Co-combustion characteristics of municipal solid waste with coal gangue and its HCl emission

Co-firing of municipal RDF and coal gangue in existing coal gangue power station is a potential treatment way of municipal solid waste and coal gangue. The co-combustion characteristic of municipal solid waste (MSW) and coal gangue was investigated by thermogravimetric analyzer. The HCl emission in co-combustion of coal gangue with PVC, NaCl and MSW were also studied using a high-temperature tube furnace combustion system. The results show that the combustion characteristic of coal gangue can be improved obviously with blending of MSW, especially for devolatilization and ignition characteristics. In consideration of combustion characteristics, the MSW blending ratio of 20% is suggested. When the blending ratio of PVC or NaCl is low, the existence of coal gangue can inhibit the release of HCl in PVC while promote the release of HCl in NaCl. As the increase of blending ratio, the effect decreases gradually. In co-combustion of MSW and coal gangue, the release ratio and concentration of HCl is increased. When the MSW blending ratio is 10%, the HCl emission concentration is 56.22 mg/m³ which exceeds the national standard. Hence, the dechlorination measurement should be considered.