Title:
Retention of Heavy Metals During the Thermal Conversion of Poultry Litter and Hydrochar
Author(s):
Maj, I., Niesporek, K., Matus, K.
Document(s):
Paper
Abstract:
The study investigated the effect of three aluminosilicate additives—kaolin, halloysite, and bentonite—on the retention of heavy metals in ashes derived from the combustion of two fuels: poultry litter (PL) and hydrochar (HC) produced via hydrothermal carbonization of sewage sludge. The presence of metals in poultry litter may be caused by contamination, intentional addition to feed or administration in the form of supplements. In sewage sludge, heavy metals usually originate from anthropogenic contamination and their presence is higher in sludge from urban wastewater treatment plants. During the combustion of fuels, metals may undergo volatilization and are subject to emission regulations. Consequently, it is essential to minimize their atmospheric release by stabilizing them in ash. The results demonstrated that the incorporation of additives led to a general reduction in the concentration of metals in the ashes. For both fuel types, increased retention of several metals in ashes was observed when any of the aluminosilicates were applied. Notably, halloysite showed the highest efficiency in immobilizing certain elements such as Pb, Ni, Cr, Co, and V, with concentrations of these metals significantly higher in ashes compared to the control samples (PL and HC without additives). By promoting the retention of metals within the solid combustion residues, the additives contribute to reduced atmospheric contamination and improved compliance with increasingly stringent environmental regulations related to air pollution and emissions control.
Keywords:
combustion, heavy metals, poultry litter
Topic:
Biomass Conversion for Bioenergy
Subtopic:
Biomass pre-treatment and production of intermediates
Event:
33rd European Biomass Conference and Exhibition
Session:
4CV.3.7
Pages:
795 - 799
ISBN:
978-88-89407-25-7
Paper DOI:
10.5071/33rdEUBCE2025-4CV.3.7
Price:
FREE
