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By Yong-ming Chen, Chao-bo Tang, Yun Li, Long-gang Ye, Sheng-hai Yang, Hao-tian Xue

In order to achieve high recovery of Cu and Co during cobalt-bearing copper sulphide ore smelting process, reducing agent (coke) and sulphidizing agent (pyrite) were added into molten smelter slag for reducing-sulphidizing smelting to product Cu-Co matte. Effects of reductive atmosphere, pyrite dosage, smelting temperature and smelting duration on Cu, Co, Fe distribution behaviours were investigated. The results show that the distributions of Cu and Co are mainly enriched in Cu-Co matte, and the distribution ratio, LCu and LCo, improve with increasing of coke amount or pyrite addition, whereas above 6 wt.% coke or 20 wt.% pyrite, Cu and Co tend to transfer from matte to cleaned slag. A properly high temperature(1300) and smelting duration(3h) are beneficial to the enhancement of the distribution ratio of valuable metals, and under the given set of conditions, LCu > LCo generally. However, an undesired high Fe contents in matte limit further increase of LCu and LCo.

Jan 1, 2015

By Yongqi Sun, Zuotai Zhang

Our study investigated the influence of P2O5 and B2O3 on the viscosity and crystallization behavior of Ti-bearing blast furnace (Ti-BF) slags for the purpose of Ti extraction. The investigation of the crystallization behaviors were carried out using a single hot thermocouple technique (SHTT) and the viscosity was obtained by rotating cylinder method. For the viscosity, the results showed that P2O5 substantially increased the slag viscosity. P2O5 is a network-forming oxide, which increased the degree of polymerization of slags and accordingly increased the slag viscosity. However, both of slag viscosity and apparent activation energy for viscous flow remarkably decreased with B2O3 addition. As a typical network forming oxide, B2O3 was introduced into the network and existed dominantly as 2-D structure, BO3 triangular, which caused a simpler structure and a decreasing slag viscosity. As for the crystallization behaviors of Ti-BF slags, both P2O5 and B2O3 enhanced the crystallization trend of rod-shape rutile and suppressed the crystallization trend of dendrite CaTiO3. Therefore the added P2O5 and B2O3 caused the primary phase change from CaTiO3 to rutile. Additionally, it was found that the rod-shape rutile showed a 1-D growth, whereas the dendrite CaTiO3 showed a 3-D growth style.

Jan 1, 2015

By Cong Wang, Siyang Long, Pengcheng Zhang, Haibin Zuo

The present study describes central segregation of the High-carbon steel billets of 150mm square and its heredity to the following hot-rolled wire rods, whose sizes are 10mm and 6.5mm in diameter separately. The relationship between center segregation of the billets and solute element distribution of rods, the mechanical properties and microstructure of rods were studied experimentally. The results show that segregation index of C is higher than that of Mn. With the increase of central segregation, the stability of the mechanical property of the rods becomes worse. The formation of carbide network and central martensite in the rolled products can be attributed to the heredity of the as-cast central segregation. The 6.5mm-diameter-rod has higher tensile strength than that of 10mm diameter which might be due to bigger reduction ratio. Thermo Mechanical Control Process (TMCP) should be used together with Billet Centersegregation- controlling (BCSC) to improve the overall properties of rolled products effectively.

Jan 1, 2016

By Wenjun Duan, Qingbo Yu, Qin Qin, Junxiang Liu

In the study, the coke-oven gas (COG)-steam reforming process using hot blast furnace slag (BFS) as the heat carrier is explored for producing hydrogen and recovering high-grade waste heat of hot BFS. The method of the Gibbs energy minimization approach through Lagrange multiplier is adopted in the thermodynamic analysis of reforming process. The simulation is carried out to study the operation pressure, temperature and steam to carbon ratio (S/C) based on the chemical equilibrium calculations. The optimal operation conditions are determined to improve the yield and fraction of hydrogen in the COG-steam reforming process. The results suggest that the preferential operation conditions for COG-steam reforming process to produce hydrogen are achieved at 600ºC, 1.5MPa and S/C (5.0). Due to the CaO and other melts in BFS, CH4, CO and CO2 in COG are converted and removed efficiently, especially CO2. The hydrogen fraction reaches to 86.7% and its production is about 1.22mol with 1mol of the COG.

