Matches in SemOpenAlex for { <https://semopenalex.org/work/W2247267106> ?p ?o ?g. }
Showing items 1 to 83 of
83
with 100 items per page.
- W2247267106 abstract "nnnnn Dense medium cyclones are widely used separating devices fornthe washing of plus 0.5mm coal. As approximately fifty percent ofnAustralian coal is washed in these devices, efficient cyclone operation isnobviously important.n n nnnnn Optimization of dense medium cyclone circuits requires annappreciation and understanding of both cyclone operation and commonnoperating difficulties. Examination of the literature showed that littlenmaterial has been published addressing such problems. The principalnreason for this shortcoming was that the traditional float and sinknanalysis for the determination of density separator performance wasnboth expensive and time consuming.n nnnnn A survey indicated that the use of density tracers was the mostnpromising alternative technique, although existing density tracersnwere not made to sufficiently rigorous specific gravity specifications tonaccurately define coal washing dense medium cyclone partition curves.n nnnnn The statistics of the density tracer process were analysed,nresulting in the selection of appropriaten i.nnnn specific gravity increment sizes, andn ii.nnn numbers of tracers per incrementn nnnnn to give results of the required accuracy when testing coalnwashing dense medium cyclone circuits. Appropriate data fittingntechniques were developed and tested for accuracy, and estimates of thenstandard deviation to be expected in tracer-derived partition data werencalculated.n n nnnnn A development programme resulted in the manufacture andntesting of tracers suitable for use at both the operating washery andnpilot plant level. The tracers were made to closer specific gravitynincrements, and more exacting specific gravity, tolerances, than tracersnpreviously used.n n nnnnnn The density tracers were tested in a number of Australiannwasheries, and techniques developed for the evaluation of circuitnperformance both under load and with the feed coal off. Partition datanderived from tracer and traditional float sink methods were compared,nand the tracer technique was shown to accurately define densitynseparator performance.nnnnnn In the course of the washery testwork, two areas of separationninefficiency were recognized.n nnnnnnnnnnn i.nnnnnnn Cyclone operation was unstable and inefficient when thencyclone was fed coal containing a large percentage ofnnear-gravity material, while being operated in such a manner that a large differential existed between thenoverflow and underflow medium specific gravities.n nnnnnnnnnn ii.nnnnnnn Overall dense medium cyclone circuit efficiency wasndecreased if the different modules were not separating atnidentical cutpoints. Cutpoint differences between modulesnwere found to be due to differing degrees of wear onncyclones and pumps, poor specific gravity control, andnmiscalibration of density gauges. Such problems werenfound at the majority of plants tested. n nnnnn The subsequent pilot plant testwork examined the effects ofncommon operating variables on separating efficiency. All variablesnwere found to affect either the cutpoint and separation efficiency ornthe specific gravity range of particle retention by their influence onnthe ' dynamic medium stability, as measured by the specific gravityndifferential. Regression analysis was used to develop a medium basednmodel of coarse coal dense medium cyclone separation, and thenseparation mechanism was explained in terms of this model.n n nnnnn Irregular and inefficient cyclone operation was found to benrelated to the magnitude of the specific gravity differential between thenoverflow and underflow medium specific gravities and the amount ofnretention-prone material in the cyclone feed. The retention pronenmaterial has a long residence time in the cyclone separating zone, andnif sufficient such material accumulates, then the flow pattern in thencyclone is temporarily disrupted. The specific gravity range ofnretention prone material was shown to increase as the specific gravityndifferential increased.n n nnnnn Efficient separation resulted from cyclone operation with lownspecific gravity differentials when treating coals containing moderatento high percentages of near gravity material. When treating coalsncontaining little near-gravity material, high specific gravityndifferentials can be tolerated since the feed contains little retentionnprone material.n n nnnnn Medium segregation was shown to be caused primarily bynclassification of the magnetite solids. This contrasts with high densitynore separations, where medium segregation results from bulknsedimentation of the medium. Areas of further work to fully implementna model of medium segregation are outlined.n" @default.
- W2247267106 created "2016-06-24" @default.
- W2247267106 creator A5045113635 @default.
- W2247267106 date "1987-01-01" @default.
- W2247267106 modified "2023-09-27" @default.
- W2247267106 title "A study of coal washing dense medium cyclones" @default.
- W2247267106 hasPublicationYear "1987" @default.
- W2247267106 type Work @default.
- W2247267106 sameAs 2247267106 @default.
- W2247267106 citedByCount "4" @default.
