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SIMPLE DISTILLATION
Aim:To verify Rayleighs equation for the given binary system.
Apparatus required:
Simple distillation setup, measuring jar, specific gravity bottle and beaker.
Theory:In simple distillation, a batch of liquid is charged to a kettle or flask fitted ith some
sort of heating device. the charge is boiled sloly and the vapors are ithdran as rapidlyas they form in a condenser here they are liquefied and the distillate collected in the
receiver the vapor leaving the flask at any time is in equilibrium ith the liquid in the flask,but since the vapor is richer in the more volatile component , the composition of liquid and
vapor are not constant .the first portion of the distillate ill be the richest in the more
volatile component and as distillation proceeds ,the vapori!ed product become leaner, thedistillate can therefore be collected in several separate batches to give a series of distilled
product of various purity.
Rayleighs equation is"
( )( )
=F
W
x
x XY
dXWF
*/ln
Procedure:
#$ Take %&& ml of component ' ('cetone$ and #&&ml of component ) (*ater$ in thedistillation flask and heat over a heating matter.
%$ +arry out the distillation until %-
rd
of the miture get distilled.-$ +ollect the distillate in conical flask.
/$ 0ind out the volume of distillate.1$ +ool the residue to room temperature.
2$ 0ind out the volume of the residue.3$ 0ind out the density of residue using specific gravity bottles.
Observation:
4olume of 'cetone taken 5 ml
4olume of *ater taken 5 ml
6ensity of 'cetone 5 gcc
6ensity of *ater 5 gcc
*eight of empty specific gravity bottle 5 g
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Tabuation: !
"aibration "hart:
S.7o.
4olume in ml *eight in g 8ole fraction of Refractive
IndeSpecific
gravity of 'cetone
'ceton
e*ater
Sp. gr. )ottle
9 Sample
Sampl
e'cetone *ater
#.
%.
-.
/.
1.
2.
3.
:.
;.
#&.
##.
"acuation:
*eight of 'cetone 5 (4olume of 'cetone$ < (6ensity of 'cetone$
*eight of *ater 5 (4olume of *ater$ < (6ensity of *ater$
8oles of 'cetone taken (*$ 5 (*eight of 'cetone$ (8olecular *eight of 'cetone$
8oles of *ater taken(6$ 5 (*eight of *ater$ (8olecular *eight of *ater$
Total 8oles 5 8oles of 'cetone 9 8oles of *ater
8ole 0raction of 'cetone (=0$ 5 8oles of 'cetone Total 8oles
8ole 0raction of *ater 5 8oles of *ater Total 8oles
4olume of Residue +ollected 5 ml
4olume of 6istillate +ollected 5 ml
6ensity of Residue 5 gcc
Specific >ravity of Residue 5 6ensity of Residue 6ensity of *ater
0rom the graph Specific >ravity (?@ais$ vs. 8ole 0raction of 'cetone (=@ais$,
8ole fraction of 'cetone in Residue, =5
'verage 8olecular *eight of Residue 5 A=
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Residual liquid in gmols (*$ 5
Tabuation: #
4CD data for 'cetone@*ater system"
(Refer E+hemical Dngineering FandbookG by Robert. F Herry 6on >reen, 2th
edition, Hage7os" #-.##@#-.#% #-.%#$
S.7o.
= ?< ?< @ = #(?< @ =$
#.
%.
-.
/.
1.
2.
3.
:.
;.
#&.
##.
#%.
$eri%ication: Rayleighs equation is
( )( )
=F
W
x
x XY
dXWF
*/ln
0rom graph = (y@ais$ vs. #(?< @ =$ (@ais$, find the area under the curve beteen
=0and =*. That is,
RFS 5
( ) F
W
x
x XY
dx*
5
0rom the calculated data, find CFS 5 ln (0*$ 5
+heck CFS5RFS
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Anaytica Method :
ln (0*$ 5 ln A(6J R$(6J 0$B
&esut:
Thus Rayleighs equation is verified.
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DI''(SI$IT) MEAS(&EMENT
AIM
To determine the diffusion coefficient of organic vapor in air at various temperatures.
APPA&AT(S
6iffusivity cell, stop atch.