Jan 1, 2016

By Bart Blanpain, Tom Peter Jones, Muxing Guo, Liugang Chen, Huayue Shi

Fayalite based slag is formed during the smelting process of secondary copper resources. It was found that with the presence of high ZnO, the slag became viscous, causing a slag tapping problem. In the present paper, the phase relations of the slag system ZnO-“FeO”-SiO2-Al2O3- CaO (ZnO = 0-12 wt%, Al2O3% = 0-15 wt%, CaO = 0-1.5 wt%, with iron saturation) at 1150 °C is studied by using quenching technique followed by phase identification and compositional analysis of equilibrated samples. The dependence of FeO and Al2O3 solubility in the liquid slag on the chemical composition of slag is characterized. Based on the experimental data, the solid fraction of the slag, which may considerably, influences the slag viscosity, at the tapping temperature can be reasonably estimated and, therefore an appropriate modification of the slag composition can be made.

Jan 1, 2016

By Deepu Philip, Pratik Agarwal, Ajay Kumar Shukla, Ishani Shukla, G Rajesh

Steel plants generally employ static BOF end point control models to arrive at a given temperature and chemistry at the end of blow. These end point models have now been supplemented with chaos control models to steer the blowing process in the right direction while the blow is in progress. Merely arriving at the correct end point temperature is however not adequate because in the subsequent stages as well the temperature variations can be large and unpredictable. The present paper deals with an integrated model to take into account the effect of all parameters affecting temperature and composition from tapping to the start of casting to minimize the use of LF or aluminum heating, and also minimize grade mixing. The application of lean operations strategy is explained in which the previous “Push System’ is changed to a “Pull System”, minimizing the use of ladle furnace or aluminum heating during steelmaking.

Jan 1, 2014

By Nobuaki Sato, Tetsuo Fukasawa, Akira Kirishima

To apply the fluoride volatility process for the treatment of fuel debris formed in the damaged nuclear reactors, study on the fluorination behavior of main constituents, such as fuel and cladding is essential. The mixture of uranium and zirconium oxides is formed under severe conditions such as high temperature and oxidizing atmospheres. In this paper, fluorination and volatilization behavior of uranium and zirconium oxides have been studied by TG-DTA method in the presence of fluorine. From the TG-DTA result of UO2 in F2 atmosphere, the weight gradually increased up to 7% at 350 oC followed by rapid weight decrease with exothermic peak showing the vaporization of uranium as UF6. ZrO2 showed similar fluorination behavior to that of UO2. However, fluorination of UO2-ZrO2 seemed to be suppressed with increasing ZrO2 amount. This may be caused by the formation of solid solution.

Jan 1, 2016

By Wetzeil N

High ambient temperatures combined with high surface humidity in the north of Australia and, in particular, the northern areas of the Northern Territory can make underground workplaces relatively inhospitable at certain times of the year. . Woodcutters' silver/lead/zinc mine, situated some 80 km south of Darwin, would be the most northerly underground operation of any significance in Australia. As such, during the build up to the wet season, it has a particular problem of ventilating a deep underground mine with already high dry and wet bulb temperatures at the surface. The Mine Management Act and Regulations mention only that workplaces shall be 'in a fit state for a person to work in or occupy'. Woodcutters therefore set in progress a Heat Stress Program to endeavour to set standards which would be more measurable and justifiable. The aim of the program was to compile a record of ambient atmospheric conditions in the working areas such that areas and/or work activities generating high ambient temperatures and humidities could be identified, quantified and qualified. Once the analysis stage of this program was completed, Woodcutters compiled a set of recommendations for the continued monitoring for, and control of, heat stress conditions to ensure that no underground employee was placed at risk from 'heat stress'. These recommendations are discussed in this paper.

Jan 1, 1994

By Cocks T

The 15-year long debate between the industry, Government and Aboriginal people about the rights and wrongs of Land Rights, the right of Aboriginal people to control development on their land and the relationship between the parties, has been long and often bitter. It has so far been a war of words and often the truth has been the first casualty. This paper looks at the debate and presents the perspective of Aboriginal people, as well as looking at how the industry and Aboriginal people can work together for everyone's benefit. It addresses such matters as: ò why Aboriginal people believe they have the right to control development on their land; ò the perception that Aboriginal people are anti-development; ò the perception that Aboriginal land is 'locked-up'; and ò how companies can negotiate with Aboriginal people.

