Source
Journal of Engineering Research, v. 20, no. 1, p. 12-22.
English abstract
In this study, two sides were
studied. First one included single and combined
pretreatment which were performed to treat
milled rice husks compared to increase the
production of biogas untreated rice husks. The
other side included investigate the effect of two
types of mixing: mixing rice husks and okra stalks
using three mixing ratios inoculated with ostrich
dung compared to rice husks and okra stalks
inoculated with ostrich dung separately and
mixing ostrich dung and cow manure using three
mixing ratios with rice husks compared to using
rice husks inoculated with ostrich dung and cow
manure separately. The ten reactors, which were
carried out in this study, were in batch mode.
Single pretreatment included hydrothermal and
oxidative pretreatment with 50% (v/v) H2O2,
while combined pretreatment consisted of both
hydrothermal and H2O2 pretreatment. The cow
manure was used as inoculum in this anaerobic
co-digestion process. The results clarified that the
increase of biogas productions were by 5.42%,
48.05%, and 59.07% for hydrothermal, H2O2, and
combined pretreatment of hydrothermal and
H2O2, respectively. For first mixing, 25:75 ratio
(rice husks: okra stalks) was better than other
ratios in the production of biogas (48.77 ml/g VS).
In the second case of mixing, 75:25 ratio (ostrich
dung: cow manure) was better than other ratios in
the production of biogas (21.85 ml/g VS). Kinetic
study was applied using modified Gompertz
model, and there was well agreement between the
predicted and measured values of the all
pretreatments with correlation coefficient > 0.95.
The pretreatment samples of rice husks and the
mixing of materials improve the production of
biogas and methane.
