BOILER CONSTRUCTION Information Sheet Number 62B-203
INTRODUCTION The D-tye boi!er ha" been in"ta!!e# in U$S$ Na%y "hi" "in&e '()0$ *hether 600 "i or '200 "i+ D-tye boi!er &on"tru&tion i" ba"i&a!!y the "ame ,ith a fe, e&etion"+ "u&h a" number of fue! oi! burner" an# o%era!! o%e ra!! "i.e an# %o!ume$ RE/ERENCES a1 Boi!er" NST Chater 22' b1 /ireman N4EDTR '0)20 Serie" &1 Boi!er Te&hni&ian 352 N4EDTR '0)3)B #1 rin&i!e" of Na%a! En7ineerin7 '0899 : e1 Boi!er Oeration an# aintenan&e anua! N4SE N4SE 0()'-L-02260'0 IN/ORTION $ ain rou!"ion rou!"ion boi!er" boi!er" ro%i#e ro%i#e "team to the main main rou!"ion rou!"ion turbine" turbine" an# aui!iary "er%i&e" in or#er to "u!y a!! "hiboar# "team "y"tem" in a&&or#an&e ,ith #eman#$ refer to /i7ure '1$ It i" #e"i7nate# a " a D-tye boi!er be&au"e of the re!ati%e o"ition" of the #rum" an# "i#e hea#er ,hi&h form the !etter D$ !! Dtye boi!er" are #e"i7nate# a" un&ontro!!e# "uerheat boi!er" be&au"e a!! the "team 7enerate# by the boi!er mu"t a"" throu7h the "uerheater$ Suerheater out!et temerature i" a re"u!t of the &ombu"tion 7a" f!o, in roortion to the tota! amount of "team f!o, throu7h a!! ran7e" 0 - '20;1$ The #e"i7n &hara&teri"ti&" en"ure that the temerature ,i!! "tabi!i.e at "et oint$ The #e7ree o f "uerheat i" &a!&u!ate# by "ubtra&tin7 "team #rum temerature from the a&tua! rea#in7 on the "uerheater out!et temerature 7a7e$ In thi" !e""on ,e ,i!! eamine the &omonent" of the boi!er an# then ,e ,i!! brin7 e%erythin7 to7ether by #e"&ribin7 ho, ,ater an# "team i" 7enerate# an# a n# &ir&u!ate# throu7h the boi!er$ The f!o, ath of &ombu"tion 7a"e" throu7h the boi!er ,i!! a!"o be #i"&u""e#$
D T<E BOILER
/i7ure '
B$ The e&onomi.er i" a mu!ti-a"" heat e&han7er !o&ate# abo%e the main 7eneratin7 ban= at the ba"e of the ehau"t "ta&=+ "o that &ombu"tion 7a" ,i!! 7i%e u a !ot of it" remainin7 heat to the in&omin7 fee#,ater before a""in7 out the "ta&= Refer to /i7ure 21 The in&omin7 fee#,ater ab"orb" about '00 -200 / "en"ib!e heat from the ehau"t 7a"e"$ /in" are in"ta!!e# on the e&onomi.er tube" to in&rea"e the heatin7 "urfa&e area further+ he!in7 to in&rea"e effi&ien&y$
ECONOI>ER
/i7ure 2
C$ The "team #rum i" !o&ate# at the to of the boi!er to ro%i#e an uer re"er%oir for the ,ater &o%erin7 the 7eneratin7 tube ban=$ *ater i" #i"tribute# from the "team #rum to the !o,er #rum" an# hea#er" by ie" &a!!e# #o,n&omer"$ ?enerate# "team i" a!"o &o!!e&te# an# i" "earate# from the ,ater in the "team #rum$ Boi!er" are a!"o e@uie# ,ith "afety %a!%e" to re!ie%e e&e""i%e re""ure$ The %a!%e" are !o&ate# on the "team #rum an# "uerheater out!et$ They are #e"i7ne# to re!ie%e "uffi&ient re""ure to "afe!y "team the boi!er at '20; ,ith boi!er "team "to %a!%e" &!o"e# refer to /i7ure 31$ The"e %a!%e" are #i"&u""e# in #etai! in !e""on 62B-206$
D$ ir %ent" or air &o&=" are in"ta!!e# on to of the "team #rum to ee! air from in"i#e the "team #rum #urin7 &o!# boi!er !i7ht-off or ,hen fi!!in7 the boi!er$ The air %ent" or air &o&=" are "hut ,hen the boi!er "tart" 7eneratin7 "team$
