The Industrial Practice of Chemical Process Engineering

7/16/2019 The Industrial Practice of Chemical Process Engineering

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Th Iduil i

hmi Egig

Smul W Bodmn

Th MJ.T s

assachuse nsue of Technology

Cambrdge assacuse ad Londo Engan


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Coyri 1968 y

The Massachuses Insie o Tchnoogy

Prined nd ond he Unid Saes o merica yThe Mae Press Coany, Yo, Psyania

A rigs rseed o art o is oo may eroducd or iized in ny or or y any meseeconic or mechanica incung oocoyingrecodg, or y any omaion soage d rerea

syse wio ermission in wrig o bie

ibary o Congrs caaog card nuber: 8-822


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Preface

With study of th engnering sciences no a oint co i th

currcua o mny acaic ngnring deptents, only lit ti is

availal or th crative applictio of thortical ntls to practicl

chicl rocssng probls. aticulr th stuy of rocss esig

and nncil valuation is ot ithr isrgr or giv ony cursory

attntion As a result th youg nginring gru rqutly ncotrs

dicutis in coing ccliat to th nviront of a corcilorgizton an i xiizing th nits which c b gnrat ro his

tchnicl ckgrou

In or to repr its stuts mor ly or th chnges o

inusti or th MI. T Cheical Engnng Dprtnt has dvlop

to specific rogrs Frst th epart's School o Chical Engin

ing Prctic oss graduate stuents to actul robls a inustri

evironnt r th dict an clos suvisio of a culty mr

This roga hs i oprtio o ov ity ys a hs rove to

a eectiv contiutor to a stunts tot acaic pinc To co

lt th ractic Schoo ogr a snior-yr synthsis cours n

rocss dsig has e vlop oessor hoas K Shoosumarizd his origin or i th vlopent of th M T rocss dsi

cours in his t "A Cous i Procss Dsig" Th ous as concive

y h s sd uon a seris o dsi cass; or each case studt isuir to dvis an aayz rocess schs tat ight ad to th

solutio of th dsig rol

Th snt t ses o comi so ascts o e Pactice School

rogra th leents o rossor Shroods casstudy approach to

sction ngiing sig It is hop that th rsult o this coatioil not only usu as a tt or acadmic ocss sig stctio ut

l also sv as a rerec oo or yog ngr arg o a

carr dus.


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iv Preface

An roductory chaper brefy describes e eracon and iner-

dependence of market reseah rocess des and financal evaluaion

funcons n commercazig a chemcal pduc. Meods of lag and

anyzg laboratory expermens of utg marke and nc nfor-maon ad of reparg and resenig a chemicl process desi are

dscussed The roduction s followed by seres of s case studes

engeerg des, ical of hose encounered by a yog engineer hsnal dusrial assmens The eed for accurate yss ad correla-ton of laboratory da s gven grea epass Secondly, he need fordevsg ceave ad paccal soutons pcessg roblems s given

some dscusson Fnally, each case llusrates metods o combinng technical and fincal nfoaon o rovde a realisc evaluaion of roposedprocess Each case s concluded i a recommeded desin as well s

suggesons for er or ha would be reured in subseque, moredeaied, design effors

grea deal of epasis as bee paced on te use of te digalcompuer e aysis nd presetation of desi probes; couter

progras are preseted for tree of te cases dscussed Tese progrs

ad oters le em hve roven o be parculay stiulag en used na "copuered classroom, " where e stude c commuicate direcly

wi e acie n preparng poons of e ext, as been assumed hae reder hs a leas some odge of e OTN cog laguage

The present voume was written e e autor seed as irecor ofhe od Brook Ston of . Ts Scool of Ceical Engeerg Pracce.

This stato s ocated t te Orgaic Cheica ivision o e erica

Caaid Coay od rk New Jersey e data used in te rearaton of Cater wee gatered by a stdet grou as a ar of a rojcta te ud rook Statio The autor s gratef to erica Caaid forts emisso o use tese data as el as for te coan's ositaity urg

te ad acadeic ears

Many dviduals have contribud subsialy o e case sues

smared s book rs of a, hs ar due o rofessor homas Sherwood ho has coninued hs dce n he nscion of cemcal

process des a M.T It as e o orgally suggested the preparaonof he prese et d Capters 2 ad 4 are based aost enirely on desi

cases deveoped by him for is process desgn courses Sincere aprecaon

s eressed o rofessor ober Yor of Coel Uversiy for his dance e ecooc evauaton of chemic projecs d for hs insctve re

vew of portos of te presen ex rofessors C J Kg and Scot yn ofe Unversty of Calfoa erkeey were knd eoug o eve e entre

e of is book Ter commets were aricuarly sgnificat vgaddtioal breadt ad me o several of e case sudies Dr oard

Kehde and is coleaes a ow Ceical Copy, dand, Michgan, veryky revewed the cases coceed wit styrene roducon te commensprovded an vauable dension to tose cases by brig o bear e kowledge d soisicaio of a ajor roducer of ree monoer rofessorGles R Cokele of Cafoa situte of Tecnogy provided vauabecommentary on e sulfur rasoaion case rofessor R G. Thore ofCoel Uversiy ornaly acquaied he autor wi some of he dffcues


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Preae v

ssited th e c rctiontion o syreneehyenzene mtrths notion s most se in t retion o Chter . he t

sed s sis or Chter 3 ere thered der e irection o

Proessor iche ode o .I. T his cooertion n min this inotion e is rety recited. Seer oer techin ssist

nts nd sdents t I. T contrited sstntiy to the deeoment ocomter rors or Chters , nd 7 this resect seci

ths re de to Roer L. Bmer, Brce Crocer eino R. Rodriez

nd Roert L Snde

che cottons or ths oo ere eroed t he I. TCottio Center. he thor rtey coees he innci so

o reserch nititio rt rom the Rohm d Hs Comy hich s

instment in the rertion o is tet

he or shes to eress his s to essrs Geores F Doriot,Henry W od, Wim H Coneton, John A Sne, d is roy

E Roe o Americn Reserch nd Deeoment Coortion heir idcedr e st or yers in rios sects o inci ysis d siness

jdment contrited ssttiy to the resent or

he retest sorce o encorement d ssistce n the rertiono is mscrit hs come rom the hors ie Betsy ihot her mny

ery thoht d si contritions, this o cod not he een com

eted

S W Bodm

Crde sschsetts

rch, 198


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Contets

Preface i

ntrodction

2 Reacor Dsi tiatio ad Cotro te Prodcion

of onocorobnze 18

3. Process rovemn or LiuidLid Eraction of FnayAc

4 Caatic Ractor Desi or Bne ydrognation 75

Evauation of e tods or Sfr rsoation 00

. Vac Fractionator Dsi for t Priication of yrnMonomer 125

7. Procss Desi and Evaation for e Prodction of Styrene

Monoer

end 99

ndex 229


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Inoducion

The nsa pacice o chemica engneeing esign eqies heappicaion o many aens an skis By he einiion o his poesson he pocess esign enginee in he chemica insy mple-mens he wok o he chemis an eveopmen enginee n poviingmechanica an suca speciaiss wih a ealsic escipon ohe eqe eqipen Shewoo has eceny escbe heolowing ncions whic ms be peome o span he gap beweenenchscale cemisy an he opeaing plan:

Rconiion o an economc oppouniy2 Concepion o a pan o esign3 Peimnay anaysis o he esin4. Compleion o in esign mplemenaion o onsucion an opeaion

ese ncions ae useu nicaos o he sages hogh whcha esign ms pass an o he vaios scales o hkng whch ae eqie o he eign enginee. he oegoing is is qie elp in

pacing each inviua ob n he pespecive o he oea eowc s eqie

he anaysis o esign poec s o be e-

membee a an economc valaon fo he enie po ec ms becomlee ae each sep in he esign; n he absence o avoableevaaion ae each sephe me an eo eqie by he nexsep canno be siie

o compee he anson om aboaoy ncepin o opeaingpan sccessully he esign enginee in insy mus ca pon awie backgon no ony o echnica unamnas b also o nan-cia an socia unesaning F example nowege o geogapha acos may be mpoan n seecing pope pan sie whiea gasp o copoae nance an economcs my be a peeqisie o

a pope evaaon an pesenaon o he economic benefis o begaine fom specic chemica poe. Cely an unsaning ohe opeaon o moen compuaion eqipmen s now an esseniapa o he aining o a esign speciais n aiion o avng a


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Cape

boa ecnical backgou e successul esign engiee mus connually evelop ales in analyng is own echnicl peomcean in evluain e efos n conbuios o oe people

The pesen ex escibes e ype o ecncl n economicbackgoun necessay fo he successul comleion of a cemcalpocess esgn hese fumenls will be summae biefly ine pese chpe Ts noucon s followe by a sees of e-sign cse sues a seve o illusae imoa aspecs o inusal chemcl engneeing esign

Te cses selece fo pesenion illuse o only eeypes of egineeg poecs bu lso iions in e eque egee of completo fo a esign ses eqiig cemcal eacoesgn seaion equpmen esig an ppelie sing opim-aon ae iclue Oe o e mos icul aspecs o ese esg

caseso fo mae of any ealsic eccl poblemis o efig e eal naue of he poblem eeciing wa is equie Oe o e moe common failigs o a ecncal pogam e-suls fom eecy o nswe quesion ha hs o been aske oo comple wok as o acully been equese Tis iculys pacully pevle in esn wok wee many iee ypesan egees o eo my be equie Te cse sues ee esee illusae iusil poblems a ae summe n he fomo memona In some insances e wee obaie fom elieaue while oe cases epsen acual nusial poblems

wee e aa ogne in a compny laboaoy an hee e incae esul consues e acual soluion pesee o maageme

In ec o hee cases ce he esg aalysis is sumae ine om of a compue pogam c is epouce i he ex Re-suls geeae by each pogm ae emloye o evlue he economcs of a esgn as ucon o e imoa pocess vaiblesHoeveesuls o all possble combons of ese vbles hveo bee obainea e compue pogams e pesee n oeh ey my be fue eloie o eine he economc evluoof e poecs o wic hey pply Tese pogams ve been foupiculaly usefu wen applie n a compue clssoom siuion wic class can commuicae ecly ih gi compuaionequpme

Te use o a compue o evalue in eal a cemicl pocessepeses oe exeme of e suaios h mg be encouneeby a ypcal nusal esign oup A e ohe exeme is esuion ee no ae esg o ecoomc elo s en oly moes numbe of calculos is eee o esablish hemos lely coiguaion o e lime esg I e cases o elae ye ic ae pesene i is volume a consieaion o lim

ing cses a e se o socu meos n pepaing he calculaospove o be mos helpu

y peseg a seies o cases havg no oly a ie ecnclcoe bu also a vaie egee o equie soiscions exaemps o llusae some of e conceps associe wh e suc


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cessu completon o an nstia pocess esi y eintonpocess esign s nvolve ith the application o technica pncpleso h availabe expementa inomton n oe to poce a ok

able mnactuing pocess As such esign cases have aitonaybeen examne inivaly th elatively ittle emphasis on a conss-tent set o pncpes ncessay o the pope nestaning ansuccessu execution o enea casses o poblems To some egeesuch a set o pinples can be estabise; as a e n mng theensuing case stuies meannu beyon thei on paticla bonaies the folon set o pincipes may be consee

etemination o esgn eqiements

2 Compehenson o maket contions

3 vaaton o expementa ata

stablhnt o citical es aetessatoan optimition

. vauato of pocess economics

6 Pesentatio o esgn esuts

The pesent intouction oes not ppot to be a thooh eve

o each bect iste Ony a cusoy iscussion of each pot s o-fee oethe th a eve o a fe petnent eeences Neitheshoul the eeence citatons mentione be consee as a completeliteate ve; they ae meely those that have pove se inokng th youn chemica ennees enconein te ist inustia esn poblems

