Paterson & Cooke Mine Backfill – Design and Operation Course
6 May 2019 | Ballroom, The Westin | Cape Town, South Africa
The one day backfill course will introduce the fundamental concepts of geomechanics and material properties that
underpin decision-making when developing a backfill design. The course will examine the various elements that go into engineering and operating a backfill system,including plant/process design, underground reticulation design and backfill management planning.
|Welcome and introduction|
|Backfill study stages and testing||Study levels – scoping, pre-feasibility to feasibility|
|Pros and cons of paste and hydraulic fill|
|Backfill testing programs|
|Sizing a plant and utilisation factors|
|Backfill system design||Design criteria|
|Case studies/various examples||Design pitfalls|
|Pipeline distribution system hydraulics||Background|
|Hydraulic backfill versus paste backfill flow|
|Case study – pipeline wear||Pipeline wear experience|
|Backfill placement and monitoring considerations||Strength requirements|
|Advances in pour monitoring|
|Rise rates and pressures|
|Backfill system management||Scheduling|
|Wrap-up||Questions and discussion|
ACG Is the Future Filtered? Paste and Thickened Tailings Short Course
7 May 2019 | Ballroom, The Westin | Cape Town, South Africa
Thickening of mine tailings is now going beyond the use of large, deep thickeners and addressing a new challenge – filtration of tailings to produce a low water content material that should pose much lower environmental and safety risks than most conventional TSFs. Tailings filtration provides many potential benefits, including improved water recovery and the ability to deposit and compact the filtered tailings to form a stable, engineered landform. However, there are also many concerns and potential pitfalls in adopting a filtered tailings management system, including high capital costs, equipment reliability, clogging of filter cloths, appropriate wash systems and optimisation of placement techniques. Although in the past it has been considered unachievable, large-volume filtered tailings operations are beginning to emerge and there are already a number of operational facilities dealing with medium volume (to the order of 20 ktonne/day) throughputs.
Given the increasing scrutiny of the mining industry and its relatively poor record with regards to mine tailings management, increased requirements to minimise water usage (often accompanied by very high costs of water) and the need to demonstrate achievable long-term closure strategies, it is likely that the option of a filtered tailings system will need to be considered in many operations in future.
It has therefore been decided to dedicate a short course to this topic to provide practitioners and decision-makers with as much information as possible, as early as possible.
Drawing on experiences from a number of operational filtered tailings facilities, the short course will discuss available technologies,
appropriate test programmes to determine relevant design parameters, operational challenges and cost comparisons.
Designers, consultants, owners and operators, mine planners, regulators and researchers would all benefit from attending this short course, which will provide a valuable opportunity to examine a rapidly growing technology that is likely to see increased adoption in the future.
Click to view the preliminary programme (subject to change)
07:30 Course Registration
08:20 Welcome and introduction Professor Andy Fourie, The University of Western Australia
08:30 Solid liquid separation - Old technologies applied to new applications: Fundamentals of tailings filtration technologies Wilfried Wimmler, Innovative Filtration Solutions Pty Ltd, Australia
09:00 Filtered taillings experience at Skorpion zinc mine: Design and 15 years of operation Andrew Copeland, Knight Piésold (Pty) Ltd, South Africa
09:30 Filter-pressed Dry-stacking: Alternative tailings management approaches Colleen Crystal, SRK Consulting (Canada) Inc., Canada
10:00 Morning Break
10:30 Large scale filtered tailings: Saving costs and improving safety Todd Wisdom, FLSmidth, USA
11:00 Filtered taillings for all: Case histories for value in small operations Scott O'Brien, McLanahan Corporation, USA
11:30 Geotechnical considerations Professor Andy Fourie, The University of Western Australia, Australia
13:00 Filter applications in mine backfilling Rob Brown, Paterson & Cooke Canada, Canada
13:30 2016 Luoyang, China: Tailings storage failure Dr David Reid, The University of Western Australia, Australia
14:00 Dry stacks: How dry is dry? Bryan Ulrich, Stantec Consulting Services Inc., USA
14:30 Afternoon Break
15:00 Transitioning to no tailings dam for a coal washing plant Amol Chinchankar, Alfa Laval, Sweden
15:20 Dry stacking at every latitude Andrea Grosso, Aqseptance Group Srl, Italy
15:40 What is the ideal method to dewater tailings? Christophe Bellot, Weir Minerals B.V., The Netherlands
16:30 Course Close
Technical Director Mining
Knight Piésold (Pty) Ltd.
Presentation: Filtered tailings experience at Skorpion zinc mine – design and 15 years of operation
Andrew is a director of KP RSA and a technical director mining (non-statutory): KP Africa at Knight Piésold’s Head Office (Rivonia). He has had extensive exposure to international mining industry and to the full chain of mining activities and project stages. Andrew is a technical specialist in the area of mineral residue management and has a thorough understanding of the associated infrastructure, environmental, social and economic aspects, including paste and thickened tailings. He has substantial experience in civil geo-technics, heap leach facilities and mine infrastructure. Andrew has also written guidelines and standards for mine residue facilities and carried out numerous audits around the world.
