Plant Layout & Fired Heaters

BN-DG-C01G Plant Layout - Fired Heaters T abl eofCont e nt s 1. General 2. Location 3. Safety 4. Inlet and Outlet Pipin 5. Burner Pipin 6. Deco!in and Soot"lo#in 7. Instru$ents

1% General 1%1% Function Thepr i mar yf u nc t i onofafi r edhe at eri st os uppl yal l heatr equi r edb yt hepr oc es si nonef or m orano t her .Afi r e d heat erut i l i z esgas eousorl i qui df uel sof t enpr oduc edasab ypr oduc t .Thenor mal pr oc es sf unc t i oni sr ai s i ngt he pr oc es ss t r eam t oi t sr e qui r edt emper at ur ef ordi s t i l l at i on,c at al y t i cr e ac t i on,et c .Si z esofheat erv ar y c o ns i d er a bl y , de pe nd en tup ont h et y p eo fdu t yan dt hr o ug hp ut .

1%& 'ypes Ther ear et woge ner al bas i cdes i gnsort y pesoffi r edheat er s : •

Bo xt y p e

•

Ver t i c al t y pe.

Ei t herofwhi c hma ybef or c edornat ur al dr af t . BoxTypeHeat er s  ( Se eb e l o wfi g u r e s2a n d3 . ) Abo xt y peheat eri scons i der edt obean yheat eri nwhi c ht het ubesar ehor i z ont al .I nt hi st y peofheat eri t i spos si bl et oha vel oc at i onsorz onesofdi ff er entheatdens i t i es .Thez oneofhi ghes theatdens i t yi st he " r adi ants ec t i on" .Thet ubesi nt hi ss ec t i onar ec al l ed" r adi antt ubes " . Thehe atpi c k upi nt her adi a ntt ubesi sma mai nl ybydi r ec tr adi a t i onf r om t h eheat i n gfl ame.I ns omeh eat er de si gnss hi el dt ub esar eus edbe t we enr adi antandcon v ec t i onsec t i on.Thezoneofl o werheatd ens i t yi s t he" c onv ec t i ons ec t i on" .Thet ubesi nt hi ssec t i onar ec al l ed" c onv ec t i ont ubes " . Thi sheatpi c k upi nt he c on v ec t i ons ec t i o ni sob t ai nedf r om t h ec ombus t i ong as espr i mar i l ybyc on v ec t i o n. Bo xt y p eh ea t er sma ma ybeu pfi r e do rd o wnfi r edwi t hg asoro i l fi r e db ur n er sl o ca t e di nt h ee ndor s i dewal l s ,fl oor ,r ooforanycombi nat i ont her eof . Upfir e dHe a t e r s I nt heh or i z ont al upfi r edh eat er ,pr oduc t sofc ombi nat i oni nt her adi at i onc hamberpa ssupwar dt hr ough ba nk sofr o oft u be sa ndafi r eb r i c kdi ff us e ri nt oap l e nu mo rc o l l e ct i n gc h amb er .Fr o mt h ep l e nu m

