78:
138:. External treatment of raw water supplies intended for use within a boiler is focused on the removal of impurities before they reach the boiler. Internal treatment within the boiler is focused on limiting the tendency of water to dissolve the boiler, and maintaining impurities in forms least likely to cause trouble before they can be removed from the boiler in boiler blowdown.
65:
294:
deposits. Acceptable phosphate concentrations decrease from 140 mg/L in low pressure boilers to less than 40 mg/L at pressures above 1,500 pounds per square inch (10,000 kPa). Recommended alkalinity similarly decreases from 700 mg/L to 200 mg/L over the same pressure range.
403:
and boilers generating steam for use in direct contact with contaminating materials may not recycle condensed steam. Replacement water is required to continue steam production. Make-up water is initially treated to remove floating and suspended materials. Hard water intended for low-pressure
344:
are added to control scale formation. Potential decomposition at high temperatures limits chelant use to boilers operating at pressures less than 1,500 pounds per square inch (10,000 kPa). Decomposition products may cause metal corrosion in areas of stress and high temperature.
195:
may be used to maintain reducing conditions within the boiler. Sulphite is less desirable in boilers operating at pressures above 1,000 pounds per square inch (6,900 kPa); because sulfates formed by combination with oxygen may form sulfate scale or decompose into corrosive
85:
Impurities in water will leave solid deposits as steam evaporates. These solid deposits thermally insulate heat exchange surfaces initially decreasing the rate of steam generation, and potentially causing boiler metals to reach failure temperatures.
200:
or hydrogen sulfide at elevated temperatures. Excess hydrazine may evaporate with steam to provide corrosion protection by neutralizing carbon dioxide in the steam condensate system; but it may also decompose into ammonia which will attack
261:
may be added to control crystal growth and disperse precipitates. The soft sludge of precipitates and organic materials accumulates in quiescent portions of the boiler to be removed during bottom blowdown.
180:
before it corrodes the boiler, to precipitate dissolved solids before they form scale on steam-generating surfaces, and to remove those precipitates from the vicinity of the steam-generating surfaces.
302:
under porous scale on steam generating surfaces within the boiler. High pressure boilers using demineralized water are most vulnerable to caustic corrosion. Hydrolysis of
90:
were not uncommon until surviving boiler operators learned how to periodically clean their boilers. Some solids could be removed by cooling the boiler so differential
126:
focused on the removal or chemical modification of substances potentially damaging to the boiler. Varying types of treatment are used at different locations to avoid
245:
treated this way causes a fairly high concentration of suspended solid particles within the boiler to serve as precipitation nuclei preventing later deposition of
106:. Various rates of boiler blowdown could reduce the frequency of cleaning, but efficient operation and maintenance of individual boilers was determined by
399:
All boilers lose some water in steam leaks; and some is intentionally wasted as boiler blowdown to remove impurities accumulating within the boiler.
176:
levels minimizing water solubility of boiler materials while allowing efficient action of other chemicals added to prevent foaming, to consume
832:
221:
Boilers operating at pressures less than 200 pounds per square inch (1,400 kPa) may use unsoftened feedwater with the addition of
17:
761:
529:
497:
322:
1002:
298:
Coordinated control of pH and phosphates attempts to limit caustic corrosion occurring from concentrations of
375:
is often used to convert condensate to feedwater by removing potentially damaging gases including oxygen,
391:
vessel) helps to maintain water purity, and in particular protect the boiler from a condenser tube leak.
945:
890:
123:
872:
915:
925:
448:
992:
135:
1068:
971:
966:
754:
360:
326:
103:
28:
45:, or in associated piping, pumps and other equipment, that is intended for evaporation into
862:
837:
169:
8:
935:
515:
303:
234:
895:
847:
518:
506:
307:
238:
127:
940:
900:
882:
867:
852:
809:
525:
493:
287:
230:
147:
91:
213:
may be preferred for corrosion protection of condensate systems with copper alloys.
