Filtrate Treatment Facility at Blue Plains – Concept to Final Design

District of Columbia Water and Sewer Authority is currently constructing new solids processing facilities at Blue Plains, based on thermal hydrolysis, anaerobic digestion, and belt filter presses. The filtrate, which will have high concentrations of ammonia and carbon in the form of volatile fatty acids, will be treated in a sidestream facility before being returned to the plant. Sidestream treatment is needed to minimize recycle of ammonia to the mainstream process where it would exert significant oxygen and chemical demands. The DEMON® deammonification process was selected as the most cost-effective treatment mode. The DEMON® process will be applied in six sequencing batch reactors operating in parallel. The DC Water DEMON® will be the largest facility of its type in the world. Scale-up and numerous detailed design features were incorporated during detailed design. Lessons learned in taking Concept Design through preparation of detailed Final Design will be presented.