Straw pellets combustion in small-scale boilers. Part 2: Corrosion and material optimization.

Published 2008

Citation: Emhofer W, Wopienka E, Schwabl M, Friedl G. Straw pellets combustion in small-scale boilers. Part 2: Corrosion and material optimization, 16th European Biomass Conference 2008, 2nd-6th of June 2008, Valencia, Spain. p1500-1503.

Abstract

This paper presents one part of the results of a project dealing with straw pellets combustion in small
scale combustion systems. Whereas the other part of the work investigates gaseous and particulate emissions, this part focuses on the results of experiments to determine corrosion of refractory material. Three different types of straw
pellets are combusted in a prototype of a 15 kW residential heating boiler. The fuel samples are natural wheat straw,
wheat straw with alumina based additive and wheat straw with a mixture of calcium-/magnesium carbonate based
additive. Combustion experiments are performed under different operating conditions of the test boiler. Three
different types of refractory material are used as combustion chamber material. The refractory materials are different
mixtures of alumina, silica, zirconia and silicium-carbide. The degree of deterioration of these materials is
investigated for temperatures between 700 and 1300 deg C in the presence of slag formed during combustion of the
straw samples and the influence of the fuel additives on corrosion effects is analysed.