A method of managing the valves of a simulated moving bed separation
system comprising at least one column of adsorbent beds split into
several zones delimited by injection and draw-off points, allowing finer
monitoring of a determined concentration profile. The method comprises,
during each period between the shift times of the injection and draw-off
points, in opening and closing a first valve located at one end of a zone
according to a determined law, while opening and closing the valve
downstream from the first valve in relation to the direction of flow of
the recirculation flow, according to the same law with a lag, referred to
as overlap time, in relation to the first valve, which is less than or
equal to the period, the law imposing a constant total flow rate for the
flow passing through the two consecutive valves throughout the overlap
time. Applications are any simulated moving bed separation system,
preferably those used for relatively small-tonnage production such as
fine petrochemistry, pharmaceutical industry, certain food processing
industries, etc.