Scale-up of binder agglomeration processes

This review article describes scale-up of batch and continuous granulation processes where liquid binder is added to fine powder in order to form a granular product. The technical goal of scale-up is to maintain similarity of critical product attributes as the production scale and/or throughput of a manufacturing process is increased. This paper provides a framework for scaling-up that considers critical process transformations in relation to the desired product attributes. A similar approach can be taken in developing process control strategies. In any agglomeration process, transformations can be used to describe how raw materials (typically fine powders and liquid binders) are converted into a granular product. Often the critical product attributes are characterized on the scale of individual granules (e.g., size, shape, porosity, mechanical strength, etc.). On the other hand, industrial scale-up requires predictive relations for the sizing, design and operation of process equipment. Considering scale-up on the basis of transformations is one way to link the macro-scale equipment decisions with micro-scale product attributes. This approach can be applied to the scale-up of batch and/or continuous granulation processes as well as transitioning from small batch prototypes to continuous production circuits.