Lits fluidisés pour l'industrie chimique. Extrapolation et amélioration des catalyseurs. Deuxième partie : Stratégie n'utilisant que des expériences de laboratoire. Troisième partie : Etudes théoriques, réalités expérimentales, suggestions

摘要

The first catalytic fluidized beds appear near 1942 in petroleum industry and near 1960 in chemical industry. We only consider here very high-performance chemical fluidized bed reactors (> 99%). In the past, they were developed through the use of very expensive pilot plants of about 0. 5-m-diameter and 10-m-high. We will demonstrate that direct scale-up from laboratory data is possible. This possibility gives also a simple method to improve catalysts used in operating units and opens fluidized bed technique to products that need only low-range production. Presentation is made within three parts:- In the first, Studies, Models, Learning from Pilot Plants* : after a description of the major scale-up problems, studies to solve them were summarized. Then scale-up works of two processes with the use of about 0. 5-m-diameter pilot plant were given. From the results, it was deduced the possible performances of a catalytic fluidized bed and how to operate to obtain them. - In the second, Scale-up with Only Laboratory Data,it is experimentally demonstrated that the information's scale-up can be obtained in a laboratory. A strategy to obtain them is suggested. Another result of these experimental studies is that all physical properties of catalytic fluidized bed depends on only one parameter called comportment incipient fluidization velocity.- In the third, Theoretical Studies, Experimental Reality, Suggestions,results of theoretical studies about bubbles of the fluidized beds are summarized. Results are often given through one-parameter mechanistic models. This parameter is the bubble diameter. To confront these mechanistic models to experiments, a relation is established between the bubble diameter and the comportment incipient velocity fluidization. Suggestions to improve bubble models are suggested and general conclusions about fluidized beds are given.