- W2247267106 crossrefType "journal-article" @default.
- W2247267106 hasAuthorship W2247267106A5045113635 @default.
- W2247267106 hasConcept C114614502 @default.
- W2247267106 hasConcept C121332964 @default.
- W2247267106 hasConcept C127413603 @default.
- W2247267106 hasConcept C153294291 @default.
- W2247267106 hasConcept C185544564 @default.
- W2247267106 hasConcept C185592680 @default.
- W2247267106 hasConcept C199289684 @default.
- W2247267106 hasConcept C201289731 @default.
- W2247267106 hasConcept C21880701 @default.
- W2247267106 hasConcept C2777864850 @default.
- W2247267106 hasConcept C2778863792 @default.
- W2247267106 hasConcept C33923547 @default.
- W2247267106 hasConcept C39432304 @default.
- W2247267106 hasConcept C41008148 @default.
- W2247267106 hasConcept C42812 @default.
- W2247267106 hasConcept C42935608 @default.
- W2247267106 hasConcept C43973154 @default.
- W2247267106 hasConcept C518851703 @default.
- W2247267106 hasConcept C548081761 @default.
- W2247267106 hasConcept C78519656 @default.
- W2247267106 hasConcept C93656029 @default.
- W2247267106 hasConcept C9390403 @default.
- W2247267106 hasConceptScore W2247267106C114614502 @default.
- W2247267106 hasConceptScore W2247267106C121332964 @default.
- W2247267106 hasConceptScore W2247267106C127413603 @default.
- W2247267106 hasConceptScore W2247267106C153294291 @default.
- W2247267106 hasConceptScore W2247267106C185544564 @default.
- W2247267106 hasConceptScore W2247267106C185592680 @default.
- W2247267106 hasConceptScore W2247267106C199289684 @default.
- W2247267106 hasConceptScore W2247267106C201289731 @default.
- W2247267106 hasConceptScore W2247267106C21880701 @default.
- W2247267106 hasConceptScore W2247267106C2777864850 @default.
- W2247267106 hasConceptScore W2247267106C2778863792 @default.
- W2247267106 hasConceptScore W2247267106C33923547 @default.
- W2247267106 hasConceptScore W2247267106C39432304 @default.
- W2247267106 hasConceptScore W2247267106C41008148 @default.
- W2247267106 hasConceptScore W2247267106C42812 @default.
- W2247267106 hasConceptScore W2247267106C42935608 @default.
- W2247267106 hasConceptScore W2247267106C43973154 @default.
- W2247267106 hasConceptScore W2247267106C518851703 @default.
- W2247267106 hasConceptScore W2247267106C548081761 @default.
- W2247267106 hasConceptScore W2247267106C78519656 @default.
- W2247267106 hasConceptScore W2247267106C93656029 @default.
- W2247267106 hasConceptScore W2247267106C9390403 @default.
- W2247267106 hasLocation W22472671061 @default.
- W2247267106 hasOpenAccess W2247267106 @default.
- W2247267106 hasPrimaryLocation W22472671061 @default.
- W2247267106 hasRelatedWork W111148337 @default.
- W2247267106 hasRelatedWork W1549809096 @default.
- W2247267106 hasRelatedWork W167299190 @default.
- W2247267106 hasRelatedWork W1969738772 @default.
- W2247267106 hasRelatedWork W1990614711 @default.
- W2247267106 hasRelatedWork W1991593474 @default.
- W2247267106 hasRelatedWork W1997531487 @default.
- W2247267106 hasRelatedWork W1998021645 @default.
- W2247267106 hasRelatedWork W2024294537 @default.
- W2247267106 hasRelatedWork W2025165943 @default.
- W2247267106 hasRelatedWork W2036549092 @default.
- W2247267106 hasRelatedWork W2058283489 @default.
- W2247267106 hasRelatedWork W2059375895 @default.
- W2247267106 hasRelatedWork W2061332532 @default.
- W2247267106 hasRelatedWork W2086866347 @default.
- W2247267106 hasRelatedWork W2147671455 @default.
- W2247267106 hasRelatedWork W2305636028 @default.
- W2247267106 hasRelatedWork W614549325 @default.
- W2247267106 hasRelatedWork W811734543 @default.
- W2247267106 hasRelatedWork W819145260 @default.
- W2247267106 isParatext "false" @default.
- W2247267106 isRetracted "false" @default.
- W2247267106 magId "2247267106" @default.
- W2247267106 workType "article" @default.