SRK Consulting (Canada) Inc., Canada
Presentation: Filter-pressed dry-stacking: Alternative tailings management approaches
Colleen Crystal, PEng, is a Principal Consultant with SRK engineering with over 23 years of experience in geotechnical engineering and seismic analysis and design for earthen embankments, landfills, mine-waste tailings and waste rock facilities and water retention dams. Ms. Crystal is the geotechnical lead for the siting, design, construction and operations of several recent filter-pressed dry-stack storage facilities in high seismic risk areas including the El Escobal silver mine in Guatemala and the Buritica Gold Mine in Medellin, Colombia. For these and other waste management facilities she has managed the preparation of PFS/FS and trade-off studies as well as providing detailed design plans and specifications, surface water management plans, OMS manuals, risk assessments and Risk Management Plans in conformance with current international standards of good practice.
Professor Andy Fourie
Professor of Civil and Mining Engineering
The University of Western Australia, Australia
Andy is a Professor in the School of Civil, Environmental and Mining Engineering at The University of Western Australia in Perth.
He has Bachelors and Masters degrees from the University of the Witwatersrand in South Africa, and a PhD from Imperial College, University of London. He has worked at the University of Queensland, the University of Witwatersrand and has been a visiting professor at the University of Alberta, the Catholic University of Valparaiso in Chile and the University of Colorado in Boulder. His research is in the field of mitigating the impact of mining and municipal solid waste disposal. Outcomes from his research have been incorporated in changes to environmental legislation in South Africa. He contributed to a series of Guidelines for managing mine tailings in Australia, as well as developing a document for the International Atomic Energy Association on barrier systems for retaining uranium mining waste.
McLanahan Corporation, USA
Presentation: Filtered tailings for all: case histories for value in small operations
Paterson & Cooke Canada, Canada
Presentation: Filter applications in mine backfilling
Rob Brown is the Principal of Paterson & Cooke’s Sudbury, Ontario practice, a Director of P&C (UK) Ltd. and is the President of Paterson & Cooke Canada Inc. Rob leads P&C’s global backfill group and has worked on backfill and surface paste tailings applications since 1997. He specializes in paste fill and has extensive international experience with plant/reticulation design and construction, commissioning, training and underground backfill placement. Much of his career has been spent in the field starting up new backfill operations, troubleshooting existing systems or running contracted backfill projects. Rob is a Professional Mining Engineer and frequently participates in system audits and peer reviews as a Subject Matter Expert. He has authored several technical papers and operating manuals covering the safe design and operation of paste backfill systems.
Dr David Reid
The University of Western Australia, Australia
Presentation: 2016 Luoyang, China: tailings storage failure
The University of Western Australia, School of Civil, Environmental, and Mining Engineering
David is a tailings engineer with 14 years’ experience in the design, laboratory testing, investigation, and analysis of tailings and tailings storage facilities. He is primarily involved in laboratory and in situ characterisation of tailings with respect to strength, consolidation, and liquefaction. David completed a PhD from The University of Western Australia, which involved studying the properties of polymer-treated tailings and the use of centrifuges to perform consolidation testing. In November 2017, David joined the UWA’s School of Civil, Environmental, and Mining Engineering for an ARC Linkage project focussed on static liquefaction of tailings.
Vice President, Geotechnical
Stantec Consulting Services Inc., USA
Presentation: Dry stacks: How dry is dry?
Bryan is a geotechnical engineer with more than 30 years of experience with engineering, project management, design and construction, analysis, closure and site investigations of mining-related work. He has participated in all aspects associated with the design of tailings and heap leach facilities. Bryan has been involved in numerous filtered tailings facility designs. He has three engineering degrees in unrelated fields. He spent four very productive years in South Africa, where he met Andy Fourie, who became one of his life-long mentors.
Innovative Filtration Solutions Pty Ltd, Australia
Wilfried graduated as an engineer in Austria and gained experience in filtration and dewatering through various applications, including domestic, industrial and ceramic, throughout Europe. He migrated to Australia in 1991 and held various roles in the industry, most times self-employed as an equipment supplier and contractor to large mining companies such as ANGLO Coal and BHP. He established a joint venture with Ishigaki Japan and for 12 years, was managing director of Ishigaki Oceania and represented the unique LASTA FILTER presses in the mining industry. He now operates his own filtration solutions and consulting company serving the industry in Australia, New Zealand and South East Asia.
Director Tailings Solutions
Presentation: Large scale filtered tailings: saving costs and improving safety
Todd is the director of tailings soutions for FLSmidth Todd has a Master of Science Degree in Chemical Engineering and joined FLS in 1993. He is currently leading FLS into the large tonnage tailings solutions market which includes the dewatering, conveying, and placement of filtered tailings.
Alfa Laval, Sweden
Transitioning to no tailings dam for a coal washing plant
Click to view the abstract
Rix’s Creek South had a vision to address their existing tailings issues and had recognised for some time that a suitable dry tailings disposal method had to be found. The existing tailings dam used on site was nearing capacity and there were no suitable alternative sites for a replacement dam.
