PP311 Distillation

8/8/2019 PP311 Distillation

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Distillation

Distillation is a kind of seperation technique of two or more volatile liquid compunds byusing the difference in boiling points and

relative volatility. The process takes place in a column, and two

heat exchangers. In the column two phases, liquid and gas, are

distributed to enrich the vapor in morevolatile compounds and enrich the liquidphase on less volatile compounds.

Mass transfer is the key to a successfuldistillation.


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imple or batch or differential dist i l lation


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he Rayleigh Equation

:for the still see the Figure below les of liquid originally in still

s of liquid remained in still( )uid composition in still mole fraction of A

( )id composition in still mole fraction A,he amount of liquid in the still is L with mole fraction of A in the liquid bei

( + ) , ,fferential time t dt a small amount of vapour dL is produced and the( ).in the vapour is y mole fraction The vapour I

n equi librium .with the residue liquid The amount of liquid in the still is

( - ), ( - ).m L to L dL while the liquid composition changed from x to x dx

:Performing a material balance on A= +Initial amount in still Amount left in still Amount vaporized

, We have= ( - ) ( - ) +L x dx L dL y dL= - - + +L xL x dL L dx dx dL y dL

, :Neglecting the term dx dL the equation reduces to= -dx y dL x dL

- :Re arranging gives the following Integrating from L 1 to L 2, and from x 1 to x 2, we obtainthe :a yle ig h E qu at io n
http://www.separationprocesses.com/Distillation/Fig013c.htmhttp://www.separationprocesses.com/Distillation/Fig013c.htmhttp://upload.wikimedia.org/wikipedia/en/3/35/Steam_Distillation.JPG


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t ea m di st il la ti on

( )he boiling point of pure water 100 C and for( ).henylamine 184 Ct 98 C , he saturated vapour pressures of the two pure:iquids are

: .enylamine 7 07 kPa: .ater 94 3kPa .ormal atmospheric pressure is 101 325 k
http://upload.wikimedia.org/wikipedia/en/3/35/Steam_Distillation.JPGhttp://upload.wikimedia.org/wikipedia/en/3/35/Steam_Distillation.JPGhttp://upload.wikimedia.org/wikipedia/en/3/35/Steam_Distillation.JPG


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t ea m d is ti ll at io n

acuum dis ti ll at ion

team dist illation with vacuum


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If you boil a liquid mixture C 1, you will get a vapour with composition C 2, which you( ).can condense to give a liquid of that same composition the pale blue lines

If you reboil that liquid C 2, it will give a vapour with composition C 3. Again you( ).can condense that to give a liquid of the same new composition the red lines

Reboiling the liquid C 3 will give a vapour still richer in the more volatile( ).component B the green lines You can see that if you were to do this once or twice

, .more you would be able to collect a liquid which was virtually pure B The secret of getting the more volatile component from a mixture of liquids is

- - .obviously to do a succession of boiling condensing reboiling operations

-int composition diagram for a mixture of two liquids at atmospheri)gram for a mixture of two liquids


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Fractional Distillation

Packed tower
http://www.energybulletin.net/image/uploads/40234/Fractional_distillation.gifhttp://www.energybulletin.net/image/uploads/40234/Fractional_distillation.gifhttp://www.energybulletin.net/image/uploads/40234/Fractional_distillation.gif


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Packed tower

( )Stacked rashig ring top view


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Equipment Designs

Plate Columns (TrayColumns) Packed Beds


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Plate Columns (Tray

Columns) It is the most widely used kind of

distillation column.

Trays are shaped to maximize theliquid-vapor contact andincrease the mass transfer area.

Tray types include sieve, bubblecap and valve.


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li id


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vapor

liquid


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Advantages &

DisadvantagesAdvantages Least expensive colum

for diameters greaterthan 0.6m

The liquid-vapor contactin the plate columns ismore effective than inpacked columns.

Cooling coils can be

easily added to theplate column Can handle high liquid

flow rates.

Disadvantages Higher pressure drops

than packed columns

Foaming can occurbecause the liquid isagitated by the vaporflowing up through it.


