Bulk bags:
Reusable FIBC unloading for powder handling
What's in the guide
1. Introduction
The efficient unloading of bulk bags is critical for maintaining consistent production flow. This is especially true for powder handling applications. This guide examines the key components and considerations for engineers and integrators implementing reusable flexible intermediate bulk containers (FIBCs) unloading systems.
With modular designs and proven configurations, modern reusable FIBC unloading systems can be tailored to handle applications ranging from food-grade materials to abrasive or explosive powders. This guide is part three of a 3-part series to help you select and implement the right bulk bag unloading solution for your process. The series covers intermediate bulk containers (IBCs), disposable FIBCs and reusable FIBCs and their various methods, components, and considerations.
2. What are reusable FIBCs?
Reusable FIBCs, also known as bulk bags or big bags, are industrial fabric containers designed for repeated use in transporting and handling dry bulk materials. Unlike single-trip bags, reusable FIBCs and rigid IBCs used in powder handling are constructed with more durable materials and reinforced features to withstand unloading multiple times across many processing cycles.
The operator lifts the FIBC into a bulk bag discharger using a forklift or a frame-mounted hoist. Once loaded, the reusable bags are untied and slowly emptied to the downstream process.
These reusable intermediate bulk containers are widely used across industries for handling powders and granular materials, offering advantages in terms of:
- Reduced material handling costs
- Lower environmental impact
- Improved dust containment
- Enhanced batch integrity
- Greater operational flexibility.
Features of reusable bulk bags
Reusable FIBCs incorporate several design features distinguishing them from single-trip bags:
- Reinforced lifting loops for repeated handling
- Durable construction materials resistant to wear and tear
- Enhanced stitching patterns for extended service life
- Specially designed spouts for reliable sealing
- Antistatic and conductive options for hazardous materials
- Food-grade materials for regulated industries.
3. Types of bulk bags and unloading considerations
Spout bottom bags
The most commonly specified type of reusable FIBC features a discharge spout located at the bottom, typically ranging from 300 mm to 600 mm in length. These bags offer several advantages:
- Controlled discharge: The spout allows for a more controlled release of the contents.
- Reusability: Spout bags are designed to be reused multiple times.
- Versatility: They can be used with various discharge systems, including forklifts and electric hoists.
- Enhanced dust collection system when used with integrated spout clamping systems
- Product protection: Many spout bags come with additional features like safety valves or flaps to prevent leakage.
- Direct integration with standardised unloading stations, such as the ones offered by Floveyor’s modular bulk bag unloading stations.
Design considerations for spout bags:
- Draw cord closures for basic applications
- Pneumatic pinch valve closures for partial discharge and resealing of bags
- Multi-tie systems for additional security
- Poly bag liners for increased containment and contamination prevention
- Spout diameter optimisation for material flow characteristics
- Reinforcement requirements based on material density
- Antistatic requirements for combustible powders
- Clean-break connections for food-grade applications
- UV protection for outdoor storage scenarios.
4. Big bag unloading system: Methods and equipment for emptying material
Decanting solutions for reusable bulk bag handling are an integral part of many bulk material delivery systems around the world.
Forklift-based solutions
Reusable bulk bag unloading stations are designed to safely and reliably unload multi-trip FIBCs. Structurally certified frames are preferred, as they are ergonomically designed for operator safety and comfort. In addition, integrated bag carriers allow the reusable bulk bags to be safely left in place during unloading.
There are several forklift options for bulk bag unloading.
No frame FIBC unloading
The most basic forklift solution lifts an FIBC and dispenses it straight into the hoppers of powder handling conveyors.
- No fixed frame required
- Minimal capital investment
- Limited, if any, dust containment
- Suitable for basic operations
No frame FIBC unloading presents a massive risk to operator safety. If a strap breaks or comes off a hook or forklift, anyone standing under the bag will be crushed. No one should ever work under an unsupported bag. A safety frame is required to prevent crush risks when operators are untying a bag spout.
Full frame configurations
Used for decanting standard FIBCs, this big bag unloader solution provides a complete support structure for your bulk material handling operation.
- Seamless integration with forklift, a fixed frame and a spout untying chamber
- Quick-connect dust control interfaces to minimise environmental contamination
- Modular platform configurations
- Adjustable to suit variable bag heights
- Can be configured to provide operator access to any of the four sides of the frame to untie the FIBC spout
- Multiple access points for maintenance
- Available in dual station configuration to maximise throughput.
- Upgrades include:
- Bridge breaking bag massagers
- Integrated lump breaker
- Vibratory tundish
- Bag spout shut-off valve.
No frame FIBC unloading presents a massive risk to operator safety. If a strap breaks or comes off a hook or forklift, anyone standing under the bag will be crushed. No one should ever work under an unsupported bag. A safety frame is required to prevent crush risks when operators are untying a bag spout.
