Are there container mixers COM that can be coupled directly to drums or IBCs?
Yes. There are container mixers which have large openings and can be coupled directly to standardised transport and storage containers such as drums (for example 200 l steel or plastic drums) or IBCs. The container in question is itself used as the mixing chamber, so that no transfer into a separate mixing vessel is required.
Two forms have essentially become established:
- The mixing tool dips into the drum or container, homogenises the product and then travels back out again (typically up to sizes of approximately 4 m³).
- The drum is swivelled or inverted through approximately 180° so that the mixing tool can homogenise the mixes within the container; the system then swivels back into the starting position.
In both cases the ideally mixed product is present directly in the drum or container.
Technical implementation
Clamping, tensioning and reception systems
Special clamping arms, tensioning devices or cage or frame constructions fix the drum or IBC securely to the mixing unit. Depending on the system, hydraulic, pneumatic or mechanical clamping jaws are used which absorb the forces arising during mixing (torsion, tilting and tumbling movements).
Adapter and modular receptions
For different container geometries (round drums, square IBCs, differing heights), adapter plates, insert baskets or reducing inserts are used. They bridge differences in dimensions and ensure geometric compatibility with the standard reception of the mixer.
Movement kinematics
Common mixing principles are tumble and 3D mixing or rotation about an inclined axis. The container is moved as a whole, without an agitator tool dipping into the product. This enables intensive blending, often with a container position optimised for discharge.
Safety and equipment features
Closed protective enclosures, end position monitoring, balancing and imbalance control as well as optional ATEX-compliant designs are state of the art in applications with combustible dusts or solvents.
Process engineering advantages
- Avoidance of cross-contamination, since the product does not leave the original container.
- Reduced cleaning effort, because no product-contact stationary mixing vessels or permanently installed agitator elements have to be cleaned.
- Low-dust or dust-free handling, particularly with toxic or heavily dusting powders, since the system remains closed during mixing.
- High traceability, since every batch remains in its associated container.
- An integrated process chain, because the same container can be used for transport, storage, mixing and subsequent dosing or filling steps.
- Suitability for demanding products, for example dust-sensitive, hygroscopic or GMP-relevant powders in pharmaceuticals, fine chemistry and the food industry.
Requirements and limits
Mechanical stability of the container
The drum or IBC must be designed for the dynamic loads of the mixing operation (rotation, tumbling movement, acceleration forces). With plastic IBCs, a corresponding approval of the container is required.
Tightness
Lid and clamping ring systems must close in a dust- and liquid-tight manner in order to avoid leakage during movement.
Permissible total weight
The gross weight of the filled container (including adapter) must lie within the load capacity of the mixing drive, lifting and clamping device.
Geometric compatibility
The dimensions of the container must fit within the working range of the reception or clamping systems in order to ensure central alignment and a stable path of the centre of gravity.
Fill level
The usable fill level typically lies at 40–70 % of the container volume, so that sufficient free volume is available for circulation of the mix and thus for an efficient mixing action.
Yes – this is how amixon® couples the container mixer COM directly to containers and IBCs
amixon® manufactures three types of container mixing plant: (a) the COM system, (b) the AM system and (c) the EM system.
a) COM: the container is the mixing chamber
This concept can be realised up to batch sizes of 4 m³.
With the amixon® container mixer COM, the bulk material container itself serves as the mixing vessel. The SinConcave®/SinConvex®-MultiPlane® helical ribbon mixing tool is introduced into the product from above, the container is closed gas-tight and the mixing operation is carried out directly within the container. The mixing tool then travels slowly out of the mix in reverse operation; the container is removed and the finished mixed product remains inside it.
Dimensionally accurate Mixtainer® units serve as standard mixing vessels. The container thereby becomes the dosing, mixing, transport and holding vessel for filling machines, extruders or liquid preparation, and the mixing process fits directly into an IBC-based production logistics.
Precision mixing instead of tumbling
Unlike tumble or rotation mixers, in which the container is moved as a whole, the COM works with a chamber-controlling helical mixing tool. Component compositions with mass ratios of up to 1 : 100,000 can thereby be homogenised in a technically ideal manner, even with widely differing bulk densities, particle sizes and with the involvement of liquid or moist components. Cutting rotors and liquid addition directly within the effective range of the cutting rotors are optionally available. The three-dimensional total flow (upwards at the periphery, downwards in the centre) achieves high mixing qualities even at a low fill level – in mixing operation without a cutting rotor a minimum fill level of about 15 % is sufficient, with the cutting rotor switched on it should be at least 60 %; the mixing chamber can be designed for ATEX Zone 20 applications.
Decoupled production and hygiene
A container mixer supports decoupled order production: weighing in, mixing and filling take place in separate areas. While one zone is being set up or cleaned, production continues in other zones, a considerable gain in capacity with frequently changing recipes. A Washtainer® can be docked for automatic wet cleaning and drying of the mixing tool. On request the plants meet EHEDG, FDA and 3-A Sanitary standards; typical sizes lie between approximately 100 and 4,000 litres.
b) Excursus: conical mixer AM 1500 with container filling and discharge
This system works with inexpensive standard bulk material containers. Owing to small filling and discharge connections, the system works almost free of dust.
The amixon® conical mixer size AM 1500 uses standard bulk material containers for filling and discharge. The following process steps can thereby be decoupled in time and space:
- Batching and weighing in of the raw materials in the inexpensive standard container (IBC)
- Mixing in the conical mixer
- Discharge into the same standard container or another one
- Cleaning of mixer, containers and filling machine
Batching can therefore take place, for example, while the mixer is still being cleaned, and filling can run while the mixer is already processing the next order. Waiting times are minimised and plant performance rises.
Where the room height is limited, the AM 1500 is guided on the wall by a lifting and lowering system: the mixer travels down for filling, the container is placed on the filling connection above, the product flows in, the fitting closes and the mixing operation starts. After mixing, the apparatus travels up again, an empty container is positioned below, the discharge fitting opens, and the bulk material flows out almost completely. Alternatively, discharge into big bags, sacks or a filling machine movable on rails is possible. Large inspection doors enable ergonomic cleaning; dry and wet cleaning regimes can be implemented within a few minutes.
Compared with the special containers of classic container mixers, standard bulk material containers are inexpensive and can be held in greater numbers. This avoids the availability of containers becoming a bottleneck in production planning.
c) EM: mixing directly in the standard drum
For small batches in the standard drum, amixon® offers the single-shaft mixer EM with a usable volume of approximately 5 to 200 litres. The mixing chamber rotates for filling and discharge, and a hand pallet truck, scales and standard drums suffice as infrastructure. The concept is suitable for small productions, premixes and just-in-time mixing orders.
Which combination of COM, AM conical mixer and EM is the most economical solution is clarified by amixon® together with the operator in pilot-plant trials with the original product.