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Performances of falling film evaporators

Published online by Cambridge University Press:  01 June 2009

R. Selwyn Jebson  and
Mani Iyer
R. Selwyn Jebson
Affiliation:
Food Technology Department, Massey University, Palmerston North, New Zealand
Mani Iyer
Affiliation:
Food Technology Department, Massey University, Palmerston North, New Zealand
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Summary

The performances of falling film evaporators used in the New Zealand dairy industry for concentrating skim milk, whole milk and buttermilk were evaluated by determining (1) the kg steam used per kg water evaporated, and (2) the heat transfer coefficient of each pass in the evaporators. A computer program was used to calculate the results. The heat transfer coefficients varied from 0·3 to 3·2 kW/m2 per °C and the steam consumption from 0·4 to 0·09 kg steam/kg evaporation. The viscosity of the feed and the momentum of the vapours passing down the tubes were found to be the main factors controlling the heat transfer coefficient. A correlation between the heat transfer coefficient and these factors is presented. Other factors likely to have an influence on the performance are discussed.

Type
Original articles
Information
Journal of Dairy Research , Volume 58 , Issue 1 , February 1991 , pp. 29 - 38
Copyright
Copyright © Proprietors of Journal of Dairy Research 1991

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References

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