{"title":"Study on the preparation and application of phenolic resin-based filling composite materials in coal mines","authors":"Yunfeng Zhang, Jinhua Wu, Xinyu Zhang, Jipeng Zhu","doi":"10.1080/25726668.2021.1891807","DOIUrl":"https://doi.org/10.1080/25726668.2021.1891807","url":null,"abstract":"ABSTRACT An in situ modification method is used to synthesize a new type of phenolic resin-based composite material used to fill goafs and seal air leaks in roadways. This was followed by scanning electron microscopy, oxygen index, and compression tests. The results show that when the aluminium hydroxide, Sd-31 silicone oil and methylene chloride are added to the phenolic resin in a mass fraction ratio of 8%:5%:3%, the overall performance of the composite material is the best. Compared with unmodified phenolic resin, the oxygen index and compressive strength of thecomposite material are increased by 40.16% and 3.5 times, respectively. The maximum reaction temperature of foaming and curing is also reduced from 120.3 to 87.2°C. To verify the performance of the new material, field tests were carried out at Matigou coal mine in Gansu, China. The average air leakage rate of the working face was reduced from 12.8 to 2.1 %.","PeriodicalId":44166,"journal":{"name":"Mining Technology-Transactions of the Institutions of Mining and Metallurgy","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2021-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77805331","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}
S. Islam, David J. Williams, Chenming Zhang, M. Llano-Serna
{"title":"Geotechnical characterisation of coal tailings down the beach and constant rate of loading consolidation in a slurry consolidometer","authors":"S. Islam, David J. Williams, Chenming Zhang, M. Llano-Serna","doi":"10.1080/25726668.2021.1880351","DOIUrl":"https://doi.org/10.1080/25726668.2021.1880351","url":null,"abstract":"ABSTRACT The conventional disposal of slurried tailings in a tailings storage facility (TSF) leads to the formation of a beach, on which the tailings sort hydraulically, settle, consolidate, and desiccate upon exposure. Basic geotechnical testing, such as specific gravity, Atterberg limits, and particle size distribution, found that there was no particular trend of changes in the tailings properties down the beach. The settled sediment found in a settling test was slurry-like and unsuitable for conventional oedometer testing. Constant rate of loading (CRL) consolidation testing is more representative of the continuous disposal of tailings slurry than conventional step loading. Consolidation testing in a slurry consolidometer was conducted and captured from a slurry-like to soil-like state. A slow rate of loading increased the test time, while a too quick rate of loading built up very high excess PWP. The test results showed different stages of consolidation, depending on excess PWP development and dissipation, and applied stress.","PeriodicalId":44166,"journal":{"name":"Mining Technology-Transactions of the Institutions of Mining and Metallurgy","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2021-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85942593","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":"Modification of orientation-dependency limitation for BQD index measured from exploratory drill cores in stone quarries (a case study)","authors":"Arman Hazrathosseini, Adel Taheri","doi":"10.1080/25726668.2021.1880352","DOIUrl":"https://doi.org/10.1080/25726668.2021.1880352","url":null,"abstract":"ABSTRACT Various indices, notably rock quality designation (RQD), weighted joint density (WJD), and block quality designation (BQD) have been introduced by researchers to survey joints in boreholes, each with its own advantages and disadvantages. The idea of combining WJD and BQD to use positive features of both formed the main goal of the current study, leading to the definition of an improved BQD . After joint surveys of cores drilled in Kulikosh Marble Quarry, Iran, linear regressions validated by statistical tests showed that BQD is less dependent on the drilling direction than the RQD. An empirical equation was also obtained as , with the help of which one can estimate the value of by measuring the original BQD . Taking into account the joint orientations, is logically closer to reality whereby mining engineers can assess block productivity of stone quarries more accurately.","PeriodicalId":44166,"journal":{"name":"Mining Technology-Transactions of the Institutions of Mining and Metallurgy","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2021-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75497399","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":"Catalogue of real-time instrumentation and monitoring techniques for tailings dams","authors":"Luke Clarkson, David J. Williams","doi":"10.1080/25726668.2021.1874094","DOIUrl":"https://doi.org/10.1080/25726668.2021.1874094","url":null,"abstract":"ABSTRACT With ongoing catastrophic mine tailings dam failures, the hindsight revelation of poor safety records, and an increasing prevalence of public scrutiny and attention of mining operations, there is an immediate call for enhanced safety of tailings dams. Today, challenges arise in identifying and utilising the