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Packed Beds Packings can be provided into 3 types:

1. random/dumped , 2. regular/stacked and 3.structured/ordered.

Random/Dumped packing constitutes of bulk inert materials.Random packings are simply dumped into the tower duringinstallation and allowed to fall at random.

Stacked packing: stacked by hand

Structured packing: ordered geometry. Generally made of

perforated corrugated metal, with adjacent sheets arranged sothat liquid liquids spread over their surfaces while vaporflowsthrough channels formed by corrugations.

Important criteria for packing required are : large interfacial


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S ta cke d ra sh ig rin g( )top view


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Advantages &

Disadvantages When the

diameter is lessthan 0.6m it is

less expensivethan the platecolumn.

Packing is able tohandlecorrosivematerials.

Lower pressuredrop than inplate columns.

Good for

Can break duringinstallation or dueto thermalexpansion.

Not cost efficient forhigh liquid flowrates.

Contact efficiencies

are decreasedwhen the liquidflow rate is toolow.
http://www.energybulletin.net/image/uploads/40234/Fractional_distillation.gif


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Fractional DistillationPacked tower
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Packed tower

( )Stacked rashig ring top view

S ?12 Y21 tage


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Stage ?12 Y21 tage

device where-- 2 phases are brought into intimate contact

.mass transfer takes place between 2 phases leading to bring them to eqm the phases are separated after mass transfer takes place

.Sufficient time eqm

. = =Eqm Stage theoretical stage ideal stage

:fficiency .fractional approach to eqm which a real stage produces1

*2

12

y y y y

=


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Bof pressurevapor Aof pressurevapor

/PPyvolatilitrelative BA ==== B

B

A A

x y

x y

AB

:For binary mixtures x

= 1 - x A; y

=

1 - y A

relationmequilibriu/

)1(1

==+

= B A P P x

x y

apor liquid equil ibrium

Numerical measure of the ease with which the components may be separated AB = ,1 separation is not possible

is t i l lat ion is a kind of separation technique of two or more volatile liquid compounds by using the difference in boiling

.points and relative volatility


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L X V Y


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L -1 , X -1

Ln, Xn V +1 , Y +1

Vn , Yn

tage n2

1

1

2

D L

Dx

x D L

L

y n D

nn

n

n +++=+1

111

++

+=+

D

Dn

D

Dn

R

x x

R

R y

off ken product tatopof flow

refluxasreturnedflow

== D L

R D

CONSTANT MOLAL OVERFLOW

D B F Dx Bx Fx

D B F

+=+=

B L Bx

x B L

L y

m

Bm

m

mm

=+1 B L

Bx x

B L L

y Bmm =+1


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Operating Lines

From steady statematerial balances:

Rectifying section:

Stripping section:

Written in terms of theReflux Ratio:

Rectifying section:

Stripping section: D L

Dx x D L

L y

n

Dnn

nn +++=+1

B L

Bx x

B L

L y

m

B

mm

m

m

=

+1

D L

R D =

111 +++=+ D Dn

D

Dn R x

x R R

y

B L

Bx x

B L

L y B

mm

=

+1


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2

1

1

2

1

L -1 , X -1

Ln , Xn V +1 , Y +1

Vn , Yn

tage n

1


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=ion of feed moles of l iquid flow in the strippi


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F qV V )1( +=

qF L L +=

Dnnn Dx x LVy +=+1 3 F qV V )1(

= 2

Bmm Bx x L yV =+1 4

qF L L = 1 3 4

+

= q

x x

q

q y F

11

x x x

y y y

nm

nm

==

==++ 11:t intersect ion

-l ine equat ion or

quation for feed line

=ion of feed moles of l iquid flow in the strippilts rom introduction of each moles of feed

L V

Feed plate

V L


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)(

1 F b pLT T c

q +=

)( d F pV T T cq=

-he value of q for cold liquid feed is found from the equation

:he value of q when the feed is superheated vapor


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q = 0 (saturated vapour)q = 1 (saturated liquid)0 < q < 1 (mix of liquid and vapour)q > 1 (subcooled liquid)q < 0 (superheated vapour)