S/ET< 4L4E CON/I?URTION
/i7ure 3
E$ The interna! fittin7" in the "team #rum he! #i"tribute the ,ater e%en!y throu7hout the #rum+ "earate the 7enerate# "team from the ,ater an# remo%e moi"ture from the "team before it !ea%e" the boi!er refer to /i7ure A1$ '$ Lo,er baff!e !ate" or aron !ate" Searate the in&omin7 fee#,ater an# 7enerate# "team an# #ire&t the "team to the "earator"$ 2$ rimary "earator" &y&!one "earator"1 Searate mo"t of the ,ater from the "team by 7i%in7 it a &y&!one or rotary motion "o that the ,ater arti&!e" are ee!!e# from the "team by the &entrifu7a! for&e"$ The"e "earator" are %erti&a!!y mounte# in the "team #rum "o that the "team ri"e" out the to an# the ,ater fa!!" ba&= into the "team #rum$ 3$ Se&on#ary "earator" &he%ron #ryer"1 Remo%e a##itiona! moi"ture from the "team by &han7in7 the #ire&tion of "team f!o, "e%era! time"$ The "team a""e" on but the moi"ture &annot ma=e the #ire&tion &han7e ,ith the "team$ The"e "earator" are mounte# abo%e the rimary "earator" an# #ire&t "team to the #ry bo ,hi&h &o!!e&t" the "team at the to of the "team #rum+ #ire&tin7 it to the "team out!et iin7 to the "uerheater$ A$ /ee#,ater !ea%e" the e&onomi.er an# enter" the boi!er throu7h the interna! fee# ie an# be&ome" boi!er ,ater$ erforation" a!on7 the "i#e of the fee# ie a!!o, ,ater to be #i"tribute# e%en!y throu7hout the "team #rum refer to /i7ure A1
STE DRU INTERNLS
/i7ure A
)$ Sin&e "u"en#e# "o!i#" may a&&umu!ate on the "urfa&e of the ,ater in the "team #rum+ there mu"t be mean" of remo%in7 them$ The "urfa&e b!o, ie i" u"e# to remo%e the"e !i7ht "u"en#e# "o!i#" from the "urfa&e of the ,ater an# to re#u&e the tota! #i""o!%e# "o!i# &ontent of the boi!er ,ater$ Su"en#e# "o!i#" u"ua!!y &on"i"t of oi!+ "a!t &ontaminant"+ or e&e""i%e treatment &hemi&a!" ,hi&h &an &au"e foamin7 on the ,ater "urfa&e$ Di""o!%e# "o!i#" u"ua!!y &on"i"t of "a!t &ontaminant" an# treatment &hemi&a!" that are in "o!ution$ /$ The D-tye boi!er u"e" the rin&i!e of a&&e!erate# natura! &ir&u!ation to &ir&u!ate ,ater throu7h the boi!er$ To enab!e thi" rin&i!e to ,or=+ re!ati%e!y &oo! ,ater ,i!! natura!!y &ir&u!ate throu7h !ar7e #iameter ie" to #i"tribution oint" !o, in the boi!er$ The #o,n&omer" are the"e !ar7e #iameter ie" &onne&tin7 the "team #rum ,ith the ,ater #rum an# !o,er hea#er" to en"ure roer &ir&u!ation by #e!i%erin7 ,ater from the "team #rum to the ,ater #rum an# !o,er hea#er"$ The #o,n&omer" are !o&ate# bet,een the inner an# outer air &a"in7 to rote&t them from the #ire&t ra#iant heat of the furna&e$ ?$ The ,ater #rum i" !o&ate# at the bottom of the boi!er be!o, the main 7eneratin7 ban= an# a&t" a" a !o,er re"er%oir of ,ater for #i"tribution to the main 7eneratin7 ban=$ !"o+ thi" !ar7e #rum "er%e" a" a &o!!e&tion oint for "o!i#" "!u#7e1 that re&iitate to the bottom that are remo%e# by bottom b!o,#o,n$ :$ The "i#e,a!! hea#er i" !o&ate# a!on7 the furna&e "i#e,a!! &onne&tin7 "i#e,a!! tube" from the furna&e f!oor to the "team #rum$ It #i"tribute" ,ater to the "i#e,a!! tube" an# ro%i#e" another b!o,#o,n oint for "!u#7e remo%a!