Exergy Economic Analysis Of Three-Effect Falling-Film Evaporation System For Ammonium Chloride Callback

Through the design for three-effect falling-film evaporation system of interleaving flow, the exergy economic analysis of the evaporation system was carried out. The effect of exergy source was fully utilized.Basing on the exergy analysis of the evaporation system the links which losing exergy most was found. The external losing exergy mainly concentrated in the consumption of second-degree vapor. The internal losing exergy mainly caused by the difference in temperature of heat conduction and concentrated heat. The matrix was introduced to optimize the total area of heat conduction. The relation between consumption of vapor and total area of heat conduction was given. If the total area reduced, the amount of vapor would increased. Whereas, if the total area increased, the amount of vapor would reduced. The multi-effect evaporation system can't be designed in order that both total area of heat conduction and consumption of vapor were least. While the method of Lagrange was used to optimize the system, the optimized flow was gained. The flow was appended jet pump behind the first effect and the second effect. By this means, the second-degree vapor was improved and internal losing exergy caused by the difference in temperature of heat conduction and concentrated heat was reduced. It proved by economic calculation that this flow could acquire marked economic benefit.A new design program for three-effect evaporation system of interleaving flow was educed. It provided a preferable base for the design of multi-effect evaporation system.