MechChem Africa March-April 2022

⎪ Minerals processing and materials handling ⎪

Flexicon’s new BULK-OUT ® BFC Bulk Bag Discharging System promotes the flow of bulk solid materials that have solidified during storage and shipment, automati- callydischarging thematerialwhileallowing manual additions of ingredients fromsacks, drums and other containers. Acantilevered I-beamwith electric hoist and trolley lowers a bag lifting frame to floor level for rapid attachment of the bag to patented Z-CLIP™ bag strap holders. It then hoists and rolls the bag into the safety frame, eliminating the need for a forklift. The integral conditioner consists of two hydraulically-actuated rams with specially contoured conditioning plates that press opposing sides of the bulk bag. A Human- Machine-Interface (HMI) housed inaNEMA 4 (IP 56) enclosure controls the stroke and number of ramactuations. Theelectric hoist can be used to raise and lower the bag for conditioning at varying heights. For bulk bag discharging, the bag outlet spout is pulled through an iris valvemount- ed on top of the dust hood over the hopper. Once the bag outlet is secured and the iris valve is closed, the bag spout drawstrings can be untied, the dust-tight, snap-action access door closed, and the valve slowly released, reducing uncontrolled bursts of material into the hopper and dust into the plant environment. Formanual dumping in conjunctionwith, or independent of, bulk bag discharging, the operator raises the hinged door and adds the material from smaller capacity was able to remove gangue minerals and reduce the volume of bulk material before being treated by the WHIMS. “Another benefit of this process was that about a third of the material sent to the WHIMS in this process could be returned to the spiral circuit for further upgrade to meet specifications,” he notes. “This considerably reduces tailings vol- umes, potentially cutting down the foot- print of the tailings storage facility and extending its lifespan.” Bornman says that the cost of managing tailings facilities in a compliant manner, and the tightening regulations and policies on tailings dams, are encouraging a trend to re-process them. Technology improve- ments in metal recovery over the years now makes these re-treatment efforts commercially attractive. “We have had considerable success

Manganese stockpile material was tested using the Multotec UX7 ultra-fine spiral concentrator for roughing and scavenging phases, and the Multotec SC21 five-turn spiral for the cleaning phase.

in applying the spirals together with the WHIMS, as it is key to ensure sufficient bulk reduction up front,” he says. “The process can be applied across a range of

commodities, and we have also seen good results in minerals including chrome, iron ore, lithium and mineral sands.” www.multotec.com

Bulk bag discharger with integral conditioner and bag dump station

less steel finished to industrial, food, dairy or pharmaceutical standards. Flexicon also manufactures other con- figurations of bulk bag dischargers, bulk bag conditioners, and bag dump stations aswell as flexible screw conveyors, tubular cable conveyors, pneumatic conveying systems, bulkbagfillers, drum/box/container tippers, drum fillers, weigh batching and blending systems, and engineered plant-wide bulk handling systems with automated controls. www.flexicon.co.za

containers through a coarse screen into the hopper. A fold-down support tray serves as a bag rest. Thehopper canbe configured toconnect to pneumatic or mechanical conveyors, or directly todownstreamprocess equipment. The discharger can also be configured for weigh batch discharging with the addition of load cells and a programmable controller. Models are available in carbon steel with durable industrial coating with stainless steel material-contact points, or in all stain-

Flexicon’s BULK-OUT ® BFC Bulk Bag Discharger with integral Bulk Bag Conditioner and Bag Dump Station conditions materials prone to solidifying during shipment or storage.

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