Tube bundle reactor

A tube bundle reactor for carrying out endothermic or exothermic gas phase reactions, comprising

• a tube bundle of reactor tubes filled with catalyst, having their ends fastened tightly in tube sheets, a fluid heat carrier flowing around the tubes during operation,
• a shell enclosing the tube bundle,
• a gas inlet head spanning one of the tube sheets,
• a gas outlet head spanning the other tube sheet,
• the reactor tubes being in fluid communication with the gas inlet and outlet heads,
• at least one stage thermometer installed in a thermometer tube disposed in the tube bundle for determining temperature profiles,
• wherein the at least one stage thermometer (9) is axially movable inside the thermometer tube (2), and the tube bundle reactor (1) comprises a mechanical positioning means (8) to effect the axial movement of the stage thermometer (9) in predetermined steps, and the at least one stage thermometer (9) comprises a teletransmission means (29a) adapted to transmit the measured values to a remote control center (30), and that the mechanical positioning means (8) comprises means for the reception of control signals from that control center (30);
• and
• wherein the at least one stage thermometer (9) in the thermometer tube (2) is arranged inside a protective tube (23);
• and
• wherein the at least one stage thermometer (9) inside the protective tube (23) is arranged in a heat protection tube (33) which is axially movable in the protective tube (23);
• and
• wherein the thermometer tube is in fluid communication with the gas inlet head (6) and the gas outlet head (7) and comprises a catalyst therein, the reactive effect of which corresponds to that of the reactor tubes, and that the protective tube (23) extends through at least part of the catalyst, and the heat protection tube (33), including the at least one stage thermometer (9) passes and is movable through, respectively, at least part of the catalyst;
• and
• wherein the spacings (x(TM)) of adjacent individual thermometers (TM) of the at least one stage thermometer (9) are smaller in the area of a hot spot than in the remaining area.