Biorefining of oil palm empty fruit bunches for bioethanol and xylitol production in Indonesia: A review

Indonesia has an intensive agro-industrial sector which evolves large volumes of residues each year. Currently, these residues are under-utilized and have a deleterious impact on the environment, Oil Palm Empty Fruit Bunches (OPEFBs) in particular are highly abundant and offer good potential for conversion to bioenergy and bio-based products, in particular bioethanol and xylitol (widely used as an artificial sweetener and can substitute sugar in food and pharmaceutical industries). This paper provides a comprehensive review of the technoeconomic opportunities and challenges for the wider utilization of OPEFBs for the generation of bioethanol and xylitol in Indonesia. This review highlights the significant potential for the valorization of OPEFB based on resource availability in the country (828 MWe/year or 45.86 Mt/year) and growing demand for both bioethanol (from 0.22 billion L in 2019 to 10.38 billion L in 2025) and xylitol (up to 2.20 kt in 2020). Various process configurations were explored to assess the potential for simultaneous co-production of bioethanol and xylitol. A mass balance and techno-economic assessment showed that the preferred scenario was Scenario 3 (co-production of bioethanol with xylitol and lignin) and that this has the potential to generate 46,145 kL bioethanol, 7.716 kt xylitol, and 25.704 kt lignin per year. This is significant given the limited production for both bioethanol and xylitol in the country currently. Further work is required to address challenges around technical, policy and supply chains. This work provides an original and novel strategy to support the wider adoption of commercially viable bioethanol production in Indonesia.

Automated summary

Indonesia's intensive agro-industrial sector generates a large volume of residues, with potential for conversion of Oil Palm Empty Fruit Bunches (OPEFBs) into bioenergy and bio-based products like bioethanol and xylitol. Techno-economic assessment shows potential for simultaneous production of bioethanol, xylitol, and lignin, with significant output to support the wider adoption of commercially viable bioethanol production in Indonesia. Challenges around technical, policy, and supply chains need to be addressed for successful implementation.