Implementation and analysis of temperature control strategies for outdoor photobiological hydrogen production

Koku, Harun
For outdoor photobiological hydrogen production, the effective control of temperature in photobioreactors is a challenge. In this work, an internal cooling system for outdoor tubular photobioreactors was designed, built, and tested. The temperatures in the reactors with bacteria were consistently higher than those without bacteria, and were also strongly influenced by solar irradiation and ambient air temperature. The cooling protocol applied successfully kept the reactor temperatures below the threshold limit (38 A degrees C) required for the bioprocess and provided a uniform distribution of temperature along the reactor tube length. The biomass growth and hydrogen production were similar in the reactors cooled co-currently and counter-currently. The biomass growth rate was 0.1 l/h, the maximum hydrogen production rate was 1.28 mol/m(3)/h, and the overall hydrogen yield obtained was 20 %. The change in the biomass was fitted using the logistic model while cumulative hydrogen production was fitted using the modified Gompertz equation.


Significance of carbon to nitrogen ratio on the long-term stability of continuous photofermentative hydrogen production
Androga, Dominic Deo; Ozgur, Ebru; Eroglu, Inci; Gündüz, Ufuk; Yucel, Meral (2011-12-01)
The stable and optimized operation of photobioreactors (PBRs) is the most challenging task in photofermentative biological hydrogen production. The carbon to nitrogen ratio (C/N) in the feed is a critical parameter that significantly influences microbial growth and hydrogen production. In this study, the effects of changing the C/N ratio to achieve stable biomass and continuous hydrogen production using fed-batch cultures of Rhodobacter capsulatus YO3 (uptake hydrogenase deleted, hup-) were investigated. Th...
Investigation of the effects of initial substrate and biomass concentrations and light intensity on photofermentative hydrogen gas production by Response Surface Methodology
Akman, Melih Can; Bayramoğlu, Tuba Hande; Gündüz, Ufuk; EROĞLU, İNCİ (2015-04-27)
Biohydrogen, which can be produced by dark fermentation and photofermentation processes, is a renewable and clean approach for hydrogen production. In this study, it was aimed to determine the operational conditions which satisfy the highest photofermentative hydrogen production rate in batch reactors. To that purpose, the effects of initial substrate concentration, initial volatile suspended solids (VSS) concentration and light intensity on photofermentation process, and their interactive effects were inve...
Photofermentative hydrogen production from molasses in tubular photobioreactor with pH control
Oflaz, Fatma Betül; Koku, Harun; Department of Chemical Engineering (2019)
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...
Scale-up studies for stable, long-term indoor and outdoor production of hydrogen by immobilized Rhodobacter capsulatus
Sagir, EMRAH; ALIPOUR, Siamak; ELKAHLOUT, Kamal; Koku, Harun; Gündüz, Ufuk; Eroglu, Inci; YUCEL, Meral (2017-09-07)
Photofermentative hydrogen production by immobilized Rhodobacter capsulatus YO3 was carried out in a novel photobioreactor in sequential batch mode under indoor and outdoor conditions. Long-term H-2 production was realized in a 1.4 L photobioreactor for 64 days using Rhodobacter capsulatus YO3 immobilized with 4% (w/v) agar on 5 mM sucrose and 4 mM glutamate. The highest hydrogen yield (19 mol H-2/mol sucrose) and hydrogen productivity (0.73 mmol H-2 L-1 h(-1)) were achieved indoors on 5 mM sucrose. The eff...
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...
Citation Formats
D. D. ANDROGA, B. UYAR, H. Koku, and İ. EROĞLU, “Implementation and analysis of temperature control strategies for outdoor photobiological hydrogen production,” BIOPROCESS AND BIOSYSTEMS ENGINEERING, pp. 1913–1921, 2016, Accessed: 00, 2020. [Online]. Available: