Real-time assessment of continuous spray granulation

How to produce washing powder? Just take tiny grains, let them spin around in some air flow and spray liquid on them. During this procedure these tiny particles will grow till they have reached their aimed size. Isnt this procedure well-known for a long time? Of course, engineers producing of washing powder know this procedure since decades. But in todays production processes these grains grow with different rates and the process produces a whole range of grain sizes. Some of them are too small and some of them are too big, and they are thus not suitable for washing powders. These inadequate sized particles have to be grinded and traced back to the production process. This continuous recycling reduces the overall production rate and costs energy. What we want to do? We want to minimize the amount of those traced back particles and reduce unnecessary recycling rates. With our research we aim to make this procedure observable and thus easy to control. By applying real-time simulation, online measurement methods and adaptive process control we aim to produce equally-sized washing powder grains. How to aim these goals? Since we cannot meet these aims by ourselves, we teamed up with a research group in Hamburg. Our German colleagues will build up a dedicated experimental facility for the development of the novel adaptive process control. We in Linz will focus on real-time simulations as well as their alignment with the actual process state of the washing powder grains in the test facilities in Hamburg. Whats beyond washing powders? If we succeed, we can save time and energy, making the production process of washing powder more efficient. However, in a more general frame, you can see this research project as research playground for flow-based digital twins. If we are able to develop a new method for aligning real-time flow- simulation to concurrent process-information, we can achieve some totally new perspective of process observation and control. From our point of view this perspective of a flow-based digital shadow seems to be very fascinating beyond the efficient production of washing powders ...

Tracking thousands of particles in real-time It is actually astonishing how often we encounter products from particulate processes in our daily lives - from the obviously particulate laundry detergent to compressed powder in tablets and simple plastic bottles made from plastic granulate. Due to their wide-spread applications, understanding and optimizing particulate processes is of great importance for the domestic industry. Since such processes are difficult to assess by direct measurements due to e.g. limited optical accessibility, they are often addressed by numerical simulations. Detailed simulations of particulate processes are, in turn, computationally expensive due to the large number of complex interacting particles and can usually only be carried out offline on powerful computers. In this research project, we were able to develop a data-supported simulation method that enables the acceleration of such simulations by orders of magnitude. What used to take a day now only takes a few seconds. Furthermore, these simulations can predict local size changes of the particles and thus can deduce important process-relevant features. Within this project, we were able to demonstrate that thousands of interacting and size-changing particles actually can be calculated in real-time concurrently to the actual process. With this we have created a novel numerical observation tool for particulate processes. We could document our research outcome by scientific contributions in the journals 'Powder Technology' and 'Chemical Engineering Science.'