+

= q

x x

q

q y F

11

ons ruc on nes or c a e


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Lecture 13: McCabe-Theile 37

ons ruc on nes or c a e-Thiele Method

Equilibriumcurve

45 line

X=x FxB

y

yB

yN

Stripping Section:Operating line

xD

Rectifying Section:Operating line

q-line

q=1 q>1

0


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Bof pressurevapor Aof pressurevapor

/PPyvolatilitrelative BA ==== B

B

A A

x y

x y

AB

:For binary mixtures x = 1 - x A; y =1 - y A

relationmequilibriu/)1(1

==+

= B A P P x x

y

apor liquid equil ibrium

Numerical measure of the ease with which the components may be separated AB = ,1 separation is not possible

is t i l lat ion is a kind of separation technique of two or more volatile liquid compounds by using the difference in boiling

.points and relative volatility

n mum e ux or


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39

n mum e ux orMcCabe-Thiele

Equilibriumcurve

xFxB

y

yN

xD

By returning no exiting vapor as refluxand no exiting liquid as boilup theoperating line intersection is as far tothe left as equilibrium allows.

Although this is the minimum amountof reflux, it takes infinite stages (notethe pinch point between the operatinglines and equilibrium).

1min

min

+=

R

R

x x

y x

q D

q D

),( D D x x),( qq y x

:n actual practice

.2 R

m > 1),phase splitting may occur and a minimum-

boiling heterogeneous azeotrope forms,having a vaporphase inequilibrium with

two liquid phases.

n-butanol/water T-xy


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New Mexico State University

diagram see animation on course

website


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created in Aspen Plus

analyze stripping column 1


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21 BBF +=2bot,B21bot,B1B xBxBFz +=

( )( )2bot,B1bot,B

2bot,BB1 xx

xzFB

= ( )( )1bot,B2bot,B1bot,BB

2 xxxzFB

=

rearrange as

1bot,B1

B1

B x1VL

xVL

y

=


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x ,bot1

x

1bot,B1

B1

B x1VLx

VLy

=

analyze column 2


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2bot,B2

B2

B x1VLxVLy =

1bot,B2B2Bx

V

L1x

V

Ly

=

bottom operating line

top operating line

2bot,B2

B2

B x1VLx

VLy

=


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x ,bot1

x

1bot,B1

B1

B x1VL

xVL

y

=

x ,bot2

x

1bot,B2

B2

B xVL1x

VLy

=

x ,bot2

Partial water miscibility


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Partial water miscibility Partially miscible

system of organicand water form asingle phase only

at very high, orvery low waterconcentrations.

Water is the morevolatilecomponent insuch systems.

dry organic

organic phase

wate

rphase

feed



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dry organic

organic phase

wate

rphase

feed

iquid phase mole fraction water

vapor

phase

mole

fraction

water



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Partial water miscibility In each phase,

Raoult's can beapplied tomiscible

materials, whileHenry's can beapplied to thenonmiscible.

aqueous phase

organic phase

dry organic

organic phase

wate

rphase

feed

( ) -aaaa xVPp = a-ooo xHp =

( ) oooo xVPp = oaaa xHp =



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Partial water miscibility Equate partial

pressures of thesame phase, solvefor Henry's

constant: H calculated from known

solubilities d ry org an ic

org an ic p h ase

w aterp h a se

feed( )

oa

-aaaa

x

xVPH

= ( )ao

-oooo

x

xVPH

=

( ) -aaaa xVPp = a-ooo xHp =( ) oooo xVPp = oaaa xHp =



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Partial water miscibility Estimations of of

water in organicphase:

d ry org an ic

org an ic p h ase

w aterp h a se

feed

( )( )( ) oao

aaa

o

aoo,a xVP

xVPVPH

==

( )( )

( )( )ooo

aaa

oato

aata

ooo

oaaoo,a

xp

xp

xpp

xppxyxy

==

=

( ) oooo xVPp = oaaa xHp =( ) -aaaa xVPp = a-ooo xHp =

Steam Distillation


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Steam Distillation Steam added directly to distilling

organic mixture to reduce therequired temperature and to keepsuspended any solids that may bepresent.

