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By E. Godin, M. Rigaud, S. C. Panigrahy, I. Malinsky

"RésuméDes boulettes de concentres d'hématite spéculaire à basse silice ont été produites en substituant la bentonite par de la tourbe, adéquatement traitée, additionnée d'une faible quantile de soude caustique durant le boulettage. La réductibilité de telles boulettes et leur gonflement pendant la réduction ont été évacues, en utilisant quatre mélanges gazeux différents, formes de H2 - CO - N2.L'influence du pouvoir réducteur du gaz utilise, sur le gonflement des boulettes, à été mis en évidence. Quelles que soient ces conditions réductrices, les propriétés mesurées sur les boulettes liées a la tourbe sont comparables aux propriétés obtenues avec des boulettes traditionnelles liées à la bentonite.ABSTRACTAdditions of peat moss and small quantities of NaOH during balling of low silica specular hematite concentrates have eliminated the need to use bentonite as a binder. The reducibility and swelling of such pellets have been evaluated using four different gas mixtures, consisting of H2 - CO -N2. The influence of the reducing power of the gases, on the swelling behaviour of pellets has been documented. Under the different reducing conditions, this new type of pellets exhibit properties similar to the ones obtained using bentonite."

Jan 1, 1987

By P Kittler

In the spectrum of mining-related disciplines, geometallurgy sits between resource geology and metallurgical engineering. Unlike its neighbours, it is a relatively young discipline and its concepts, procedures and techniques are still evolving. Relevant geometallurgical issues differ from one deposit to the next so there is no single template that can be used in all situations, meaning that geometallurgy programs are nearly always customised and tailored to the deposit and the situation.Over time, a number of key mistakes are seen to emerge regularly. The eventual impact of these mistakes can vary from suboptimal performance of mine and plant to complete failure of the operation. For instance, poor characterisation of ore lithologies and their spatial distribution can have negative impacts on processing plant throughput. However, when combined with failure to identify critical blending constraints it can result in a totally inoperable plant.A number of common mistakes committed during geometallurgical programs are discussed and some preferred alternative approaches are suggested

Sep 5, 2011

By C J. Unger, T Baumgartl, C J. Bond, P Sabourenkov, V C. Glenn

Social licence to mine is influenced by society’s perception of the mining sector’s ability to effectively rehabilitate mined land and for governments to appropriately regulate that process for the broader community benefit. In Queensland, Australia, many mine rehabilitation personnel working for active coalmines, as either staff, consultants or contractors, belong to the Central Queensland Mine Rehabilitation Group (CQMRG). The CQMRG was established 23 years ago with the aim of sharing informal knowledge related to practical aspects of rehabilitation in order to leave as positive a legacy as possible from mined land. This voluntary group of professionals also includes members from regulatory agencies and civil society. Within the dynamic regional mining environment, mine rehabilitation professionals benefit from sharing their informal knowledge.CQMRG is currently a group in transition. Mining boom and downturn cycles have exacerbated the loss of accumulated knowledge in the core CQMRG membership due to rapid changes in personnel at mines in the region. Additionally, some of the most experienced CQMRG-affiliated rehabilitation practitioners are approaching the end of their careers and want their valuable and less formal knowledge retained. This paper discusses the development of a research project that emerged in response to the anticipated loss of several decades’ worth of valuable knowledge as rehabilitation practitioners in CQMRG left the region or the workforce.CITATION:Unger, C J, Bond, C J, Baumgartl, T, Glenn, V C and Sabourenkov, P, 2016. ‘MRC-wiki’ – a mine rehabilitation and closure knowledge management tool for Central Queensland coalmine practitioners, in Proceedings Life-of-Mine 2016 Conference , pp 39–42 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By R. J. Hundermark, L. R. Nelson

The critical importance of tap-hole design and management to furnace performance and longevity is explored through examining some of the specific matte, metal and slag tapping requirements of non-ferrous copper blister and matte converting and smelting, ferroalloys smelting and ironmaking systems. Process conditions and productivity requirements and their influence on tapping are reviewed for these different pyrometallurgical systems. Some critical aspects of the evolution of tap-hole design to meet the diverging process and tapping duties are examined. Differences and similarities in tapping practices and tap-hole management are reviewed. Finally core aspects of tap-hole equipment and maintenance are identified that are considered important to securing improved tap-hole performance and life, so pivotal to superior furnace smelting performance.

Jan 1, 2014

By E McLean

The decision making check-list and hierarchy of information for process and plant design is generally wide-ranging and complex. The nature of grades, mineralisation and ore types in an ore body, its mine development sequence, and the body of results from metallurgical and physical test work present complex and competing influences on flowsheet development, values for design, equipment selection, plant efficiencies and operating strategy. The challenge is how to manage all these variables, to understand their impacts on performance, and how best to provide a cost-effective plant design and robust process that meets daily/weekly/monthly operating objectives. Throughput, production and grade or product specifications need to be met. The ore body is not average; its range of metallurgical and physical characteristics may be moderately to highly variable. This paper assesses some of the key competing influences and conflicting issues in design and equipment selection, and their effect on production and performance expectations.

