A. Roshdieh, K. Seddon, M. Mohebbi, K. Shakeri, M. Nosrati
{"title":"Dareh Alou thickened tailings management scheme: design considerations","authors":"A. Roshdieh, K. Seddon, M. Mohebbi, K. Shakeri, M. Nosrati","doi":"10.36487/ACG_REP/1910_03_ROSHDIEH","DOIUrl":"https://doi.org/10.36487/ACG_REP/1910_03_ROSHDIEH","url":null,"abstract":"This paper presents a case study on the design of a thickened tailings storage facility (TSF) for a proposed open pit copper mine at Dareh Alou, Iran. \u0000Dareh Alou mine is a new copper mine owned by National Iranian Copper Company (NICICO). It is located in the Kerman Province of the Islamic Republic of Iran. The nominal production rate is 7 Mtpa for a life-of-mine (LOM) of 25 years. Planning was undertaken for the accommodation of a total of 175 Mt of tailings. \u0000The Dareh Alou mine site is located on a sloping side of a valley that is surrounded by hills, grading up to steep mountainous terrain. Since this is a greenfield project the location of the concentrator was selected in conjunction with the tailings deposition options study. Five concentrator locations with various ore transportation options have been investigated together with the tailings and water management study. The result of the study indicated that the best concentrator plant location was at RL 3050 m at approximately 2.5 km from the preferred TSF location. \u0000Various tailings and water management options were evaluated, including high rate, high density/high compression, and paste thickeners. These dewatering options were studied alongside the combinations of various TSF and thickener locations. \u0000The outcome of the options study indicates that if the price of make-up water is not included in the analyses, the preferred option is utilisation of high rate thickeners. However, after inclusion of make-up water at a rate of USD 1/m3, the preferred option would be the utilisation of high density/high compression thickeners. In this case, the distance between the concentrator and the TSF is such that transportation of un-thickened tailings to thickeners located adjacent to the TSF is the most efficient option. Also, thickening the tailings will provide benefits in reducing the embankment construction cost even though relatively large embankments will be required to close off the valley site.","PeriodicalId":20480,"journal":{"name":"Proceedings of the 22nd International Conference on Paste, Thickened and Filtered Tailings","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80179650","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Online rheology monitoring of a thickener underflow","authors":"AG Chryss, A Monch, K Constanti-Carey","doi":"10.36487/ACG_REP/1910_37_CHRYSS","DOIUrl":"https://doi.org/10.36487/ACG_REP/1910_37_CHRYSS","url":null,"abstract":"The perceived need for accurate and reliable methods of measuring suspension rheology in real time arises from the greater demands being placed on mineral processing operations. To extend mine life and reduce TSF footprint the adoption of finer grinds, higher solids concentration and high clay ores result in complex multiphase suspensions that need close monitoring to optimise thickener performance, pipeline transport and tailings deposition. Often the control of the processing or transport of these suspensions can be related to its rheology. However, due to the involved nature of rheological measurement for suspensions and the nuanced interpretation of data necessary to produce useful decisions, rheometry has only seen limited application in process monitoring. A robust unit that can measure, analyse and interpret the rheology of a process stream continuously and unattended is needed. The CSIRO has developed an online rheometer to address this problem. This paper describes the process prior to the deployment of the online rheometer to an Australian goldfield site, comparing online rheological measurement to benchmark laboratory values.","PeriodicalId":20480,"journal":{"name":"Proceedings of the 22nd International Conference on Paste, Thickened and Filtered Tailings","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76154443","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Severe service valves for applications with high percentages of solids","authors":"R. Waters","doi":"10.36487/ACG_REP/1910_42_WATERS","DOIUrl":"https://doi.org/10.36487/ACG_REP/1910_42_WATERS","url":null,"abstract":"The technology behind industrial applications such as fluids with high percentage solids continues to evolve, as do the corresponding regulations and specifications that ensure the safety of workers and the environment. Valves make up key aspects of this technology and often represent the single point of failure for entire operations. More often than not, the valves being used in high percentage solids applications are known as severe service valves (SSVs) due to their ability to withstand extreme conditions. Most experts agree that SSVs are identified by applications, and that these applications are challenging to the valve’s ability to provide a minimum acceptable level of performance over a minimum acceptable duration. This paper serves to determine what the minimum requirements are for SSVs in high percentage solids applications specifically concentrating on paste and thickened tailings.","PeriodicalId":20480,"journal":{"name":"Proceedings of the 22nd International Conference on Paste, Thickened and Filtered Tailings","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77938666","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
