Ploughshare® Mixers are proven systems that are used in the pharmaceutical industry. For many decades these machines have been successfully employed for mixing, granulating and drying high-quality pharmaceutical products.
The highest standards of quality and safety are prerequisites in pharmaceutical production. They are ensured, among other things, by the globally valid GMP (Good Manufacturing Practice) guidelines. It is consequently only logical that technical innovations in this particularly demanding environment are slow in arriving. Provided they satisfy GMP requirements, processing machines and systems can generally be employed in the pharmaceutical industry. This also applies to Ploughshare Mixers.
Advantages
The advantages of a horizontal Ploughshare Mixer lie in the short mixing time – usually between two and three minutes – with the highest mixing precision in the 1:100,000 range, and higher for many products. This is enabled by a fluid bed created by the mixing elements, and thus mechanically generated. By using a constant Froude number, which is an indicator of product movement in the machine, test results or validated processes can be reliably transferred from one mixer size to another. By virtue of its horizontal design, the Ploughshare Mixer requires significantly less drive power and reduced construction height compared to conventional, vertical high-shear mixers.
Besides usage as a mixing system, the Ploughshare Mixer can also be employed for granulation processes. A granulation agent can be introduced to the fluid bed by a number of different methods. The interaction of product particles, mixing elements and mixing drum, together with the resulting shear forces, causes granules to form. The results achieved are absolutely comparable with those of vertical high-shear Mixers. The desired granule size can be set with the aid of one or more rapidly rotating choppers which break up any lumps. Optional discharge through an integral sieve mill for final size calibration of the moist granules completes the process engineering possibilities of this system.
Classic applications for a Ploughshare Mixer in the pharmaceutical industry are:
- Manufacture of premixes: Based on downstream production stages, e.g. continuous granulation, roller compacting or extrusion, highly precise premixing of all active ingredients and additives (also in liquid form) is often required. Ploughshare Mixers are used here due to the high mixing quality and wide range of batch sizes.
- Addition of lubricants: In the classical tablet manufacturing process the granules are mixed with a lubricant (usually magnesium stearate) prior to compressing in the tablet press. A Ploughshare system can be used here as an alternative to the commonly used container blender. Several upstream process stages (e.g. premixing and granulating) can take place in the same machine.
- Wet granulation: The Ploughshare Mixer is employed in classical tablet manufacturing for the wet granulation of tablet masses as a space-saving and cost-effective alternative to vertical high-shear mixers. Direct discharge through a sieve mill into a fluid bed dryer is possible.