Abstract: This paper introduces the operation of a 3.2Mt/a continuous reforming unit with mixed feed heat exchanger replaced by spiral wounded heat exchanger in an aromatic hydrocarbon project of a company. Combined with the structural characteristics of plate heat exchanger and spiral wounded heat exchanger, the paper compares and analyzes the operating parameters before and after the replacement. And it is found that spiral wounded heat exchanger is superior in performance in such aspects as lower temperature difference at the hot end, reduced tube and shell pressure and uniform distribution of fluid at tube and shell side. This eliminates the impulse fluctuation of the shell outlet pressure and realizes a great reduction of the hydrogen-oil ratio of the reforming reaction and pressure drop of the reforming hydrogen system. And the energy saving and consumption reduction effect is remarkable.

Key words: continuous catalytic reforming unit/CCR unit, plate-shell heat exchanger, spiral wounded heat exchanger, replacement