Degradation of Phenolic Compounds in Palm Oil Mill Effluent by Silica-Immobilized Bacteria in Internal Loop Airlift Bioreactors

作者：Khongkhaem Piyamart; Suttinun Oramas; Intasiri Amarawan; Pinyakong Onruthai; Luepromchai Ekawan^*

来源：Clean-Soil Air Water, 2016, 44(4): 383-392.

DOI：10.1002/clen.201300853

• Airlift bioreactor
• Immobilized bacteria
• Palm oil mill effluent
• Phenols
• Wastewater treatment

Palm oil mill effluent (POME) is usually treated using biological systems. However, phenolic compounds remain in the treated POME. This study aimed to remove phenolic compounds from POME using silica-immobilized Methylobacterium sp. NP3 and Acinetobacter sp. PK1. Treated POME samples were collected from the final stabilization ponds of two palm oil mills in Thailand. In batch experiments, the silica-immobilized bacteria effectively degraded 100-500 mg/L phenolic compounds (e.g., caffeic acid, ferulic acid, 4-hydroxybenzoic acid, catechol, and 3-methylcatechol) in synthetic wastewater and completely removed up to 1000 mg/L amended phenol from both treated POME samples. When 25 g/L silica-immobilized bacteria were used in an internal loop airlift bioreactor with a hydraulic retention time of 5h, 83 and 60% of the initial 26.7 and 112 mg/L phenolic compounds in the treated POME samples were removed. The bioreactor was operated continuously for 1200h, and scanning electron microscopy revealed that the bacteria remained trapped inside the silica matrix. This bioreactor could be used for post-treatment of POME.

• 出版日期2016-4