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Investigation of submerged trommel screen
Thesis (MEng)--Stellenbosch University, 2022.
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| Format: | Thesis |
| Language: | en_ZA |
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Stellenbosch : Stellenbosch University
2022
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| _version_ | 1867613864852455424 |
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| access_status_str | Open Access |
| author | Laker, Chris James |
| author2 | Akdogan, Guven |
| author_browse | Akdogan, Guven Laker, Chris James |
| author_facet | Akdogan, Guven Laker, Chris James |
| author_sort | Laker, Chris James |
| collection | Thesis |
| dc_rights_str_mv | Stellenbosch University |
| description | Thesis (MEng)--Stellenbosch University, 2022. |
| format | Thesis |
| id | oai:scholar.sun.ac.za:10019.1/124918 |
| institution | Stellenbosch University (South Africa) |
| language | en_ZA |
| last_indexed | 2026-06-10T12:42:55.322Z |
| license_str | Other — see source repository |
| provenance_str_mv | Harvested via OAI-PMH from SUNScholar — Stellenbosch University Repository |
| publishDate | 2022 |
| publishDateRange | 2022 |
| publishDateSort | 2022 |
| publisher | Stellenbosch : Stellenbosch University |
| publisherStr | Stellenbosch : Stellenbosch University |
| record_format | dspace |
| source_str | SUNScholar — Stellenbosch University Repository |
| spelling | oai:scholar.sun.ac.za:10019.1/124918 Investigation of submerged trommel screen Laker, Chris James Akdogan, Guven Bradshaw, Steven Martin Stellenbosch University. Faculty of Engineering. Dept. of Process Engineering. Screens (Mining) Trommel screen Mining engineering Shale shakers Separation (Technology) UCTD Thesis (MEng)--Stellenbosch University, 2022. ENGLISH SUMMARY: Trommels are investigated as an alternative to drain and rinse vibrating screens for the purpose of dense medium recovery. Iron ore and cyclone 40 atomized ferrosilicon were used to test screen performance on a submerged washing trommel. This trommel consists of two types of chambers, one for medium drainage and two submerged wash chambers to wash adhering medium. The performance of the drain chamber was evaluated with overflow properties such as moisture content, FeSi content and FeSi carryover, by varying medium relative density (RD) between 2.7 and 3.6. The results were compared to past studies on a vibrating drain and rinse screen by Kabondo (2018). The test work was performed on two separate trommel designs, Submerged DMS Trommel (Mk1) and Trommel Mk2. Due to design limitations in the design of Mk1, there was great uncertainty in the results from the first investigation. Mk1’s performance was however highly promising compared to vibrating drain screens. Percentage moisture in the overflow of Mk1 had a maximum of 3.60 % at a medium RD of 3.6, while vibrating screen results ranged between 10.29 % and 27.91 % at lower medium RDs below 2.3. % FeSi in the overflow of the drain chamber of Mk1 ranged between 11.05 % and 18.76 %, while the vibrating screen ranged between 9.71 % and 36.01 %. % FeSi carryover on Mk1 reached a maximum of 4.96 % while the vibrating screen ranged between 3.12 % and 10.46 %. In addition to competitive drainage of trommel Mk1, batch tests performed in the submerged wash chambers of Mk1, combined with bench tests for submerged washing and rinsing, concluded that the most effective washing method was motion of particles within a submerged bath. Efficiency for submerged washing ranged from 84.82 % to 99.7 %, compared to 74.24 % for rinsing of medium. It was justified to design a new test trommel, Mk2, from the learnings of the first campaign. The second trommel (Mk2) was designed with nine different underflow discharges. For the first time in open literature, trommel Mk2 provided insight into material distribution and utilised screen area of a trommel by evaluating these discharges. It was found that 98 % of drainage occurs through the middle and towards the direction of rotation of the trommel. The work on trommel Mk2 was performed at similar operating conditions as Mk1. The results of Mk2 had higher repeatability and statistical