Search Documents

By D Kent, R Paine

"Automated mining systems are increasingly being seen as a key requirement for a productive mining operation in the future. The importance of an integrated communication network infrastructure to support such systems is growing.This paper outlines the introduction of automated mining systems in large conventional mines as well as their growing role in block cave mines currently operating or being developed. The paper will then focus on a case study of how the communication infrastructure is fundamental to the operation of such systems and explain why the resultant communication networks require much more than just increased bandwidth (data capacity) to properly support the automation system within the overall mine operation.Mining operations already embarking down this road are discovering that the required network must be based on a true enterprise level architecture to not only enable the mine’s current plans for remote and automated mining, but also provide a scalable and integrated platform for future developments and requirements. The emerging issues for the communication network to truly support automation systems include: increased complexities of operating and maintaining multiple networks integration issues with disparate systems problems with reporting particularly as demands for corporate reporting and compatibility with enterprise systems become the norm ongoing management challenges, which will only increase with the proliferation of new technologies.The paper will explore how certain mining operations are addressing this by adopting a long-term strategy for automation deployment, which includes laying the necessary foundation architecture to meet their current requirements, while supporting their future visions for the fully automated mine.CITATION:Paine, R and Kent, D, 2014. Developing the foundation communication infrastructure to support remote and automated mining initiatives in underground mines, in Proceedings 12th AusIMM Underground Operators’ Conference 2014, pp 151–158 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 24, 2014

By D R. Seaman, B Adamson, P Sharman, M McMahon

"The Telfer processing plant commissioned its pyrite regrind and flotation circuit in August 2012. The circuit was designed to regrind pyrite concentrate to a p80 of <30µm then float a gold and copper rich concentrate before tails from the flotation circuit fed the carbon-in-leach (CIL) circuit downstream. Expected benefits were: improved CIL performance that would result from the finer grind and a reduction in cyanide soluble copper to the CIL circuit, as well as a small increase in overall flotation circuit recovery. While the benefits of a finer grind were soon realised, recovery in the post-regrind flotation circuit (named the ‘pyrite recleaner circuit’) was consistently and significantly lower than that expected based on laboratory test work. Selectivity in the pyrite recleaner circuit was virtually nil and copper reporting to the CIL circuit did not change as a result of the pyrite recleaner circuit operation.A pulp chemistry survey of the plant and comparison with the lab showed that the dissolved oxygen (DO) demand in the plant was much higher than that in the lab. Lab flotation tests conducted using nitrogen gas instead of air resulted in recoveries similar to those from the plant. It was identified that the freshly ground pyrite surfaces exiting the regrind mill were consuming oxygen in the slurry and there was insufficient oxygen available for collector adsorption and pyrite depression to occur. Test work, using a pilot regrind mill, showed that a reduction in grind size resulted in an increase in DO demand.A range of oxidising agents were tested in the laboratory and using a pilot flotation rig set-up in the plant. Oxygen was found to be the most reliable and effective agent and options for increasing oxygen delivery to the plant were explored. Scale-up from the lab oxygen requirement to the plant is difficult and efforts to implement a permanent solution for meeting the DO demand in the plant are ongoing.Citation:McMahon, M, Seaman, D R, Sharman, P, Adamson, B and Seaman, B A, 2016. Optimising the Telfer Pyrite Regrind Circuit - Effect of Dissolved Oxygen Demand, in Proceedings 13th AusIMM Mill Operators’ Conference 2016, pp 51–58 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 10, 2016

