Process scale-up is about developing new processes for existing products. This scale-up is applied in bulk chemicals and other industry branches with large capacity processes.

Product scale-up is about developing new products to be produced in existing processes. This scale-up is applied in pharmaceuticals, food, consumables, catalyst and fertilizer industry branches.

In process scale-up the main stages taken are concept, feasibility, development, engineering (including procurement and construction) and implementation. Implementation is sometimes sub-divided in demonstration and deployment. Each step contains design and testing. Often modelling also plays a part. Testing units involved are bench-scale, mini-plant, pilot plant, demo plant, deployed commercial plant.
In product scale-up the main stages have different names depending on the industry branch or even the specific company involved. No consensus on stage names is yet available, except for the pharma industry. There the stage names are: Discovery, Pre-clinical, Clinical phase-I, Clinical phase-II, Clinical phase-III, Approval, Commercial. The testing units involved are lab-scale, pilot plant (often a range of pilot plants with increasing capacity), often the pilot plant is called Product Development Unit (PDU), and commercial plant. The scale-up method applied is in most cases empirical. Sometimes modelling is used in combination with the empirical method to reduce the empirical effort and scale-up steps.

In the past these two scale-up methods were applied in the mentioned separate industry branches with little interaction between them. Nowadays however, the product focussed industries often want also to have new process technologies, such as process intensified technologies. Often is also about shifting from batch operation to continuous operation. Then the two totally different scale-up methods have an encounter of the third kind. The encounter may start with confusion that the same words such as scale-up are used for two very different methods. The confusion will be removed by discussion, discussion, and discussion. The descriptions of process scale-up versus product scale-up may help to speed up the discussion, resulting in new clarified scale-up method suitable for the specific company.

I was recently part of such a discussion inside a company involved in product scale-up and process scale-up. This triggered me to write this news item.