ability of monitoring systems to understand the complex performance and behaviours of these dams, reflecting on the system’s ability to predict deterioration before failure occurs. New literature, mining regulators, insurance firms, and mining practitioners are calling for increased diligence in the form of real-time monitoring: but what can the industry offer in response? This research establishes a centralisation of real-time monitoring instruments suitable for tailings dams, discussing the specifications, advantages, and disadvantages of each. An understanding of traditional instrumentation, online monitoring systems, and the value of centralised monitoring was detailed. Collaboration with suppliers discovered innovative systems which enable monitoring of different failure modes and mechanisms.","PeriodicalId":44166,"journal":{"name":"Mining Technology-Transactions of the Institutions of Mining and Metallurgy","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2021-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85410623","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":"An efficient algorithm for the precedence constraint knapsack problem with reference to large-scale open-pit mining pushback design","authors":"Nayan Maiti, P. Pathak, B. Samanta","doi":"10.1080/25726668.2020.1866369","DOIUrl":"https://doi.org/10.1080/25726668.2020.1866369","url":null,"abstract":"ABSTRACT In this paper, a new Specific Breakpoint Algorithm (SBA), which can efficiently search appropriate breakpoints of parametric maximum-flow-related problems, is presented. The algorithm is used to solve Lagrangian Relaxed Precedence Constrained Knapsack Problem (LRPCKP) and Linear Programming Relaxed Precedence Constrained Knapsack Problem (LPRPCKP) in mine pushback design. The relaxed solutions are then processed through Rounded Topo-Sort (RoTS) heuristic to produce feasible solutions. The study results on seven bench mark datasets on Minelib for two approaches, referred here as LRPCKP-SBA and LPRPCKP-SBA, indicate that LRPCKP-SBA in spite of being faster, produces inferior quality solutions than well known BZ and CPLEX solutions. However, LPRPCKP-SBA produces a comparable quality of solutions as BZ in a computationally more efficient manner. Furthermore, the RoTS heuristics operated on relaxed solutions produce a better quality of feasible solutions than an existing technique, Expected Topo-Sort heuristic (ExTS).","PeriodicalId":44166,"journal":{"name":"Mining Technology-Transactions of the Institutions of Mining and Metallurgy","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2021-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82434216","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":"Impact of bulk density estimation in mine planning","authors":"Celso Reis, C. Arroyo, A. Curi, Marcelo Zangrandi","doi":"10.1080/25726668.2021.1876481","DOIUrl":"https://doi.org/10.1080/25726668.2021.1876481","url":null,"abstract":"ABSTRACT The incorporation of bulk density uncertainty for Mineral Resource and Mineral Reserves (MRMR) steps is of great importance for successful mine planning process. In practice, most mining projects use an average density value for each lithological type of the deposit. However, density determinations require special attention as they directly affect the conversion of volumes to tonnages and ore grades to metal contents. The objective of this study is to measure and minimize the risks associated with the MRMR stages, including the density variability in mine planning. Traditional interpolation techniques in geostatistics were used to represent density spatial distribution in a block model, similarly to those used for grade estimation. This approach was developed and applied at a Brazilian iron ore mine. The results indicate MRMR are underestimated if density uncertainty is not considered. Mine design changes were observed, including 5% impact on the Life-of-mine (LOM) and 2% in Net Present Value (NPV).","PeriodicalId":44166,"journal":{"name":"Mining Technology-Transactions of the Institutions of Mining and Metallurgy","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2021-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84798012","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":"Pre-ignition detection and early fire detection in mining vehicles","authors":"R. Hansen","doi":"10.1080/25726668.2021.1871820","DOIUrl":"https://doi.org/10.1080/25726668.2021.1871820","url":null,"abstract":"ABSTRACT With an increasing demand for early detection of mining vehicle fires, the question is how an early detection could be achieved? Data from cone calorimeter tests and incident summary data were applied when analysing possible fire detection solutions on mining vehicles. Based on the tests, pre-ignition and post-ignition solutions in the cab and the engine compartment were analysed and presented. If overcoming the challenges of the environment, smoke sensors could for example be a potential pre-ignition detector in engine compartments. Based on the incident summaries, clues on detectable traces, etc., were identified and a discussion on the types of sensors for various types of vehicles and sections was provided. Fires in for example the turbo/exhaust area and engine compartment, could be detected prior to ignition using gas sensors to detect the emitted hydrocarbons or an oil mist detection system.","PeriodicalId":44166,"journal":{"name":"Mining Technology-Transactions of the Institutions of Mining and Metallurgy","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2021-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73009598","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}