Separation of volatiles fromnonvolatiles.

Process results in a pseudo-binary

distillation with the water and volatileorganics forming a heterogeneousazeotrope.

Common in purification of essential oils ,coal or anics waste solvent

Batch Steam Distillation


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Batch Steam Distillation

Continuous Steamll


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Distillation

w ater

feed

vo la tile o rg an ic

steam

w ater

o rg an ics

Steam Distillation


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Steam Distillation With two liquid phases present and in

equilibrium, compositions of the liquidphases are fixed by their mutualsolubilities.

As the amount of aqueous or organicphase is increased, phaseconcentrations do not change.

Since each phase exerts its own vapor

pressure, the vapor composition willbe constant regardless of the averageliquid composition.

A heterogeneous azeotrope results.

Steam Distillation


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Steam Distillation

Water and organic phases exertseparate vapor pressures on thetotal pressure:

Consider the case where 1 of theorganics in the mixture is a volatile species:

Liquid phase compositions set byequilibrium. When total pressure isfixed, temperature is set (i.e.,bubble point calculation), and

toa ppp =+

( ) ( ) taaaovo pxVPxVP =+

tii ppy =

Steam Distillation


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Steam Distillation

Ratio of volatile organic to water in thevapor is

If several volatile organics exist in theorganic phase, y v,o and p v,o are the

sums of the respective values for allthe organics. The total moles of steam required is n w

plus the amount condensed to heat

( )( ) o,vot

o,vo

o,vt

o,v

a

o,v

a

o,v

a

o,v

xVPpxVP

ppp

pp

yy

nn

==== tii ppy =

Complex ternary distillation


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systems A distillation curve is a plot of mole

fractions on every tray fordistillation at total reflux.

Consider column numbered from topdown Bubble point calc

at every stage Total reflux operating line

Solution at every stage

( ) 1xx,p, TK yc

1i

j,i j,ii

c

1i

j,i ====

1 j,i j,i xy =

( )=

= c

1i j,iref i

j,iref i1 j,i

x

xx

Residue Curves


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Residue Curves

A residue curve is a triangulardiagram that displaysconcentrations for a 1-stagebatch distillation operated todryness f(Nstage ).

Residue curves follow the liquidresidue composition in the still.

Different residue lines result fromdifferent starting compositions. Acollection of these curves for agiven ternary system is called a

Residue Curves


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Residue Curves

During distillation, molar liquid holdup Hdrops.

Unsteady state mass and component

balances: where V is molar rate

at which vapor leaves Rearrange

System of i ODEs must be solvesimultaneously

For constant , recursion relations can

VdtdH = ( ) ii Vydt

Hxd =

( )( )iii yxHtV

dtdx =

( )

+=

=+

c

1ik,iref ik,iref ik,ik,i1k,i xxxhxx


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A ternary residue map of a heterogeneous system

viewed as three binary

Txy diagrams


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eatures of a esidue curve map

Residue Map Characteristics


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p

If we assign direction of the residuecurves as from the startingcomposition to the ending

composition, then the arrow oneach curve points from a lowerboiling component or azeotropeto a higher boiling component orazeotrope .



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p

The presence of azeotropes cancreate distillation boundaries which cannot be crossed by a residuecurve.Distillation boundaries represent theresidue curve on which the light orstarting residue composition is a

lower boiling pure component orazeotrope and the heavy or endingcomposition residue is a higher purecomponent or azeotrope.



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p

Any given pure component point orazeotrope will be connected to somebut not all other pure component

points and azeotropes on the graph. Those that are connected formdistillation boundaries. Theseboundaries are thermodynamic innature.

Residue Map terminologyN d R id b i d d


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p gy Node : Residue curves begin and end at

nodes. Stable node : The component or azeotrope

with the highest boiling point in the region.All the residue curves in the region point to

(terminate) at this point. Unstable node : The component or

azeotrope with the lowest boiling point inthe region.

