Use of compost extract as acclimatization accelerator for methane oxidation biosystems.

Area of Science:

• Environmental microbiology
• Bioremediation technologies
• Methane oxidation

Background:

• Methane oxidation biosystems require lengthy acclimatization periods for microbial community establishment.
• Accelerating this process is crucial for efficient methane mitigation.

Purpose of the Study:

• To evaluate if compost extract inoculation accelerates acclimatization and enhances methane oxidation capacity in biosystems.
• To determine optimal compost extract dilutions and application methods.

Main Methods:

• Batch and continuous-flow column assays were conducted using biosolids and leaf compost.
• Compost extract was added at various dilutions (100%, 66.6%, 33.3%) with different initial methane (CH4) concentrations.
• Engineered media (biosolids compost-gravel mixture) was used in column experiments.

Main Results:

• Compost extract reduced acclimatization time by 50-82% and increased methane oxidation rates (11-70 µg CH4·gdw⁻¹·h⁻¹).
• Continuous-flow columns showed full methane removal within 3 days with inoculation, versus 18+ days without.
• Microbiological analysis confirmed a preserved diverse methanotrophic community.

Conclusions:

• Compost extract inoculation is a simple, low-cost, and effective method to accelerate biosystem start-up.
• This approach enhances early-stage methane removal and mitigation capacity.
• Implementation can significantly shorten the stabilization period for methane oxidation biosystems.