The combination of
baffled air flotation and a membrane system for the treatment of palm oil mill
effluent (POME) was studied. The POME was obtained from a palm oil factory in
PTPN I Tanjong Seumantoh, Aceh, Indonesia. Operation variables and conditions,
such as the hydraulic retention time and air flow rates, were varied to find
the optimum process. The air flotation process is able to reduce the
concentration of suspended solids and fats/ oils contained in the wastewater,
which increases the performance of the membrane by reducing clogging. The
results showed that this method was promising for POME treatment. The optimum
organic removal efficiency of the air flotation pretreatment was obtained at
HRT = 5 days and at an air flow rate of 11 L/min. The effluent was subsequently
passed through an anaerobic membrane system to achieve the highest removal
efficiency treatment. The removal efficiency of chemical oxygen demand (COD),
total suspended solids (TSS), turbidity, mixed liquor suspended solids (MLSS),
mixed liquor volatile suspended solids (MLVSS), and fats/oils after passing
through the membrane system were 97%, 93.9%, 99.8%, 94.5%, 96.2%, and 99.9%,
respectively. The results also showed that the pH could be neutralized to 6.18,
while a dissolved oxygen (DO) level of 1.60 mg/L could be achieved. A high
quality of effluent was obtained, which met the standards for POME effluent.