1104:
1063:
976:
824:
794:
747:
400:
384:
354:
283:
271:
226:
222:
165:
98:
solids to crack and flake off metal boiler surfaces. Other solids were removed by
87:
54:
930:
920:
804:
428:
405:
368:
246:
188:
107:
58:
337:. Solubility of these complex ions may reduce blowdown requirements if anionic
270:
Boiler sludge concentrations created by coagulation treatment may be avoided by
1109:
1078:
1032:
842:
789:
376:
279:
197:
77:
1098:
1053:
950:
910:
857:
111:
1007:
997:
905:
814:
799:
436:
432:
388:
364:
299:
164:
exhibits different physical and chemical properties than those observed at
1083:
1037:
1017:
338:
153:
95:
274:
treatment when water hardness is less than 60 mg/L. With adequate
1027:
1022:
784:
427:
scale. High-pressure boilers typically require water demineralized by
291:
275:
242:
516:
Woodruff, Everett B.; Lammers, Herbert B.; Lammers, Thomas F. (1984).
420:
372:
334:
286:. Lignin may be processed for high temperature stability to control
192:
131:
50:
507:
Perry, Robert H.; Chilton, Cecil H.; Kirkpatrick, Sidney D. (1963).
278:, addition of sodium phosphate produces an insoluble precipitate of
1073:
1012:
413:
250:
157:
487:
460:
424:
380:
341:
330:
318:
258:
254:
210:
770:
416:
409:
202:
177:
64:
42:
206:
161:
46:
38:
99:
739:
367:
steam for re-use within the boiler. Steam condensate is
419:
of dissolved calcium and magnesium most likely to cause
295:
Foaming problems are more common with high alkalinity.
110:
until chemists devised means of measuring and adjusting
173:
517:
488:Linsley, Ray K. & Franzini, Joseph B. (1972).
461:Babbitt, Harold E. & Doland, James J. (1949).
57:, steam condensate being returned to a boiler, or
469:
1096:
478:
229:to maintain alkaline conditions to precipitate
755:
68:Storage tank of water for locomotive boilers.
359:Many large boilers including those used in
282:with magnesium hydroxide and magnesium and
762:
748:
472:Handbook of Industrial Water Conditioning
371:, but it may contain dissolved gases. A
117:
76:
63:
249:scale. Natural organic materials like
14:
1097:
657:
655:
172:. Chemicals may be added to maintain
743:
733:Woodruff, Lammers & Lammers p.527
697:Woodruff, Lammers & Lammers p.530
618:
616:
614:
612:
597:Woodruff, Lammers & Lammers p.516
53:intended for use in boilers, treated
183:
141:
122:Boiler water treatment is a type of
652:
306:is a pH buffer in equilibrium with
114:to minimize cleaning requirements.
49:. The term may also be applied to
24:
609:
474:(7th ed.). Betz Laboratories.
205:alloys. Products based on filming
25:
1121:
715:Linsley & Franzini pp.454-456
72:
394:
727:
718:
709:
700:
691:
682:
673:
664:
643:
634:
323:ethylenediaminetetraacetic acid
1003:Internally rifled boiler tubes
625:
600:
591:
582:
573:
564:
555:
546:
387:. Inclusion of a polisher (an
216:
13:
1:
539:
524:(5th ed.). McGraw-Hill.
329:(NTA) form complex ions with
265:
61:being removed from a boiler.
511:(4th ed.). McGraw-Hill.
509:Chemical Engineers' Handbook
348:
7:
769:
490:Water-Resources Engineering
442:
313:
10:
1126:
724:Babbitt & Doland p.388
470:Betz Laboratories (1976).
454:
352:
145:
124:industrial water treatment
26:
1046:
985:
959:
881:
823:
777:
661:Kemmer pp.39-13&39-16
649:Kemmer pp.39-13&39-15
479:Kemmer, Frank N. (1979).
588:Kemmer pp.39-13 to 39-17
481:The NALCO Water Handbook
463:Water Supply Engineering
579:Kemmer pp.39-1&39-5
449:Dealkalization of water
361:thermal power stations
310:and sodium hydroxide.
