TOWARDS BETTER UNDERSTANDING OF TEMPERATURE GRADIENTS IN SUPERHEATER CORROSION

B3 Icke-referentgranskade konferenspublikationer


Interna författare/redaktörer


Publikationens författare: Markus Engblom, Daniel Lindberg, Patrik Yrjas, Jonne Niemi, Tor Laurén, Mikko Hupa
Redaktörer: Jinghai Li, Fei Wei, Xiaojun Bao, Wei Wang
Förlagsort: Beijing
Publiceringsår: 2014
Förläggare: Institute of Process Engineering, Chinese Academy of Sciences
Moderpublikationens namn: 11th International Conference on Fluidized Bed Technology, CFB-11


Abstrakt

This paper presents a novel laboratory method for superheater corrosion experiments in which a temperature gradient is applied over the deposit and steel. Experiments using salt mixtures of NaCl/Na2SO4 or KCl/K2SO4 show alkali chloride transport (NaCl, KCl) within the salt layer, and to the steel surface. The alkali chloride is vaporized from the salt grains, transported down the temperature gradient, and deposited on surfaces with lower temperature. Mathematical model predictions show the governing transport process to be temperature gradient induced concentration diffusion, not thermal diffusion. The transport rate is species-dependent, with a greater transport rate of KCl as compared to NaCl. Further work is needed for a better understanding of the implications of temperature gradients for superheater corrosion in boiler environments.


Nyckelord

Alkali chloride induced corrosion, corrosion, high-temperature corrosion, lab-scale corrosion measurements

Senast uppdaterad 2019-20-11 vid 05:08