Contamination of Wood Chips with Mineral Soil - Fuel Quality and Combustion Behaviour

Careful operation during fuel production is essential to avoid highshares of mineral soil inwood chips leading to contamination of the biofuels. This can result in elevated gaseous and particulate emissions, corrosion or slag formation during combustion in the biomass boiler. To investigate this effect, stemwood and forest residue wood chip fuels were contaminated with mineral soil at two different ratios. Contamination was done using three typical forest soils from Bavaria (soil A, B and C). Total particulate matter (TPM) emissions increased for wood chips that when contaminated with soil A and C, compared to the reference fuel, but emissions for wood chips contaminated with soil B remained constant. Carbon monoxide (CO) and organic gaseous carbon (OGC) emissions decreased for contaminated wood chips. For NOX emissions, no clear effect was observed. Overall, the contamination of woody biomass had a noticeable effect on pollutant emissions and should be avoided.
Proceedings of the 29th European Biomass Conference and Exhibition, 26-29 April 2021, Online, pp. 662-667