A wastewater treatment plant (WWTP) in Wisconsin has increased the biogas yield at its AD plant by 25%, thanks to the installation of a new digester mixing system.
Instead of capacity decreasing because of rags, grit and debris steadily accumulating at the bottom of two digesters (334,000 gallons (1,264m3) and 183,000 gallons (693m3) respectively), the tanks’ contents at the city of Sparta (situated between Milwaukee and Minneapolis) are now comprehensively mixed by Landia’s GasMix system.
A simple, yet highly effective design, comprising the proven Landia Chopper Pump (invented by Landia in 1950), and strategically-angled venturi nozzles, all mechanical equipment can be accessed on the outside of the digesters for easy maintenance.
Sparta’s wastewater treatment plant manager, Ed Hanson, commented: “Our old, basic mixing system just blew air upwards in the digesters, which wasn’t very efficient.
“Also, we couldn’t get to it to carry out maintenance or make repairs without draining the tanks down. This can take you offline for a long time, which nobody wants when trying to produce biogas.
“Eventually, the old mixing system was...
Sparta’s biogas yields soar with new digester mixing system
