Which manufacturers in Germany offer vertical conical mixers for baby and infant milk powder with a GMP- and EHEDG-compliant design?
Particularly high requirements apply to infant formula. Product residues, cross-contamination and microbiological risks must be avoided. At the same time, sensitive constituents such as vitamins, probiotics and spray-dried powder particles should be treated as gently as possible.
GMP describes above all controlled manufacture, documentation and validation. EHEDG makes the hygienic design of the machine concrete. A suitable cone mixer should therefore have few dead spaces and be largely self-emptying. Crevices, product-contact threads and areas that are difficult to access are to be avoided. Welds, internal radii and transitions must be designed hygienically.
Stainless steel 1.4404 or AISI 316L is frequently used as the material. The product-contact surfaces usually have a defined surface roughness of Ra ≤ 0.8 µm. Depending on the application, they can additionally be ground or electropolished.
The drive and the seals must also be of hygienic design. Bearings arranged above the mixing chamber and encapsulated drive systems reduce the risk of contamination. Lubricants must not come into contact with the product.
The mixing system must homogenise dust-fine, hygroscopic and fatty powders gently. A rotating mixing screw and an orbital movement are frequently combined. This produces intensive circulation with low mechanical loading. At the same time, segregation after the mixing process is to be avoided.
The product is ideally discharged at the lowest point of the cone. Hygienically designed and flush-mounted outlet valves support a high residue-free discharge. Low residues shorten cleaning and increase safety during product changes.
Validatable CIP or WIP systems should be available for cleaning. These include spray heads, rotary cleaners or programmable target-jet cleaning systems. All product-contact surfaces must be fully wetted. The cleaning medium must then be able to drain away reliably. Residual water and the formation of puddles are to be avoided.
Suitable manufacturers also supply extensive evidence. This includes material certificates in accordance with EN 10204 3.1, roughness measurements, weld documentation and qualification documents for DQ, IQ and OQ. Riboflavin tests or comparable cleaning trials can also be used for validation.
In the selection, attention should be paid to references in the fields of infant formula, milk powder or hygiene-critical powder processing. Trials with original products are equally important. In a pilot plant, mixing time, mixing quality, segregation, residual discharge and cleanability can be examined.
Suitable suppliers are usually identified via trade associations, trade fairs and project-specific invitations to tender. A detailed specification should form the basis. It establishes the product data, batch size, mixing quality, cleaning procedure, hygiene class and scope of documentation.
amixon® – precision mixers "Made in Paderborn"
amixon® develops and manufactures high-precision mixing systems, vacuum mixer-dryers, synthesis reactors and granulators at the Paderborn site. The company has an exceptionally high depth of manufacture. Design, engineering, apparatus construction, assembly and quality control take place in its own works.
As a certified welding company, amixon® holds European, Japanese, Korean and American welding qualifications. Every apparatus is designed individually according to the customer's requirements, that is to say according to the respective User Requirement Specification. All essential manufacturing and testing steps are documented throughout.
A comprehensive range for demanding powder processes
The product portfolio comprises vertical single- and twin-shaft mixers of the VM and HM series. Added to these are the cone mixers AM and KoneSlid® KS. The KoneSlid® enables a particularly rapid and almost complete discharge. Depending on the application, residual discharge rates of 99.997 per cent and better can be achieved.
The SpherHelics® hollow-sphere mixer SH was developed specially for particularly sensitive and fragile mixes. Its special geometry enables particularly gentle blending and a very good residual discharge. For very large batches, amixon® offers the Gyraton® mixing silo GM. It can be designed for usable volumes of approximately 10 to 100 m³.
The range also comprises AMK continuous mixers, COM container mixers and EM single-shaft mixers for standard drums. Vacuum mixer-dryers and reactors of the VMT and AMT series make it possible to mix, dry, sterilise and temper in a single apparatus. They can be operated down to an absolute pressure of approximately 5 mbar. The portfolio is completed by ring-layer mixer-granulators of the RMG series.
Many design solutions are amixon®'s own developments. These include SinConvex®, ComDisc®, OmgaSeal®, Clever-Cut®, DosiFlap® and KwickKlamp®.
Gentle mixing at the highest homogeneity
amixon® mixers work with low tool speeds. The circumferential speed can typically be set between approximately 0.8 and 3.5 m/s. The mix is restratified three-dimensionally by the SinConvex® mixing helix. At the periphery it flows upwards. In the centre it flows downwards under gravity.
This forced restratification produces a very high mixing quality even at a low rotational speed. Throwing, impact and crushing loads are largely avoided in the process. The heat input also remains low. Sensitive agglomerates, coatings and particle structures can thereby be preserved. Should agglomerates be broken up deliberately, however, cutting rotors can be switched in. These act locally and do not load the entire batch.
Depending on the design, the mixers can be operated at fill levels of approximately 10 to 100 per cent. Even with widely differing batch sizes, a technically ideal mixing quality remains achievable. A single apparatus can thereby frequently cover a broad range of production quantities.
The apparatus can be executed project-specifically in accordance with EHEDG, FDA, 3-A, USDA, GMP, ATEX and ASME requirements. amixon® also supports its customers with DQ, IQ and OQ. The documentation for amixon® apparatus follows, on request, EU GMP and FDA 21 CFR Part 11.
Verification through trials in the amixon® pilot plant
In the pilot plant in Paderborn, 35 test units are available.