Abstract
The vegetable juice waste (VJW) was a sample treated in the IC reactor after squeezing. The experimental procedure was divided into five phases based on OLR (1.4, 2.2, 4.4, 8.4, and 17.6 g COD/l.d, respectively) and HRT (6, 4, 2, 1, and 0.5 days, respectively) in this investigation to assess the performance of an internal circulation anaerobic (IC) reactor in the conversion of vegetable juice waste (VJW) to biogas production at ambient temperature for 160 days. The experiment results showed that the biogas production yield of the IC reactor in phase 1 was 6.9 gVS/l.d higher than in other phases 2, 3, 4, and 5, respectively, where biogas production was 2.8, 3.1, 1.6, and 0.9 gVS/l.d, respectively. The variation in methane content of biogas generated remained constant between 66 and 69%, corresponding to OLR of 1.4, 2.2, 4.4, 8.4, and 17.6 gCOD/l.d, respectively. The variation decreased steadily from 6 to 0.5 days at HRT. When an OLR was gradually increased from 1.4–17.6 gCOD/l.d with an HRT of 4-0.5 days for 160 days, COD removal ranged from 94 − 80%. However, during the execution of an IC reactor process, indicating a drop in the HRT, the system did not overload. The IC reactor system is a beneficial method for the current and further conversion of vegetable juice waste or wastewater treatment to biogas production, as well as providing scientific information to those who are interested in future research.