DEEO O DESIG EQES

The sophistication o a pocess esn mst be tiloe to meet the

equements o the inivua sitution As mentone beoe the useo atapocessin equpment alos he esne moe eeom thaneve beoe to nvestigte vaous comntos o system paametes.nee one o the mao nctions o the peset text s to monstate the utilty o machne comptaons in styin vaious aspectso a pocess esgn Nevetheless the avent o oen comtesmkes it qite easy o the use to pass thoh the point o mnshng etuns. A eat ea o obectve thin s eqie to avosoving poblems meey o the intelectu satsacton gaine omhe sotion. As in al aspects o enineein o sty te vaeo the pogamming an compute time se is not exceee by thevaue o the esign impovemnt aine then both engneeing ancomte tme have been msspent

To etemine te possible nee o etale esn cactiont is most se to nalye imitin aspects o a esi situaton bymeans o mple han calculations Compttons o imitn cases


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1

are often qute strahtforward snce smlfying assumtons cansualy be mde For emle, f a aboratory reactor as been operated adabtcay between to temerature leves, the resuts of schan exerment can be scaled drectly to a comercilscae adiabatc

nt oeratn beteen the sme two temerature eves. Comarson of ths result ith that obtained by assng an sotherma oeraton at the oer temeratue lee sets the extremes beteen whchnonsothera desns must fal By notn the variatons n the m

portant desgn paameters as the desin is shfted from one lmt toother, one can assess the need for min more detaled and oftenmore tmeconsmng caculatons at ntermedate conditions Suc acacton rocedure s iustated by Chater n hch reactorfor the hydoenaton of benzene s desgned. The need to ake coaison of imtn conditons wold seem obvos nevertheess,

ts sme technique s often overooked, resun n an nnecessaryeendture of enineerng and/or comuter tmeOne of the most vauabe talents that can be develoed by the de-

sgn enneer s an abity to erfor the me calcuatons necessary to esablsh the lmn cases of design, where the most df-fcult technque s often hat of mkng the approate assumtonsn order to sify the caclations Ths ablty usually ust bedeveloped throuh my years of eerence, and the noce oftenfnds t qte dfcult to achieve It s to be aprecated, oweer,that the abity to perform a smle but meanngful analyss of a prob-em does not deveo atoaticay wth exerence conscos ef-fort mst be made to comare the results evdenced n the fna oerating plant h the assumtons made n the early stages of the degn.Only by such a feedbck and by comparson can the quaty of subsequent estimates be ugraded

The need for ltngcase calculaons cannot be overemaszed;such calculatons shold be applied as eary as ossble n the conderaton of any chemcal project. Moe nd moe effort s bengmade tody and w be made n the future to provde the researcanaer wth a qanttative estiate of te oabity fo he tecncal and economc success of a artcular research project. Clearly

a major ingedent n such an estmate must be a relmnary forecast f the capia and operatn costs for the poject. Ths tye ofestmate s necessarly based on lttle or no data, and te omuta-ons must rest from se sort of mtngcase anayss Thus theablty to erform suc an anayss s vauabe not only estblshng

prelmnary lmits on the process vrables but also dtermninghether the probablty for financia sccess stifes te exensesnvolved n the benchscale and potscale expermenta work

In ths ght, the degn enneer shoud enter nto consderton ofa chemca proect t the bnch sage. his ntia caclatons donot show a hgh probabty for fnanca sccess, the very exstenceof the bench wok shold probably be reconsdered ness exernarcmtances, suc as a rawmatera postion, are more mortanthan cnoc actos Smlarly, as wrk proceeds throug benchand piotscae deveoment, dscussions between deveoment gropsand ocess desn engneer my be very mortant, partclarly n


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coontn ecnc poess t e effos of ke eseacoups

CPREHES F KT COO

Cooeaton between te des enee n e ake eseacan deveoment ous s of cca motnce One of the mosessenta peces of noon eque fo te cometon of pocess esn cacuatons s n estmte of bot pesen a futuemke eands fo te pouc ne consdeton n an caseshe bt of desn ennee o nze technca nfomton ndo ovde n accuate sceu o commeca equen aveon modes nuence on e economcs of te fna oean pn

O e othe d n ccute ses foecst fo oduc s usuque ctc to a eastc pecton of te ume fnnca efomce of the oetn unt

Fo exame, 20 pecent eo n knetc constn o eat-nsfe coeffcent m be ame out a that ste n he cacuons n hc te ovea pocess econocs e consee. Hoeve, sma pecente eo n ke foecs e bemfe s t s tnse tou the cacuatons eadn o neconomc evauon of te oject.

Soces of mke nomaon un the a fo ovenmenteots to te annu evews ubshe b te vaous e jounasMos motan, oweve, e he esona scssons of sesment customes, nd s hs te of nteacton hc fos he bestbass fo ses foecasts Tpc te ses foecsts be e

pae n te ve ea stes of ocess eveoment bu e aesubjec to a n substant devatons as te mke esecok poceeds t s essenta tt the pocess desn ou be con-tnua ket omed on the sttus of the mke estmes n nts can fna es be oduced hc w be ustfe besen and fuue ke esttes Fna t shou be emembe-e ht nt constcton s usua fnshed wo es o moe te

the des pns ae cometed. f economc condtons e favobete nee ofen ses o exand the nt factes even befoe con-stucton s comee s facto fute emhszes te nee foaccue ke foecstn poceues

Becuse of te ffcut ten nd ocessn nnfua , te cec enneen tetue as stoc venon scant attenton o te subject of aken. Moe ecen, evbt of e eectonc comute s de feasbe the coecon n assessmnt of ke nfomton suffcent boad nd c-cue o ao the eveomen of usefu mken teoes s

ped to he chemca ndust A coesondn ncease n esec

nd ubon cvt n ts aea as been evdence Of patcunote s a sees of aes pesente t a 965 Aecn nste ofChemca Ennees smosu n hch te ntecon of esec,mketn, n esn effots as scusse (,11,3,, ese

es ee ee b men m th a asects of oduc


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6 tr 1

commercalzon n he chemcal ndusry, and he seres provdesan excellent exoson of he advanaes o be aned nd he problems encounered by efforts o coordnae marken and research

prorams The aers are parcularly valable n llustrang hevarous mehods by whch n ennee can assure ht n deqaerket pcure wll be obtaned and tha crrespondnly ccraefnacal evaluon wll be acheved. Another comendum of paersdealn wh chemcl marken has been publshed by he AmercnChemcal Socey Ths book, whch conns weny conrbuons,serves as an excellen backround source for he seclzed areasof mrken For exple, the roles of roduc dversn, alcaons reserch, nd produc delvery mehods re ven dealed rea-ment

There s a very defne need for a complete revew of recen

chemcal markeng leraure Such a revew, preferbly carred ouby soeone wh a sron backrond of ndsra rketn eerence, wod no oy cry e so or te stden bt woldlso hoeully lead to beer mrket nlyss echnqes for he ndusry as a whole.

VAUA F XEMA T

he manufacure of a parculr chemcal, the requred processseps enerally follow he sequence shown below:

reparaton of reacns2 arryng out of reacons3 Heatng or coolng of reacton prodcs4 Separaon of reacans fro producs and purcaon of

producs

Almost wihou exceon, he desn enneer s requred o bsehs analyss of each se upon lboraory d enerated by other n-vesaors or obaned from he lerure For hose havn only amodes eosre o he chemcal lerure, Mellon (3 has provded

a very useful ude o he proer mehods to be used n searchng helterature. In usn lieraure d for he enneern nalyss of aprocess oeraon, s crtcl o develo n arecon for theay f he nformon o be used. For examle dta reoredmy years ao may hve been obtaned bfore sffcen heor habeen develoed to allow roer nalyss nd resenaon of the ex-ermental nformaon In he bsence of sch a theory, early expermeners somemes faled o mesure varble necessry forproper anlyss. Obvously, he eermental equpment avlble nhe erly enneern laboraores ws not as sohstced s hacurrenly avlable s herefor motan o develo an arec-on for the strenhs nd falns of varous types of lboratory a

prusDfctes wh he proer nterreon of ublshed d re

frequenly comounded by ndusrl censorsh of procss nformon. he suresson of techncal nformon s obvously necessry


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to poect the commci vue of a pocess Hoeve, fom tecnica viepoint, censoship often requies the ennee to mke aresonabe ssumpion in oder to be be to poceed ith hisnysis

A ood exame of the censoship of isti nfomtion is povde by acin 0 ho dscusses the dsibion of eaction

poducts fo the choination of benzene He pesents data that estbish the distribution of the vous chonted componds as fnction of the tota amount of choine ected This infomion is ofcose not sfficient fo the desin nd evaaon of a mnufactinpocess since the kinetic paameters fo the ections are not dis-cosed In ode to copete esi easobe ves of he chemica kineic constnts mst be ssumed; sch pocedre s fooed in pep Chapter 2 in hich vios pocesses fo the choin-

tion of benzene e discussed hen it is necessay to poceed ithis manner it is most desirabe to obain iteate informaion foms many dffeent souces as possbe By comping and combni vbe infomation oe is oten moe ikey o estbish a eistic basis fo a design fact the technique of gahen nd comparin infomion fom numbe of souces is fequenty usefu nmany aspecs of a pocess desin

efoe nvestin the time and effot eqied even by a peimin-y desin ccution, it is pdet to ssess the vdy and con-sistency of the aoaoy findns upon hich he desgn is to bebsed. This ssessment is ost esiy ccompished by compinthe data diecty ith ppopite iteaue ifomion For exmpethe ene ccuacy of a set of vpoiqid eqiibim dta fo amixtue of to comonents my be checke mst diecty by com

pin them ih those fo the same to comonds but or other conditions of temetue and pessue sch dta ae not vibefo the desie componds te etive votiity computed fom theboatoy esut mht be comped ith ht cacuted fo an idemixtue by usi out's It my aso be ifomtive to comethe retive votiity ih that fo oher compounds havin marchemca suctues Finy the themdynmc consistency of he

data shoud e assesse by invoki one fom of he GibbsDhemequtionSimiay, by pottin the obseved soubiiy of soid in a iqui

vesus the ecipoc of absoute teperatue on semo paper oneshoud obtain a stigh ne fom hose sope the heat of soutioncan be comptd A compaison of is het of sotion ih heats ofsoution or heats of fusion for chemcay simir compounds yiedsa check on the vdity of the expeimnta data An naogos techniqe apped to chemic kietic da o chemc eqiibim dtoud yied an ctivation enegy o cemic enhapy chane thtcoud then be comed i iteatue vues

be - s been eed to smme te etods o assess te dty se tyes dta most te coeed in com

peting desn poects fo the chemica poess idsties. It is tobe emphasized t this tbe is not a summry of desn methodsbt meey a set of citeia by hich to ude the qaity of technic


