Fermentative biohydrogen production by microbes: Process design and engineering control

In this paper, H₂ production by microorganism was reviewed. The characteristic and critical engineering techniques of biohydrogen producing systems are discussed. Fermentative biohydrogen production classified into two main categories (dark fermentation process and photo-fermentation process) is an environmentally benign process, however, the major deterrent of anaerobic fermentation hydrogen production process stems from its lower achievable yields than electrolyze water method and methane cracking method. Strategies of process schematics and design, engineering control parameters, fermentation control, and the technique means to enhance hydrogen evolved and hydrogen evolution rate such as biokinetic control are presented as the emphases. The technology of biohydrogen production at the guild of ethanol-type fermentative biohydrogen-producing theory has been established. The continuous mixed culture and batch pure culture processes were proposed for hydrogen production.