Boiler material optimisation with corrosion probe measurements

S. Tuurna, S. Yli-Olli, P. Pohjanne, J. Meskanen, J. Heikkilä

Research output: Chapter in Book/Report/Conference proceedingConference article in proceedingsScientificpeer-review

Abstract

Combustion of different biofuels and waste generates highly corrosive gases and heavy metals chlorides as well as ashes containing alkaline chlorides and sulphates. Using such fuels in power and CHP boilers can pose a challenge for materials performance, and the pressure to maintain high efficiency increases the challenge further. Heat exchanger tubes may experience substantial thinning leading to premature failure as a result of fireside corrosion during the operation. Such failures cause unpredicted overhauls and availability losses. The change of tube materials in the most critical components is one option to extend the lifetime of components. This paper summarises the results of exposure tests carried out in a CFB boiler using various wood, paper and plastic-based recycled trade and industry fuels suitable for energy use together with peat. The aim of the study was to find alternative tube material for superheater, in location where the current type 347 austenitic stainless steel tube material has experienced fireside corrosion up to 2 mm/a. The exposure test was carried out with air cooled probe exposed in the boiler for a time up to 1400 hours at nominal material temperature of 550 °C. Materials selected for the study were austenitic stainless steels types TP347H (UNS 34709), HR3C (TP310HCbN) and Sanicro 28 (UNS N08028). Following exposure, a section was taken from each specimen and examined using light microscopy and scanning electron microscopy. The results showed chlorine and sulphur species penetrating through grain boundaries into alloy structures. The higher alloying provides better corrosion performance, however all alloys suffered corrosion attack.
Original languageEnglish
Title of host publicationProceedings
Subtitle of host publication10th Conference on Materials for Advanced Power Engineering 2014
Publication statusPublished - 2014
MoE publication typeA4 Article in a conference publication
Event10th Liege Conference on Materials for Advanced Power Engineering - Liege, Belgium
Duration: 14 Sep 201417 Sep 2014
Conference number: 10

Conference

Conference10th Liege Conference on Materials for Advanced Power Engineering
CountryBelgium
CityLiege
Period14/09/1417/09/14

Fingerprint

Boilers
Corrosion
Austenitic stainless steel
Ashes
Superheaters
Peat
Tubes (components)
Biofuels
Alloying
Chlorine
Heavy metals
Optical microscopy
Wood
Grain boundaries
Sulfur
Availability
Plastics
Scanning electron microscopy
Air
Gases

Keywords

  • corrosion monitoring
  • austenitic superheater steel

Cite this

Tuurna, S., Yli-Olli, S., Pohjanne, P., Meskanen, J., & Heikkilä, J. (2014). Boiler material optimisation with corrosion probe measurements. In Proceedings: 10th Conference on Materials for Advanced Power Engineering 2014
Tuurna, S. ; Yli-Olli, S. ; Pohjanne, P. ; Meskanen, J. ; Heikkilä, J. / Boiler material optimisation with corrosion probe measurements. Proceedings: 10th Conference on Materials for Advanced Power Engineering 2014. 2014.
@inproceedings{698f4b2160ce42a2b04eb8058de4a5a8,
title = "Boiler material optimisation with corrosion probe measurements",
abstract = "Combustion of different biofuels and waste generates highly corrosive gases and heavy metals chlorides as well as ashes containing alkaline chlorides and sulphates. Using such fuels in power and CHP boilers can pose a challenge for materials performance, and the pressure to maintain high efficiency increases the challenge further. Heat exchanger tubes may experience substantial thinning leading to premature failure as a result of fireside corrosion during the operation. Such failures cause unpredicted overhauls and availability losses. The change of tube materials in the most critical components is one option to extend the lifetime of components. This paper summarises the results of exposure tests carried out in a CFB boiler using various wood, paper and plastic-based recycled trade and industry fuels suitable for energy use together with peat. The aim of the study was to find alternative tube material for superheater, in location where the current type 347 austenitic stainless steel tube material has experienced fireside corrosion up to 2 mm/a. The exposure test was carried out with air cooled probe exposed in the boiler for a time up to 1400 hours at nominal material temperature of 550 °C. Materials selected for the study were austenitic stainless steels types TP347H (UNS 34709), HR3C (TP310HCbN) and Sanicro 28 (UNS N08028). Following exposure, a section was taken from each specimen and examined using light microscopy and scanning electron microscopy. The results showed chlorine and sulphur species penetrating through grain boundaries into alloy structures. The higher alloying provides better corrosion performance, however all alloys suffered corrosion attack.",
keywords = "corrosion monitoring, austenitic superheater steel",
author = "S. Tuurna and S. Yli-Olli and P. Pohjanne and J. Meskanen and J. Heikkil{\"a}",
year = "2014",
language = "English",
isbn = "978-3-95806-000-5",
booktitle = "Proceedings",

