What advantages does a conical mixing dryer with reactor function offer for moisture-sensitive formulations?
A cone mixer-dryer with a reactor function combines mixing, reacting and drying in a closed system. For moisture-sensitive formulations this offers above all effective protection against atmospheric humidity, oxidation, contamination and product losses, together with high process reliability and good product quality.
The most important advantages at a glance
A closed, hermetic process system
Processing takes place without transfer between several apparatus. Contact with atmospheric moisture is thereby minimised, which is particularly important with hygroscopic, water-reactive or oxidation-sensitive substances.
Inerting and vacuum operation
The process space can be inerted with protective gases such as nitrogen or argon and operated under vacuum. This enables drying at lower temperatures through boiling point reduction, protects thermolabile active substances and reduces hydrolysis and oxidation reactions.
Gentle and homogeneous blending
The conical vessel design and the wall-scraping mixing tool ensure efficient and uniform blending. This is important in order to avoid agglomerates and to achieve a reproducible distribution of active ingredients and excipients.
Efficient heat transfer
The double-walled cone geometry offers a large heat transfer area. In combination with vacuum, moisture can be removed particularly efficiently without loading the product thermally more than necessary.
A one-pot process with fewer interfaces
Depending on the application, several process steps can be combined in one apparatus, for example reaction, neutralisation, solvent exchange, crystallisation and drying. This reduces handling steps, process time, cleaning effort and the risk of faulty batches.
Low and reproducible residual moisture
Through precise control of vacuum, temperature, agitator and drying time, very low residual moisture values can be achieved. This is decisive where even small moisture contents influence stability, storage life or further processing.
Good product protection and low contamination
The mechanical loading is usually lower than with strongly shearing processes. At the same time, a design with few dead spaces and good emptiability supports the purity of the batch and reduces product build-up.
Safe handling of solvents
Vapours drawn off can be condensed and recovered. This makes economic sense and at the same time increases process and environmental safety, particularly with volatile or hazardous solvents.
High process and plant flexibility
Cone mixer-dryers with a reactor function can be adapted to different product quantities and requirements. They are therefore suitable for pharmaceutical active substances, fine chemicals, speciality chemicals and other demanding formulations.
How amixon® selects the right vacuum mixer-dryer or conical reactor
The selection criteria
Decisive are the required batch size range, the fill level window, the discharge requirement, the temperature sensitivity of the product, the rheological behaviour during drying, hygiene and sterility requirements as well as the available installation space. Both amixon® series – the cone mixer-dryer reactor AMT and the vertical mixer-dryer/reactor VMT – are pressure-tight and vacuum-tight down to 5 mbar abs., fully temperature-controllable via water, steam or thermal oil and designed for ATEX Zone 20 including the mixing tool.
When the cone reactor is the right choice
The conical geometry of the AMT guides the product completely to the central ball segment valve. Free-flowing mixes can be discharged almost without residue, which is particularly advantageous with valuable active substances and frequent product changes. Low fill levels, from approximately 15 %, can also be realised reliably. The dryer is readily accessible from above, quick to clean and, on request, steam-sterilisable.
When the vertical apparatus is the right choice
With its cubic vessel proportions, the VMT uses the available installation space particularly efficiently and is therefore suitable for large batches. The standard size range extends to 40,000 litres; in total, 100 to 50,000 litres in 100-litre increments can be realised. On request, amixon® also manufactures low-profile or slim geometries for limited installation heights or floor areas. The vapour filter with a lateral inspection door as well as the optionally lateral or upper manway facilitate access and cleaning.
For temperature-sensitive products
Both apparatus dry particularly quickly and gently at low temperatures and low rotational frequencies. This is also relevant for sensitive products such as fungal spores, bacterial cultures or effect pigments. Large heat transfer surfaces, in particular the temperature-controlled mixing tool, shorten the drying time. A cutting rotor can bridge tough plastic phases. The final choice of apparatus is secured at amixon® in a pilot plant trial with the original product under real temperature and pressure conditions.
Qualifiable and documented
For regulated environments, amixon® supplies qualifiable plants. Every apparatus is a one-off in accordance with the URS and is manufactured with quality control that has no gaps. amixon® assists on request with DQ, IQ and OQ; documentation and execution follow, on request, EU GMP and FDA 21 CFR Part 11. On request, the mixers additionally meet requirements in accordance with EHEDG, the FDA hygiene guidelines, the 3-A Sanitary Standards, USDA, GMP, ATEX and ASME and are integrated into the operator's validation concept from the start of the project through to commissioning.
Engineering and manufacture in Paderborn
amixon® develops and manufactures exclusively at the Paderborn works with a high depth of manufacture and predominantly German components. As a certified welding company with European, Japanese, Korean and American qualifications, every apparatus is designed as a one-off on the basis of the operator's URS. Complete in-house manufacture and quality control secure long-term supply and make later re-manufacture of components reproducibly possible.