LAUSR

A key issue associated with combustion of maize straw (MS) is slagging, in order to solve this problem, MS co-combustion with sewage sludge (SS) is a good choice. In this work, co-combustion experiments were conducted in a muffle furnace with SS percentages of 0, 10, 20 and 100% at the temperature of 700 °C, 800 °C, and 900 °C. The effect of SS on MS alkali metals release characteristics was investigated, the ash samples were analyzed by atomic absorption spectroscopy (AAS), X-ray diffraction (XRD), scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS). The results indicate that the potassium in the MS can be captured by Si、Al、Ca、Mg and phosphorus containing inorganic substances in the SS to form a new high melting point compound such as KAlSi2O6, KAlSiO4, KCaFe(PO4)2. Slagging tendency was assessed based on the chemical components and ash fusion temperature (AFT). The evaluation results were highly consistent with the actual slagging conditions.