Chapter 18. -DISTILLING PLANTS 



condensed in the condensing section and is dis- 

 charged to the test tanks as distillate. 



The first- effect distillate which was used in 

 the second- effect tubes to boil and vaporize the 

 feed in the second- effect shell is discharged 

 through the second- effect tube nest drain reg- 

 ulator and is led to the distilling condenser by 

 way of a flash chamber. The flash chamber is es- 

 sentially a receptacle within which the vapor, lib- 

 erated when the second- effect drains are reduced 

 to a pressure and temperature corresponding to 

 the distilling condenser vacuum, is separated 

 from the condensate and directed to the distilling 

 condenser. As may be seen in figure 18-6, the 

 flash chamber is located just outside of the sec- 

 ond- effect shell. 



The distilling condenser circulating water 

 pump takes suction from the sea and discharges 

 the sea water through the shell of the distillate 

 cooler (which is external to the unit) and then 

 through the tubes of the distilling condenser. 

 Some of the cooling water is then discharged 

 overboard; but a portion (which is now called 

 evaporator feed) goes through the feed heating 



section of the distilling condenser, through the 

 air ejector condenser, and through the 

 first- effect vapor feed heater before it is dis- 

 charged to the first- effect shell. These paths of 

 the distilling condenser circulating water and the 

 evaporator feed may be traced in figure 18-5. 

 As previously described, some of the sea 

 water feed in the first- effect shell is boiled and 

 vaporized by the supply steam. The remaining 

 portion becomes more dense and has a higher 

 salinity than the original sea water feed; this 

 denser, saltier water is called brine to distin- 

 guish it from sea water. After a certain amount 

 of sea water feed has been vaporized in the first- 

 effect shell, the remaining brine is led to the 

 second- effect shell through a pipe that has a man- 

 ually controlled feed regulating valve installed 

 in it. When the feed regulating valve is open, the 

 higher pressure in the first- effect shell causes 

 the brine to flow from the first- effect shell to the 

 second- effect shell. After the brine has been used 

 as feed to generate vapor in the second- effect 

 shell, the remaining brine is discharged over- 

 board by the brine overboard discharge pump. 



FIRST-EFFECT 

 SEPARATOR 



SECOND-EFFECT 

 SEPARATOR 



VAPOR FEED 

 HEATER 



FIRST-EFFECT 

 TUBES 



FIRST-EFFECT 

 DRAIN REGULATOR 



DISTILLING 

 CONDENSER 



DIVISION PLATE 



AIR BAFFLE 



SECOND-EFFECT 

 TUBES 



FLASH 

 CHAMBER 



BRINE PUMP 

 SUCTION 



SECOND-EFFECT 

 DRAIN REGULATOR 



Figure 18-6.— Cutaway view of Soloshell double-effect distilling plant. 



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