}

Tuurna, S, Yli-Olli, S, Pohjanne, P, Meskanen, J & Heikkilä, J 2014, Boiler material optimisation with corrosion probe measurements. in Proceedings: 10th Conference on Materials for Advanced Power Engineering 2014. 10th Liege Conference on Materials for Advanced Power Engineering, Liege, Belgium, 14/09/14.

Boiler material optimisation with corrosion probe measurements. / Tuurna, S.; Yli-Olli, S.; Pohjanne, P.; Meskanen, J.; Heikkilä, J.

Proceedings: 10th Conference on Materials for Advanced Power Engineering 2014. 2014.

Research output: Chapter in Book/Report/Conference proceedingConference article in proceedingsScientificpeer-review

TY - GEN

T1 - Boiler material optimisation with corrosion probe measurements

AU - Tuurna, S.

AU - Yli-Olli, S.

AU - Pohjanne, P.

AU - Meskanen, J.

AU - Heikkilä, J.

PY - 2014

Y1 - 2014

N2 - Combustion of different biofuels and waste generates highly corrosive gases and heavy metals chlorides as well as ashes containing alkaline chlorides and sulphates. Using such fuels in power and CHP boilers can pose a challenge for materials performance, and the pressure to maintain high efficiency increases the challenge further. Heat exchanger tubes may experience substantial thinning leading to premature failure as a result of fireside corrosion during the operation. Such failures cause unpredicted overhauls and availability losses. The change of tube materials in the most critical components is one option to extend the lifetime of components. This paper summarises the results of exposure tests carried out in a CFB boiler using various wood, paper and plastic-based recycled trade and industry fuels suitable for energy use together with peat. The aim of the study was to find alternative tube material for superheater, in location where the current type 347 austenitic stainless steel tube material has experienced fireside corrosion up to 2 mm/a. The exposure test was carried out with air cooled probe exposed in the boiler for a time up to 1400 hours at nominal material temperature of 550 °C. Materials selected for the study were austenitic stainless steels types TP347H (UNS 34709), HR3C (TP310HCbN) and Sanicro 28 (UNS N08028). Following exposure, a section was taken from each specimen and examined using light microscopy and scanning electron microscopy. The results showed chlorine and sulphur species penetrating through grain boundaries into alloy structures. The higher alloying provides better corrosion performance, however all alloys suffered corrosion attack.

AB - Combustion of different biofuels and waste generates highly corrosive gases and heavy metals chlorides as well as ashes containing alkaline chlorides and sulphates. Using such fuels in power and CHP boilers can pose a challenge for materials performance, and the pressure to maintain high efficiency increases the challenge further. Heat exchanger tubes may experience substantial thinning leading to premature failure as a result of fireside corrosion during the operation. Such failures cause unpredicted overhauls and availability losses. The change of tube materials in the most critical components is one option to extend the lifetime of components. This paper summarises the results of exposure tests carried out in a CFB boiler using various wood, paper and plastic-based recycled trade and industry fuels suitable for energy use together with peat. The aim of the study was to find alternative tube material for superheater, in location where the current type 347 austenitic stainless steel tube material has experienced fireside corrosion up to 2 mm/a. The exposure test was carried out with air cooled probe exposed in the boiler for a time up to 1400 hours at nominal material temperature of 550 °C. Materials selected for the study were austenitic stainless steels types TP347H (UNS 34709), HR3C (TP310HCbN) and Sanicro 28 (UNS N08028). Following exposure, a section was taken from each specimen and examined using light microscopy and scanning electron microscopy. The results showed chlorine and sulphur species penetrating through grain boundaries into alloy structures. The higher alloying provides better corrosion performance, however all alloys suffered corrosion attack.

KW - corrosion monitoring

KW - austenitic superheater steel

M3 - Conference article in proceedings

SN - 978-3-95806-000-5

BT - Proceedings

ER -

Tuurna S, Yli-Olli S, Pohjanne P, Meskanen J, Heikkilä J. Boiler material optimisation with corrosion probe measurements. In Proceedings: 10th Conference on Materials for Advanced Power Engineering 2014. 2014