Jan 1, 1994

By Joseph M. Driscoll

After 30 years of successfully mining gold, Newmont Gold has temporarily ceased production from the original Carlin Pit. In late 1993, the Carlin East decline was driven and an extensive underground exploration program was started. Today, Newmont Gold produces refractory ore from the Carlin East Underground at the rate of 864 t/d (950 stpd). Annual production is more than 3.1 t (100,000 02). More than 70 underground miners will be employed during Carlin East's estimated six-year mine life. About 70% of the ore at Carlin East is mined by mechanized longhole stoping with delayed, cemented backfill. The remaining ore is mined by underhand drift and cemented fill methods.

Jan 1, 1997

By D. E. Ranta, William B. Ryan, Ronald W. May

The Lower Cretaceous McMurray Formation in northern Alberta contains bituminous sands interbedded with other sediments which form the reject encountered during mining operations. Grade prediction is based on a combination of geological interpretation, computer modelling and past mining experience. In addition to estimates for ore, an accurate estimate of "waste" or "reject," are required for Mine Planning. This study investigates the ability of point-kriging using geostatistics, to augment the existing data base of drill-holes in a study area on Syncrude's leases. This approach enables the assessment of potential "worst" case - "best" case scenarios within the context of Mine Planning.

Jan 1, 1992

By JIAQI JIN, Joe Milbourne, Maoming Fan

Gold is very important to support the financial system, and to be used in industries of the jewelry, high-tech fields such as electronics and aerospace, etc. Gold is mainly extracted from three types of ores: primary ore (vein gold), placer (alluvial gold) and associated ore. Cyanide was widely used in gold ore flotation to depress gangue minerals and leaching/cyanidation. The process of extracting gold from gold ore, its separation and flotation concentrate, specifically through a technique called cyanidation or cyanide leaching. This method, which has been dominant since the 1970s, utilizes a dilute solution of cyanide to dissolve gold from the ore. While effective, the use of cyanide raises environmental and safety concerns due to its high toxicity. Cyanide spills can have severe environmental consequences. This has led to the exploration of alternative, environmentally friendly reagents. This paper discusses processing results using the alternative flotation depressants such as sodium sulfite (Na2SO3), etc. to produce a goldrich flotation concentrate for sale to a smelter or as feed to an alternative leaching agent. and methods to extract gold from ore without relying on cyanide.

Feb 22, 2026

By Christopher Newman, Andrew Minckley

With underground stone operations developing in deeper and more geologically complex conditions, accurate pillar stability analysis becomes for the evaluation of engineering design. This paper provides engineering-based recommendations for applying LaModel to evaluate multiple-level room-and-pillar stone mines in both shallow and deep cover. It provides practical guidance on model calibration using field observations, selection of input parameters, and interpretation of results to inform design and operational decisions. The analysis demonstrates LaModel’s effectiveness in simulating pillar load transfer, stress redistribution, and failure mechanisms in complex mining geometries where empirical methods may be inadequate.

Feb 22, 2026

By Qingyun Huang, Junyi Xiang, Xuewei Lv, Chenguang Bai

The extraction of vanadium from mechanically activated converter slag was studied in dilute sulfuric acid solution. The effects of roasting and leaching parameters were investigated. The results show that Ca/V mole ratio, roasting temperature, leaching temperature, liquid-solid ratio, and particle size all have significant effects on vanadium leaching efficiency from calcification-roasted converter slag.

Mar 1, 2017

By Yuanbo Zhang, Yingming Chen, Zijian Su, Bingbing Liu, Guanghui Li, Tao Jiang

High calcium type tin, iron-bearing tailing is recognized as one of typically complex iron ore resources in China. A process of magnetizing roasting process followed by magnetic separation was used to utilize the tailings in our previous paper. Under the optimal conditions, qualified magnetic concentrates were obtained and could be used for direct reduced iron production. In this study, the phase transformation of these tailings during the magnetizing roasting process was investigated. And the reaction behavior between calcium oxide and iron oxide was revealed by using XRD, TG-DSC, VSM, etc. The results indicated that calcium ferrite was easily formed under CO–CO2 atmosphere, which has an unfavorable effect on the separation of iron and tin oxides from the tailings.

Mar 1, 2017

By Chengyi Ding, Yangyang Xie, Xuewei Lv, Senwei Xuan, Chenguang Bai, Kai Tang, Gang Li

Dicalcium ferrite (2CaOFe2O3, C2F) is one of the most significant bonding phase of fluxed sinters. Reduction of C2F was investigated via thermal kinetics analysis. The isothermal reduction behavior of C2F by 30% H2 and 70% N2 at 1123 K (850 °C), 1173 K (900 °C), and 1223 K (950 °C) were discussed by thermogravimetric analysis in this paper. The results revealed that the C2F reduction was typical one-step reaction. The apparent activation energy of the C2F reduction was 27.40 kJ/mol. The rate-determining steps of the C2F reduction were the first inner gas diffusion, then the inner gas diffusion and interface chemical reaction mixed controlling. The ln-ln analysis implied that the C2F reduction was described by the Avrami–Erofeev (A-E) equation, thus appeared as a 2D A-E equation kinetics reaction.

