The fracture and autogenous comminution of quartzite

Simple item page
dc.contributor.advisorBall, Anthonyen_ZA
dc.contributor.authorKanellopoulos, Achilles Constantineen_ZA
dc.date.accessioned2016-03-21T19:01:59Z
dc.date.available2016-03-21T19:01:59Z
dc.date.issued1978en_ZA
dc.descriptionBibliography: p.103-116.en_ZA
dc.description.abstractComminution is the process which aims at increasing the surface area and the resultant liberation of a particular constituent from the mass of a solid. The autogenous mill uses tumbling to effect comminution, but instead of special milling bodies being added, pebbles of the material to be comminuted are used. The autogenous comminution process utilises less than 0,1 per cent of the energy input. The principal objective of the present work was to analyse autogenous milling behaviour in terms of the individual comminuting mechanisms and to establish the inter-relationships between the main process variables, namely rock petrography, size distribution of the feed, applied load, relative velocity and environment. In this manner the optimisation of the process and an improvement of its efficiency was sought. In addition the establishment of testing procedures to predict the autogenous milling behaviour of a given type of rock was aimed. In the present work the gold bearing Witwatersrand quartzite was used, although the findings are applicable to other types of rocks. Since fracture phenomena are involved in all comminuting mechanisms of impact-compression, chipping and abrasion, slow compression and Brazilian tests were performed. The grain size and the mineral composition of the rock has been found to have a large influence on the local stresses required for these processes. Indeed the results show that the fragility and therefore ease of comminution increases with increasing grain size of the quartzite. Brazilian tests on drill cores of varying diameters may allow the prediction of the critical size of rock of the mill feed which can survive in a mill of given characteristics.en_ZA
dc.identifier.apacitationKanellopoulos, A. C. (1978). <i>The fracture and autogenous comminution of quartzite</i>. (Thesis). University of Cape Town ,Faculty of Engineering & the Built Environment ,Centre for Materials Engineering. Retrieved from http://hdl.handle.net/11427/18008en_ZA
dc.identifier.chicagocitationKanellopoulos, Achilles Constantine. <i>"The fracture and autogenous comminution of quartzite."</i> Thesis., University of Cape Town ,Faculty of Engineering & the Built Environment ,Centre for Materials Engineering, 1978. http://hdl.handle.net/11427/18008en_ZA
dc.identifier.citationKanellopoulos, A. 1978. The fracture and autogenous comminution of quartzite. University of Cape Town.en_ZA
dc.identifier.ris TY - Thesis / Dissertation AU - Kanellopoulos, Achilles Constantine AB - Comminution is the process which aims at increasing the surface area and the resultant liberation of a particular constituent from the mass of a solid. The autogenous mill uses tumbling to effect comminution, but instead of special milling bodies being added, pebbles of the material to be comminuted are used. The autogenous comminution process utilises less than 0,1 per cent of the energy input. The principal objective of the present work was to analyse autogenous milling behaviour in terms of the individual comminuting mechanisms and to establish the inter-relationships between the main process variables, namely rock petrography, size distribution of the feed, applied load, relative velocity and environment. In this manner the optimisation of the process and an improvement of its efficiency was sought. In addition the establishment of testing procedures to predict the autogenous milling behaviour of a given type of rock was aimed. In the present work the gold bearing Witwatersrand quartzite was used, although the findings are applicable to other types of rocks. Since fracture phenomena are involved in all comminuting mechanisms of impact-compression, chipping and abrasion, slow compression and Brazilian tests were performed. The grain size and the mineral composition of the rock has been found to have a large influence on the local stresses required for these processes. Indeed the results show that the fragility and therefore ease of comminution increases with increasing grain size of the quartzite. Brazilian tests on drill cores of varying diameters may allow the prediction of the critical size of rock of the mill feed which can survive in a mill of given characteristics. DA - 1978 DB - OpenUCT DP - University of Cape Town LK - https://open.uct.ac.za PB - University of Cape Town PY - 1978 T1 - The fracture and autogenous comminution of quartzite TI - The fracture and autogenous comminution of quartzite UR - http://hdl.handle.net/11427/18008 ER - en_ZA
dc.identifier.urihttp://hdl.handle.net/11427/18008
dc.identifier.vancouvercitationKanellopoulos AC. The fracture and autogenous comminution of quartzite. [Thesis]. University of Cape Town ,Faculty of Engineering & the Built Environment ,Centre for Materials Engineering, 1978 [cited yyyy month dd]. Available from: http://hdl.handle.net/11427/18008en_ZA
dc.language.isoengen_ZA
dc.publisher.departmentCentre for Materials Engineeringen_ZA
dc.publisher.facultyFaculty of Engineering and the Built Environment
dc.publisher.institutionUniversity of Cape Town
dc.subject.otherMaterials Engineeringen_ZA
dc.titleThe fracture and autogenous comminution of quartziteen_ZA
dc.typeDoctoral Thesis
dc.type.qualificationlevelDoctoral
dc.type.qualificationnamePhDen_ZA
uct.type.filetypeText
uct.type.filetypeImage
uct.type.publicationResearchen_ZA
uct.type.resourceThesisen_ZA
Files
Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
thesis_ebe_1978_kanellopoulos_achilles_constantine.pdf
Size:
5.4 MB
Format:
Adobe Portable Document Format
Description:
Download
Collections
PhD / Doctoral