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8 1

data t be sed n cayng t a desgn The efeences shn aent ant t be cmehensve meve t s clea tha he tablevasly vesmlfes the types f peatns caed t n hechemcal nsty as well as the heetcal and techncal backndnecessay f he cmpletn f even a sme desg pblemheless the nfmatn smmzed has ved ey useful napplyng he esults f theetcal cnsdeans t engneeng pblems f pactcal sgnfcance Nataly n mny nstances t sbth desable and necessay t splement the elementay methdsdescbed n Table 11 by sng sme f the me advanced the e tcal deelpments

The utly f he nfmtn smed n Tabe 11 ntallyvaes sgnfcantly fm ne segment f the chemcal pcess n-dsv t anthe. examle the anc chemcal ndsty mkes

geat use f extactn and leachng pcesses, and the smple tech-nque f plttng slblty data n semlg ape t btan a heat fsltn can pve t be f gea and feqent ly. Once cnfdencen the eemental data s develped, the desgn calclatns t ptme he nmbe f extactn leachng sages can pceed qutesmhly.

en heetcal celan f pcess mtn s mpssble,he use f a facally desgned eemenal technqe may be fgea vale. The use f satstcally desgned exements s aclaly alable n edcng he eqed amnt f eementaland anaycal eft t slve a pblem f hch thee s ltle ntheecal bass. The fllng eeences aanged by Kehle,pde an excellent ntdctn he applcatn f statstcal cn-cets t a vaey f pblems encneed n the chemcal ndsty.esdes a dscssn f statstcal desns n the analyss f labaty and plt plant ta 7 the sees als efecvely pesentshe advantages be ganed by the applcatn f statscal echnqes nplan eemenan 22) t the se f cmtes n data educn (41), t the selectn f appate pdctnlne cntlchats (1 and t the geneal mpvemen f qaltycntlmethds 2) hen a snd theecal bass f a cess desgn s

lmted, the se f satstcal mehds can pvde a hghly seflfndatn f the necessay desgn and evaatn calclatnsOne last pn feqently velked s the need f peang an

adeqate e analys. f the pbable e as cmted f theexemental echnqe used s apxmately eqal the andmdevan f the data abt a celang lne, then t can be assmedwh a hgh degee f cnfdence hat ll sces f e have been

ppely esabshed and accned f Sch an anals lends ageat deal f cnfdence t the se f the dta n a desn, atculalyhen he eendte f a lage catal nvesment s eqed.

ESBSET HE DEG PEE-SU PZ

In hs ext, Shed states qte appately that the desgne mst be llng t me assmns. Once sffcen nfma


15/236

Tble1-1.UefulMth

fEvutigdCrtngChmicEnnrg

ExrmentDt

ProcesOeratio

RqiredDesgPraeter

Fdtrasportato

Frictiofactor

Fdhetigorcoog

Ht-trnsfrcoeffict

hecareacton

heca-ktccontat

hecaeirmcott

aaycca

etivnesfctor

ro

Msstrarcoefcietfrom

fidtocataystpeetsrace

Srryreaction

Mas-tsercoefcetro

iqdocataystpeetsrface

Srgedreto

Msstasrcoeficita

tthe

kqdsre

Mstrasercofcetfro

agetokd

borto

Sotofgaiaiqd

Bogor

Vaorprre

costo

Dstaon

Vor-qdqr

rteoty

rayffcc

Crsazato

Soirsoiity

xro

Dstronro

ot

BaeforEvaation

or

CorreaionofData

1/2

N

j/

FHe

Arrheicorreation

an'tHofcorreaio

Theemod

jo

Fl

kL

pAp

kL

(D,

a=

(D,N,Vs)

Heraworotaw

CaCapeyrone

qatio

GbDhemeatio

Mrphreeeffcicreatiohp

Cpeyron-tpecorre

aton

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eerece

3-

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-c


16/236

0

ton s avalable to analyze a process completely and accuratey,typcally the fnancal ncentve for completng the desgn l be substantally dmnshed. However, order to me approprate pre-mnary assumptons, the desgner must develop the capablt ofsolatng te varables that are crtcal to the determnaton of theoverall economc performance of te process. Freently a prelmnary desgn caclton s rered to establsh the dentty ofthe most mportant desgn varables. Suc a case s llustrated nChapter n whch the hydrogenaton of benzene s consdered.

For the more common process operatons, the crtca varablefreqently s ell known eg, n the desgn of a dstlaton coum,the reflux rato usually serves as a mst senstve ndex of the pro-cess economcs. the frst analyss of a nque or a hghy complexdesgn, the determnaton of the most crtcal varables often s left

to the jdgment of the engneer. ypcally hen a multvarable desgn s approached, a base case s selected by arbtrarly establsh-ng reasonable" values for mny of the process varables that arebeeved to be east crtcal n determnng the process eonomcs.he varables thought to be most crtcal are allowed to vary, and a

prelmnary economc evalaton and optmzaton of the desgn arecompleted. hen varatons from the base case are consdered byaong varatons n the parameters that had prevously been fxedAs sho n Chapter n hch the economcs of styrene productons consdered, the use of a dgta computer can greatly facltate theevaluaton of the base case and the varatons from ths case that aresnfcant. As llustrated n the same chapter t s essenta to re-turn to the ognal set of assumptons n order to establsh the efectof each assumpton on the overall economcs of the process It salso mportant to realze that n dealng th a mlt varable desgn

problem, several local mnm may exst a certan amount of judg-ment must be exercsed n determnng whether a ocal or an over-all mnmm as been acheved.

The calculaton procedure descrbed sffers from the lack of anorganzed approach to the problem, and a great mny decsons mustbe reserved for the judgnt of the engneer. In certan types of de-

sgn problems, a more qantttve approach to the logc requred fora desgn calculaton my be acheved by applyng the technue oflnear programmng. hs mthod hs applcaton n dsgn casesthat result n lnear algebrac relatonshps. Happels very useful texton chemcal process eonomcs 18) ncludes a bre descrpton andan example of lnear programmng technques. It s mortant to notethat mny chemca economcs problems are hghl nonlnear and thatn such nstances lnear programmng technues are not drectlyapplcable. However, by lnearzng the approprate analytcal expres-sons, lnear programmng technues my be helpfl n establshngthe general nature and relatve mportnce of the cost functons nderstudy

A sgnfcant porton of modern chemcal engneerng researchhas focused on the development of advanced methods for processoptmzaton as appled to ndvdual sectons of a process as well asto the overall desgn result. Partcular emhass has been placed


17/236

on he otimition of chemical eacto systems uch of his wok iswell summaied by Ais (, 6 Denbih and Kames andWestete 2) ne of he moe imotant of moden otimiationechniques is ht of dynamic oammin, whic the last of aseies of staed oeations is s otized the last two staes aethen otimized as a sinle unit One stae is added on in a stewisefasion, okin backwad until the otimum condtions fo he entie

ocess ae established This ethod has obvious alication in thealysis of continuous stiedtank eacto systems ( The cal-culus of vaiations as been shown o have aticul vlue in the oimiaion of ubul eacos he metod is esecialy ueful in hecase of adibatic eactons In addton to te afoementoned temehod of steees ascent has also oved useful e oimizaionof eacto systems ( Tis echnique allows one to aoac an

otimum as closely as desied by successive quantum chanes in theocess vaiables until the desin aamete n question (e yieldis otimied

Concuent with the develoment of otimization methods hs beenthe establishment of new techniques to simlify nd minimie desincomutational efo osen 38) has esented a achine comutaion method fo efomin ocess mateial balances, nd viczand oan 6 have eoted moe flexible om incooan both hea and mteia balnces Saent and Westebe 9have develoed a nealuose aoch tht is vey elful inoaniin he oamin wok equied fo the comute simula-

tion of a cheical ocess.Moe ecently ee Chisensen, and udd ave made vey

sinificant contibution in he study of multiiable desin oblemswhee assumtions ae equied o oceed wit the desin Theseinvestiatos have estblished a method hat allows he essinmen of values to a seleced se of desin vaiables in such way asto minimize he comutationa effo This wok is one of the fistsins of a tend in the chemical enineein ofession to mke oeeffective use of comutes in the analysis of ocess desin olems.

EVALUO O PROESS COOCS

hen te chemis undeakes fundamental eseach oecin he aboatoy, he fequently s only a limited notion of he ulti-e alications and ossible financial success of is oduc. Thisso of fedom has oved invaluable in develoin a ceaive amoshee fo the develoment of new oducts. Howeve, once a chemicaloec emees into alied eseac o develoment, each subsequentse in e oect should be elted finanilly befoe te wok fot stae s undetaken In his anne oecs hvin a ow obability fo an accetable fincial eun cn be " weeded ou" t anealy stae, and oe tecnicl effot can be alied to deveonhose oducts whic e ost likely to ealie the etes eonomiceun

One of the citica ftions of te desin eninee o any otheeson esonsible fo evaluain the ocess economics is o ke


18/236

12 Chapter 1

breast of the latest tecnical developments in new prodct nd tonterpret hese developments the lgt of ther ultmate efect onte rot otential or eae if t odtion yield of nw

prodct s ncreased by crryng ot e reacton sep prtlarsolvent, the cot for separang he prodct from the solvet mt beestmted t may be tht he cost of recoverng he product over-shadows the saving generted by the ue of the solvent sch the cse, he corse of he erly poce research and developmentfor he prodct ll have o be ltered acodingly

The actal form of inancial evalaton varies dely ithi tendtry; and becse of he ovos comercal ignfcance of evalaton tecniqe, ltle menngfl nformaton s vlable thelterture However, some generl eferences re valable wichhve proved very efl n orienng chemts nd engneers to the

problems ssocated th a fnancal evaltion frs pprochng an economc evlaton, one of the mjor df-ficles encontered by he technally rned person s tht ofnderstandng financal termnology he wor of Bete and Vvn grealy mitgaes ths problem; t provdes dealed compatonof the defintons for most terms comon to finacal nalyss sappled n the chemcal ndstry dditon th e mporance of uingconsistent termnology s well llstraed

n ts smplest form, the finacl elaton of cemcl projecprovdes a estmate of the cpl reqred for the contructon of

the manufacturing fclty nd forecas of the costs reqred tooperte he propoed proces By dedctng the tol operatng cotsnd income aes from the ncpaed sales revene, h et oper-ng ncoe for he projet cn be estblshed ddition o he n-nal dolla nome volme, proftblity my lso be eresed the frcton of he capital vestment needed to etablh the antic

pated etur The philosopy iding the nlysis of corpore venture the chemicl indstry s well sred n an AChEpublicton 2).