By Hegedus M

The Hydrogeological Survay of the bauxite mines in Hungary was establisned 30 years ago. The goal of the HS has been to collect the all available date needed to solve the hydrogeological problems of bauxite mines. The results of activity of the HS have been summarized in the annual reports-. This report is going to present a few methods to evaluate the hydrogeological properties of fissured, karstic rock ie. the evaluation of drilling mud losses, the statistics of core samples evaluated by a special computer program for calculation the porosity and permeability of the rocks. An experimental injection test is presented together with the development of a new portable instrument to get signes of the water table change during the injection test in every two second. It can be proved that the flow around the well may be a transient one if the yield of the injection exceeds a definite one (Figure 2.). It was observed that the permeability calculated from the pumping test date may be 1.2-1.6 time higher than it coming from the injection test. A practical example is presented also how to use the results of the HS for designing the dewatering of a new mine together with an analogous computer model to forecast the yield expectable for making the drift tunnel. A suggestion based on the hydrogeological feature has been done for the dewatering without using electric energy (see Figure 3.-6.).

Jan 1, 1988

By M Tsai

Tube bundle gas monitoring systems have been used in the mining industry for over 50 years. The initial design was based on four individual gas analysers along with a series of solenoid valves, gas sample conditioning and flow control mechanisms to ensure the correct gas flow stream volume to the analyser. Simtars staff have identified flow control issues when providing operational support to coalmines on numerous occasions. The accuracy of the oxygen analysis is dependent on control of the gas flow to the analyser. Oxygen is one of the parameters used in calculating Graham’s ratio which is used for the detection of spontaneous combustion activity in coalmines. This paper will provide data which identifies the flow control issues by comparing mine site records for the two surface sample lines in the analyser room and the gas cage. Mine sites will be deidentified within the paper. The paper will discuss some of the changes that have been made in modern tube bundle systems and compare the change to the initial design specification developed by the UK National Coal Board, investigate possible operational impacts and provide a technical fix to solve the current flow issues being experienced at some mines.

Oct 12, 2022

By T Brown

Australia is now committed to the most significant period of infrastructure investment since the 1960s and the current climate of project finance and public private partnership (PPP) model uncertainty means it is imperative that the affordability and certainty in delivery of infrastructure projects is maximised.In light of the current and forecast levels of infrastructure investment it is worth drawing comparison with a similar period of Australian expansion when the nation’s first railways were constructed. Similarly to over a century ago, we are following a trend in rapid development and are already reaping the inefficiencies that could be avoided with broader technical planning and improved client coordination.The original rail networks were developed by the individual states before they combined to form a Federation of states in 1901. As a result of the adoption of different gauges by 1917 a passenger wanting to travel by train from Brisbane to Perth had to change trains six times.Similarly in 2011, there is little parity between Australian states on the quality requirements (performance specifications) for road tunnels. Differences between states start most significantly with the size of the specified traffic envelopes, thus the size of tunnel required. Where ambiguity and differences exist in project documentation, performance specifi cations (PS) and broad technical requirements for road tunnel projects, any associated risk in interpretation ultimately ends up being incorporated in the bidder’s (constructor’s) final sell price.Whilst not nearly as inconvenient as having to change train at each state border, and largely unnoticed by the general tax paying motorist, this paper examines examples of apparent minor differences in Australia’s recently constructed road tunnels to highlight the differences in road tunnel specifications.The paper identifies how these small differences manifest themselves in major price penalties between projects and further, highlights the need for further specification review, refinement and standardisation across road tunnel jurisdictions to increase road tunnel affordability.

