ABSTRACT One of the reasons of the degradation of operational efficiency of fossil power plants is corrosion that takes place in the water-steam cycle during operation or downtime. Filming amine octadecylamine (ODA) is one of the chemicals used for reduction of corrosion rate of construction materials during downtime. This chemical not only reduces corrosion rate, but also helps to remove deposits. The data on the ODA effect on the efficiency of removal of deposits from heat exchange surfaces during equipment layup are presented. After ODA application a change in distribution of impurities along the height of deposits was found. In particular, chlorides move from the metal surface to the upper deposit layer, resulting in decrease of the corrosion rate. Results of field tests at cogeneration fossil power plant indicate that the use of ODA for the equipment layup reduced tube failures and deposition rate in district water heaters and hot water boilers

Andrei Ye Verkhovsky

Igor N Trofimov

Tamara I Petrova

Valery I Kashinsky

Yevgeny V Chernyshev

CiteSeerX

DownloaFORMATION OF PROTECTIVE FILMS OF OCTADECYLAMINE ON THE SURFACE 
OF CONSTRUCTION MATERIALS IN THE WATER-STEAM CYCLE AT FOSSIL 
POWER PLANTS 
 
 
 
 
Tamara I. Petrova 
Moscow Power Institute 
(Technical University) 
14 Krasnokazarmennaya 
Moscow, 111250, Russia 
petrova@twt.mpei.ac.ru
Valery I. Kashinsky 
Moscow Power Institute 
(Technical University) 
14 Krasnokazarmennaya 
Moscow, 111250, Russia 
KashinskyVI@mpei.ru 
Andrei Ye. Verkhovsky 
Moscow Power Institute 
(Technical University) 
14 Krasnokazarmennaya 
Moscow, 111250, Russia 
VerkhovskyAY@mpei.ru 
 
Yevgeny V. Chernyshev  
Mosenergo Power Plant 
5 Energetikov 
Dzerzhinsky, Moscow Region, 140091, Russia 
postman@twt.mpei.ac.ru 
Igor N. Trofimov  
Mosenergo Power Plant 
5 Energetikov 
Dzerzhinsky, Moscow Region, 140091, Russia 
PetrovaTI@mpei.ru 
 
Proceedings of ESDA2006 
8th Biennial ASME Conference on Engineering Systems Design and Analysis 
July 4-7, 2006, Torino, Italy 
 
 
ESDA2006-95237 
 
ABSTRACT 
One of the reasons of the degradation of operational 
efficiency of fossil power plants is corrosion that takes place in 
the water-steam cycle during operation or downtime. Filming 
amine octadecylamine (ODA) is one of the chemicals used for 
reduction of corrosion rate of construction materials during 
downtime. This chemical not only reduces corrosion rate, but 
also helps to remove deposits. The data on the ODA effect on 
the efficiency of removal of deposits from heat exchange 
surfaces during equipment layup are presented. After ODA 
application a change in distribution of impurities along the 
height of deposits was found. In particular, chlorides move 
from the metal surface to the upper deposit layer, resulting in 
decrease of the corrosion rate. Results of field tests at co-
generation fossil power plant indicate that the use of ODA for 
the equipment layup reduced tube failures and deposition rate 
in district water heaters and hot water boilers. 
 
