The development of increasingly active substances as well as the tightening-up of corporate and statutory regulations with regard to personal safety result in ever higher requirements to protect personnel from contact with these powdery active substances. To meet these requirements, a great variety of different systems has been developed over the last years which create a barrier between the operator and a possible dust exposure. We are talking here about so-called isolators, which constitute an enclosed housing around the process units where a dust exposure is considered likely. Processes realised with isolators include:
- Sampling
- Particle size analysis
- Filling
- Metering
- Grinding/micronisation
- System component cleaning
The integration of processing systems into isolators poses high engineering demands. When customising an isolator, the following points must be paid particular attention to:
- Transfer port system concept
- Operator-friendliness (ergonomics)
- Product yield
- Cleanability
The isolator must be integrated into an existing product flow, meaning that special attention must be paid to the process steps upstream and downstream of the isolator. The method and shape of the feed or filling containers have a decisive influence on the transfer port concept. Dependent on the batch size or OEL, double-flap transfer ports (RTPs) or continuous liner systems are available.
One of the greatest challenges when integrating processes into isolators is to ensure that the entire system can be operated comfortably, i.e. ergonomically. This simple statement puts extreme demands on the manufacturers of complex systems in terms of design of both the process components and of the isolators.
After 3D-CAD modelling, a wooden mock-up is usually made which depicts the most important process sections and which serves to determine the final design.
One advantage of integrating processes into a containment system is that the contaminated cubic volume is significantly reduced. After all, it is not the complete clean room with the associated interior that is contaminated but rather "only" the inside of a steel box. And to counter this, isolators are equipped with cleaning systems. These systems generally comprise ductings that taper into spray nozzles on the inside of the isolator. In addition, a spray pistol is used in most cases.
The know-how gathered by the Hosokawa Group in this field over the years has put Hosokawa Alpine in the position of being able to supply complete systems which considerably reduce the customer's planning and coordination complexity and which ensure reliable system operation. The realisation of numerous containment projects as well as the close cooperation with the customer highlight the competence and experience of Hosokawa Alpine on this sector.