118:Boiler water treatment
82:
81:Boiler feed water pump
69:
18:Boiler water treatment
972:Electric water boiler
967:Electric steam boiler
520:Steam-Plant Operation
327:nitrilotriacetic acid
80:
67:
29:electric water boiler
891:Babcock & Wilcox
170:atmospheric pressure
27:For the device, see
304:trisodium phosphate
290:scale and magnetic
235:magnesium hydroxide
104:mechanical scouring
1047:Boiler peripherals
883:Water-tube boilers
670:Betz pp.90&104
308:disodium phosphate
239:magnesium silicate
83:
70:
1092:
1091:
986:Boiler components
825:Fire-tube boilers
401:Steam locomotives
288:calcium phosphate
284:calcium silicates
231:calcium carbonate
184:Oxygen scavengers
160:within a boiler,
148:Superheated water
142:Within the boiler
92:thermal expansion
88:Boiler explosions
16:(Redirected from
1117:
1064:Feedwater heater
977:Electrode boiler
960:Electric boilers
764:
757:
750:
741:
740:
734:
731:
725:
722:
716:
713:
707:
704:
698:
695:
689:
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680:
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671:
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598:
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580:
577:
571:
568:
562:
559:
553:
550:
535:
523:
512:
503:
484:
475:
466:
408:by substituting
385:hydrogen sulfide
355:Boiler feedwater
272:sodium phosphate
227:sodium hydroxide
223:sodium carbonate
166:room temperature
152:At the elevated
55:boiler feedwater
21:
1125:
1124:
1120:
1119:
1118:
1116:
1115:
1114:
1095:
1094:
1093:
1088:
1042:
981:
955:
877:
819:
773:
768:
738:
737:
732:
728:
723:
719:
714:
710:
705:
701:
696:
692:
687:
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669:
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621:
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601:
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592:
587:
583:
578:
574:
569:
565:
560:
556:
551:
547:
542:
532:
500:
492:. McGraw-Hill.
457:
445:
429:reverse osmosis
404:boilers may be
397:
369:distilled water
357:
351:
316:
268:
247:calcium sulfate
219:
189:Sodium sulphite
186:
150:
144:
120:
108:trial and error
94:caused brittle
75:
59:boiler blowdown
32:
23:
22:
15:
12:
11:
5:
1123:
1113:
1112:
1107:
1090:
1089:
1087:
1086:
1081:
1079:Snifting valve
1076:
1071:
1069:Feedwater pump
1066:
1061:
1056:
1050:
1048:
1044:
1043:
1041:
1040:
1035:
1033:Thermic siphon
1030:
1025:
1020:
1015:
1010:
1005:
1000:
995:
989:
987:
983:
982:
980:
979:
974:
969:
963:
961:
957:
956:
954:
953:
948:
943:
938:
933:
928:
923:
918:
913:
908:
903:
898:
893:
887:
885:
879:
878:
876:
875:
870:
865:
860:
855:
850:
845:
840:
835:
829:
827:
821:
820:
818:
817:
812:
807:
802:
797:
792:
787:
781:
779:
778:Simple boilers
775:
774:
767:
766:
759:
752:
744:
736:
735:
726:
717:
708:
699:
690:
681:
672:
663:
651:
642:
633:
631:Kemmer p.39-16
624:
608:
599:
590:
581:
572:
563:
554:
544:
543:
541:
538:
537:
536:
530:
513:
504:
498:
485:
483:. McGraw-Hill.
476:
467:
465:. McGraw-Hill.
