Physico-chemical changes during co-composting of chipped-ground oil palm frond and palm oil mill effluent.

The aim of this study was to investigate the physicochemical changes during co-composting of chippedground oil palm frond (CG-OPF) and palm oil mill effluent (POME). Results showed that co-composting of CG-OPF and POME was completed within 60 days with average C/N ratio of 23. Temperature of the compost observed in thermophilic phase was at 53.5oC after four days of composting (DOC). The highest temperature observed during thermophilic phase was 56oC at 21 DOC. The oxygen level, moisture content and pH of the compost were maintained at 1.7% 12.2%, 60.6% 70.7% and 7.9 – 8.5, respectively, throughout the 60 DOC. The total bacteria count observed was 55x1010 cfu ml-1 at the initial stage and decreased to 14.7x1010 cfu ml-1 on 25th DOC and 3.7x1010 cfu ml-1 on 60th DOC. The C/N ratio observed was 63.9 at the initial stage and decreased to 24 on 60th DOC.