Mar 1, 2018

By Fuming Wang, Xi Chen, Shuai Liu, Changrong Li, Dan Wu, Yaxu Zheng

The effects of B content and austenitizing temperature on hardenability and toughness of Cr–Mo alloy steel have been studied. The results show that the hardenability is deteriorated with increasing B content and austenitizing temperature. With increasing temperature, more and more B containing particles were dissolved in austenite and increase the amount of B atoms segregating at grain boundaries. Moreover, the coarsening grains reduce area of grain boundaries and also increase the amount of B atoms at unit grain boundary, excessive B atoms segregating at grain boundaries promotes precipitation of M2B, which accelerates ferrite nucleation and reduces hardenability. The main elements in M2B phase are Fe, Cr, Mo and B. The B atoms segregating at grain boundaries during austenitizing promote precipitation of M2B during tempering which deteriorate toughness significantly.

Mar 1, 2018

By R. Bissonette, C. Sunderman, R. Jacksha

The ability of wireless systems—e.g., voice communication, proximity detection, tele-remote operation, telemetry, etc.—to function satisfactorily (coexist) in the presence of other wireless systems is critical to the safety and health of mine workers. The failure of wireless systems to coexist could result in the delay, corruption, or outright loss, of critical data, voice, or video information. However, no mining-sector-specific regulations, standards, or guidelines exist to ensure the safe coexistence of wireless systems. This paper introduces the concept of wireless coexistence, implications in the mining industry, and the National Institute for Occupational Safety and Health’s (NIOSH’s) research approach to develop guidelines and recommendations to ensure safe wireless coexistence.

Feb 1, 2023

By H. D. Lelono, M. Walden, G. Johnson

3D modelling can be used throughout the mine lifecycle and has proven to be a powerful tool for consultants and mining companies. One of the most significant benefits of 3D models is their ability to enhance collaboration, communication, and understanding between the mine owner, design engineers, and other relevant stakeholders that have a shared interest in responsible mining and site management. Tailings and mine waste management is an interdisciplinary effort that requires effective coordination and communication between a wide range of consultants, operators, and stakeholders alike. The increased emphasis on Environmental, Social, and Corporate Governance (ESG) highlights the importance for mine operators to engage and communicate with all parties involved in the planning, permitting, operation, and closure of mine sites. 3D models are valuable tools that can be used for development of geotechnical conceptual models, allowing for improved design and monitoring of Tailings Storage Facilities (TSFs). A clear conceptual understanding of a TSFs subsurface geology and foundation characterization is essential for proper tailings management, design, and planning. Visualization with 3D modelling can simplify the interpretation of the, oftentimes intricate, mine sight subsurface settings and allows for quick and effective geotechnical conceptualization. 3D models can be used to identify data gaps, optimize field investigations, and streamline the development of numerical stability or groundwater models. They can help communicate the complex nature of subsurface and TSF interactions in a clear, concise, and accurate manner to both technical and nontechnical stakeholders. This paper discusses some of the benefits of 3D modelling in relation to geotechnical analysis for tailings management and provides methodologies for how to improve upon some methodologies that are considered industry standards.

Feb 1, 2023

By Rennie B. Kaunda, Robert J. Sterrett

Some people in the mining-engineering field mistakenly believe that mine-water management primarily revolves around the treatment of mine waters that fail to meet applicable water-quality standards. While water-quality control is undoubtedly important, it represents only a fraction of what constitutes comprehensive site-wide, minewater management. A more holistic perspective recognizes that it also involves mine dewatering to maintain safe and workable conditions, securing sufficient water supply for operations, strategically handling surface water within and surrounding the openpit to prevent issues like flooding, developing robust post-closure plans to mitigate long-term environmental effects, and proactively minimizing any adverse impacts on local communities and ecosystems. This article provides a brief overview of topics that fall within the concepts of mine-water management. The focus is on openpit mines, as they are generally larger than underground mines. The management of mine water is highly dependent on local and regional climate such as tropical, desert or temperate climate. Each climatic setting has its own unique challenges, but there are also commonalities.

Jun 1, 2025