Bulk solids usually require several process steps before the final product is obtained. Drying is one of the most important basic process engineering operations.
Moist products with a water content of up to 85 % can be dried particularly gently thermally and mechanically by convective drying in the fluidised bed, where high specific surfaces and an optimum mixing of product and carrier is reached. Nowadays, many powders are dried from suspensions or solutions with the aim of obtaining a very fine powder to improve bioavailability or solubility. And processes that yield dust-free, free-flowing products with good wettability (instant products) or directly compressible carriers.
Different processes
In the WFP-Koni different processes can be realised: drying, spray drying, spray granulation, agglomeration and coating. By varying the parameters of spray pressure, liquid quantity, powder recirculation, hot air quantities and hot air temperature, powders from less than 10 micrometres to pellets can be produced.
Continuous systems
Due to the economic pressure, production processes have to run more and more efficiently. Continuous systems have advantages here, as set-up times such as charging and discharging are eliminated and temperature profiles can be set stationary via different equipment segments. Energy- and time-intensive heating and cooling procedures are no longer necessary.
Since different process steps have to built in one unit, the technical implementation in the machine is very demanding. To determine the individual parameters for customer-specific products, DMR has developed a continuously operating fluidised bed pilot plant.
Fluidised bed pilot plant
- The equipment essentially consists of the processor, the air preparation unit and the control system.
- Process filters are mounted in the upper part of the processor to retain dust particles and return them to the fluidised bed. This is where the separation between the product raw gas side and the clean gas side takes place.
- The spray technology consists of heatable multi-substance spray nozzles that can be used for top and bottom spray processes.
- The air technology is designed in such a way that the system can be operated in fresh air, exhaust air or recirculation mode. Air treatment/conditioning depending on the necessary process requirements.
- Other inert gases such as N2 or CO2 can be used instead of air, with permanent monitoring of the oxygen content.
- The systems enable fast and efficient cleaning and product handling.
- Production manufacturing according to GMP and FDA guidelines