Within this operational context, they set out to find the best solution for dewatering thickener tailings at Rix’s Creek South.
There was a device that had become an industry standard. Rix’s Creek South wanted to see if there was something better than the industry standard to handle tailings containing high levels of clays.
Four different technologies were trialled at pilot plant scale on-site for dewatering their thickener tailings from their Coal Handling and Preparation Plant. Eventually the Alfa Laval Solid Bowl Centrifuge was selected based on the outcomes of the trials.
Three Alfa Laval 720mm Solid Bowl Centrifuges were installed at Rix’s Creek South to handle part of the tailings flow. In 2018, two more new larger Solid Bowl Centrifuges were installed to handle the total volume of thickener underflow. This new installation will remove the need for a new tailings dam when the existing dam capacity runs out.
This paper will outline the process results and decision making that drove Rix’s Creek South over a few years to install Solid Bowl Centrifuges.
Senior Process Engineer, Aqseptance Group Srl, Italy
Dry stacking at every latitude
Click to view the abstract
Global Product Manager Isodry, Weir Minerals B.V., The Netherlands
What’s the ideal method to dewater tailings
Click to view the abstract Weir Minerals has developed an expert global in-house tailings group in order to share the best methods in dealing with tailings. Weir Minerals is very active in the tailings field and has an equipment range that suits any tailings solutions (pumps for slurry: Warman, high solids transportation: Geho, valves: Delta/Isogate, Hydrocyclones: Cavex, Dewatering screens: Enduron, Linatex, the range of IsoDRY equipment (thickeners, filters, centrifuges) and dewatering pumps: Multiflo 1. Traditional thickening method; however, with a pre-feed cyclone. Cyclone overflow reports to the thickener whilst the underflow reports to a dewatering screen. The thickener underflow is combined with the dewatering screen product to create an overall higher solids concentration for final disposal. This method reduces the loading on the thickener and improves the overall disposal solids content albeit using the commonly used thickening method. Transport to tailings storage where coarse material is used to build the dam walls and the overflow reports to the pond for future recovery. 2. Paste thickener with pipeline transportation, automation of the complete system to guarantee the highest solid content. 3. Centrifuge versus chamber filter press for truck disposal and TSF reduction. Our customer requires a material dry enough to be truck transported; the target dry solid content is 70%. A low-priced Capex is an critical driver. Decanter centrifuge is a better choice when compared to a low-pressure chamber filter press. It can produce a cake dry enough for truck transportation, compete on the CAPEX side, be lower on OPEX and accept the variation of underflow density of the manual thickener. 4. High pressure filter press for highest possible dryness and reduced install power.
This complete portfolio enables Weir Minerals to integrate solid/liquid separation and transportation. We present to customers a complete solution from thickening, dewatering, solids transportation, water recovery, stacking, tailing storage facility. The overall solution should always be evaluated, and the best solution is not always the cheapest CAPEX nor the highest dryness, even if this means a higher outlay cost to set up the tailings.
In the presentation, we will present several flow sheets with possible solutions as well as their pro and cons
The combination of a paste thickener and a positive displacement pump is the easiest method to dispose of slurry without free water. In this operation the automation by advanced process control and management of pumps is a must.
The pilot pipe loop test is also needed to find the optimum between solid content and pressure drop in pipe line.
Filter press is the best machine to achieve the highest dryness needed for dry stacking. We will present the various methods of filtration and their comparison from chamber press to 25bars filtration pressure.
Weir Minerals has developed an expert global in-house tailings group in order to share the best methods in dealing with tailings. Weir Minerals is very active in the tailings field and has an equipment range that suits any tailings solutions (pumps for slurry: Warman, high solids transportation: Geho, valves: Delta/Isogate, Hydrocyclones: Cavex, Dewatering screens: Enduron, Linatex, the range of IsoDRY equipment (thickeners, filters, centrifuges) and dewatering pumps: Multiflo
1. Traditional thickening method; however, with a pre-feed cyclone. Cyclone overflow reports to the thickener whilst the underflow reports to a dewatering screen. The thickener underflow is combined with the dewatering screen product to create an overall higher solids concentration for final disposal. This method reduces the loading on the thickener and improves the overall disposal solids content albeit using the commonly used thickening method. Transport to tailings storage where coarse material is used to build the dam walls and the overflow reports to the pond for future recovery.
2. Paste thickener with pipeline transportation, automation of the complete system to guarantee the highest solid content.
3. Centrifuge versus chamber filter press for truck disposal and TSF reduction. Our customer requires a material dry enough to be truck transported; the target dry solid content is 70%. A low-priced Capex is an critical driver. Decanter centrifuge is a better choice when compared to a low-pressure chamber filter press. It can produce a cake dry enough for truck transportation, compete on the CAPEX side, be lower on OPEX and accept the variation of underflow density of the manual thickener.
4. High pressure filter press for highest possible dryness and reduced install power.