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imported>Chunbum Park
(→‎Pompeii: Fenske equation)
imported>Chunbum Park
(Steam generator)
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== '''[[Fenske equation]]''' ==
== '''[[Steam generator]]''' ==
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{{Image|Total Reflux.png|right|275px|Industrial distillation column operating at total reflux}}
A '''steam generator''' is a device that uses a [[heat]] source to [[boiling point|boil]] liquid [[water]] and convert it into its [[Gas|vapor]]  phase, referred to as [[steam]]. The heat may be derived from the [[combustion]] of a [[fuel]] such as [[coal]], [[Petroleum crude oil|petroleum]] [[fuel oil]], [[natural gas]], [[municipal waste]] or [[biomass]], a [[nuclear fission]] reactor and other sources.
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that is being operated at total [[Reflux (distillation)|reflux]] (i.e., which means that no overhead product is being withdrawn from the column).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.


Theoretical plates are also often referred to as [[theoretical tray]]s or [[equilibrium stage]]s.
There are a great many different types of steam generators ranging in size from small medical and domestic [[humidifier]]s to large steam generators used in [[conventional coal-fired power plant]]s that generate about 3,500 [[kilogram]]s of steam per [[Watt|megawatt]]-hour of [[energy]] production. The adjacent photo depicts an 1150 M[[Watt|W]] power plant with three steam generators which generate a total of about 4,025,000 [[Kilogram|kg]]/hour of steam.


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>
Many small commercial and industrial steam generators are referred to as ''"boilers"''. In common usage, domestic water heaters are also referred to as ''"boilers"''. However, domestic water heaters do not boil water nor do they generate any steam.


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.
''[[Steam generator|.... (read more)]]''
 
''[[Fenske equation|.... (read more)]]''


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Revision as of 07:52, 6 November 2012

Steam generator


A steam generator is a device that uses a heat source to boil liquid water and convert it into its vapor phase, referred to as steam. The heat may be derived from the combustion of a fuel such as coal, petroleum fuel oil, natural gas, municipal waste or biomass, a nuclear fission reactor and other sources.

There are a great many different types of steam generators ranging in size from small medical and domestic humidifiers to large steam generators used in conventional coal-fired power plants that generate about 3,500 kilograms of steam per megawatt-hour of energy production. The adjacent photo depicts an 1150 MW power plant with three steam generators which generate a total of about 4,025,000 kg/hour of steam.

Many small commercial and industrial steam generators are referred to as "boilers". In common usage, domestic water heaters are also referred to as "boilers". However, domestic water heaters do not boil water nor do they generate any steam.

.... (read more)