$ The "i#e,a!! tube" are t,o in&h tube" ,hi&h rote&t the boi!er "i#e,a!! refra&tory from the #ire&t heat of &ombu"tion an# 7enerate a "ma!! amount of "team$ I$ The !o,er rear,a!! hea#er i" !o&ate# a!on7 the furna&e rear,a!! from the furna&e f!oor to the "team #rum or uer hea#er to ro%i#e a !o,er un&tion for rear,a!! tube"$ It #i"tribute" ,ater to the rear,a!! tube" an# ro%i#e" yet another b!o,#o,n oint for remo%a! of "!u#7e$ The rear,a!! tube" are t,o in&h tube" ,hi&h rote&t the boi!er rear,a!! refra&tory from the heat of &o mbu"tion an# 7enerate "ome "team$ NOTE By u"in7 ,a!! tube"+ more of the heat in the furna&e i" ab"orbe# by ,ater an# !e"" refra&tory materia! i" re@uire#+ thereby in&rea"in7 boi!er effi&ien&y an# re#u&in7 the boi!er ,ei7ht$ $ The uer rear,a!! hea#er i" often &a!!e# the f!oatin7 hea#er be&au"e of it" free"tan#in7 #e"i7n$ It i" !o&ate# a!on7 the rear,a!! of the furna&e roof to ro%i#e an uer un&tion for the rear,a!! tube"$ It &o!!e&t" the "team 7enerate# in the rear,a!! tube" an# #ire&t it to the "team #rum throu7h ri"er tube"$ F$ Ri"er tube" are !ar7e tube" !o&ate# abo%e the furna&e roof to ro%i#e a &onne&tion bet,een the uer rear,a!! hea#er an# the "team #rum$
L$ Suerheater "&reen,a!! tube" he! rote&t the "uerheater from #ire&t ra#iant heat of the furna&e$ The "&reen tube" &on"i"t of t,o to three "ta77ere# ro," of t,o in&h tube" ,hi&h are u"ua!!y &onne&te# from the "team #rum to the ,ater #rum$ Some boi!er" ha%e a "&reen,a!! hea#er in"ta!!e# ara!!e! to the "uerheater a!on7 the furna&e f!oor a" a !o,er &onne&tion an# a b!o,#o,n oint for "!u#7e$ $ The "team a""e" throu7h the "uerheater i&=in7 u "en"ib!e heat about 300A00 /1 ,hi&h in&rea"e" the ener7y of the "team+ a!!o,in7 it to erform more ,or=$ The "uerheater i" &omo"e# of "uerheater hea#er" ,hi&h #i"tribute "team to the "uerheater tube" or e!ement" an# #ire&t it from the in!et to out!et iin7$ The"e hea#er" an# e!ement" &an be either %erti&a!!y or hori.onta!!y mounte#$ Refer to /i7ure )1$
SUER:ETER
/i7ure )
N$ The bu!= of the "team 7enerate# by the boi!er i" forme# in the main 7eneratin7 ban= be&au"e it ha" the !ar7e"t heatin7 "urfa&e$ Thi" i" a !ar7e 7rou of one in&h tube" ,hi&h run from the ,ater #rum to the "team #rum an# are !o&ate# behin# the "uerheater$ O$ Sin&e the"e boi!er" are un&ontro!!e# "uerheat an# the !ant i" #e"i7ne# to u"e !o,er temerature "team in many a!i&ation" to he! re#u&e &on"tru&tion an# maintenan&e &o"t"+ the "team nee#e# for the"e "er%i&e" mu"t a"" throu7h a #e"uerheater$ The #e"uerheater i" a mu!ti-a"" tube bun#!e ,hi&h i" !o&ate# in the ,ater #rum in mo"t boi!er"$ There are "e%era! boi!er" ,hi&h ha%e the #e"uerheater