B. Salvoldi, Bernardt van der Spuy, Stephen E. Wilson
{"title":"Optimisation of cemented aggregate backfill at New Luika Gold Mine","authors":"B. Salvoldi, Bernardt van der Spuy, Stephen E. Wilson","doi":"10.36487/ACG_REP/1910_32_SALVOLDI","DOIUrl":"https://doi.org/10.36487/ACG_REP/1910_32_SALVOLDI","url":null,"abstract":"Cemented aggregate fill (CAF) and cemented rockfill (CRF) have successfully been used as a low-cost, highstrength backfill material in underground mines. The placement of the material and flowability generally limits the technology to low throughput application and smaller stope sizes if tight filling is required. \u0000Optimisation of CAF/CRF flowability and strengths is most readily achieved by optimising the Fuller–Thompson gradation curve. CAF/CRF relies on the materials available on the mine site and the additional costs of borrow pits or additional crushing adds significant cost to a material that is usually chosen due to low cost. \u0000This paper presents a case study of an optimisation of a CAF material by the addition of tailings in order to increase the paste fraction of the material. The main aim was to decrease the angle of repose to improve filling ability in addition to decreasing the required binder content.","PeriodicalId":20480,"journal":{"name":"Proceedings of the 22nd International Conference on Paste, Thickened and Filtered Tailings","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77945763","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Electrokinetic dewatering of mine tailings from hydrometallurgical processes","authors":"J. Q. Shang, Y. Xu","doi":"10.36487/ACG_REP/1910_18_SHANG","DOIUrl":"https://doi.org/10.36487/ACG_REP/1910_18_SHANG","url":null,"abstract":"Fine-grained tailings (leach residue and gypsum) resulting from hydrometallurgical processes (acid leach followed by lime neutralisation) of nickel laterite ores are proving difficult to dewater using conventional dewatering methods (thickeners/vacuum filters). To generate a dense non-segregating slurry or paste that can be deposited on surface in the form of a stable stack, more innovative dewatering methods are required. The current work involves working on thickened nickel laterite tailings to produce a paste product for surface disposal. Achieving greater dewatering would offer advantages compared to conventional slurry deposition such as reducing the size of impoundments; reducing the size and costs of containment dams; and decreasing water sent to the impoundment. It also offers environmental advantages, including reduced leachate generation and decreased permeability of paste (homogeneous mass). Electrokinetic (EK) consolidation is a soil improvement technique that has been mostly used for soft fine-grained soils, such as silts and clays. The treatment involves applying a direct current across electrodes embedded into the soil. The current induces the movement of soil–water from the anode (positive pole) toward the cathode (negative pole). Dewatering and consolidation are achieved when the water is permitted to drain at the cathode and prohibited to enter the anode. The electrochemical reactions are associated with the EK process, which leads to a pH gradient in soil, generation of hydrogen and oxygen gases at electrodes and corrosion of consumable anodes, which must be addressed on a project-specific basis. The objective of this research is to study the viability of using EK to dewater tailings (leach residue and gypsum) from hydrometallurgical processes. The electroosmotic (EO) flow rate and coefficient of EO permeability (ke) are measured to assess the effectiveness of EK dewatering. The study includes comprehensive material characterisation and EK cell tests. The results of the study indicate: \u0000EO generated significant water flow in the tailings sample. The tailings have stable electrical conductivity, i.e. the applied current can be maintained relatively constant over time under a constant voltage. The ke values are in the range of 1.00 × 10-9 to 7.00 × 10-9 m2/V/sec, which is considered very favourable for EO dewatering. \u0000The electric conductivities of the saturated tailings are in the range of 2,000–2,300 S/cm, and the tailings porewater has the electric conductivity of 8,000 S/cm, which is considered favourable in terms of power consumption for EK dewatering. \u0000The zeta potentials of the tailings before and after EO tests are stable in the pH range of 4–9, indicating EO dewatering would be effective in tailings without pre-treatment.","PeriodicalId":20480,"journal":{"name":"Proceedings of the 22nd International Conference on Paste, Thickened and Filtered Tailings","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85324785","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Adam Thomas, S. Edwards, J. Engels, H. McCormack, V. Hopkins, R. Holley
