Q1. A forward-feed double-effect evaporator,having 10 m2 of heating surface in each effect, isused to concentrate 1 kg/s of caustic sodasolution from 10 per cent by mass to 30%.During a particular run, when the feed is at 373K, the pressures in the two calandrias are 375and 180 kN/m2 respectively, while thecondenser operates at 30 kN/m². For these:conditions, calculate.the load on the condenser (a)the steam economy (b)the overall heat transfer coefficient in each (c).effectWould there have been any advantages in usingbackward feed in this case? Heat losses to the.surroundings are negligible :Physical properties of caustic soda solutionsSpecific BoilingHeat ofheatpoint Concentrationdilution,сарacityrise% wtkJ/kgkJ/kg Kdeg K3.851.6102.33.726.1209.33.6415.0302.23.2241.650

From the given data: λ0=2141kJkgλ1=2211kJkgλ2=2370kJkg0 Making a heat balance around stage…

Q1. A forward-feed double-effect evaporator, having 10 m2 of heating surface in each effect, is used to concentrate 1 kg/s of caustic soda solution from 10 per cent by mass to 30%. During a particular run, when the feed is at 373 K the pressures in the t wo calandrias are 375

Q1. A forward-feed double-effect evaporator, having 10 m2 of heating surface in each effect, is used to concentrate 1 kg/s of caustic soda solution from 10 per cent by mass to 30%. During a particular run, when the feed is at 373 K the pressures in the t wo calandrias are 375

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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