Thermal Design of Evaporators

F. C. Standiford/ M.S./ P.E./ Member American In stitute of Chemical Engineers, American Chemical Society. (Thermal Design of Evaporators, Evapor ators)... 

Standiford, E.C. Thermal design of evaporators. In Perry s Chemical Engineers Handbook Perry, R.H., Green, D.W., Maloney, J.O., Eds. McGraw-Hill Book Company New York, 1984 10-34-10-38. 

The prior and substantial contributions of Frank L. Rubin (Section Editor, Sixth Edition) and Dr. Kenneth J. Bell (Thermal Design of Heat Exchangers, Condensers, Reboilers), Dr. Thomas M. Elynn (Cryogenic Processes), and E. C. Standiford (Thermal Design of Evaporators, Evaporators), who were authors for the Seventh Edition, are gratefully acknowledged. 

Important aspects in thermal design of evaporators used in relation to concentration and crystallization in the process/chemical industry can be summarized as follows [119] ... 

Also like distillation, the thermal profile of evaporators can be manipulated by changing the pressure. However, the degrees of freedom in evaporator design open up more options. 

The heat input to diyers is to a gas and as such takes place over a range of temperatures. Moreover, the gas is heated to a temperature higher than the boiling point of the liquid to be evaporated. The exhaust gases from the dryer will be at a lower temperature than the inlet, but again, the heat available in the exhaust will be available over a range of temperatures. The thermal characteristics of dryers tend to be design-specific and quite difierent in nature from both distillation and evaporation. 

Thermal and mechanical design of heat exchangers (condensers and evaporators) is presented earlier in this section. 

In classic electro-thermal atomizer the process of formation of the analytical signal is combination of two processes the analyte supply (in the process of evaporation) and the analyte removal (by diffusion of the analyte from the atomizer). In double stage atomizer a very significant role plays the process of conductive transfer of the analyte form the evaporator to the atomizer itself and this makes the main and a principle difference of these devices. Additionally to the named difference arises the problem with optimization of the double stage atomizer as the amount of design pai ameters and possible combination of operation pai ameters significantly increases. 

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