Each compny has its ow pecular rawmaterial poston o protect, its on process nowhow, t own acconting system, and its

o plan for ftre ension As relt, the identical propoedproject my met different fates, depening upon the copany thatconiers it For example, conser an Aerican company hat idomesticlly sellng producs at are faing opetition from idenical prous manufactured urope. The European concern ightbe ccountng for the cost of ts goods on an increent basieabass n which deprecation nd ovehead cost re llocated entirelyto the doestic porion of proction while the procton deignedfor exort i brdened only wih diret epenes Clearly in suc asitaton he Eropean frm mght fnd tself in a very advntageoscomettive situation even fter the ransortation cost re tkennto acont Th a diference n cotacountng tehniqes cancuse vat dsparity in te comercial market place Similar examples are vlable here dfeence n rwmaterial poston andprocess knowow lead to subtantal coercial mplications


19/236

Introducio

Some o he moe snd mehos hih my be use in oun-ing o hemil poe oss e eluied by seveal exs ls ,) I should be noe h eh company has is on equieminimum eun on invesmen o poe o obvious esonshese iges e neessaily hel in oniene Hoeve, in he ab-sene o exenl cicumsanes ( eg, meil posiion) anesimae o 8 o 0 pe en s pobby ealisic loe limi on heeun on invese apial equie o poe apoval Muh higheeun eeges e obvously desibe ae eque obaine

The mahemis invove n evluaing he eonomis o a hemc po beomes quie nvolve hen he en values o hevaious sh os ino an ou o he poje e consiee In asignii cle, Soudes 7 has poue n exemplay isus-

sion o his issue ogehe ih n ineesing ompason o he e-es o vious poibily cieia on he uimae invesmen e-cison o he ede ineesed in a moe oplee bkgoun he umenals o engineeing eoois his pe o ines sho b useul bibliogphy o einiive oks in hs ield

ne o he ge iiulies in povidin n aue inanial eval-uaion ies n he a ha boh he make pie n he demand oiniviual pous s ell as he genel developmen o he naionleoomy e ynami unions The innal peomne o planshoud be examine s uncion o oh shoem highquenyvaiions and o logem, gu goh o deline n he ovolume o pou sles Shek ( pesens bie disussion nd useu exmpe o suh suy He pOins ou h he eonois o chemil poje e mos songly eed by viaions n heseing pie olloing e he seling pice, nd in oe o mpone viions n he sles voume, sales eenses, an pialinvesmen hve ben ound he mos ciic aos eing he eun on invesmen The need o eque pie n sles oeasingis el iuse b his isussion An exmiion o h iuneo viaos in sellig pie, somemes cle isk naysis, isequenly equied componen i he inl pesenion o he inn

ial evluion o ne hemil poeale and Maloy 9 povie useul iscussion o he eeso lonem emnd selling pie, an capiy viions on heeconom eun o be niipaed o given hemil poeVaous mehos o gphially illusang he eonomi peomaneo a pan e ell illused i his eeene piua, i iseeivey demonsaed h ouning o ime viios n emndn pie hs mi ee on he opimum pn size n myiay inluene he deision hehe he pan shoul be buil al

A mo deeen o he pope inanial evauaion o peliminyesigns aises om he puiy o elibe apilos inomono poess equipmen Chilons exelen complaion ( povies useul bkgound o he pobems o os esiming d o he

pope mehos o os da coelaion The coeions coninedin his ex e quie equae o peping pelimiay os esi


20/236

Cape

mte owever it i recomended tt oter orce - be con-lted in order to veriy cot etimte In prticlr te priceetimte for te lrger pice of eqipment old be cecked bying two or tree diferent reference. e te dig rece itfinl tge it i norml prctice to coct pplier in order toverify te eimte for ll ignificnt piece of eqipent

PRESENATION DESG ESULTS

erdle of e qlity of e tecicl work t contribtedto te dein nd evltion of cemicl proect te totl eort mybe vlele nle it i properly preened o toe wo mt mkete limte invetment decion priclr te need for lcid

tecnicl wriig long been reconized n iportn ie ndeverl ecellen tet re vilble for i prpoe 4Generll lck of qlity in tecnicl report c b trce to lc of effort in prepring nd poliing te report rter tn to lck of knowlede of grmmr tle or proper report orgniztion.

fte te relt of tecicl efort t be preeed orllyFor te peker wo mt mrize m of tecnicl inform-tion in or time te Americn Intite of Cemicl Egineer

prepred n ecellent boolet wic mrize te imporntpoint o remember in preprin te preetion It i priclrlyvlble in pOiig ot te mo effecive mod of in lide

n oter vil id T et of Atwood 8 Flec () nd ever(51) erve vlble referece o e more generl pect of prepri d eecing orl preenttio.

SUMY

Te foreoi ecion provi brief introdcion to o of emore ipornt ie tt confront te indtril deign eneeri e prcice of i profeion Soe of e pOin diced g-get vro tp of forml trinig necery to te ccefl

eectio of deign work er e et pecific pproceto deign problem wic ve been ond efl I prticlr tepproprie ppliction of electronic comption eqipment to id inte dein clcltion reqire more n ever before e e ofengeerin tlent o copreend nd nlyze te copted rel.Te followi cpter provide erie of deign ce tdie werein t iport pect of indtril dein prctice re brot tober on reliic problem itio vin comercil igificnce

OO

a Interfcil rfce re

D Diffion coeffcent

D Ctlyt peet dimeter


21/236

f icon co

D Massanse aco

jJHeaanser acor

IlL Liqudpae massnse coecie

N Roaona speed o ipeler

Re Reynods number

Vs Seici as velocy

Dynamc viscos

p Desy deence eeen soid and qid

R

ntrouctio 15

1 Amecan Chemical Socie Cemc Makei n he Coeiive Sxs Advnces in Cheiy Seies No 24, WshionDC 5

2. Ameicn Insiue o Chemcal Eniees Venue Analsis

AICE Pbcaon DepamenNe York963 Amecan Inse o Cemca Eiees Gde o Wies d

Seake AICE Pubicaion Dpen Ne ok (1964 Aies R S nd R D eon Cemica Enineerin Cos si-

maioncGaHil Boo Co Inc,Ne Yo (1955). Aris R The ima Dsn o Cemica Reacos Academc

Pess Ne ok 161)6 As RIdcn o e Anlyis o Chemia Reaco

Pcea IncEneo Cs NJ 965.

7 Ainson A Ce n 73 o. 0 4 (66)

8 Aood R L Wn Yu a Aood CopoonMelseMass (159)

Bare,M,Chem.EngP,No1026 9650 Beae R D an J . Vvian Ce n N (13 re

pined n eeence 12 p

11 Baey J WCe. En. Po No 01 165)

12 CionC H. Cos ineein in Pocess ndusiMcaHi Boo CompanyIncNe Yo (19).

13 aveJ K Ce n Por. No 0 24 (65)

1 Denb K. G Te Prncipes o Chemica quiibrium ambde ve ambrde 96)


22/236

h

15 Dnbgh K. G. Cmca Ractor hory Cambrg UnvrsyPr Cambr U5

16. Flesh R. e At of Plin Talk, Hrpe Boher Inc., Nw

or (1946)1 7. Frun, A. Ch Eng 73 No3, 70 (196

1 8 Hppel J., Chmica Procs Economis, John Wiley& Sons, IncN ork (1958)

19 aot P.AI.Ch.E.J. 93 962.

20 Horn, F, U roltnr Ch ng.c. 3382 (1960.

21. Hougn, O. A. K.A. Watson an . A Rgtz, Cmical ProcssPrns, Part I, John Wl & Sons, Inc Nw ork 1954

22 Huntr, J SCh Eng. 73 No. 7 111 (1966).

23 Htr W. a A. C tknson, CEng 3 No1259 (1966 Knnl W. E. Ch. En. Pror No1020 (1965).

5 Ko K.A Cemil Enneering Reports: How to Search theLiterature and Preare a Reort, Inter science Pblishers, Inc.New York 957.

26. Kohlr L C. Eng 3 No1, 81 (1966)

2 7. Konk A. A. an C J Kng AI.Ch.E.J 9 196)28 Krmr, H n K . Wtrp Elmns o Chmicl or

Dsgn an rton Amc s Nw Yo 9329 , W J H. Christnsn n D. F. u AIChE.J, 1104

(1966.

30 MMuln, R B h. En Por. No 3 83 (1948

31. McAms W H, Ht ranmsson MGawHl Book Compny,Inc. Nw or (195

32. lon M G Sarchng th Cmcl Liraur, AmrcnChmica Socty Publctons, Wahngton, D.C 1964.

33 Nlon, J. R Wrtng th chnca Rpot McGawll BookCompany nc. w York 197

34 Prr J. Cm Ennrs' Hanbook, McGawHl BookComny In Nw o 1950.

35 Ptrs M S, Pnt Dg an conomcs or Chmil Enn-rs, MGrawHl Book Co c, Nw ok 958.

36 avcz A n R. Normn Ch Eng. Progr. 60, No5, 71

(1964)37. obinson C S. an E .GiliaElmets o Fracona Ds

iaoncrawi ook Copny Inc w ok

38. Rosn, E M. Ch Eng. Progr. , o 1069 (1962


23/236

Itoction

39 SargtR W. H., A W WstrrgTrans. Ist Cm Eg 90 (964

40 SatrlC an T K. Shrwoo Th Ro o Duson n

aalss AsoWsl Pulshn Co nc.

Ra ass63)41. SavtzkyACm. En 73 o599 966.

4 Schnk G.Cm Eng Pror. No 1016 (965

43. Scwr H E Procss Egnrng Economcs McGrawHlBook Company Ic Nw York 55)

44 ShrwooT KA Cors Procss Dsgn T IT PrssCamr ass963.

45 SmanSO Horass an J W Flton In Eng Cm 32(966

46 SmhJ Chmca Engnrng Kntcs cGrawHll BookCompany Inc.w York 1956)

4 7. Sours Cm Eng. Pror No3 79 (1966

48 SouhrJ W.cca port WrngJoh Wly & Sons Ic.w York (195).

49 walJ Jan J. B MalloyCm Eng. Progr No 790(1966

50 lra F Can C. Drn hmcal Engnrng PlantDsn cGrawHl Book Copa c.w York 95).

51 Wavr R Th Ehcs o Rhorc Hnry Rnr CoChcago Ill ()

52 Wr H C an H P ssnrThrmoamcs or ChmcalEnnrsJohn Wly & Sons Ic w York 5)


24/236

2. Reactor Design, Optimization, adConrol n the Pouctin ofMonochlrobenzene

This s as 'it desgn o rocss for th hoiatol obeee i ljJws s pced o t jroj)r oreton ooto dta tht th t o t thee qutcoaiol ectons Se )o schll ld oh btca Ol1tl1OU oj)tios xal1 ojtlle ono-

mc, Th ost tt' )oess s sect b }l o el1 t est s o t f tiol, la the th aby o O/tlII j"oss s inestt al h el s ofepjro/)t oe to s oao

T c/)t j)roLs oppot o t vetoH ld aaiof riOs pocss scms, 'a atatie dsigs r abec t off dlg o'e o cs Old nt rl text Ts aYt's qu j)ro/) coud forll basi for en ad ololc ols T ectso is c/) zs O te iol o th ppro/)t deg

jalle sc h t colo o o t)e o to igsl b cOlljad mlf 'y,

j Phcec op

eccus ew Jese

To J A. Sh, eerFo W Ae, Mer o Techic eros

x s oe houh o mig is o moochorobezee i-sed o urchsg hs iermedie ro he ousde Sic e hehorA roducio is o shu do here re hree recorsh migh be mde vibe or cor bezee ou re r e

8


25/236

co D OjJ d Crol 9

quese evue he esby hs rje uner he ssum-n h bh benzene n hrne wu hve be purhse

The hree rers re equie wih s r heing n g

n ih gs isribrs ssure h he chrie s we ispeses s kee he qui sure wh hrine The rer s reneessriy pe re amsheri res sure h hs reuxnenser hrne gs reyce sysem n r, n 550 q ing sure n he rm ube hi i O 5in ubing Wh h e gr n ern, ver he rnser ce-cens 150 Bu/hr) sq ) F) he been bne r benzene 60 wi ing er n e Drn ern, rnebein e ech rer w h 40 0 ns iqu Aeque sn iy s vbe sere he unnvere benzene anhe hrine rucs ehngre mnhrbenzene n a

mure n rhrbenzenes is nie h his ermure cnn be s n h i hve be sreThe kines he iquihse hrnin benzene hve been

nvesge by he Res erh Dermen her resus nrm heerure rers h he hrnin benzene mnhrbenzenen hrbenzene s n cs es irs rer n rever sbe bsen rte equns n hch me rns nse mes er unvume) re emye The brry es s ere ar re u n a 2er sk eque h reu nenser h reurne everyhngbu exess hrine Te qu s e gie by he bubbnghrine hh s e hrugh re ss bubber Sm muns errc hre were use as a ays

