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Digester Projects at Water Resource Recovery Facilities (WRRFs)

The projects listed below are currently operating co-digestion systems at Water Resource Recovery Facilities (WRRFs).  The profiles represent real-world examples of projects that demonstrate the benefits of combining organic feedstocks from offsite sources to boost biogas production.

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  • Des Moines Metro digester project (PDF)(1 pg, 319 K, May 16, 2016)
    The Des Moines Wastewater Reclamation Facility (WRF) is located in De Moines, IA. The WRF uses biogas to fuel boilers and power internal combustion engines. The engine waste heat is recovered to heat the digesters and several facility buildings. The remaining digester gas is sold to a nearby vegetable oil refinery. The WRF processes a variety of feedstocks including Fats, Oils and Grease (FOG) and food processing wastes which has doubled their biogas production.