Abstract:
Energy is one of the most important factors for human development and global economic
growth. Renewable energy techniques give a great opportunity for the reduction of greenhouse
gas emissions and decreasing global warming via replacing traditional energy sources. Biogas
is a clean, environmental friendly and renewable form of energy generated when micro organisms degrade organic materials in the absence of oxygen. This study was aimed to evaluate
the biogas production potential of Ageratum conyzoides and cow manure in combination or
separately under anaerobic conditions. There was five treatments (T1=100%AC,
T2=65%AC+35%CM, T3=50%AC+50%CM, T4=35% AC+65%CM and T5=100%CM) of
substrates. The experiment was done by completely randomized design using batch mode
operated digesters in the microbiology laboratory of Haramaya University for 30 days of
fermentation. In all the treatments, Physico-chemical parameters such as pH, total solids,
volatile solids, organic carbon, and carbon to nitrogen ratio were measured before and after
AD. The experimental results showed that with the increment in biogas yield, there is a reduction
in Total solids, Volatile solids, and organic carbon. Gas production was observed in all of the
digesters from day two onwards of anaerobic digestion and measured by using the water
displacement method. The highest amount of daily mean biogas was produced on the 12th day in
T2 (54.83ml). The cumulative biogas yield measured from T1, T2, T3, T4, and T5 were 482.67ml,
805.33ml, 652.47ml, 544.83ml, and 410.30ml, respectively. The research result showed that it is
possible to generate biogas from Ageratum conyzoides. Therefore, the researcher recommended
that Ageratum conyzoides can be used in a mix ratio of 65% AC with 35% CD in large-scale
production of biogas
