Six years strong: Landia’s biogas digester mixing system delivers uninterrupted performance

At a leading Energy & Recycling Facility operated by a water utility in northern England, Landia’s biogas digester mixing system has marked six years of flawless, uninterrupted operation.

Since its commissioning, the facility has consistently achieved its daily target of over 22,000 normal cubic meters (Nm³/d) of biogas. This performance is driven by Landia’s externally mounted GasMix system, which thoroughly mixes thickened sewage sludge in two 7,306m³ anaerobic digesters. Over five years of continuous 24/7 operation, only one pump has required servicing—a testament to the system’s robust design and reliability.

Paul Davies, Landia’s Key Account Manager, noted: “Our GasMix system, featuring Landia’s Chopper Pump, has proven to be exceptionally dependable. It’s a straightforward yet highly effective solution. By ensuring comprehensive mixing, it helps maximize gas quality. Maintenance is also simplified, as all mechanical components are located outside the digester, allowing for easy access.”

Commissioned in 2019, the facility was established as a strategic regional sludge treatment hub, handling both indigenous and imported sludge in liquid and cake forms. It plays a critical role in the utility’s strategy to reach net zero carbon emissions by 2030.

The Landia GasMix system continuously suspends solids and reduces particle size, preventing the formation of surface crusts that commonly hinder digester performance. At the heart of the system, the Landia Chopper Pump recirculates thick sludge from the tank bottom, chopping solids to accelerate digestion. This action helps prevent grit accumulation and blockage of pipes and nozzles—keeping the system running smoothly and efficiently.