Removal of Low and High Residual Oil and Suspended Solid in Palm Oil Mill Effluent ByAnaerobic Hybrid Sludge Bed Fixed Film Reactor

摘要

Residual suspended solid (SS) and oil & grease (O&G) in palm oil mill effluent (POME) are one of the main causes to affect the performance and stability of anaerobic digestion system. The concentrations of low and high strength of SS and O&G were carried out to study the capability of laboratory-scale anaerobic hybrid sludge bed-fixed film reactor (AHR) treating POME with lO days of HRT was completed at mesophilic temperature (35-37 °C). In this study, it was found that concentrations of SS and O&G in POME directly effect to process stability and performance via organic acid formation and organic removal efficiency. At low SS and O&G concentration, the removal efficiencies of total COD (TCOD), O&G and SS reached 82, 77 and 65 %, respectively. In addition, biogas and methane were produced 23 and 1.3 L/day, respectively, under normal condition of process stability. For high strength of SS and O&G, TCOD and SS were removed up to 87 and 78%, respectively, wbile O&G decreased to 55 %. The TVA/Alkalinity ratio was slightly higher than 0.5 and lead to small increasing of biogas and methane production. O&G removal efficiency was more sensitive to environment than SS, especially acidity condition. However, AHR can perform well even at high SS and O&G concentration, if we can optimize and increase methanogens in the system.