Biomass fly ash and biomass bottom ash

Abstract

Biomass comes from organic material such as trees, agricultural and urban waste, plants and shrubs, etc., and it can be used both for electricity production, for example, for heating, and as fuel for transport, and presents important advantages. The use of this resource promotes important economic and social development in rural areas, as well as having environmental benefits due to the elimination of waste and the reduction of CO2 emissions. Biomass energy is close to ‘carbon neutral’. The process of energy production through the combustion of biomass is considered to have important environmental advantages, but it also has the disadvantage of generating large amounts of ash that affect the efficiency in the conversion process of obtaining electrical energy or heating. Ash formed during biomass combustion can be divided into bottom ash and fly ash (FA). Biomass bottom ash is the fraction produced on the grate during primary combustion and is composed of the sand particles purged from the original bed, inorganic components of the feed and the unburned biomass fraction. Biomass FA is a finely divided residue that results from the combustion of biomass and that is transported by flue gasses. The use of ash from the combustion of biomass is conditioned by its physico-mechanical properties, but there is not much literature on the use of these ashes in construction materials. © 2019 Elsevier Ltd. All rights reserved.