A large volume of oil palm empty fruit bunch (EFB) is generated as waste feedstock around the globe. This abundant waste containing 0.75% oil on average could be a promising feedstock for biodiesel production if oil recovery could be accomplished in an economicallyviable and environmentally-friendly manner. To achieve that, a new method called High Pressure Water Spray (HPWS) system was introduced and performed by spraying pressurized water (500 psi) at 30 °C, 60 °C, and 90 °C and combination of water-steam at 120 °C and 150 °C onto the surface of the oil palm empty fruit bunches (EFB). The results obtained indicated that, the highest oil removal yield of 94.41 ± 0.02 wt% was obtained at 150 °C. Moreover, bioprospection of biodiesel properties based on fatty acid methyl ester (FAME) profile revealed that the biodiesels produced from the fresh crude palm oil and residual oil were comparable and were in accordance with international standards. In addition to that, the HPWS process led to an enhanced quality of the remaining lignocellulosic materials for conversion into other value added bio-products such as ligno-ethanol by decreasing lignin content and increasing cellulose content. In view of environmental impact assessment, the HPWS system showed favorable impacts on all the end-point damage categories especially in resources damage category. Moreover, economic assessment showed that the recovered CPO could be generated at a low price of USD 0.41 vs. USD 0.66 for CPO. Overall, this process could drastically increase the market value of an abundant type of waste in many parts of the world, i.e., EFB leading to the generation of additional wealth for the palm oil industry.

Various applications of oil palm empty fruit bunches (OPEFB) would be hindered by the presence of residual oil. This study aimed to remove and recover the residual oil from OPEFB using an integrated system, high pressure water spray system (HPWSS). The performance of the HPWSS was evaluated at different temperatures and water pressures, and the residual oil collected was recovered through water shaking method and tested for biodiesel application. A maximum of 84.9% of residual oil was removed by HPWSS at 60 °C and 8960 kPa and the highest residual oil recovery of 58.8% was observed at 95 °C, using power shaking 5 and 90% of dilution. The following ranges of deterioration of bleachability index (DOBI), free fatty acid (FFA), and peroxide value (PV) for the residual oil were 1.21 to 2.67, 7.11 to 10.4%, and 4.85 to 7.56, respectively. Biodiesel with different blends of recovered residual oil (5%, 10%, and 15%) showed lower values (9.87, 9.57, and 9.56 Nm) of brake torque as compared with diesel (10.89 Nm). Overall, this study showed the potential of HPWSS to obtain an acceptable quality of residual oil from OPEFB to be used in any value-added product generation.