To read this content please select one of the options below:

Research into the characteristics of furnace tube oxide film in CPT, CT, AVT(R) and AVT(O) water chemistry conditions

Zhiping Zhu (School of Chemistry and Biological Engineering, Changsha University of Science and Technology, Changsha, China)
Hui Zhang (School of Chemistry and Biological Engineering, Changsha University of Science and Technology, Changsha, China)
Linlin Jing (School of Chemistry and Biological Engineering, Changsha University of Science and Technology, Changsha, China)
Shuhua Xiong (School of Chemistry and Biological Engineering, Changsha University of Science and Technology, Changsha, China)
Zhenghui Tan (School of Chemistry and Biological Engineering, Changsha University of Science and Technology, Changsha, China)

Anti-Corrosion Methods and Materials

ISSN: 0003-5599

Article publication date: 17 March 2012

1541

Abstract

Purpose

The purpose of this paper is to research the morphologies of the oxide films formed on the internal surfaces of water wall tubes in a 600 MW furnace at 300° while using CPT, CT, AVT(R) and AVT(O) water chemistry. In these water chemistry conditions, a layer of oxide film spontaneously forms in the furnace wall which could prevent corrosions in boiler water directly contact with the inner tube and reduce the probability of tube perforation.

Design/methodology/approach

The different morphologies, specific functions and distribution in the oxide film were identified by electrochemical workstation, XRD, SEM and EDAX.

Findings

It is concluded that metal surface was rugged and had deep corrosion in CPT. Ions penetrated into the oxides of large particles with gaps and intergranular corrosion occurred in CT conditions. In AVT(R), the oxide film uniformly covered on the metal surface played a protective role, but could be easily washed away by solution. The oxide film formed in AVT(O) was similar to AVT(R), but the difference is that large solid particles of Fe2O3 cover the outermost oxide film, which prevents the oxide film from being taken away by the flowing solution. In consequence, the degree of corrosion sustained by the tube walls is lowest in the case of AVT(O).

Originality/value

The results can provide reference for reducing the high temperature corrosion of metal in the actual operation.

Keywords

Citation

Zhu, Z., Zhang, H., Jing, L., Xiong, S. and Tan, Z. (2012), "Research into the characteristics of furnace tube oxide film in CPT, CT, AVT(R) and AVT(O) water chemistry conditions", Anti-Corrosion Methods and Materials, Vol. 59 No. 2, pp. 81-87. https://doi.org/10.1108/00035591211210857

Publisher

:

Emerald Group Publishing Limited

Copyright © 2012, Emerald Group Publishing Limited

Related articles