The Various Applications of a Novel Configuration Anaerobic Fluidized Bed Reactor for Wastewater Treatment

Abstract

In this research, the performance of a novel configuration anaerobic fluidized bed reactor (FBR) was studied for various wastewater treatment applications. According to the use of low density material as supporting media, granular rubber, providing a very low up-flow velocity for inducing fluidization state. The fluidization state inside this reactor was controlled by only feeding with wastewater flowrate. Consequently, this reactor operated without internal recirculation that provided an advantage in term of energy conservation. However, high feeding flow rate was result in a very low hydraulic retention time (HRT). Therefore, the performance of a novel configuration anaerobic FBR should be investigated. There were three experimental parts in this research. In the first part, due to the reactor configuration was modified, liquid flow pattern should be studied. The hydrodynamic behavior was investigated in a novel FBR using a residence time distribution (RTD) experiment. The RTD experimental result showed that the liquid flow pattern was closed to tanks of CSTR (22 – 30 tanks) in series or plug flow behavior. In wastewater treatment application, the novel FBR was performed under low hydraulic retention time (HRT) operation (without internal recirculation), and its performance should be further studied. To evaluate the performance of the reactor, there are two experimental approaches in this research. The first approach, a novel FBR was evaluated for low strength anaerobic wastewater treatment under 50 min of HRT. The novel FBR achieved 86 ± 6% of COD removal efficiency at an organic loading rate (OLR) of 5.6 g COD/L-d. In the second approach, a novel FBR, was performed for treating nitrate with a denitrification process at COD:NO3- - N of 1:1, 2:1, 3:1, 5:1 and 10:1. The highest nitrate removal efficiency was obtained at 99 ± 1%, with COD:NO3- - N ratio of 3:1. The effluent contained low COD and nitrate concentration. The results have confirmed that a novel FBR achieved high performance as anaerobic and denitrification reactor. Moreover, to investigate the relationships between the distribution of microbial community and reactor performance in different reactor operation, this study performed 16S rRNA gene sequencing analysis from granular sludge. The results showed that different OLRs and COD to nitrate ratios affected to dominant microbial community distribution.