Palm oil mills extract palm oil from the fresh fruit bunches (FFB) for human consumption as well as for producing biodiesel. Since palm oil molecules are made up of only carbon (C), hydrogen (H) and oxygen (O) atoms, the nutrients and minerals present in the crop will remain in the by-products generated by the palm oil mills. With a proper by-products management, the mill could reduce, if not avoid totally the application of chemical fertilisation of the palms for the increased profitability and the sustainable production of palm oil. The main by-products during the FFB processing operation are empty fruit bunches (EFB) (200-220 kg t^-1 of fresh FFB), mesocarp fibre (130-140 kg t^-1 FFB), shell (100-110 kg t^-1 FFB) and palm oil mill effluent (POME)(0.7^-1 m³ t^-1 FFB).