T*EO&)
Some liquid K'K is taken in a diffusivity cell. The concentration of liquid vapour just
above liquid surface is the vapour pressure of the liquid. If a stream of air is being dran
along the top edge of the cell, the concentration of liquid vapours there is determined by the
amount of liquid vapour present in atmospheric air. The diffusion that occurs in this case is
diffusion of acetone ('$ through stagnant air ()$. Since the height of the liquid in the cell is
not maintained constant, a Hseudo Steady State diffusion model may be used.
'ccording to this model ,
DAB=RT
0aPBM(X2X
0
2 )
2P MA t(PA1PA 2)
*here
6')5 6iffusivity of ' in stagnant ), m%sec.
5 6ensity of diffusing liquid, Lgm-
R 5 Mniversal gas constant, :-#/ NLg mol oL
T& 5 Operating temperature,oL
H)8 5 log mean vapour pressure, 7m%
H 5 Total pressure, 7m%
8' 5 8olecular eight of diffusing liquid, LgLg mole
H'# 5 4apour pressure at point #, 7m%
H'% 5 4apour pressure at point %, 7m%
t 5 Time of diffusion, seconds
= =& 5 0inal and initial heights of the liquid, m
DES"&IPTION:
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The equipment consists of a T tube made of glass, placed in ater bath. *ater bath is
provided ith heater. Temperature of the bath is controlled by the digital temperature
controller. Stirrer is given to maintain the constant temperature bath. 'ir pump is provided
to supply the air, passed through the tube. +hange in the liquid level is observed by the
travelling microscope ith sliding vernier scale.
P&O"ED(&E
o 0ill the ater bath ith ater -/thof its capacity.
o Set the ater bath temperature appro 1&P+
o Sitch O7 the heater and stirrer
o *ait till the bath attains the set temperature. 7ote the steady temperature of
the bath
o 0ill the T@tube ith acetone solution up to to centimeters of the capillary leg.
o 7ote don the initial height of liquid in the capillary
o 8ake the connection ith air pump and allo a gentle current of air to flo
over the capillary.
o Record the height of liquid in the capillary after every -& min.
o Repeat the eperiment for different ater bath temperatures.
o Repeat the eperiment for different organic liquids like" ethanol, toluene and
heane and ++l/.
DATA:
Total pressure H 5 #.-%1 Q #&1 7m%
Real gas constant R 5 :.-#/ (7 m%$ J m- mole@L
8olecular eight of the liquid 8'5 gmole
Hartial pressure of liquid at the top of the tube H'%5 & 7m%
+onstant ' 5 #1.:/
+onstant ) 5 %3;&.:
+onstant + 5 %%2./2
O+SE&$ATIONS
T 5
=&5
O+SE&$ATION TA+LE
Sl.7o. t (min$ = (cm$
"acuation:
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To calculate the property of organic liquid at temperature TP+ from data book.
' 5 kgm-
5 =&& (m$ (initial height of liquid at t#5 &$
5 =#&& (m$
t#5 t Q2& (sec$
T& 5 %3- 9 T (L$
H'# , e( A B
C+T)
(mm Fg$
H'# ,H'# (mmFg$= #--.- (7m%$
H)# ,H-H'#
H)% , H-H'%
H)8 ,(H)% J H)#$ (ln (H)%H)# $
DAB=
R T0P
BM a (X2X02)
2P MA t(PA 1PA2 )
"acuation Tabe:
S.7o t#(sec$ (cm$
&ES(LTS
6iffusivity of the given organic liquid in air is calculated.
'O&"ED D&A'T T&A) D&)E&
AIM
To study the drying characteristics of a solid under forced draft condition and
(#$ To calculate the rate of drying
(%$ To calculate the critical moisture content
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(-$ To plot the graph of time vs moisture content
(/$ To plot the graph of time vs rate of drying
(1$ To plot the graph of moisture content vs rate of drying
(2$ To plot the graph of mass velocity of air vs rate of drying
(tiities required:
0orced draft tray dryer, 6rying solids" sandasbestossilica.
T*EO&)
In many cases, drying of materials is the final operation in the manufacturing
process, carried out immediately prior to packaging or dispatch. 6rying refers to the final
removal of ater, and the operation often follos evaporation, filtration or crystalli!ation.
6rying is carried out for one or more of the folloing reason"
#. To reduce the cost of transport
%. To make a material more suitable for handling
-. To provide definite properties
/. To remove moisture this may otherise lead to corrosion.