The re sus he brry es s re summrze s s

Me FrnTime Me Frin Benzene horobnzn(hr) 40C C 0C 40C 5 70

0 0 0

0 3 06 3 5 0.6 0 4 9 0 9 0.66 0. 009 0 32 602 8 044 0.0 0.8 53 0 514 0 70

60 0 6 09 0 43 05

2 031 0 63 0 59

veny he rmin rhrbenzene s s sm h mybe neece

The ssiby usng he hree exsin rers r bhchrinns hs rey be en exmne n s eems er hsme rm cninuus erin wu be reerbe Yur suy


26/236

2 Chp 2

shold be restricted o continos oeration for a maxim of 7000hr s/ear The maxi oerating eeratre is 70C ; higher eerares lea o excessie aorization and srain he caaci ofhe conensers We need 8 million lbs of monochlorobenzene er ear;we hae no wa of selling addiional rodction a more than an n-accetable istress rice

The atched c os figr es are proxmate b shol be adeqatefor he roe of or analsi s Secificall, o are aske to ealae the oss ible financial retrn o be achieed b rocing monochlorobenzene adiion o ar e to sec if he otim manner inwhich the rocess shold be rn

Daa AmpioChecal coss an ne sales an se ales

ChlorineMonochlorobenzene b 132C)ichlrotrichlorobenzene mix

b 17208C)Benzene b 80C )

$0 0/lb$0 10/lb

negligible$0 03/lb

ecoer cots toal incldin both fxed and oeratin coss):

MonochlorobnzeneBenzene sg O 88)ichlororichlorobenzene mix

erang coss , each reacor

eacor heating an/r c oolingabor an serisionChlorne reccle

$0 01 0/lb$0 01/lbzero waste)

$2 0/hr$2 90/hr$ 00/hr

Total fxed charges on each r eacor, ncldng iing controls andaxiliaries $1 , OOO/ear

As an aroximation assme ha the molal ole of each of therocs i he sme as ha of bezee ad ha her s no olechange on mxing hese liqid s

a aa

rodc

Benzene liqid)

Monochlorobenzeneliqid)

Dichlorbenzeneliid)

Chlorn gs)

HC gas)

B{lb mole) M Formatn a 2C

3 3

3 6

3 8

8 1

6 9 6

1 1, 700 gcal/mole

2 00

900 aerage)

22 , 063


27/236

R eato Dsin, Otition and Control 2

gee Neare

Hearanser area aailable in each reacor, sq f

a Cos or b enzene cone re o MCB, ollars/ear

b Cos or benzene conere o DCB, ollars/ear

c Cos or chlorine conere o MCB, ollars/ear

Cos or chlorine conere o DCB, dollars/ear

Cos or separaing an reccling benzene, ollarsear

f Direc operaing coss or he hree reacos, dollars/ear

F Flow rae o a reacor, lb molesear

g Cos o recoer o MCB, dollars/ear

I Fixed charges on he hree reacorsdollars/ear

k 1 eacion rae consan or monochlorinaion reacion, hour1

k2 eacionrae consan for ichlorinaion reacion, hour1

KIn klV/F, with /l evaluaed at emperature Tn'dimensionless

K2n /2NRF, with '2 evaluaed a e mperature Tn' dimensonless

K 3 R/F, dimensionless

NR Moles in each reacor, lb moles

F Sensible hea absorbed b he cold entering benzene ee sreamB/r

q ae o hea ranser o he cooling waer in a reacor, B/hr

Q" Toal rae o hea generae by he cemical reacions in reacorn, Bhr

R eccle rae f benzene lb moles/hr

t Time hr

T Temperaure, oK

e Te mperaure o cooling wae r, C

Tn Temperaure of reacor n, C

TR Temperaure n a reacor, C

U Oerall hea ranser coeficien, B/r (sq ) F)

x A Mole racion of benzene in reacor n imensionless

On Mole racion o monochlorobenzene in reacor n, imensionless

xCn Mole racion of dichlorobenzene in r eacor n, dimensionless

tI Ehalpy o f chlorinaion reac ion, cal/ g m ol e o f chlor ine

t T-e,C

eraing ime, hr/ear


28/236

2 Chp

PREINY DESIGN AALYSIS

The rectos are to be oeated continosly it is therefore cear

that the flow rate t be emloyed wil b an imortant oertinaiabe The reacto rs may be oeted wih ser ie s fw throuh thethee o ed for two or a th ee in arallel ecycled benzene cane etuned to the first reactor o r distributed to al thre e Eachreacto may e erted at a dferent emerature

The reactor system wil be desied y first exminin seeradferent oce ss scheme s where each reactor i s erated at thesame seified emeratu nce the roer roces s fow attenhas been estlshed aitn n he oern emetures of ecreactor wil be cnsiere d Finlly the stbility of the otimueacto system wi e examined

A first thouht one miht concude that the mximum ermissiletemeratue shoud be emoyed in order to obtin hih reactionate s The best choice of temeratures will be consideed fte r teborato data hae been anayzed and the best recto flow tenhas een seected

ANLYI OF H LBOTOR TC DTA

Befoe studyin the different ossibe eaco flow ans thechemica kinetics for the chlorination reactions must be deried byeferrin to etinent iteratue references and by exainin theaaiable aoratory data The chemica eactions to be c onsider edae

C 66 l2 _ C 65I I

C 6HC +2 _ C 6H4l2 H

C 6HC l C l2 C 6H3C l +C

The iina memorandu indicates hat the rate euations for theseeactions may be written as

!Zlx (2 1 )t

LB = k 1xA k2B ( 2 2)dt

omation o tichloobenzene is to be nelected nd the mole frctin of dichlooenzene ll be assumed eual to

The lbotoybtch dt are to be coed wth intertedfoms the two rate eutions in dr tht he rate constnts mybe ealed fo use in otimizn the oeation of the thee rectos


29/236

o D Ozao nd ool 23

The desired relations between XA, xB' and t are easily obtained:

-= klXA; xA =e-klt (xA 1 . 0 at t = 0)

t

Sling his las, wih he cniins = 0 a = 0

kB (k k

k

3

(2 )

Vales f k ar s ea sl bae fr e labrar aa blng A s t n a selgarithc grah an rawing bes sraghines hrgh he ns f each he hree eerares

Een wih k knwn, here s aarenl n wa l he aa nB s as alae k b rawing a bes sragh line hrgh heee rimenal ns Accr ingl, Eq 2 s sle b ral bainale s f ? crresnng ach aa , an hes e are sl

0.-O. O 1I

:oN

Figr 2 Frsre kneic cn-sans f enzene chrnanSbls an eesen alesce fr eerental aa


30/236

2 Cp 2

ere ec emerue The rte constns so obtine re sfos:

40C 55C 70C

r 0 0 96 5 0 4 2 1. 55 r 0 0045 0 0 55 0 4 5

Fgure 2 so hes e re s icy n my e se nere beeen n. Fr 2 2 cec e ccn; t re cmre i cure cce y e se Eqs. 2 3n 2 n e bue r cnss .

Ti

Fur 2 Cnc enrn re r crn-on enzene . S ne r cmuerm Eqs. 2 3 2

een

Symbo e Frcon merure C

40

+ 5 5 0 B 0 B 5 5 B 0

SELECTION OF A REACOR FLOW L

Fe iferen f e sue emyng e hrerecr en n e ro semn eermine he opimum


31/236

Rco Dg Opimizio, and Cono 25

prctin csts Thes e prces s case s are:

1. Three r eactrs seies, reccle t the frst2 . Thre reactrs series, reccle the secn

3 Thre reactrs s eri es, reccle t the thir4 Three reacs in parallel5. atch perain

h batch prcess l be e s as t cmpare s pim prctin csts ith the prcin csts fr the fur cntins pera-tins The fie prces s plans liste her e are nt the nl pssiblealteraties Hevr, b fir st instiating thse seeral cas es shld be pssible t determine ths tpes prcess schemes hichrit frther cnsieratin

The cmbiatin f sparge chlrie and echaical aitatin mabe asse t ainta th liqi ell stirre in each reactr an tjust the assuptin tha the cmpsitin f the effluent stream ishe sae as tha f he reactr cntents Each reactr is a CSTR(cntins sirre a reactr), an the pratin ca be aalzeb th methds tline b Denbigh () a desc ribe in seealcheical eieer in texts Since the lme chane n reactin iser small the ttal les N present in ch reactr a be assme be th sae an cnstat

permit the selectin f an ptiu fl pattern each reactrill be as sume t perate a C The efec ts f ariatin te

perture ill b inestiate at a later stae

as I: Tree Reactors i See wh Recycle to e First

The first schee t be analze is represente b the flsheetf F 23 In re t achiee the mst sefl re slt, the prce sssh in this fiure ill be analze in a eeralize fashi Theneral results ma hen be applie easil t an specfic siuatin

Bnze recyc

T T5

XA XAZ XuBz_ x. XZ xl5fHd F

Ch Choi Chri

Fire 2 3 Blck flsheet f ctis stir rereactr sstem fr the chlriatin f benzene

Oiho- a'rihaobnzene


32/236

26 Chapter 2

Le F represen the rae b moles/our of feed of benzene o eirs reacor, incudng recy ce The analysis en procee ds as o-ows:

Frs eacr

1x --A -

+1

here Kn = INR/F, wth I based on e temperaure Tn in the thin his case, t irs) reacor.

FB1 = t (k1Xl -2XBl)

K11=

+K11) 1 +2

Second Reacor

x 1x -:2 - +K2 u) (1 2)F(XB2 xB) = NR (1xA2 - k2xB2 )

K1 2B2 =--=

+) +12) 1+22)

Tird Reactor

XXA3 =-1+K-13

( 2 5


33/236

eaco1 OLm:o oLl 27

I ll th acos oat a h sam tmauT T T ths ssns f n uc o

an

-

I

oss

2 . 6

2 .

