Influence of Biomass Incineration Temperature on the Content of Selected Heavy Metals in the Ash Used for Fertilizing Purposes

Abstract

This article presents the influence of ash-forming temperature on ash content and the content of selected heavy metals. The biomasses most commonly used in low-power heating boilers, such as miscant, oak, pine, sunflower husk, wheat straw and willow, were selected for the research. The biomass was incinerated at temperatures of 600 °C, 700 °C, 800 °C, 900 °C and 1000 °C, using the X-ray Fluorescence Spectrometer (XRF) for the measurement of element content. The results show that the content of heavy metals in the examined ash was not excessive and could not be considered as potentially dangerous. As the ash-forming temperature increased, the content of Zn, Cd, Cu and Pb decreased, which indicates that, at higher temperatures, they went into the gas phase. Cr, Ni and Fe were thermally stable and less volatile, thus the ashes were enriched with them as the ash-forming temperature increased.