Ash melting behavior

Ash melting behavior in biomass-fuelled fluidised beds

Fluidised bed combustion is predestined for the use of biofuels. Low ash melting temperatures, however, often result in operational problems and plant damage in commercial facilities. The main reason for this is the composition of the biomass and to be more precise the high contents of alkalis and chlorine. These cause low ash melting points and are thus responsible for the formation of agglomerates which subsequently lead to the defluidisation of the fluidised bed. Costly repairs and lengthy plant shutdowns are the result.

 

rem-aschecoatings
SEM investigations show the structure of ash coating on bed material particles

 

The focus of EVT’s research lies on the development of appropriate measurement methods to predict and prevent these problems in order to extend the range of use of biofuels. The aim is to develop and test new, innovative concepts by systematically examining emerging phenomena.

 

lapis-agglomerate
Agglomerates from the L.A.P.I.S. experimental reactor. The growth of the single sand grains into large clusters leads to the collapse of the fluidised bed

 

Contact:

Dr.-Ing. Dominik Müller

Department of Chemical and Biological Engineering
Lehrstuhl für Energieverfahrenstechnik