Low-profile options (half frame systems)
Low-profile forklift frames are ideal in areas where there is restricted headroom or where the forklift has a short mast. The frame comes in two halves. The top half of the frame can be removed and loaded with an FIBC at ground level, minimising the height required.
- Forklift FIBC carrier frame
- Spout untying chamber
- Connection for dust extraction
- Upgrades available for integrated lump breaker and vibratory tundish.
Hoist-based systems
Hoist FIBC unloading stations eliminate the need for a forklift, featuring a monorail and electric chain hoist. The modular design of the hoist-based FIBC unloading system allows for additional accessories to be added when requirements change.
- Quick-access spout untying chamber
- Connection spigot for dust extraction to minimise plant contamination
- Hoist FIBC carrier frame
- Popular upgrades include:
- Bridge-breaking bag massagers
- Integrated lump breaker
- Vibratory tundish
- Bag spout shut-off valve.
Advantages for hoist-based FIBC unloading systems include:
- Precise bag positioning
- Reduced manual handling
- Enhanced safety features
- Integration with automated systems.
5. Spout handling and containment
Spout clamping systems
Bag spout clamping provides a dust-tight seal that won’t leak or release during discharge and is best for high hygiene applications. A spigot is provided for connection to site dust extraction. Spout clamping systems are critical for controlled discharge:
- Secure material containment
- Dust-free operation
- Quick connection/disconnection
- Operator safety features.
Enclosed untying chambers
An untying chamber provides quick access to a dust-tight access door for operator ease and safety. A spigot is provided for connection to site dust extraction. Untying chambers deliver enhanced containment:
- Complete dust control
- Protected operator environment
- Clean-in-place capabilities
- Regulatory compliance features.
The drawback to enclosed untying chambers is the internal parts of the chamber collect residue. When the door is opened, some spillage may occur.
Shut-off valve integration
A manual or pneumatic pinch shut-off valve is used to close a partial bag, or in the instance of a breakdown, provides the ability to close-off the bag and avoid product spillage. The valve may be locked at various increments from fully open to fully closed. A shut-off value enables flow control capabilities, including:
- Emergency shut-off capability
- Batch process control
- Maintenance access
- Limited material flow regulation.
The drawback to enclosed untying chambers is the internal parts of the chamber collect residue. When the door is opened, some spillage may occur.
6. Accessories and components for a bulk bag unloading station
Material conditioning for unloading reusable FIBCs
Bulk bag conditioner
Bags that have been stored for extended periods often require conditioning aids to promote flow and ensure material discharges reliably. For example, hygroscopic materials in FIBCs may agglomerate and harden into large lumps. Bulk bag conditioners break down rock-hard material in bulk bags to the ideal size for integration into downstream equipment.
- 9,000 kg crushing force
- Safely and efficiently removes lumps and clumps
- 3-minute conditioning cycles
- Comes in manual or fully automated options.
Bag massaging paddles
Bag massaging paddles are used to break up minor lumps and promote flow and encourage materials to flow more efficiently. The paddles are applied to the outside of the bag to promote discharge.
- Controlled agitation
- Preserve bag integrity
- Variable intensity
- Supports a streamlined production environment.
Rotary lump breaker
Manage material consistency to ensure uniform particle size for optimal processing. A slimline design mounts directly onto the outlet of the spout chamber.
- Breaks up agglomerates
- Maintains flow
- Protects downstream equipment
- Conditions hazardous materials safely and without contamination
- Handles a wide variety of bulk materials
- Ideal for conditioning lumps for FIBC unloading to within AMC tolerances.
Dosing and weighing
Load cells: Bulk bag dischargers can be supplemented with analogue output load cells to provide accurate dosing and/or batching.
Dosing screw feeder (DSF): Designed to meter bulk materials into a Floveyor aero-mechanical conveyor (AMC). A variable-speed drive and close clearance solid-flight auger enable accurate metering and dosing of materials. When paired with a Floveyor reusable FIBC unloader that is equipped with load cells and a control system, it provides an accurate loss-in-weight formulation system.
Trough screw feeder (TSF): The Floveyor trough screw feeder is best suited to applications requiring a feeder capable of metering bulk material from a number of different sources into a single discharge. The modular design enables loading from FIBCs as well as direct connection to upstream process.
Advantages include:
- Works with multiple materials
- Accepts multiple material inlets
- Accepts multiple material sources
- Handles large lumps and provides optional lump breaking
- High cleanability with quick-access options available
- Economical solution for straight-line conveying and feeding.
