SCALE-UP OF FLUIDIZED-BED PROCESSES - PRINCIPLE AND PRACTICE

Scale-up and commercialization of any chemical process is an inexact s cience and the scale-up of fluidized bed processes is especially so. T he problem of gas bypassing and poor contact with bed particles has be en recognized as a major scaling consideration for a generation. More recently, especially in circulating fluidized beds, the issues of part icle flow patterns and density profiles have become appreciated as imp ortant unknowns in scale-up. Equally important scale-up difficulties o ccur outside the realm of reaction engineering, having to do with the physical nature of solid particles. The importance of all these factor s will be discussed with reference to the commercialization of several fluid bed processes.