Quality Improvement of Refuse-Derived Fuel from Landfill Mining

Refuse-derived fuel (RDF) utilization as an alternative fuel has encountered obstacles in complying with industrial quality standards. This study aimed to improve landfill-mined RDF quality for acceptable calorific values (CV), moisture, volatile, ash, fixed carbon, chlorine, and sulfur contents by the cement industry and coal-fired steam power plant. For eight consecutive working days, a minimum of 100 kg of mined material was sampled randomly from transport trucks. Each sample was separated into three fractions: fine (< 10 mm), medium (10–30 mm), and rough (> 30 mm). RDF ratio of plastic: wood and garden waste, originating from a rough fraction, were set at 20:80 to 80:20 with a 10-point interval, including controls at 0:100 and 100:0. Moisture, CV, volatile solids, ash, and fixed carbon contents of RDF were determined by ASTM codes, while chlorine and sulfur used APHA/AWWA/WEF standard methods. The RDF optimum ratio was 40:60, which produced CV, air-dried moisture, volatile solids, ash, fixed carbon, chlorine, and sulfur contents were 25.23 ± 0.53 MJ kg-1, 26.11 ± 2.84%, 75.20 ± 1.21%, 21.18 ± 0.76%, 3.62 ± 0.63%, 0.129 ± 0.009%, and 0.058 ± 0.004%, respectively. These results met industrial RDF quality standards except for moisture, ash, and fixed carbon contents, which needed process improvements at the RDF processing plant.