Saddle : Residue curves move toward andthen away from saddles. Pure componentsand azeotropes which have a boiling pointbetween the stable and unstable nodes are

Residue curvesT f t ti i t f


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Types of stationary points of three-component mixtures: (a) 1 component stablenode, (b) 1 component unstable

node, (c) 1 component saddle, (d) 2-component stable

node, (e) 2-component unstable

node, (f) 2-component saddle, (g) 3-component stable

node, (h) 3-component unstable

node

Residue curvesR id b d


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Residue-curve maps can be used to

make preliminary estimates of regions of feasible productcompositions for distillation of non-ideal ternary mixtures.

Residue curvesP d t i d t i d b


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Product regions are determined bysuperimposing a column material balanceon the curve map diagram.

If a straight line is drawn that connectsdistillate and bottoms compositions, that

line must pass through the feedcomposition at some intermediate point tosatisfy overall and component materialbalances.

For such a material balance line, thedistillate and bottoms compositions mustlie on the same residue curve.

S

ever Rule

= /F 100 kmol hr


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F

/F 100 kmol hr= /S 52 kmol hr

M

152100

15252

D

B

feasible product regions, zeotropicsystems:


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H

L I

systems:i. Find the limiting distillate

composition point for theregion. Draw a linefrom this point through thefeed composition, to theopposite sideof the map. This pointrepresentsthe bottoms composition withthe lowest amount of low boiler possible forthe limiting distillatecomposition(material balance line M 1).

F

M1

feasible product regions, zeotropicsystems:


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H

L I

systems:ii. Find the limiting bottoms

composition point for theregion. Draw a linefrom this point, through thefeed composition, to theopposite sideof the map. This pointrepresentsthe distillate composition withthe lowest amount of highboilerpossible for the limitingbottoms composition(material balance line M 2).

F

M1

M2


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feasible product regions,azeotropic systems


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azeotropic systemsFor azeotropic systems with distillation

boundaries, a feasible product region can befound for each region.


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ernary

e t e r o g e n e o u sA ze o tro p e

/ ,Ethanol Water using Tolueneentrainer


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Ethanol/Water withToluene entrainer


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Extractive Distillation


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used for theseparationof azeotropesand close-boiling

mixtures. solvent is

added tothe

column, forwhich oneof thecomponents (B) isselectivel

1recycleso lvent

AProduct

2

m ake upsolven t

fe ed

BProduct

Azeotropic Distillation w/ addedSolventh azeotrope


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Solvent When ahomogeneousazeotrope isformed, addedsolvent orentrainer canbe used to

produce abinary orternaryazeotrope whichcan be used toseparate themixture.

The exact natureof the flowsheetdepends on theequilibrium

behavior of the

azeot opic

column

stripper

B

feed

A

azeotropephase

separation

makeupentrainer

Reactive DistillationWh i i l h


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When reactions occur in a column, the

mass and energy balances must bemodified to include reaction terms. Often used to separate products

simultaneously during chemicalreaction to drive an equilibriumreaction in the direction of theproducts.

Reactive DistillationCA DA DCBA ++


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volat i l

product

feed

CAC

b le ed

-onvolat i l

product

feed

DAb le ed

D

& D-on

volat i le

B

DCBA ++C

D

A

Reactive DistillationA l b l f t j i


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A general mass balance for stage j is

where the reaction term r j is positive

for product components of thereaction. A rate law must be substituted into this

equation.

j j j1 j1 j1 j1 j j j j j rzFxLyVxLyV +=+


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1

m

2

1

nD

+m 1

B

.e cti fy ing s ec

.tr ipping sec eed plate


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d ll l d h f f l l f
http://en.wikipedia.org/wiki/Essential_oilhttp://en.wikipedia.org/wiki/Essential_oilhttp://en.wikipedia.org/wiki/Essential_oil


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Steam distillation is employed in the manufacture of essential oils , for,instance perfumes . ,In this method steam is passed through the plant material

