The container glides into place virtually soundlessly, smoothly approaching its destination, the CleanDock. Elegance in stainless steel. Cleanly, confidently and reliably. Then it comes to a stop. The pneumatic gripping system of the active section advances from above, grips the container fastener of the passive section and lifts it. Two to three short air blasts indicate that the dosing element and target container are seamlessly joined. The flexible compensator of the passive section makes it possible to precisely tare the scale positioned under the container, independently of the product quantity it already holds. Then the filling of the bulk material begins. Once this process has ended, the active and passive sections detach from each other just as elegantly and cleanly and the container moves to the next filling station. What no one sees from the outside: almost the entire filling process is controlled decentrally by the CleanDock itself.
“Our systems transport and dose all conceivable types of bulk materials,” says Frank Pahl, Head of Development at AZO GmbH + Co. KG in Osterburken. “They range from milk powder and ingredients for baby food to pharmaceuticals and detergents as well as different plastics and pigments, for example for wet paint production. We could report on the variety of implemented applications from our four areas of business Food, Vital, Chem and Poly for days." With more than 1000 employees worldwide, AZO has been making its technological mark in the area of bulk material handling for 70 years. One of the current pioneering innovations is the latest generation of CleanDock. With this system, AZO is taking an important step toward fast commissioning, error reduction and increased safety in the filling of bulk materials together with its long-term partner and automation expert Festo. To do this, CleanDock has been provided with intelligence in the form of a decentralized controller, and thus autonomy in the process. While the process control system takes care of the big picture in terms of control technology, the modular electrical terminal CPX with integrated controller CEC and valve manifold MPA from Festo assumes the detailed processes of the docking and undocking procedures.
"Bulk material handling is an art in itself that requires a lot of experience," says Frank Pahl. "A handful of flour contains more particles than gravel on an entire lorry. In the handling of plastics, infamous angel hair can arise; higher grinding degrees and finer powders with smaller particles in cosmetics and pharmaceuticals present us with new challenges daily. Bulk materials and bulk material technology are in motion. Our systems must handle these tasks without a problem – and they do. We are proud of that." Two of the greatest challenges of the bulk materials industry remain the prevention of cross-contamination and the unwanted release of dust. On the one hand, the objective is product purity and, on the other, employee protection. In the past few years, the pharmaceutical and food industries, in particular, have increasingly focused on this but the chemical industry has too. During the handling of bulk materials, dust from allergenic foods, for example, can lead to health impairments in operating personnel. In addition, explosion prevention and protection play a large role. The high number of different containers for the transport and handling of raw materials, as well as intermediate and finished products, make things no easier for the designers of bulk material systems. These include FIBCs, drums, sacks and portable containers. As in other areas of industry, the factor of flexibility is gaining importance in bulk material handling.