Shahrokh Paravarzar, H. Askari-Nasab, Y. Pourrahimian, X. Emery
{"title":"Simultaneous multi-sector block cave mine production scheduling considering operational uncertainties","authors":"Shahrokh Paravarzar, H. Askari-Nasab, Y. Pourrahimian, X. Emery","doi":"10.1080/25726668.2021.1872261","DOIUrl":"https://doi.org/10.1080/25726668.2021.1872261","url":null,"abstract":"ABSTRACT The main objective of this study is to provide a practical and near-optimal mine production schedule for block caving operations considering operational uncertainty. The problem is defined in the context of goal programming optimization to meet the operational objectives, including tonnage and grade as daily production targets. The considered operational constraints include drawpoints and ore pass design, draw rate, mine production, and transportation capacities in different operational levels, tonnage and grade constraints, and mine production targets in the presence of several mining sectors. The developed model is verified and validated using historical operational data obtained from an actual block caving operation. The practicality and flexibility of the framework are examined through three different operational scenarios and compared with the real block caving operation mine plans and historical production data.","PeriodicalId":44166,"journal":{"name":"Mining Technology-Transactions of the Institutions of Mining and Metallurgy","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2021-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85995423","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}
Luana Teixeira Pontara Lopes, Fernando Cesar Fernandes Junior, Edmo da Cunha Rodovalho, Thammiris Mohamad El Hajj
{"title":"Impact assessment of waste screening over the life of a Brazilian bauxite mining operation","authors":"Luana Teixeira Pontara Lopes, Fernando Cesar Fernandes Junior, Edmo da Cunha Rodovalho, Thammiris Mohamad El Hajj","doi":"10.1080/25726668.2020.1857156","DOIUrl":"https://doi.org/10.1080/25726668.2020.1857156","url":null,"abstract":"ABSTRACT The mining sector is looking for new technologies to minimise its environmental impacts and to maximise its reserves. The need to increase the life of mines has led to investigations considering the options to maximise Brazilian bauxite mine reserves. This work evaluates the use of a flip screen in the loader bucket to recover ore from the overburden. The study investigates both the financial and technical feasibilities of this option. This device results in a decrease in the amount of waste and an increase in the life of mine. An average mass recovery of 48% is achieved. The concentration of the bauxite present in the overburden is possible using only screening and the oversized (>12.7 mm) product contains 40% of the available alumina, with less than 4% reactive silica and 0.5% organic carbon, which is acceptable for the Bayer process.","PeriodicalId":44166,"journal":{"name":"Mining Technology-Transactions of the Institutions of Mining and Metallurgy","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2020-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77438690","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":"Digital hierarchical model of lumpiness of blasted rock mass","authors":"B. Rakishev, Z. Rakisheva, A. Auezova, A. Orynbay","doi":"10.1080/25726668.2020.1838775","DOIUrl":"https://doi.org/10.1080/25726668.2020.1838775","url":null,"abstract":"ABSTRACT The article describes the developed new digital hierarchical model of lumpiness of blasted rocks. It is based on a combination of classes of pieces of rock by size, taken as hierarchical levels of lumpiness of rocks, and the percentage of pieces in classes, adopted for its numerical characteristics. 7 classes of rocks by size are considered, each of which is characterized by the content of its pieces. The key component of the proposed model - the granulometric composition of the blasted rocks is determined by the block mass of the rocks, the size of the zones of intense crushing, the volume of crushed rocks due to the action of stress waves and reflected waves (I stage of explosion), detonation products (swelling effect of the explosion) (II stage of explosion), and collisions of large pieces when moving (III stage of explosion). The regularities of the formation of these explosion results are established depending on the different combination of the physicomechanical properties of the rocks of the massif, the chemophysical characteristics of the explosive used, the parameters of the explosives and the explosive method.","PeriodicalId":44166,"journal":{"name":"Mining Technology-Transactions of the Institutions of Mining and Metallurgy","volume":null,"pages":null},"PeriodicalIF":1.1,"publicationDate":"2020-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78749485","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}