Documents

Exp.07_Spray_Dryer.doc

Description
METU Chem. Eng. Dept. Ch.E. 420 Chem. Eng. Lab III EXPERIMENT 7 - SPRAY DRYER OBJECTIVE The objective of this experiment is to evaluate the performance and drying characteristics of a laboratory scale spray dryer. PRELIMINARY WORK a) On the basic concepts 1. Read the attached information on the basics of drying and psychometry and answer the questions below. 2. Find the relative humidity of air with Td = 50C, Tw = 30C Td = 60C, Tw = 38C Td = 100C, Tw = 55C where Td and Tw are the dry
Categories
Published
of 11
All materials on our website are shared by users. If you have any questions about copyright issues, please report us to resolve them. We are always happy to assist you.
Related Documents
Share
Transcript
  METU Chem. Eng. Dept.Ch.E. 420 Chem. Eng. Lab IIIEXPERIMENT 7 - SPRAY DRYER ! ECTI#E The objective of this experiment is to evaluate the performance and dryingcharacteristics of a laboratory scale spray dryer. PRELIMINARY $R%a&  On the basic concepts1.Read the attached information on the basics of drying and psychometryand answer the questions below.2.ind the relative humidity of air with T d  ! # ° $%T w  ! &# ° $T d  ! '# ° $%T w  ! &( ° $T d  ! 1## ° $%T w  ! ° $where T d  and T w  are the dry) and wet)bulb temperatures.&.ind the humid volume and humid enthalpy of air for the conditions given inpart 2. *hat additional information do you have to supply for the enthalpyvalues+,.*hat are the parameters affecting the equilibrium moisture in the dryingoperations+ .*hat are the advantages and the disadvantages of spray drying+ b&  On the experiment1.The equipment to be used in this experiment is the -ab)lant /odel 0)#,spray dryer located in room number 1# on the first floor of the  3loc4%The 5nit Operations -aboratory building. 0tudy the equipment carefullywith the help of 0pray ryer /anual which can be obtained from your supervisor and familiari6e yourself with its operation.2.s4 for instructions on the choice% availability% or the advanced preparationthat needs to be done for the feed solution or slurry that will be dried. 171#  /8T5 $hem. 8ng. ept.$h.8. ,2# $hem. 8ng. -ab 999 8xperiment :0pray rier  &.repare a data sheet. PERATIN ;0ee 0pray ryer /anual p.&%<% ig.2% ig. =1.$onnect the spray drier to the electrical main supply. /ain connectionindicator light illuminates ;ig. ;c==.2.To feed the pump feed tube ;ig.2 ;1#== to the peristaltic pump head ;ig.2;<== first% remove the clear plastic and metal covers from the pump head.ress the main on7off switch ;ig. ;d== followed by the pump switch ;ig. ;j==and with the pump rotor turning very slowly% push the tubing between therollers ;ig.2;12== until it is correctly positioned between the rollers and thepump head inner wall. 0witch off the pump. ;Ta4e care not to trap your fingers.=&.*ait for a few seconds to allow inlet ;ig. ;a1== and outlet ;ig. ;a2==controller7indicator to settle at approximately ambient temperature.,.ill the sample bottle ;ig.2 ;11== with distilled water. lace pump feed tubeinto sample bottle. .0witch on first the blower ;ig. ;e== and then the heater ;ig. ;g==.'.0witch on compressor ;ig. ;h== and open compressor pressure setting;ig. ;i== to full.:.0tart ta4ing inlet and outlet air temperatures as a function of time until therequired inlet air temperature ;set temperature= is reached and uniform outletair temperature is attained.(.0witch on pump to feed distilled water. 0uitable spraying rate% i.e.% the rate atwhich the sprayed liquid cannot be seen to be hitting the chamber walls% isachieved by means of pump speed control ;ig. ;4==. low rate is determinedusing the scaled sample bottle as m-7s or m-7min. eed distilled water untilsteady state condition is reached ;uniform outlet temperature is obtained= andvariation in airflow is not too much. $ontinue ta4ing inlet and outlet air temperature data while feeding the distilled water. 