in the "team #rum$ " the "uerheate# "team a""e" throu7h the tube bun#!e+ it 7i%e" u heat to the boi!er ,ater in the ,ater #rum$ $ The boi!er i" rote&te# from the hi7h temerature" of &ombu"tion by the refra&tory$ Refra&tory !ine" the in"i#e "urfa&e of the inner &a"in7 en&!o"in7 a!! of the furna&e area an# eten#in7 to the outer ro, of 7eneratin7 tube"$ There are "e%era! #ifferent tye" of refra&tory ,hi&h ,or= to7ether to rote&t the boi!er$ '$ /irebri&= i" a hea%y &a"te# refra&tory u"e# a" the outer !ayer of refra&tory an# i" eo"e# to the #ire&t f!ame" of &ombu"tion$ It ha" oor in"u!atin7 @ua!itie"+ but it ,i!! ,ith"tan# #ire&t f!ame &onta&t$
2$ In"u!atin7 bri&= i" a !i7ht,ei7ht &a"te# refra&tory u"e# bet,een the in"u!atin7 b!o&= an# firebri&=$ It ha" 7oo# in"u!atin7 roertie"+ but it ,i!! not ,ith"tan# #ire&t &onta&t ,ith f!ame$ 3$ In"u!atin7 b!o&= i" a re""e# fiber materia! u"e# net to the inner &a"in7$ It ha" the hi7he"t in"u!atin7 roertie" of the %ariou" refra&tory+ but it ,i!! not ,ith"tan# #ire&t &onta&t ,ith f!ame$ A$ Burner ti!e" are reforme# refra&tory u"e# to form burner &one" aroun# ,here the burner a""emb!y rotru#e" into the furna&e$ Burner ti!e" are a "e&ia!!y "hae#+ hea%y &a"te# refra&tory u"e# net to the in"u!atin7 bri&= aroun# the burner oenin7"$ They ha%e oor in"u!atin7 @ua!itie"+ but they ,i!! ,ith"tan# #ire&t f!ame &onta&t$ )$ :i7h temerature &a"tab!e refra&tory i" u"e# to fi!! in 7a" in refra&tory or ,here "hain7 i" nee#e# to &o%er irre7u!ar "hae# item"$ It i" u"e# to at&h refra&tory or to "mooth une%en area" bet,een bri&=,or=$ It i" a&=a7e# #ry an# mu"t be mie# ,ith ,ater rior to u"e+ %ery mu&h !i=e &ement or !a"ter$ 6$ Baff!e ti!e" are a "e&ia!!y "hae# refra&tory ma#e of "i!i&on &arbi#e for u"e in "ome boi!er" to form baff!e" on "uerheater "&reen tube"$ The"e baff!e" #ire&t the f!o, of &ombu"tion 7a"e" a&ro"" the "uerheater to he! maintain the temerature ,ithin #e"i7n arameter"$ 8$ *hen the refra&tory i" in"ta!!e# an# "ta&=e#+ it mu"t be he!# in !a&e$ n&hor bo!t" are u"e# for reforme# refra&tory$ The an&hor bo!t" are &onne&te# to the inner &a"in7 to "uort an# retain the refra&torie" in o"ition$ 9$ Sin&e the boi!er ean#" an# &ontra&t" ,ith heatin7 an# &oo!in7+ ean"ion oint" are bui!t into the refra&tory to a!!o, for the therma! ean"ion an# &ontra&tion$ G$ Sin&e the boi!er ean#" an# &ontra&t" a" it heat" u an# &oo!" #o,n+ "!i#in7 feet are in"ta!!e# to a!!o, the boi!er to mo%e ea"i!y$ The feet are !o&ate# be!o, the boi!er+ u"ua!!y un#er the front en# of the "i#e,a!! hea#er an# ,ater #rum$ There i" a 7rea"e# ho"hor-bron.e fri&tion !ate on ,hi&h the"e feet ,i!! mo%e$ The !anne# maintenan&e "y"tem S1 re@uire" !ubri&atin7 the "!i#in7 feet e%ery month$ Some ne,er "hi" ha%e erma!ube "!i#in7 feet ,hi&h ne%er re@uire !ubri&ation$ /ai!ure of the "!i#in7 feet to mo%e &an &au"e &ra&=" in the air &a"in7 an# &an &au"e hea#er han#ho!e !u7 !ea="$ o%ement in#i&ator" are in"ta!!e# on the "!i#in7 feet ,hi&h ha%e to be &he&=e# rior to !i7ht off+ #urin7 ,arm u+ an # after the boi!er i" on !ine to en"ure o"iti%e mo%ement of the "!i#in7 feet$ Ea&h time "!i#in7 feet are &he&=e# the re"u!t" "hou!# be !o77e# in the fireroom oeratin7 !o7$ Refer to fi7ure 61 SLIDIN? /EET CON/I?URTION
