Hydrogen production by anaerobic digestion in 2 type of reactors; ph and hrt effects

Resumo

Abstract. Hydrogen is a clean energy source of renewable non-conventional type. Its production through anaerobic digestion presents significant benefits such as the possible use of organic waste as raw material for its generation. The pH of the medium, cell residence time (CRT) and the partial pressure of hydrogen are the variables that influence the production of hydrogen by anaerobic digestion. In this study, it was determined the combined effect of cell residence time and pH on the production of hydrogen in 2 reactor configurations: a reactor tank agitated and 2 reactors agitated tank in series. The system of 2 reactors in series showed the best results in terms of hydrogen’s productivity with 6 mmol H2 / L • h and a yield of 3 mmol H2/mmol glucose consumed at a pH of 4.5 and a CRT 12 h These results indicated that it is possible to decrease the effect of the partial pressure of H2 with the use of two tanks in series, close to the operation of a reactor type piston flow.