Guidelines for Upgrading Program

It is important to realize at the beginning that it is more difficult and more time consuming to upgrade existing evaporators than to install new evaporators in new piants. Quite often the retrofit construction and plant modifications may resuit in production loss, with the prospect of further losses if the construction schedule slips. 

The first and most important part of any upgrading program for energy conservation is a thorough evaluation of the existing equipment. There are two important reasons for this  

The evaluation should include heat and material balances and should examine major consumers of the thermal energy outside the evaporator area. The most efficient heat-recovery system is usually one that can be used as a heat sink to receive waste heat, and the best location for this may be In another area which can readily receive a high-temperature stream for the evaporator. 

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