{"title":"Earth observation data and satellite InSAR for the remote monitoring of tailings storage facilities: a case study of Cadia Mine, Australia","authors":"Adam Thomas, S. Edwards, J. Engels, H. McCormack, V. Hopkins, R. Holley","doi":"10.36487/ACG_REP/1910_11_THOMAS","DOIUrl":"https://doi.org/10.36487/ACG_REP/1910_11_THOMAS","url":null,"abstract":"Tailings storage facilities (TSFs) are an essential infrastructure of mineral processing, but they represent a significant physical, chemical and biological hazard and must, therefore, be strictly and responsibly sited, managed and closed. Tailings can, for example, be dispersed by many processes (such as sinkholes, earthquakes, intense rainfall and flood events, and wind), substandard design and construction, and seepage. The stability and behaviour of TSFs needs to be continuously monitored and one highly effective way of doing this is through satellite Earth observation (EO). \u0000The EO industry is witnessing a technological revolution. Large and long-lifespan satellite sensors that have been the staple of national space agencies and commercial satellite manufacturers are now being complemented by constellations of low-cost, short-lifespan ‘cube sats’ by companies with the ambition to image the whole earth daily. Satellites with synthetic aperture radar (SAR) sensors are also collecting high volumes of data, with the added benefit of being able to do so day or night and in different weather conditions. The range of data options and capabilities these provide open opportunities for novel data analysis techniques for TSFs. One of these is satellite InSAR (interferometric SAR; a technique used to map millimetric-precision changes in ground height over time), which is already used by mining companies to reduce risk in and of their operations. From monitoring the stability of TSFs, through to assessments of impacts of natural hazards, InSAR allows rapid and accurate targeting of high-risk areas and structures to identify those that require subsequent investigation through ground-based methods. \u0000To demonstrate the application of EO data and InSAR in identifying pre- and post-failure mine activities and TSF deformation, the authors will present a case study across Cadia mine, New South Wales, Australia, which had a localised TSF failure on 9 March 2018. The InSAR results presented show that low-magnitude subsidence signals were observed across the TSF dam during the year preceding the collapse. In January 2018 a notable change in behaviour was observed, with a concentrated area of subsidence focused on the region which initially failed on 9 March 2018. Furthermore, post-collapse InSAR measurements show an increased rate of subsidence for regions either side of the failure zone. Review of medium- and high-resolution satellite images show that the failure was phased, with an initial failure and then a subsequent failure at least two days after 9 March 2018. It also highlights what might be construction activity associated with a dam raise prior to failure.","PeriodicalId":20480,"journal":{"name":"Proceedings of the 22nd International Conference on Paste, Thickened and Filtered Tailings","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90072284","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Paste reticulation blockage: an Australian case study","authors":"As Morcombe","doi":"10.36487/ACG_REP/1910_43_MORCOMBE","DOIUrl":"https://doi.org/10.36487/ACG_REP/1910_43_MORCOMBE","url":null,"abstract":"This paper looks at the design of a paste reticulation system, particularly a new method of diverting paste flows in critical situations, and the safeguards that were incorporated into the reticulation design to minimise the risk of line blockage during backfill operations. It also details the actions taken during a paste blockage event to flush and recover the entire line. \u0000The paper considers some of the restrictions that were imposed due to cost and time restraints on the schedule, and the impact these restrictions had on the profile and the flow characteristics of the reticulation network. Finally, a summary of key learnings and solutions that have been implemented to further safeguard the system has been provided.","PeriodicalId":20480,"journal":{"name":"Proceedings of the 22nd International Conference on Paste, Thickened and Filtered Tailings","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88802950","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Estimating the in situ state of a thickened tailings deposit","authors":"D. Reid","doi":"10.36487/ACG_REP/1910_02_REID","DOIUrl":"https://doi.org/10.36487/ACG_REP/1910_02_REID","url":null,"abstract":"Estimating the in situ state that will be achieved within a thickened tailings storage facility is often challenging, as laboratory-prepared specimens are known to not necessarily reproduce the fabric and density of the tailings when they settle under full-scale high energy deposition. Samples prepared in the laboratory from non-segregating slurries often result in quite dense states, which may not occur in full-scale deposition. Some of these issues were investigated during a recent geotechnical investigation of a thickened tailings deposit. The investigation consisted of cone penetration test (CPT) probes followed by piston samples