2 8

Th annual costs f t qu oucn at o 8 mllonlbsa f mochlobnzn xpss ms 3 3

400 6 2 . 3 0 8 8 6 lb - mo s7 4 8 78

8 X 10 71 000- h/y 2 6 X X 8 mus b lss han o qual o 7000

(a Bnzn o monochlobnzn:

8 X 1 0 x 78 2 . 6

0 4 = $ 18 9 000y

(b) Bnzn fo chloobnzn $1 89 000 XC3!yearxB3


34/236

2 z/ 2

(c) Cln f mnclbnzn

8 0 X 71 x 0 04 5- = $227, 400/year1 1 6

Cln fo clobnzn

7 400 x ( C3 ) = 4 54 8 00 C3/yearB3 B3

nzn cycl c

8 0 x 78 (3 ) X3/ 0 0 5 = 8 00 ya1 1 6 B3 B3 pang cs c

4 0 . 9 0 4 0 0 x x e = $90 /a

Mbnzn

8 0 X 0 0 = $80 O/ya

Fx cas x 4 000 = $4 , O/ya

B tm nnal t t td t at a ntn " Ta T tta dtly a t a a d a s d l f an 70 tnn n t c n ad zn f t nant nz b l t tcnn l and c o bnz c bm x

F ptla ca n ll at ad t 5C a 8 m b appl t nt

0. 4 7 6 1 5 5[ =

F F 9

0 . 055 7 6 0 7[ F F 1 0

n 7 1 0 calns a bn ca t n d opz Ca n all a p C T lts a maz n Tab 1

Tb ndcas at a mn annua c a fCa n f a abt 5 b m a at m pat axatly 0 /a t b nt mnm n ta c c a y b on T


35/236

Table21

Resuts

oftheDesigCclatonsforCseI

Desigparmeters

F

1

2

3

40

1

1

7

6

.387

31

[2

.2

7

103

.69

08

.0414

A3

603

.179

.288

.74

446

xn3

86

62

.614

6

1

xC

3

4

169

98

.066

0.

9

12,

0

,44

3,86

3,17

2,780

Cstsdollrs/yer

+ch

38,40

8,4

38,40

384

b

49

320

22,30

63

18,20

72,6

3,6

39,20

e

22

39,0

0

72,7

f

12,00

108,0

,0

77,60

Tt

88,4

78,2

78,3

744,20

6

7

100

29

221

.

34

.296

.

27

:

2

49

6

49

O" to e s of ctO exttol! /'oe. m of te ct cmic bein cOlsire ( be ce /J o commca ct Som dl i t toW l e o oay dsign X/et i tei

yzng cemic engnr dt T i/01"t(C of tzin te/ 01 o /Jet vibe iZ t lio o esee/e1me o mJUszd

e si coputations i te 0 ia euato n h at tn osts bal inth dino o l op I cs o p el is rqe, l br us o ppxao gtss th cuto A o- sl o eocs ecooic s obte b is of mt case ii l lt b o t'cio e u

nay i any

nMh!

o: Michae Higgins rou LeaderFro Willia Sulivan Peident

As ou know, the coman i curentl opeatin a batch rocess

for the oduction of Fenway acid sat i ou Back Ba la FirstFenwa acid is roduced b ufonating Fen-arool-A with monochlorosufonic acid hi reaction is carried out in a tird-tareactor containing an aromatic olvent Sodium hdroxide is then

51


58/236

Cp y 3

added o e mixte to dce te stabe sodi s of Fenw aid;tis netaiztion is neces t event dosis f e sufonategou e sat is exacted ino waer and n amied to e

sodium sat of Bigon acid te desied end odctSince te aromatic soven owes te ied of te amidaion seit must be emoved before te reacion can roceed Moeover ahig e aromatic sovent is necessar fo e recce o e sfna becse water eacts wi te moncooslfonic acid hiseraion is at resen acieed b a cmbersme and cos seriesf wasing and striing oeratins carried ot n eac bac of odct

Since e bch exrction rocess is curen eraed a ecaaci and increases in oduct demand are aniciaed it is desied to invesigate e ossibili of a cninos exacion ea

tion o design go is reqesed o comee a eimina ocess design a wi aow e exacion of Fenwa acid o be crriedo n a coninos basis e resent bc eraion is caied uat 70C wi a H in e qeous hae f 8 Since on a eiminadesign is eqested o ma wis o resric or aenion to tesesme cniions oweve he manacring ecnica grou as bained sfficient daa o aow consideation f temperaes between20 and 70C and f vaes fo 8 t 2

e an as avaiabe sevea agiated kees tat cod easibe adped o a continos mixe-sete oeaion for te oosedexacion Since is eqimen is cren ide o ae reqesedto diec at east some aention to a contins mixersetter oeation oweve an ideas o m ve ab oe es of rocesseswod aso be apoiae

e desgn reqiemens f e secions f e ocess secife foowing:

1. eed t te coninous extraction and rificaion ssemafter addition f NaOH form e acid sat:

Aromatic sovent 3 000 bhrenwa acid salt 680 bhr

Ps negigible water wich accomanies te NaO2 Podct of te continous exraction and rification ssemo be fed to e amidation reacor :

Aromatic sovent 6 brenwa acid sovent 666 0 brWae 9 0 b

e foowing sections smmarize te dt reevant o o designwic ave been gateed b he ant technica grop

ou Wig

Aog b te Fenwa acid and e aomac soven ae comosed of mies f seveal comonenste wing aveage moe-


59/236

Proces im/JYoelt fo Lqud- Extaco

culr wegts ay e ascred to these copunds

Copoud

od salt of enway acd

Aroatc slet

Water

ut Nna

Mleculr

weiht

246

2

8

efers to the sod slt of enway acid

B low rat of th ottos or roduct tra, olehr

C Capacty of a proc nt, cu ft

Diaeter of a fractoatg clu, .

acty, at

F eed rate to a fractt colu, l ole/r

J Distriton or partiton coeffcentdieonlesL Lqud flow rat i a fractonatg colu, l oleshr

z Mass flow rate of a process stre, lr or quatty ofteral preset, l

Mlal flw rat of a process stra, l oleshr or uattyof ateral preset, oles

efer to te roatc et

T Tepratur, C

Vapor flow rae, l leshr or l/r Refr to watr

Mol fracton n a lqud pae

y Mle fracton n a apor pe

Per cent of te total Fenway cd salt apperin te aqeospase

Actty oeffcet

ercrit

Refers to a copoet t stadrd tate


60/236

Chapter 3

u

Refe cnen n he en hase

w Refes cnen he aueu haeD Refe he slen cnten f the tts srea f a fac

natn clun

s Refes t the arac en

Refe t the arac slen n the aueus phase

s Refer t he aaic en n the ranc hase

Rees he sent cntent f the erhead rduc fr afracatn cun

w Refe aews Refer ate n he anc hase

ww Refes t ae he aueu hase

uua olubili Daa

The utual sluites at 20C f the pure aratic sent andater ee taed fr the Intenatnal Critcal Taes. They are

Wae n len . 24 /10

en n ae . 19 /1

LudLuid ilibu Daa

An eeriental ra as carred u t estalsh he relatesluiiy f nay acd n he ater ad the sent hases A 2factra prra as carred ut the factrs and settn eels frhese eerients are a fls

act Leels

Teperature 20 and 70C

8 and 12

eh at 1. 0 and 2. 5

The da tned f these eerents are suarzed in Tale31


61/236

P IpO'le uu

a ul o LuidLqud tion udi

Exet I 2C = ; w/s = 2. 15

Auou a Oa a

Coont ole ol f K ole ol f

35 9 . 146 . 081 3 66 . 149 . 125

31. 6 1 99 . 55 . 325 22

1. 94 . 15 89 141 2 1. 14 96

356 4 1. 6 . 0 145. 4 1. 195 .

Experiment II: 20CPH 8; w/ms = 1.0

Auou a O a

Copot ol ol f I ol ol

A 3 . 533 . 45 3. 1 . 26 . 6

236. 13 . 995 . 991 55 . 269

3 . 1 . 54 242. 1 95 . 96

25. 13 16 2469 2. 43

Eeet III 2C = 12 mw /s 2 15

Auou ae Oan a

Copoen ol ol f K ole ol f

33 4 . 136 . 9 4 139 4

34. 5 169 . 991 . 546 34 . 249 21 . 985 . 05 144. 4 1 15 . 964

339 1. 5 1 4 4 1. 219 1.

Expet IV 20C 12 w /s = 1

Auou ae Oa a

Copot ol ol f ol ol

. 9 . 4 565 433 . 16 . 4 23. 13 5 . 993 . 44 . 46 233

563 . 46 35 2. 95 . 969

256 1 23 . 245 2 2 14


62/236

Chpter

3 sts f Liqid-Liqid Etci Sds (co.)

erent V 70C;

2 Aquous pase Oranic pas

Coponnt ol o f ol o fr

420 0. 171 0. 00972 4. 33 0 076 0. 047

313. 0 17. 40 0. 99 0. 537 0. 029 0 020

3. 09 0. 025 0. 0042 14. 0 1. 145 0 960-35 1 17 60 1. 00 45. 9 1. 192 00

Exriment V: 70C;PH= 8 1w/nS 1. 0

Aquous pas Oranc pas

Coponent ol ol fr oe ol f

14 10 0. 0573 0 00440 5 50 0. 0224 0 0107

T 234. 0 13 00 0. 995 1. 10 0 0640 0 006

0 25 0 0067 0 00051 246 0 2. 00 0. 9

24. 9 13 06 . 00 252 6 2 06 1. 00

pert 70C; 12 215Aqueous ps Oranc pas

Coponnt ol o fr o ole fr

39. 2 0. 59 0. 0045 3 20 0. 0130 0 010

336 0 1. 65 0. 990 0. 40 0. 0267 0. 0222

2 35 0. 091 0. 00101 4 0 1. 163 0. 967377. 5 1 3 1. 00 46 7 1. 203 1. 00

ent V 70C 2 nwm 1. 0Aqueous pas Oranc ps

Copone o oe fr oe oe fr

14 6 0 096 0 00474 4. 76 0 019 0. 00943 22 0 12 50 0. 99 1. 19 0. 066 0. 0323

1 1 0. 00960 0 00077 241 0 1. 960 0 95

20 12. 57 1 00 246. 9 2 045 1. 00


63/236

Process 1/)Ol'mt fo Liquid-Liqd

The tatstcs Deartent has anlyed these daa ng a standardcoter rora and has otaned the follown correlatn eaton:

{ = 6 11 9. : 56 425 (H 1) . 215 45) + . 47 1 56 (H 1)

9. 5 X 1 sw 1 56 5)

(H

0 T

45)

55 10-3 1. 56 (H 1) T 45) ( 1)where represents te rato of te ss of wter to te assof solet n ec atc extracton and deotes te ercentage of tetotal enwy acd whc s fond te aqeous se. Accordng tothe sttstcs group ths equaton s ald thn 9 per cet confdencelts for the rages of te arales oer wc the data ere taen.

Vo r-Lqd Eqr Da

Vpor-lqd eqlru data were obtaed for aqueous solutonscontag arous aots of aroatc solet and enay acd.Tese data sowed tat enay acd s rtally nonolatle at teteperatres of nteret n ths robe (approxately 105C) Dtwere otaned not only for xtres cotang rous aonts ofenway acd ut also for xtres hang dfferent lues of H n te

aqeous ase. As sown n g te relate olatt of te solent xtre s qte unaffected by te araons n and acd concentraton and all the data ay e correlated y a sge lne.

Cos Correlos d Des sros

The followng aproxate costcorreaton eqatons y e sefl n ealatng the econocs of ay of te rocess desgns to e

consdered. . 4 7 ()2. Cost of dstllaton tray = $16(). Cost of reoler = 47().4 Cost of condenser $15()


64/236

8 Capter 3

I7_)mbl

.6c- 5

Y4

32

'W

_17

9717197/. 1//.

pH :8 /81212 V/V. .4 6

'W

gure 3 -1 Vapor-lud eulru dta fosolet-wte xtures cotg ewaycd salt.

5. Cos of g a $150(C)o66. Cos of ettng ta

=40(C)O.7

7. Cos of lqud up = 300(m)Owere D dstllato colun daeer ( ,

= apor e (l/) ,

C = capacty of te (cu

as fow ate (l/r) ,8 Cost of contol fo a xe-settle coo $3,000/

extacon stage.

