How organic waste becomes biogas
Anaerobic digestion uses microorganisms to break down biodegradable material without oxygen. The raw gas normally contains methane, carbon dioxide, moisture, hydrogen sulphide, and trace compounds. A CBG project adds cleaning, upgrading, and compression so the methane-rich product can meet its intended fuel specification.
- Feedstock reception and contamination removal
- Size reduction, dilution, or other preprocessing
- Controlled digestion and gas capture
- Gas cleaning, methane upgrading, and compression
- Digestate separation and organic-output processing
Why feedstock yield is never one fixed number
One wet ton of press mud, cattle dung, food waste, or energy crop does not contain the same quantity of biodegradable solids. Moisture, total solids, volatile solids, ash, storage loss, season, contamination, and inhibitors all affect the recoverable methane.
- Use representative samples rather than one visual inspection
- Measure TS, VS, pH, nutrients, contaminants, and BMP where relevant
- For liquid effluent, use flow and COD-based analysis
- Model collection, storage, rejection, ramp-up, downtime, and methane recovery
From theoretical output to saleable CBG
A laboratory result is a potential, not a guaranteed operating output. The final saleable gas depends on field realization, digester stability, capture efficiency, upgrading recovery, methane slip, off-spec gas, flaring, and plant availability. The free calculator therefore shows a range rather than one exact production value.
- Compare low and high yield scenarios
- Use monthly feedstock availability, not only an annual average
- Separate raw biogas from saleable CBG
- Confirm product quality and delivery requirements before investment
Use the estimate in project planning
The output range supports early conversations about project class, waste diversion, fuel value, and disposal savings. The next step is a site and feedstock assessment that converts assumptions into a process basis, mass balance, preliminary equipment scope, utility demand, project schedule, and financial model.
- Run the waste and CBG calculator
- Record every assumption and source
- Test the feedstock and confirm seasonal supply
- Prepare a project-specific feasibility study