456:
453:
452:
451:
444:
441:
396:
393:
377:carbon dioxide
353:Main article:
350:
347:
315:
312:
280:hydroxyapatite
267:
264:
218:
215:
198:sulfur dioxide
185:
182:
146:Main article:
143:
140:
119:
116:
74:
73:Early practice
71:
9:
6:
4:
3:
2:
1122:
1111:
1108:
1106:
1103:
1102:
1100:
1085:
1082:
1080:
1077:
1075:
1072:
1070:
1067:
1065:
1062:
1060:
1057:
1055:
1054:Air preheater
1052:
1051:
1049:
1045:
1039:
1036:
1034:
1031:
1029:
1026:
1024:
1021:
1019:
1016:
1014:
1011:
1009:
1006:
1004:
1001:
999:
996:
994:
991:
990:
988:
984:
978:
975:
973:
970:
968:
965:
964:
962:
958:
952:
949:
947:
944:
942:
939:
937:
934:
932:
929:
927:
924:
922:
919:
917:
914:
912:
909:
907:
904:
902:
899:
897:
894:
892:
889:
888:
886:
884:
880:
874:
871:
869:
866:
864:
861:
859:
856:
854:
851:
849:
846:
844:
841:
839:
838:Franco-Crosti
836:
834:
831:
830:
828:
826:
822:
816:
813:
811:
808:
806:
803:
801:
798:
796:
793:
791:
788:
786:
783:
782:
780:
776:
772:
765:
760:
758:
753:
751:
746:
745:
742:
730:
721:
712:
706:Kemmer p.39-5
703:
694:
688:Kemmer p.14-1
685:
676:
667:
658:
656:
646:
637:
628:
619:
617:
615:
613:
603:
594:
585:
576:
567:
558:
552:Kemmer p.39-2
549:
545:
533:
531:0-07-071732-X
527:
522:
521:
514:
510:
505:
501:
499:0-07-037959-9
495:
491:
486:
482:
477:
473:
468:
464:
459:
458:
450:
447:
446:
440:
438:
434:
430:
426:
422:
418:
415:
411:
407:
402:
395:Make-up water
392:
390:
386:
382:
378:
374:
370:
366:
362:
356:
346:
343:
340:
336:
332:
328:
324:
320:
311:
309:
305:
301:
300:hydroxyl ions
296:
293:
289:
285:
281:
277:
273:
263:
260:
256:
252:
248:
244:
240:
236:
232:
228:
224:
214:
212:
208:
204:
199:
194:
190:
181:
179:
175:
171:
167:
163:
159:
155:
149:
139:
137:
133:
129:
125:
115:
113:
112:water quality
109:
105:
101:
97:
93:
89:
79:
66:
62:
60:
56:
52:
48:
44:
40:
36:
30:
19:
1059:Boiler water
1058:
1008:Safety valve
998:Fusible plug
936:Thimble tube
729:
720:
711:
702:
693:
684:
675:
666:
645:
636:
627:
622:Perry p.9-51
602:
593:
584:
575:
570:Perry p.9-50
566:
557:
548:
519:
508:
489:
480:
471:
462:
437:ion-exchange
433:distillation
398:
389:Ion exchange
358:
317:
297:
269:
220:
187:
154:temperatures
151:
121:
84:
35:Boiler water
34:
33:
1084:Superheater
1038:Water gauge
896:Corner tube
339:carboxylate
217:Coagulation
102:washing or
96:crystalline
1099:Categories
1028:Steam drum
1023:Steam dome
941:Three-drum
901:Field-tube
868:Transverse
853:Locomotive
810:Lancashire
540:References
325:(EDTA) or
292:iron oxide
276:alkalinity
266:Phosphates
243:Hard water
37:is liquid
795:Egg-ended
679:Betz p.90
640:Betz p.99
606:Betz p.86
561:Betz p.95
421:carbonate
373:deaerator
365:condensed
349:Feedwater
335:magnesium
193:hydrazine
158:pressures
132:corrosion
51:raw water
41:within a
1074:Injector
1013:Smokebox
946:Vertical
931:Stirling
921:Sentinel
916:Monotube
873:Vertical
805:Haystack
443:See also
414:divalent
406:softened
363:recycle
342:polymers
319:Chelants
314:Chelants
251:starches
209:such as
1105:Boilers
993:Firebox
843:Haycock
833:Cochran
790:Cornish
771:Boilers
455:Sources
425:sulfate
417:cations
381:ammonia
331:calcium
259:lignins
255:tannins
211:Helamin
136:foaming
951:Yarrow
926:Spiral
911:LaMont
863:Scotch
858:Pistol
848:Launch
528:
496:
410:sodium
207:amines
203:copper
178:oxygen
43:boiler
1110:Water
906:Flash
815:Wagon
800:Flued
321:like
162:water
134:, or
128:scale
47:steam
39:water
1018:Stay
526:ISBN
494:ISBN
423:and
412:for
383:and
333:and
257:and
237:and
168:and
156:and
100:acid
785:Box
435:or
241:.
225:or
191:or
1101::
654:^
611:^
439:.
431:,
379:,
253:,
233:,
174:pH
130:,
763:e
756:t
749:v
534:.
502:.
31:.
20:)
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