at locations directly adjacent to the probes within saturated regions near the base of the tailings. The piston samples were used to estimate in situ density by means of gravimetric water content (GWC) of the entire sample, and to provide material for preparing loose, moist tamped, reconstituted samples for measuring the critical state line (CSL) of the recovered tailings. The resulting state indicated by comparing the in situ GWCs and the CSLs agreed well with that inferred by CPT-based methods, providing additional confidence in both techniques. A reconstituted sample prepared as a slurry in the lab exhibited a denser state than that indicated from in situ GWCs, raising questions about the accuracy of laboratory-prepared slurries for investigating the density likely to be achieved in situ.","PeriodicalId":20480,"journal":{"name":"Proceedings of the 22nd International Conference on Paste, Thickened and Filtered Tailings","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86695585","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Effects of the mineralogical composition and particle size distribution on the rheology of gold and copper tailings","authors":"P Desriviers, A. Quintero, P Primeau","doi":"10.36487/ACG_REP/1910_38_DESRIVIERS","DOIUrl":"https://doi.org/10.36487/ACG_REP/1910_38_DESRIVIERS","url":null,"abstract":"Globally there is an upward trend by mining operations to opt for tailings dewatering technologies to reduce water consumption, minimise surface disturbance (footprint), increase the stability of tailings deposits and, overall, to operate sustainably. \u0000The properties of the mine tailings are largely dictated by the type of ore and the process necessary to liberate the metal values. In other words, it depends on the beneficiation process and the mineralogy of the gangue. Due to the importance of selecting the correct strategy for the management of mine tailings, designing a disposal strategy based solely on the requirements of ore processing may overlook opportunities to maximise the viability of the mining operation, especially when dewatering technologies are being considered. As an example, accepting a coarser grind may reduce overall metal recovery; however, the loss in revenue may be offset by improved dewatering performance and lower capital and operating cost to manage the tailings. Therefore, the design of the ore beneficiation process should consider the requirements for tailings disposal, specifically tailings dewatering and storage facility design, in order to obtain more efficient and sustainable mining operations. \u0000This paper will discuss the effects of mineralogical composition and particle size distribution of gold and copper tailings on rheological properties, which provides an indication of what can be achieved in thickener underflows. The present paper is based on laboratory tests performed by Golder Associates on mine projects around the globe.","PeriodicalId":20480,"journal":{"name":"Proceedings of the 22nd International Conference on Paste, Thickened and Filtered Tailings","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86483616","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Development of centrifugal slurry pumps in tailings disposal and comparison with positive displacement pumps","authors":"J. Crawford, N. Bessett","doi":"10.36487/ACG_REP/1910_39_CRAWFORD","DOIUrl":"https://doi.org/10.36487/ACG_REP/1910_39_CRAWFORD","url":null,"abstract":"This paper covers FLSmidth KREBS® pump development, over the past 10 years, of an extensive range of highpressure centrifugal slurry pumps for multistage applications. The primary objective has been to produce safe, economical, energy efficient and maintenance friendly centrifugal slurry pumps to fulfil the expanding requirements of the mineral processing industries in the long distance transportation of tailings and mineral slurries. Two ranges of pumps have been developed, a double cased pump (based on the KREBS rubber lined slurryMAX™ XD pump) and an unlined white iron cased pump (based on the millMAX™ pump). \u0000The logic behind the development of the two pump ranges will be explained in depth covering the design and first article production, getting it right. The methodology of the hydraulic and structural criteria requirements that are considered during the pumps’ design are integrated with the use of computational fluid dynamics and finite element analysis to ensure that the pumps perform safely, reliably and with maximum efficiency. \u0000Application of the pumps to projected operating data is explained taking into consideration specific needs for flange and foundation loads, maintenance and condition monitoring. Consideration of slurry rheology and its implication on pumping performance is discussed. \u0000Cost comparison between actual field data and the theoretical positive displacement (PD) costs, as presented at the 21st International Seminar on Paste and Thickened Tailings, will be analysed in the Appendix.","PeriodicalId":20480,"journal":{"name":"Proceedings of the 22nd International Conference on Paste, Thickened and Filtered Tailings","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81285293","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}