Performance evaluation of hybrid upflow anaerobic sludge blanket reactors with different inert media for sewage treatment

In this study, three HUASB reactors with different inert media viz. sea shells (R1), polyvinyl alcohol (PVA) gel beads (R2) and coconut fiber (R3), were simultaneously investigated in continuous mode at an ambient temperature ranging from 33 degrees C to 41 degrees C for six months. The reactors were employed with varying hydraulic retention times (starting from 6 h and reduced to 2 h) and organic loading rates (0.5-6.0 kg.COD.m(-3).day(-1)) for sewage treatment. Sludge bed samples from each reactor were collected at the end of the process, and particle size distribution was determined using ocular micrometry, as well as the number of microorganisms present per ml using the neubauer chamber. According to the chemical and microbiological analysis, along with an overall assessment, it was found that the HUASB reactor with coconut fiber inert media has proved superior in its performance compared to the HUASB reactor with PVA gel beads and sea shells.