Sewage gas for electricity generation within a gas engine to produce power can offset site operational costs through electricity exported to the grid.
Wastewater treatment facilities use sewage gas as a fuel source when used in generator sets (gas engines). Through the process of anaerobic digestion, the biogas produced by the wastewater digesters used in the water treatment process is captured and used by the MWM gas engines to power the waste treatment plant. The electricity produced is then exported to the electricity grid, offsetting the sites operational costs.
Recent environmental requirements and process innovations have led to advanced anaerobic digestion where the sewage sludge is pre-treated thermally and/or enzymically before the digestion process. This pasteurises the sludge and increases conversion to biogas. Often the process requires steam for heating and this is produced from the exhaust heat of the biogas CHP engine.
Benefits of CHP for Sewage Gas
Using sewage gas for electricity generation can provide many benefits, including:
- Renewable energy generated from a waste material through Combined Heat and Power (CHP)
- Reduces operational costs
- Export power used as an income generation tool
- Reduces CO2 emissions
- Cost-effective and proven technology
Sewage Gas CHP
Mogden Sewage Treatment Works utilises a 6MWe Combined Heat and Power (CHP) plant which replaced the sites existing dual fuel system. The CHP installation significantly improves serviceability, availability, power generation and reduces carbon emissions.
Elsewhere, the facility is capable of treating 50 percent more sewage waste to cater for London’s growing population and meets the tighter effluent quality standards set by the Environmental Agency.
Gas to Power
Edina remains the preferred biogas CHP supplier, installer and maintenance provider on most advanced digestion and anaerobic digestion projects commissioned in the UK, with over 70MWe installed across the sewage and wastewater treatment sectors.