Characteristics and Challenges of Ultralight Powders
Powders such as carbon black, silica, or fine pigments are defined by their high air retention and low particle mass, which make them particularly difficult to handle in industrial packaging environments. Their bulk densities typically range between 10 and 350 g/l, and they often have fine particle sizes under 200 µm. These characteristics result in a strong tendency to generate airborne dust during the filling process, which can compromise both cleanliness and worker safety.
In addition, such powders are often sensitive to contamination or product loss, meaning even minor dust emissions or inaccuracies in dosing can lead to significant quality or efficiency issues. Conventional filling systems frequently struggle to maintain control over these materials, resulting in oversized packaging, unstable pallet loads, and elevated operational costs.
When filled using conventional systems, these materials often result in over dimensioned bags, low filling accuracy, and inconsistent palletization. Moreover, dust dispersion during filling contributes to cleaning costs and safety risks.
Vacuum-Based Filling: Functional Principle
With GREIF-VELOX’s vacuum system VeloVac, powders with grain sizes below 200 micrometres and bulk densities between 10 and 450 g/l are filled in a completely sealed vacuum chamber. Unlike pump-based systems, the VeloVac XL creates an atmospheric vacuum that draws the product directly into the FIBC — completely spill-free. Any dust that escapes is automatically extracted and reintegrated into the process, ensuring clean and efficient bagging.
This method results in:
- Significant reduction in filled bag volume, with compaction rates up to 400%
- Reduced logistics and storage costs thanks to higher product density per bag and optimized pallet utilization
- Dust-free handling, both within the machine and downstream on pallets
- Improved fill accuracy, supported by integrated weighing systems
- Lower product loss, due to minimal airborne material during the cycle
By addressing both product behaviour and process constraints, vacuum-based systems enable more consistent and space-efficient packaging of ultralight powders. The VeloVac system — available for both valve bags and FIBCs (as the VeloVac XL) — offers several key features that contribute to clean and efficient packaging:
- High filling accuracy, achieved through calibrated gross weighing
- Effective dust containment, enabled by the vacuum chamber and a sealed bag interface
- Lower energy consumption and operating costs thanks to the integration of the Greif-Velox DryVac dry-running pump which is up to 70% more efficient than conventional water ring pumps
- Integrated nozzle cleaning with the PureVacSpout, a movable suction unit that cleans the fill point between cycles without interrupting the process
Volume Reduction and Its Operational Impacts The most direct technical benefit of vacuum-based filling is the reduction of bulk volume per filled bag. In practice, this results in:
- Smaller bag sizes for the same net weight
- Increased pallet density, enabling more product per shipment
- More stable load units, with improved stack ability
- Reduced storage requirements, both in interim storage and at the customer site
According to internal studies, users of the VeloVac system have achieved up to 75% reduction in logistics and storage costs by replacing oversized bags with compacted formats. These savings are complemented by lower packaging material consumption and reduced CO₂ emissions per unit of product transported.
Workplace Safety and Cleanliness
Airborne dust during filling processes can pose health and safety risks, particularly in the chemical and food sectors. The VeloVac’s vacuum chamber prevents overpressure escape during filling and eliminates the need for manual dust extraction.
As a result of the vacuum-based filling process, pallets and bags remain clean, which significantly reduces the frequency and effort required for cleaning in production areas. Operator exposure to airborne dust is minimized, enhancing workplace safety and protecting employee health. In addition, the system helps to reduce both general contamination and cross-contamination risks, particularly important in sensitive production environments. Collectively, these factors contribute to a safer, more stable operating environment and help ensure ongoing regulatory compliance.
Simplified Investment in Vacuum Bagging with “Packaging as a Service (PaaS)”
To increase accessibility and align with customer investment cycles, Greif-Velox offers the VeloVac system through a Packaging as a Service (PaaS) model. Under this approach, the complete packaging solution is provided without the need for upfront capital investment. The service includes machine provision and flexible financing, along with ongoing maintenance and technical support to ensure reliable operation. It also covers the supply of wear and spare parts, as well as procurement of compatible bags and consumables, tailored to the specific application. All components are bundled into a single monthly rate, which can be scaled according to usage or production volume. This model enables companies to implement advanced packaging technology with full cost transparency and stable performance throughout the equipment’s lifecycle. It is particularly suited to facilities managing variable product lines or those aiming to reduce capital asset risk.
Efficient Handling of Ultralight Powders
Vacuum-based packaging systems such as the VeloVac provide an effective response to the logistical and operational challenges of handling ultralight powders. By enabling bulk volume reduction at the source, these systems improve transport efficiency, workplace safety, and product integrity.
