Entry feed water temperature

The reason for using feed heating to set the entry feed water temperature at a level T, above the condenser temperature is that Tb must exceed the dewpoint temperature Tjp of the exhaust gases. If is below Tjp then condensation may occur on the outside of the economiser tubes (the temperature of the metal on the outside of the tubes is virtually the same as the internal water temperature because of the high heat transfer on the water side). With Tb > Tjp possible corrosion will be avoided. 

This is essentially the approach adopted by Ruffi [9] in a comprehensive set of calculations, but he assumed that the economiser entry water temperature 7b is raised above the condenser temperature by feed heating, which was specified for all his calculations. The T,s diagram is shown in Fig. 7.6 the feed pump work terms are neglected so that h.j, = hy and h. = /ib. 

Double click on the Feed stream. Make an entry of the desired feed properties a temperature of 25°C, a pressure of 1 atm, a flow rate of 1000 kg/h, and a feed mass fraction of 0.43 acetone, 0.5 water, and 0.07 MIBK. 

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