/i7ure 6 R$ The boi!er i" en&!o"e# by &a"in7" ,hi&h ro%i#e an airti7ht boun#ary from the boi!er furna&e u throu7h to the "ta&= area$ The inner &a"in7 en&!o"e" the boi!er fire"i#e area to the ba"e of "ta&= to ro%i#e an airti7ht !inin7 bet,een the &ombu"tion air "a&e an# furna&e to &ontain the ro#u&t" of &ombu"tion ,ithin the boi!er an# "uort the refra&tory materia!"$ The outer &a"in7 en&!o"e" the entire boi!er from the bi!7e to the "ta&= to ro%i#e #oub!e en&a"ement "o the boi!er air re""ure i" not affe&te# by the fireroom atmo"here$ The &ombu"tion air f!o," throu7h thi" "a&e bet,een the inner an# outer &a"in7 an# i" #ire&te# to the air re7i"ter"$ The "ta&= i" !o&ate# abo%e the boi!er e&onomi.er an# eten#" to abo%e the "uer"tru&ture to &arry boi!er &ombu"tion ro#u&t" "afe!y a,ay from the "hi$ The inner "ta&= or "mo=e ie ro%i#e" a ath for &ombu"tion 7a"e" to the atmo"here+ the outer "ta&= "uort" the inner "ta&= an # ro%i#e" a "a&e to re&ei%e in&omin7 &ombu"tion air to the boi!er an # rote&t" er"onne! from the hot inner "ta&= "urfa&e"$ S$ The fireroom ,at&h team mu"t be ab!e to monitor the ehau"t 7a"e" to he! maintain a &!ear "mo=e free "ta&=$ Smo=e in#i&ator" an# eri"&oe" are in"ta!!e# to a!!o, monitorin7 of the "ta&= 7a"e" !ea%in7 the boi!er$ The "mo=e in#i&ator i" an e!e&tro-me&hani&a! #e%i&e an# the eri"&oe i" an oti&a! #e%i&e$ !! "hi" ha%e eri"&oe" an# many ha%e e!e&tro-me&hani&a! "mo=e in#i&ator" or "ta&= 7a" ana!y.er"$ The"e #e%i&e" are !o&ate# abo%e the e&onomi.er at the ba"e of the "ta&= "o that &ombu"tion 7a"e" !ea%in7 the boi!er mu"t a"" throu7h it" !ine of "i7ht or
the "en"in7 e!ement$ /rom monitorin7 the "ta&= 7a"e"+ the &ombu"tion ro&e"" &an be a#u"te# for maimum effi&ien&y or a &a"ua!ty "ituation &an be #ete&te# Refer to /i7ure 81 T<ICL ERISCOE CON/I?URTION
/i7ure 8 T$ aintainin7 roer boi!er ,ater !e%e! i" one of the mo"t &riti&a! a"e&t" of boi!er oeration$ To be ab!e to monitor thi" &riti&a! arameter ,ater !e%e! in#i&ator" are in"ta!!e#$ There are t,o tye"+ a #ire&t rea#in7 7a7e 7!a"" mounte# on the "team #rum an# a remote ,ater !e%e! in#i&ator$ The 7a7e 7!a"" 7i%e" a #ire&t mea"urement of the "team #rum ,ater !e%e!$ The remote ,ater !e%e! in#i&ator 7i%e" an inferentia! in#i&ation of the "team #rum ,ater !e%e!$ '$ The #ire&t rea#in7 7a7e 7!a"" may be i"o!ate# or remo%e# for maintenan&e if ne&e""ary but+ at !ea"t t,o remote ,ater !e%e! in#i&ator" mu"t be in"ta!!e# an# ,or=in7$ Refer to /i7ure 91$
REOTE *TER LE4EL INDICTOR
