INVESTIGADORES
BUCALA Veronica
artículos
Título:
Thermal regimes in cocurrently cooled fixed-bed reactors for parallel reactions: application to practical design problems
Autor/es:
BUCALA, VERONICA; BORIO, DANIEL; PORRAS, JOSE
Revista:
CHEMICAL ENGINEERING SCIENCE
Editorial:
PERGAMON-ELSEVIER SCIENCE LTD
Referencias:
Lugar: Amsterdam; Año: 1997 vol. 52 p. 1577 - 1587
ISSN:
0009-2509
Resumen:
Abstract--The conditions of existence of the seven feasible thermal regimes for exothermic
first-order parallel reactions occurring in cocurrently-cooled fixed-bed reactors are derived
here. The diversity of thermal regimes offered by the cocurrent scheme was applied to solve
practical optimization problems. Theoretical optimal temperature profiles inside the reactor
tubes which maximize the outlet yield of the desired product were determined. These ideal
thermal trajectories were very well tracked by attainable thermal profiles generated by simulation
of a cocurrently-cooled fixed-bed reactor represented by a plug-flow pseudo-homogeneous
model. In fact, the objective function values found at feasible operation conditions were very
close to the optimal ones. These results indicate that the conventional designs such as constant
coolant temperature or the countercurrent scheme (where only hot-spot or decreasing profiles
can be generated) could not handle the optimization problems as efficiently as the cocurrent
configuration. Moreover, the cocurrent design allows, among other advantages, to reach the
specified level of conversion (or yield) with higher selectivity and lower maximum temperature
values than the common constant coolant temperature configuration. These findings imply the
possibility of a significant improvement in the economics of the plant. © 1997 Elsevier Science
Ltd. All rights reserved