Standard Calandria Evaporator


  • The calandria evaporator has vertical tubes usually less than six feet long.

  • The liquid level is maintained above the top tubesheet, and the circulation pattern is up through the tubes and down through a central pipe called a “downcomer”.

  • Circulation is created by the difference in specific gravity between the body liquor and the heated liquor and vapor generated inside the tubes, plus a vapor lift effect.

  • The circulation rate through the downcomer (also known as downtake) is many times the feed rate.

  • The flow area of the downtake is normally approximately equal to the total tubular flow area.