6rying of solids is considered to occur in to stages, a constant rate period folloed
by a falling rate period. In the constant rate period, the rate of drying corresponds to the
removal of ater from the surface of the solid. The falling rate period corresponds to the
removal of ater from the interior of the solid. The rate in either case in dependent on"
0lo rate of air, The solid characteristics and Tray material.
The drying rate of a solid is a function of temperature, humidity, flo rate and
transport properties of drying gas. The rate of drying can be determined for a sample of a
substance by suspending it over an electronic balance in the duct. The eight of the drying
sample can then be measured as a function of time.
Cet *s is mass of solid ' is drying area, is moisture content at any time t. The rate of
drying is given as"
7 5 @ (*s Q $ (' Q t$
*here is moisture content difference and t is time difference.
P&O"ED(&E:
o Hrepare a miture of knon eight of sand and ater. (-&@1&U of ater$
o 0ill the tray ith above prepare miture and note don the sand eight.
o Set the temperature of bloer, sitch on the heater and start the bloer.
o 'djust the valve 4# and set the flo rate of air.
o *hen the desired conditions of temperature and air velocity are reached
(appro #&@#1 min$ put tray in the drying chamber.
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o Msing stop atch check the balance reading at every -@1 minutes interval.
o +ontinue the eperiment till three consecutive reading are unchanged.
o Repeat the eperiment for different solid material and different air flo rate.
O+SE&$ATIONS:
Data: 'rea of the tray ' 5 m%
6iameter of the orifice do5 &.&%2 m
6iameter of pipe dp5 &.&1% m
+oefficient of discharge +d5 &.2
T 5 P+
* 5 kg
*s5 kg
TA+(LA& "OL(MN:
S.7o t (sec$ (kg$ R (m$
"acuations:
=t5 *J **
* 5 kg (0inal value of $
=< 5 *J *< *
=< 5 =tJ =< = 5 =nJ =n9#
t 5 tn9# J tn (n5#,%,-V.$
"acuation Tabe:
S.7o t (min$ t (min$ =
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Hlot the graph of t vs .
75 5 @ (*sQ $ (' Q t$ kg sec m%
a&5 W/ Qdo2
m%
ap5 W/ Qdp2
m%
F 5 R (a@#$ m
Xa5 +dQ
ao ap
ap2
ao2 Q 2g H m-sec
> 5 XaQ a kgsec
S.7o 7 (kgsec m%$ > (kgsec$ t (sec$
Hlot the graph of > vs 7
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Hlot the graph of t vs 7
Hlot the graph of 7 vs and determine =c
&ES(LT
SIMPLE LEA"*IN.
AIM
To plot the theoretical and actual recovery 4s solvent feed ratio.
APPA&AT(S
8easuring jar, conical flask, burette, pipette, beaker and stirrer
T*EO&)
Ceaching is the process of removal of a solute or solutes form a solid by the use of aliquid solvent. It originally refers to the percolation of liquid through a fied bed, but it is
also used to mean solid liquid etraction generally. The presence of a solid phase
distinguishes it from liquid etraction. To steps involved in solid liquid etraction are "
#. +ontact of solid and solvent to effect transfer of solute to the solvent and
%. Separation of the resulting solution from the residual solid.
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0OR8MC'
?#5 4olume of etract 5 volume of 7aOF< normality of 7aOF
4olume of etract
Theoretical recovery 5 amount of solvent < #&&
'mount of solvent 9 amount of feed
Solvent to feed ratio
#. 1&1& 5 # =#5 (?# < 1- < 1& $#&&&
%. #&&1& 5% =%5 (?% < 1- < 1& $#&&&
-. #1&1& 5- =-5 (?- < 1- < 1& $#&&&
/. %&&1& 5/ =/5 (?/ < 1- < 1& $#&&&
1. %1&1& 51 =15 (?1 < 1- < 1& $#&&&
U 'ctual recovery 5 (= 1$ < #&&.
P&O"ED(&E
'bout /1 gm of sand and 1 gms of oalic acid and #&& ml of distilled ater are taken
as feed in each of the five beakers. 'bout 1& ml of ater is added to first beaker and
stirred ell, alloed to settle. 0rom the supernatant solution #& ml is pipetted out and is
made upto #&& ml. #& ml of this solution is used for titrating against &.% 7 7aOF. Sodium
hydroide is standardised using &.#7 oalic acid. Then #&& ml of ater is added to the
second beaker and the same procedure is repeated. Cikeise #1& ml, %&& ml of distilled
ater is added respectively to third, fourth and fifth beakers and the same procedure are
repeated.