INTRODUCTION 
 Some researchers state that corrosion and deposition in the 
water-steam cycle of fossil power plants are among basic 
reasons for increase in electricity and steam cost. The highest 
cost component is the cost of reimbursement for electricity and  
ded From: https://proceedings.asmedigitalcollection.asme.org on 06/29/2019 Terms of Ussteam losses, which now is up to 7,000 US$/MW (1, 2). Thus, 
measured aimed at reduction of corrosion and deposition are of 
paramount importance. 
FIELD WORK 
One of the causes for decrease in operational efficiency of  
co-generation power plants in Russia is corrosion in district 
water heaters No. 1 and 2 (DWH-1 and DWH-2) commonly 
used in Russia to heat up water for district heating system with 
steam extracted from turbine. These heaters are manufactured 
from 321H stainless steel. These corrosion problems have 
occurred at several power plants. Prior to 1994, the frequent 
shutdowns of the DWH-1 and DWH-2 took place with large 
number of tubes being blanked off due to their failures. In 1988 
and 1989 the DWH-2 tubes at 250 MW units were completely 
replaced, and two of these heaters went through the tube 
replacement again in 1995 and 1998. 
To find out the cause of tube failure, the condition of one 
of the tube cut from the DWH-2 was analyzed. The analysis 
showed that the tube had open cracks with predominant 
location at a distance of ca. 200 mm from the attachment with 
tube sheet at both sides (Fig. 1). Near these locations cavern-
type pits were found. The study of the tube surface revealed 
that all the cracks initiated from pits located on the outer tube 1 Copyright © 2006 by ASME 
e: http://www.asme.org/about-asme/terms-of-use
Downsurface. Cases of crack development on the inner tube surface 
were not found. 
 
 
Pitting corrosion of metal in this region developed under 
black-colored deposits of iron corrosion products; corrosion 
type – inter-crystalline cracking. 
Assuming that the fluid acts on the tube uniformly along 
the tube length, the crack initiation in metal should occur in 
locations of the maximum metal stress. This is confirmed by 
the analysis of condition of the tube surface. But steam entering 
the DHW can contain fine droplets of moisture with much 
higher levels of corrosive impurities – chloride and sulfate – 
than usually found in the bulk steam. Therefore, the crack 
initiation could be caused not only my mechanical stress in the 
tube, but also by elevated levels of corrosive impurities. 
A special sampling device was used for steam sampling at 
the DHW-1 and DHW-2 inlet; the chemical analysis of the 
samples showed that the chloride and sulfate concentrations at 
the inlet of these heaters were higher than in the turbine inlet 
steam (3). 
For reduction of the DHW corrosion rate during summer 
outage at Mosenergo co-generation power plant it was decided 
to perform layup of these heaters with filming amine 
octadecylamine (ODA). As a result, the DWH-2 tube failures 
markedly decreased. 
One of the advantages of the ODA use for layup of the 
steam side of the DWHs at 250 MW units was reduction of 
chloride content on the tube surface and decrease in failures of 
both heaters. One of the causes for the reduced failures consists 
of the presence of residual microfilm of ODA on the outer tube 
surface. This microfilm protects the tube against penetration of 
chloride into micro cracks. 
The positive experience was also obtained during layup 
with ODA of the inner surface of the DHW-1 at 100 MW units. 
In addition of the “washing-out” effect, the deposition rate was 
reduced and temperature drop stabilized for five-year period. 
After positive use of the layup with ODA on the DHWs, 
the peak hot water boilers were selected for use with this 
method. The operational problems of these boilers consisted of 
increased deposition rate, accumulation of deposits even during 
 