Mar 8, 2011

By N Clarke, J Hunt, A Barros, N Guerrero, L Keeney

Grade Engineering® (GE) involves a range of integrated technologies and operating protocols for improving effective feed grade through early rejection of low value material prior to costly processing activities and has the potential to transform the economics of large, low grade, mining operations. Extensive GE test work by AngloGold Ashanti (AGA) and the Cooperative Resource Centre for Optimising Resource Extraction (CRCORE) determined that the Gramalote gold deposit in Colombia is highly amenable to implementation of grade-by-size screening to upgrade the ore at a production scale. To understand the relationships between geology and the upgrade response drill core and bulk samples were analysed at the Centre for Ore Deposit and Earth Sciences (CODES) as part of a larger CRCORE project to understand geological controls on grade-by-size deportment, i.e., the tendency for specific mineral phases to preferentially fractionate during breakage into different size fractions. This work is focussed on understanding the role of mineralogy and texture in influencing rock breakage and natural fractionation at a range of scales. Detailed logging of Gramalote drill core and mineralogical analyses including hyperspectral logging, portable and bench-scale X-ray fluorescence (XRF), plus low resolution Laser Ablation of intact drill core pieces, combined with data from site (drill logs, geochemistry, petrophysics) were used to evaluate the ore and alteration mineralogy, vein paragenesis and textural variability. This provided information on gold deportment and allowed the identification of favourable host veins. Bulk sample material from different ore grade zones was also analysed. A comparison with the results of GE testing shows that positive upgrade results are produced by rocks with abundant veins, particularly those associated with potassic and/or white mica alteration. This work indicates upgrade response can be predicted from drill core using data collected by a combination of automated systems including hyperspectral data, XRF, and detailed drill core logging.

Nov 10, 2020

By G Deans, M Longbottom

OZ Minerals’ Carrapateena mine is one of Australia’s newest ‘greenfield’ mining deposits. It will be a 4.25 Mtpa sub level cave underground operation, with an estimated mine life of 20 years. The integration of stakeholder values to inform project development influenced the social and environmental outcomes. A Native Title Mining agreement was developed in 12 months. Project primary approval was obtained 12 months from submission, with achievable licence conditions and one public comment. The project moved from a Pre-feasibility Study in 2016 to construction in 2018. Following recent international dam failures, the Tailings Storage Facility (TSF) was a focus for Government approvals and stakeholder engagement. Significant effort was made into understanding the science around potential effects, impacts and risks. A leading practice Impact Assessment Framework that identified Sources, Pathways and Receptors was applied. A process of failure mode identification and layers of protection analysis was undertaken for robust design controls at each stage, while simultaneously transitioning between downstream and upstream discharge arrangements. Participatory selection of the TSF site and design layout was critical in managing project costs and environmental constraints, and in incorporating cultural heritage constraints and technical risks.

Jul 1, 2021

By N Boughen, K Moffat, L Brooks, A Zhang

In 2015, Ernst and Young (EY) ranked socio-political license to operate (SPLTO) as the fifth greatest challenge to the mining sector (EY, 2015). The EY report asserts that SPLTO will continue to present a risk to the mining sector in the context of ‘increased activism, digitally connected stakeholders and politicians who need to respond to general consensus’. While there is no consensus on a definition, SPLTO is commonly regarded as the ongoing acceptance or approval of an operation by affected stakeholders (Moffat and Zhang, 2014; Thomson and Joyce, 2008) as well as those stakeholders that can affect the operation (Graafland, 2002). Warhurst (2001) relates the process of stakeholders granting SPLTO to the establishment of meaningful partnerships between operations, communities and government based on a variety of factors that build trust between stakeholders.From these accounts, we can see that understanding stakeholder attitudes about company performance and impacts on stakeholders directly affected by an operation are important in any attempts to measure SPLTO. Understanding the level of acceptance of an operation within these stakeholders provides a good proxy or outcome measure of SPLTO. Moreover, trust seems to be a central variable in the translation of these experiences of an operation into acceptance. What the mine or company does, its behaviour, degrades or builds trust with stakeholders, and this then affects acceptance (Moffat and Zhang, 2014).In addition, a strong emphasis is placed on the nature of the relationship between companies and stakeholders as influenced by inter-group interactions. It is not just what companies do well or poorly with respect to environmental impacts, for example, that will determine trust and acceptance, but how the company relates to its stakeholders at personal and group levels.These relationships between communities of stakeholders and extractive companies are dynamic. Brown and Fraser (2006) recognised the importance of industry being able to respond to the changing nature of societal approval and acceptance, arguing that ‘business must have regard for evolving social attitudes and expectations if it is to maintain its ‘social licence’’.This paper will describe a series of five pilot projects conducted by CSIRO with Anglo American in Australia and South Africa to generate a real-time understanding of SPLTO to guide more reflexive and effective social performance strategies.CITATION:Moffat, K, Boughen, N, Brooks, L and Zhang, A, 2016. Social licence in real-time – using dynamic methods to support a new kind of community relationship, in Proceedings Life-of-Mine 2016 Conference, pp 191–194 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By Jianmin H, Shuqin L

