Physicochemical Properties And Charge Performance Studies Of Biomass/coal Co-firing Ash

This paper presents results of experimental investigation about chemical compositions, morphologies, immersion, cohesion properties and charge performance of ashes generated from the co-combustion of different types of coals and biomass fuels. The produced data show that the presence of large amounts of alkali metals in the three biomass fuels, compared to coal, which make the co-combustion ashes become more hygroscopic with the increase of biomass in fuel mixture. The adhesive power of co-combustion ash rises when there is a little of biomass mixed in the fuel mixture, reduces when there is too much biomass mixed in. The morphology of co-combustion ash is much different from the morphology of ashes from pure combustion of coal or biomass. The charge performance of ash generated from the co-combustion of different types of coals and biomass fuel(corn stalk) using faraday-cup detector and electrical low pressure impactor(ELPI). The produced data show that the charge capacity of co-combustion ash rises a little with the increase of biomass in fuel mixture. The reason is that different types of co-combustion ash has different chemical compositions and structural features which increases the relative dielectric constant, specific resistance and surface adsorptive ability and those make the charge performance of co-combustion ash promote. Although the addition of biomass in fuel mixture rises the charge capacity of co-combustion ash, the size of particle is still the main influence factor of its charge performance. Results in this paper may provide biomass/coal co-combustion power station with information on looking for alternative biofuels and appropriate blending ratio in order to avoid making ash-related problems.