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== '''[[Pompeii]]''' ==
== '''[[Fenske equation]]''' ==
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{{Image|Pompeii's forum.jpg|right|200px|"The forum at Pompeii with Mt. Vesuvius in the background."}}
{{Image|Total Reflux.png|right|275px|Industrial distillation column operating at total reflux}}  
'''Pompeii''' was a [[Ancient Rome|Roman]] settlement in [[Campania]], situated where the River Sarno drains into the [[Bay of Naples]]. When Pompeii was founded and who by is uncertain,<ref>Beard, Mary (2008) ''Pompeii: The Life of a Roman Town'', p. 34. London: Profile Books. ISBN 9781846684715.</ref> but by the mid-6th century occupied an area of 66 hectares. In the 1st century it became a Roman colony. In A.D. 79 Pompeii and nearby [[Herculaneum]] were buried when [[Mount Vesuvius]] erupted. The settlement was preserved and has become an important [[archaeology|archaeological]] site. In [[Roman mythology]], Pompeii was founded by [[Heracles|Hercules]] and may have been where the cult dedicated to the demi-god originated.<ref>Cooley, Alison & Cooley, M. G. L (2004). ''Pompeii: a sourcebook'', pp. 6–8, 17. London: Routledge. ISBN 9780415262118.</ref>
The '''Fenske equation''' is used for calculating the minimum number of [[theoretical plate]]s required for the separation of a binary feed stream by a [[Continuous distillation|distillation column]] that is being operated at total [[Reflux (distillation)|reflux]] (i.e., which means that no overhead product is being withdrawn from the column). The derivation of the Fenske equation assumes that the [[relative volatility]] is constant in the distillation column.


The site of Pompeii was lost until the 18th century. Marble which had been worked on by masons was found in the area, and led to investigations which resulted in the discovery of Herculaneum. In 1748, Pompeii itself was discovered. In this first phase of rediscovery, investigations were funded by the wealthy but inflicted much damage on the site as artworks were taken away to be displayed in the patrons' homes. Pompeii and Herculanuem gained international renown in 1762 due to the writings of [[Joachim Winckelmann]], but the first rigorous archaeological excavations only began in 1860.<ref>Renfrew, Colin & Bahn, Paul (2004). Archaeology: Theories, Methods and Practice, 4th edition. Thames & Hudson. pp.  24–25. ISBN 0-500-28441-5.</ref>
Theoretical plates are also often referred to as [[theoretical tray]]s or [[equilibrium stage]]s.


The reason Pompeii is so well known today is not because it was exceptional in its time, but because of its remarkable preservation which offers [[archaeology|archaeologists]] insight into the Roman way of life. In the words of Alison E. Cooley and M. G. L. Cooley: "Pompeii was not a particularly significant Roman town. ... No Pompeian made his mark on Roman literature or politics. No crucial moments in Rome's history hinge on Pompeii. Yet today, because of the accident of its fate, Pompeii is a Unesco world heritage site, attracting up to five hundred times as many visitors each year as actually used to live in the town."<ref>Cooley & Cooley, ''Pompeii: a sourcebook'', p. 1.</ref>
The equation was derived in 1932 by Merrell Fenske, a professor who served as the head of the [[chemical engineering]] department at the Pennsylvania State University from 1959 to 1969.<ref>{{cite journal| author=M.R. Fenske|title=Fractionation of Straight-run Pennsylvania Gasoline|journal=Industrial Engineering Chemistry|volume=24|issue=5| pages=482-485|date=May 24, 1932}}</ref>  


''[[Pompeii|.... (read more)]]''
When designing large-scale, continuous industrial distillation towers, it is very useful to first calculate the minimum number of theoretical plates required to obtain the desired overhead product composition.
 
''[[Fenske equation|.... (read more)]]''


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Revision as of 01:46, 28 October 2012

Fenske equation

PD Image
Industrial distillation column operating at total reflux

The Fenske equation is used for calculating the minimum number of theoretical plates required for the separation of a binary feed stream by a distillation column that is being operated at total reflux (i.e., which means that no overhead product is being withdrawn from the column). The derivation of the Fenske equation assumes that the relative volatility is constant in the distillation column.

Theoretical plates are also often referred to as theoretical trays or equilibrium stages.

The equation was derived in 1932 by Merrell Fenske, a professor who served as the head of the chemical engineering department at the Pennsylvania State University from 1959 to 1969.[1]

When designing large-scale, continuous industrial distillation towers, it is very useful to first calculate the minimum number of theoretical plates required to obtain the desired overhead product composition.

.... (read more)

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