Analysis of the cyanobacterial hydrogen photoproduction process via model identification and process simulation. (25th May 2015)

• Record Type: Journal Article
• Authors: Zhang, Dongda; Dechatiwongse, Pongsathorn; Del-Rio-Chanona, Ehecatl Antonio; Hellgardt, Klaus; Maitland, Geoffrey C.; Vassiliadis, Vassilios S.
• Is Part Of: Chemical engineering science. Volume 128(2015)
• Page Start: 130
• Page End: 146
• Publication Date: 2015-05-25
• Subjects: Biohydrogen -- Cyanobacteria -- Photoproduction -- Kinetic models -- Process simulation -- Bioreactor design; Chemical engineering -- Periodicals; Génie chimique -- Périodiques; Chemical engineering; Periodicals; Electronic journals; 660
• DOI: 10.1016/j.ces.2015.01.059
• Languages: English
• ISSNs: 0009-2509

Abstract

Abstract: Cyanothece sp. ATCC 51142 is considered a microorganism with the potential to generate sustainable hydrogen in the future. However, few kinetic models are capable of simulating different phases of Cyanothece sp. ATCC 51142 from growth to hydrogen production. In the present study four models are constructed to simulate Cyanothece sp. batch photoproduction process. A dynamic optimisation method is used to determine parameters in the models. It is found that although the piecewise models fit experimental data better, large deviation can be induced when they are used to simulate a process whose operating conditions are different from the current experiments. The modified models are eventually selected in the present study to simulate a two-stage continuous photoproduction process. The current simulation results show that a plug flow reactor (PFR) shows worse performance compared to a continuous stirred-tank reactor (CSTR) in the current operating conditions since it lowers the total hydrogen production. The finding is that nitrate and oxygen concentration change along the direction of culture movement in PFR, and hydrogen is only generated in the zone where both of them are low. The reactor area thereby is not well utilised. Additionally, as hydrogen production rate is primarily influenced by biomass concentration, which increases initially and decreases eventually along the direction of culture movement, the overall hydrogen production rate in a PFR may be lower than that in a CSTR. Finally, in this study fed-batch photoproduction processes are proposed containing only one photobioreactor based on the current simulation. Abstract : Highlights: Dynamic simulation models for cyanobacterial hydrogen production process. Parameter estimation via dynamic optimisation. Proposed modified models exhibit higher accuracy for real process simulation. Interpretation of higher performance of CSTR over PFR for this process. Fed-batch processes are proposed as the optimal reactor operation.