This paper analyses problems associated with cement based technique in metal mines, and provides a new mining technique of packing the tailing sand and water into solidified material. In the new technique, the cementing agent is a solidifying material containing a high percentage of water and tailing sand. The sand and water solidify into the packed body at the same time. The slurry of the packed body varies widely in concentration and suitability for different mining conditions. It consists of two liquid materials, each composed of a cementing agent, tailing sand and water. The thick liquids are transported to the packing place at the same time. Their pumping property is good; they do not solidify or block up the pipe during transportation. At the packing place, the two liquids are evenly mixed.The mixed liquid flattens out well and its solidifying speed is so fast that it solidifies into a packed body within a very short period of time. The compressed strength of the packed body can reach 1.2-5MPa in one day, which satisfies the requirements of different mining conditions. By using the new mining technique, all the tailing sand can be used again in the packed body and it is low in cost and investment. The mechanisation is easy and thus the working efficiency is increased and the use of labour decreased. Contamination problems caused by i. Dr & Prof. Beijing Graduate School, China University of Mining Science and Technology,Beijing,China 2 Northern .Jiaotong University, Beijing,China 3. Beijing Graduate School, China University of Mining, Science and Technology

Jan 1, 1992

In considering the organization of research, it is necessary to know just what research is, what objects are in mind when setting out to conduct research, and what are the functional units which are required to enable a coordinated effort in research to proceed.The dictionary defines research in the following terms: Laborious and patient search, as for truth, diligent inquiry or examination in seeking facts or principles; inquiry, scrutiny; to search or examine with continued care; to seek diligently; to search again; to examine anew.This is, of course, simply a formal definition, but the reference to "labour", "patience" and "diligence" should be noted.The following quotation from an answer to the question "What is Research?", published recently in a technical journal, puts some life into the formal definition:- Essentially, it (Research) is nothing but a state of mind a friendly, welcoming attitude toward change. Going out to look for a change instead of waiting for it to come. Research, for practical men, is an effort to do things better... The research state of mind can apply to anything: personal affairs or any kind of business, big or little. It is the problem-solving mind as contrasted with the let-well-enough-alone mind . . . It is the "to-morrow" mind instead of the "yesterday" mind. Note the statements that: Essentially, it (Research) is nothing but a state of mind, and the research state of mind can apply to anything.

Jan 1, 1950

By P Standish

Qualitative risk assessment methods are not well suited to considering complex systems and potential interactions of new technology. As part of supporting tier one mining organisations and international industry groups, the author and colleagues have innovated processes to help provide better solutions to sites/companies considering a move to implementing proximity detection and collision avoidance systems. The process identifies required operating states for the system. By applying a combination of research and team-based analyses, a rigorous identification of credible failure modes which could cause these states to be lost, is identified. Finally, required business inputs, expressed in practical terms are distilled from regulator, industry, organisation and site in a way which clearly addresses the failure modes and so retain the required operating states. These business inputs identify improvements for site arrangements (EMESRT levels 1 to 7) before identifying functional requirements for technological collision avoidance solutions (levels 8 for advisory and 9 for autonomous). The paper presents a case study synthesised from multiple sites analyses and will provide guidance on where to find additional resources to assist in making the best possible transition to better equipment and road network solutions.

