Date:

2025-04-30

Title of Paper:

Corrosion characteristics of 316L as transpiring wall material in supercritical water oxidation of sewage sludge

Journal:

International Journal of Hydrogen Energy

Summary:

Systematical corrosion tests of austenitic stainless steel 316L exposed to sewage sludge
SCWO (supercritical water oxidation) were conducted in a batch stirred reactor with
hydrogen peroxide as oxidant. Experiment conditions such as temperature, oxidation coefficient,
pH value, corrosion medium, were chosen mainly keeping in mind the place and
environment of reactions (i.e. surrounding transpiring wall). The exposed samples were
ultimately analyzed by weight measurement, scanning electron microscopy in conjunction
with energy dispersive spectroscopy, and X-ray diffraction analysis. The results show that
severe pitting corrosion occurred as the sample was exposed to complicated environments,
and different oxides including Fe3O4, FeCr2O4 and MoO3 were found on the sample surface.
The corrosion rate at all test conditions (360e450
C pH¼ 5.2e10.05, oxidation coefficient of
0e2.0, sewage sludge or its SCWO reactor effluent) was in the range of 0.12e0.66 mm/y, and
it increased as temperature and OC increased at supercritical conditions. Moreover, potential
corrosion mechanism of 316L in sewage sludge SCWO is proposed, and influences
of operating parameters on 316L corrosion properties are summarized. 316L and reactor
effluent could be considered as transpiring wall material and transpiring water in sewage
sludge SCWO with transpiring wall reactor, respectively.

Co-author:

Donghai Xu, Zhijiang Ma, Shuwei Guo, Xingying Tang, Yang Guo, Shuzhong Wang

Volume:

( 2 0 1 7 )

Page Number:

1-1 0

Translation or Not:

No

Date of Publication:

2017-05-27