0rom this, actual recovery, theoretical recovery and solvent feed ratio are calculated.
' graph of percentage actual recovery and percentage theoretical recovery 4s solvent feed
ratio as plotted.
STANDA&DISATION O' SODI(M *)D&O/IDE:
4olume of
sodiumhydroide, ml
)urette reading in ml 4olume of Oalic
acid, mlInitial 0inal
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4olume of Oalic acid 5
7ormality of Oalic acid 5
4olume of Sodium Fydroide 5
7ormality of Sodium Fydroide 5
)ottle
number
4olume of
etract
)urette readings in ml 4olume of
7aOF (ml$
7ormality of
etract 7Initial 0inal
#
%
-
/
1
%&
%&
%&
%&
%&
&ES(LT
The theoretical, actual recovery 4s solvent feed ratio as calculated and a graph as
also dran.
?
=
U
Recovery
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"O(NTE& - "(&&ENT LEA"*IN.
AIM
To study the principles of leaching and to compare the results obtained by leaching
the given sample.
APPA&AT(S
+onical flask, pipette, burette, measuring jar, glass rod and beaker.
T*EO&)
Ceaching is a process of removing solute or solutes from a solid by the use of liquid
solvent. It is originally referred to percolation of the liquids through a fied bed. )ut it also
to mean solid @ liquid etraction generally. The presence of a solid phase distinguishes it
from liquid@liquid etraction.
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To steps are involved in solid @ liquid etraction
#. +ontact of solid and solvent to effect transfer of solute to solvent.
%. Separation of the resulting solution from the residual solid.
Ceaching may be conducted by any of the folloing methods
Single stage operation
8ulti@stage +o@current operation (parallel or cross@ current$
In single stage operation the solid feed and the fresh solvent are contacted, mied
for
Sufficient time for the solute to be transferred to the liquid phase and the solution and the
solids are separated into overflo and underflo respectively. It is rarely encountered in
industrial practice because of lo recovery of solute.
In multi stage counter@current system, fresh solvent is added into the first stage and
solid feed is added in the final stage. Mnderflo from the first stage is sent to the second
stage and so on. The same procedure is repeated in all the succeeding stages.
P&O"ED(&E
%/& gms of sand and %.1 gms of oalic acid are taken in a flask labeled # to 2. #&&
ml of ater is added to each. Then #&& ml of ater is added to flask (#$ and the contents
are shaken and alloed to settle. #&& ml of supernatant liquid is pipetted out into flask (%$.
The contents are shaken and alloed to settle, #&& ml of supernatant liquid is pipetted into
flask (-$. 'fter the contents are shaken, after settling #&& ml of supernatant liquid from
here is rejected, flask (#$ is rejected. The procedure is repeated as shon in the figure until
2thstep.
7o, %1 ml of solution, each from flasks /,1 and 2 are titrated against standard
7aOF solution. The solution of leached solids stage - is filtrated into a clean dry conical
flask. %& cc of this solution is titrated against standard 7aOF.
O+SE&$ATIONS
'mount of oalic acid taken 5
Strength of oalic acid 5
STANDARDISATION OF SODIUM HYDROXIDE
4olume of 7aOF
pipetted
)urette reading 4olume of oalic
acid usedInitial 0inal
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Strength of 7aOF 5 volume of oalic acid < strength of oalic acid 5
4olume of 7aOF
Stage 7umber 4ol. Of sample used 4ol. Of 7aOF consumed
&ES(LT
The result obtained ere compared by leaching a given feed
#. 7umber of stages used 5
%. 7umber of stages required theoretically 5
STA.E 0ISE LEA"*IN.
Aim:
To separate a solute constituent from a solid miture by stage@ise leaching.
Apparatus:
1&& ml beaker, 0unnel, 0ilter paper, Hipette, )urette, >lass rod.
"hemicas required:
Sodium carbonate, sand, 6ilute F+l, Indicator and ater.
Procedure:
Take three cleaned and dried 1&& ml beaker, it is numbered from # to -.
