Texture and bubble size measurements for modelling concentrate grade in flotation froth systems

dc.contributor.advisorBradshaw, Deeen_ZA
dc.contributor.advisorDe Jager, Gerharden_ZA
dc.contributor.advisorNicolls, Freden_ZA
dc.contributor.authorForbes, Gordonen_ZA
dc.date.accessioned2014-11-05T17:33:42Z
dc.date.available2014-11-05T17:33:42Z
dc.date.issued2007en_ZA
dc.descriptionIncludes bibliographical references (p. 237-244).en_ZA
dc.description.abstractNumerous, machine vision systems for froth flotation have been developed over the last ten years; however, there are many aspects of the systems, that still require further development before they become one of the standard instruments present on industrial flotation operations. This thesis aims to address these problems by developing improved measurement techniques and showing how these measurements can be used to model the concentrate grad e of the flotation cell being monitored in a manner which is, directly usable by plant personnel. This thesis, presents an improvement to the watershed algorithm for the measurement of bubble sixe distribution in flotation froths. Unlike the standard watershed algorithm, it is able to measure accurate bubble size distributions when both large and tiny bubbles are present in a flotation froth image. Flotation froths with “dynamic bubble size distribution s” are introduced and methods of reducing the high dimensional bubble size distribution data associated with them are discussed. A method of using characteristic histograms of frequently occurring bubble size distributions is introduced and shown to be an appropriate method to use. A number of standard texture measures are best suited to the classification of flotation froth images. Results show that the Fourier ring and texture spectrum based features, perform well whilst having a relatively small computational cost for classifying new images. Video footage from selected industrial operations has been used for the development of improved algorithms for the measurement of froth surface descriptors. Analyses of the relationship, between froth velocity, bubble size, froth class and concentrate grade are made. The results show that it possible to use a unified approach to model the concentrate grade, irrespective of the site on which the measurements are made. Results from three industrial case studies show that bubble size and texture measures can be used to identify froth classes. Furthermore the combination of froth classes and froth velocity information is shown to consistently account for the most variation in the data when the concentrate grade is modelled using a linear combination of these two measurements.en_ZA
dc.identifier.apacitationForbes, G. (2007). <i>Texture and bubble size measurements for modelling concentrate grade in flotation froth systems</i>. (Thesis). University of Cape Town ,Faculty of Engineering & the Built Environment ,Department of Chemical Engineering. Retrieved from http://hdl.handle.net/11427/9247en_ZA
dc.identifier.chicagocitationForbes, Gordon. <i>"Texture and bubble size measurements for modelling concentrate grade in flotation froth systems."</i> Thesis., University of Cape Town ,Faculty of Engineering & the Built Environment ,Department of Chemical Engineering, 2007. http://hdl.handle.net/11427/9247en_ZA
dc.identifier.citationForbes, G. 2007. Texture and bubble size measurements for modelling concentrate grade in flotation froth systems. University of Cape Town.en_ZA
dc.identifier.ris TY - Thesis / Dissertation AU - Forbes, Gordon AB - Numerous, machine vision systems for froth flotation have been developed over the last ten years; however, there are many aspects of the systems, that still require further development before they become one of the standard instruments present on industrial flotation operations. This thesis aims to address these problems by developing improved measurement techniques and showing how these measurements can be used to model the concentrate grad e of the flotation cell being monitored in a manner which is, directly usable by plant personnel. This thesis, presents an improvement to the watershed algorithm for the measurement of bubble sixe distribution in flotation froths. Unlike the standard watershed algorithm, it is able to measure accurate bubble size distributions when both large and tiny bubbles are present in a flotation froth image. Flotation froths with “dynamic bubble size distribution s” are introduced and methods of reducing the high dimensional bubble size distribution data associated with them are discussed. A method of using characteristic histograms of frequently occurring bubble size distributions is introduced and shown to be an appropriate method to use. A number of standard texture measures are best suited to the classification of flotation froth images. Results show that the Fourier ring and texture spectrum based features, perform well whilst having a relatively small computational cost for classifying new images. Video footage from selected industrial operations has been used for the development of improved algorithms for the measurement of froth surface descriptors. Analyses of the relationship, between froth velocity, bubble size, froth class and concentrate grade are made. The results show that it possible to use a unified approach to model the concentrate grade, irrespective of the site on which the measurements are made. Results from three industrial case studies show that bubble size and texture measures can be used to identify froth classes. Furthermore the combination of froth classes and froth velocity information is shown to consistently account for the most variation in the data when the concentrate grade is modelled using a linear combination of these two measurements. DA - 2007 DB - OpenUCT DP - University of Cape Town LK - https://open.uct.ac.za PB - University of Cape Town PY - 2007 T1 - Texture and bubble size measurements for modelling concentrate grade in flotation froth systems TI - Texture and bubble size measurements for modelling concentrate grade in flotation froth systems UR - http://hdl.handle.net/11427/9247 ER - en_ZA
dc.identifier.urihttp://hdl.handle.net/11427/9247
dc.identifier.vancouvercitationForbes G. Texture and bubble size measurements for modelling concentrate grade in flotation froth systems. [Thesis]. University of Cape Town ,Faculty of Engineering & the Built Environment ,Department of Chemical Engineering, 2007 [cited yyyy month dd]. Available from: http://hdl.handle.net/11427/9247en_ZA
dc.language.isoengen_ZA
dc.publisher.departmentDepartment of Chemical Engineeringen_ZA
dc.publisher.facultyFaculty of Engineering and the Built Environment
dc.publisher.institutionUniversity of Cape Town
dc.subject.otherChemical Engineeringen_ZA
dc.titleTexture and bubble size measurements for modelling concentrate grade in flotation froth systemsen_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
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