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Optimization of the energy distribution of SABC circuits

Gong D., Nadolski S., Sun C., Klein B., Kou J.

Physicochemical Problems of Mineral Processing

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2018

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Vol. 54, iss. 4

1245--1252

EN

Improving the energy efficiency of large grinding mills is of great importance to reduce the energy cost of mineral processing. The ratio of SAG mill to ball mill’s energy consumption varies greatly among SABC operations. Thus far, very few research studies have been conducted to demonstrate how the SAG mill or ball mill responses to the change of circuit energy distribution in terms of comminution efficiency. The present study investigated the energy performance of an operating SABC circuit at variable circuit energy distributions. An energy benchmarking model was used to assess the comminution energy efficiency of SAG mill, ball mill, and overall circuit. It is found that the target SABC circuit achieves the highest overall energy efficiency when 37.6% of the total circuit energy is distributed to the SAG mill and 62.4% to the ball mill. The maximum energy efficiency of this SABC circuit is approximately 25% when compared to the minimum practical energy required to carry out an equivalent comminution duty. The study also showed that the ball mill is more sensitive to the variation in circuit energy distribution than the SAG mill.

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The use of continuous centrifugal gravity concentration in grinding circuit. Modified approach for improved metallurgical performance and reduced grinding requirements

Altun N. E., Sakuhuni G., Klein B.

Physicochemical Problems of Mineral Processing

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2015

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Vol. 51, iss. 1

115--126

EN

The use of centrifugal gravity concentration in the closed-grinding circuit of a gold-containing massive sulphide ore was tested on classifier underflow and overflow. A continuous Knelson CVD6 was retrofitted to the hydrocyclone underflow for recovery of Au and Pb at a coarser feed size. The objective of treatment of overflow was recovering unliberated Au prior to flotation. The tests were performed in actual operating conditions at Nyrstar’s Myra Falls Mine. The results of the tests on the cyclone underflow revealed that both liberated and unliberated Au and Pb were recovered by the Centrifugal Variable Discharge (CVD) concentrator. Concentrate grades <60g/Mg Au were attainable at a more than 20% recovery. This application also allowed early and increased Pb recovery before it became gravity unrecoverable by over-grinding. Other benefits included capturing middlings for regrinding as well as potential coarser grinding and increase in mill throughput. A coarse grind also corresponds to a reduction in deformation of Au-particles, and is beneficial for increased Au recovery in downstream processing. Treatment of cyclone overflow by the CVD also provided favourable results. The outcomes included capturing unliberated gold prior to flotation and potentially reducing pumping requirements and reagent consumption. A comparison of the metallurgical performances showed that CVD application on classifier underflow was more effective. The CVD was capable of recovering unliberated gold in sulphides and performed better at a coarser particle size. Therefore, when used with the grinding circuit, a coarser grind can be applied and the CVD could be used to reject gangue at a coarser size.

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Upgrading valuable mineralization and rejecting magnesium silicates by pre-concentration of mafic ores

Altun N. E., Weatherwax T., Klein B.

Physicochemical Problems of Mineral Processing

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2014

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Vol. 50, iss. 1

203--215

EN

Amenability of mafic ores to pre-concentration was investigated with respect to ore mineraliza-tion characteristics. For the pre-concentration tests seven ores from various nickel-copper operations at Sudbury, Ontario were subjected to dense medium separation. Size assays of metal values, i.e. distribution of nickel and copper with respect to size fractions, were also determined. The ores were assessed in three categories of valuable mineralization as massive pure sulphides, coarse massive sulphide grains and disseminated sulphides. For ores with massive pure sulphides and coarse massive sulphide grains even a size classification based pre-concentration route could be sought since a clear trend of metal enrichment was identified towards finer fractions. Orebodies of similar mineralogy had similar responses to pre-concentration tests. The best results were for those ore bodies with a distinct differentiation between mineralization and gangue, i.e. the ores with massive pure sulphides, where nickel recoveries of 97% and mass rejections of 38-53% were achieved. Similar results were obtained for ores with coarse massive sulphides. For disseminated sulphide mineralogy relatively lower mass rejection was attained with acceptable recoveries of metals. Rejection of magnesium bearing gangue, such as talc, was identified as another benefit of pre-concentration. The extent of magnesium rejection occurred as a function of ore mineralogy. Clear distinction between valuable mineralization and gangue provided preferential magnesium rejection at high levels with no or minor metal losses.

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MECHATRON Nowoczesny System Dozowania Materiałów Sypkich

Klein B.

Pomiary Automatyka Robotyka

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2001

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R. 5, nr 1

36-37

PL

W wielu procesach przemysłowych bardzo ważne jest dokładne i stabilne podawanie materiałów sypkich pomimo ich różnych właściwości przepływowych. Bardzo często jakość produktu końcowego oraz koszt jego wytworzenia zależą w dużym stopniu od zastosowanych urządzeń.

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MECHATRON - Nowoczesny System Dozowania Materiałów Sypkich

Klein B.

Napędy i Sterowanie

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2001

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R. 3, nr 1

54--55

PL

W wielu procesach przemysłowych bardzo ważne jest dokładne i stabilne podawanie materiałów sypkich pomimo ich różnych właściwości przepływowych. Bardzo często jakość produktu końcowego oraz koszt jego wytworzenia zależą w dużym stopniu od zastosowanych urządzeń dozujących. Wychodząc naprzeciw rosnącym wymaganiom technologicznym, firma Schenck opracowała rodzinę nowoczesnych urządzeń dozujących, zapewniających ciągłe podawanie materiałów sypkich. Dozownik Mechatron może pracować wolumetrycznie (objętościowo) i grawimetrycznie (masowo). Jeśli materiał ma stabilny ciężar usypowy, to podawanie wolumetryczne wymagające nastawienia jedynie określonej prędkości podajnika, może w wielu przypadkach dać zadowalające rezultaty przy stosunkowo niskich kosztach urządzenia.