Photofermentative hydrogen production from molasses in tubular photobioreactor with pH control

Download

index.pdf

Date

2019

Author

Oflaz, Fatma Betül

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

226
views

108
downloads

Biological hydrogen production has the potential to supply hydrogen from various wastes as feedstock and operation under ambient conditions. In order to obtain cost effective production, photobioreactors (PBRs) that can operate for long durations while utilizing waste are necessary. Two primary issues limiting the duration are decrease in pH and the non-optimal C/N ratio. The main aim of this study was to construct and operate a pH control system for a pilot scale photobioreactor (20 L) to achieve prolonged outdoor hydrogen production from molasses by R. capsulatus by stabilizing pH during operation. Optimum C/N ratio was also investigated for molasses utilization by R. capsulatus for indoor and simulated outdoor conditions in small scale photobioreactors in batch mode. Simulated outdoor conditions for day and night cycle were designed as indoor experiments with changing temperature and light/dark cycle. Effects of constant pH under indoor were investigated to increase molasses utilization in small scale. Long-term outdoor hydrogen production on diluted molasses in a pilot-scale PBR using photofermentative bacteria was demonstrated. The experiment lasted 48 days and carried out on August 16 and October 2, 2017. PID control system was chosen to control pH and it was successfully implemented. The highest productivity was 0.69 mol H2/(m3.h). For small-scale experiments, the C/N ratio was decided as 45 and the highest productivities were 0.38 and 0.69 mol H2/(m3.h), under indoor and simulated outdoor conditions, respectively. With constant pH conditions, molasses concentration could be increased to 15 from 5 mM with better productivity.

Subject Keywords

Fermentation., Keywords: Photofermentation, pH control, Rhodobacter capsulatus, Molasses, C/N ratio, Outdoor

URI

http://etd.lib.metu.edu.tr/upload/12623605/index.pdf
https://hdl.handle.net/11511/43739

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

Photofermentative hydrogen production from molasses: Scale-up and outdoor operation at low carbon-to-nitrogen ratio Savasturk, Dilan; Kayahan, Emine; Koku, Harun (2018-06-28) Photofermentative hydrogen production was carried out under outdoor conditions with a Rhodobacter capsulatus strain on molasses, a renewable and sustainable feedstock. An existing photobioreactor design was scaled-up from 9 L to 20 L. The decreased carbon-to nitrogen (C/N) ratio of 13.0, compared to our previous work, accelerated growth and resulted in a reduced lag period for hydrogen production as well as higher productivities in the exponential phase. However, the low C/N ratio also promoted a high optic...
Potential use of thermophilic dark fermentation effluents in photofermentative hydrogen production by Rhodobacter capsulatus Ozgur, Ebru; Afsar, Nilufer; de Vrije, Truus; Yucel, Meral; Gündüz, Ufuk; Claassen, Pieternel A. M.; Eroglu, Inci (2010-01-01) Biological hydrogen production by a sequential operation of dark and photofermentation is a promising route to produce hydrogen. The possibility of using renewable resources, like biomass and agro-industrial wastes, provides a dual effect of sustainability in biohydrogen production and simultaneous waste removal. In this study, photofermentative hydrogen production on effluents of thermophilic dark fermentations on glucose, potato steam peels (PSP) hydrolysate and molasses was investigated in indoor, batch ...
Biohydrogen production from beet molasses by sequential dark and photofermentation Ozgur, Ebru; Mars, Astrid E.; Peksel, Beguem; Louwerse, Annemarie; Yucel, Meral; Gündüz, Ufuk; Claassen, Pieternel A. M.; Eroglu, Inci (2010-01-01) Biological hydrogen production using renewable resources is a promising possibility to generate hydrogen in a sustainable way. In this study, a sequential dark and photofermentation has been employed for biohydrogen production using sugar beet molasses as a feedstock. An extreme thermophile Caldicellulosiruptor saccharolyticus was used for the dark fermentation, and several photosynthetic bacteria (Rhodobacter capsulatus wild type, R. capsulatus hup(-) mutant, and Rhodopseudomonas palustris) were used for t...
Photobiological hydrogen production by Rhodobacter sphaeroides O.U.001 by utilization of waste water from milk industry Turkarslan, S; Yigit, DO; Aslan, K; Eroğlu, İnci; Gündüz, Ufuk (1997-06-26) Hydrogen production with photosynthetic microorganisms contributes to the protection of the environment, not only in producing a clean fuel but also in waste treatment processes. In this study, Rhodobacter sphaeroides, a photosynthetic bacteria, is used in photobiological hydrogen production by using waste water from the milk industry.
Amelioration of photofermentative hydrogen production from molasses dark fermenter effluent by zeolite-based removal of ammonium ion Androga, Dominic Deo; Ozgur, Ebru; EROĞLU, İNCİ; Gündüz, Ufuk; Yucel, Meral (2012-11-01) One of the challenges in the development of integrated dark and photofermentative biological hydrogen production systems is the presence of ammonium ions in dark fermentation effluent (DFE). Ammonium strongly inhibits the sequential photofermentation process, and so its removal is required for successful process integration. In this study, the removal of ammonium ions from molasses DFE using a natural zeolite (clinoptilolite) was investigated. The samples were treated with batch suspensions of Na-form clino...

Citation Formats

F. B. Oflaz, “Photofermentative hydrogen production from molasses in tubular photobioreactor with pH control,” Thesis (M.S.) -- Graduate School of Natural and Applied Sciences. Chemical Engineering., Middle East Technical University, 2019.