The influence of sulphur additions on the corrosive environment in a waste-fired CFB boiler
Journal article, 2005

Corrosion/deposition field tests have been carried out in the superheater region of a commercial waste-fired 75MW CFBC boiler using air cooled probes. The influence of material temperature (450-500 degrees C), flue gas temperature, temperature variations (i.e. thermal cycling) and additives to the fuel (elemental sulphur and dolomite) on deposition and corrosion was studied. The results presented here mainly consider the influence of sulphur additions to the fuel. The fuel was a mixture of 50% household waste and 50% industrial waste. After exposure the samples were analyzed by ESEM/EDX, XRD, AAS, FIB and IC. With no additional sulphur, alkali chlorides made up a large part of the deposit/corrosion product layer and in some cases chromate (VI) was detected. It is suggested that the chromate (VI) has formed by reaction of the protective oxide with alkali chlorides in the deposit. Adding sulphur to the fuel changed the composition of the deposits, alkali chlorides being largely replaced by alkali sulphates. No chromates(VI) were detected in the sulphur-added runs. It is suggested that adding sulphur to the fuel may decrease fireside corrosion because it changes the composition of the deposit. Alkali sulphates are much less corrosive than alkali chlorides partly because they do not form chromate(VI).

sulphur

waste

alkali

high temperature corrosion

chlorine

field tests

deposits

Author

Jesper Pettersson

Chalmers, Chemical and Biological Engineering, Environmental Inorganic Chemistry

Carolina Pettersson

Chalmers, Chemical and Biological Engineering, Environmental Inorganic Chemistry

Nicklas Folkeson

Chalmers, Chemical and Biological Engineering, Environmental Inorganic Chemistry

Lars-Gunnar Johansson

Chalmers, Chemical and Biological Engineering, Environmental Inorganic Chemistry

Erik Skog

Chalmers, Chemical and Biological Engineering, Environmental Inorganic Chemistry

Jan-Erik Svensson

Chalmers, Chemical and Biological Engineering, Environmental Inorganic Chemistry

Materials Science Forum

0255-5476 (ISSN)

Vol. 522-523 563-570

Subject Categories

Chemical Sciences

More information

Latest update

10/15/2018