Energy retrofit study of an ammonia plant

Detailed energy integration study of the front-end of an existing ammonia p lant has been performed, using recent advances in Pinch technology. Utility loads demanded by the existing process were found to be very close to the calculated minimum targets. This indicated that the selected ammonia plant is well integrated, and not much saving is expected through process-to-proc ess energy integration. Alternatively, the retrofit study concentrated on b etter placement of available utilities. Two promising options have been inv estigated. The first one studied the flue gas temperature in the convection section of the primary reformer, and proposed new arrangements of the heat ing coils. Boiler feed water heating for high-pressure steam generation has been also considered as a possible source for reduction in energy consumpt ion. Total benefit claimed amounted to 17.6% reduction in combustion fuel c onsumption. The overall results of this case study are promising, However, economical evaluation of the proposed modifications is essential. Additiona l possible reduction in energy consumption is also possible in energy and p ower integration of the back-end section. (C) 2000 Elsevier Science Ltd, Al l rights reserved.