| Summary: | Adequacy of petroleum as a source of energy has almost arrived at the end
of his time. Biogas is a renewable energy source that can be used to meet most of
the world's energy needs. Fruit waste has good potential as a substrate because of
the high content of organic matter, but some fruits contain inhibitors compounds.
Citrus fruits, besides acidic, also contain limonene. In the process of anaerobic,
methane-producing microorganisms (methanogens) are the most sensitive to the
presence of these inhibitors. Start-up is key to the success of biodigesters in order
to operate optimally. Balanced growth of methanogenic and non methanogenic
microbial is developed on the start-up process so that the whole series of reactions
that occur are hydrolysis, acidogenesis and methanogenesis can perform well.
Start-up process can also be used as a process of adaptation of microorganisms to
the inhibitor, during a given enough time.
This study aims to try the start-up strategy to run semi-continuous biodigesters use
fruit waste in a proportion with cow dung as substrate. Biodigester designed using
a loading rate of 40 kg/(m3.day) with an effective volume of 16 liters of slurry.
Feed was given at 6% TS%. Biodigester equipped with inlet feed, effluent channel
expenditure, manometers, magnetic stirrer and a 12 liters gas holder. The feed
composition comprises a mixture of fruit of melon, citrus and apples, mixed with
a certain ratio with cow dung.
The results showed that with gradual increase of fruit waste ratio on the feed
composition, the biodigester can produce biogas 9.158 mL/g.d. Biodigester can
handle fruit waste composition up to 35% or equivalent to 44.44 ppm limonene
concentration on daily feed. Biodigesters can still operate optimally even with the
lowest pH to 6.6. Highest methane content is 75.63% at the feed composition S1.
The average methane concentration obtained was 62.15%. Acclimatization time
required biodigesters for feed composition S0, S1, S2, S3, S4 and S5 respectively
21, 14, 18, 24, 28 and 65 days.
|
|---|