Anaerobic digestion of fungally pre-treated oil palm empty fruit bunches: energy and carbon emission footprint

Abstract

Oil palm empty fruit bunches (OPEFB) is one of the abundant lignocellulosic biomass in Indonesia. However, high lignin content in EFOB has becoming one of the obstacles in valorising it as bioenergy resources, as it is hardly broken down by the microorganisms. Therefore, pre-treatment is often needed to enhance the biodegradation process of organic content in OPEFB. The biological pre-treatment is besieged to enhance the utilisation of OPEFB as bioenergy resources. This study was aimed to investigate the impact of fungal pre-treatment on the OPEFB characteristics and its methane potential, and to estimate the energy and carbon emission saving from anaerobic digestion (AD) of OPEFB. In this study, OPEFB was treated using Phanerocheate chrysosporium under the standard condition and incubated for 7 and 14 days. The energy and carbon emission footprint were calculated using AD Assessment Tool (ADAT) software. The results showed that fungal pre-treatment was able to increase organic matter and enhance methane potential. Estimation on energy (i.e. electrical and heat), however, indicated a lower energy balance and carbon emissions saving for fungal pre-treated OPEFB. The higher moisture content (MC) on treated OPEFB may reduce the biogas and methane production. Yet, further research is still required to have an in-depth understanding of improving the efficacy of biogas production from OPEFB by incorporating other green pre-treatment approaches.

Valorization of oil palm empty fruit bunches into activated carbon: A mini-review

“…In Indonesia, POMs generate around 22.5% of OPEFBs, 14.3% of oil palm mesocarp fibre (OPMF), 6.7% coconut shell, and 5.4% palm oil waste (Suhartini et al, 2022b). OPEFBs are mainly used as fertilizer or directly disposed to the nearby environment (i.e., returned to the plantation area) ( (Hidayat et al, 2020). It is estimated that 1 ton of CPO produced generates 1 ton of OPEFBs (Suhartini et al, 2022b).…”

“…The main components of OPEFBs are cellulose (44.2%), hemicellulose (33.5%), and lignin (20.4%) (Kristiani et al, 2015). OPEFB is a nonwood lignocellulosic biomass rich in organic materials with moisture content in the range of 60-70%, hence suitable for bioenergy and bioproducts production (Ajayi et al, 2023;Hidayat et al, 2020;Ramlee et al, 2019;Suhartini et al, 2020;Suhartini et al, 2022a;Suhartini et al, 2023;Suhartini et al, 2022b). Different range of products can be produced from OPEFBs including alternative fuels (i.e., methanol, bioethanol, dimethyl ether, biohydrogen, biodiesel, bio-solid refuse fuels, etc.)…”

Enhancing anaerobic digestion of wild seaweed Gracilaria verrucosa by co-digestion with tofu dregs and washing pre-treatment

“…Control positive used in this study was α-cellulose powder C8002 (Sigma Alrdrich, Singapore). Control inoculum was prepared using digestate from a full-scale digester treating cattle manure at Balai Besar Pelatihan Peternakan in Batu City, which operated under mesophilic condition, as previously used in our previous studies [12,48,57,58]. The digestate was sieved using a 1 mm screen for removing larger particles, then it was deggased for 48 hours at 37 o C to eliminate the residual biogas.…”

“…A manual BMP test was used in this study, operated for 28 days at 37 o C, following the method explained in our previous studies [12,48,57,58]. Each sample was prepared in triplicate using a 250-mL serum bottle with working volume of 40 mL.…”

Catalytic gasification of oil palm empty fruit bunch by using Indonesian bentonite as the catalyst

“…From 1-ton fresh fruit bunches (FFB) which is ready to be processed in industrial CPO, there will be approximately 23% OPEFB. With a total FFB in 2019 of 42.7 million tons, the number of OPEFB is approximately 8.97 million tons [40]. Evidently, according to Ariffin et al [41], the calorific value of OPEFB is 16 MJ/Kg, so OPE-FB is feasible to convert into syngas though it is lower than coal.…”