Mesophilic and thermophilic biohydrogen production using cassava starch wastewater in a CSTR

摘要

The objective of this work is to compare and evaluate the production of biohydrogen (bio-H_2) from cassava starch wastewater at mesophilic and thermophilic conditions and to elucidate the metabolic routes involved. This system consisted of a continuous stirred-tank reactor for hydrogen production under the influent organic loading rate (OLRs) of 2.08, 5.05, 12.04, 23.34, and 30.87 kg COD/(m~3·d) for mesophilic temperature and 2.29, 4.47, 12.52, 22.09 and 28.86 kg COD/(m~3·d) for thermophilic temperature with Hydraulic Retention Time of 24, 16, 12 and 8 hours and pH maintained 5 to 6. The steady state of hydrogen production was 3131 ml/L·d obtained at the OLR of 23.34 kg COD/(m~3·d) with the COD removal of 85, and the hydrogen production of 2007 ml/L.d with a COD removal of was obtained at the OLR of 28.86 kg COD/(m~3·d). The maximum of 85 of the cassava starch wastewater was converted to hydrogen at the OLR of 23.34 kg COD/(m~3·d) at mesophilic conditions with HRT of 8 h and hence the mesophilic condition favoured the hydrogen production using cassava starch wastewater.