Effect of reduced graphene oxide (rGO) addition on biogas and biomethane production from domestic organic waste

The aim of this thesis is to obtain biogas and biomethane from organic wastes obtained from Nigde Municipality Solid Waste Storage Facility by anaerobic fermentation. In this study using batch reactors, reduced graphene oxide (rGO) was used as the conductive material. Optimization studies were carried out in batch reactors to determine the ideal S/I ratio and rGO dosage following the characterization processes. In the study, 6 different S/I ratios (0, 0.5, 1, 2, 3 and 4 gUK/gUK) and different rGO concentrations (0-10-20-30 mg/L) were selected. The highest results for biogas and biomethane production were obtained as 815.66 mL/gUK and 525.12 mL/gUK at the S/I=1 ratio and 20 mg/L rGO dosing. The highest total solids (TKM) and volatile solids (VOC) removal rates were observed in the S/I 1 gUK/gUK reactor, consistent with the highest biomethane yield. The reactor with the best production of biogas and methane, containing S/I=1 gUK/gUK and 20 mg/L rGO, is the reactor with the highest number of volatile organic acid species (acetic acid 3.65%; propionic acid 13.82%; butyric acid). 15.7%; iso-valeric acid 10.16%). When TOC concentrations in the reactors were evaluated, TOC values were close in S/I=0-0.5 and 1 gUK/gUK sample.