Work

Biomanufacturing of hydrogen from waste molasses: A full-scale application

Year: 2025

Type: article

Abstract: Biomanufacturing of hydrogen by acidogenic fermentation presents a promising avenue for sustainable hydrogen production; however, data on its full-scale application remain limited. Here we evaluate the performance of a 100 m 3 continuous-flow stirred-tank reactor (CSTR) utilizing waste molasses and inoculated with aerobic excess sludge for hydrogen production. The reactor operated at 35 °C with a constant hydraulic retention time of 5.8 hours, while the organic loading rate (OLR) was incrementally increased from 9.3 to 57.3 kg COD m −3 d −1 . By day 19, stable ethanol-type fermentation was established, yielding an average of 265 m 3 of hydrogen per day. Over the subsequent 72 days, the reactor maintained continuous operation, achieving an average hydrogen production rate of 282 m 3 d -1 at an average OLR of 28.5 kg COD m −3 d −1 . Bioaugmentation with Ethanoligenens harbinense YUAN-3 at a 0.5% volume fraction relative to the mixed liquor volatile suspended solids further enhanced hydrogen production to an average of 348 m 3 d −1 . Despite fluctuations in the OLR between 17.1 and 55.2 kg COD m −3 d −1 , ethanol-type fermentation persisted throughout the bioaugmentation period. These findings demonstrate the viability of full-scale acidogenic fermentation for efficient hydrogen biomanufacturing from high-strength organic wastewater.

Source: Environmental Science and Ecotechnology

DOI: 10.1016/j.ese.2025.100568