4. Conclusion
Biogas production is best tool to solve the problems of global
warming, energy security and waste management. Anaerobic codigestion
of the concentrated pig manure with grass silage was
used, and this research carried out in full-scale three CSTRs was
operated at mesophilic temperature. The results obtained in this
study suggest that co-digestion of pig manure and grass silage is
a promising approach for improving biogas production. The upgraded
gas was containing CH4 (89.35%), CO2 (10.05%), O2 (0.02%)
and H2S (