I s o e noted at tee euato yed ettes fo te ustal

ed eupet costs. Te stalled eupet cot ay e aproxated y ultplyg te ustaled cost y fou.Aoug e esdece e te xer-settle eupe wll

eetually ae to e asceraed y a detaled ass ansfer alyss, e followg approxate lue y proe usefu fo pelay de calculatons xer resdece e = 10 ute, settleesdence te 20 ues. A tee alue of esdence e, aoe-al stage effcecy of 100 er cent ay e assued. eferece(7 ay e cosulted fo dscusson of te fctor ta y affecte effcecy of xer-settler uts. A aerae specf graty of1 18 fo e two-pse xture y e used n coputng tereured eupe capacty

Low-pressure tea s alale a $0.80/000 l, d coolgwate crges are approxatey 002/1 000 allos Te coolngwate s aalle for 80, ad s desed to ntan e eperture se of t coolg wter at alues elow 40


65/236

oess Oe foy LdL Eto

PPOOF PE

Eto o Eeeta at

Befoe poceed a aalys of pelay pocess desgs, a exaato ad ealuato of e eeetal daa ode. Oe poat faco deeg e poces ecoocswll e e exet o wc wae ad e aoac solet ae uually solue Te utual solules wll e pacualy ccal, scete fal poduct specfcaos alow oy a al aot of sole te aqueous extact tat s fed to te adao eacto tep. Ayexcess solet us e eoed, ad ts sould poaly e accoplsed y a stppg o dstllato pocess.

Te ogal eoadu dcate at at 20C wae s solue te solet o e extet of 0 24 100 g ad e solet s soluen wae to e extet of 0. 19 100 g e coet tese aluesto a ola as, s useful to copae te uual solultes ofe pue soles w ose oaed fo e lqud-lqud extacostudes wc te acd alt was peset. copao s peeed ale 32

Te ut lute ate te oc e

eet epC H

Pue soles 20 00028 0. 161(lt alue)

I 20 8 2 5 00089 0272

II 20 8 1 0 00054 00269

20 12 2. 15 . 00058 00249

IV 20 12 1 . 0005 . 023

V 0 8 2 15 0. 00142 0. 20

VI 0 8 1. . 00051 0006

VII 12 2 15 0. 0011 0. 0222

VI 70 12 1 0 00077 . 0323

e data a 20C eeal ta e peece of te acd sa ad eaos H ae oly a odest effect o e uual oluleof two solets A costa tepeaue, te aaos H adsalt coceao do ot appea to poduce ay gcat o co

te cages n te uual soultes he cate te daa oaed a 70C ay ase fo dffcules atag accuateepeaue cool at e ge leel of epeaue. o te pupose of a pelay desg, e efecs of H ad sat cocetaow e egected, ad aeage aues of e ua soues wll


66/236

Cp

be ssumed o pp ech emperure lee hese men uesof d s re s foows

emperure w

000059 0025

000093 0025

Afer he desgn hs been compeed, i w be imporn o nestige he effect of rions in e lues of x nd ws on heesimed process economics f rions of he mgnude sown inbe 32 re found o ffect he esimed finnci reurn sgnificn more exc eerimenl eerminon of the muul sou

biiies wod be required

Cosderio o e LqdLqd Eqlbrm D

he ppcion of fcoril experimens s er powerfu echnqe in obnig nd correing expermenl d for design workUsng ssc mehods gret del of informion m be gheredb expendg on mimum of eerimen me nd effor esemehods re pricr epfu when he heorecl bsis of pro

cess operon s poor undersood efeeces 45 sere sn exceen nrodcon o sisicl desgns d er ppcono prcicl cemcl egneerng probems

B se of ssicl mehods q 3 hs been dered s heproper correng eqon for he eerime ress so nbe 3 his equion rees he frcion of he o Fenw cdfound in e queous phse o rions in e emperure ndmouns of solen presen s se in crrg o design ccuonspresens wo er gnificn dffcues Frs e ld of heeqon is imed o he rnges of he ribes for which he orign d were obined is quie possbe h he design specfi

cions wl reqre he ppcon of he correng equon welbeond he rge of rbes for which he d were ken For exmpe e ro of wer o solen ws red b on fcor of 2 ne boror eermens d i is une he opimm continuous process woud hppen o correspond o soen fow res nhis rnge Appcion of he eqon ousde ese ims woud beqie risk nd cod ed o hgh erroneous concsons

he secod dfcu somewh reed o e frs resus frome poor seeco of ribes h were used in seng up he experimel desgn d n expressng e experime resus heseecion of emperure d s rbes ppers o be resobehoweer e use of e rio mms hs no resonbe bss d hequni does no pper o be n pproprie rm of he responseribe For exmpe if er rge ues of IW ouide hernge of he origin d were nsered n q 3 ues of > 00per ce cod be obned hs sor of psc impossb mgh


67/236

Process Improveent for dLqd ExlYao 6

a g tced t qat ad e ced wt ter algrac xprsss w f ts srats s wrthwl sarc fr a r satsfactry ass f xprssg t xpretal

rslts fr prcdg wt t dsg csdrats a trdyac syst wc a slt s dstrted etwetw scl slts, eqlr wll taed we t ccal fgacty f t cpt pas ces qal t t fgacty f te sae cpt t ter pase e s ccpt sappld t t prst cas,

wch tr ay add as

fA'lVxV os S

Trfr, at qlr tas

3)

Nw t fgacty f a cpet ts stadard stat, s depedetf cpst, ad a csta tperatre Eq 3 ay wrtteas

33

dt slts, t actty cefcts ay assed t depdet f ccetrat, ad a futer splfcat s effcted,wry

(3.4)

T quatty] s tered te dstrt r partt cecet, adE3 4 s cetally k as ersts l t pres qut usefl crelatg e resuts qudlqud exrc eerest s t e recgzed tt te dsrbt f eay acd etee tet pases s t detered slely y pyscal peea ce aeuaza eac s s tg pce, e sp fr f q34 s t srctly appce Heer, as a tal apprxat tay result a dt crrelt tat ll e usel fr prelarydesg calcats

Castg t daa f Ta 3 t fr suggstd y E 3 4rsults t daa lstd Tal 33 Ty dcat tat part


68/236

62 Cp

Table L et Daa Esin the Form of a Partition Coeiciet

xement TemetC XAW/XS

I 2 8 65

II 8 66

2 2 699

IV 2 6

V 8 66

8 4

2 .8

III 2 . 3

tion cofficint is indpndnt of d th rativ mounts of solvnt h vr vu of th prtition coicint at 70C is 0.590,whi tht t 20C is 0.663; ony a 10 pr cnt vrition is found ovra 50C vrition in tmprr. his is proay not atistcysiicant in viw of th scttr in th ta at t ighr tprr

v. hror Eq.3-1 ay dicrd, and th iquidiquidxtrction data may rd in trs o a sig vrag vufor th prtition coficint 63. Sinc th prtition coficint hsn found to quit inriant ovr a wid rng of rimntconditions t sinr my us tis vau coidnty for ryany dsi condiion his rod appiction oud not hv possi th dsign clcuations wr to ad on Eq 3-1

h rsuts of is dicussio phaz n or o judgnt th ctio of t propr o for corratg rita at h us of sttitica rit s a ai t it s ot a suitt or a ma aasi of a

pro so t out at t r o th t ho a 3-1 ar cotioy corrat i orm of trrdiagra as utrad y Houg Watson, an Ragaz Hovr th prs tuatio th concnrations o ot ar smat triar iagra o nitr aninu nor f.

Vpor ii Ei t

Te viqi qiibim dt e be e esented ney cete ige s be decty icbe edesign ccutin In tc te etive ivince o te etve vtiy t cges i nd eny cid cncettin i vey cveient ete o te dt n i ge ty edce te eed cmtt et


69/236

Poss Io for LqdLd Extrco/ 63

PREAY PROCE DEGN ALCULATIONS

To odce eny cd odct havng the ecified ty

oce t ccolih the fig objective tct the cid at om the oatc lvent2 Remve the otc ovent om the eo ci t

ot o to the amidatin te

Sice te igial emadm cified tat a cti eette dein d be cnideed a oce of the tye hn inig 32 d be aiate In thi deign chee the feed teactii te cde ea acid t i mie it cce aia at ad te cmbie team i mted cti it te

Feed steam

A' 680 Ib/hr 3,0 Ibh

Oganipose

RofQle se(Sve ecyce)

A 14b h 2 94.4bh

Auxowae

Oaos

Aquese

Aqese

ige 2 Bock ow igm o onetage ntus etcton oce

me The ffent fom the me te into gnic andae hae in the ettle The al ont of iovd oganiclvent in the e hae eove by tie f hch theinl deied odct i eved It mtat to nt tat the tem fed to the tie i aated ith ogaic ovetd fthe tht the ta bity of te ate ad lvet teineitive to tete tin Theefe a ctying ecton ee dd t the te a the ate ch ectin dcnta tae liid nd no enichent cld be efected thi ean the ce i hve to be deine o that the deeddct ity c be ceed by y tii ecti Teead dct fm te tie i cded a aated Te


70/236

Chpte 3

aqueous pase from the condesate settler serves as te recycle

waer strea and is returned to te mixer, while te organic streas

leaving boh he frs and second selers are combned, sent o a de-

hydraion si, and reurned to e sulfonaon reacor.Te pesen des l conside al aspecs f the sepaatn pocess excep he dehdaton ut f e aoac eccle; he cstsassciaed wh this lae opeain ae nt expeced to be sicant.As a fist csdeai a design ill be aazed at copaesone me ad wo setles as sown n Fig 32 Cleal he economics of te pcess design cod be aleed ncan the useof addtnal pais of mxes and setles Tis concept wll e exaied a ae sae f he aass Depedn n the nbe fsages eqied he mxe-sete opeao, ne t sh tocnse he se of an extacon cun Again hs decs wll be

defeed ui the cptations f the elimna mxe-sele desgn cases have been copleted and analzed As a fthe nial apximan, the pcess will e assmed opeae at 70C ad a o 8 Hee, jdg the esus shown in Table 3, aationsn hesearameers would not be expected aect the ecomics ofthe process eriusly.

Te aaysis e desi sw g 2 prceeds i a aner qeanalogs o at for mos separat operas-by ealternae applicatio ofaeralbalance andequilbrimrelaon-sips. Frs f al the compsiin ofte recycle sream maybesablished araly by over-all merial ala

ces on componensA

and :

A lost n recycle of rganc solvent= 680 - 666 14 l/r

Sn recycle 3000 - 5 6 = 2, 994 4 lb/hr

Noover-allalance n water s yet pOSSibe, since the lw ratef theakeup water stream as not yeteen deermned.

Focusngaenton on hemixerseler un,i eqilbrum s at-taned e relatnshp smmarzed y Eq. 34 may e assume valid:

n xA n n-= = 0 . 63

xAS lAS(nAS l nSS ) 35)The qaiies desied b l epesent te oal flow aes of hesteams ea te e-setle cbiati

As a fist appimai e al slbiies f wate a sletma be assmed to e negle. The validt f hs appoxan

will be deemned b a second teaon on he calculatn qan a e ewite as

3 6


71/236

ro rovn or Lqd-Ld Exron 6

h

nss = 000/1 = 4. 4 mo/h

666/46 2. 1nS 14/246 0 0

Thfo

nww = . 1429 10.

