STACK SIZER

TM

Patented Technology

The highest capacity, most efficient, fine wet screening machine in the world

The Derrick Stack Sizer has redefined the concept of efficient, fine particle wet screening. Never before has one screening machine had such a high capacity in a minimal amount of floor space. Consisting of up to five individual screen decks positioned one above the other and operating in parallel, the Stack Sizer can be fitted with Derrick’s high capacity, long life, urethane screen surfaces. With this unique combination, fine wet screening becomes more practical than ever thought possible. Hundreds of Stack Sizers are currently operating at mineral processing plants worldwide and earning significant returns.

Patented derrick Stack Sizer™

Feed Box oPtional rePulP SyStemScreen deckSSuPer g® motorS

urethane ScreenS

Flo-divider™

•High open area, up to 45 percent, formaximum flow capacity

•Fullrangeofopeningsdowntosuperfine75microns (200 mesh)

•Uniquenon-blindingdesignforoptimum performance

•Long panel life minimizes operating andmaintenance costs

•Up to five decks stacked one above theother all operating in parallel resulting in high capacity while minimizing floor space requirements

•Easyaccessformaintenanceandservicingofscreen panels

•Quickpanelreplacement–allpanelsonone5-deckmachinecanbechangedinabout

30to40minutes

•Powered by Derrick Super G or Super G2high frequency vibrating motors

•Onepairof2.5hpmotorsprovidesauniformhigh frequency linear motion throughout the entire width and length of all screen decks

•Superioroversizeconveyance

•Sealed bearing system eliminates externallubricating system and reduces maintenance

•Uniformdistributionoffeedslurryacrosstheentire width of the screen

•Frontcoveriseasilyremovedformaintenanceand debris removal

•Various inlet pipe configurations dependingupon equipment layout requirements

•Rubber-linedforlonglife

•Anoptionalrepulpingsystemisavailableforapplications requiring maximum fines removal from the oversize

•Spray water is directed at rubber-linedrepulping troughs located between panels on each screen deck

•Oversize from the first panel is repulpedand screened again on the second panel for maximum screening efficiency

Wash Trough

Spray Water

Oversize

ScreenPanel

Undersize

•Provides even and representative feed flowto the Stack Sizer decks to ensure optimal separation efficiency

•Designed according to process and layoutrequirements

•Equipped with dart valves to isolate flow toone or more distribution points

• Increase mill capacity and production rate

• Reduce power consumption per ton

• Minimize overgrinding of valuable minerals, improving the performance of downstream processes and increasing grade and/or recovery

• Concept proven in numerous worldwide mining operations

COPPERFour 5-deck Stack Sizers outfitted with 300 micron panels processing 520 t/h, replacing hydrocyclones as the classification device in a closed grinding circuit.

• Increased plant capacity throughput by 17 % • Reduced circulating load from 200% to 100% • Lower power consumption per ton • Consistent size distribution of undersize product

COALOne 5-deck Stack Sizer providing 100 micron separation on 41 t/h of clean coal spiral discharge replaced two large sieve bends and gave:

• Reduction in ash content from 20% to less than 10 % which doubled the product value • Decreased maintenance costs from replaced sieve bends • Reduced wear and maintenance costs of downstream screen bowl centrifuges

PHOSPHATEFour 5-deck Stack Sizers fitted with 390 micron urethane panels replaced hydrocyclones in a ball mill circuit.

• Production rate increased 40% to 50%

• Power consumption per ton decreased by 25% to 30%

• Circulating load reduced from 325% to less than 100%

• Improved product quality

SILICA SANDReplacement of two large hydraulic classifiers with two 5-deck Stack Sizers making a 0.5 mm separation on 240 t/h resulted in:

• Classification efficiency improved from 70% to over 90% increasing product recovery

• 87% reduction in process water, decreasing operating cost

• Accurate control of final product particle size

improved classification in grinding circuits

replacement of two large static screens

replacement of two Hydraulic classifiers

Stack Sizer caSe StudieS

New Feed

Oversize

Undersize

Pump

CircuitProduct

DerrickStack Sizer

Ball Mill

PrinciPle of oPeration

OperatiOn, Features, and beneFits

The patented Derrick Stack Sizer consists of up to five individual screen decks positioned one above the other and operating in parallel. A custom-engineered single or multiple stage Flo-Divider system representatively splits the feed slurry to each Stack Sizer and then to the decks on each machine. Ample space is provided between each of the screen decks for easy observation during operation and easy access for maintenance and replacement of screen surfaces. Each screen deck has an undersize collection pan which discharges to a launder with a single outlet. Similarly, the oversize from each of the screen decks collects in a single hopper with a common outlet.

5 - Way Flo-Divider

Easy AccessBetween Decks

UndersizeCollection Launder

Feed Box

Dual Vibrating Motors for Linear Motion

Undersize CollectionPans Under Eachof 5 Screen Decks

OversizeUndersize

features and benefits

• High capacity saves floor space and installation costs

• High separation efficiency increases product quality, reduces variability and improves downstream processes

• Linear motion produces superior screening efficiency and maximum oversize conveyance

• Low dynamic load minimizes structural requirements

• Low operating and maintenance costs

• Easy to service

• Durable high quality construction

WorldWide stack sizer applications

590 Duke Road • Buffalo, New York 14225 USA Phone: (716) 683-9010 • Fax: (716) 683-4991

E-mail: info@derrickcorp.com • www.derrickcorp.com

StackSizer - 9/08 Copyright ©2008 Derrick Corporation. / All products indicated by trademark symbols are trademarked and/or registered by Derrick Corporation

Single Deck Double Deck Triple Deck Four Deck Five Deck

Aluminum Dross

Bauxite

Chromium Ore

Coal

Colombium

Copper

Feldspar

Phosphate Installation in Morocco

Phosphate Installation in Russia

Iron Ore Installation in China

Iron Ore Installation in Brazil

Ferberite

Garnet

Gypsum

Iron Ore

Kaolin

Lead and Zinc

Mineral Sands

Silica Sand

Tantulum/Niobium

Tin Ore

Titanium

Tungsten Ore

Uranium

Nitrates

Phosphates

Platinum

Potash

Rare Earth Minerals

Resin Pellets

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