| Popis: |
While the individual need for dosage of nickel and cobalt in anaerobic digesters has been established, together with the biochemistry underpinning such need; their co-requisite in anaerobic digestion of acetate has not been extensively studied. In addition, the balance between the catalytic and toxic concentrations of nickel and cobalt in anaerobic acetate digesters is not well documented. The aim of this study was to examine and evaluate the effects of individual and combined dosage of nickel and cobalt on biogas production as well as on methanogenic population balance of a mesophilic (37°C) anaerobic acetate digester so as to determine their catalytic and toxic concentrations. Four semi-CSTR digesters were daily fed acetate at a loading rate of 1.8 g L-1 d-1 and were operated at a HRT of 10 days for this investigation. Co-dosage of nickel and cobalt in anaerobic acetate digesters were found to lead to increased biogas production in an additive manner, with the sole dosage of nickel resulting in more biogas production than that of cobalt. At a large enough concentration, these elements were found to inhibit biogas production. |
