M Pourkashanian
The University of Sheffield, UK
Title: Biomass thermodynamic and ash characterization for assessment of impact on boiler tube corrosion, slagging and fouling
Biography
Biography: M Pourkashanian
Abstract
Ash deposition, slagging and fouling on boiler tube surfaces is an inevitable, though undesirable, consequence of burning coal and biomass in power station boilers. The role of fuel characteristics in affecting the form and severity of the problem is significant. In recent years, biomass fuels have gained increasing popularity as an environmentally friendly source of energy in power plants all over the world. This study is based on experimental corrosion tests under controlled atmospheres and characterising the behaviour of four biomass fuels (pine wood, peanut shells, sunflower stalk and miscanthus) using ash fusion temperature (AFT) tests, simultaneous thermal analysis (STA) of fuel ashes, calculation of empirical indices and predicting ash melting behaviour with the help of thermodynamic equilibrium calculations. Corrosion test results indicated increased metal loss but the AFT results failed to show any clear trend between fusion temperature and high alkali content of biomass. STA proved useful in predicting the different changes occurring in the ash. Empirical indices predicted high slagging and fouling hazards for nearly all the biomass samples and this was supported by the possible existence of a melt phase at low temperatures as predicted by thermodynamic calculations.