Lagoon Digestion – Old Dog, New Tricks

Solids or sludge lagoon digestion has been practiced around the world historically as a low-cost method to stabilize solids. Primary disadvantages have been the odor levels often created by open lagooning and the land area required. A newer concern is the methane emissions to the atmosphere from open lagooning, and the impact of methane release on climate change.Covering such digestion lagoons, collecting the biogas, and using the biogas in proper combustion equipment, alleviates major problems of open lagoon digestion. Cover materials and installation methods and practices have improved over the years, so that these cover systems are now more reliable, with less change of puncture or damage which results in release of biogas and odor to the atmosphere. Covered municipal wastewater sludge lagoon digesters are rare, but should be a process receiving more attention due to the success of covered lagoon digesters animal and industrial wastes.