Severn Trent to supply world’s largest fixed-film denitrification system to Baltimore WWTP

The TETRA Denite fixed-film biological denitrification process will be used to reduce high levels of nutrients discharged into the Chesapeake Bay from the Back River WWTP.

The installation will be the world’s largest fixed-film denitrification system. The US$24 million project consists of 52 filters — four sets of 13 (3.6m X 30.5m). Each set will operate independently of the others with its own controls and operation programming. All 13 systems will share the same backwash and chemical feed system.

When the project is completed, Back River WWTP’s effluent quality will be less than 5mg/l Total Suspended Solids, less than 1.0 mg/l Nitrate-Nitrogen, less than 4.0 mg/l Total Nitrogen and less than 10 mg/l Chemical Biological Oxygen Demand.