Biohydrogen production by lactate-driven dark fermentation of real organic wastes derived from solid waste treatment plants

Cristina Martínez-Fraile; Raúl Muñoz; María Teresa Simorte; Inmaculada Sanz; Octavio García-Depraect

doi:10.1016/j.biortech.2024.130846

Biohydrogen production by lactate-driven dark fermentation of real organic wastes derived from solid waste treatment plants

Bioresour Technol. 2024 May 15:403:130846. doi: 10.1016/j.biortech.2024.130846. Online ahead of print.

Authors

Cristina Martínez-Fraile¹, Raúl Muñoz¹, María Teresa Simorte², Inmaculada Sanz², Octavio García-Depraect³

Affiliations

¹ Institute of Sustainable Processes, Dr. Mergelina s/n, 47011 Valladolid, Spain; Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina, s/n, 47011 Valladolid, Spain.
² FCC Medio Ambiente, Avenida Camino de Santiago 40, CTR de Valladolid, Madrid 2850, Spain.
³ Institute of Sustainable Processes, Dr. Mergelina s/n, 47011 Valladolid, Spain; Department of Chemical Engineering and Environmental Technology, School of Industrial Engineering, University of Valladolid, Dr. Mergelina, s/n, 47011 Valladolid, Spain. Electronic address: octavio.garcia@uva.es.

PMID: 38754561
DOI: 10.1016/j.biortech.2024.130846

Abstract

This study evaluated the hydrogen production potential through lactate-driven dark fermentation (LD-DF) of organic wastes from solid waste treatment plants, including the organic fraction of municipal solid waste (OFMSW), mixed sewage sludge, and two OFMSW leachates. In initial batch fermentations, only OFMSW supported a significant hydrogen yield (70.1 ± 7.7 NmL-H₂/g-VS added) among the tested feedstocks. Lactate acted as an important hydrogen precursor, requiring the presence of carbohydrates for sequential two-step lactate-type fermentation. The impact of operational pH (5.5-6.5) and initial total solids (TS) concentration (5-12.5 % w/w) was also evaluated using OFMSW as substrate, obtaining hydrogen yields ranging from 6.6 to 55.9 NmL-H₂/g-VSadded. The highest yield occurred at 6.5 pH and 7.5 % TS. The LD-DF pathway was indicated to be present under diverse pH and TS conditions, supported by employing a specialized microbial consortium capable of performing LD-DF, along with the observed changes in lactate levels during fermentation.

Keywords: Dark fermentation; Food waste; Leachate; Mixed sludge; OFMSW.