSN) Test Program, which is described in detail in FHWA-CFL/TD-10-001. The program was developed to establish a suitable debonding procedure to test hollow core bars in soil nailing applications, and to initiate a database on typical bond values of HBSNs. The investigation showed that it is possible to debond hollow core bars for testing. It was also found that hollow core bars installed in granular soils may present ultimate bond values that are significantly higher than those typically used for design of conventional pre-drilled soil nails.

Jan 1, 2011

By Ignazio Carbone

"During the design of a typical modern subway, engineering aspects prevail since underground structures remain hidden to most humans. Aligning the advanced architectural concepts with the engineering requirements of the Naples Metro Line 1 (Italy) called for a thorough rethinking of the design process so that the engineering could be kept aligned with the architecture, integrating seamlessly the two with the construction methods, standards and technology.The preliminary design process consisted of three major phases: •,geotechnical and geological issues, preselection of construction methods; •,functional scenario based on engineering and construction requirements; •,review and merging of the architectural concept with the functional and engineering aspects. The last phase proved the most demanding one, matching the first outline sketches with the applicable construction methods. This required continuous alignment of approaches, eventually leading to the design consistent with the original architectural vision, yet fully compliant with the engineering and construction framework. At the beginning general information on Line 1 will be provided, followed by some main features of the construction work along the Dante – Garibaldi section both for the tunnel and the stations. At the end, the selected methodology and the related consequences on the functional, technical and architectural design will be outlined.City of Naples current municipal transportation plan envisages a circle ring line for the metro line M1. Actually it’s open to public the segment Piscinola – Dante – Garibaldi run by AMM, municipal company. This ring segment has been built by Metropolitana di Napoli, while Napoli Metro Engineering (company belonging to MMspa Group) is in charge for the planning of entire system and construction management. Line 1 connects Piscinola-Secondigliano northern periphery to Vomero shopping neighborhood, downtown and Central Railway Station."

Jan 1, 2016

By James R. Myers

A source of clean gas containing sulfur dioxide and sufficient oxygen for conversion to sulfur trioxide is essential to the production of sulfuric acid. SO2 containing gases obtained from roasting sulfide ores are heavily contaminated with inorganic dust and volatile impurities. If not removed, these contaminants will reduce product acid quality, foul the catalyst beds and mist eliminators, and accelerate equipment corrosion. This paper reviews conventional gas cleaning systems for metallurgical acid plants, followed by a discussion of modern systems utilizing DynaWave Scrubber technology. This technology is based on a unique approach togas scrubbing that can concurrently accomplish several gas cleaning/processing tasks. Scrubbing liquid is injected into the gas stream to create a "Froth Zone". This is a region of extreme turbulence, with a very high rate of liquid surface renewal. It efficiently removes both particulate matter and gas contaminants, and is also a cost effective quenching device for gases as hot as 1250 o C.

Jan 1, 1992

By Lei Zhang, Shining Chen, Lina Wang, Pu Liu, Benquan Fu, Jiannyang Hwang

A PFS(polymeric ferric sulfate) coagulation-photocatalytic oxidation technology was used for advanced treatment of coking wastewater from secondary biological treatment. Effects of some key factors on TOC removal rate were investigated, and the results were compared with those of the common photocatalytic oxidation technology under the operating parameters of the photocatalytic oxidation defined. Single factor experimental results showed that TOC removal rate could reach 81%, when optimal operating conditions were as follows: TiO2 loading: 4.0g/L, irradiation time: 4h, initial pH is 5.1and PFS dosage:700mg/L. PFS coagulation and photocatalytic oxidation have synergistic effect, which is meaningful for highly efficient treatment of coking wastewater

Jan 1, 2015

By B. Das

Most coals are susceptible to spontaneous heating which in turn creates problem to mining, storage and transportation of coal. It is impossible in actual practice o eliminate spontaneous heating but spontaneous combustion can effecively be controlled through a clear understanding of its mechanism and the factors affecting it. There are altogether six stages in the process of spontaneous combustion. This includes the water adsorption stage and six oxidation stages: chemi-sorption (upto 70°C), decomposition of peroxygens (70°C-150°C), oxy-coal formation (150°C-230°C), combustion initiation (230°C) and active combustion (> 230°C). Heat is produced in all these stages. On the other hand heat is also dissipated so that some equilibrium temperature is reached. If this temperature exceeds a certain critical value (generally about 70°C), coal oxidation may advance to spontaneous combustion. The major factors influencing spontaneous combustion of coal are: coal rank, maceral composition,, water, mineral matter, joints and fissures, seam depth and thickness, mine Layout, method of ventilation, etc. Susceptibility is high for low rank coals and generally decreases with increase in rank. Of the macerals, the exinites are generally most susceptible, the inertinites least and the vitrinites somewhere in between. Water plays a major role on the spontaneous heating of coal, assisting in someways and inhibiting in other. Unrecovered coal in the gob (generally in thick seams) is a major source of fire hazards and this is specially important in shallow mine. Proper design of mine ventilation system can substantially reduce the risk of mine fire. Panel layout and load transfer can affect the development of induced cracks which in turn influence spontaneous heating. Finally, the difference between the spontaneous heating of coal in a seam and that in storage or transportation is mainly due to the change in moistured content, air circulation through the coal and coal fragmentation. These aspects have been analyzed in this paper with a view o reducing the risk of spontaneous combustion.

Jan 1, 1986