 
Figure 1. Region of Open Cracks of the DHW-2 Tube 
(1 – tube attachment with tube sheet; 2 – region of open 
cracks).  
loaded From: https://proceedings.asmedigitalcollection.asme.org on 06/29/2019 Terms of Uboiler outage with district water flow. After ODA use for the 
summer layup of heat exchange surfaces of the boiler, the 
additional effect of washing of deposits from the surface was 
observed. In addition, protective micro film of ODA on the 
surface reduced deposition rate during both operation and 
outage. Positive application of layup and washing at low level 
of deposits should increase operational period of hot water 
boilers and convective tube sections; in this case there is a 
possibility for an increase in service life of equipment. 
One of the major issues during use of ODA for layup of 
power-generating equipment is about stability of the ODA film 
formed on the metal surface at different conditions of the 
equipment operation. It is known that one of the advantages of 
the ODA use is the removal of chloride from the metal surface 
(4-6). Therefore, study of the ODA effect on distribution of 
impurities in deposition layer is of significant interest. 
Stability of the protective ODA film was evaluated with 
the data produced during the layup with ODA of the hot water 
boilers in 2001 prior to the summer outage. Tube specimens 
were cut from the boilers for determination of amount of 
deposits before and after the layup; in addition, the specific 
sorption of ODA on the tube surface after the layup was 
determined. The deposition and ODA film thicknesses were not 
measured. The data indicate that the amount of deposits in 
almost all boiler heat exchange sections after the layup 
decreased as compared to the condition before the layup (Table 
1, Boiler No. 8). 
The specific ODA sorption on the surfaces of the hot water 
boiler No. 8 was 0.592-12.837 μg/cm2, and that of the boiler 
No. 1 – 0.728-3.436 μg/cm2, i.e. it was much higher than 
theoretical value (0.0273 μg/cm2). 
For determination of stability of the ODA film on metal 
surface, one of the tube specimens cut from the waterwall of 
the boiler No. 1, washed in three times succession with water at 
temperature of 90-95 oC. Each washing lasted six hours with 
subsequent determination of the specific ODA sorption on the 
specimen surface and amount of deposits. Unfortunately, there 
was no deposition data for the boiler No. 1 before the layup, 
and it was not possible to compare amount of deposits before 
and after the layup. 
These data show that during short-term washing the 
specific ODA sorption on metal surface decreased, but even 
after the last washing it significantly exceeded theoretical 
value. 
After the end of the 2001-2002 heating season the layup of 
these two boilers was performed again, and during the 2002-
2003 heating season the boiler No. 1 was under operation for 
1,212 hours, and the boiler No. 8 – 2,662 hours.  After the end 
of the 2002-2003 heating season, the residual specific ODA 
sorption and amount of deposits were determined on the tube 
surfaces of these boilers. 
For the determination of the amount of ODA adsorbed on 
the metal surface, the specimen was put into the beaker filled 
with 50 ml of 1N acetic acid solution and was kept during 1.5 
hours at boiling aqueous bath conditions. After that the solution 2 Copyright © 2006 by ASME 
se: http://www.asme.org/about-asme/terms-of-use
was moved to separation funnel, and the beaker and the 
specimen were rinsed with demineralized water for at least 
three times; after each rinse the portion of used demineralized 
water was added to the separation funnel. The ODA 
concentration in the solution was performed with technique 
described in (8), the determination sensitivity was 100 ppb. 
This procedure was repeated until the ODA concentration 
in the solution was reduced down to 100 ppb. Results of all 
determinations of ODA concentration were summed up; the 
specific sorption was determined from the ODA amount 
removed from the specimen and related to the unit area. 
The results of the analysis show that after the 2002-2003 
heating season some amount of ODA that basically exceeded 
the theoretical one, still remained on the metal surface. 
For determination of the ODA effect on composition of 
deposits in both the surface layer and across it, the deposits  
 
Downloaded From: https://proceedings.asmedigitalcollection.asme.org on 06/29/2019 Terms of Usewere investigated after the layup and washing at temperature of 
95 oC. Composition of deposits was determined with micro-X-
ray dispersed analysis (7). The Auger electronic spectroscopy 
was also used. Figures 2 and 3 show distribution of separate 
impurities across the layer (relative content of deposits was 
determined with height of peak “J” on X-ray radiographs). 
After the layup the content of chloride and silica in the 
surface layer of deposits markedly increased, and after water 
washing with temperature of 95 oC the concentration of both of 
them decreased (Table 2). The data on distribution of impurities 
across the layer before and after the layup show that before the 
layup iron (predominantly in Fe2O3 form) and silica were 
distributed uniformly across the layer, and chloride 
concentrated near the metal surface (Fig. 2). After the layup the 
distribution of impurities in the layer of deposits changed: 
content of Fe2O3, silica, chloride, and calcium near the metal  
Table 1. Amount of Deposits and Specific Sorption of ODA on Heating Surfaces of Hot Water Boilers No. 1 and 8 
(Tube material – Steel 1020) 
 