Suc hh eat er sma ybefir edv er t i c al l yupwar dbypa nel s ,mou nt edi nt heheat erfl oororhear t h,t heheat er fl oorb ei n gel e v at edt opr o vi deheadr oom b eneat h.Al t er n at i v el y , t hes ehe at er sma yal s ob efi r e d hor i z ont al l ybybur ner smount edi nt heheat er endwal l s ,i nwhi c hc as et heheat erfl oori sonl yel e vat ed ab ov egr adet opr o vi deai rc ool i ngc on v ec t i ont ot h eheat erf oun dat i ons .Thi st y peofhe at erma yc ont ai n s i n gl eo rmul t i p l er a di a t i o nc ha mb er sdi s c har gi n gfl u eg as est oac ommo nc o nv e c t i o ns ec t i o na nds t a ck . Downfir edHeat er s I nt h ed own fi r e dh ea t e r ,c o mb us t i o ng as e sg en er a t e di nt h er a di a ntc h amb erp as sdo wn wa r d st h r o ug ha r e f r ac t or yc he ck e rh ea r t hi n t oac ol l e ct i n gc h amb erb en eat h .Fr om t h er et h efl ueg as esfl owu pwa r d t hr o ug ht hec on v ec t i ons ec t i onan dt h enoutt ot h es t ac k .Thedownfi r e dheat er sar eb as i c al l yi nt ended t ofir eonhe av yr e si d ua lf u el s ,wh er et h efl u eg as e sar ec or r o si v ean dma yc l o gfl u eg asp as s ag eso f c on vent i onal heat er s . Con v ec t i ons ec t i o nsar et huspr ot ec t edb yr emo v al o fc ombus t i ons ol i dsandar eu sual l ypr o vi dedwi t h i ns pec t i onpor t s ,s ootbl owi ngdev i c esandt ubef ac i l i t i est ok eept hec oi l scl ean.Bur ner si ndownfi r ed he at e r sar ea l wa y smo unt e di nt h eh eat er e ndwa l l s . Ver t i calHeat er s  ( Seebel owfi gur es4, 5and6)Ver t i c al heat er sar eei t herc y l i ndr i c al orr ec t angul ar .They ma yhav er adi ants ec t i ononl yorc onv ec t i onandr adi ants ec t i ons .Ther adi ants ec t i ont ubeswi l l us ual l y bev er t i c al ,buts omec yl i ndr i c al heat er shav ehel i c al c oi l s .Thec onv ec t i ons ec t i onc anbeei t herv er t i c al ofhor i z ont al . T ype sofHe at e rF i r i ng Heat er sc anbefir edf r om anypos i t i on,i . e.bo t t om,t op,s i deorend. Byf a rt h emo s tc o mmo ni sbo t t o mfi r e d,ma i n l ybe c au s ei ti smo r ee c on omi c a l .Th eb ur n ero fab ot t o m fi r edh eat erwi l l bel oc at ed2. 12 . 7M abo v egr adeatahei ghtwhi c hi ssui t abl ef oranoper at ort owor k un der n eat h .Op er at i ngf r om undert h eheat eri smor edang er oust hano t h ert y pesoffi r i ng,whi c hi st he pr i nc i pl er eas onc er t ai noper at i ngc ompani eswi l l noti ns t al l abot t om fi r edheat er . Heat er sar ec ommonl yl i ghtwi t hanel ec t r i ci gni t or .s omer efi ner i esus eapr opanet or c hwhi l es omes t i l l l i ghtt hebur ner swi t har ags oak edi ns pi r i t sork er os ene. For c edorNa t ur a lDr a f t Co ns i d er a t i o nmu s tb egi v e natt h el a y ou ts t a get oa cc o mmo da t et h ea dd i t i o na le qu i p me nta s so ci at e d wi t haf or c eddr af theat er .Thi swi l l us ual l yc ompr i s eanai ri nl etduc twi t hs i l enc er ,f or c eddr af tf anandan ai rpr eheat er .Thei nl etduc tma yr equi r eas uppor ts t r uc t ur e.

&% Location He at e r sa r eal wa y sl oc a t e da tas af edi s t a nc e15me t er sa wa yf r o mo t he rh y dr o c ar b onbe ar i n ge qu i p me nt andpr ef er abl yupwi nd;howev er ,ons omepr oc es si ti sper mi t t edf orr eac t or st obewi t hi nt hi sdi s t anc et o pr e v en tl i g htv o l at i l ev a por sf r om b eg i nb l o wnt o wa r d sa no pe nfl ame . Sp ac emus tb eal l o we df ort uber epl ac ementf orbo t hh or i z ont al andv er t i c al he at er san dt hi s ,t og et her wi t hamp l eac c es sf o rmo bi l eeq ui p me nt ,s ho ul dbec on si d er e do np i pi n gl a y ou t sa nddr a wi n gs .Amp l e ac c es si sal wa y snee de df o rfi r e fig ht i n ge qui p me ntwi t ha r e asund ero ra r o un dh eat er sus u al l ypa v eda nd c u r b e d . Nol owpoi nt si nt hepa vi ngorgr adi ngar eper mi t t edast hes epr ov i dee xc el l ents por t sf ort r appi ng h y dr o c ar b onl i q ui d swh i c hc ou l db ei g ni t e db yt h eo penfl ame so ft h eb ur n er s .

