Thesis (MScEng)--University of Stellenbosch, 2002. / ENGLISH ABSTRACT: Flotation was introduced early in the zo" century as a separation process for
extracting valuable minerals from grinded ore. Today flotation is a dominant mineral
concentration method and is used for almost all sulphide minerals and also for nonsulphide
metallic minerals, industrial minerals, and coal.
Automation and control has become a basic requirement in flotation plants. Effective
control of pulp levels plays a very important role in stabilising the flotation process
and therefore requires careful attention.
This thesis presents a de-coupled level controller that has been developed for the
control of levels in cascaded flow processes, including multi-tank cascaded flotation
processes. The controller was developed on a two tank cascaded pilot plant using
water as a flow medium. A simulation model was constructed for the cascaded flow
process. The simulation model made it possible to develop and evaluate a decoupled
level controller in a simulation environment. Finally independent loop PIO
control and integrated PIO control loops with feed-forward de-coupling were
compared through simulation, as control strategies for the pilot plant. / AFRIKAANSE OPSOMMING: Flotasie is vroeg in die 20ste eeu bekend gestel as 'n skeidingsproses om
waardevolle minerale te onttrek uit fyngemaalde erts. Vandag is flotasie die
dominante proses om minerale te konsentrasie en word gebruik vir byna aile sulfied
minerale sowel as nie-sulfied metaal minerale, industriele minerale and steenkool.
Outomatisasie en beheer het 'n basiese vereiste geword in flotasie aanlegte. Die
effektiewe beheer van pulpvlakke speel 'n baie belangrike rol in die stabilisering van
die flotasie proses en verdien om hierdie rede deeglike aandag.
Hierdie tesis stel 'n ontkoppelde vlakbeheerstelsel voor wat ontwikkel is vir die
beheer van vlakke in kaskade vloei prosesse byvoorbeeld multi-tenk flotasie
prosesse. Die beheerstelsel is ontwikkel op 'n twee-tenk kaskade toetsaanleg met
water as vloeimedium. 'n Volledige simulasiemodel is ontwikkel wat dit moontlik
gemaak het om die vlakbeheerstelsel te ontwerp, toets en verfyn in 'n simulasie
omgewing. Verder is die verskil tussen onafhanklike enkellus PID beheerders en
ontkoppelde PID beheerlusse ondersoek en word in die tesis geillustreer.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:sun/oai:scholar.sun.ac.za:10019.1/52629 |
| Date | 03 1900 |
| Creators | Van Heerden, Jacobus P. (Jacobus Petrus) |
| Contributors | Du Plessis, J. J., Stellenbosch University. Faculty of Engineering. Dept. of Mechanical and Mechatronic Engineering. |
| Publisher | Stellenbosch : Stellenbosch University |
| Source Sets | South African National ETD Portal |
| Language | en_ZA |
| Detected Language | English |
| Type | Thesis |
| Format | 137 leaves : ill. |
| Rights | Stellenbosch University |
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