Jun 22, 2022

By A Fern, A Hawkes, o

This presentation will cover: the importance of high-quality safety leadership; insights from a Safety Climate Survey that includes responses from 7903 employees working at 19 Australian mining organisations; the results of a critical control verification (CCV) coaching intervention; and recommendations for improving safety leadership in high-risk work settings. Safety climate is a representation of the deeper culture that exists in an organisation. Safety climate is predictive of behaviour, performance and reporting in organisations. Leaders play an important role in the establishment and maintenance of culture. Perceptions of safety climate were collected from 19 Australian mines (n = 7903 employees). These results indicate that the Australian mining sector is doing well in team support for safety and supervisor safety commitment. There were negative perceptions of willingness to report errors, employee involvement in safety initiatives, psychological safety and emergency readiness. Perceptions of safety leadership were in the fair range, with recognising behaviours perceived lowest, falling in the poor range. The underreporting rate was at 25 per cent indicating that 1 in 4 incidents are not being reported. Analyses exploring climate, leadership, safety behaviour and well-being will also be discussed. The integrity and success of critical risk management systems is often determined by the quality of safety leadership. Leaders need a mix of technical safety knowledge and interpersonal skills to be able to support the workforce to build critical control knowledge that invites open and collaborative discussions to find new or improved solutions. Forty leaders at a major mining operation completed training and 5-weeks of coaching focused on developing critical control verification competencies. The follow-up evaluation demonstrated significant improvements in relationship building, observation of controls and overall capability. Overall, insights from multi-organisation climate data and a prepost coaching intervention will be discussed and recommendations and practical guidance for leaders will be provided.

Apr 16, 2024

By S H. Burgmans, B Anderson

This paper aims to define the specific challenges relating to dredging fine tailings from an above ground storage facility for transferral to a mined-out pit. In addition, it compares dredging and mining perspectives on dredging of fine tailings.

Jul 1, 2021

By N J. Potter, N W. Brand, J M. F Clout

The increasing demand for iron ore with low concentrations of trace elements, puts increasing pressure on iron ore producers for high-quality material. Understanding the mineralogy, petrography, chemistry, and mineral association of iron ore deposits is becoming increasingly important to provide iron ore products that meet the ever-increasing standards of steel mills. Limited attention has been paid to documenting new orebodies beyond bulk RC drill chip assays and product specification data. Therefore, limited information is known about the spatial distribution of minor and trace elements at the hand specimen scale, and elemental deportment within different ore and gangue minerals. In this study, samples from high-grade microplaty hematite, supergene-enriched martite-goethite and hematite iron ores are examined for their elemental and mineral associations. These samples contain distinctive minor and trace element distributions, with the mapping of deleterious elements (eg Zn, As, Cu) enabling the deportment and abundance within the ore and gangue minerals to be assessed. Results from this study show a diverse range of minor and trace mineralogy that are present in typical iron ore samples, in abundances below the detection limit of routine XRD scans, that host the deleterious elements, including but not limited to, sphalerite (Zn and S), chalcopyrite (Cu and S), xenotime (P and Y), apatite (P and Ca), cryptomelane (K and Mn), barite (Ba and S), alkaline feldspar (K, Al and Si) zircon (Zr and Si) and chromite (Cr and Al). The presence of these minerals and associated deleterious elements, even at low concentrations, has implications for producers, with the ongoing restrictions and tightening of environmental constraints in shipped iron ore products. By understanding the distribution and location of these elements within the iron ore, steps can be considered to maintain increasingly higher quality iron ore supply around the world.