Aug 8, 2011

By Pierre Shields, Luiggi Sassarini, Richard Zandstra, Thomas Li

The intent of this paper is to demystify the mythology which often confront mine owners and engineers faced with this dubious question “Is it better to develop or continue a ramp or make a vertical shaft to access the new ore body of interest?” trough out measuring risk and return using probabilistic analysis and unhidden cost the affect long term decision such ventilation.

Sep 1, 2017

By Nagarajkumar BV

Pavai-and TeampT JV started working on the project T49A, Sumbar J & K State as part of slope and earth stabilization for ongoing Banihal - Katra Railway Connection Project. This project has several tunnels and bridges with slopes that are protected with various types of protection system such rock bolting, rock anchors, and micro piles. For the main two bridges Bring number 2 and 3 at T49 A location Pavai - TeampT JV has to design and execute the circular group of micro piles (Fig.1) for deep excavation of earth for the purpose of construction of well foundations (CAISSON FOUNDATIONS) for both bridge 2 and 3 piers. In this paper we discuss about the purpose, basic design, detailed design approaches and actual work implementation of micro pile with composite rock bolt applications and permanent rock anchors for slope stabilization works in this project.

Nov 1, 2022

By Antonio Esposito

Saving energy and reducing pollution by minimizing emissions are today great challenges in the coking industry worldwide. In order to achieve satisfying results, equipment as well as technology should be continuously improved and updated. The most modern design tools should be adopted to maximize the coke production rate also ensuring the best coke quality. In this scenario, Paul Wurth is realizing the new coke making plant of CSPecem, Ceara - Brazil. These batteries are based on Paul Wurth “jumbo oven concept”. This solution incorporates all most modern features and design upgrading, in the aim of an easy and long-lasting operation putting a particular attention to environmental performances: the reduced number of ovens and the low number of pushing per day have the main effect of reducing pollution sources. Finally the paper will highlight Paul Wurth SOPRECO® System, which is foreseen to be installed in CSPecem batteries. SOPRECO®, which is capable of controlling the pressure for each individual oven in a coke oven battery, is thus able to reduce volatile emissions through doors, roofs and stand pipes up to 90%. The coke oven gas (COG) produced during the carbonization process is cleaned in a coke oven gas treatment plant to the level stipulated by applying the Best Available Technology (BAT).

Aug 1, 2018

By Carlton M. Ray, William P. Levy, Thomas Lindberg

"The District of Columbia Water and Sewer Authority (DC Water) is implementing its $2.6 billion DC Clean Rivers Project to reduce combined sewer overflows to the District’s receiving waterbodies and mitigate chronic sewer flooding in District neighborhoods. The First Street Tunnel project is a major component of the DC Clean Rivers Project, designed to mitigate sewer flooding and basement backups in the District’s historic and densely populated Bloomingdale neighborhood. Bloomingdale has been historically affected by sewer flooding and was severely impacted by four storms in the summer of 2012 that caused significant damage to homes, the environment and public property. As a result, DC Water accelerated the design and construction of the First Street Tunnel in order to mitigate the effect storms have on the undersized sewers serving the neighborhood. The infrastructure designed to mitigate flooding, including the tunnel, are located within the highly urbanized neighborhood – with some structures being less than ten feet from residents front door steps. The success of a large public works project of this magnitude and in this unique location depends on a well informed and supportive public. With the local community impacted by flooding but concerned about heavy construction impacts, this paper details the components of a successful public outreach plan and lessons learned throughout the design and construction process. Early identification of community mitigation, working cooperatively with stakeholders and frequent dissemination of accurate information required the project team to establish a culture of problem solving collaboration with the community. BACKGROUND Chronic Flooding in the Northeast Boundary Sewershed The Northeast Boundary sewershed, in which the Bloomingdale neighborhood is located, is served primarily by a combined sewer system and has a long history of chronic flooding problems during moderate to severe storm events. The sewer system that serves the Northeast Boundary drainage area was constructed by the Federal Government in the late 1800's when developed areas of the District terminated at what is now Florida Avenue. Since construction of the system, population within the sewershed area has grown at an exponential rate. In meeting the growing needs of the population, the District experienced development that transformed previously low-density rural areas into new communities. Impervious areas have increased drastically since the sewer system was constructed and consequently, the existing sewer system does not have the capacity to convey storms with return frequencies beyond the 2-year storm without flooding. As a result of the capacity limitations, many of the low-lying areas have become chronic flooding areas due to the surcharging of sewers."

Jan 1, 2016