Vessel for regeneration of a catalyst including monitoring and monitoring and control of combustion completion

A vessel regenerating used catalyst comprising at least two combustion zones including a first combustion zone provided with at least two walls (5a, 5b) between which the catalyst circulates as a moving bed, and provided with at least one conduit (4) for introducing at least one oxygen-containing gas entering the moving bed via one of the walls and leaving via another wall, and a conduit removing oxygen depleted gas from the vessel, and including a second combustion zone, provided with a second conduit introducing at least one oxygen-containing gas, said vessel further having a lower section accommodating, a flame front (36) and said vessel further comprising a zone (FC) monitoring and controlling the end of combustion located below the section accommodating the flame front of a last of the combustion zones (Z2), said monitoring and control zone (FC) being provided with a third conduit (11) introducing an oxygen-containing monitoring and control gas and at least one device measuring the temperature and/or the oxygen content in the gas and/or the catalyst leaving the monitoring and control zone, said third conduit (11) being separate and below said at least one conduit (4), and at least one separator (29) located between the monitoring and control zone and the last of the combustion zones so as to prevent the passage of gas and allow passage of the catalyst.