= 841 mo/h

o mww 200 /h

Wth th nta aomaton t ob to account fo thmuta obt of at an ovnt In th anay o th mnta ata takn at 0Cth foon mutua uty v tabh

Xsw = . 0009

xws = 02

Now th foon vau may comut

sw = 0 0009 2. 1 1841 w ) b mo/h

1sw = 1 b/h

nws 002 4. 4 0. 0 ws )

Ilws = 2446) . 02) /. 92 = 0. 69 b mo/hs= 1 /h

Wth th vuth fna mata aanc on th oc may tah

ss = 4 4 = . mo/h

= 1841 . 69 = 1840 mo/h

Th auay at tam may no tmn aomatyy an ova mata aanc a

Au at 199 1 5 00 /h

= 1116 b mo/h

an th cyc at tah a

Rcyc at = 1841 111 6 19 b o/h

1 0 /h


72/236

CzapL 3

d o g oln ay now alad

Coonn ol/ /

71

184

1 7

666

331

1

and vaor o ondener a aroa ro aara n alaon

Coonn l o/ l/

A

S

179

1 68

1

6

A a rh e n alulaon, an aoxa aralalan on h ondna el rl n:

s

93 179) 1. 61 l ol/r

n 1. 68 1 61 . 7 l ol/r

Now a h aoa low rae o all rea hav en alhd, a eond raon n h allaon hod al h lowa wh en vald o relnary ono evalonFr, aoun o olvn n he oran ae eod, ngno aon olven n h reyl wer rea:

ss 4. 4 . 7 1. 6 4 3 l ole/r 99 l/r

And war low a n aueou ha alhed a[1 (24 3/0 057) ]Iw - 1.0

0 63. 71 = , 83 l oe/

33 l/r

Prng h allaon rodr led rvoly

Is . 093 71 18 + Zs) 1. 706 l ole

s

1 l/r

(. 275)Iws 4 3 57) . 688 oler. 975

W 1. 4 /


73/236

P 1J r Liqdqu Excon

Aux wte 1 99 12 4 2 00 lbh 1 6 l mes

Recycle we 1 832 111 6 120 lb mlesh 3 000 lb

e secod oximt of the feed to the sti colm sdelieted Tble 34.

e Fd o t ou

omet l es ; l

W 1831 . 99 6 33000

1 0 . 93 210To 183416 1. 0

Te ieive ocede cold be sed b he vles bledd devie igificl f hse id i he fist ieiThe meil blce clculis hve bee cmleed

Stipp Dsi

Te feed t he sie is seciied b Te 4 d he miimmequieme f duc i s sh i Fi 32 Sce ms f heomic sve will be e ovehed he li mll flw ese edl esbished

F 183. 4 lb es/

121. b oes

B = 113. b moles

d mei bce o the sve ields

1 06 121 y 113 X (3

w thee e lmits t te values e d emximum tleble vle f s secifed s 0 000 ad fmq 3. the cesdi ve of' is 0 000 At he extee if ite ses wee used wld be 0 d wld iseto 0. 00099. leal this age of ccettis des o allw a sifict vti the se f ste he bil e is essetillfixed b vel stie blce wich i t esls fom hesecificti e-ste ecti cess his ei he csethe stie i this istce is desied iie is citl cstie l oe idel stge s tilied Bsed e se d L ti f 8341 = 0te cbeiele dm fthe ste desig s shw i Fig 3


74/236

8 Gz/

000

000

000

0005Y

000

000

000

2 e L/V eQe e /V

O. Ic )0

Figue 33 MCaeThiele nstrutin r thelsed steam srippers used n three extatn ases Trial and errr was use t tain an ntegral nue f stges for ehase w B " 0004)

The llwig psts were derved y trl and errr fr thsfigre ad rm q 3 7:

XB . 0001

00983

Qualtatvely ths result means hat the large amunt water thatust e reved ad the hgh relatve vlalty the system ausevrtully all the amt slvent to e taen verhed n the stripperAtlly, the ateral alane fr the mersettler unts ght e

mied to lde hs hange n flw rate, ut suh a oputatn srly t wthwhle

UMMY O ATL BALN TPPEALULAION

As ened efre, the ress shwn n Fg. 32 may e ded y us mulile ixersettler units Clearly the adtn suh uns will derease he requre quantty f reyle water andthe rrespdn stem usage. Fgre 34 shws a three-stageer-setler ress a extensn t the egns s vus rmths figure.

Iteratve ateralalne alulatns and strper desgns haveeen pleted r extran presses havg ne, tw, an three


75/236

PYoces Imprv1lt foy Liqud-i Ext)actioJ 6

Mixesee

NO

Mlxe-

seeNo.2

Mxe

see

N3

Rffne sem(Soven ecyce)

Axwe

Aeosecce

Aqueos extrac

Conensesee

ppe

Podc sem

Fe 3-4 }low daga fo a heeage exacio oces

age The comuaos fo ulle exaco sae ae queaalogos o hoe alead eeed fo he igleae exacoThe calculaos fo he sppe des ae mmazed g 33I he sippe desig fo he woae exacio a sao aseshich aaloous o ha ecouneed i he pe desi fo he

oeage exaco e he ue ad low lmis o ae ealequvale As efoe a e havg oe deal age dicaedHoweve he se desg fo a heesae eaco poceshe lm o va fo 004 o 00 ad a sozaos ed fo he oo deeao of he deed e ofsppe saes ve o, hs sace he capal ad opeaigcos fo h sppe ae o mal ha he me o ippesae a be abiai seeced wii e ims o v se b eaeal lace A ch the L/V ao h cae has ee vaed al ad eo l codios fo wo deal sage have eeesalhed

A dcaed i he ogal memoad a sae efcec of10 e ce s aued he xeele I he case of heppe a moe coevave ad ealsc vae of 0 e ce saed fo he oveall ae efficec U hee effcecesoe oa he eul uazed Tale 3


76/236

70 Chapt 3

Tabl 5 ul o i Cauaions o Cass Havng On,Two d T xaion Sags

Ne of etacon stages 3

Wate eccle te /h 300 243 2

Aa wae / 200 200 00

Total wate te l/h 300 448 262

Vapo ate n stppe lh 300 2480 6

tppe oveea coposton Yv 0. 000983 0 0060 . 005

olent content of podc B 0 0005 0 008 0 000295be of ay n stppe

Nue of pups eque 9

it tis mti t is a sime mte t memet te esn cte pesente n the oii emod a o estmte capactes reqre fo the xe a settle ts a fo thestppin colms The cpitl costs fo pocess eqpme then folo diect fo the cost-coreation eqtos vale n the

eoandm Afte the cta estte te pcpa opeti costsfo these desin cases a e estalse Te jo ec opetg costs ae those fo stea nd cool wate; fo the foatonspped in te eo these costs a e estmte a

tea cost 6 4 ollas/ea

C I cost 0 48 ollas/ea

whee V s te vpo ate n the stippi t eessed lh.The eslts of al the pem ecoomic cctos ae lsted

Tbe 6 t shold e note that opeat costs sch as loovehe nd mntence a not sow Hoeve the aj aleopeat costs hve een ten nto accont aclatios of tetpe swn povide a esoae ass fo comain vaios pocessatetves

OZO OF E -LR R

Te 36 dcates tht te econocs of the oose etcton

pocess are ver sto fcton of the wteecce te. tppes tat additoal ecooes cod e effected fthe ections the wte fo te wit coesod creases n eqpet cpitl costs n the lmit an fiite mbe of staes weeused te folog mplemetation of q 3 6 ol appl to the fst


77/236

lO'l fo- Lqud Eo

Table Economic Evauaton of Processes Haing One, Twond hree Extraction ge

Nb f eact ge, 2

Ca2it ct tteN

M $20 $1726 $216

, + 1 e 2880 500 6001 bo 560 060 101 Condense 400 165 40

3( + 1) p 760 500 62F. 3-3 Tays 00 74 90 Conos 000 6000 9000

To pced eqipn 26 0 1975 2206

Toa nsad qipn $104440 7500 $88424

ng cos esie

Dpcaon 15 p cen $15680 $ 600 100

ea, 6 4 198500 5900 1700

Cooig wae 8 1900 190 0

oa opaig cos $229080 $28690 $50doasya

xe-see sage (e sage o wc e es Fnwy acid-soven ie d

1 + (3000/12)/(680/246)- 06 (66626

Soving s qaon sow a inm w fow e of9 6 b moh o 1 b qd o cop e spaonvn f n infi nb of sges s izd Since s v sss n a qied n f podc i s ce he aonof axiy we w v o be dcd n e s of g nb of sges o be exnd n sc sncs kep wcod b ddd o podc a af sippng s bn copd my be so qi esiy a o n excionsags e sd ow a o s n 2007 b w b eqid ad a cospondng decas n axiiy ow s bffecd


78/236

72 CwjJ 3

In order to complete the electin of the optimum prce calculation hae been carred out fr four- and eight-tae extractionrocee For tee conditin te folowng reult ae been ob

taineNumber of extraction tage 4 tage

Total ater fow rate b/r 16

8 tage

00

In bth tem the water flow rate redued far below that required in te final produt tream The preent calculatin aumethat the olubilt of Fenwa acid at nt beng exceeded Theaidit of thi aumptin wll hae to checked an poceehaing a large number of tage apear econmcal ignificant

Since direct operatng expene are negigible for the four andeight-tage peratin te fncial ealuatin for them i traightforward Cobining thee ealutin with thoe ummarized inTable 6 the proce economic hae been optmized accrding toFig 35 which hw tht either a three- or a fur-tae unit couldbe ued wit coprable ecnomic reult n oder to aoid anprblem that a reut fom exceeding te lubilitie of the Fenwa cid alt the theetage unit i a d electin fr ti pemina deign

!

! < N

+

+

1-(0'- c,,I ad cg"acToto o fo ot I Ib hr

Figue - Financia ealution of eetti pe

MMY OF T DIGN SLTS

The reult ummazed in Fig indcate that te eiedeparatin culd be accoplihed b a tee-tage mixer-ettler

roce cheme. The requred capital outla would be approximatl


79/236

Pocess Impovent fo Liquid-Liqi Extrto 3

88 00 nd he comed nna oeig cot fo he excionoce i abo 00 which coeon to 0/l of acidat A menioned evio hi oeaing cot doe not icde

evea imoan iem ch a bo ovehe chge eqimentmintennce and ovent oe. icu he cot of oventoe i ofen qite an imoan conibo o he oeag cotof n exacion oeaion. e ddition cot em ee incdedhe eing ota conveion co obb wod och . /ba vae coe o hoe inced fo he e of exactionoetion being conieed in he eent ce Since mo of thediion cot e qie nenitive to the nmbe of extactiontge it i nike tha he ncion of hee facto wod ce aignifican ateaion in he oimm oce deign a h beeneected

Since on ee mixe-ee ge e eqied it i dobtha a iqiiqid excion comn wod ave a ignificn advange ove he ooed deign. Howeve Tbe 6 how athe cot fo conoing e mxeee oetion eeent age faction of h ota cai invemen Thi nvetmen mighte be educed b e of an exaction comn hi oibiiy hobe examined n beqet deign cacuion

Some mion mde n he eimina dein nayi hodo be inveiged in emoe detied dei efo Fit ofa he eidence-time vae ued in izing the mxig equimenthod be ecace The vae e ae thog o be eonbebt e nd he c

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The Industrial Practice of Chemical Process Engineering