Amount of deposits 
(hot/cold side), g/m2
Specific sorption of ODA 
(hot/cold side), μg/cm2Specimen cut location 
Before layup After layup 
in 2001 
After shutdown 
in 2002 
After layup 
in 2002 
After shutdown 
in 2003 
  
Hot water boiler No. 1 
Front waterwall, 
tube No. 86 
- 822/723 1,263/806 3.436 0.000/0.079 
Right side waterwall, 
tube No. 73 
- 1,492/1,352 1,878/1,810 0.728 0.017/0.040 
Back waterwall, 
tube No. 164 
- 1,592/1,140 1,006/629 1.469 0.095/0.109 
Left side waterwall, 
tube No. 73   
- 1,078/749 1,404/1,182 0.925 0.087/0.144 
Left double-filament 
waterwall, tube No. 12 
- 943/832 875/865 0.904 0.098/0.098 
  
Hot water boiler No. 8 
Front waterwall, 
tube No. 122 
73/58 105/87 273/146 0.815 0.000/0.118 
Left side waterwall, 
tube No. 77 
187/153 79/37 413/316 0.885 0.090/0.450 
Back waterwall, 
tube No. 55 
266/221 83/37 92/81 0.658 0.154/0.239 
Lower convection part, 
tube No. 5 
207/51 172/72 755/675 1.462 0.256/0.259 
Left double-filament 
waterwall, tube No. 31 
3,177/2,595 548/474 2,275/2,048 12.837 0.167/0.247 
Right side waterwall, 
tube No. 76 
83/77 93/78 349/303 0.592 0.057/0.239 
 
3 Copyright © 2006 by ASME 
: http://www.asme.org/about-asme/terms-of-use
Dow 
Table 2. Content of Some Chemical Substances in Surface Layer of Deposits  
 
Content, % Element Before layup After layup After 1st washing After 2nd washing 
Iron (Fe2O3) 62.656 62.381 63.530 62.988 
Chloride (Cl-) 0.036 0.294 0.409 0.272 
Silica (SiO2) 1.003 1.411 1.079 0.963 
Oxygen (O2) 31.396 30.984 30.740 31.347 
 
 
surface decreased, and near the surface of deposits increased 
(Fig. 3). Thus, these field tests confirm that with the use of 
ODA for the layup of equipment the content of some 
impurities, including chloride, near metal surface decreases 
resulting in less possibility for occurrence of corrosion 
 
Figure 2. Relationship Between Peak Height “J” of Some 
Chemical Elements and Distance “h” from Specimen 
Surface with Deposits before Layup. 
 
