A laboratory system combined empty-fruit-bunch biochar, laccase-producing microbes, a microbial fuel cell and microalgae. It reported 73.15% melanoidin removal, maximum open-circuit voltage of 619.17 mV and carbon fixation of 0.13 g/L/day, without inhibiting rice-seed germination. The integrated concept is promising but not yet validated in full-scale real wastewater.
Key findings
- Maximum melanoidin removal was 73.15 ± 1.10%, accompanied by COD reduction. Maximum open-circuit voltage was 619.17 ± 10.49 mV, current density 8.29 ± 0.15 A/m3 and power density 1.00 ± 0.20 W/m3. Microalgae fixed 0.13 ± 0.00 g/L/day carbon, and the tested effluent did not inhibit rice-seed germination.
Why this matters globally
The waste-to-resource concept may suit coloured palm-oil and agro-industrial effluents in tropical regions by using palm residue as the support while recovering energy. Net energy and economics must include aeration, pumping, lighting and algal harvesting.
Thai researcher contribution
Junjira Thipraksa, Thanapon Yooyen and Pimprapa Chaijak of Thaksin University, together with Wasan Palasai of Princess of Naradhiwas University, form the Thai-affiliated team behind the integrated system.
Limitations to consider
The abstract does not specify run duration, replication or consortium stability, and power remains at prototype scale. A single rice-germination assay cannot establish environmental safety, and carbon fixation should be evaluated net of whole-system life-cycle emissions.