(%1 Snuffin Stea$ Station Se eb el o wfi g u r e7 . Sn uffin gs t e am c o nn ec t i o nsar es u pp l i e db yt h ehe at erma nuf a ct ur e r s ,g ene r al l yi nt hec omb us t i o n chamberandheaderboxes . Thecon t r ol poi ntors nuffings t eam mani f ol di sgener al l yl oc at edatl eas t15me t er sawa yf r om t heh eat er , i ss uppl i edb yal i v es t eam h eaderandi sr eadyf ori ns t ant aneousus e.Smot her i n gl i ness ho ul dbef r ee f r o ml o wp oc k e t sa nds h oul db es oa r r a nge da st oha v ea l l dr a i n sg r o up edn ea rt h eman i f o l d. Col l ec t edcondens at e( a par tf r om f r eez i ngandbl oc ki ngl i nes )c an,whenbl owni nt oahotf ur nac e,r es ul t i ns er i o usda ma ge .( L owp oi n t ss hou l db edr i l l ed1 0mm d i a me t e ro rpr o v i d edwi t hs pr i n gop en i n ga ut o dr ai nv al v es ) .

(%& )onitor No**les Somec us t omer sr eques tt h att ur r e tormo ni t orno zz l esbel oc at edar o undt heh eat ers ot hatwat erf or fi ght i ngafi r ei si ns t ant l yav ai l abl e.Cont r ol sf ors uc hnoz zl esshoul dbel oc at edatl eas t15met er sawa y f r om t hehe at er .

(%( +tility Stations St eam,ai rands er v i c ewat erc onnec t i onss houl dbepr o vi d edneart ubee nd sofheat er s .3. 4 .Pr oc es s Con t r ol St at i ons Pr oc es sf ee dandd i s c har gi ngbl oc kv al v esandfl owc ont r ol v a l v ess hal l bel oc at edata di s t anc ef r om t heh eat er ,i fi ndi c at edasnec es s ar ybyt heengi neer i ngfl owdi agr am ori ns t r uc t edb yt he Pi pi ngSpec i al i s tEngi n eerorPr oj ec tDepar t ment .

(%, .plosion Doors Pi pi ngshal l notobs t r uc te xpl os i ondoor sort ubeac ces sdoor s .

/% Inlet and Outlet Pipin Se eb el o wfi g u r e s8a n d9 . Fl owdi s t r i but i ont hr oughamul t i pas sheat eri saffec t edbyt hei nl etandout l etmani f ol di ng.Thepi pi ng ar r angementatt hei nl etoft hef ur nac ei st hemor ec r i t i c al andr equi r escar ef ul at t ent i on.

/%1 Inlet Pipin I nl e tpi pi ngs ho ul dpr ef er abl ybes y mme t r i c al an do ft hes amel engt hf r om t hep oi ntwher efl ows pl i t st o t heheat eri nl et s .Thi sr ef er st ot h enumberofbends ,el b owsandv al v es ,aswel l ast henumberofs t r ai gh t r unsofpi pea ndt hei rl oc at i on .pi pi ngsho ul dav oi ddeadendt eebr anc hesan ds har pt ur ns .Uneq ual fl ow t hr oughan ypar toft heheat erwoul dr es ul ti ndepos i t sofc ok eando ver heat i ngoft ubewal l s .

/%& Outlet Pipin Onout l etpi pi ng,s ymmet r yi snotasc r i t i c al asont hei nl et ;howev er ,nons ymmet r i c al pi pi ngma y c ont r i but et opos s i bl ec ok i n gando v er heat i ngoft ubes .Ano nr et ur na ndas hut offv al v ei sus ual a tt he out l etoft hef ur nac et oel i mi nat eanyr ev er s ei nt hec as eoft ubef ai l ur e.

/%( Fle.i"ility Bec aus eoft hehi ght emper at ur ei nv ol v edandl engt hofpi per unsr equi r edt oi s ol at et heheat er s ,pi pi ng fl ex i bi l i t ymus tbee x ami n edc ar ef ul l y . Somehe at erma nuf ac t ur er swi l l p er mi tal i mi t e damo untoft ube

mo vementt ot ak eal l orpar toft hepi pi ngex pans i on.Thi spos si bi l i t ys houl dbei nv es t i gat edi nc onj unc t i on wi t ht heSt r es sDepar t ment ,b yt hePi pi ngDes i gnOffic edur i n gt hest udys t age.I ti sgen er al l ynec es s ar y t oanc hort hepi pi ngadj ac entt ot heheat ert or emo ves t r es s esf r om t h enoz z l es .