Into each beaker accurately eighed quantity of 1& g of sand and %& g of sodium carbonate
as taken.
'll beakers are thoroughly mied ith glass rod
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To the first beaker -&& ml of distilled ater as added. The contents are stirred ell and
alloed to settle. Similarly #1& ml of ater added to second beaker and #&& ml of ater to
the third beaker respectively.
'fter the sand particles have settled the clear supernatant liquid as decant into the
corresponding beaker.
The procedure is repeated again ith #1& ml of ater in second beaker and #&& ml of ater
in third beaker.
0inally again #&& ml of distilled ater is added to the third beaker.
%& ml of makeup solution from each beaker as titrated against standard F+l.
The amount of Sodium carbonate as calculated in each stage.
"acuation Procedure:
4olume of leached solution 4% 5 %& ml
7ormality of F+l 7# 5 # 7
Stage I"
4olume of F+l added 4# 5 ml
7ormality of leached solution 7% 5 4# Q 7# 4%
'mount of Sodium carbonate in #&&& ml of solution 5 ( Dquivalent eight Q 7ormality
Q4olume of etract$ Q #&&
U Dtraction 5 ('mount of etract'mount of feed$ Q #&&
Tabuar "oumn:
Stages 4olume of leached
solution in ml
4olume of
etract in ml
)urette reading ml 4olume of F+l
in mlInitial 0inal
&esut:
Stageise leaching eperiment as performed and percentage etraction as calculated.
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LI1(ID-LI1(ID E/T&A"TION
Aim:
To carryout liquid@liquid etraction for etracting acetic acid from ater using solvent and to
find the distribution coefficient and percentage of etraction.
Apparatus &equired:
+onical flask, Separating funnel, )urette, Hipette, 8easuring Nar
'ormuae (sed:
6istribution coefficient" Ld5 +d +n
+dJ +oncentration of etractable in organic phase+n@ +oncentration of etractable in ater phase
Procedure:
Hrepare #7 acetic acid solution and &.#7 7aOF solution. /& ml of acetic acid and %& ml
of solvent is taken in a separate flask and stirred using rotary shaker for #1 minutes. Then
the miture is alloed to separate as layers and pour it into a separating funnel. The
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bottom layer raffinate as measured and %& ml of it is pipette and titrated against 7aOF
solution. 0rom the titration value distribution coefficient and U etraction ere calculated.
"acuation procedure:
+e%ore e2traction:
#. 'mount of acetic acid in /& ml solution of #7 5 (4olume of acetic acid Q Dquivalent
eight of acetic acid Q 7ormality of acetic acid #&&&$
A%ter e2traction:
%. 7ormality of acetic acid 4# 7# 5 4% 7%
-. 'mount of acetic acid in /& ml 5 (4olume of acetic acid Q Dquivalent eight of acetic acid
Q 7ormality of acetic acid #&&&$
/. 'mount of acetic acid etracted 5
1 U of Dtraction 5 ('mount of acetic acid etracted 'mount of acetic acid in /& ml$Q#&&
2. 6istribution coefficient 5
&esut:
The distribution coefficient and U etraction of various solvents ere calculated.
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&OATA&) D&)E&
O+3E"TI$E
To study the operation of rotary dryer.
AIM
To calculate the rate of drying for different air flo rates and different air inlet temperatures.
To plot the rate of drying curve.
Theory:
In many cases, the drying of materials is the final operation in the manufacturing process,
carried out immediately prior to packaging or dispatch. 6rying refers to final removal ofater, the operation often follos evaporation, filtration or crystalli!ation. 6rying is
carried out for one of the folloing reasons.
To reduce the transportation cost
To make a material more suitable for handling, for eample soap poders, dye
stuffs, fertili!ers.
To provide definite properties, such as maintaining free floing nature of salt.
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To remove moistureY hich may otherise lead to corrosion, for eample, the drying
of coal gas or ben!ene prior to chlorination.
'lmost all drying processes involve the removal of ater by vapori!ation, thus require the
addition of heat.
The rotary dryer is a type of industrial dryer employed to reduce or minimi!e the liquid
moisture content of the material by bringing it direct contact ith a heated gas. The dryer
is made up of large rotating cylinder hich slopes slightly so that the discharge end is loer
than the material feed end is order to cover the material under gravity. 8aterial to be dried
enters the dryer as the dryer rotates, the material is lifted up by a series of internal fins
lining the inner all of the dryer. Feating option include steam, gas, oil, thermal oil, and
auillary biomass burner system.