significance. Confidence was provided in the results and it was concluded that trommels is a competitive alternative to vibrating drain and rinse screens. Future work will include test work on all remaining operating parameters to develop a complete understanding how these parameters govern the operation of trommels. AFRIKAANS SUMMARY: Draaisiwwe word ondersoek as ’n alternatief tot drein en afspoel vibrerende skerms vir die doel van digte medium herwinning. Ystererts en sikloon 40 geatomiseerde ferrosilikon is gebruik om skermdoeltreffendheid op onderdompelde wasdraaisiwwe te toets. Hierdie draaisiwwe bestaan uit twee tipes kamers, een vir medium dreinering en twee onderdompelde waskamers om aanklewende medium te was. Die doeltreffendheid van die dreinkamer is geëvalueer met oorvloei eienskappe soos voginhoud, FeSi-inhoud en oorgedraagde FeSi, deur medium relatiewe digtheid (RD) te varieer tussen 2.7 en 3.6. Die resultate is vergelyk met vorige studies van vibrerende drein- en afspoelskerms deur Kabondo (2018). Die toetswerk is uitgevoer op twee aparte draaisifontwerpe, Onderdompelde DMS Draaisif (Mk1) en Draaisif Mk2. As gevolg van ontwerpbeperkinge in die ontwerp van Mk1, was daar groot onsekerheid in die resultate van die eerste ondersoek. Mk1 se doeltreffendheid was egter hoogs belowend in vergelyking met vibrerende dreinskerms. Persentasie vog in die oorvloei van Mk1 het ’n maksimum van 3.60% by ’n medium RD van 3.6, terwyl vibrerende skerm-resultate tussen 10.29% en 27.91% by laer medium RDe onder 2.3 gestrek het. %FeSi in die oorvloei van die dreinkamer van Mk1 het tussen 11.05% en 18.76% gestrek terwyl vibrerende skerms tussen 9.71% en 36.01% gestrek het. Oorgedraagde %FeSi op Mk1 het ’n maksimum van 4.96% bereik terwyl die vibrerende skerm tussen 3.12% en 10.46% gestrek het. Buiten ’n kompeterende dreinering van draaisif Mk1, het lottoetse uitgevoer in die onderdompelde waskamers van Mk1, gekombineer met banktoetse vir onderdompelde was en afspoel, tot die gevolg gelei dat die mees effektiewe wasmetode beweging van partikels binne ’n onderdompelde bad was. Doeltreffendheid vir onderdompelde was het tussen 84.82% tot 99.7% gestrek, in vergelyking met 74.24% vir afspoel van medium. Dit is geregverdig om ’n nuwe toetsdraaisif te ontwerp, Mk2, uit wat geleer is van die eerste veldtog. Die tweede draaisif (Mk2) is ontwerp met nege verskillende ondervloei uitstromings. Vir die eerste keer in oop literatuur, het Mk2 insig verskaf oor materiaalverspreiding en gebruikte skermarea van ’n draaisif deur hierdie uitstromings te evalueer. Dit is gevind dat 98% van dreinering plaasvind deur die middel en in die rigting van die rotasie van die draaisif. Die werk op draaisif Mk2 is uitgevoer by soortgelyke bedryfskondisies as Mk1. Die resultate van Mk2 het hoër herhaalbaarheid en statistiese beduidendheid gehad. Vertroue in die resultate is verskaf en daar is tot die gevolgtrekking gekom dat draaisiwwe ’n kompeterende alternatief tot vibrerende dreinering- en afspoelskerms is. Toekomstige werk sal toetswerk insluit op alle oorblywende bedryfsparameters om ’n volledige verstaan te ontwikkel van hoe hierdie parameters die bedryf van draaisiwwe beïnvloed. Masters 2022-03-09T08:52:14Z 2022-04-29T09:41:05Z 2022-03-09T08:52:14Z 2022-04-29T09:41:05Z 2022-04 Thesis http://hdl.handle.net/10019.1/124918 en_ZA Stellenbosch University xxiii, 180 pages : illustrations application/pdf Stellenbosch : Stellenbosch University |
| spellingShingle | Screens (Mining) Trommel screen Mining engineering Shale shakers Separation (Technology) UCTD Laker, Chris James Investigation of submerged trommel screen |
| title | Investigation of submerged trommel screen |
| title_full | Investigation of submerged trommel screen |
| title_fullStr | Investigation of submerged trommel screen |
| title_full_unstemmed | Investigation of submerged trommel screen |
| title_short | Investigation of submerged trommel screen |
| title_sort | investigation of submerged trommel screen |
| topic | Screens (Mining) Trommel screen Mining engineering Shale shakers Separation (Technology) UCTD |
| url | http://hdl.handle.net/10019.1/124918 |
| work_keys_str_mv | AT lakerchrisjames investigationofsubmergedtrommelscreen |