/i7ure 9 2$ There are u"ua!!y t,o remote ,ater !e%e! in#i&ator" in the fireroom for ea&h boi!er$ They are !o&ate# on the !o,er !e%e! an# the BTO*H&on"o!e "tation$ There i" a!"o a remote in#i&ator !o&ate# at the thrott!e "tation for the en7ine "er%e# by that boi!er$ 3$ There are hi7h an# !o, ,ater a!arm" in"ta!!e# in the remote ,ater !e%e! in#i&ator"$ They are "et to a!arm ,hen the "team #rum ,ater !e%e! rea&he" 8 in&he" abo%e norma! or 6 be!o, norma! in&he" on mo"t "team "hi"$ U$ Be&au"e air &a"in7 fire" "ometime" o&&ur in the boi!er+ a "team "motherin7 "y"tem i" in"ta!!e# bet,een the inner an# outer &a"in7"$ Thi" iin7 &ome" from the ')0 "i #e"uerheate# "team "y"tem an# i" erforate# to a!!o, the "team to fi!! the &a"in7 an# "mother the fire$ The iin7 i" !o&ate# at the !o,er ortion of the &a"in7 un#er the furna&e f!oor an#Hor bri&=an$ Steam &an be a#mitte# to the furnan&e by fi!!in7 the air &a"in7 an# then oenin7 the air re7i"ter"$ Refer to fi7ure (1$ STE SOT:ERIN? CON/I?URTION
/i7ure ( 4$ On&e the "team f!o,in7 throu7h the "uerheater i" ,hat =ee" it from o%erheatin7+ there mu"t be a mean" of ro%i#in7 a f!o, rior to any "team re""ure for&in7 a f!o,$ Thi" mean" i" &a!!e# the "uerheater rote&tion "team "y"tem$ The in!et i" &onne&te# to the "team #rum "team out!et iin7 an# out!et i" &onne&te# to the #e"uerheater out!et iin7$ Thi" arran7ement ro%i#e" "team f!o, throu7h the "uerheater #urin7 !i7ht-off an# "e&urin7$ It i" a!"o the entry oint for the "team u"e# to ro%i#e a "team b!an=et !ay-u$ The "team b!e# off the boi!er to ro%i#e the f!o, i" route# to the aui!iary ehau"t "y"tem$ *hen the boi!er i" bein7 "e&ure#+ thi" "y"tem nee#" to be a!i7ne# to re%ent o%er re""uri.ation of the boi!er be&au"e it i" "ti!! 7eneratin7 "team$ Thi" "y"tem i" &ommon!y &a!!e# the "uerheater b!ee#er$ Refer to fi7ure '01 SUER:ETER ROTECTION S
/i7ure '0 *$ /ue! oi! burner" are !o&ate# on the boi!er front an# eten# into the furna&e to ro%i#e a mean" of firin7 the boi!er$ Deen#in7 on boi!er #e"i7n t,o to "i burner" are in"ta!!e# in the boi!er$ Refer to /i7ure ''1$ BURNER SSEBL<
/i7ure '' '$ The burner" #e!i%er fue! an# air to the boi!er furna&e in the roer miture to obtain otimum &ombu"tion$ The t,o main &omonent" of an oi! burner are the atomi.er a""emb!y an# the air re7i"ter a""emb!y$ The atomi.er #i%i#e" the fue! oi! into %ery fine arti&!e"+ the air re7i"ter a#mit" &ombu"tion air to the furna&e an# romote" miin7 of the air an# the fue! oi! "ray$ 2$ The tye" of atomi.er" u"e# on "hi" are "trai7ht me&hani&a!+ "team+ an# %ente# !un7er+ a" #e"&ribe# be!o,$ 3$ In "trai7ht me&hani&a! atomi.ation+ a!! the oi! ume# to the atomi.er i" "raye# into the furna&e$ The firin7 rate of thi" tye of burner i" &ontro!!e# by %aryin7 the "u!y fue! oi! re""ure an# &han7in7 "rayer !ate "i.e"$