+onsider a rotary continuous direct heat counter current dryer fed ith a nonporous
material having all moisture as unbound moisture. 's this material enters the dryer, it is
first heated to the drying temperature. It ill then pass through the length of dryer at
nearly the et@bulb temperature and theoretically at the end of the dryer, the material shall
be discharged as dry material nearly at the et bulb temperature.
Assumptions:
7O heat losses from the dryer.
Feat is applied to the material only from the air, not by conduction from the dryer
shell.
'll the moisture present is free moisture.
There is no evaporation of moisture in the preliminary heating period.
6rying proceeds at a constant et bulb temperature until desired amount of ater has been
removed. The entering air is assumed to be #&&U saturated, so its temperature needs to
be raised so as to decrease the relative saturation. This ould enable the air to absorb
moisture from the et solid feed. In turn the eiting air is more saturated than the entering
one.
0or continuous dryer at steady state operating conditions,
0(=# J =%$ 5 > (?# J ?%$
This assume that the dry gas flo > and dry solids flo 0 do not change beteen dryer inlet
and outlet. 8ass balances can also be performed on the overall gas and solids entrainment
in the ehaust gas stream.
The required solids flo rate, inlet moisture content =# and outlet moisture =& are normally
specified, and the evaporation rate and outlet gas flo are calculated.
0or batch dryer ith dry mass m of solids, a mass balance only gives a snapshot at one
point during the drying cycle and an instantaneous drying rate given by"
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m d=dt 5 > (?#J ?%$
d=dt 5 >(?# J ?%$ m
Sometimes d=dt is called rate of drying.
Description:
The set@up consists of a long resolving cylindrical shell slightly inclined toard the outlet.
The shell is fitted ith to brackets for support. 'ir from a bloer passes through a heating
chamber serves the purpose of drying agent. 'n arrangement is provided for rotating the
dryer shell connected ith electric motor and a reduction gear bo. 0lo control vale and
by@pass valve are fitted to regulate the airflo.
(tiities required:
Solid material (seeds -@1 mm$" % kg
E2perimenta procedure:
Take knon amount of the solid material and eigh it.
7o mi knon amount of ater in the solid and eigh the et solid.
Set the preheating temperature of air.
Sitch O7 the bloer and set the flo rate of air by adjust the valve 4#.
Sitch O7 the heater ait till the set point temperature is arrived.
0ill the feed hopper ith et solid.
Start the dryer in rotary motion.
'llo the et solid to flo through the dryer by starting the scre conveyor and
rotating hand heel manually.
't steady state record the manometer reading. 7ote don the air temperature at inlet Sand outlet.
Repeat the eperiment for different air flo rates.
Repeat the eperiment for different air inlet temperature.
Observation 4 "acuation:
Data:
'rea of the dryer ' m%
6iameter of orifice do &.&%2 m
6iameter of pipe dp &.&1% m
+oefficient of discharge +d &.2/
'cceleration due to gravity g ;.:# msec%
6ensity of ater and air #&&& #.%# kgm-
8olecular eight of air and ater %; #: gmole
Observations"
Z&5 kg
Z 5 kg
* 5 kg
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T 5 sec
S.7o T# (P+$ T% (P+$ T-(P+$ T/ (P+$ h# (cm$ 5
"acuations:
H=h1h
2
100(w
a1)m
a1=
4dP2 ( m2)
a2=
4do2 (m2 )
Qa= a
1a2
a12a2
2Cd2 gH
G=a Qa
A( kg/m2 sec )
= 5 Z J Z&* kg moisture kg dry solid
To calculate the humidity (y# y%$ of air at temperature (T# T%$ and (T- T/$ respectively
by psychometric chart.
y#5
y%5
?#5 y#(8 8'$ (kg of moisture kg dry air$
?% 5 y%(8 8'$ (kg of moisture kg dry air$
? 5 ?#J ?%(kg of moisture kg dry air$
7+ 5 > Q ? Q #&&& (* Q =$ (kg of moisture m%sec$
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S.7o t (sec$ 7 ( kg of moisture m%J sec$
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