Influence of substrate concentration on the stability and yield of continuous biohydrogen production

G. Kyazze*, N. Martinez-Perez, R. Dinsdale, G. C. Premier, F. R. Hawkes, A. J. Guwy, D. L. Hawkes

*Awdur cyfatebol y gwaith hwn

    Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid


    The effect of substrate concentration (sucrose) on the stability and yield of a continuous fermentative process producing hydrogen was studied. High substrate concentrations are attractive from an energy standpoint as they would minimise the energy required for heating. The reactor was a CSTR; temperature was maintained at 35°C; pH was controlled between 5.2 and 5.3, and the hydraulic retention time (HRT) was 12 h. Online measurements were taken for ORP, pH, temperature, %CO2, gas output and %H2, and data logged using a MatLAB® data acquisition toolbox. Steady-state operation was obtained at 10, 20 and 40 g/L of sucrose in the influent, but a subsequent step change to 50 g/L was unsustainable. The hydrogen content ranged between 50% and 60%. The yield of hydrogen decreased as the substrate concentration increased from 1.7 ± 0.2 mol/mol hexose added at 10 g/L, to 0.8 ± 0.1 mol/mol at 50 g/L. Sparging with nitrogen improved the hydrogen yield by at least 35% at 40 g/L and at least 33% at 50 g/L sucrose. Sparging also enabled steady-state operation at 50 g/L sucrose. Addition of an extra 4 g/L of n-butyric acid to the reactor operating at 40 g/L sucrose increased the butyrate concentration from 9,830 to 18,900 mg/L, immediately stopping gas production and initiating the production of propionate, whilst the addition of 2 g/L taking the butyrate concentration to 12,200 mg/L did not do so. It was shown that operation at 50 g/L sucrose in a CSTR in butyrate fermentation is possible.

    Iaith wreiddiolSaesneg
    Tudalennau (o-i)971-979
    Nifer y tudalennau9
    CyfnodolynBiotechnology and Bioengineering
    Rhif cyhoeddi5
    Dynodwyr Gwrthrych Digidol (DOIs)
    StatwsCyhoeddwyd - 5 Ebr 2006

    Ôl bys

    Gweld gwybodaeth am bynciau ymchwil 'Influence of substrate concentration on the stability and yield of continuous biohydrogen production'. Gyda’i gilydd, maen nhw’n ffurfio ôl bys unigryw.

    Dyfynnu hyn