.containing the desired oils It is also employed in the synthetic procedures.of complex organic compounds Eucalyptus oil and orange oil are obtained by.this method on the industrial scale

Steam distillation is also widely used in petroleum refineries andpetrochemical " ".plants where it is commonly referred to as steam stripping

Other industrial uses of steam distillation include the production of consumer food products such as sprayable or aerosolized condiments such as sprayable mayonnaise

thestrtedpofthtliid v a p o u r p r e s s u r e o f a n a g i t a t e d m i x t u r e w o u l d j u s t b e t h e s u m o f t h e s e - i n o t h e r w o r d s , 1 0 1 . 3 7 k P a

o i n t o f t h e m i x t u r e o i l w h e n t h e i r v a p o u r p r e s s u r e b e c o m e s e q u a l t o t h e e x t e r n a l p r e s s u r e . N o r m a l a t m o s p h e r i c p r e s s u r e i s 1 0 1 . 3 2 5 k P a . t h a t w i t h t h e f i g u r e w e h a v e j u s t g o t f o r t h e t o t a l v a p o u r p r e s s u r e o f a m i x t u r e o f w a t e r a n d p h e n y l a m i n e a t 9 8 C . I t s t o t a l v a p o u r

i s f r a c t i o n a l l y h i g h e r t h a n t h e n o r m a l e x t e r n a l p r e s s u r e . n s t h a t s u c h a m i x t u r e w o u l d b o i l a t a t e m p e r a t u r e j u s t a s h a d e l e s s t h a n 9 8 C - i n o t h e r w o r d s l o w e r t h a n t h e b o i l i n g p o i n t o f p u r e 0 C ) a n d m u c h l o w e r t h a n t h e p h e n y l a m i n e ( 1 8 4 C ) .
http://en.wikipedia.org/wiki/Essential_oilhttp://en.wikipedia.org/wiki/Essential_oilhttp://en.wikipedia.org/wiki/Perfumeshttp://en.wikipedia.org/wiki/Perfumeshttp://en.wikipedia.org/wiki/Eucalyptus_oilhttp://en.wikipedia.org/wiki/Orange_oilhttp://en.wikipedia.org/wiki/Oil_refineryhttp://en.wikipedia.org/wiki/Petrochemicalhttp://en.wikipedia.org/wiki/Petrochemicalhttp://en.wikipedia.org/wiki/Oil_refineryhttp://en.wikipedia.org/wiki/Orange_oilhttp://en.wikipedia.org/wiki/Eucalyptus_oilhttp://en.wikipedia.org/wiki/Perfumeshttp://en.wikipedia.org/wiki/Essential_oil


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phenylamine 7.07 kPawater 94.30 kPa

o u r p r e s s u r e o f t h e m i x t u r e t h a t t h e m i x t u r e i s b e i n g a g i t a t e d , t h e n b o t h o f t h e l i q u i d s w i l l b e i n e q u i l i b r i u m w i t h t h e i r v a p o u r s . T h e t o t a l v a p o u r p r e s s u r e i s t h e n

e s u m o f t h e i n d i v i d u a l v a p o u r p r e s s u r e s :

p o r e f e r s t o t h e s a t u r a t e d v a p o u r p r e s s u r e o f t h e p u r e l i q u i d . a t t h i s i s i n d e p e n d e n t o f t h e a m o u n t o f e a c h s o r t o f l i q u i d p r e s e n t . A l l y o u n e e d i s e n o u g h o f e a c h s o t h a t b o t h c a n e x i s t i n e q u i l i b r i u m

v a p o u r . p l e , p h e n y l a m i n e a n d w a t e r c a n b e t r e a t e d a s i f t h e y w e r e c o m p l e t e l y i m m i s c i b l e . ( T h a t i s n ' t a c t u a l l y t r u e , b u t t h e y a r e n e a r e n o u g h e t o b e u s a b l e a s a n e x a m p l e . ) t h e s a t u r a t e d v a p o u r p r e s s u r e s o f t h e t w o p u r e l i q u i d s a r e :

t ea m d is ti ll at io n is a special type of distillation (aseparation process ) for temperature sensitive materials like naturalaromatic .compoundsMany organic compounds tend to decompose .at high sustained temperaturesSeparation by normal distillation would then not be an option so water
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,Separation by normal distillation would then not be an option so wateror steam .is introduced into the distillation apparatus By adding water