 
Figure 3. Relationship Between Peak Height “J” of Some 
Chemical Elements and Distance “h” from Specimen 
Surface with Deposits after Layup with ODA  
(ODA concentration 50 mg/kg).  
nloaded From: https://proceedings.asmedigitalcollection.asme.org on 06/29/2019 Terms of Usprocesses. 
The results produced are in pretty good agreement with the 
data given in (9). It has been shown that in the presence of 
ODA with concentration exceeding 20 ppm, the film is formed 
that reduces corrosion processes. But the difference in the film 
composition in the research (9) and in the present work was 
that in this study the specimens were cut from field equipment, 
i.e. they contacted with real aqueous environment, but not with 
demineralized water. 
CONCLUSIONS 
1. Use of ODA for the layup of district water heaters 
results in reduction of tube failures and deposition 
rate, and stabilization of temperature pattern. 
2. Post-heating season analysis of condition of heat 
exchange surfaces of hot water boilers treated with 
ODA layup shows presence of ODA film on most of 
the surfaces.  
3. After the layup distribution of impurities across the 
height of deposits changes: chloride, calcium, and 
silica move from metal surface to upper portion of 
deposition layer. This results in decrease in 
concentration of corrosive impurities (chloride) near 
metal surface and reduction of corrosion rate. 
4. Implementation of layup procedure with ODA results 
in decrease in corrosion rate during fall/winter heating 
period. 
NOMENCLATURE 
Abbreviations: 
 DWH = district water heater 
 ODA = octadecylamine 
ACKNOWLEDGMENTS 
Authors appreciate contribution of Dr. Andrei Y. Petrov in 
preparation of this paper. 
REFERENCES 
[1] Jonas, O., Machemer, L., and Dooley, R.B., 2001, 
“EPRI ChemExpert: Cycle Chemistry Advisor for Fossil 
Power Plants,” Proc. 6th International Conference on 
Cycle Chemistry in Fossil Plants, 1001363, EPRI, Palo 
Alto, CA, pp. 30.1-30.11. 4 Copyright © 2006 by ASME 
e: http://www.asme.org/about-asme/terms-of-use
Dow[2] Jonas, O., 1985, “Cost of Corrosion and Scale in 
Electric Utilities," EPRI Symposium on Fossil Utility 
Water Chemistry, Atlanta, GA. 
[3] Ryzhenkov, V.A., Petrova, T.I., and Levin, V.A., 2000, 
“Increase in Efficiency and Reliability of Operation of 
Power-Generating Equipment at Power Plants through 
Better Properties of Water and Steam,” Elektricheskie 
Stantsii, 11, pp. 56-57.  
[4] Filippov, G.A., Saltanov, G.A., and Kukushkin, A.N., 
1988, Hydrodynamiocs and Heat-Mass Transfer with 
Filming Amines Present, Energoatomizdat, Moscow, 
USSR. 
[5] Filippov, G.A., Martynova, O.I., Kukushkin, A.N, 
Saltanov, G.A., Dubrovskii, I.Ya, Kurshakov, A.V., 
Petrova, T.I., and Ryzhenkov, V.A., 1999, “Preservation 
of the Equipment of Thermal and Nuclear Power 
Stations by Means of Film-Forming Amines,” Thermal 
Engineering, 46 (4), pp. 307-311. 
 
 
nloaded From: https://proceedings.asmedigitalcollection.asme.org on 06/29/2019 Terms of Use: [6] Ryzhenkov, V.A., Petrova, T.I., Pogorelov, S.I., 
Bublikov, Yu.I., and Bodrov, A.A., 1998, “Universal 
Method of Protection of Power Plant Equipment against 
Corrosion and Wear,” Proc. 3rd International Congress 
“Protection”, Neft I Gaz, Moscow, Russia, pp. 91-92. 
[7] Tomashpolsky, Yu.Ya., 1984, “Methods of Electronic, 
Photonic, and Ionic Scan,” Itogi Nauki I Tekhniki, 10, 
pp. 167-223. 
[8] Dubrovsky, I.Ya. et al, 1989, “Adsorption of 
Octadecylamine on Metal Surface,” Trudy MEI, 208, 
pp. 34-41. 
[9] Ge, H.H., Zhou, G.D., Liao, Q.Q., Lee, Y.G., and Loo, 
B.H., “A Study of Anti-Corrosion Behavior of 
Octadecylamine-Treated Iron Samples,” Applied 
Surface Science, 156, pp. 39-44. 
 
5 Copyright © 2006 by ASME 
http://www.asme.org/about-asme/terms-of-use


FORMATION OF PROTECTIVE FILMS OF OCTADECYLAMINE ON THE SURFACE OF CONSTRUCTION MATERIALS IN THE WATER-STEAM CYCLE AT FOSSIL POWER PLANTS

http://citeseerx.ist.psu.edu/viewdoc/download;jsessionid=E8E8BE7BC7E03C30524257DF9E182EF7?doi=10.1.1.1069.5871&rep=rep1&type=pdf

FORMATION OF PROTECTIVE FILMS OF OCTADECYLAMINE ON THE SURFACE OF CONSTRUCTION MATERIALS IN THE WATER-STEAM CYCLE AT FOSSIL POWER PLANTS

Abstract

Similar works

Full text

Available Versions

CiteSeerX