271#  /8T5 $hem. 8ng. ept.$h.8. ,2# $hem. 8ng. -ab 999 8xperiment :0pray rier  <.0tart pumping the feed solution prepared before. ried powder should beobserved spiraling down the cyclone ;ig.2 ;:== into the sample collectionbottle ;ig.2 ;(==. Ta4e inlet and outlet air temperatures.1#./easure% by means of an anemometer% the air velocity at the air exit.11.Record% using a psychrometer% the wet) and dry)bulb temperatures of the inletand outlet air. ;s4 your supervisor for instructions to use anemometer andpsychometer.=12.fter terminaton of sending the feed solution% feed the dryer again withdistilled water% now to clean pump feed tube completely.1&.*eigh the solid material collected in the sample collection bottle. STPPIN' T(E PERATIN AND CLEANIN' 1.0witch off the pump . 2.0witch off the heater% compressor% and blower% in the given order.&.0witch off the mains connection.,.Remove the product collection tube ;ig.2 ;'== from the cyclone. .Remove the sample bottle from the cyclone.'.Open the bottom clamp which connects the main chamber and cyclone.isconnect the cyclone.:.Open the top clamp and disconnect the main chamber.(.$lean all these parts by washing with water.<.ump feed tube should be removed from the peristaltic pump headfollowing the same but opposite procedure as in ;2= in operation part. CALCULATINS 1.lot inlet and outlet air temperatures as a function of operating time.2./a4e a material balance for water.&.ind the percent recovery of the solid based on total solid input. &71#  /8T5 $hem. 8ng. ept.$h.8. ,2# $hem. 8ng. -ab 999 8xperiment :0pray rier  ,./a4e an energy balance during the steady state operation. etermine theenergy input by the hot air and all the energy outputs. .efine an appropriate thermal efficiency for this spray drying apparatusand calculate it. RE)ERENCES 1.erry% R.>.% ?reen% .*.% /aloney% @.O.% AerryBs $hemical 8ngineersB>andboo4C% 'th ed.% pp.():#% 2#) 1 to 2#) (% /c?raw)>illD Eew For4%1<(,.2.oust% .0.% *en6el% -..% $lump% $.*.% /aus% -.% nderson% -.3.%Arinciples of 5nit OperationsC% pp.&,#)&,<% *ileyD E.F.% 1<'#.&.Treyball% R.8.% A/ass Transfer OperationsC% &rd ed.% pp.' ):1'% /c?raw)>illD Goga4usha% To4yo% 1<(#.,./c $abe% *.-.% 0mith% @.$.% >arriot% .% A5nit Operations of $hemical8ngineeringC% th ed.% pp. :':)(#'% /c?raw)>ill Goga4ushaD To4yo% 1<<&. ./asters% G.% A0pray rying >andboo4C% &rd ed.% pp. 1) 2% :,)1#:% ?eorge?odwinD -ondon% 1<:<. S(RT NTES N DRYIN' AND SPRAY DRYIN' The term drying refers generally to the removal of moisture from a substance. solution can be dried by spraying it in fine droplets into a hot% dry gas% whichresults in evaporation of the liquid% but evaporation of the solution by boiling in theabsence of a gas to carry away the moisture is not ordinarily considered a dryingoperation. E*+,,b,+m The moisture contained in a wet solid or liquid solution exerts a vapor pressure toan extent depending upon the nature of the moisture% the nature of the solid% andthe temperature. 9f then a wet solid is exposed to a continuous supply of freshgas containing a fixed partial pressure of the vapor p% the solid will either losemoisture by evaporation or gain moisture from the gas until the vapor pressure of  ,71#

Economics project

Jul 23, 2017

Lecture 2

Jul 23, 2017
We Need Your Support
Thank you for visiting our website and your interest in our free products and services. We are nonprofit website to share and download documents. To the running of this website, we need your help to support us.

Thanks to everyone for your continued support.

No, Thanks