,or steam the boiling points ,of the compounds are depressed allowing them,to evaporate at lower temperatures preferably below the temperatures at.which the deterioration of the material becomes appreciable If the

,substances to be distilled are very sensitive to heat steam distillation can also be combined with vacuum distillation . After distillation the

, -vapors are condensed as usual usually yielding a two phase system of, .water and the organic compounds allowing for simple separation

Principle When a mixture of two practically immiscible liquids is heated while being

,agitated to expose the surfaces of both the liquids to the vapor phase each constituent independently exerts its own vapor pressure as a function of

. ,temperature as if the other constituent were not present Consequently thef h h l i B ili b i h h f
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.vapor pressure of the whole system increases Boiling begins when the sum ofthe partial pressures of the two immiscible liquids just exceeds theatmospheric pressure ( ). ,approximately 101 kPa at sea level In this way many organic compounds insoluble in water can be purified at a temperature well

. ,below the point at which decomposition occurs For example the boiling point of bromobenzene ,is 156 C and the boiling point of water is 100 C

. ,but a mixture of the two boils at 95 C Thus bromobenzene can be easily.distilled at a temperature 61 C below its normal boiling point

Applications Steam distillation is employed in the manufacture of essential oils , for,instance perfumes . ,In this method steam is passed through the plant

.material containing the desired oils It is also employed in the synthetic.procedures of complex organic compounds Eucalyptus oil and orange oil are

.obtained by this method on the industrial scale Steam distillation is also widely used in petroleum refineries and

petrochemical " ".plants where it is commonly referred to as steam stripping Other industrial uses of steam distillation include the production of consumer food products such as sprayable or aerosolized condiments such as

.sprayable mayonnaise

h V l til A id Still i l t ifi t th i i d t f
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,he Volatile Acid Still is a glass apparatus specific to the wine industry forthe etermination of volatile acids .in wine by steam distillation Our

standard glass VA still includes an aspirator pump to suck the sample out, .after completion of the analysis allowing for rapid cycling of samples Its precursor was the glass Cash Still and many people refer to these stills

" " " ". ,generically as Cash still or RD80 For historical interest see our notes on the istory of the VA Still . &Adams Chittenden Scientific Glass

,manufactures both the VA Still and Cash Still offering an exceptionally high, ,quality product with a new m pr ov ed c or ds et nd connector , and a large

, .capacity condenser at competitive prices We have been making VA Stills and. ;Cash Stills our entire glassblowing careers We are proud of our stills they" " .have a high Wow factor and demonstrate our skills and quality For

,instructions on setup and operation see the Instructions ." " We were entertained to hear a SoundClip on NPR's Talk of the Nation on

earing a Wine's Acidity .featuring the sound of the VA Still Thanks to.Patrick Taylor of Cuneo Cellars for permission to use his words and sounds
http://www.adamschittenden.com/213Why.phphttp://www.adamschittenden.com/214History.phphttp://www.adamschittenden.com/212Improvements.phphttp://www.adamschittenden.com/212Improvements.phphttp://www.adamschittenden.com/215AdamsChittendenVAInstructions.phphttp://www.adamschittenden.com/215AdamsChittendenVAInstructions.phphttp://www.npr.org/templates/story/story.php?storyId=5581768http://www.npr.org/templates/story/story.php?storyId=5581768http://www.adamschittenden.com/215AdamsChittendenVAInstructions.phphttp://www.adamschittenden.com/212Improvements.phphttp://www.adamschittenden.com/212Improvements.phphttp://www.adamschittenden.com/212Improvements.phphttp://www.adamschittenden.com/214History.phphttp://www.adamschittenden.com/213Why.php

Documents

PP311 Distillation