Today's Tools in the Scale up and Optimization of Today's Fluidized Processes

Commercial fluidized beds have been around for a century with the development of the fluidized bed gasifier by Fritz Winkler. Historically, designing and scaling up these units was Edisonian because tools, concepts, and understanding were limited. Commercialization usually required several pilot scale units differing by conservative increases in size, yet the hydrodynamics were often poorly understood.

Today that is no longer the case. Cold flow modeling, probe development, and computational fluid dynamics (CFD) have reduced the number of pilot units needed, increased the scaling factors between iterations, and decreased the time to commercialization.

Today, the most effective methodology is to complement experiments with modeling in all stages of the scientific method. At the start, simple experiments provide vital inputs for the models. Well-defined models, in turn, are used to explore hypotheses and are valuable tools in building and managing the design space for additional and more sophisticated experiments. During and after the data collection, the models are further used to assist in the data analysis. What the models do not capture is equally important as what the models do capture, providing insights into the importance of phenomena beyond those used during model formulation. Key scale parameters are determined from both experimental and modeling results, along with invaluable engineer experience. Finally, the models once again become a vital tool in designing pilot, process demonstration, and full commercial-scale plants. The combination of these tools, used in the correct sequence, saves years of development efforts.

Multiple examples are presented, including fluidized catalytic cracking (FCC), gasification, and pyrolysis of waste plastic. Recent trends are explored whereby numerous sustainability applications are increasingly turning to fluidized processes.

The impact of today’s tools on the urgency of commercialization for today’s sustainability, renewables, and decarbonization applications is discussed, accelerating solutions for some of our most critical challenges.