,% Burner Pipin Se eb el o wfi g u r e s8a n d9 . Suppl yoff uel t oi ndi v i dual bur ner si sadj us t edbyi ndi v i dual v al v es .Thes es houl dbes ol oc at edt hatt he b ur n er sc anb eo pe r a t e dwh i l eo bs e r v i n gt h efl a met h r o ug hp ee ph ol e so rb ur n ero pe ni n gs . Al l bur nerl eadsf org asandst e am ( at omi z i ng)mus tbet ak enf r om t h et o poft heheader s ,a ndf uel g as pi pi ngs houl dbes oar r angedt ha tt her ear en opoc k et si nwhi c hc ondens at ec oul dc ol l ec t .Thef uel o i l headermus thav ef ul l c i r c ul at i on;undernoc ondi t i ons hal l i tbeade ade ndl i ne.Nonc i r c ul at i ngbr anc hes t obur ner ss houl dbeass hor taspos s i bl eori ns ul at edt og et herwi t hat omi z i ngs t eam. Ar i n gh ea de ra r ou ndt h ef u r n ac emo un t e das hor td i s t a nc ea bo v et h ep ee ph ol e s,h av i n gv e r t i c al l e ad s adj ac entt ot hev er t i c al door st ot hebur ner s ,pr ov i dest hegr eat es tdegr eeofv i s i bi l i t yf r om t heoper at or ’ s poi ntofv i ew. At omi z i ngs t eam t obeus edi nc onj unc t i onwi t hf uel o i l s hal l b et ak ent hemai ns t eam s uppl yheaderator neart heheat er .St eam t r apss hal l bepr ov i dedt odr ai nal l l owpoi nt si nt heat omi z i ngs t eam s y st em. Se par a t el e adst oe ac hbu r n ers h al l b et a k enf r o mt h et o po ft h ea t o mi z i n gs t e am s ub hea de r .Sh ut o ff v al v ess hal l b es ol oc at edt h att he ycanbeop er at edwhi l eobs er v i ngt heflamesf r om t heob ser v at i ons por t s .

% Deco!in and Soot"lo#in %1 Deco!in ( Se ebe l o wfi g u r e1 2) Thei nt er nal c l eani ngoft ubesandfi t t i ngsma yb eac c ompl i s hedbys ev er al met hods .Onei st oc i r c ul at e gasoi l t hr ought hecoi l af t ert heh eat erhasbee ns hut do wnbutbef or et hec oi l sar es t eamedand wat er was hedandpr i ort ot heopeni ngandst ar tofi ns pec t i onwor k . Thi smet hodi seff ec t i v ei fdepos i t si nt hec oi l ar es uc ht hatt heywi l l bes of t enedordi s sol v edbygasoi l . Wh ent u be sar ec ok e do rc o nt a i nha r dde po s i t ,o t h erme t h od sma ybeus e d,s u c ha ss t e am a i rd ec o k i n g an dmec hani c al c l ea ni ngf orc ok edep os i t san dc hemi c al c l e ani ngf ors al tdepo si t s .Chemi c al c l eani ng an ds t eam ai rd ec ok i ngar epr ef er abl east he yt endt ocl e ant het ubet obar eme t al .Th ec hemi c al c l eani ngpr oc es sr equi r esci r c ul at i onofani nhi bi t edac i dt hr ought hec oi l unt i l al l depos i t shav ebeen s of t en edandr emo v ed.Thi si sus ual l yf ol l owedb ywat erwas hi ngt ofl us hal l d epos i t sf r om t hec oi l .St eam ai rde cok i n gpr oc es scons i s t soft heus es t eam,t hec oi l .St e am ai rde cok i ngpr oc es scons i s t soft heus e ofs t e am,a i ran dh ea tt or emo v et h ec ok e .Th eme ch ani c so fd ec ok i n ga r e : a.Shr i n ki n ga ndc r a ck i n gt h ec ok el o os eb yh ea t i n gt u be sf r om o ut s i d ewh i l es t e am b l owsc ok ef r o mt h e c oi l . b.Chemi c al r eac t i onofho tc ok ewi t hst eam. c .Chemi c al r eac t i onofc ok eando xy geni nai r . St eam an da i rs er v i c esar eper manent l yco nnec t edt ot h eheat er .Th eh eat erout l e tl i nei nc or por at esa s wi nge l bowwhi c h,d ur i ngt hed ec ok i ngo per at i on,i sdi s c onnec t edf r om t heo ut l e tl i neandc onn ec t edt o

t hed ec o ki ngh ea de r .Car emustbet akent oal l ow suffici entaccessandpl at f or mi ngwhent he swi ngel bowsar echangedover.Co k ei sc ar r i e db yt h i shea de rt ot h ed r u mo rs u mp . I ns o mei n st a nc esi tma yr e qu es t e db yt hePr oc es sDe par t men to rCl i e ntt h att h ed ec ok i n gman i f o l di s c onnec t edt oal l owf orr e v er s efl owdur i ngt h edec ok i n g.