A$ In "team atomi.ation+ "team i" u"e# to he! atomi.e the oi! into minute arti&!e" an# to roe&t a &one-"hae# "ray of atomi.e# oi! into the furna&e$ )$ The %ente# !un7er tye atomi.er i" #e"i7ne# to ermit a ,i#e ran7e of oeration u"in7 the "trai7ht me&hani&a! re""ure atomi.ation rin&i!e ,ithout the nee# to &han7e "rayer !ate "i.e" or u"e "team atomi.ation$ It i" foun# in '200 "i boi!er"$ $ Be&au"e the &ombu"tion 7a"e" !ea%e a"h or "oot #eo"it" on the tube "urfa&e" ,hi&h inhibit effi&ient heat tran"fer+ the "oot mu"t be remo%e#$ Soot b!o,er" u"e "team to b!o, "oot off of the tube "urfa&e"$ In a##ition to a&tin7 a" an in"u!ator+ thi" "oot form" "u!furi& a&i# ,hen it be&ome" ,et an# e%entua!!y &orro#e" the tube meta!$ '$ Boi!er" ha%e %aryin7 number" of "oot b!o,er" but+ there are t,o ba"i& tye"+ rotary an# "tationary$ They u"e unre#u&e# #e"uerheate# "team a" the moti%e for&e ,hi&h i" re#u&e# in the e!ement by an orifi&e to 300 "i for rotatin7 unit" an# aroimate!y ')0 "i for "tationary unit"$ U"in7 re!ati%e!y hot "team at a re#u&e# re""ure minimi.e" moi"ture in the "team ,hi&h &an !ea# to ero"ion or a&i# &orro"ion$ 2$ The rotary tye of "oot b!o,er ha" mu!ti-no..!e e!ement"$ The "oot b!o,er hea# "team %a!%e i" a&tuate# by a &am ,hen the e!ement i" rotate#$ The e!ement &an be turne# by a &ran=+ &hain+ or an air or e!e&tri& motor$ Steam i" a#mitte# from the hea# into an e!ement ,hi&h in&ororate" uniform!y "a&e# no..!e"Hho!e" to e%en!y #i"tribute "team a!on7 the area &o%ere#$ Refer to fi7ure '21
ROTR< SOOT BLO*ER
/i7ure '2 3$ The "tationary tye of "oot b!o,er u"ua!!y ha" one or t,o ro," of no..!e" #ire&te# to the area imme#iate!y near the #rum" of the boi!er$ Steam i" a#mitte# for a "hort #uration by a manua!!y or o,er a&tuate# "to %a!%e$
A$ The "oot b!o,er e!ement mu"t be =et &oo! an# &!ean #urin7 oeration$ To a&&om!i"h thi"+ a "ma!! amount of air i" ie# into the e!ement throu7h a "ma!! air !ine$ Thi" air i" &a!!e# "&a%en7in7 air an# &ome" from the &ombu"tion air that re""uri.e" the boi!er air &a"in7$ Thi" a!!o," a "ma!! amount of air to enter the "oot b!o,er e!ement to =ee it &oo! an# &!ean$ There i" a &he&= %a!%e in"ta!!e# in thi" !ine to re%ent "team from enterin7 the air &a"in7 #urin7 "oot b!o,er oeration$ )$ The oeration of "oot b!o,er" i" &a!!e# b!o,in7 tube"$ Tube" are b!o,n on the fo!!o,in7 minimum o&&a"ion" a$ fter !ea%in7 ort b$ Before enterin7 ort &$ fter ma=in7 hea%y "mo=e #$ On&e ea&h ,ee= ,hen "teamin7 NOTE EOSS re@uire" tube" to be b!o,n rior to "e&urin7 a boi!er+ if o""ib!e$ <$ Sin&e the boi!er ,ater &hemi"try &ontro! "y"tem"+ Che!ant or Coor#inate# ho"hate+ both "ett!e "!u#7e to he! maintain ,ater urity+ there mu"t ei"t a mean" to remo%e thi" "!u#7e$ The bottom b!o,#o,n "y"tem i" u"e# to remo%e "!u#7e from the ,ater #rum an# the !o,er hea#er"$ The "urfa&e b!o,#o,n "y"tem i" u"e# to remo%e "u"en#e# arti&!e" in the ,ater an# ro%i#e a mean" of &han7in7 out the ,ater in the boi!er to !o,er the &on#u&ti%ity an# #i""o!%e# "ub"tan&e"$ Both "y"tem" "hare a &ommon iin7 arran7ement ,ith an o%erboar# 7uar#in7 %a!%e an# o%erboar# #i"&har7e %a!%e$ Refer to fi7ure '31
SUR/CEHBOTTO BLO*DO*N IIN?
