This paper present a new kind of equipment called the annular reactor,
which has been designed to treat a great number of substrates with a
particularly good uniformity of thickness of deposits on the batch. Fu
rthermore, a small scale pilot plant of this apparatus, called the sec
tor reactor, has been built. It constitutes a very convenient laborato
ry piece of equipment, particularly useful to perform, at low cost, th
e unavoidable experimental part of the development of any new applicat
ion. Theoretical and experimental results obtained with these reactors
are presented and compared to those obtained when using tubular react
ors. First tests in order to produce cheap thick layers are also repor
ted.