%& Soot Blo#in I ns omeheat er st hec on v ec t i ons ec t i onc on t ai nst ub eswi t he xt ende ds ur f ac ei nt hef or m ofe i t herfi nsor s t uds .Ex t endedsur f ac et ubesar eus edt oi nc r eas et heconv ec t i onheatt r ans f erar eaatl owc api t al c os t . Be c au seoft h et e nd enc yofe x t e nde ds ur f ac et u be st of o ul wh enb ur ni n gh ea v yo i l s ,s o ot b l o wer sar e us ual l yi ns t al l ed. So ot bl ower sempl o yhi ghpr es s ur est eam t ocl ea nt het u beout ers ur f ac esofs ootandot herf or ei gn mat er i al .So ot bl o wer sma ybeei t heraut omat i cel ec t r i cmot orop er at edb yapus hb ut t onatgr ad e,or manual r equi r i ngoper at i onf r om apl at f or ml oc at edatt hecon vec t i onbankl ev el . Car emustbet aken t ha ts uffic i e ntc l e ar a nc ei sal l owe df ort hewi t hdr a wa lofs oot bl owe r s . Gener al l yheat er sar es uppl i edwi t hs oot bl owi ngf ac i l i t i esi nt hec onv ec t i ons ec t i onal t hought ubesma y no tbeoft heex t endedsur f ac et y pe.

% Instru$ents %1 Stac! a.Damper :Mec hani c al orpn eumat i c al l yoper at edt oc ont r ol t hedr af tt hr o ught hes t ac k . b.Dr af tg au ge( Pan dI ) c .Fl uet emper at ur e( TI ) d.Or s at( O2  COCO2  anal y zer ) . I ns t r ume nt sb. ,c .andd.ar eus edt oa cc es st hec or r ec tc ombus t i onc ondi t i ons .St eam i ssuppl i e df ort he Or s atc onnec t i oni nt hes t ac k.Wat eri ss uppl i edt ot heO 2  anal y zer .Pl at f or mi ngf ort heac c es st ot he s t ac ki ns t r ument si ssuppl i edwi t ht heheat er .

%& Heater Body a.Sk i nt her moc oupl esort ubewal l TI ’ s :t oi ndi c at eo ver heat i ngoft ubes . b.PI ’ s :t omeas ur et hedr af tpr es s ur et hr ought hecombus t i ons ec t i onoft heheat er .

Fi gur e s1 1 1i nc l .

Fi gur e1 .BOXTYPEHEATER PLAN

Fi gur e2 .PROCESSPI PI NG BOXHEATHER

Fi gur e3.VERTI CALHEATERWI THRADI ANTCONVECTI ONSECTI ON

Fi gur e4. VERTI CALHEATER WI THRADI ANTSECTI ON

Fi gur e5.Pl a nPr oc es sPi pi nga tVe r t i c alHe at e r

Fi gur e6. SNUFFI NG STEAM STATI ON

Fi gur e7 .

Fi gur e8 .

Fi gur e9.Na t ur a lDr a f tBur ne rF orFue lOi l /Fue lGa s

Fi gur e1 0

Fi gur e1 1 DECOKI NG PROCEDURE AFTERTUBESBECOMEHEADED,STEAM I SI NJECTEDATCONVECTI ONI NLETS,VALVES“1” , “ 2” ,“ 4”&“ 5”ARECLOSED“ 3”I SOPEN. TOSTARTBURNI NG,STEAM FLOW I SREDUCED.AI RI SI NTRODUCEDBYOPENI NG VALVE“ 4” . FORREVERSEFLOW,VAL VES“ 2” ,“ 3” ,“ 4”&“ 6”ARECLOSED,“ 1” &“ 5”AREOPEN.VALVE“2 ” I SOPENEDONL YI FREVERSEBURNI NG I SREQUI RED.WHI LEPASS“1 ”I SBEI NG DECOKED,