/i7ure '3 '$ Surfa&e b!o,#o,n" are &on#u&te# on a "teamin7 boi!er a" nee#e# to maintain boi!er ,ater ,ithin the roer &hemi&a! &ontro! !imit"$ The Che!ant "y"tem a!"o u"e" an o&&a"iona! "&um b!o, to maintain !imit"$
2$ boi!er i" bottom b!o,n on!y ,hen it i" "e&ure#$ Ne%er bottom b!o, a "teamin7 boi!er "in&e thi" &ou!# &au"e a !o"" of natura! &ir&u!ation an# boi!er #ama7e$ Boi!er" "ha!! be "e&ure# an# bottom b!o,n e%ery 360 "teamin7 hour" if the Che!ant treatment "y"tem i" in"ta!!e# or e%ery '69 if the Coor#inate# ho"hate CO:OS1 "y"tem i" in u"e$ There are many &on#ition" that re@uire a boi!er to be bottom b!o,n$ /or a &om!ete !i"tin7 refer to NST 22' or 220 %o!ume II$ $ Fno,in7 the ,aterH"team f!o, throu7h the boi!er i" &riti&a! to un#er"tan#in7 the interre!ation"hi" of the boi!er &omonent"$ "ummary fo!!o," '$ The f!o, be7in" ,hen fee#,ater enter" the e&onomi.er in!et hea#er an# f!o," throu7h the e&onomi.er tube" to the out!et hea#er i&=in7 u aroimate!y '00-200 / of "en"ib!e heat to about 3)0 /$ 2$ /ee#,ater !ea%in7 the e&onomi.er enter" the "team #rum %ia the interna! fee# ie$ The fee# ie #i"tribute" the ,ater e%en!y a!on7 the !en7th of the "team #rum$ 3$ Boi!er ,ater then f!o," o%er the baff!e !ate" to the en#" of the #rum ,here the &oo!er more #en"e ,ater f!o," #o,n throu7h the #o,n&omer" to the ,ater #rum an# !o,er hea#er"$ A$ *ater in the ,ater #rum an# !o,er hea#er" i" #i"tribute# to the %ariou" 7eneratin7 tube" to re!a&e the ,ater bein7 7enerate# into "team$ )$ " ,ater ri"e" throu7h the tube"+ it i" eo"e# to the &ombu"tion 7a"e" throu7h the tube ,a!!" in&rea"in7 the ,ater tem ,hi&h #e&rea"e itJ" #en"ity+ a!!o,in7 it to &ontinue the f!o, u,ar#$ 6$ Continuin7 u,ar#+ a ortion of the ,ater &han7e" to "team an# enter" the "team #rum un#er the baff!e !ate"$ The ,ater-"team miture i" 7ui#e# to the rimary "earator" ,hi&h "earate the e&e"" ,ater from the "team by &entrifu7a! motion$ Searate# ,ater fa!!" ba&= to the "team #rum abo%e the baff!e !ate"$ 8$ Steam eit" the rimary "earator an# enter" the "e&on#ary "earator" ,here the rai# &han7e" in #ire&tion of f!o, &au"e" it to 7i%e u more moi"ture$ oi"ture remo%e# #rain" ba&= to the "team #rum a bo%e the baff!e !ate"$ 9$ !! a&&umu!ate# "team i" #ire&te# to the #ry bo$ The @ua!ity of "aturate# "team !ea%in7 the "team #rum i" #e"i7ne# to be (($8); moi"ture free$ ($ Steam f!o," throu7h the "aturate# "team !ine to the "uerheater in!et hea#er$ It ma=e" four a""e" throu7h the "uerheater in&rea"in7 "team temerature 300-A00 / to aroimate!y 9)0 / an# then eit" throu7h the out!et hea#er$ '0$ Suerheate# "team !ea%e" the out!et hea#er an# a ortion i" route# to the #e"uerheater in!et ba"e# uon "y"tem #eman#$ !! remainin7 "team 7oe" throu7h the main "team "to to the main "team "y"tem to ro%i#e "uerheate# "team to the main en7ine turbine"+ "hiJ" "er%i&e turbine 7enerator" SST?1+ an# on "ome "hi"+ the main fee# um" /1$ ''$ The "team that a""e" throu7h the #e"uerheater ,hi&h i" "ubmer7e# in the ,ater #rum+ 7i%e" u "uerheat to the "urroun#in7 ,ater$ Steam
!ea%in7 the #e"uerheater a""e" throu7h the aui!iary "team "to to ro%i#e "team to a!! aui!iary "y"tem #eman#"$ '2$ "ummary of the &ombu"tion 7a" f!o, fo!!o," a$ Combu"tion 7a"e" f!o, from the furna&e throu7h the "&reen,a!! tube"+ "uerheater tube"+ main 7eneratin7 ban=+ an# e&onomi.er$ The hot &ombu"tion 7a"e" then a"" throu7h the inner "ta&= an# fina!!y eit the "ta&= to the atmo"here$ Refer to fi7ure '1