Nov 8, 2021

By C M. W Boyle, E K. C Phuak, A Lewan, E Ryan, M D. Paine, P H. Mackenzie

"Rio Tinto Iron Ore (RTIO) has an extensive history in the application of geometallurgy to the iron ore value chain. Fundamental to this has been the geological logging of material types which are assigned processing attributes such as lump per cent and density. Initially these were used for product (lump and fines) grade predictions in relation to grade blocks to be used within short-term planning horizons.More recently the predictive reach of the material types and their associated processing attributes has been extended due to their inclusion into geological block models. These predictions can now be used to influence mine plans across multiple planning horizons in such a way that the extremes of geometallurgical properties can be pre-empted and managed thus improving efficiency. Spatial material type domains are also used in the planning of metallurgical drill holes to ensure greater representivity of material than was typically obtained by chemical and/or stratigraphic criteria alone.Material type logging has also been enhanced by the introduction of modern, rapid mineralogical techniques that have complemented visual logging. This has enabled the identification and quantification of contaminant minerals and their relationships with host ore types to be established. This data is used to better manage product grade predictions and identify risks to the short-term plan.Work is ongoing in RTIO to further refine logging based predictions and in addition apply them to new areas of the business. This work requires collaborative and multidisciplinary teams working on an integrated approach combining geology, metallurgy, technology and innovation, mine planning and technical marketing.CITATION:Paine, M D, Boyle, C M W, Lewan, A, Phuak, E K C, Mackenzie, P H and Ryan, E, 2016. Geometallurgy at Rio Tinto Iron Ore – a New Angle on an Old Concept, in Proceedings The Third AusIMM International Geometallurgy Conference (GeoMet) 2016, pp 55–62 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jun 15, 2016

By G P. S Resende, D E. G Oliveira, E A. S Baeta, T F. Bravin

There is currently in the mining industry, as well as in other industries, a movement seeking to increase investments in decarbonisation processes to help combat global warming. Among some initiatives taken is replacing diesel-powered mobile equipment in the mines with electricity-powered equipment, such as electric off-highway trucks or even belt conveyors in the mining operation. Samarco is a Brazilian mining company that since its conception has used a conveyor belt mining system in its mining operation, using only a small number of trucks to complement the mining process. This mining process that combines conveyor belts and trucks has brought environmental gains for the company since the environmental impact of conventional truck-only mining is greater than that of the combined system. To measure these gains, a medium-term mining plan was developed in which two fleet scenarios were detailed. One scenario contemplated a high level of detail of belt mining seeking its maximisation, while the other considered the operation performed 100 per cent by trucks, eliminating the use of conveyor belts. Through the comparison of these two scenarios, it was possible to make an inventory of atmospheric emissions and greenhouse gases for each one of them considering data such as types of equipment, diesel consumption, total distance travelled and energy consumption. The results showed that the fleet scenario with conveyor belts results in periods with up to 15 per cent less greenhouse gas emissions and 37 per cent less total particulates compared with the truck-only scenario. Therefore, the results confirm the environmental benefits of the method and the need to look for ways to even expand it in future operations through a study to identify the potential areas in the long-term mining plan.

Sep 18, 2023

By M A. Noppé

Mining is inherently a risk-based business and risk governance is an integral part of corporate assurance and business decision-making. Mineral Resources and Ore Reserves are the key assets for a minerals company and senior management/company boards require assurance regarding the likely accuracy of estimated and reported technical information. Reviews and audits improve the level of assurance in the reliability of estimated short-term (grade control) estimates, reconciliation, Mineral Resources and Ore Reserves.Peer reviews and audits contribute not only to governance processes, but also provide valuable technical improvement opportunities, as well as mentoring and professional development guidance to those whose work is being reviewed. Technical review is particularly crucial at a time in the industry when companies are running lean or perhaps inexperienced teams, with limited technical or management oversight.Despite both industry guidance and some companies’ standards expecting or requiring reviews and/or audits of Mineral Resource and Ore Reserve generation and reporting processes, it is surprising how infrequently or ineffectively these are actually carried out. Examples of governance systems are presented, which include appropriate peer review processes that if effectively applied, can identify shortcomings in technical processes and provide timely correction to prevent, or mitigate against, erroneous outcomes.Peer reviews are ideally carried out concurrently with the preparation of data, selection of estimation procedures and validation of outputs from Mineral Resource and Ore Reserve estimation prior to the handover of results between disciplines, or the final reporting of results. Audits, on the other hand, are generally retrospective reviews by independent and/or external reviewers who rate the risks inherent with an already completed process, identifying opportunities for improvements in the future.This paper outlines the main components of peer reviews and audits, discussing how a combination of these can provide a structured and objective assurance system leading to systematic and disciplined processes to improve the effectiveness of, and confidence in, grade control, reconciliation, Mineral Resource and Ore Reserve risk management, and support good governance.CITATION:Noppé, M A, 2017. Improved assurance for Mineral Resource and Ore Reserve estimates and reporting through peer review and auditing, in Proceedings Tenth International Mining Geology Conference 2017, pp 143–148 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