Storage FIBC screw feeder (FSF)
The large, fully enclosed hoppers of Floveyor’s FIBC unloading screw feeders allow each bulk bag to be completely emptied in one go, freeing up the forklift during unloading. Plant and operator safety can be improved by using optional dust extraction devices. The equipment is engineered to be discharged directly into a Floveyor AMC. Other advantages include:
- Accepts multiple material inlets
- Accepts multiple material sources
- Handles large lumps and provides optional lump breaking
- High cleanability with quick-access options available
- Economical solution for straight-line conveying and feeding.
Material handling control
Storage solutions
FIBC unloading screw feeder (FSF) systems provide:
- Controlled material discharge
- Integrated screw feeding technology
- Precise flow rate control
- Efficient transfer to downstream processes
- Optional storage capacity
- Modular design for various configurations
- Integration with dust control systems
- Handling of powders with multiple material characteristics.
7. Integration with other screw feeders
If your process doesn’t require the bulk bag to be fully emptied into the hopper in one go, alternative screw feeders such as aero-mechanical screw feeders, dosing screw feeders and trough screw feeders provide accurate modulation of material flow through the use of a variable speed drive.
Screw feeder advantages include:
- High throughputs
- High availability
- Optimal for batching
- Accepts cohesive materials
- Accepts multiple materials.
8. Integration with conveying systems
Once materials are conditioned, they can be dispensed directly into a conveyor system. A conveyor paired with a Floveyor integrated FIBC unloader is one of the most effective and reliable solutions for getting your bulk materials into the plant and introduced safely and efficiently in your process line.
Tubular drag conveying (TDC)
Reusable bulk bag unloading can integrate with TDCs for controlled conveying across multiple planes at slow speed to handle multiple outlets. The fully enclosed system and rope assembly are designed for industries requiring a more stringent level of cleanliness and safety in bulk material handling.
Advantages in using a TDC for reusable bulk bag unloading:
- Gentle material handling
- Multiple feed points
- Dust-free operation
- Complex routing.
Aero-mechanical conveying (AMC)
Reusable FIBCs may feed directly into a Floveyor AMC via a hopper with integrated flow control. This can be combined alternatively with a first discharge into a screw feeder for precise, variable-speed metering of the bulk materials. When a Floveyor AMC and reusable FIBC unloader are paired, the seamless integration of equipment provides optimal bulk material handling for powders and granules.
Advantages to using an AMC in FIBC unloading:
- High throughputs
- Efficient transfers
- Minimal maintenance
- Easy cleaning
- Total batch transfers
- Flexible installation due to modular design
- Energy-efficient powder handling.
Case study: reusable bulk bag unloading systems
Food processing example
Wimmers, an Australian soft drink company, sought to upgrade its bulk sugar conveying system to support production expansion. Previously reliant on inefficient, labour-intensive forklift handling, they needed a faster, cleaner, and more precise solution. Floveyor provided a forklift bulk bag unloading system with a two-way diverter for seamless sugar distribution. A lump breaker prevented blockages in humid conditions, and safety interlocks enabled easy maintenance. Installed within three months, the system optimised flow, reduced downtime, and improved efficiency, helping Wimmers scale production while maintaining the quality of their premium soft drinks.
Read more: Floveyor conveying system for bulk sugar distribution
Chemical processing example
KLEN International, a global manufacturer of fire assay flux and geochemical consumables, required a robust conveyor system to handle diverse materials with minimal downtime. Floveyor provided a cost-effective solution by integrating existing bulk bag unloaders with new aero-mechanical conveyors, and a tubular drag conveyor. The upgraded system reduces wear, minimises residue, and allows quick cleaning and product changeovers. KLEN’s product team has praised the system’s efficiency and reliability, noting that it has improved operations and is expected to deliver a full return on investment within 12 months.
Read more: A robust bulk bag system for fire assay consumables manufacturer
Conclusion
Investing in a Floveyor reusable bulk bag unloading system offers advantages for powder handling operations. The modular design ensures organisations can start with a basic configuration and expand capabilities as needs evolve, protecting their initial investment while maintaining operational flexibility. In addition, the machinery and equipment fit together seamlessly, offering the best ergonomic and operating experience.
Floveyor’s proven expertise in powder handling solutions prioritise operator safety, dust control, and material integrity. The seamless integration between bulk bag unloading stations and Floveyor’s conveying technologies creates a complete material handling system delivering reliable performance and total batch transfers.
Whether handling food-grade materials, abrasive powders, or explosive substances, Floveyor’s bulk bag unloading systems maintain operational efficiency and return a lower total cost of ownership. The combination of robust construction, precise material control, and flexible configuration options ensures optimal performance over the system’s lifetime. Our range of reusable FIBC unloaders have been developed over more than 65 years and provide operator-friendly solutions while upholding proven materials handling best practice.
Get in touch with Floveyor
Gain efficiency with Floveyor bulk bag unloading solutions. Optimise your bulk material handling, improve operator safety and reduce downtime. Contact us for more information, or get a quote.
