1. General presentation

This contacting technique offers a number of advantages which led to its development in the years following the Second World War. The most advantageous properties of fluidization are as follows:

• the solid phase is perfectly mixed within the suspension. As a result, the fluidized bed is completely homogeneous in temperature. This homogeneity gives fluidized beds an undeniable advantage over fixed beds, which are often subject to a steep temperature gradient;

• The heat transfer coefficient between the suspension and the heat exchanger tubes is very high [usually between 200 and 600 W/(m ² · K)] and allows the material to be heated or cooled efficiently;

• the fluidized bed can be operated in batch or continuous mode (semi-batch or open)....