By L Tatnell, R Mackay, A Tolooiyan

The multi-reversal direct shear test (MRDS) method is commonly used to measure the residual shear strength of soils. However, when the standard direct shear (DS) apparatus is used, the MRDS method is prone to two major sources of error: load cap tilting and specimen loss. These two sources of error can cause erratic behaviour in the residual shear strength curve, making it difficult or even impossible to determine the correct residual shear strength value of the specimen being tested. This paper presents the results of new modifications to the standard DS apparatus that prevent load cap tilting and specimen loss. Consolidated drained testing was performed on highly-over consolidated cohesive soil samples from a Latrobe Valley open pit mine, with results obtained from the modified DS apparatus showing a great improvement in the residual shear strength profile compared to those obtained using the standard apparatus. Large numbers of reversals (up to 14) conducted on a single specimen in the modified DS apparatus showed no notable load cap tilting and no specimen loss occurred. The modifications are easily applied to the standard DS apparatus, and analysis and correction of the data are simple.CITATION:Tatnell, L, Tolooiyan, A and Mackay, R, 2014. Measurement of residual shear strength using a modified direct shear apparatus, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference , pp 425–434 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 5, 2014

By N Gupta, R Trivedi, S Bhandari

Managing blasting operations in four mines surrounded by villages is a challenging task. This study aims to compare the blast-induced flyrock as observed in opencast mines by predicting flyrock distance using a soft computing approach known as an adaptive neuro-fuzzy inference system (ANFIS) and Flyrock Predictor software based on empirical studies. Blast design and geotechnical variables such as linear charge concentration, burden, stemming length, specific charge, unconfined compressive strength and rock quality designation were selected as independent variables, while flyrock distance was used as a dependent variable. Out of 120 blasts, data from 100 blasts was used to train and test the ANFIS model. Flyrock distance for the remaining 20 blasts was used to evaluate the model. Flyrock distance has also been predicted using Flyrock Predictor software based on an empirical approach using the same data sets as those used for ANFIS. Performance indices like root mean square error (RMSE), mean absolute error and coefficient of determination (R2) were evaluated to compare the reliability of ANFIS and Flyrock Predictor quantitatively. ANFIS was found to be a better predictive tool, with 1.75 m RMSE and 0.966 R2 compared to Flyrock Predictor, which returned RMSE and R2 values of 2.48 m and 0.932 respectively.CITATION:Trivedi, R, Singh, T N, Gupta, N and Bhandari, S, 2015. Soft computing approach to predict blast-induced flyrock, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 455–462 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By E Wargem

The conventional method of underground mining involves a process known as drilling and blasting to excavate valuable ore bearing minerals through the load and haul process. Drilling and blasting processes are completed for both the development of the tunnels used to access the orebody and for mining out the orebody itself. The former being called development drilling and blasting, and the latter production drilling and blasting. In either development or production drilling and blasting, the effective recovery will be largely reliant on the extraction of the initial void created in each blast cycle. In development tunnelling, the initial void is commonly known as a Burn Cut. The initial void created in production drilling and blasting has many names such as a Slot, Winze, Rise or Raise. There are drill patterns and charge designs used to create these initial voids in the production cycle. This paper discusses common slot or winze designs for production drilling and blasting; and various critical design criteria for these. The document also aims to provide a process for completing desktop reviews of current patterns employed on-sites and provides an initial guide in a process for improving the recovery of a slot, winze, rise or raise in underground mines.

Mar 29, 2023