A pilot-scale plasma pyrolysis system (PPS) equipped with DC arc plasma torches (DCAPTs) was used to treat solid refuse fuel (SRF) under nitrogen plasma conditions, enabling the direct recovery of carbonaceous particulate matter (PM) through a wet collection process. Unlike conventional thermal conversion systems, in which fine carbonaceous residues are generally treated as secondary waste, this study demonstrates the feasibility of directly recovering plasma-generated PM as a value-added carbon resource at the pilot scale. The recovered PM was collected through a wet collection process, followed by filtration, drying, proximate analysis, and physicochemical characterization. The recovered PM exhibited agglomerated nanoscale morphology with particle sizes of 200–300 nm and inherent water dispersibility due to oxygen-containing surface functionalities. Proximate analysis showed that the ash content decreased from 5.6 wt % to 4.9 wt %, while the fixed carbon content increased significantly from 0.1 wt % to 63.0 wt %. X-ray photoelectron spectroscopy (XPS) revealed a high carbon content (~89 at. %) with C–C/C=C (57.5%), C–O (28.1%), and C=O (13.2%) bonding states. Raman spectroscopy indicated an amorphous carbon structure with a moderate defect density (I D /I G ≈ 0.95), while BET analysis showed a specific surface area of 13.9 m²/g with mesoporous characteristics. The recovered PM exhibited a lower heating value of approximately 6,050 kcal/kg and moderate electrical conductivity (~0.3 S/cm at ~1.5 g/cm³ under 40 MPa compression), indicating its potential as both a high-calorific fuel and a functional carbon material for applications such as electromagnetic interference (EMI) shielding. These results demonstrate the feasibility of simultaneous waste treatment and carbon resource recovery in a pilot-scale plasma pyrolysis process.
Yoo et al. (Fri,) studied this question.